One of my colleagues received a 40-cm left colectomy specimen from a 49-year-old woman that I diagnosed with a grade 1 T3N0 cecal adenocarcinoma in August of 2011. MMR testing by IHC at that time showed proficient (or intact) MMR proteins. The specimen contained around 20 or so separate and discrete polyps with a range of sizes (0.4 to 1.5 cm) and configurations (pedunculated to sessile)--but none which appeared grossly canacerous.
We consulted our trusted tomes and PubMed but were unable to find any published protocols for what constitutes even "adequate" sampling for colectomy specimens resected for polyposis. Is anyone out there aware of such a protocol?
My colleague (wisely) decided to sample all the sessile and/or >1 cm polyps. As it turned out, a T1 adenocarcinoma was identified in one such polyp and a Tis lesion in another. Lymph nodes were negative but, I would add, the surgery was performed laparoscopically and the mesenteric cuff was (ahem) abbreviated.