Squamous cell carcinoma arising in mature cystic teratoma: a rare case.

Introduction: Germ cell tumors account for approximately 30% of all ovarian tumors. Ninety-five percent of germ cell tumors are dermoid cyst (mature cystic teratoma). It is composed of mature tissues derived from 3 germ cell layers (ectoderm, mesoderm, and endoderm). Malignant transformation in a mature cystic teratoma of the ovary is a rare event, developing in 1 to 2 % of cases and is associated with a poor prognosis. It occurs mostly in post menopausal females. The most common malignancy is squamous cell carcinoma (75%), followed by adenocarcinoma and melanoma. Case Report: In the present case, a patient presented with complaints of pain abdomen and abdominal distension since 2 months. USG and CT scan revealed large multinucleated solid cystic mass likely solid ovarian malignancy.CA 125 was within normal limits. On Laprotomy, there was big abdominal pelvic mass adherent to gut loops. Left ovary was replaced with this big cystic mass. On debulking of cystic growth, pus admixed with blood was present. On histopathological examination, keratinizing squamous cell carcinoma arising in mature cystic teratoma with invasion into myometrium was diagnosed. Summary and Conclusion: SCC arising from a mature cystic teratoma is a rare pathologic event and in most instances not diagnosed preoperatively. There are no particular signs or symptoms which are characteristic of malignancy arising in a dermoid cyst. The risk factors for malignancy in mature cystic teratoma include age and tumor size. The patients with metastasis have a very poor prognosis.