ABSTRACT
Authors experienced a rare adenocarcinoma arising in presacral sacrococcygeal teratoma in a adult and herein reported. The patient was a 52 year old female admitted because of lower abdominal pain for 5 to 6 months. Past and familial history were unremarkable. On rectal examination a mass was palpated 3 cm above the anal verge. The large bowel was displaced by an extrinsic mass but there was no evidence of intrinsic tumor lesion on barium enema, CT was done and showed a large presacral tumor attached to the sacrum. Clinical impression was sacrococcygeal teratoma. Resected tumor mass was a relatively well circumscribed cystic mass, measuring 11 x 11 cm and the cystic content was previously evacuated. Inner surface showed ragged appearance, and focal nodular solid area was noted. On microscopic examination, the tumor revealed the derivatives of three germ layers and main components were tissues of respiratory tract. Sections from the solid area showed a well differentiated adenocarcinoma and with stromal, capsular and perineural invasion. Borderline malignant epithelial lesions are also noted suggesting the pathogenesis and progression of this tumor. There was no recurrence for one year after surgery in the follow up.