BACKGROUND: Persistently low-level "real" serum human chorionic gonadotropin (hCG) after treatment for gestational trophoblastic neoplasia (GTN) in patients desirous of preserving fertility is a diagnostic and management challenge. Among the possible explanations is the presence of false positive ("phantom") hCG or of trophoblasts in a myometrial sanctuary. CASE: An 18-year-old woman had persistent low-level hCG values in her serum after treatment for nonmetastatic GTN. Her only child had died, and she wanted to preserve her fertility potential. Phantom hCG was excluded. Positron emission tomography (PET) showed increased uptake in an area of the uterus in which magnetic resonance imaging had shown an ill-defined, ovoid lesion. Removal of the lesion with preservation of the uterus followed by 2 courses of multiagent chemotherapy (methotrexate, dactinomycin and cyclophosphamide) resuited in clinical remission. CONCLUSION: PET can prove useful in detecting persistent disease in a myometrial sanctuary in patients with resistant, nonmetastatic GTN. Conservative surgical excision with uterine preservation is possible and can be of value in achieving remission.
BACKGROUND: Persistently low-level "real" serum human chorionic gonadotropin (hCG) after treatment for gestational trophoblastic neoplasia (GTN) in patients desirous of preserving fertility is a diagnostic and management challenge. Among the possible explanations is the presence of false positive ("phantom") hCG or of trophoblasts in a myometrial sanctuary. CASE: An 18-year-old woman had persistent low-level hCG values in her serum after treatment for nonmetastatic GTN. Her only child had died, and she wanted to preserve her fertility potential. Phantom hCG was excluded. Positron emission tomography (PET) showed increased uptake in an area of the uterus in which magnetic resonance imaging had shown an ill-defined, ovoid lesion. Removal of the lesion with preservation of the uterus followed by 2 courses of multiagent chemotherapy (methotrexate, dactinomycin and cyclophosphamide) resuited in clinical remission. CONCLUSION: PET can prove useful in detecting persistent disease in a myometrial sanctuary in patients with resistant, nonmetastatic GTN. Conservative surgical excision with uterine preservation is possible and can be of value in achieving remission.