Adult Brain Tumors Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Treatment Option Overview
As is the case with several other specialized operations [9,10] in which postoperative mortality has been associated with the number of procedures performed, postoperative mortality after surgery for primary brain tumors may be associated with hospital and/or surgeon volume. Using the Nationwide Inpatient Sample hospital discharge database for the years 1988 to 2000, which represented 20% of inpatient admissions to nonfederal U.S. hospitals, investigators found that large-volume hospitals had lower in-hospital mortality rates after craniotomies for primary brain tumors (odds ratio [OR] = 0.75 for a ten-fold higher caseload; 95% confidence interval [CI], 0.62–0.90) and after needle biopsies (OR = 0.54; 95% CI, 0.35–0.83). For example, although there was no specific sharp threshold in mortality outcomes between low-volume hospitals and high-volume hospitals, craniotomy-associated in-hospital mortality was 4.5% for hospitals with five or fewer procedures per year and 1.5% for hospitals with at least 42 procedures per year. In-hospital mortality rates decreased over the study years (perhaps because the proportion of elective nonemergent operations increased from 45% to 57%), but the decrease was more rapid in high-volume hospitals than in low-volume hospitals. High-volume surgeons also had lower patient in-hospital mortality rates after craniotomy (OR= 0.60; 95% CI, 0.45–0.79). As with any study of volume-outcome associations, these results may not be causal because they may be affected by residual confounding factors, such as referral patterns, private insurance, and patient selection, despite multivariable adjustment.
Radiation therapy has a major role in the treatment of patients with high-grade gliomas. A systematic review and meta-analysis of five randomized trials (plus one trial with allocation by birth date) comparing postoperative radiation therapy (PORT) with no radiation therapy showed a statistically significant survival advantage with radiation (risk ratio = 0.81; 95% CI, 0.74–0.88).[Level of evidence: 1iiA] Based on a randomized trial comparing 60 Gy (in 30 fractions over 6 weeks) to 45 Gy (in 25 fractions over 4 weeks) that showed superior survival in the first group (12 months vs. 9 months median survival; hazard ratio [HR] = 0.81; 95% CI, 0.66–0.99), 60 Gy is the accepted standard dose of EBRT for malignant gliomas.[Level of evidence: 1iiA]
As with surgical resection, attempts have been made to preserve normal brain function using techniques intended to deliver a full therapeutic dose of radiation to the tumor and a small surrounding margin, while minimizing dose to most of the brain (e.g., 3–dimensional conformal radiation or intensity-modulated radiation therapy [IMRT] and radiosurgery). However, it is not clear that these techniques affect overall survival (OS) compared to standard EBRT. There are no randomized trials directly comparing the effects of these techniques as primary PORT on survival.