Gestational Trophoblastic Disease

What is gestational trophoblastic disease?

Gestational trophoblastic disease (GTD) are tumors that start in your uterus (womb) related to pregnancy. The tumors start off as cells called trophoblasts, which typically develop into the placenta of pregnancy. The placenta is an organ that connects the fetus to your uterus (and you), providing all the oxygen and nutrients it needs to grow.

With gestational trophoblastic disease, the trophoblasts (placenta-like cells) grow abnormally, instead of into a healthy placenta.

Most cases of GTD occur early in pregnancy, soon after sperm fertilizes an egg, and are called molar pregnancies. Despite being called pregnancies, these cells don’t develop into a fetus that will develop into a baby. They’re typically noncancerous (benign), although some can be cancerous and spread to nearby tissues or organs. Most importantly, GTD is treatable and curable, and most people can go on to have healthy pregnancies in the future.

When does gestational trophoblastic disease happen?

While most common during the beginning of a pregnancy, GTD can also occur:

• After a miscarriage or abortion.
• After a tubal pregnancy (the fertilized egg implants in your fallopian tube and not in your uterus).
• After a normal pregnancy.

What are the types of gestational trophoblastic disease?

There are several types of gestational trophoblastic disease. Symptoms vary depending on the type.

Hydatidiform mole or molar pregnancy

Hydatidiform moles are the most common form of GTD. Commonly called a molar pregnancy, it happens when grape-like cysts grow in your uterus instead of the placenta or fetus. You may feel pregnant and get a positive pregnancy test, but find no fetus growing during a prenatal ultrasound. The positive pregnancy test is due to the pregnancy hormone made inside the placenta. Hydatidiform moles also come in two forms: complete or partial hydatidiform moles. Most molar pregnancies aren’t cancerous.

Common symptoms of a molar pregnancy include abnormal vaginal bleeding early in a suspected pregnancy, which can be red or watery brown, and sometimes include abdominal pain.

Persistent/invasive molar pregnancy

Considered a result of a molar pregnancy, an invasive mole may grow into your uterine muscle. Unlike other types of molar pregnancy, invasive moles are typically cancerous. The cancer cells usually stay in the muscles of your uterus but may spread to other body parts or tissue without treatment.

Choriocarcinoma

Choriocarcinoma is a form of cancerous GTD that grows and spreads quickly. It may spread from your uterine muscles to your vagina, lung and other organs, like your kidneys, liver or brain. While still very rare, it’s more common in people who’ve already had a molar pregnancy.

Some people don’t have any symptoms, but in those who do, the most common is abnormal vaginal bleeding after pregnancy, miscarriage or molar pregnancy. Some people have abdominal pain or blood in their pee or poop.

Placental site trophoblastic tumor (PSTT)

A placental-site trophoblastic tumor (PSTT) is an extremely rare type of GTD that forms where the placenta attaches to your uterus. A PSTT grows very slowly, and symptoms may appear years after pregnancy. PSTTs may spread into the muscles of your uterus and your blood vessels, lungs, pelvis and lymph nodes and require aggressive treatment.

Epithelioid trophoblastic tumors (ETT)

This is also a very rare type of GTD that is cancerous. As with PSTT, it can spread to your lungs. ETT may also develop years after pregnancy.

How common is this condition?

GTD occurs in about 1 in every 1,000 pregnancies in the United States. Most cases of GTD are hydatidiform moles (molar pregnancy). More serious cases of GTD like choriocarcinoma occur in fewer than 1 in 20,000 pregnancies.

Is gestational trophoblastic disease fatal?

Most GTD cases are treated and cured, especially when diagnosed early. But cases of advanced GTD can be fatal.

What are the symptoms of gestational trophoblastic disease?

Some people have no symptoms of GTD. Others have symptoms that mimic pregnancy or other conditions/diseases. Contact your healthcare provider if you have any of these symptoms:

• Irregular vaginal bleeding or bleeding that’s unrelated to your period.
• A uterus that measures large for your expected pregnancy.
• Pain in your abdominal area or pelvic area.
• Nausea or throwing up earlier than expected during pregnancy.
• High blood pressure or swollen hands and feet early in pregnancy.
• Prolonged vaginal bleeding after childbirth or miscarriage.

Gestational trophoblastic disease may cause an overactive thyroid. Signs of an overactive thyroid include:

• Fast heartbeat.
• Shakiness.
• Weight loss.
• Sweating.

What causes molar pregnancies or hydatidiform moles?

In a normal pregnancy, an egg is fertilized by sperm and contains all the information it needs to make an embryo and placenta. This initial collection of cells is called a blastocyst. The embryo eventually becomes a fetus, while layers of a trophoblast cell become part of the placenta and help connect the blastocyst to your uterine wall.

In molar pregnancies, given that fertilization didn’t happen correctly, the embryo doesn’t develop correctly and the trophoblastic cells grow into tumors instead of a healthy placenta.

How is gestational trophoblastic disease diagnosed?

Your healthcare provider diagnoses GTD after a complete review of your medical history, a physical exam and other tests that look at the inside of your uterus. Diagnosing GTD may include:

• Pelvic exam: Your provider inserts gloved fingers into your vagina to check for signs of disease such as lumps and masses, and/or to determine the size of your uterus.
• Ultrasound: A procedure in which sound waves create a picture of your internal organs. If your provider suspects GTD, a transvaginal ultrasound will take images of your pelvis and uterus.
• Blood tests: Blood tests measure the amount of certain substances in your body to help diagnose GTD. For example, a pregnant person with GTD may have higher human chorionic gonadotropin (hCG) hormone levels than a pregnant person without GTD. If cancer has spread to other tissues or organs, your body may release higher or lower amounts of certain substances to indicate disease.

Once GTD is diagnosed, your provider may order additional tests to see if the cancer cells have spread to other parts of your body. Finding out how far or how much cancer has spread is called staging. The results tell providers what stage of cancer you may have.

Stages of cancer are written in Roman numerals as I, II, III and IV. The higher the number, the more cancer has spread.

The tests used to determine stages of GTD could include:

• Computed tomography (CT scan): Uses a series of X-rays and a computer to produce a 3D image of tissues and bones.
• Magnetic resonance imaging (MRI): A magnet and radio waves make detailed pictures of your body. Your provider may inject gadolinium into your veins because this substance makes cancer cells appear brighter in the picture.
• Chest X-ray: An X-ray uses a focused radiation beam to look at your lungs and other organs and bones inside your chest.

How is gestational trophoblastic disease treated?

Gestational trophoblastic disease treatment varies depending on several factors, such as:

• GTD type, size and location.
• If the tumor has spread or its stage.
• If the tumor occurred during pregnancy or after a miscarriage or pregnancy.
• Your overall health.
• Your medical history and previous treatment for GTD.
• Your plans for children.

Your healthcare provider will determine what course of treatment makes the most sense based on your condition. Specific treatment methods for GTD include:

• Surgery: Surgery to remove irregular tissues and cells from your uterus. The most common surgery used for GTD is a dilation and curettage (D&C).
• Chemotherapy: Chemotherapy (or chemo) uses drugs to destroy cancer cells.
• Radiation: Radiation therapy uses strong energy beams to kill cancer cells and shrink tumors.
• Hysterectomy: A hysterectomy is the surgical removal of your uterus. Other organs such as your fallopian tubes or ovaries may also be removed.

You and your healthcare provider should discuss possible treatments and risks and side effects of treatment.

Can gestational trophoblastic disease come back?

Yes, gestational trophoblastic disease can come back. You’re at a slightly higher risk of recurrence depending on the type you originally had and your response to treatment.

Can I prevent gestational trophoblastic disease?

There isn’t a way to prevent gestational trophoblastic disease.

Risk factors for GTD

Gestational trophoblastic disease is rare, but certain factors beyond your control may increase your risk. These factors include:

• Your age. People older than 35 or younger than 20 may be at higher risk for GTD.
• Having prior molar pregnancies.
• Strong family history of molar pregnancies.

Can you have a baby after gestational trophoblastic disease?

Yes, most people with a history of GTD can expect to have normal pregnancies afterward. Your provider may recommend extra testing during any subsequent pregnancies depending on your history.