Patterns of care of IMRT usage in postoperative management of uterine cancer.

OBJECTIVE: To analyze the patterns of care regarding intensity modulated radiation therapy (IMRT) usage in the postoperative management of uterine cancer. METHODS: The National Cancer Database was queried to identify women with endometrial adenocarcinoma who underwent hysterectomy followed by external beam radiation between 2004-2012. Descriptive statistics were used to analyze IMRT usage with comparison via the Chi Square test. Overall survival was also compared between IMRT and three dimensional conformal radiation therapy. Multivariable logistic regression and multivariable Cox Regression were used to identify covariables that impact IMRT usage and improved survival respectively. RESULTS: 7839 women were included in this study. IMRT utilization increased from 1.9% in 2004 to 32.4% in 2012 (p<0.001). The adjusted odds ratio (OR) for IMRT in 2012 compared with 2004 was 24.90, 95% CI 15.24-40.67 (p<0.001). Aside from year, other predictors of IMRT usage on multivariate analysis were positive nodes, higher dose, private insurance and higher income. Black race was associated with lower IMRT usage compared to Whites with an OR of 0.60, 95% CI 0.44-0.81 (p=0.001). IMRT was not associated with significantly increased survival (HR 0.86, 95% CI 0.73-1.01, p=0.06). Black race and positive nodes were associated with decreased survival within the group studied whereas private insurance and higher income were associated with improved survival. CONCLUSIONS: In this hospital-based registry, IMRT has significantly increased in utilization for postoperative radiation in uterine cancer between 2004-2012 although not resulting in significantly improved survival. Socioeconomic and racial disparities exist in the allocation of IMRT usage.