Accurate short tandem repeat analysis for confirmation of rare gestational adrenal choriocarcinoma: a case report

Rare adrenal choriocarcinoma should be identified as gestational or nongestational choriocarcinoma because of their different treatment and prognosis. A 29-year-old parous women underwent curettage and right-oviduct resection successively due to irregular vaginal bleeding and positive human chorionic gonadotropin (HCG). Postoperative pathological examinations revealed no intrauterine and extrauterine pregnancy. After that, HCG continued to rise. A 7.6×10.3×11.0 cm mass was present in the left adrenal gland with an uneven inner density and a complete capsule by computed tomography (CT). A biopsy was performed on the mass, which showed us choriocarcinoma. Seven cycles of chemotherapy made her complete response and under supervision. Recurrent diagnosis was done after 3 months. The tumor specimen, the patient's blood, and her husband's blood were drawn for short tandem repeat (STR) analysis using polymerase chain reaction amplification kit. The genotype of the tumor cells was both maternal and patrilineal, which led to the diagnosis of adrenal gestational choriocarcinoma. The patient was scheduled for adrenalectomy and various chemotherapeutic interventions before and after operation. She achieved complete response and was being followed up again. STR analysis first aids in precise classification of this rare adrenal choriocarcinoma. We encourage using the method to analyze choriocarcinoma outside reproductive organs.