Radiation for medulloblastoma adjusted to prevent recurrence to the cribriform plate region.

In a recent survey of the recurrence pattern in 40 medulloblastoma patients treated at Memorial Hospital between 1970 and 1979, 15% of all recurrences were in the region of the cribriform plate, which is an area that is undertreated with commonly employed radiation therapy techniques. The authors, therefore, modified their technique to increase the dose in this area. They report on the initial results in 15 subsequent patients treated with this modification. Ten of the 15 patients had localized tumors (Groups I and II) and 8 of these patients are alive disease-free compared with 7 of 17 Group I and II patients treated between 1970 and 1979. Three of five patients with disseminated tumors (Groups III and IV) are alive disease-free compared with none in the previous series. Although the period of follow-up is relatively short (median, 32 months), the overall survival of patients with medulloblastoma seems to be improved with additional radiation to the region of the cribriform plate. No side effects attributable to this modification were observed. In the opinion of the authors, this modification should be used routinely in patients with medulloblastoma.