Prostatic tissue in mature cystic teratomas of the ovary

We report two examples of mature cystic teratomas of the ovary containing prostatic tissue. Both were incidental findings in teratomas that were otherwise typical at clinical and pathologic levels. The prostatic tissue contained ducts and acini in a simple branching pattern similar to that seen in the peripheral zone of the prostate gland. Transitional cell elements were present in both cases and compact acini resembling Cowper's gland were noted in one. No testicular or Wolffian duct tissue was noted. The immunohistochemical staining pattern of the glands was identical to that seen in normal prostate. In a literature review, four additional cases were identified. The presence of prostatic tissue in a 46XX tumor suggests induction by locally produced androgen. Some investigators have identified luteinized stromal cells and indicated these as the source of this androgen. Other possible androgenic origins include ovarian hilar cells, adrenal cortex, and tumor cells.