Intracranial Subependymoma: A SEER Analysis 2004-2013

Subependymomas are rare, slow-growing, benign tumors. Because they are scarce, knowledge relating to survival remains lacking. Consequently, we explore the SEER database to evaluate prognostic and treatment factors associated with intracranial subependymoma.

With the SEER-18 registry database, information from all patients with intracranial subependymoma diagnosed during 2004-2013 were extracted, including age, sex, race, occurrence of surgery, extent of primary surgery, receipt of radiation, tumor size, and follow-up data. Age-adjusted incidence rates, overall survival, and cause-specific survival were calculated. Cox proportional hazards model was used for both univariate and multivariate analyses.

Four hundred sixty-six cases were identified. The overall incidence of intracranial subependymoma is 0.055 per 100,000 person-years (95% confidence interval, 0.05-0.06). Through multivariate analysis, age <40 years (hazard ratio [HR], 0.21; P = 0.03), female sex (HR, 0.34; P = 0.03), location within ventricles or near brainstem (HR, 0.49; P = 0.04), and occurrence of surgery (HR, 0.50; P = 0.02) were significant independent positive prognostic factors. Receipt of radiation did not show a significant relationship.

Clinical factors such as younger age, female sex, and location within ventricles or near brain stem demonstrated positive relationship with overall survival. For treatment options, surgery remains a mainstay option. No support for radiation therapy was identified.