Gonadoblastoma. Immunohistochemical and ultrastructural observations.

Gonadoblastoma is an unusual tumor that typically arises in a streak gonad or an abnormal testis of an individual having a Y chromosome. It is a mixed tumor composed of primitive germ cells and sex cord cells arranged in characteristic nests containing hyaline material. Whether the supportive gonadal sex cord cells are granulosa or Sertoli cells has not been clearly established, but one prior ultrastructural study favored Sertoli cell differentiation.

The differential diagnosis of yolk sac tumor and seminoma. Usefulness of cytokeratin, alpha-fetoprotein, and alpha-1-antitrypsin immunoperoxidase reactions.

Yolk sac tumor and seminoma may have a similar appearance in focal areas. Small biopsies may therefore be difficult to interpret. The authors studied 20 yolk sac tumors and 21 seminomas to investigate the utility of immunohistochemical markers in this differential diagnosis.

Glycogen-rich clear cell carcinoma of the urethra: an ultrastructural study.

A 49-year-old black woman developed a urethral glycogen-rich clear cell carcinoma. She was treated with anterior pelvic exenteration. The resected lymph nodes, vagina, uterine cervix, endometrium, ovaries, and urinary bladder were free of neoplasm.