Acute toxicity profile of craniospinal irradiation with intensity-modulated radiation therapy in children with medulloblastoma: A prospective analysis

Background: To report on the acute toxicity in children with medulloblastoma undergoing intensity-modulated radiation therapy (IMRT) with daily intrafractionally modulated junctions. Methods: Newly diagnosed patients, aged 3-21, with standard-risk (SR) or high-risk (HR) medulloblastoma were eligible. A dose of 23.4 or 36.0Gy in daily fractions of 1.8Gy was prescribed to the craniospinal axis, followed by a boost to the primary tumor bed (54 or 55.8Gy) and metastases (39.6-55.8Gy), when indicated. Weekly, an intravenous bolus of vincristine was combined for patients with SR medulloblastoma and patients participating in the COG-ACNS-0332 study. Common toxicity criteria (CTC, version 2.0) focusing on skin, alopecia, voice changes, conjunctivitis, anorexia, dysphagia, gastro-intestinal symptoms, headache, fatigue and hematological changes were scored weekly during radiotherapy. Results: From 2010 to 2014, data from 15 consecutive patients (SR, n=7; HR, n=8) were collected. Within 72h from onset of treatment, vomiting (66%) and headache (46%) occurred. During week 3 of treatment, a peak incidence in constipation (33%) and abdominal pain/cramping (40%) was observed, but only in the subgroup of patients (n=9) receiving vincristine (constipation: 56 vs 0%, P=.04; pain/cramping: 67 vs 0%, P=.03). At week 6, 73% of the patients developed faint erythema of the cranial skin with dry desquamation (40%) or moist desquamation confined to the skin folds of the auricle (33%). No reaction of the skin overlying the spinal target volume was observed. Conclusions: Headache at onset and gastro-intestinal toxicity, especially in patients receiving weekly vincristine, were the major complaints of patients with medulloblastoma undergoing craniospinal irradiation with IMRT.