Adult Brain Tumors Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Treatment Option Overview
Two primary goals of surgery include:
- Establishing a histologic diagnosis.
- Reducing intracranial pressure by removing as much tumor as is safely possible to preserve neurological function.
However, total elimination of primary malignant intraparenchymal tumors by surgery alone is rarely achievable. Therefore, intraoperative techniques have been developed to reach a balance between removing as much tumor as is practical and the preservation of functional status. For example, craniotomies with stereotactic resections of primary gliomas can be done in cooperative patients while they are awake, with real-time assessment of neurologic function. Resection proceeds until either the magnetic resonance imaging (MRI) signal abnormality being used to monitor the extent of surgery is completely removed or subtle neurologic dysfunction appears (e.g., slight decrease in rapid alternating motor movement or anomia). Likewise, when the tumor is located in or near language centers in the cortex, intraoperative language mapping can be performed by electrode discharge-induced speech arrest while the patient is asked to count or read.
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 tenfold 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 in-hospital patient 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.