Debate Over Brain Cancer Rx Continues

Avastin found to extend glioblastoma patient survival in population study

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Avastin (bevacizumab) is approved to treat a number of different cancers, including the most common form of brain cancer. A newly released study looked at how long people with the disease lived before and after this medication's approval.

A large population study found that people diagnosed with glioblastoma lived significantly longer after the conditional approval of Avastin than did patients who didn’t have access to the medication.

But one of the nation’s leading brain cancer specialists disputes these findings.

"Ask your oncologist about new cancer medications."

Derek Johnson, MD, a neuro-oncologist at Mayo Clinic Cancer Center in Rochester, Minnesota, conducted this study that analyzed glioblastoma survival data before and after the approval of Avastin.

While treatment advances have assisted the roughly 3,000 Americans diagnosed with glioblastoma every year, the disease progresses when tumors invariably return after initial therapy. When this occurs, life expectancy is measured in a matter of months.

Avastin received conditional US Food and Drug Administration (FDA) approval in 2009 for the treatment of glioblastoma after initial therapy fails.

Researchers in this study looked at data from National Cancer Institute (NCI) Surveillance, Epidemiology and End Results (SEER) database to examine survival of 1,715 glioblastoma patients in 2006, 1,924 patients who died in 2008 and 1,968 individuals who succumbed to the disease in 2010.

The study found that the median (middle) survival was eight months in 2006, seven months in 2008 and nine months in 2010.

There were significant differences in survival between 2008 (pre-Avastin) and 2010 (post-Avastin) in every age subgroup except the group aged 18 to 39 years. 

Acknowledging that there has been a great deal of debate regarding the effectiveness of Avastin, Dr. Johnson said in a prepared statement, “Our study found that, at the population level, treatment strategies involving bevacizumab prolonged survival in patients with progressive glioblastoma."

Keith L. Black, MD, chair and professor of Cedars-Sinai’s Department of Neurosurgery, director of the Cochran Brain Tumor Center, director of the Maxine Dunitz Neurosurgical Institute and the Ruth and Lawrence Harvey Chair in Neuroscience, disagrees with these conclusions.

“This study is of interest, but as a ‘population-based’ report, it is not as persuasive as others that are stronger scientifically — prospective [follows patients over time] or randomized [compares two groups taking different therapies] studies — which reach a different conclusion.”

Dr. Black continued, “The study’s finding that bevacizumab improves survival of patients with glioblastoma multiforme contradicts recent prospective studies showing that survival does not improve. In one study, quality of life measures were found to be lower in patients treated with the drug.”

The study Dr. Black is referring to is one that was presented at the American Society of Clinical Oncology annual meeting in June 2013. That study, from the University of Texas MD Cancer Center, found that when added to chemotherapy, Avastin did not prolong the lives of glioblastoma patients.

The current study was published in the journal Cancer.

No specific funding information was provided and no conflicts of interest were disclosed.

Review Date: 
August 20, 2013
Last Updated:
December 30, 2013