Surveillance, Epidemiology, and End Results database and propensity score matching analysis of postoperative radiotherapy for non malignant meningioma: A retrospective cohort study.

BACKGROUND: The clinical effect of postoperative radiotherapy (PORT) in non-malignant meningioma (NMM) has not been well explored.

METHODS: A total of 8629 patients with NMM (surgery alone group: n = 7716, postoperative radiotherapy group: n = 913) were obtained from the Surveillance, Epidemiology, and End Results database. Patient profiles were matched by 1:1 propensity score matching (PSM). Logistic regression analysis was performed to identify factors associated with PORT versus surgery alone (SA). Univariate and multivariate Cox regression analyses determined prognostic variables with overall survival (OS) in NMM. Subgroup analyses were performed with Cox proportional hazards regression models.

RESULTS: All the SA (n = 7716) and PORT (n = 913) groups were included. Women with PORT (66.3%) and SA (70.9%) were almost twice as likely as men, and tumors with benign behaviors in the SA group were almost seven times more frequent than those with malignant characteristics. We explored the demographic, clinical characteristics, and prognostic factors in NMM. Laterality, surgery, tumor size, diagnosis year, age, and tumor behavior were associated with PORT versus SA. Patients treated with PORT had better OS than those treated with SA (p = 0.03). After PSM, PORT remained comparable to SA (hazard ratio 0.56, 95% confidence interval 0.35-0.88, p = 0.013). In the subgroup analysis of PORT treatment, borderline malignant behavior increased the death risk by 23%, while other variables did not have a significant clinical benefit (p > 0.05).

CONCLUSIONS: Borderline malignant behavior should be considered seriously, and the PORT regimen should be actively implemented for patients with benign meningiomas.