Is there a role for carboplatin in the treatment of malignant germ cell tumors? A systematic review of adult and pediatric trials.

While cisplatin is considered superior to carboplatin for the treatment of malignant germ cell tumors (MGCTs) in adults, pediatric oncology collaborative groups still remain concerned about the late effects of cisplatin in children. We performed a literature search to identify randomized controlled trials (RCTs) that used carboplatin for MGCTs in adults. Since no RCTs were available in children, we identified cohort studies of pediatric MGCTs treated with carboplatin. We compared the adult and pediatric studies in terms of characteristics, doses of chemotherapy, and outcomes. Of 2,131 publications retrieved, five RCTs in adults (1,340 patients) and four cohort studies in children (219 patients) met criteria for inclusion. All adult RCTs evaluated carboplatin versus cisplatin regimens in men with good-prognosis metastatic MGCTs. Carboplatin regimens had a higher risk of events (RR 2.51, P < 0.001) and of deaths (RR 2.21, P < 0.001) than cisplatin regimens. Across all five RCTs, 497/654 (76%) of adults who received carboplatin remained event-free. Compared to the adult trials, three pediatric studies used carboplatin at a higher dose, frequency, and number of cycles. Across these three studies, 158/179 (88%) of children remained event-free. Cisplatin is superior to carboplatin at the studied doses for the treatment of adult metastatic MGCTs. However, we observe that carboplatin is associated with good outcomes for children with MGCT when used at the higher doses. We hypothesize that a risk-adapted approach utilizing both platinum agents may achieve the optimal balance between cure and late effects.