In approximately 1÷3 of the hyperplastic polyps and serrated adenomas, we noted that the decrease in expression of MSH2 is associated with an increase in the expression of p53, c-myc, Ki-67, and Ets-1.
Polyps coded as hyperplastic polyps (HP) from subjects with Lynch syndrome and FCF enrolled in the HNPCC-register at the Hvidovre University Hospital as well as adenomas from this population were retrieved and reviewed for features of SSP.
Mixed polyps, particularly those with carcinoma, showed loss of hMLH1 (33%), MGMT (37%), and even hMSH2 (11%) with significantly higher frequency compared to hyperplastic polyps, conventional adenomas, and serrated adenomas.