Dome-Type : A Distinctive Variant of Colonic Adenocarcinoma

Abstract EN

Introduction.

Ten cases of dome-type adenocarcinoma of the colon have been reported so far.

Most of them were presented as early lesions, with endoscopic and microscopic distinguishing features.

Methods and Results.

A raised plaque was removed from the right colon during colonoscopy in a 56-year-old man.

Histopathological examination showed a cancerized adenoma invading the submucosa with several typical features of dome-type adenocarcinoma, in particular the associated prominent lymphoid tissue.

Immunohistochemistry showed retention of the mismatch repair proteins MLH-1, MSH-2, MLH-6, and PMS-2.

Conclusion.

We report an additional case of dome-type adenocarcinoma of the colon as an early, low-risk, and microsatellite stable tumor, indicating that this particular histotype may deserve specific consideration for both classification and management.