Fig. 16

Tumor regrowth with an appearance that is different from the initial tumor in a 72-year-old male patient with mucinous right colon cancer and liver metastases. The patient received 12 cycles of FOLFOX with an objective response. Preoperative MR imaging was performed after right portal vein embolization and after discontinuation of chemotherapy for 8 weeks and showed a mucinous metastasis with a peripheral, focal, non-mucinous glandular proliferation. The initial mucinous metastasis was seen medially (arrowheads) with high signal intensity on fast spin echo T2-weighted images (a) and a central high apparent diffusion coefficient (ADC) (b). The focal regrowth was seen laterally (arrows) with mild signal intensity on fast spin echo T2-weighted image (a) and diffusion restriction with a low ADC (b). Gross pathology (c) confirmed the presence of a metastasis of mucinous adenocarcinoma (arrowhead) with non-mucinous focal regrowth (arrow)