Step 1 topics → Reproductive → Sex-Cord Stromal Ovarian Tumors

Sex-Cord Stromal Ovarian Tumors

USMLE Step 1 trap: Confuses Call-Exner bodies with thecoma due to shared estrogen production. Call-Exner bodies (follicle-like rosettes) are the histologic hallmark of granulosa cell tumors, not thecoma.

Sex-cord stromal tumors are a functionally active group of ovarian neoplasms — they make hormones, and USMLE Step 1 exploits that. The three you need cold are granulosa cell tumors (estrogen), Sertoli-Leydig tumors (androgens), and ovarian fibromas (no hormones, but a classic triad). The most common trap is assigning Call-Exner bodies to thecomas, when those follicle-like rosettes belong exclusively to granulosa cell tumors. The exam gives you a clinical vignette and asks you to connect the hormone output to the presentation — postmenopausal bleeding, virilization, or a suspicious pleural effusion — then identify the tumor type or its histologic hallmark.

The tricky part is that students often conflate these tumors because they're all grouped under 'sex-cord stromal' and some share superficial features. Granulosa cell tumors and thecomas both produce estrogen, so students incorrectly assign Call-Exner bodies to thecoma. Sertoli-Leydig tumors get flipped to estrogen-producing because students pattern-match 'Sertoli' to 'Leydig' to 'testis' to 'sex hormones' without pinning down which sex hormone. These are exactly the confusions that USMLE Step 1 is designed to catch.

Meigs syndrome is tested as a pure recall-and-apply problem — the exam gives you ovarian fibroma plus one or two components of the triad and asks what else is present or what happens after resection. Students who only memorize 'fibroma + ascites' will miss the right-sided pleural effusion and get it wrong. Know all three components and know that they resolve with tumor removal.

From real student decks
62%have cards covering this topic
41%have mature cards
1median lapses in 14 days

Common misconceptions

Common mistake
Wrong: Call-Exner bodies are produced by thecoma because both tumors produce estrogen.
Right: Call-Exner bodies (follicle-like rosettes) are the histologic hallmark of granulosa cell tumors, not thecoma.
Thecomas and granulosa cell tumors both produce estrogen, but they are histologically distinct. Call-Exner bodies are follicle-like rosettes formed specifically by granulosa cells — they are the defining microscopic feature of granulosa cell tumors, not thecomas. When you see 'Call-Exner bodies' on the exam, the answer is granulosa cell tumor, full stop.
Common mistake
Wrong: Granulosa cell tumors are clinically silent in postmenopausal women.
Right: Granulosa cell tumors produce estrogen and cause postmenopausal bleeding and endometrial hyperplasia in older women.
Granulosa cell tumors are anything but clinically silent in postmenopausal women — they are one of the classic causes of postmenopausal uterine bleeding because they keep producing estrogen after the ovaries have stopped. That unopposed estrogen drives endometrial hyperplasia, which can progress to carcinoma. Any postmenopausal woman with an ovarian mass and uterine bleeding should make you think granulosa cell tumor.
Common mistake
Wrong: Sertoli-Leydig tumors produce estrogen and cause feminization.
Right: Sertoli-Leydig tumors produce androgens and cause virilization (hirsutism, clitoromegaly, amenorrhea).
Despite being an ovarian tumor, Sertoli-Leydig tumors recapitulate testicular cell types and secrete androgens, not estrogen. The clinical result is virilization — hirsutism, clitoromegaly, deepening voice, and amenorrhea. If the vignette describes a woman with an ovarian mass who is becoming more masculine, that is your cue: Sertoli-Leydig tumor, androgens, virilization.
Common mistake
Wrong: Meigs syndrome consists of ovarian fibroma with ascites alone.
Right: Meigs syndrome is the triad of ovarian fibroma, ascites, and right-sided pleural effusion, all resolving after tumor removal.
Meigs syndrome is a triad, and all three components must be memorized together: ovarian fibroma, ascites, and right-sided pleural effusion. The pleural effusion is the component students drop. The mechanism involves fluid tracking from the peritoneum through diaphragmatic lymphatics, with preferential right-sided accumulation. Critically, all three findings resolve completely after surgical resection of the fibroma — this is a high-yield detail the exam loves to test.
Free Deck audit

See if your Anki deck covers this topic.

Upload your deck →
Guided session

Stuck on this? An AI tutor that probes your understanding.

Start a session →

What the exam tests

  1. Given a patient with an ovarian mass, identify that granulosa cell tumors produce estrogen, and connect that to age-specific effects: precocious puberty in girls, irregular bleeding in reproductive-age women, and postmenopausal bleeding with endometrial hyperplasia in older women.
  2. Recognize Call-Exner bodies — follicle-like rosettes of granulosa cells surrounding eosinophilic material — as the specific histologic hallmark of granulosa cell tumors, not thecomas (which also make estrogen but have a different histology).
  3. Identify Sertoli-Leydig tumors as androgen-secreting tumors that cause virilization: hirsutism, clitoromegaly, deepened voice, and amenorrhea — not feminization.
  4. Recall the complete Meigs syndrome triad — ovarian fibroma, ascites, and right-sided pleural effusion — and know that all three resolve after surgical removal of the tumor.

Can you avoid these mistakes?

A 62-year-old woman presents with vaginal bleeding. Pelvic ultrasound shows an ovarian mass; endometrial biopsy shows hyperplasia. What tumor type is most likely, what hormone does it produce, and what histologic structure would you expect to see on pathology?
A 28-year-old woman develops progressive hirsutism, amenorrhea, and clitoromegaly over 6 months. Imaging reveals a small ovarian mass. What is the tumor, and what hormone is it secreting?
A 55-year-old woman has a solid right ovarian mass, ascites, and a right pleural effusion. What is the diagnosis, and what happens to the ascites and pleural effusion after the mass is removed?
A pathology slide shows an ovarian tumor with small cells arranged in rosettes around a central eosinophilic material. Which tumor does this histology represent, and which other estrogen-producing ovarian tumor does NOT show this finding?

Related topics

Gonadal Differentiation (SRY, MIS, Testosterone) Müllerian vs Wolffian Duct Derivatives 5α-Reductase Deficiency Complete Androgen Insensitivity Syndrome (CAIS)

See how your Anki deck covers this topic.

Upload your deck for a free audit →