Choriocarcinoma

Choriocarcinoma is a rare and aggressive form of tumor that develops in trophoblast cells (a part of the placenta which provides nutrition to the embryo). There are two main types of choriocarcinoma: gestational and non-gestational. Choriocarcinoma mostly affects women, but it can also happen to men, usually as part of a mixed germ cell tumor.

Last Updated: September 27, 2023

The incidence of choriocarcinoma varies widely among regions. In Southeast Asia and Japan, 9.2 out of every 40,000 pregnant women and 3.3 out of every 40 people with hydatidiform moles will later develop choriocarcinoma.

Choriocarcinoma can also happen in men, most often in those between 20 and 30 years old. Less than 1% of all tumors in the testicles are pure choriocarcinoma.

Choriocarcinoma develops when placenta cells become malignant. It can occur after a miscarriage, abortion, ectopic pregnancy, or molar pregnancy, when a fertilized egg develops into a mass of cysts instead of a fetus.

The uterus may bleed because of choriocarcinoma. Abdominal pain or pressure could be experienced if the cancer has spread there. A woman may have the symptoms below if the cancer has progressed to the brain or lungs:

  • Cough
  • Difficulty breathing
  • Pain in the chest
  • Headache

Elevated human chorionic gonadotropin (hCG) levels can cause a variety of symptoms, including gynecomastia in men and irregular uterine bleeding in women.

It is more common for men to exhibit symptoms of metastatic disease, such as hemoptysis, but the liver, gastrointestinal tract, and brain are also common sites of involvement.

Complete blood count (CBC), coagulation studies, body chemistry, renal function panels, liver function panels, type and screen, and quantitative hCG are just a few of the many laboratory tests that may be evaluated for choriocarcinoma. When the disease becomes aggressive and metastatic, doctors will monitor the following:

  • Increase of hCG levels after uterus removal;
  • Bleeding vaginal bleeding;
  • Internal bleeding;
  • Choriocarcinoma histology;
  • Brain, liver, GI metastases;
  • > 2-cm lung opacities via chest x-ray;
  • 4 weeks after evacuation of cancerous placenta, serum hCG >20,000 IU/L
  • Elevated hCG greater than 6 months after evacuation even when decreasing

Treatment

Treatment of choriocarcinoma is based on staging. Low-risk (stage I to III) choriocarcinoma can be treated with methotrexate or actinomycin D. High-risk and stage II to IV disease are treated with chemotherapy, radiotherapy, and surgery.

After treatment and hCG normalization, quantitative hCG levels should be evaluated monthly for a year with two physical exams. Due to the modest but present risk of recurrent choriocarcinoma, a first-trimester pelvic ultrasound should be conducted to confirm uterine placement. The placenta should be sent for histologic investigation of recurrence.

To prevent the spread of choriocarcinoma, women who have experienced a molar pregnancy—whether whole or partial—should be informed of the potential dangers. These patients need close observation until their hCG levels normalize. If a woman has given birth and is still bleeding after a certain amount of time, she should be encouraged to return to the hospital, especially if she is considered to be at high risk.

References

Bishop BN, Edemekong PF. Choriocarcinoma. [Updated 2022 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK535434/

WebMD (2022). What Is Choriocarcinoma?. Retrieved November 16, 2022, from https://www.webmd.com/cancer/what-is-choriocarcinoma

Last Updated: September 27, 2023