Morphology and immunohistochemical studies of ovarian strumal carcinoid

Teratomas are tumors derived from pluripotent germ cells, and they appear most frequently in ovaries. Strumal carcinoid belongs to the group of monodermal teratomas. Strumal carcinoid is characterized by the presence of carcinoid tumor, intermingled with thyroid tissue. A 52-year-old postmenopausal woman was referred to the Department of Gynecology and Obstetrics, Clinical Center of Vojvodina, Novi Sad with complex right adnexal mass for surgery. Laparotomy revealed tumor arising from the right ovary, of firm consistency and intact capsule. On gross examination, yellowish brown tumor was 26 x 17 x 10 cm, with vague nodularity. The cut sections revealed predominantly solid mass with two cystic areas, and one of the cysts showed a tuft of hair. On histopathological examination, the cystic spaces were lined with skin and mucinous epithelium. The solid areas showed a population of monomorphic cells with eosinophilic cytoplasm and nuclei with "salt and pepper" chromatin, arranged in acinar and trabecular patterns, respectively. In addition, focally follicular structures with central eosinophilic colloid-like material were seen. Based on the presence of these two components, a diagnosis of Strumal Carcinoid was made and confirmed on immunohistochemistry. The tumor cells were diffusely immunopositive for synaptophysin, chromogranin, and the follicles including the central coIloid were immunopositive for thyroglobulin and Thyroid transcription factor-1. Neither proliferative or mitotic activity nor capsular or angiolymphatic invasion were noticed. At 3 year follow up the patient was disease free. In order to diagnose this rare tumor a team, consisting of a pathologist, surgeon and radiologist, is needed. Diagnosis of strumal carcinoid has to be confirmed on immunohistochemistry.