Increase in time to initiating cancer therapy and association with worsened survival in curative settings: A U.S. analysis of common solid tumors.

Abstract

6557 Background: Increase in time to treatment initiation (TTI) for new cancer diagnoses causes patient distress and may adversely affect outcomes. We investigated trends in TTI for common solid tumors treated with curative intent, determinants of delayed TTI and impact on overall survival. Methods: We utilized population-based, prospective data from the National Cancer Database for newly diagnosed US patients with early-stage breast, prostate, lung, colorectal, renal and pancreas cancers from 2004-13. TTI was defined as days between diagnosis of cancer and first treatment (surgery, systemic or radiation therapy). Negative binomial regression and Cox proportional hazard models were used for analysis. Results: The study population of 3,672,561 patients included breast (N = 1,368,024), prostate (N = 944,246), colorectal (N = 662,094), non-small cell lung (NSCLC)(N = 363,863), renal(N = 262,915) and pancreas (N = 71,419) cancers. Median TTI increased from 21 days in 2004 to 29 days in 2013 (P < 0.0001). Aside from year, determinants of delays included care at academic centers and change in treating facility. Increased TTI was associated with worsened overall survival (OS) for stages I and II breast, lung, renal, and pancreas cancers, and stage II colorectal cancers, with hazard ratios per week of delay ranging from1.005 (1.002-1.008) to 1.030 (1.025-1.035), adjusting for comorbidities and other variables. Prolonged TTI ( > 6 wks) was associated with substantially worsened OS e.g., 5-yr OS for stage I NSCLC was 56% (±0.2) for TTI ≤ 6wks v 43% (±0.2) for TTI > 6 wks and for stage I pancreas was 38% (±0.6) v 29% (±1) respectively (P < 0.0001 for both). Conclusions: TTI has lengthened significantly over recent years, associated with multiple factors. Increase in TTI is associated with substantial increase in mortality ranging from 0.5-3.2% per week of delay in curative settings such as early-stage breast, lung and pancreas cancers. Simplifying access and navigation of complex health systems is essential to diminish this apparently iatrogenic impact on outcomes.