Choriocarcinoma Cancer - Symptoms, Pathophysiology, Diagnosis and Treatment
Choriocarcinoma is a type of gestational trophoblastic cancer of the placenta . This form of cancer occurs only during pregnancy and most of the times it is curable, provided it is diagnosed in early stages. However, in certain cases it can occur even after an abortion, ectopic pregnancy or genital tumor .
It is a quick growing form of cancer that takes shape in the women’s uterus. The cancer begins by abnormal division of cells in the tissue that would have normally developed as placenta in pregnant women . The cancer also spreads to the lungs and brain .
Statistics have revealed that choriocarcinoma occurs in 1 out of every 40,000 pregnancies .
Location / site of development of choriocarcinoma
The primary site of development of choriocarcinoma is the placenta and hence it is also sometimes referred to as placental choriocarcinoma. There have been pieces of evidence reporting that choriocarcinoma can also develop in other organs (other than the placenta) such as testicles, cervix and ovaries.
Site of development of choriocarcinoma other than the reproductive organs is rare but cannot be ruled out. These sites include :
- Brain known as intracranial choriocarcinoma
- Lungs known as pulmonary choriocarcinoma
- Small intestine
- Pancreas and
- Pulmonary arteries
Symptoms of choriocarcinoma
Continued abnormal vaginal bleeding (different from menstrual bleeding) is the most common sign of choriocarcinoma. This symptom is more common in women who have past history of hydatidiform mole, abortion or pregnancy . Symptoms of choriocarcinoma often depend on the type of the body part affected. The other signs and symptoms of choriocarcinoma include [3, 8]:
- Ovarian cysts
- Swelling of the uterus
- Irregular vaginal bleeding
- Nausea and vomiting
- Abdominal swelling
- Increased HCG levels that do not return to normal even after pregnancy
- Abnormal discharge from the nipple
- The size of the uterus does not change even after delivery
- Lump in the vagina
Choriocarcinoma during pregnancy
Women aged 40 and above are at a higher risk of developing choriocarcinoma. Moreover, past history of molar pregnancy, ectopic pregnancy, abortions and miscarriages increases the risk of developing choriocarcinoma .
The most important factor for development of choriocarcinoma in pregnant women is the malignant transformation of trophoblast . During normal pregnancy, the trophoblastic cells together form the placenta – the organ that supplies nutrition to the growing baby. However, in cases, when the pregnant women have had a past history of hydatidiform mole, the trophoblastic cells undergo malignant transformation, to form grape like eater filled masses instead of the placenta. The mole may have been removed, but its remnants may still be there in the uterus to cause malignancy.
Causes of choriocarcinoma
Choriocarcinoma is a curable form of cancer when detected in early stages. When you are affected with this form of cancer, it affects the proper development of fetus . There are several causative factors of choriocarcinoma. The important ones are listed below:
- Hydatidiform mole – Research has revealed that about 50% women who suffered from hydatidiform mole in the past developed choriocarcinoma later during their life .
- Past history of ectopic pregnancy or genital tumor may also cause development of choriocarcinoma .
- Choriocarcinoma can also stem from conditions such as miscarriage .
- Spontaneous abortion is yet another major causative factor for development of choriocarcinoma. Research has revealed that about 20% cases of choriocarcinoma in women have been with spontaneous abortions .
Diagnosis of Choriocarcinoma
Women with choriocarcinoma will give a positive result fro pregnancy test even when they are not pregnant. The pregnant hormone HCG levels will be elevated. In addition, the following tests will be done to diagnose the disease .
Blood tests will be done to at the primary level to determine
- Quantitative serum HCG
- Complete blood count
- Kidney functioning
- Liver functioning
Imaging tests that need to be done in addition to the blood tests include:
- CT scan
In addition to these tests, physical examination of the pelvic will show presence of tumor. Biopsy of the tumor for testing its nature is never done before treatment as there are chances of heavy bleeding.
Treatment of choriocarcinoma depends on several components:
- Nature and spread of the cancer to other body parts
- Age of the patients
Gestational choriocarcinoma that usually arises from hydatidiform mole has been found to be sensitive to chemotherapy. The cure rate for gestational choriocarcinoma using chemotherapy is 90 – 95% .
Chemotherapy with surgery is the main type of treatment for choriocarcinoma. There may be mild to moderate bleeding for few days post surgery. Surgery is followed by chemotherapy for complete removal of the cancerous tumors. Chemotherapy is administered through drugs via the oral route or injected directly into the blood stream . Methotrexate is the drug of choice for treating choriocarcinoma.
The need of hysterectomy is rare in such cases as the disease gets treated with chemotherapy. However, in instances when there is heavy bleeding, severe infection and the age of the patient is greater than 40 years and for whom sterilization is not an issue then this procedure is adopted .
Radiation therapy is required only when the cancer has spread to the brain.
If the cancer has been detected in early stages and timely treatment initiated then there are pretty less chances of the cancer returning back. However, research has proved that in certain cases, the cancer comes back within few months to 3 years of receiving complete treatment. Initiation of timely treatment also prevents the spread of the cancer to other parts of the body. In addition, women can also conceive and deliver a healthy baby with full treatment.
The cancer gets difficult to treat under the following conditions :
- The cancer has spread to liver and brain
- Cancer comes back even after receiving chemotherapy
- Choriocarcinoma developed after the woman delivered a healthy child
- Levels of HCG hormone is higher than 40,000mIU/mL at the time of treatment
- The woman experienced symptoms similar to those of pregnancy for at least 4 months before initiation of treatment
Complications of choriocarcinoma
Complications of choriocarcinoma are based on the spread of the cancer to other parts of the body. Women may develop pneumonia when the cancer has affected the lungs .
Patients may also fall prey to hemorrhage due to high vascularity of the actual tumor or other tumors that has spread to the other parts of the body .
The other secondary complications of choriocarcinoma include hyperthyroidism, uterine enlargement and intramenstrual PV bleed .
- http://www.whattoexpect.com/pregnancy/pregnancy health/complications/choriocarcinoma.aspx
- http://health.nytimes.com/health/guides/disease/gestational-trophoblastic-disease/ http://www.ncbi.nlm.nih.gov/pubmed/20736774