Extensive Resection Linked to Improved Survival in Glioblastoma

Gross total resection is difficult to achieve due to complexities involved with brain cancer.

More extensive resection was associated with higher survival rates in patients with glioblastoma multiforme (GBM), according to a recent study.

Treatment options for GBM include medical, surgical, and radiation therapy, and the surgical treatment options can range from minimally invasive biopsy to a craniotomy, with the goal of gross total resection (GTR). However, because of the complexities of the brain it makes surgery difficult and not every patient receives an aggressive resection.

In a study published in JAMA Oncology, researchers used a meta-analysis of 37 studies that totaled 41,117 patients, to compare GTR with subtotal resection (STR) or biopsy with overall and progression free survival.

The results of the study found a lower relative risk of death at 1 and 2 years. The study authors said that GTR may increase the likelihood of 1-year survival compared with STR by approximately 61%. Furthermore, it may increase the likelihood of 2-year survival by about 19%.

When researchers compared the 1-year risk of mortality for STR versus biopsy, they found that the mortality risk was reduced for any resection compared with biopsy at 1 and 2 years. The reduction in mortality was associated with an increase in extent of resection, overall. Furthermore, GTR was associated with a decrease in disease progression over 1 year.

Authors noted that the findings should be interpreted in the context of important caveats, which includes the number of factors that differed among the GTR and STR groups. Additionally, the extent of tumor resection was defined by authors in the studies, which was often inaccurate.

“Although the available studies are retrospective and mostly carry a high risk for bias and confounding, an overwhelming consistency of the evidence (including three class 2 studies) supports the superiority of GTR over STR and biopsy,” study authors wrote. “...Therefore, when clinically feasible, the body of literature favors GTR in all patients with newly diagnosed GBM.”