Among the different pathologic structures of the presacro-coccygeal sp
ace retrorectal cystic hamartomas are uncommon lesions. These cysts ar
e most likely derived from remnants of the embryonic tail-gut although
an association to teratomas may exist. We describe the clinicopatholo
gic features of a retrorectal cystic hamartoma with malignant transfor
mation in a 60 year old female patient. The literature is reviewed and
etiology, diagnosis and operative management are discussed.