Choriocarcinoma

Choriocarcinoma is a malignant, trophoblastic and aggressive cancer, usually of the placenta. It is characterized by early hematogenous spread to the lungs. It belongs to the far end of the spectrum of gestational trophoblastic disease (GTD), a subset of germ cell tumors.

Pathology
Characteristic feature is the identification of intimately related syncytiotrophoblasts and cytotrophoblasts without formation of definite placental type villi.

Syncytiotrophoblasts are large cells with bizarre nuclei and an eosinophilic cytoplasm. They often surround the cytotrophoblasts.

Cytotrophoblasts are polyhedral and regular cells. Have a clear/eosinophillic cytoplasm with hyperchromatic nuclei. It's also Chorion associated with the uterus.

Etiology/Epidemiology
Choriocarcinoma of the placenta during pregnancy is preceded by:
 * hydatidiform mole (50% of cases)
 * Spontaneous abortion (20%of cases)
 * ectopic pregnancy (2% of cases)
 * normal term pregnancy (20-30% of cases)

Rarely, choriocarcinoma occurs in primary locations other than the placenta; very rarely, it occurs in testicles. Although trophoblastic components are common components of mixed germ cell tumors, pure choriocarcinoma of the adult testis is rare. Pure choriocarcinoma of the testis represents the most aggressive pathologic variant of germ cell tumors in adults, characteristically with early hematogenous and lymphatic metastatic spread. Because of early spread and inherent resistance to anticancer drugs, patients have poor prognosis. Elements of choriocarcinoma in a mixed testicular tumor have no prognostic importance.

It can also occur in the ovaries.

Symptoms/Signs/Labs

 * increased quantitative &beta;-hCG levels
 * vaginal bleeding
 * shortness of breath
 * hemoptysis (coughing up blood)
 * chest pain
 * chest X-ray shows multiple infiltrates of various shapes in both lungs
 * presents in males as a testicular neoplasm, sometimes with skin hyperpigmentation (from excess beta hCG cross reacting with the alpha MSH receptor), gynecomastia, and weight loss (from excess beta hCG cross reacting with the TSH receptor) in males
 * can present with increased TSH

Treatment
Choriocarcinoma is one of the tumors that is most sensitive to chemotherapy. The cure rate, even for metastatic choriocarcinoma, is around 90-95%. Virtually everyone without metastases can be cured; however, metastatic disease to the liver and/or brain is usually fatal. At present, treatment with single-agent methotrexate or actinomycin D is recommended for low-risk disease, while intense combination regimens including EMACO (etoposide, methotrexate, actinomycin D, cyclosphosphamide and vincristine (Oncovin)) are recommended for intermediate or high-risk disease.

Hysterectomy (surgical removal of the uterus) can also be offered to patients > 40 years of age or those for whom sterilisation is not an obstacle. It may be required for those with severe infection and uncontrolled bleeding.