PMC6577306_01
Immunohistochemical staining of the mismatch repair proteins in the patient's tumours. (A-E) Endometrial adenocarcinoma: H&E staining (A), with intact MLH1 (B) and pms2 (C), and dual loss of MSH2 (D) and MSH6 (E) immunostaining in tumour cell nuclei. (F-J) Colonic adenocarcinoma: H&E staining (F), with intact MLH1 (G) and pms2 (H), and dual loss of MSH2 (I) and MSH6 (J) immunostaining in tumour cell nuclei. (K-O) High-grade papillary urothelial carcinoma: H&E staining (K), with intact MLH1 (L) and pms2 (M), and dual loss of MSH2 (N) and MSH6 (O) immunostaining in tumour cell nuclei. (P-T) Pancreatic ductal adenocarcinoma: H&E staining (P) with intact MLH1 (Q), pms2 (R), MSH2 (S) and MSH6 (T) immunostaining in tumour cell nuclei. All photomicrographs taken at x400 magnification.
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F1
Surprisingly, the pancreatic cancer showed intact protein staining of all four MMR proteins, including MSH2 and MSH6 (figure 1).
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