Gestational trophoblastic tumor, a rare cancer in women, is a disease in which cancer (malignant) cells grow in the tissues that are formed following conception (the joining of sperm and egg). Gestational trophoblastic tumors start inside the uterus, the hollow, muscular, pear-shaped organ where a baby grows. This type of cancer occurs in women during the years when they are able to have children. There are two types of gestational trophoblastic tumors: hydatidiform mole and choriocarcinoma.
If a patient has a hydatidiform mole (also called a molar pregnancy), the sperm and egg cells have joined without the development of a baby in the uterus. Instead, the tissue that is formed resembles grape-like cysts. Hydatidiform mole does not spread outside of the uterus to other parts of the body.
If a patient has a choriocarcinoma, the tumor may have started from a hydatidiform mole or from tissue that remains in the uterus following an abortion or delivery of a baby. Choriocarcinoma can spread from the uterus to other parts of the body. A very rare type of gestational trophoblastic tumor starts in the uterus where the placenta was attached. This type of cancer is called placental-site trophoblastic disease.
Gestational trophoblastic tumor is not always easy to find. In its early stages, it may look like a normal pregnancy. A doctor should be seen if the there is vaginal bleeding (not menstrual bleeding) and if a woman is pregnant and the baby hasn’t moved at the expected time.
If there are symptoms, a doctor may use several tests to see if the patient has a gestational trophoblastic tumor. An internal (pelvic) examination is usually the first of these tests. The doctor will feel for any lumps or strange feeling in the shape or size of the uterus. The doctor may then do an ultrasound, a test that uses sound waves to find tumors. A blood test will also be done to look for high levels of a hormone called beta-HCG (beta human chorionic gonadotropin) which is present during normal pregnancy. If a woman is not pregnant and HCG is in the blood, it can be a sign of gestational trophoblastic tumor.