A 57 year old Caucasian man presents with pain and bleeding from a slowly enlarging lump on his upper lip, which first appeared 1 month ago. His sister was diagnosed with colonic cancer at the age of 30, his mother with uterine cancer at age 38, and his paternal grandfather with cancer of the bladder (age unknown). He smokes regularly, with a pack history of 10 years. His job requires him to be exposed to sunlight for around 5 to 6 hours per day.
There are nests of atypical squamous cells impinging on the dermis, with an appearance compatible with squamous cell carcinoma.
Immunohistochemistry of the growth is positive, with absence of staining for the MSH-2 and MSH-6 mismatch repair proteins (MMR).
A mass lesion is seen at the hepatic flexure; a biopsy shows poorly differentiated invasive adenocarcinoma.
The CT-Urogram shows no abnormalities.