Sex-Based Differences in Treatment and Prognosis for Adult Pineoblastoma.

PURPOSE/OBJECTIVE(S) Adult pineoblastoma is a rare but aggressive tumor with poor prognosis despite multimodality treatment. The impact of sociodemographic factors on care and outcome is poorly understood, and prior studies were limited by small sample sizes. Emerging evidence implicates the role of sex differences in the prognosis of aggressive brain tumors such as glioblastoma. This study aims to analyze the impact of sociodemographic factors, including sex, on the treatment and clinical outcome of adult pineoblastoma. MATERIALS/METHODS Patients aged 18 years and older with pineoblastoma diagnosed from 2004 to 2016 were identified from the National Cancer Database (NCDB). Patients with unknown status for insurance, income quartile, education quartile, urban/rural residence, distance from hospital, treatment, or overall survival (OS) were excluded. OS was evaluated with the Kaplan-Meier and Cox proportional hazards methods using SPSS. Logistic regression was performed to determine the correlation with treatment. RESULTS A total of 374 patients with pineoblastoma were identified for analysis. The median age was 41 years. The median follow-up time was 49.2 months. 25.1% patients were uninsured or had Medicaid, 76.2% patients were white, and 18.4% patients were from households with income in the lowest quartile based on 2016 U.S. census data. Upon multivariate analysis adjusting for Charlson-Deyo score, only age, sex, andtreatment were statistically associated with OS. Increased age at diagnosis was associated with poorer OS (HR 1.023, 95% CI 1.011-1.035, P < 0.001) and male patients had worse OS (HR 1.662, 95% CI 1.156-2.389, P = 0.006) compared to female patients. Any surgical and radiation treatment, individually or combined, was beneficial for OS compared with no treatment. Surgery alone was comparable to combined surgery and radiation; radiation alone was statistically associated with lower OS (HR = 1.697, 95% CI 1.081-2.663, P = 0.021) compared to combined surgery and radiation. Using logistic regression, male patients were less likely to receive surgical intervention (OR 0.5, 95% CI 0.31-0.82, P = 0.006). CONCLUSION This NCDB study represents the largest analysis of adult pineoblastoma to date and demonstrated statistically significant sex-based differences of surgical intervention and patient outcomes. The association of radiation-only treatment with worse OS is likely the result of more aggressive cases contraindicated for surgery and potentially contributes to the poorer prognosis of male patients. Future studies examining the biological underpinnings of these differences may help tailor therapeutic decision and improve clinical outcome for adult pineoblastoma.