MLH1 and Lynch syndrome: In an immunohistological study of expression of mismatch repair gene-encoded proteins (hMLH1, hMSH2, hMSH6, and PMS2), Garg et al. found carcinoma of the LUS in 5 of 32 patients with reduced protein expression, but only in 1 of 39 with normal protein expression, indicating an association between carcinoma of the LUS and Lynch syndrome [28].