Skip to main content

MRI-detected extramural venous invasion of rectal cancer: Multimodality performance and implications at baseline imaging and after neoadjuvant therapy


MRI is routinely used for rectal cancer staging to evaluate tumor extent and to inform decision-making regarding surgical planning and the need for neoadjuvant and adjuvant therapy. Extramural venous invasion (EMVI), which is intravenous tumor extension beyond the rectal wall on histopathology, is a predictor for worse prognosis. T2-weighted images (T2WI) demonstrate EMVI as a nodular-, bead-, or worm-shaped structure of intermediate T2 signal with irregular margins that arises from the primary tumor. Correlative diffusion-weighted images demonstrate intermediate to high signal corresponding to EMVI, and contrast enhanced T1-weighted images demonstrate tumor signal intensity in or around vessels. Diffusion-weighted and post contrast images may increase diagnostic performance but decrease inter-observer agreement. CT may also demonstrate obvious EMVI and is potentially useful in patients with a contraindication for MRI. This article aims to review the spectrum of imaging findings of EMVI of rectal cancer on MRI and CT, to summarize the diagnostic accuracy and inter-observer agreement of imaging modalities for its presence, to review other rectal neoplasms that may cause EMVI, and to discuss the clinical significance and role of MRI-detected EMVI in staging and restaging clinical scenarios.

Key points

  • T2WI demonstrates EMVI as an expanded, irregular vessel with intermediate tumor-signal intensity.

  • CT can sometimes depict EMVI as a heterogeneously enhancing, serpentine cord-like structure

  • Inter-observer agreement in assessing the presence or absence of EMVI is variable.

  • EMVI is a predictor of poor prognosis and indicates biologic aggressiveness.

  • EMVI may be seen in association with rectal  tumors other than adenocarcinoma.


Colorectal cancer is the third most common neoplasm in adults, with approximately 43,000 patients diagnosed with rectal cancer in the United States in 2020 [1]. MRI provides detailed imaging of rectal cancers and relevant pelvic structures and is routinely used to evaluate tumor extension beyond the muscularis propria of the rectal wall as well as involvement of the mesorectal fascia [2,3,4]. Rectal cancer MRI is routinely used to inform therapeutic decisions, e.g., the use and type of neoadjuvant therapy, oncologic surgical planning, and preoperative assessment after neoadjuvant therapy [5].

Direct tumor invasion into the extramural veins on histopathology, known as extramural venous invasion (EMVI), has been recognized as an indicator of poor prognosis [6, 7]. Brown et al. found that MRI-detected EMVI correlated well with histopathological EMVI [8]. MRI-detected EMVI is now widely accepted as an independent poor prognostic factor for disease-free survival. Consequently, MRI-detected EMVI is an important consideration in therapeutic decision-making similar to histopathological EMVI [9]. Despite the fact that diagnosis can be challenging, radiologists should evaluate rectal cancers for EMVI at pelvic MR as it is an important imaging biomarker for nodal or distant metastasis, unfavorable prognosis, and need for neoadjuvant therapy [10].

This article reviews the imaging findings of EMVI on MRI and CT, summarizes the diagnostic accuracy and inter-observer agreement for detection of EMVI, and reviews the clinical significance and role of MRI-detected EMVI in staging and restaging scenarios with an aim to disseminate a common understanding of EMVI and its varied appearances.

Venous anatomy of the rectum

Understanding the rectal venous plexus anatomy can be helpful when aiming to accurately identify EMVI on MRI. The venous drainage of the anorectum occurs via two interconnected plexuses, the inner submucosal plexus of the anorectum (the internal rectal plexus) and the outer muscularis plexus (the external rectal plexus). Venous drainage of the upper 2/3 of the rectum is via the superior rectal/hemorrhoidal veins, which drain into the inferior mesenteric vein [11]. Venous drainage of the lower 1/3 of the rectum is via the middle and inferior rectal veins, which drain into the internal iliac veins, common iliac veins, and inferior vena cava (Fig. 1). The middle rectal vein is found in 32.6% of individuals, and is unilateral in the majority [12]. Thus, venous return from the rectum enters both the portal and systemic circulation.

Fig. 1

Venous anatomy of the rectum. The upper 2/3 of the rectum drains via the superior rectal vein (A SRV) into the inferior mesenteric vein (B IMV). The lower 1/3 of the rectum drains via the middle (a MRV) and inferior rectal vein (a’ IRV) into the internal iliac vein (b IIV), common iliac vein (c CIV), and inferior vena cava (d IVC)

EMVI in histopathology

EMVI is defined histopathologically as the presence of tumor cells within blood vessels located beyond the muscularis propria of the rectal wall (Fig. 2a); however, desmoplastic reaction and endothelial destruction induced by tumor invasion destroy the vessel wall and can preclude identification of venous anatomy, making EMVI challenging to detect even at histopathology [13]. An elastin stain highlights elastic fibers present in the adventitia of veins (but not lymphatics), and improves the identification of EMVI compared to routine hematoxylin–eosin stain alone (Fig. 2b) [14, 15]. The detection of venous invasion is dependent on the number of examined tissue blocks or slides [16]; therefore, imaging detection of EMVI can guide the pathologist in selecting the location and number of tissue samples for slides.

Fig. 2

Extramural venous invasion on histopathology. a The tumor cells (asterisk) are surrounded by a vessel on hematoxylin–eosin stain. b Elastin stain is helpful to depict extramural venous invasion (asterisk) by highlighting elastin fiber (arrowheads) around tumor cells. The scale bar is 500 µm

Invasion of tumor into blood vessels is considered to be an initial step in hematogenous metastasis [17], and histologic venous invasion of colorectal carcinoma was identified as a risk factor for metastatic disease in the 1930s [6]. Venous invasion is categorized as intramural or extramural based on whether the location is within or beyond the bowel wall. Histopathologically-detected EMVI portends a worse 5-year survival rate and an increased risk of hepatic metastasis compared to intramural venous invasion, which demonstrates a worse prognosis than no venous invasion [7, 16]. The presence of EMVI on resection specimens following neoadjuvant therapy is associated with a significantly worse prognosis in patients with rectal cancer [18, 19]. If a patient did not receive neoadjuvant therapy prior to surgery, and the surgical histopathology shows high risk features, including EMVI, chemotherapy is often recommended following surgery.

EMVI in magnetic resonance imaging

The MERCURY study evaluated high-resolution rectal MRI with an in-plane resolution of 0.6 × 0.6 mm and reported that MRI could predict surgical margin status [20] and extramural depth equivalent to that on pathology with a difference less than 0.5 mm [3]. Using this same optimized scan protocol with high-resolution T2WI, Brown and colleagues also first described EMVI in the setting of rectal cancer and noted its presence to be an important prognostic finding, similar to EMVI on histopathology [8]. Rectal MRI is considered capable of depicting EMVI greater than 3 mm despite the spatial resolution of MRI being limited compared with histopathology [8].

EMVI at MRI is usually associated with primary tumor extending beyond the muscularis propria and into the mesorectal fat. The leading edge of the tumor with such extramural extension and associated EMVI is typically nodular or sawtooth  rather than smooth. The infiltrated vessel is contiguous with the primary tumor, may be expanded, and has lost the normal black signal flow void, which is replaced with intermediate signal T2 tumor intensity. The vessel often has irregular margins and may appear beaded or nodular on T2 and post contrast imaging (Fig. 3) [5, 21].

Fig. 3

Extramural venous invasion on T2-weighted image. A nodular-shaped structure (a arrow) arising from the ulcer crater and leading edge of the primary lesion (a asterisk) invades the mesorectal fascia (a arrowhead). The structure also  extends cranially in the mesorectal fascia (b arrow) and is branched (c arrows)

To help in assessing EMVI, Smith et al. developed a 5-point scoring system on T2WI based on the aforementioned MR imaging features [22]. This scoring system stratifies a broad spectrum of findings into five categories and has been used in several research studies [22,23,24,25,26,27,28,29,30,31,32]. Score 0 is defined as tumor extension through the muscle layer, without nodularity, and lacking vessels adjacent to the area of tumor penetration. Score 1 is defined as minimal extramural stranding and nodular extension, but not in the vicinity of any vascular structure. Score 2 is defined as stranding in the perirectal fat in the vicinity of normal diameter extramural vessels. Score 3 is defined by intermediate T2 signal intensity within a slightly expanded vessel with a smooth contour. Score 4 occurs when a perirectal vessel has an irregular contour or nodular expansion with internal intermediate T2 signal intensity [22]. A score of 0 or 1 is predictive of absence of EMVI at histopathology whereas scores of 3 or 4 are suggestive of the presence EMVI (Fig. 4). A score of 2 was initially defined as a negative [22], but subsequent research has shown that one-third of cases with this score can be positive histpathologically, so a score of 2 is often considered equivocal [26].

Fig. 4

Adapted from Smith NJ, et al. Br J Surg 2008 [22]

Extramural venous invasion scoring system based on T2-weighted images. a No vessel exists adjacent to the primary tumor (score 0). b Normal diameter vessel adjacent to the primary tumor demonstrates no tumor signal intensity (score 1). c Slightly expanded vessel without abnormal signal intensity (score 2). d Expanded vessel including obvious tumor signal intensity (score 3). e Expanded vessel with irregular or nodular contour containing tumor signal intensity (score 4).

Beyond the 5-point grading, additional features of MR detected EMVI have been investigated, including the significance of the number and diameter of involved vessels, the location (e.g., originating from the upper, middle, or lower rectum), and the causes of vascular involvement (i.e., EMVI arising from the primary tumor as opposed to involved lymph nodes or tumor deposits defined as satellite peritumoral nodules of carcinoma in the mesorectal fat remote from the primary tumor, with no sign of residual lymph nodes or identifiable vessels or neural structures [33]). EMVI arising from the upper rectum and larger vessels is associated with a greater risk of poor prognosis or distant metastasis [24, 34]. EMVI arising from lymph nodes or tumor deposits has been shown to carry a prognosis similar to EMVI arising from the primary rectal tumor [34].

Diffusion-weighted images (DWI) often depict the intravenous tumoral component as intermediate or high tumor-signal intensity within normal or slightly expanded extramural vessels adjacent to the primary tumor (Fig. 5). Despite the potential pitfalls of DWI such as susceptibility artifact, limited spatial resolution, T2 shine through, and fibrosis, DWI can be helpful in identifying EMVI at both initial staging and restaging after neoadjuvant therapy [35, 36].

Fig. 5

Extramural invasion on diffusion weighted imaging. A 41-year-old man with rectal adenocarcinoma. T2-weighted image demonstrates a distended perirectal vessel with a lack of flow void and central tumor signal intensity which is contiguous with the primary rectal tumor (a arrow). Diffusion-weighted image shows a high signal intensity cord-like structure contiguous with the primary rectal tumor (b arrow)

On contrast-enhanced T1 weighted images (CE-T1WI), EMVI can be identified as either enhancing tumor within the vessel or as a non- or hypoenhancing intraluminal filling defect [26] within an expanded vessel (≥ 3 mm), that is contiguous with the primary tumor (Table 1) [30]. The delayed phase of contrast enhancement can be helpful as intravenous mixing of contrast during early phases of enhancement in a normal vein may mimic EMVI [41]. CE-T1WI has not been shown to increase accuracy for rectal cancer staging/restaging, and its routine use remains controversial [37,38,39] as concluded by expert panels from Europe [40] and North America [41]. While 65% of North American panelists reported that they use gadolinium-based contrast media in MRI examinations for rectal cancer, only 29% of European panelists reported doing so [42]. However, CE-T1WI may be a helpful adjunct when the absence/presence of EMVI is equivocal by T2WI [26] (Fig. 6).

Table 1 Imaging findings of extramural venous invasion
Fig. 6

Extramural invasion on contrast-enhanced T1-weighted image. A 56-year-old male with rectal adenocarcinoma. The dilated vessel which is in continuity with the tumor has an irregular margin and contains intermediate signal intensity rather than flow void on the T2-weighted image (a arrow). The tumor in the vessel enhances on the contrast-enhanced T1-weighted image (b arrow)

Performance of rectal cancer MRI to detect EMVI

Brown et al. showed that rectal cancer MRI revealed 83% of histopatologically-detected EMVI with a diameter greater than 3 mm [8]. A recent meta-analysis by Kim et al. showed that MRI had a pooled sensitivity of 61% and specificity of 87% for detecting EMVI in colorectal cancer using histopathology as the reference standard [43]. Table 2 shows sensitivity, specificity, and inter-observer agreement of MR for detection of EMVI in rectal cancer using T2WI alone or T2 combined with DWI or CE-T1WI before and after neoadjuvant therapy [8, 22,23,24,25,26,27,28,29,30,31,32, 44]. Inter-observer agreement for assessing EMVI employing the 5-point scoring system is variable (κ = 0.372–0.828), even when T2WI is used alone [26,27,28,29,30,31,32].

Table 2 Estimated Performance of MRI for extramural venous invasion

Data regarding the value of DWI in detecting EMVI are conflicting. Ahn et al. reported that the addition of DWI reduced inter-observer agreement with no additional diagnostic benefit [32]. Conversely, Fornell-Perez et al. reported that the addition of DWI improved diagnostic accuracy in detecting EMVI, especially in post chemoradiation therapy patients [45]. Interestingly, Coruh et al. found that the ADC (apparent diffusion coefficient) values of the primary tumor are significantly lower in EMVI positive tumors [46].

Jhaveri et al. showed that the sensitivity and specificity of rectal MRI for EMVI did not significantly change with the addition of contrast-enhancement (for initial or restaging studies), but that interobserver agreement remained good [26]. Similarly the meta-analysis by Kim et al. showed no significant improvement in performance with gadolinium contrast or DWI [43]. In contrast, Lui et al. showed that contrast enhancement may improve sensitivity but at the cost of reduced interobserver agreement [30].

EMVI in computed tomography

Compared with MRI, the role of CT in assessing EMVI is limited because of its lower contrast resolution. However, CT can be an alternative to assess EMVI in patients who have a contraindication to MRI or who are unable to undergo MRI due to claustrophobia. On CT, EMVI is often seen as a heterogeneously enhancing, serpentine cord-like structure connecting veins with the irregular, contiguous margins of the primary tumor (Fig. 7). Ortega et al. investigated the diagnostic accuracy of CT-detected EMVI in rectal cancer using venous distension and intravascular tumor enhancement as the imaging criteria and using MRI-detected EMVI as the reference standard. They reported a high specificity of 100%, but low sensitivity of 14% and NPV of 47% [47]. Routine mention of CT-detected EMVI in clinical reports is not required; however, the presence of CT-detected EMVI can aid in therapeutic decision making in patients who have a contraindication to MRI, so reporting EMVI may be helpful when detected. Further investigation is warranted to determine the clinical significance of CT-detected EMVI.

Fig. 7

Extramural venous invasion on CT. A 47-year-old female with rectal adenocarcinoma. A nodule with an irregular margin containing intermediate signal intensity is observed in the mesorectum on axial T2WI (a arrow). Sagittal T2WI reveals a cord-like structure with tumor signal intensity in the superior rectal vein (b arrow) which drains to the inferior mesenteric veins (b arrowheads) Similarly, contrast-enhanced CT demonstrates an enhancing irregular nodule within the posterior mesorectum on the axial image (c arrow). On the sagittal image a cord-like nodular mass is contiguous with the dilated superior rectal vein (d arrow) and inferior mesenteric veins (d arrow heads) on the sagittal image. The diameters of the inferior mesenteric and superior rectal veins are 8.5 mm (e arrow) and 4.8 mm (f arrow), respectively, which is suggestive of the presence of EMVI

Dilation of the superior rectal and inferior mesenteric veins may help to predict EMVI (Fig. 7). Wu et al. reported that using a cut off value of 3.7 mm for the diameter of the superior hemorrhoidal vein, lymphovascular invasion by rectal cancer could be predicted on CT [48]. Similarly, in a study by Coruh et al., the diameter of the superior rectal and the inferior mesenteric veins were significantly larger in patients with EMVI on CT. Cutoff values of 3.95 mm for the superior rectal vein and 5.95 mm for the inferior mesenteric vein predicted EMVI with 93.3% and 93.3% sensitivity and 67.9% and 71.4% specificity, respectively [46]. It was hypothesized that the presence of an intravenous tumor may result in increased blood flow in the major drainage pathways of the rectum such as the superior rectal and inferior mesenteric veins, and that dilation may be an indirect indicator of EMVI. Likewise, increased venous drainage caused by tumor neoangiogenesis may result in vein dilation.

Clinical significance of MRI-detected EMVI

Multiple studies have demonstrated the clinical significance of EMVI detected on MRI as a predictor of poor prognosis or biologic aggressiveness in rectal cancer. MRI-detected EMVI is generally present in patients with T3 and nodal disease and is consequently, at least in North America, used to determine which patients will benefit from neoadjuvant therapy. Conversely, the overuse of neoadjuvant therapy in rectal cancer patients does not improve survival and can result in bowel and sexual dysfunction [49], and a recent European clinical trial has advocated that rectal cancer MRI demonstrating absence of EMVI may facilitate patient selection for primary surgery [50].

Predicting survival

MRI-detected EMVI is reported to be an independent significant prognostic factor for overall disease-free survival and systemic recurrence in rectal cancer [51]. In locally advanced rectal cancer, MRI-detected EMVI predicted decreased disease-free survival (hazard ratio: 2.46) [52]. In another study, MRI-detected EMVI before neoadjuvant therapy was an independent poor prognostic factor for progression-free survival (hazard ratio: 1.85) [53], disease-free survival (hazard ratio: 1.35–31.33) [29, 54,55,56,57,58] and overall survival (hazard ratio: 1.18–2.90) (Fig. 8) [29, 59]. MRI-detected EMVI after neoadjuvant chemotherapy has also been shown to be a predictor of decreased disease-free survival (hazard ratio: 1.97–2.68) [25, 29], recurrence-free survival (hazard ratio: 2.74) [60] and overall survival (hazard ratio: 1.98–4.23) [29, 59, 60] (Table 3).

Fig. 8

Local recurrence after surgery from residual disease associated with positive circumferential margin due to extramural venous invasion. A 58-year-old man with rectal cancer. T2-weighted (a) and postcontrast (b) coronal image before treatment demonstrate nodular-shaped structure (black arrows) on the right extending to the mesorectal fat tissue, and worm-shaped (white arrows) structure on the left with tumor signal intensity arising from the primary lesion, indicating extramural venous invasion (EMVI) extending the mesorectal fascia (arrow heads). Axial T2-weighted image shows a primary tumor (c asterisk) and an irregular tumoral deposit in and abutting the mesorectal facia near the left pelvic sidewall (c arrow). Axial and coronal 18F-FDG-PET/MRI images 23 months after surgery following neoadjuvant therapy show FDG avidity corresponding to a developed nodular recurrence at the same location (df arrows)

Table 3 Relationship between MRI-detected extramural venous invasion  and patient outcome

Rectal cancer MRI can also demonstrate in situ evidence of response or progression of EMVI after neoadjuvant therapy. Also, a change in MRI-detected EMVI status from positive to negative has been shown to predict histopathologic response [61]. Additionally, patients who have significant response of MRI-detected EMVI after neoadjuvant therapy, defined as more than 50% of the intravascular tumor content converted to low signal intensity fibrosis (i.e., signal intensity as low as the muscularis propria), have improved disease-free survival [62]. Regarding surgery, EMVI at initial staging MRI was a risk factor of failure to convert from positive to negative circumferential resection margin by neoadjuvant chemoradiotherapy [63]. Even when considering patients with positive resection margins, patients with EMVI have decreased survival compared to those without EMVI [64].

Predicting lymph node and distant metastases

In one study, EMVI score correlated with histologic lymph node stage [28]. In other studies, MRI-detected EMVI was found to be present in about a quarter of patients with rectal cancer, and had a specificity of about 81% for predicting N2 [23] and 88% for regional lymph node metastases [23, 27]. MRI detected-EMVI is also associated with a significantly higher risk for both synchronous [24, 65] and metachronous metastasis [66]. Approximately 25% of rectal cancer patients with EMVI on MRI developed subsequent liver and lung metastases at 1-year, compared to about 7% of patients without EMVI (Relative risk: 3.70) [66]. These findings are in keeping with the concept that EMVI may be the first step in hematogenous metastasis [17]. Table 4 summarizes the results of the studies correlating MRI-detected EMVI with lymph node and distant metastases.

Table 4 Risk of lymph node and distant metastasis with MRI-detected extramural venous invasion

Extramural venous invasion of other rectal tumors

Rectal neoplasms other than usual adenocarcinomas such as squamous cell carcinoma, mucinous adenocarcinoma, and neuroendocrine tumor also can invade perirectal vessels (Figs. 9, 10, 11).

Fig. 9

Extramural venous invasion in mucinous adenocarcinoma. A 53-year-old man with rectal mucinous adenocarcinoma. The circumferential rectal tumor shows high signal intensity on coronal T2WI (a asterisk). Peripheral heterogeneous enhancement is observed on contrast enhanced T1WI (b asterisk). The intravenous component demonstrates signal intensity and enhancement similar to the primary lesion (a, b arrows)

Fig. 10

Extramural invasion in squamous cell carcinoma. A 58-year-old male with rectal squamous cell carcinoma. A nodular, elongated structure extends cranially from the right side of the circumferential rectal tumor (a, b arrow)

Fig. 11

Extramural venous invasion in neuroendocrine tumor. A 50-year-old man with poorly differentiated neuroendocrine tumor, large-cell type. On the T2WI a tubular structure with irregular margins and signal intensity similar to the tumor (a arrow) extends from the rectal mass (a asterisk). The primary lesion (b asterisk) and extramural venous invasion (b arrow) are more conspicuous on DWI. Mesorectal lymph nodes which were histopathologically proven to be nodal metastases are depicted on T2WI and DWI (a, b arrowheads)

Mucinous rectal carcinoma is a distinct pathologic subtype of rectal cancer defined as a tumor composed of greater than 50% extracellular mucin and neoplastic epithelium surrounded by extracellular mucin lakes on histopathology [13]. The primary tumor is markedly hyperintense on T2WI owing to extracellular mucin [67]. Following administration of IV contrast material, the mucinous tumor has peripheral and heterogeneous enhancement. Mucinous rectal adenocarcinomas commonly have lower signal on higher b value DWI and a higher mean apparent diffusion coefficient compared to non-mucinous rectal cancers [68]. When EMVI is present, the intravenous tumor component shows the same signal characteristics as the primary tumor (Fig. 9). MRI is considered superior to biopsy in identifying mucinous malignancy secondary to sampling errors with biopsy [69]. Metachronous metastases are seen more often in mucinous carcinoma than non-mucinous carcinoma regardless of whether EMVI is present or absent [70].

Rectal squamous cell carcinoma is a rare tumor, which accounts for less than 1% of colorectal malignancies [71]. Risk factors include chronic infection, smoking, human immunodeficiency virus, and human papillomavirus [72]. Owing to its low prevalence, the imaging characteristics of squamous cell carcinoma are not well-documented, and the frequency and clinical significance of squamous cell carcinoma-associated EMVI are unknown (Fig. 10).

The rectum is a common site of neuroendocrine neoplasms. Rectal neuroendocrine tumor usually appears as a submucosal nodule or focal area of plaque-like wall-thickening; however, less commonly it can present as a large ulcerating, avidly enhancing, invasive mass [73]. The incidence of rectal neuroendocrine tumor has been increasing due to incidental detection, especially for small neoplasms. Large rectal neuroendocrine tumors can be difficult to differentiate from adenocarcinoma. EMVI of rectal neuroendocrine tumors in cross-sectional imaging has also not been well-described (Fig. 11). Neuroendocrine neoplasms smaller than 1.0 cm can be treated with resection; however, lymphatic and venous invasion are predictors of metastasis [74], and salvage surgery is recommended in patients with lymphovascular invasion [75].


MRI-detected EMVI correlates closely with histopathological EMVI and is a predictor of lymph node and distant metastases, tumor recurrence, and poor prognosis. Therefore, it is important to evaluate for the presence of EMVI on rectal cancer MRI examinations before and after neoadjuvant therapy to determine risk-stratification and therapeutic options. Despite the clinical significance of MRI-detected EMVI, inter-observer variability in assessing its presence or absence is problematic both at initial staging and after neoadjuvant treatment. Radiologists should therefore be familiar with the imaging features of EMVI and its implications for patient management. Findings of EMVI include expanded vessel caliber adjacent to the primary tumor, intermediate tumor signal intensity in the vessel, and irregular vessel margin. DWI and contrast enhanced T1 weighted images may be helpful adjuncts to T2WI and may help improve reader confidence in select cases. Further investigation is necessary to determine if multi-parametric MRI improves diagnostic performance without compromising interobserver agreement. In addition, further investigation is needed to assess the clinical importance of CT-detected EMVI and to determine whether detailed features of EMVI, including location, vessel diameter, and the number of involved vessels can improve risk-stratification.



Contrast enhanced T1-weighted image


Computed tomography


Diffusion-weighted image


Extramural venous invasion


Magnetic resonance imaging and rectal cancer European equivalence


Magnetic resonance imaging


T2-weighted image


  1. 1.

    Siegel RL, Miller KD, Jemal A (2020) Cancer statistics, 2020. CA Cancer J Clin 70:7–30

    Article  Google Scholar 

  2. 2.

    Inoue A, Ohta S, Nitta N et al (2018) Ex vivo MR imaging of colorectal carcinoma before and after formalin fixation: correlation with histopathologic findings. Abdom Radiol (NY) 43:1524–1530

    Article  Google Scholar 

  3. 3.

    MERCURY Study Group (2007) Extramural depth of tumor invasion at thin-section MR in patients with rectal cancer: results of the MERCURY study. Radiology 243:132–139

    Article  Google Scholar 

  4. 4.

    Gollub MJ, Arya S, Beets-Tan RG et al (2018) Use of magnetic resonance imaging in rectal cancer patients: Society of Abdominal Radiology (SAR) rectal cancer disease-focused panel (DFP) recommendations 2017. Abdom Radiol (NY) 43:2893–2902

    Article  Google Scholar 

  5. 5.

    Horvat N, Carlos Tavares Rocha C, Clemente Oliveira B, Petkovska I, Gollub MJ (2019) MRI of rectal cancer: tumor staging, imaging techniques, and management. Radiographics 39:367–387

    PubMed  Article  PubMed Central  Google Scholar 

  6. 6.

    Talbot IC, Ritchie S, Leighton M, Hughes AO, Bussey HJ, Morson BC (1981) Invasion of veins by carcinoma of rectum: method of detection, histological features and significance. Histopathology 5:141–163

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  7. 7.

    Talbot IC, Ritchie S, Leighton MH, Hughes AO, Bussey HJ, Morson BC (1980) The clinical significance of invasion of veins by rectal cancer. Br J Surg 67:439–442

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  8. 8.

    Brown G, Radcliffe AG, Newcombe RG, Dallimore NS, Bourne MW, Williams GT (2003) Preoperative assessment of prognostic factors in rectal cancer using high-resolution magnetic resonance imaging. Br J Surg 90:355–364

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  9. 9.

    Chand M, Swift RI, Chau I, Heald RJ, Tekkis PP, Brown G (2014) Adjuvant therapy decisions based on magnetic resonance imaging of extramural venous invasion and other prognostic factors in colorectal cancer. Ann R Coll Surg Engl 96:543–546

    CAS  PubMed  PubMed Central  Article  Google Scholar 

  10. 10.

    Ale Ali H, Kirsch R, Razaz S et al (2019) Extramural venous invasion in rectal cancer: overview of imaging, histopathology, and clinical implications. Abdom Radiol (NY) 44:1–10

    Article  Google Scholar 

  11. 11.

    Santiago I, Figueiredo N, Pares O, Matos C (2020) MRI of rectal cancer-relevant anatomy and staging key points. Insights Imaging 11:100

    PubMed  PubMed Central  Article  Google Scholar 

  12. 12.

    Nuikolouzakis TK, Mariolis-Sapsakos T, Triantopoulou C et al (2019) Detailed and applied anatomy for improved rectal cancer treatment. Ann Gastroenterol 32:431–440

    Google Scholar 

  13. 13.

    Compton CC (2002) Pathologic prognostic factors in the recurrence of rectal cancer. Clin Colorectal Cancer 2:149–160

    PubMed  Article  PubMed Central  Google Scholar 

  14. 14.

    Howlett CJ, Tweedie EJ, Driman DK (2009) Use of an elastic stain to show venous invasion in colorectal carcinoma: a simple technique for detection of an important prognostic factor. J Clin Pathol 62:1021–1025

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  15. 15.

    Sternberg A, Amar M, Alfici R, Groisman G (2002) Conclusions from a study of venous invasion in stage IV colorectal adenocarcinoma. J Clin Pathol 55:17–21

    CAS  PubMed  PubMed Central  Article  Google Scholar 

  16. 16.

    Betge J, Pollheimer MJ, Lindtner RA et al (2012) Intramural and extramural vascular invasion in colorectal cancer: prognostic significance and quality of pathology reporting. Cancer 118:628–638

    PubMed  Article  PubMed Central  Google Scholar 

  17. 17.

    van Zijl F, Krupitza G, Mikulits W (2011) Initial steps of metastasis: cell invasion and endothelial transmigration. Mutat Res 728:23–34

    PubMed  PubMed Central  Article  CAS  Google Scholar 

  18. 18.

    Merkel S, Weber K, Schellerer V et al (2014) Prognostic subdivision of ypT3 rectal tumours according to extension beyond the muscularis propria. Br J Surg 101:566–572

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  19. 19.

    Swets M, Kuppen PJK, Blok EJ, Gelderblom H, van de Velde CJH, Nagtegaal ID (2018) Are pathological high-risk features in locally advanced rectal cancer a useful selection tool for adjuvant chemotherapy? Eur J Cancer 89:1–8

    PubMed  Article  PubMed Central  Google Scholar 

  20. 20.

    MERCURY Study Group (2006) Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study. BMJ 333:779

    PubMed Central  Article  Google Scholar 

  21. 21.

    Smith NJ, Shihab O, Arnaout A, Swift RI, Brown G (2008) MRI for detection of extramural vascular invasion in rectal cancer. AJR Am J Roentgenol 191:1517–1522

    PubMed  Article  PubMed Central  Google Scholar 

  22. 22.

    Smith NJ, Barbachano Y, Norman AR, Swift RI, Abulafi AM, Brown G (2008) Prognostic significance of magnetic resonance imaging-detected extramural vascular invasion in rectal cancer. Br J Surg 95:229–236

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  23. 23.

    Koh D, Smith N, Swift R, Brown G (2008) The Relationship Between MR Demonstration of Extramural Venous Invasion and Nodal Disease in Rectal Cancer. Clin Med Oncol 2:267–273

    PubMed  PubMed Central  Google Scholar 

  24. 24.

    Sohn B, Lim JS, Kim H et al (2015) MRI-detected extramural vascular invasion is an independent prognostic factor for synchronous metastasis in patients with rectal cancer. Eur Radiol 25:1347–1355

    PubMed  Article  PubMed Central  Google Scholar 

  25. 25.

    Chand M, Evans J, Swift RI et al (2015) The prognostic significance of postchemoradiotherapy high-resolution MRI and histopathology detected extramural venous invasion in rectal cancer. Ann Surg 261:473–479

    PubMed  Article  PubMed Central  Google Scholar 

  26. 26.

    Jhaveri KS, Hosseini-Nik H, Thipphavong S et al (2016) MRI detection of extramural venous invasion in rectal cancer: correlation with histopathology using elastin stain. AJR Am J Roentgenol 206:747–755

    PubMed  Article  PubMed Central  Google Scholar 

  27. 27.

    Liu L, Liu M, Yang Z, He W, Wang Z, Jin E (2016) Correlation of MRI-detected extramural vascular invasion with regional lymph node metastasis in rectal cancer. Clin Imaging 40:456–460

    PubMed  Article  PubMed Central  Google Scholar 

  28. 28.

    Yu J, Huang DY, Xu HX, Li Y, Xu Q (2016) Correlation between magnetic resonance imaging-based evaluation of extramural vascular invasion and prognostic parameters of T3 stage rectal cancer. J Comput Assist Tomogr 40:537–542

    PubMed  Article  PubMed Central  Google Scholar 

  29. 29.

    Lee ES, Kim MJ, Park SC et al (2018) Magnetic resonance imaging-detected extramural venous invasion in rectal cancer before and after preoperative chemoradiotherapy: diagnostic performance and prognostic significance. Eur Radiol 28:496–505

    PubMed  Article  PubMed Central  Google Scholar 

  30. 30.

    Liu L, Yang L, Jin E, Wang Z, Yang Z (2016) Effect of gadolinium contrast-enhanced T1-weighted magnetic resonance imaging for detecting extramural venous invasion in rectal cancer. Abdom Radiol (NY) 41:1736–1743

    Article  Google Scholar 

  31. 31.

    Bae JS, Kim SH, Hur BY et al (2019) Prognostic value of MRI in assessing extramural venous invasion in rectal cancer: multi-readers’ diagnostic performance. Eur Radiol 29:4379–4388

    PubMed  Article  PubMed Central  Google Scholar 

  32. 32.

    Ahn JH, Kim SH, Son JH, Jo SJ (2019) Added value of diffusion-weighted imaging for evaluation of extramural venous invasion in patients with primary rectal cancer. Br J Radiol 92:20180821

    PubMed  PubMed Central  Article  Google Scholar 

  33. 33.

    Zheng K, Zheng N, Xin C et al (2020) The prognostic significance of tumor deposit count for colorectal cancer patients after radical surgery. Gastroenterol Res Pract 2020:2052561

    PubMed  PubMed Central  Google Scholar 

  34. 34.

    Zhang XY, Wang S, Li XT et al (2018) MRI of extramural venous invasion in locally advanced rectal cancer: relationship to tumor recurrence and overall survival. Radiology 289:677–685

    PubMed  Article  PubMed Central  Google Scholar 

  35. 35.

    Lambregts DMJ, van Heeswijk MM, Delli Pizzi A et al (2017) Diffusion-weighted MRI to assess response to chemoradiotherapy in rectal cancer: main interpretation pitfalls and their use for teaching. Eur Radiol 27:4445–4454

    PubMed  Article  PubMed Central  Google Scholar 

  36. 36.

    Napoletano M, Mazzucca D, Prosperi E et al (2019) Locally advanced rectal cancer: qualitative and quantitative evaluation of diffusion-weighted magnetic resonance imaging in restaging after neoadjuvant chemo-radiotherapy. Abdom Radiol (NY) 44:3664–3673

    Article  Google Scholar 

  37. 37.

    Vliegen RFA, Beets GL, von Meyenfeldt MF, Kessels AG, Lemaire EE, van Engelshoven JM, Beets-Tan RG (2005) Rectal cancer: MR imaging in local staging–is gadolinium-based contrast material helpful? Radiology 234:179–188

    PubMed  Article  PubMed Central  Google Scholar 

  38. 38.

    Gollub MJ, Lakhman Y, McGinty K et al (2015) Does gadolinium-based contrast material improve diagnostic accuracy of local invasion in rectal cancer MRI? A multireader study. AJR Am J Roentgenol 204:W160-167

    PubMed  PubMed Central  Article  Google Scholar 

  39. 39.

    Inoue A, Ohta S, Nitta N et al (2016) MRI can be used to assess advanced T-stage colon carcinoma as well as rectal carcinoma. Jpn J Radiol 34:809–819

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  40. 40.

    Beets-Tan RGH, Lambregts DMJ, Maas M et al (2018) Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting. Eur Radiol 28:1465–1475

    PubMed  Article  PubMed Central  Google Scholar 

  41. 41.

    Expert Panel on Gastrointestinal Imaging (2017) ACR appropriateness criteria((R)) pretreatment staging of colorectal cancer. J Am Coll Radiol 14:S234–S244

    Article  Google Scholar 

  42. 42.

    Krdzalic J, Maas M, Gollub MJ, Beets-Tan RGH (2019) Guidelines for MR imaging in rectal cancer: Europe versus United States. Abdom Radiol (NY) 44:3498–3507

    CAS  Article  Google Scholar 

  43. 43.

    Kim TH, Woo S, Han S, Suh CH, Vargas HA (2019) The diagnostic performance of mri for detection of extramural venous invasion in colorectal cancer: a systematic review and meta-analysis of the literature. AJR Am J Roentgenol 213:575–585

    PubMed  PubMed Central  Article  Google Scholar 

  44. 44.

    Poulsen LO, Yilmaz MK, Oddershede L et al (2018) Is the accuracy of preoperative MRI stage in rectal adenocarcinoma influenced by tumour height? Acta Oncol 57:728–734

    PubMed  Article  PubMed Central  Google Scholar 

  45. 45.

    Fornell-Perez R, Vivas-Escalona V, Aranda-Sanchez J et al (2020) Primary and post-chemoradiotherapy MRI detection of extramural venous invasion in rectal cancer: the role of diffusion-weighted imaging. Radiol Med 125:522–530

    PubMed  Article  PubMed Central  Google Scholar 

  46. 46.

    Coruh AG, Peker E, Elhan A, Erden I, Erden A (2019) Evaluation of extramural venous invasion by diffusion-weighted magnetic resonance imaging and computed tomography in rectal adenocarcinoma. Can Assoc Radiol J 70:457–465

    Article  Google Scholar 

  47. 47.

    Ortega CD, Rocha MS (2019) CT Staging To Triage Selection Of Patients With Poor-Prognosis Rectal Cancer For Neoadjuvant Treatment. AJR Am J Roentgenol 213:358–364

    PubMed  Article  PubMed Central  Google Scholar 

  48. 48.

    Wu CC, Lee RC, Chang CY (2013) Prediction of lymphovascular invasion in rectal cancer by preoperative CT. AJR Am J Roentgenol 201:985–992

    PubMed  Article  PubMed Central  Google Scholar 

  49. 49.

    Marijnen CA, van de Velde CJ, Putter H et al (2005) Impact of short-term preoperative radiotherapy on health-related quality of life and sexual functioning in primary rectal cancer: report of a multicenter randomized trial. J Clin Oncol 23:1847–1858

    PubMed  Article  PubMed Central  Google Scholar 

  50. 50.

    Kennedy ED, Simunovic M, Jhaveri K et al (2019) Safety and feasibility of using magnetic resonance imaging criteria to identify patients with “good prognosis” rectal cancer eligible for primary surgery: the phase 2 nonrandomized QuickSilver clinical trial. JAMA Oncol 5:961–966

    PubMed  PubMed Central  Article  Google Scholar 

  51. 51.

    Cho MS, Park YY, Yoon J et al (2018) MRI-based EMVI positivity predicts systemic recurrence in rectal cancer patients with a good tumor response to chemoradiotherapy followed by surgery. J Surg Oncol 117:1823–1832

    PubMed  Article  PubMed Central  Google Scholar 

  52. 52.

    Jia XX, Wang Y, Cheng J et al (2018) Low- versus high-risk rectal cancer based on mri features: outcomes in patients treated without neoadjuvant chemoradiotherapy. AJR Am J Roentgenol 211:327–334

    PubMed  Article  PubMed Central  Google Scholar 

  53. 53.

    Sclafani F, Brown G, Cunningham D et al (2016) PAN-EX: a pooled analysis of two trials of neoadjuvant chemotherapy followed by chemoradiotherapy in MRI-defined, locally advanced rectal cancer. Ann Oncol 27:1557–1565

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  54. 54.

    Chand M, Bhangu A, Wotherspoon A et al (2014) EMVI-positive stage II rectal cancer has similar clinical outcomes as stage III disease following pre-operative chemoradiotherapy. Ann Oncol 25:858–863

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  55. 55.

    Patel UB, Brown G, Machado I et al (2017) MRI assessment and outcomes in patients receiving neoadjuvant chemotherapy only for primary rectal cancer: long-term results from the GEMCAD 0801 trial. Ann Oncol 28:344–353

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  56. 56.

    Meng Y, Wan L, Ye F et al (2019) MRI morphologic and clinicopathologic characteristics for predicting outcomes in patients with locally advanced rectal cancer. Abdom Radiol (NY) 44:3652–3663

    Article  Google Scholar 

  57. 57.

    Gu C, Yang X, Zhang X et al (2019) The prognostic significance of MRI-detected extramural venous invasion, mesorectal extension, and lymph node status in clinical T3 mid-low rectal cancer. Sci Rep 9:12523

    PubMed  PubMed Central  Article  CAS  Google Scholar 

  58. 58.

    Meng Y, Wan L, Zhang C et al (2020) The predictive value of pre-/postneoadjuvant chemoradiotherapy MRI characteristics for patient outcomes in locally advanced rectal cancer. Acad Radiol 27:e233–e243

    PubMed  Article  PubMed Central  Google Scholar 

  59. 59.

    Jalil O, Afaq A, Ganeshan B et al (2017) Magnetic resonance based texture parameters as potential imaging biomarkers for predicting long-term survival in locally advanced rectal cancer treated by chemoradiotherapy. Colorectal Dis 19:349–362

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  60. 60.

    Shiraishi T, Sasaki T, Ikeda K, Tsukada Y, Nishizawa Y, Ito M (2019) Predicting prognosis according to preoperative chemotherapy response in patients with locally advanced lower rectal cancer. BMC Cancer 19:1222

    CAS  PubMed  PubMed Central  Article  Google Scholar 

  61. 61.

    Yu SKT, Tait D, Chau I, Brown G (2013) MRI predictive factors for tumor response in rectal cancer following neoadjuvant chemoradiation therapy–implications for induction chemotherapy? Int J Radiat Oncol Biol Phys 87:505–511

    PubMed  Article  PubMed Central  Google Scholar 

  62. 62.

    Chand M, Swift RI, Tekkis PP, Chau I, Brown G (2014) Extramural venous invasion is a potential imaging predictive biomarker of neoadjuvant treatment in rectal cancer. Br J Cancer 110:19–25

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  63. 63.

    Kim CH, Yeom S-S, Kwak H-D et al (2019) Clinical outcomes of patients with locally advanced rectal cancer with persistent circumferential resection margin invasion after preoperative chemoradiotherapy. Ann Coloproctol 35:72–82

    PubMed  PubMed Central  Article  Google Scholar 

  64. 64.

    Ormsby NM, Bermingham HN, Joshi HM et al (2017) The significance of extramural venous invasion in R1 positive rectal cancer. Int J Colorectal Dis 32:119–124

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  65. 65.

    Hunter CJ, Garant A, Vuong T et al (2011) Adverse features on rectal mri identify a high-risk group that may benefit from more intensive preoperative staging and treatment. Ann Surg Oncol 19:1199–1205

    PubMed  Article  PubMed Central  Google Scholar 

  66. 66.

    Bugg WG, Andreou AK, Biswas D, Toms AP, Williams SM (2014) The prognostic significance of MRI-detected extramural venous invasion in rectal carcinoma. Clin Radiol 69:619–623

    CAS  PubMed  Article  PubMed Central  Google Scholar 

  67. 67.

    Kim MJ, Park JS, Park SI et al (2003) Accuracy in differentiation of mucinous and nonmucinous rectal carcinoma on MR imaging. J Comput Assist Tomogr 1:48–55

    Article  Google Scholar 

  68. 68.

    Wnorowski AM, Menias CO, Pickhardt PJ, Kim DH, Hara AK, Lubner MG (2019) Mucin-containing rectal carcinomas: overview of unique clinical and imaging features. AJR Am J Roentgenol.

    Article  PubMed  PubMed Central  Google Scholar 

  69. 69.

    Yu SKT, Chand M, Tait DM, Brown G (2014) Magnetic resonance imaging defined mucinous rectal carcinoma is an independent imaging biomarker for poor prognosis and poor response to preoperative chemoradiotherapy. Eur J Cancer 50:920–927

    PubMed  Article  PubMed Central  Google Scholar 

  70. 70.

    Barbaro B, Leccisotti L, Vecchio FM et al (2016) The potential predictive value of MRI and PET-CT in mucinous and nonmucinous rectal cancer to identify patients at high risk of metastatic disease. Br J Radiol 90:20150836

    PubMed  PubMed Central  Article  Google Scholar 

  71. 71.

    Ozuner G, Aytac E, Gorgun E, Bennett A (2015) Colorectal squamous cell carcinoma: a rare tumor with poor prognosis. Int J Colorectal Dis 30:127–130

    PubMed  Article  PubMed Central  Google Scholar 

  72. 72.

    Nahas CS, Shia J, Joseph R et al (2007) Squamous-cell carcinoma of the rectum: a rare but curable tumor. Dis Colon Rectum 50:1393–1400

    PubMed  Article  PubMed Central  Google Scholar 

  73. 73.

    Baxi AJCK, Katkar A, Restrepo CS, Betancourt SL, Sunnapwar A (2017) Multimodality imaging findings in carcinoid tumors: a head-to-toe spectrum. Radiographics 37:516–536

    PubMed  Article  PubMed Central  Google Scholar 

  74. 74.

    Sugimoto S, Hotta K, Shimoda T et al (2016) The Ki-67 labeling index and lymphatic/venous permeation predict the metastatic potential of rectal neuroendocrine tumors. Surg Endosc 30:4239–4248

    PubMed  Article  PubMed Central  Google Scholar 

  75. 75.

    Malla S, Kumar P, Madhusudhan KS (2020) Radiology of the neuroendocrine neoplasms of the gastrointestinal tract: a comprehensive review. Abdom Radiol (NY).

    Article  Google Scholar 

Download references

Author information




AI has contributed the conception, acquisition of radiology images, analysis and interpretation data and drafting the manuscript. JGF contributed conception of the study and acquisition of radiology images. SPS, JPH, and JLF contributed conception of the study. RPG contributed acquisition of pathology images. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Akitoshi Inoue.

Ethics declarations

Ethics approval and consent to participate

Our Institutional Review Board approved that informed consent was waived as long as the patients did not decline that their data is used for any purpose except for patient care.

Consent for publication

Not applicable.

Competing interests

All authors have no conflict interest to be declared.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Inoue, A., Sheedy, S.P., Heiken, J.P. et al. MRI-detected extramural venous invasion of rectal cancer: Multimodality performance and implications at baseline imaging and after neoadjuvant therapy. Insights Imaging 12, 110 (2021).

Download citation


  • Extramural venous invasion
  • Rectal Neoplasms
  • Prognosis
  • Disease-free survival
  • Magnetic resonance imaging