Gestational trophoblastic disease (GTD) encompasses a spectrum of disorders related to unregulated growth arising from trophoblastic cells. During normal pregnancy, trophoblastic cells invade the endometrium, promote angiogenesis, and thus help create a rich uterine vasculature that ultimately becomes the placenta. However, in rare circumstances, these cells can become hyperplastic and invasive, presenting as a group of diseases ranging from molar pregnancies to metastatic choriocarcinoma. Anesthetic management is centered on treating the specific medical complications associated with GTD while also preparing for significant blood loss and cardiopulmonary instability.
GTDs are a group of diseases with a myriad of clinical features depending on the pathogenesis. The World Health Organization classifies GTD into two primary categories and six subgroups according to histopathological, cytogenetic, and clinical features (Table 163-1).
TABLE 163-1Modified World Health Organization Classification of Gestational Trophoblastic Disease ||Download (.pdf) TABLE 163-1 Modified World Health Organization Classification of Gestational Trophoblastic Disease
Hydatidiform moles are further categorized as either complete, partial, or invasive moles (Table 163-2). In general, hydatidiform moles are characterized by trophoblastic proliferation and intracellular edema or hydropic swelling that manifest as cystic swelling of the chorionic villi. Classically, hydatidiform moles demonstrate persistently elevated human chorionic gonadotropin (HCG) levels that are produced by syncytiotrophoblasts as they invade the endometrial stroma.
TABLE 163-2Features of Complete and Partial Hydatidiform Moles ||Download (.pdf) TABLE 163-2 Features of Complete and Partial Hydatidiform Moles
|Feature ||Complete Mole ||Partial Mole |
|Karyotype ||46XX or 46XY ||69XXY, 69XXX, 69XYY |
Variable, may be marked
Focal and minimal
Postmolar malignant sequelae
|Molar gestation 15% ||Missed abortion 4%–6% |
Complete hydatidiform moles are trophoblastic lesions characterized by diffuse hydropic swelling. The trophoblasts are derived from the three main cell lines (cytotrophoblasts, syncytiotrophoblasts, and intermediate trophoblasts). Cytogenetically, complete moles are diploid and usually derived entirely from paternal chromosomes. The empty ovum is either fertilized by a single sperm that then duplicates its genetic material, or by two separate sperm. The resulting karyotype of the former is 46XX, while the latter can produce either 46XX or 46XY. Ninety percent of complete moles have the 46XX karyotype while 10% have the 46XY karyotype with the mitochondrial DNA being maternally derived.
Partial hydatidiform moles are trophoblastic lesions characterized by the presence of syncytiotrophoblasts and cytotrophoblasts cell lines. This results in more diffuse hydropic villi with focal areas of trophoblastic hyperplasia. Partial hydatidiform moles develop when a 23x ovum is fertilized by either two spermatozoa or a single sperm that duplicates its genetic material. This results in the formation of a triploid zygote with ...