What is the diagnosis?
Hydatidiform mole. This is the most common type of gestational trophoblastic disease (GTD).
How does this lesion arise?
Complete hydatidiform moles occur with uniparental disomy with loss of the maternal chromosomes followed by duplication of the paternal haploid genome. About 5% of complete moles result from dispermic fertilization of an empty egg. Most moles have a 46XX karyotype. There are several other forms of GTD: partial mole, invasive mole, placental site trophoblastic tumor, and choriocarcinoma.
What will you do to follow the patient?
Use beta-HCG levels. The levels should continue to decrease within 10 days following evacuation of the mole, as happens in a little over 80% of cases. Continued increased HCG levels suggest the possibility of invasive mole (16%) or choriocarcinoma (2.5%).
If HCG levels do not decrease, then early treatment of persistent trophoblastic disease by chemotherapy has a near 100% cure and prevents progression to more advanced trophoblastic malignancy such as choriocarcinoma. Methotrexate and/or leukovorin have been employed. Patient with high-risk tumors may receive chemotherapy with MAC (methotrexate, antinomycin-D, cyclophosphamide).
