Patients presenting with nonskull base lesions were at
double the risk for grade 2 or 3 tumors as patients with skull base lesions,
according to study results.
Researchers from one US site aimed to evaluate risk
factors for higher-grade tumors in a cohort of 378 patients presenting with
histologically confirmed meningioma, central pathology grading according to WHO
guidelines, and tumor location confirmed with preoperative imaging.
Univariate analysis results indicated that nonskull base
lesions were more likely than skull base lesions to be associated with grade 2
or 3 tumors, 27% vs. 12% (P>.001). Multivariate analysis results
indicated that nonskull base lesions carried twice the risk for grade 2 or 3
tumors as skull base lesions (OR=2.13; 95% CI, 1.2-3.8).
Men were at greater risk for grade 2 or 3 tumors
compared with women, 30% vs. 14% (P>.001), despite constituting 30%
of the study population. Men had a twofold risk for higher grade tumors
compared with women, according to multivariate analysis results (OR=2.10; 95%
CI, 1.2-3.8).
Surgery for interval growth or atypical features
revealed in an MRI was performed in less than 3% of patients. However, more
than 97% of patients in the cohort underwent surgery for a tumor larger than 3
cm or for clinically debilitating symptoms.
Patients who had previously undergone tumor excision
were more likely to develop higher-grade tumors, according to univariate
analysis (50% vs. 16%; P>.001). Prior surgery remained linked to
higher-grade tumor development in a multivariate analysis (OR=3.5; 95% CI,
1.5-8).
Prior radiation therapy, the presence of a preoperative
deficit and age older than 65 years were significantly associated with
higher-grade tumors in univariate but not multivariate analyses.
The study was conducted because grade 2 and 3
meningiomas are more likely to result in recurrence than grade 1 meningiomas
after surgery and/or external irradiation, according to the researchers, who
said earlier assessment of the nature of the tumor is necessary as noninvasive
treatments become more useful.