What Is a Trophoblastic Tumor?

A trophoblastic tumor is a rare kind of malignancy that arises from fertilized eggs in the uterus. It may behave like a regular pregnancy at first, as it will produce hormones associated with pregnancy, and growth will be visible in the uterus on ultrasound. Some forms are metastatic and may spread beyond the uterus, while others will remain isolated to the uterus. Management of the tumor requires removing the growth and treating the patient to prevent a recurrence.

In these types of tumors, a sperm successfully fertilizes an egg, but something goes wrong with the pregnancy. A hydatidiform mole is one form of trophoblastic tumor, where the rapidly dividing cells start to produce a series of cysts that look like a clump of grapes, instead of a fetus. Patients can also develop choriocarcinoma, which may spread beyond the uterus if not caught. Very rarely, the growth takes place at the placental site, and is known as placental-site trophoblastic disease.

Patients with trophoblastic tumors will experience symptoms like pain, swelling, and vaginal bleeding. A doctor can diagnose the cancer with the use of medical imaging, blood tests, and a patient history. The first line in treatment is removal of the growth before it can spread. The doctor can perform several different procedures to get the cancer out, including a hysterectomy, where she will remove the uterus entirely. This is an option in patients who do not plan to become pregnant again.

Chemotherapy and radiation may also be part of trophoblastic tumor treatment. These will destroy any remaining cancerous cells and reduce the risk of a recurrence. The patient will need to take precautions to avoid pregnancy during treatment to protect her health and that of the fetus, and may need to remain on birth control for several weeks or months after treatment to reduce the chances of birth defects in a future pregnancy. A doctor can discuss the various treatment options and future fertility with the patient to determine the best choice.

The causes for trophoblastic tumor formation are not understood. There are no obvious risk factors, and a patient may be very healthy. Any woman of reproductive age is potentially at risk for this type of malignancy, and it is important to receive a medical evaluation early during any suspected pregnancy so a doctor can confirm, screen for disease, and monitor the patient. Early diagnosis of a trophoblastic tumor can make a significant difference when the growth is one that may spread to other organs, as it can invade the uterine wall and work its way into the pelvis and abdominal cavity.