Shia et al. [28] analyzed the IHC staining patterns for MLH1, MSH2, MSH6 and PMS2 in the matched biopsy and resection samples in 70 carcinomas of the tubular gastrointestinal tract and confirmed that biopsy samples were as reliable as resection samples in predicting mismatch repair protein abnormality. Here, PMS2 is linked to carcinoma.