Sunday, February, 12, 2012

Brain Tumors: Primary - Surgery

Table of Contents

Conventional Radiotherapy

Conventional radiotherapy uses external beams aimed directly at the tumor and is usually recommended for large or infiltrating tumors. It begins about a week after surgery and continues on an outpatient basis 5 days per week for 6 weeks. Older adults tend to have a more limited response to external-beam radiation therapy than younger people. Conventional external-beam radiation techniques include:

  • Three-dimensional conformal radiation therapy (3D-CRT) uses computer-generated imaging scans to map the tumor’s location. Radiation beams are then used that conform to the three-dimensional shape of the tumor.
  • Intensity-modulated radiation therapy (IMRT) is a more advanced and higher-dose form of 3D-CRT.
  • Conformalproton beam radiation therapy is also similar to 3D-CRT but uses proton beams instead of x-ray energy. It is not yet widely available.

Stereotactic Radiosurgery

Stereotactic radiosurgery, also called stereotactic radiotherapy or stereotaxy, is an alternative to conventional radiotherapy that allows highly targeted radiation to be delivered directly to small tumors while avoiding healthy brain tissue. The term radiosurgery is used because the destruction is so precise that it acts almost like a surgical knife. Benefits of stereotactic radiosurgery include:

  • Stereotaxy allows precisely focused, high-dose beams to be delivered to gliomas smaller than 1.25 inches in diameter with less damage to surrounding tissues.
  • Stereotactic radiosurgery can help reach small tumors located deep in the brain that were previously considered inoperable.
  • Sometimes with stereotaxy only a single treatment may be needed.
  • Unlike traditional radiotherapy, stereotactic radiotherapy can be repeated, so it is useful for recurrent tumors when a patient has already received standard radiation treatments.
  • Combining stereotaxy with techniques that gauge speech and other mental functions in patients who are awake during the procedure can allow removal of brain tissue with a lower risk for complications in areas that affect such functioning.

The Planning Procedure. Stereotactic radiosurgery usually begins with a series of steps designed to plan the radiation target:

Review Date: 10/21/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)