Adrenocortical carcinoma, an unusual extracolonic tumor associated with Lynch II syndrome

Lynch syndrome (LS) is an autosomal dominant condition that predisposes to colorectal cancer and specific other tumors. Extracolonic tumors occur mainly in the endometrium, stomach, ovary, small intestine and urinary tract. The presence of rare tumors in patients belonging to families who have Lynch syndrome is always interesting, because the question arises whether these tumors should be considered as a coincidence or are related with the syndrome. In this last case, they are also the result of the defect in the mismatch repair system, opening the possibility of extending the tumor spectrum associated with the syndrome. Here we describe a patient from a Lynch syndrome family with a germline mutation c.2063T>G (p.M688R) in the MSH2 gene, who developed an adrenal cortical carcinoma, a tumor not usually associated with LS. We analyzed the adrenocortical tumour for microsatellite instability (MSI), LOH and the presence of the germline c.2063T>G (M688R) mutation. The adrenal cortical carcinoma showed the MSH2 mutation, loss of heterozygosity of the normal allele in the MSH2 gene and loss of immunohistochemical expression for MSH2 protein, but no microsatellite instability. Additionally, the adrenal cortical carcinoma did not harbour a TP53 mutation. The molecular study indicates that this adrenal cortical cancer is probably due to the mismatch repair defect.