Leiomyomata and Leiomyosarcomata of the Rectum and Anal Canal

Abstract

The first detailed report of a rectal smooth muscle tumour is attributed to Carlier and Vander Espt in 1881 [1]. Many cases have been reported subsequently, but nevertheless these lesions remain uncommon, especially when compared with the very much more common rectal carcinoma. In 1950, Anderson et al. [2] reviewed the cases seen at the Mayo Clinic and found only 10 cases of leiomyoma and 10 cases of leiomyosarcoma of the rectum during a 35-year period (1911–1946). Somervell and Mayer [3] calculated from the Cancer Registry of the Birmingham region (1950–1965) that smooth muscle tumours made up only 0.08% of all rectal tumours. Smooth muscle tumours arising from the internal sphincter of the anal canal are even rarer than those arising from the rectum [4].