Clinicopathological features and evaluation of microsatellite stability of colorectal carcinoma with cribriform comedo pattern

Background: Cribriform comedo‑type adenocarcinoma (CCA) was a colo cancer subtype defined in the 2009 World Health Organization (WHO classification. In the 2018 classification, it was a colon cancer subtype include in the adenocarcinoma, Not otherwise specified (NOS) group. A few studie have reported that colon cancers with a cribriform pattern have worse overa survival, and most of them are microsatellite stable (MSS). In this study, w evaluated CCAs based on their clinicopathologic features and microsatellit stability. We aimed to answer whether these tumors could be defined as distinct morphologic subtype with prognostic significance. Materials an Methods: Pathology reports and specimens from 449 patients with colorect adenocarcinoma (CRA) were re‑evaluated. All subtypes were determined. T evaluate MSS status, the CCA cases were immunohistochemically stained wit anti‑MLH1, MSH2, MSH6, and PMS2 antibodies. Results: CCA was present i 40.5% of cases. These cases were found to have higher rates of lymph nod metastasis, lymphovascular‑perineural invasion, metastasis, and advance stage (P < 0.05). Also, 2.7% of CCA cases were microsatellite instable (MSI However, no statistically significant result was found regarding overall surviv and progression‑free survival of CCA cases with MSI. Conclusion: Accordin to the findings, CRAs with comedo cribriform patterns are tumors with mor aggressive features. It can be said that these tumors have a specific molecula feature related to MSS. Because this feature is important for planning adjuva chemotherapy, it may be useful to identify cases, particularly with a cribrifor comedo pattern >90%. However, because no significant difference in surviv rates was found, CCAs may not need to be defined as distinct subtypes.