A 20 year old female is diagnosed with granulosa cell tumor of the ovary. Which of the following biomarkers would be most useful for follow-up of patient?
**Core Concept**
Granulosa cell tumors of the ovary are sex cord-stromal tumors characterized by their production of estrogen. The management and follow-up of these tumors involve monitoring of estrogen levels, which can lead to complications such as endometrial hyperplasia and cancer.
**Why the Correct Answer is Right**
The correct biomarker for follow-up of granulosa cell tumors is inhibin B. Inhibin B is a protein produced by granulosa cells and is a marker of granulosa cell function. Inhibin B levels are often elevated in granulosa cell tumors, and monitoring these levels can help assess the response to treatment and recurrence of the tumor. Additionally, inhibin B is a sensitive marker for granulosa cell tumors, allowing for early detection of recurrence.
**Why Each Wrong Option is Incorrect**
* **Option A:** CA-125 is a tumor marker commonly used for ovarian cancer, but it is not specific for granulosa cell tumors and can be elevated in various other conditions.
* **Option B:** Human chorionic gonadotropin (hCG) is a tumor marker associated with choriocarcinoma and other germ cell tumors, but it is not typically elevated in granulosa cell tumors.
* **Option D:** Alpha-fetoprotein (AFP) is a tumor marker associated with germ cell tumors, particularly yolk sac tumors, but it is not specific for granulosa cell tumors.
**Clinical Pearl / High-Yield Fact**
It is essential to distinguish granulosa cell tumors from other ovarian tumors, as they have distinct clinical and pathological features. Granulosa cell tumors are often associated with young women, and they can produce estrogen, leading to complications such as endometrial hyperplasia and cancer.
**Correct Answer:** C. Inhibin B.