Medulloblastoma: long-term follow-up of patients treated with electron irradiation of the spinal field.

Thirty-two patients with posterior fossa medulloblastoma underwent treatment with electron irradiation to the spinal field. The 5- and 10-year actuarial survival rates were 57% and 50%, respectively. Late complications observed in the 15 patients followed up for more than 5 years were short stature (six patients), decreased sitting-standing height ratio (four patients), scoliosis (two patients), poor school performance (seven patients), xerostomia (one patient), esophageal stricture (one patient), pituitary dysfunction (four patients), primary hypothyroidism (one patient), bilateral eighth-nerve deafness (one patient), and carcinoma of the thyroid (one patient). Complications following treatment with electrons to a spinal field are compared with reported complications following treatment with photons to the spinal field. Although short-term reactions were minimal, the authors found no difference in late complications. More sophisticated treatment planning may show such a long-term benefit in the future.