Mucinous adenocarcinoma arising from fistula in ano: MRI findings

The purpose of this study was to describe MRI findings in 11 patients with mucinous adenocarcinomas arising from fistula in ano.

More than half of patients had a mass filled with markedly hyperintense content on T2-weighted fast spin-echo images, enhancing solid components within the mass, mesh-like internal enhancement, fluid collections without a thick fibrous capsule, contrast enhancement of peritumoral areas, and a fistula between the mass and the anus. Regional areas of lymph node enlargement were considered indirect findings of locally advanced mucinous adenocarcinoma. These MRI findings may help diagnose mucinous adenocarcinomas arising from fistula in ano.