VARIANT TYPE OF TERATOMA APPEARING AS A PRIMARY SOLID DERMOID TUMOR IN THE RECTUM - REPORT OF A CASE

We report herein the rare case of a 39-year-old woman found to have a primary solid dermoid tumor in the rectum. The patient presented after noticing a small amount of anal bleeding, and physical examination re vealed a walnut-sized hard tumor, palpable in the anterior rectum, loc ated about 9 cm from the anal verge. Morphologic examinations revealed a polypoid lesion with some hair surrounded by rectal mucosa, and fou r biopsy specimens from the lesion showed normal squamous epithelium. The tumor, which measured 2.5 X 2.1 X 1.3 cm, was removed by endoscopi c polypectomy. Microscopically, the tumor was diagnosed as a solid der moid tumor without a cyst, a variant type of mature teratoma or dermoi d cyst. Since 1914, only 12 such cases, including ours, have been repo rted in Japan. The clinical features and diagnostic and therapeutic me thods applied thereto are discussed.