Table 2 Possible treatment modifications based on MRI after neoadjuvant therapy (MRI2) and its requirements. For discussion of different scenarios please refer to the text
From: Magnetic resonance imaging (MRI) in rectal cancer: a comprehensive review
Planned surgery after neoadjuvant therapy | ||||
|---|---|---|---|---|
No surgery or a local excision | TME | Extended TME | ||
Planned surgery before neoadjuvant therapy based on initial MRI (MRI1) | TME | Scenario A; requires: | Scenario B; no added clinical value of MRI2 | Scenario C; only if tumor progresses |
1. No remaining malignant cells | ||||
Extended TME | 2. No metastatic mesorectal lymph nodes | Scenario D; requires MRI2 to distinguish reliably that fibrosis outside mesorectum can be left alone | Scenario E; relevant only if pattern of extension to organs outside mesorectal fascia changes | |