Prostate Type Malignancies Arising in Ovarian Teratomas – A Report of Two Patients

The identification of benign prostatic tissue within ovarian and testicular mature teratomas is an unusual occurrence. While a few documented reports exist in the literature regarding the emergence of benign prostatic tissue within teratomas, the occurrence of prostatic-type adenocarcinoma in a mature ovarian teratoma is an exceptionally rare phenomenon. To date, only two prior reports have documented such instances, and no tumors have been previously reported with prostate-type tissue with morphologically two different malignancies. We outline our experience with two tumors involving prostatic-type carcinoma, both arising in ovarian mature teratomas. Microscopic examination of the first tumor revealed small areas of infiltrative atypical glandular proliferation within the mature teratoma. In the second tumor, prostate-type tissue exhibited a low-grade basal cell carcinoma. Additionally, adjacent minute foci of adenocarcinoma of the prostate (Gleason score 3 + 4 = 7, <5% pattern 4) were identified. Goblet cell adenocarcinoma of appendiceal type was also evident in the latter tumor. In both tumors, immunostains (NKX3.1, PSA) were performed to establish the prostatic origin of these atypical glands and PIN4 was performed to document the absence of basal cell in the atypical glands. On clinical follow-up, both patients have no signs of recurrence at 14 and 11 months after the surgery. Further reports on such neoplasms would contribute to a better understanding of the prognosis and management of such occurrences.