Choriocarcinoma syndrome is an uncommon, potentially fatal complication of germ cell tumors (GCTs) in adults, but it is not well documented in children. Pediatric central nervous system (CNS) GCTs comprise a rare group of malignancies not usually associated with extra-CNS metastatic disease. Here, we report the case of a pediatric patient with a suprasellar mixed GCT and pulmonary metastases who presented with intratumoral hemorrhage and stroke. Choriocarcinoma syndrome developed soon after initiating chemotherapy. The primary tumor and pulmonary metastases were successfully treated using a multidisciplinary approach, including neurovascular intervention, chemotherapy, and craniospinal irradiation.

Nongestational ovarian choriocarcinoma (NGOC) accounts for <1% of ovarian germ cell tumors and may develop into the rare and fatal complication of choriocarcinoma syndrome. We reported a case of a 12-year-old girl with NGOC that metastasized to the lungs, retroperitoneal lymph nodes and brain. On day 2 of chemotherapy with actinomycin D and etoposide, choriocarcinoma syndrome developed due to a massive pulmonary hemorrhage, presenting as acute respiratory distress syndrome. The patient received mechanical ventilation and multimodal support and completed two cycles of an actinomycin D and etoposide regimen with intubation. After the patient\'s acute respiratory distress syndrome was under control, she received 9 cycles of more intensive chemotherapy regimens and achieved complete remission. An exploratory laparotomy with salpingo-oophorectomy confirmed ovarian choriocarcinoma. The patient remained disease-free at a 3-month follow-up visit. In conclusion, appropriate management consisting of multimodal support and timely, sequential and intensive chemotherapy is effective for NGOC complicated with choriocarcinoma syndrome. Stating with mild regimens would probably reduce the risk of choriocarcinoma syndrome, or at least lessen its severity. To our knowledge, we presented the first report of NGOC-related choriocarcinoma syndrome.