Clinical experience with EMACO chemotherapy in male choriocarcinoma: A single-center study.

640 Background: Choriocarcinoma is an aggressive subtype of germ cell tumor that frequently metastasizes and progresses rapidly. In gestational trophoblastic tumors in females, the etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine (EMACO) regimen is commonly used, but there are limited reports of its use in male choriocarcinoma. The purpose of this study was to retrospectively describe the clinical outcomes of the EMACO regimen in male patients with pathologically confirmed or clinically highly suspected choriocarcinoma at a single institution. Methods: We conducted a retrospective review of the medical records of male patients who received at least one cycle of EMACO chemotherapy between February 2013 and September 2023 at a tertiary hospital in Korea. We analyzed their baseline characteristics, tumor response, survival outcomes, and adverse events. Resection of residual tumors following EMACO chemotherapy was also considered part of the treatment process. The evaluation of tumor response was based on radiological examinations and changes in tumor markers. Results: In total, 15 patients were included in the study with a median age of 26 years. During diagnosis, 7 patients were found to have pure choriocarcinoma cell components on pathological examination, but all patients had elevated beta-hCG levels (median 177,000 mIU/mL, range 312–11,478,883 mIU/mL). At the time of EMACO administration, lung metastasis was the most frequent, observed in 12 patients, followed by brain metastasis in 7 patients. Seven patients received EMACO chemotherapy as 1 st or 2 nd -line treatment. The median number of chemotherapy cycles was 6. Tumor marker reduction or a decrease in tumor size was observed in 11 patients. Residual tumor resection was performed immediately after EMACO treatment in 7 patients, and no recurrence was observed in 6 patients during the follow-up period. Regarding Grade 3-4 toxicity, anemia was observed in 10 patients, thrombocytopenia in 6 patients, neutropenia in all patients, and elevated alanine aminotransferase levels in 6 patients. The median OS was not reached, with a median follow-up time of 24 months and a median PFS of 10.2 months. Conclusions: EMACO chemotherapy is an effective regimen for male germ cell tumors with pathologically confirmed choriocarcinoma components or markedly elevated hCG levels, and it may offer a curative treatment option when combined with resection of residual tumors.