USMLE Step 1 · Reproductive

Epithelial ovarian cancer vs Germ cell and sex-cord stromal ovarian tumors

How to tell Epithelial ovarian cancer and Germ cell and sex-cord stromal ovarian tumors apart when a board question makes them look alike.

Fastest separator

Epithelial ovarian cancer is older and peritoneal/CA-125; germ cell is younger with AFP, LDH, or high hCG by subtype; sex-cord stromal is hormone/inhibin driven.

Side by side

Epithelial ovarian cancerGerm cell and sex-cord stromal ovarian tumors

Key clue

Epithelial ovarian cancers usually occur in older patients and present late with bloating, ascites, omental spread, and often elevated CA-125.

Germ cell tumors often affect younger patients and may secrete AFP, LDH, or hCG depending on subtype; sex-cord stromal tumors can secrete estrogen, androgens, or inhibin.

Mechanism

Epithelial tumors arise from ovarian surface, tubal-type, mucinous, endometrioid, clear cell, or related epithelium.

Germ cell tumors differentiate toward embryonic or extraembryonic tissues; sex-cord stromal tumors arise from granulosa, theca, Sertoli, or Leydig elements.

Labs and tests

CA-125, papillary serous histology, psammoma bodies, ascites, and peritoneal implants support epithelial disease.

AFP supports yolk sac or embryonal elements, LDH supports dysgerminoma, markedly elevated hCG supports choriocarcinoma, and inhibin supports granulosa cell tumor.

The trap

All are ovarian masses, so age, tumor marker, histology, and hormone effects separate them.

The repair move

For ovarian masses, pair patient age with tumor marker and histology: (1) older postmenopausal woman plus elevated CA-125 plus peritoneal carcinomatosis equals epithelial ovarian cancer (serous, mucinous, endometrioid, or clear cell histology; serous is most common and carries BRCA1/2 risk); (2) younger reproductive-age woman plus elevated AFP and beta-hCG and LDH equals germ cell tumor (dysgerminoma like a male seminoma, yolk sac with Schiller-Duval bodies and AFP, embryonal carcinoma, immature teratoma); (3) hormonally active mass equals sex-cord stromal tumor (granulosa cell tumor secretes estrogen causing post-menopausal bleeding or precocious puberty plus Call-Exner bodies on histology, plus elevated inhibin; Sertoli-Leydig cell tumor secretes androgens causing virilization).

Try a free question

Core

A 67-year-old postmenopausal woman has 5 months of abdominal bloating and a 4 kg weight loss. CT shows a 9 cm complex adnexal mass with solid and cystic components, ascites, and omental caking. CA-125 is 620 U/mL. Biopsy shows papillary architecture with psammoma bodies. Which diagnosis is most likely?

Show answer and explanation

Answer: A. Serous epithelial ovarian carcinoma. Serous epithelial ovarian carcinoma is the most common ovarian malignancy in older women; psammoma bodies, papillary architecture, omental caking, and CA-125 elevation are characteristic.

Why the other choices are tempting

B. Dysgerminoma occurs in younger women with elevated LDH, not in 67-year-olds with psammoma bodies.
C. Yolk sac tumor secretes AFP and occurs in younger patients, not psammoma-body epithelial disease in older women.
D. Granulosa cell tumor secretes estrogen and inhibin, causing postmenopausal bleeding from endometrial hyperplasia rather than papillary serous histology.
E. Mature cystic teratoma is benign and contains hair, teeth, and sebaceous material, not papillary serous malignancy.

Flashcards

Tap a card to flip it.

What marker often tracks epithelial ovarian cancer?

CA-125 often tracks epithelial ovarian cancer burden.

What marker supports yolk sac tumor?

AFP supports ovarian yolk sac tumor.

Quick answers

What is the fastest way to tell Epithelial ovarian cancer from Germ cell and sex-cord stromal ovarian tumors?