Importance of tumor grade in esthesioneuroblastoma survival: a population-based analysis.

IMPORTANCE There is a need for larger studies characterizing the effect of tumor grade on survival for patients with esthesioneuroblastoma. OBJECTIVE To investigate prognostic factors for survival in patients diagnosed with esthesioneuroblastoma, including emphasis on tumor grade. DESIGN, SETTING, AND PARTICIPANTS Retrospective, population-based cohort study of patients in the Surveillance, Epidemiology, and End Results (SEER) tumor registry who were diagnosed with esthesioneuroblastoma from January 1, 1973, to January 1, 2010. The last date of survival follow-up was 2013. MAIN OUTCOMES AND MEASURES Overall and disease-specific survival. RESULTS The cohort included 281 patients with a mean age of 52 years. There were 154 males (54.8%) and 127 females (45.2%). Kaplan-Meier analysis demonstrated an overall and disease-specific survival rate of 61% and 70% at 5 years and 50% and 64% at 10 years, respectively. Multivariable Cox regression analysis showed that advanced tumor grade and modified Kadish stage (hazard ratio, 4.930; 95% CI, 2.635-9.223; P = .001) portended worse disease-specific survival, and radiation therapy (hazard ratio, 0.499; 95% CI, 0.272-0.916; P = .03) improved disease-specific survival. Patients with low-grade tumors (grades I and II) demonstrated an overall and disease-specific survival rate of 84% and 92% at 5 years and 67% and 87% at 10 years, respectively. Multivariable analysis of low-grade tumors only revealed receiving surgery (P = .004) as an independent positive predictor of disease-specific survival. High-grade tumors (grades III and IV) demonstrated overall and disease-specific survival of 40% and 50% at 5 years and 34% and 43% at 10 years, respectively. Multivariable analysis of high-grade tumors showed modified Kadish stage (hazard ratio, 2.025; 95% CI, 1.430-2.866; P < .001) predicted worse disease-specific survival, and radiation therapy (hazard ratio, 0.433; 95% CI, 0.228-0.864; P = .02) independently predicted improved disease-specific survival. CONCLUSIONS AND RELEVANCE Here, to our knowledge, we report the largest study investigating prognostic factors for survival, with the inclusion of tumor grade, in patients diagnosed with esthesioneuroblastoma. Patients with high-grade tumors had substantially worse survival rates than patients with low-grade tumors. Multivariable analysis revealed only receiving surgery as an independent predictor of disease-specific survival for patients with low-grade tumors, while modified Kadish stage and postoperative radiation therapy were significant factors in predicting disease-specific survival in patients with high-grade tumors. This study highlights the growing evidence that tumor grade should be a key factor in predicting survival in patients with esthesioneuroblastoma, and that adjuvant radiation therapy improves survival rates among patients with high-grade, but not low-grade, tumors.