Intensity-modulated radiotherapy in high-grade gliomas: clinical and dosimetric results. Academic Article Article uri icon

Overview

MeSH

  • Adult
  • Aged
  • Aged, 80 and over
  • Brain
  • Disease Progression
  • Female
  • Glioblastoma
  • Humans
  • Male
  • Middle Aged
  • Neoplasm Recurrence, Local
  • Oligodendroglioma
  • Radiotherapy Dosage
  • Retrospective Studies

MeSH Major

  • Brain Neoplasms
  • Glioma
  • Radiotherapy, Intensity-Modulated

abstract

  • To report preliminary clinical and dosimetric data from intensity-modulated radiotherapy (IMRT) for malignant gliomas. Fifty-eight consecutive high-grade gliomas were treated between January 2001 and December 2003 with dynamic multileaf collimator IMRT, planned with the inverse approach. A dose of 59.4-60 Gy at 1.8-2.0 Gy per fraction was delivered. A total of three to five noncoplanar beams were used to cover at least 95% of the target volume with the prescription isodose line. Glioblastoma accounted for 70% of the cases, and anaplastic oligodendroglioma histology (pure or mixed) was seen in 15% of the cases. Surgery consisted of biopsy only in 26% of the patients, and 80% received adjuvant chemotherapy. With a median follow-up of 24 months, 85% of the patients have relapsed. The median progression-free survival time for anaplastic astrocytoma and glioblastoma histology was 5.6 and 2.5 months, respectively. The overall survival time for anaplastic glioma and glioblastoma was 36 and 9 months, respectively. Ninety-six percent of the recurrences were local. No Grade IV/V late neurologic toxicities were noted. A comparative dosimetric analysis revealed that regardless of tumor location, IMRT did not significantly improve target coverage compared with three-dimensional planning. However, IMRT resulted in a decreased maximum dose to the spinal cord, optic nerves, and eye by 16%, 7%, and 15%, respectively, owing to its improved dose conformality. The mean brainstem dose also decreased by 7%. Intensity-modulated radiotherapy delivered with a limited number of beams did not result in an increased dose to the normal brain. It is unlikely that IMRT will improve local control in high-grade gliomas without further dose escalation compared with conventional radiotherapy. However, it might result in decreased late toxicities associated with radiotherapy.

publication date

  • March 1, 2006

has subject area

  • Adult
  • Aged
  • Aged, 80 and over
  • Brain
  • Brain Neoplasms
  • Disease Progression
  • Female
  • Glioblastoma
  • Glioma
  • Humans
  • Male
  • Middle Aged
  • Neoplasm Recurrence, Local
  • Oligodendroglioma
  • Radiotherapy Dosage
  • Radiotherapy, Intensity-Modulated
  • Retrospective Studies

Research

keywords

  • Evaluation Studies
  • Journal Article

Identity

Language

  • eng

Digital Object Identifier (DOI)

  • 10.1016/j.ijrobp.2005.05.067

PubMed ID

  • 16458777

Additional Document Info

start page

  • 892

end page

  • 897

volume

  • 64

number

  • 3