Disease control and ototoxicity using intensity-modulated radiation therapy tumor-bed boost for medulloblastoma.


Journal Article

PURPOSE: We previously reported excellent local control for treating medulloblastoma with a limited boost to the tumor bed. In order to decrease ototoxicity, we subsequently implemented a tumor-bed boost using intensity-modulated radiation therapy (IMRT), the clinical results of which we report here. PATIENTS AND METHODS: A total of 33 patients with newly diagnosed medulloblastoma, 25 with standard risk, and 8 with high risk, were treated on an IMRT tumor-bed boost following craniospinal irradiation (CSI). Six standard-risk patients were treated with an institutional protocol with 18 Gy CSI in conjunction with intrathecal iodine-131-labeled monoclonal antibody. The majority of patients received concurrent vincristine and standard adjuvant chemotherapy. Pure-tone audiograms were graded according to National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. RESULTS: Median age was 9 years old (range, 4-46 years old). Median follow-up was 63 months. Kaplan-Meier estimates of progression-free survival (PFS) and overall survival (OS) rates for standard-risk patients who received 23.4 or 36 Gy CSI (not including those who received 18 Gy CSI with radioimmunotherapy) were 81.4% and 88.4%, respectively, at 5 years; 5-year PFS and OS rates for high-risk patients were both 87.5%. There were no isolated posterior fossa failures outside of the boost volume. Posttreatment audiograms were available for 31 patients, of whom 6%, at a median follow-up of 19 months, had developed Grade 3 hearing loss. CONCLUSION: An IMRT tumor-bed boost results in excellent local control while delivering a low mean dose to the cochlea, resulting in a low rate of ototoxicity.

Full Text

Cited Authors

  • Polkinghorn, WR; Dunkel, IJ; Souweidane, MM; Khakoo, Y; Lyden, DC; Gilheeney, SW; Becher, OJ; Budnick, AS; Wolden, SL

Published Date

  • November 2011

Published In

Volume / Issue

  • 81 / 3

Start / End Page

  • e15 - e20

PubMed ID

  • 21481547

Pubmed Central ID

  • 21481547

Electronic International Standard Serial Number (EISSN)

  • 1879-355X

International Standard Serial Number (ISSN)

  • 0360-3016

Digital Object Identifier (DOI)

  • 10.1016/j.ijrobp.2010.11.081


  • eng