Gestational trophoblastic disease (GTD) is a spectrum of rare tumors that arise from abnormal placental trophoblastic tissue, including benign disease such as complete and partial hydatidiform moles, as well as malignant tumors such as invasive mole, choriocarcinoma, placental site trophoblastic tumor, and epithelioid trophoblastic tumor.
Risk factors for GTD include geography, socioeconomic status, dietary factors, maternal age, and previous GTD history.
GTD is historically diagnosed based on pathology, but due to earlier detection because of routine early ultrasonography, diagnosis of a molar pregnancy based on histology alone may be difficult, and cytogenetic techniques can assist in diagnosis.
The diagnosis of malignant disease, or gestational trophoblastic neoplasia, is based on increase or plateau of human chorionic gonadotropin (hCG) levels, tissue diagnosis of choriocarcinoma, or evidence of metastatic disease.
After the diagnosis of malignant disease, it is imperative that patients be staged and scored using International Federation of Gynecology and Obstetrics 2000 staging incorporating the modified World Health Organization scoring system to determine whether single- or multiagent therapy is appropriate.
Throughout the course of treatment, patients should be monitored with every 1- to 2-week serum hCG levels to determine response.
Gestational trophoblastic disease (GTD) is a spectrum of rare tumors arising from abnormal placental trophoblastic tissue. It ranges from benign disease, including complete and partial hydatidiform moles, to malignant tumors such as invasive mole, choriocarcinoma, placental site trophoblastic tumor (PSTT), and epithelioid trophoblastic tumor (ETT). The malignant disease is otherwise known at gestational trophoblastic neoplasia (GTN) or gestational trophoblastic tumor.
Our knowledge of hydatidiform moles dates back to 400 B.C., when Hippocrates was the first to describe them as “dropsy of the uterus.”1 By the mid-20th century, similar to other malignancies, survival rates were dismal. During this time, the mortality rate for invasive moles neared 15% because of hemorrhage, sepsis, embolic disease, or complications from surgery.2 Additionally, choriocarcinoma had a mortality rate close to 100% when metastases were present and approached 60% even when hysterectomy was performed for nonmetastatic disease. Even benign hydatidiform moles had poor prognoses because of life-threatening hemorrhage and other medical complications. However, because of the identification of a specific and accurate biomarker used for follow-up as well as the development of an effective chemotherapy treatment, current management of patients with GTD yields cure rates approaching 100%.
GTD is rare accounting for fewer than 1% of all gynecologic tumors. However, the exact rate of prevalence is difficult to determine because of the rarity of the disease, inconsistent use of definitions, and a lack of centralized databases.3 Despite this, various studies have identified a number of risk factors associated with GTD. These include but are not limited to geography, socioeconomic status, dietary factors, maternal age, and previous GTD history.
GTD is variable throughout different regions of the world. In the United States, GTD occurs in roughly 1 in ...