gynecology and obstetrics
Gestational Trophoblastic Disease
Diagnosis of Gestational Trophoblastic Disease
Serum beta subunit ofhuman chorionic gonadotropin(beta-hCG) Pelvic ultrasonography Pathology evaluation of evacuated uterine contents or endometrial biopsy Gestational trophoblastic disease is suspected in women with a positive pregnancy test and any of the following: Unexpectedly high levels of beta-hCG detected during pregnancy testing (except for placental site trophoblastic tumor and epithelioid trophoblastic tumor, which result in low beta-hCG levels) Uterine size much larger than expected for dates Symptoms or signs of preeclampsia in 1st or 2nd trimester Vaginal passage of grapelike tissue Suggestive findings (eg, mass containing multiple cysts, absence of a fetus and amniotic fluid) seen during ultrasonography done to evaluate pregnancy Unexplained metastases in women of child-bearing age with an unknown primary tumor Postmolar gestational trophoblastic neoplasia is most frequently diagnosed based on hCG levels and should be excluded if abnormal uterine bleeding occurs after any pregnancy. Do ultrasonography during early pregnancy if uterine size is much larger than expected for dates, if beta-hCG levels are unexpectedly high, or if women have symptoms or signs of preeclampsia. If gestational trophoblastic disease is suspected, testing includes measurement of serum beta-hCG and, if not previously done, pelvic ultrasonography. Findings (eg, very high beta-hCG levels, classic ultrasonographic findings) may suggest the diagnosis, but the diagnosis must be histologically confirmed through pathology evaluation of evacuated uterine contents or endometrial biopsy. Typically, beta-hCG levels are high in patients with invasive mole or choriocarcinoma and low in those with placental site trophoblastic tumor or epithelioid trophoblastic tumor. Invasive mole and choriocarcinoma are suspected if biopsy findings suggest invasive disease or if beta-hCG levels remain higher than expected after treatment for hydatidiform mole (see below). Thyroid function tests are done if the beta-hCG level is > 100,000 mIU/mL (> 100,000 IU/L) to check for hyperthyroidism. When gestational trophoblastic neoplasia is diagnosed, clinicians should check for metastases. CT of the chest, abdomen, and pelvic area should be done. Pelvic ultrasonography or MRI may be helpful if better visualization of the uterine tumor is needed or if there are ovarian theca lutein cysts. Metastases to other sites usually occur only after metastases to the lungs are established. Before gestational trophoblastic disease is treated, it is assigned the following: A stage based on the 2000 International Federation of Gynecology and Obstetrics (FIGO) staging system (see table) A risk score based on the modified World Health Organization [WHO] prognostic scoring system (see table) Both systems correlate with clinical outcomes and identify patients at risk of treatment failure. 