Sebaceous carcinoma arising in mature cystic teratoma of ovary

Abstract

Roughly 1% of mature cystic teratomas undergo malignant transformation. In particular, cutaneous-type adnexal neoplasms may occur in mature cystic teratomas. Sebaceous carcinomas, which arise from mature cystic teratomas, have rarely been observed, with only seven cases previously reported. Here, we present a case of a 69-year-old female who had pelvic pain for two weeks and who subsequently underwent bilateral salpingo-oophorectomy and hysterectomy. Her left ovary showed a unilocular cyst, measuring 22.0 cm in diameter, filled with sebaceous material and a few hairs. A luminally-protruding solid mass measuring 4.0 cm in diameter was also noted. Microscopic findings revealed lobular or diffusely arranged basophilic, atypical sebaceous cells connected to a typical mature cystic teratoma. Tumor cells demonstrated positive immunoreactivity for high molecular weight cytokeratin, cytokeratin 7, cytokeratin 19, epithelial membrane antigen, and carcinoembryonic antigen. Here, we present a case of sebaceous carcinoma arising from a mature cystic teratoma along with a review of previously published reports.

Keywords: Mature cystic teratoma; Ovary; Sebaceous adenoma; Sebaceous carcinoma.

Fig. 1

Overall findings of the left ovary demonstrate a unilocular cyst filled with keratin-like material. A luminally-protruding (arrow head) and outer, expanding mass measuring 6.0 cm is noted. The cut surface of the mass is relatively grayish-white and firm in the luminal portion and was tan-colored and friable with hemorrhagic necrosis in the outer, expanding region.

Fig. 2

Microscopically, the luminally-protruding portion exhibits a nodular arrangement of germinative cells with a pushing border that is abruptly connected to a stratified squamous epithelium of a mature cystic teratoma. Beneath the nodular portion, sheets or nests of infiltrating atypical cells are noted.

Fig. 3

(A) Infiltrating cells arranged in trabeculae or nests that are focally contiguous to the inner, nodular portion with similar cytologic features. (B) Infiltrating cells show conspicuous vacuoles in the cytoplasm along with remarkable nuclear pleomorphism, prominent nucleoli, and frequent abnormal mitoses.

Fig. 4

Cytoplasm of tumor cells reveals immunohistochemically-positive reaction for cytokeratin 7 (A), epithelial membrane antigen (B), carcinoembryonic antigen (C), and nuclear positive reaction for p63 (D).