Squamous carcinoma of the foot arising in association with long-standing verrucous hyperplasia in a patient with congenital lymphedema.

A patient is reported with congenital lymphedema who developed a squamous cell carcinoma on his affected foot. Parallels are drawn between the development of a squamous cell carcinoma with condylomatous and spindle cell features arising in a setting of long-standing verrucous hyperplasia, as seen in this patient, and the well-recognized phenomenon of angiosarcoma occurring in areas of lymphangiomatous proliferation in patients with chronic lymphedema. The importance of a random genetic mutation occurring in hyperplastic tissue in an immunologically privileged site is discussed. Additional consideration is given, in the current case, to the possibility of viral oncogenesis and the role of ulceration as a promoter factor.