Abstract
PURPOSE: This prospective Brazilian single-arm trial was conducted to determine response to chemotherapy and survival after response-based radiotherapy in children with intracranial germinomas, in the setting of a multi-institutional study in a middle-income country (MIC) with significant disparity of subspecialty care. PATIENTS AND METHODS: Since 2013, 58 patients with histologic and/or serum and CSF tumor marker evaluations of primary intracranial germ cell tumors were diagnosed; 43 were germinoma with HCGβ levels ≤200 mIU/mL and five between 100 and 200 mIU/mL. The treatment plan consisted of four cycles of carboplatin and etoposide followed by 18 Gy whole-ventricular field irradiation (WVFI) and primary site(s) boost up to 30 Gy; 24 Gy craniospinal was prescribed for disseminated disease. RESULTS: Mean age 13.2 years (range, 4.7-25.5 years); 29 were males. Diagnosis was made by tumor markers (n = 6), surgery (n = 25), or both (n = 10). Two bifocal cases with negative tumor markers were treated as germinoma. Primary tumor location was pineal (n = 18), suprasellar (n = 14), bifocal (n = 10), and basal ganglia/thalamus (n = 1). Fourteen had ventricular/spinal spread documented by imaging studies. Second-look surgery occurred in three patients after chemotherapy. Thirty-five patients achieved complete responses after chemotherapy, and eight showed residual teratoma/scar. Toxicity was mostly grade 3/4 neutropenia/thrombocytopenia during chemotherapy. At a median follow-up of 44.5 months, overall and event-free survivals were 100%. CONCLUSION: The treatment is tolerable, and WVFI dose reduction to 18 Gy preserves efficacy; we have demonstrated the feasibility of successfully conducting a prospective multicenter trial in a large MIC despite resource disparity.