This image shows analysis of mismatch repair (MMR) genes in a sebaceous adenoma by immunohistochemistry. There is isolated loss of MSH6 expression in the tumor. MSH2, MLH1, and PMS2 are positive by immunohistochemistry. Further discussion of the role MMR genes in sebaceous neoplasms is in the section on Muir-Torre Syndrome. Image courtesy of: Sate Hamza, MD, Asst. Professor of Pathology, University of Manitoba, Winnipeg, Manitoba, Canada; Used with permission.