## **Core Concept**
Choriocarcinoma is a type of gestational trophoblastic neoplasia (GTN) characterized by the presence of high levels of human chorionic gonadotropin (hCG) and a high propensity for metastasis. It is a malignant tumor that requires prompt and effective treatment. The treatment approach for choriocarcinoma depends on the stage, risk factors, and overall health of the patient.

## **Why the Correct Answer is Right**
The correct answer, **Methotrexate and folinic acid (or Actinomycin D)**, is considered the first-line treatment for low-risk gestational trophoblastic neoplasia, including choriocarcinoma. Methotrexate is a folate antagonist that inhibits dihydrofolate reductase, an enzyme necessary for DNA synthesis and cell replication. Folinic acid (leucovorin) is used to rescue normal cells from methotrexate toxicity. Actinomycin D is an alternative or adjunct agent, especially in cases of methotrexate resistance or high-risk disease. This combination is effective in treating choriocarcinoma by targeting rapidly dividing cells.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because while surgery may be necessary in some cases of choriocarcinoma (e.g., for an isolated resistant focus or in emergency situations like hemorrhage), it is not the primary treatment for choriocarcinoma, which often presents with widespread disease.
- **Option B:** This option is incorrect as hysterectomy alone would not address potential micrometastases and is generally reserved for specific indications, such as in older women who do not desire future fertility or in cases of severe bleeding.
- **Option C:** This option is incorrect because, although radiotherapy may be used in selected cases (e.g., brain or liver metastases), it is not the treatment of choice for choriocarcinoma.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that the FIGO (International Federation of Gynecology and Obstetrics) scoring system is used to stratify patients with gestational trophoblastic neoplasia into low-risk and high-risk categories, which guides treatment decisions. For low-risk GTN, including many cases of choriocarcinoma, methotrexate or actinomycin D as single agents are often effective.

## **Correct Answer:** . Methotrexate and folinic acid (or Actinomycin D)