Figure 2.

Pathohistological features of proband’s (III-1) tumor; adenocarcinoma of the cecum. (A) Histological analysis (hematoxylin and eosin) revealed a poorly differentiated adenocarcinoma of the cecum, consisting of poorly formed glands and sheets of cells with large vesicular nuclei and prominent nucleoli. (B–E) Immunohistochemical staining of tumor cells showed retained expression of MLH1 (B), MSH2 (C) and MSH6 (D), and loss of expression (staining) of PMS2 (E). Note that PMS2 staining was lost in tumor cells, while internal control (stromal cells, immune cells) have intact PMS2 expression.