What's New in Gestational Trophoblastic Disease Research and Treatment?
Important research into gestational trophoblastic (jeh-STAY-shuh-nul troh-fuh-BLAS-tik) disease (GTD) is being done right now in many university hospitals, medical centers, and other institutions around the country. Each year, scientists find out more about what causes the disease and how to improve treatment.
Causes of GTD
Researchers are studying cells of GTD to learn more about how these tumors develop. Discoveries about chromosome abnormalities of complete and partial moles have helped explain the causes of these types of GTD. These discoveries have led to developing lab tests that can help identify these 2 types of moles (partial vs. complete) when routine microscopic analysis does not yield a clear answer.
Researchers often collect data on how often various forms of cancer occur in different parts of the world and whether these diseases are becoming more or less common. This often provides clues about risk factors and ideas for prevention. Earlier studies suggested that choriocarcinoma (KOR-ee-oh-KAR-sih-NOH-muh) and GTDs were 5 to 10 times more common in Asia than in Europe and North America. More recent information indicates that the difference is actually no greater than double and may be even less, and that the original estimates were likely biased by differences in the way births are recorded in different countries.
Staging and prognosis
Newer and more sensitive tests are now able to more accurately determine blood human chorionic gonadotropin (HCG) levels than in the past. Scientists have developed a blood test for a form of HCG known as hyperglycosylated HCG. Early studies suggest that this blood test may help separate patients with active GTD who need treatment from those who have elevated HCG levels but don't truly have GTD, and therefore may not require therapy. More studies are needed to confirm this.
Improvements in the staging systems and prognostic classification systems are making it easier for doctors to recognize which patients will benefit from which treatments.
In recent years, a number of studies have shown the value of using combination chemotherapy (chemo) for high-risk metastatic GTD, such as the EMA-CO and EMA-EP regimens (these were discussed in the section about chemotherapy). The excellent results with these regimens have made them treatments of choice in many institutions.
Newer chemo drugs including pemetrexed, paclitaxel, and gemcitabine have been studied for use in this disease, as are several new combinations of drugs. Some of these are already in use in women whose GTD doesn't respond to other treatments.
For tumors that are resistant to standard chemo doses, doctors are studying the use of high-dose chemo followed by a stem cell transplant to restore the patient's bone marrow. Some very early results have been promising, but more research is needed.
Researchers are also studying ways to give the usual chemo drugs with new schedules that might be more effective, cause less severe side effects, and/or be more convenient for patients.
Last Medical Review: February 6, 2014 Last Revised: February 9, 2016