N. J. Lanzotti1, W. E. Zahnd1, J. F. Tseng2, J. D. Mellinger1, S. Ganai1 2Beth Israel Deaconess Medical Center, Harvard Medical School,Department Of Surgery,Boston, MA, USA 1Southern Illinois University School Of Medicine,Department Of Surgery,Springfield, IL, USA
Introduction:
While regionalization has been advocated for pancreas cancer due to volume-outcome relationships, it is uncertain whether centralization of care leads to access disparities for patients at greater distance from surgical services. We hypothesize that pancreas cancer patients will travel further than breast cancer patients, and that increased travel distance may negatively impact survival.
Methods:
A retrospective cohort study of the National Cancer Database from 1998-2012 was performed to assess the role of travel distance in patients with early-stage cT1-2N0 breast cancer (n=882,791) and cT1-2N0 pancreatic cancer (n=75,233). Travel distance by region was calculated for each group. Multivariable Cox regression was performed evaluating the impact of travel distance on survival controlling for age, gender, race, pathologic stage, facility type, income, insurance, region, and rural-urban designation. Travel distance was analyzed as a categorical variable (0-25 miles, 25-50 miles, 50–100 miles, 100–500 miles, and >500 miles).
Results:
Mean distance traveled was 20.6±86.3 miles for breast cancer and 46.6±151.0 miles for pancreas cancer (p<0.001). Median travel distance for pancreas cancer [12.4 miles (interquartile range, IQR 4.8-36.9)] was significantly greater than for breast cancer [8.0 miles (IQR 3.8-16.8)] across all regions (Figure, medians with IQR error bars). Travel distance differences between cancers varied by region, with New England having the smallest breast-pancreas differential (Δmedian, 1.8 miles; Δ75th%ile, 8.7 miles) and West North Central having the largest (Δmedian, 13.4 miles; Δ75th%ile, 52.7 miles). Outcome was associated with travel distance, with greatest survival benefit noted for patients with travel distance exceeding 500 miles for both breast (HR 0.80; 95% CI, 0.73-0.88; p<0.001) and pancreas cancer (HR 0.88; 95% CI, 0.81-0.95; p<0.001) compared to travel distances under 25 miles. Accounting for geography, heterogeneity in survival was noted between regions for both cancers. Rural location negatively impacts pancreas cancer (HR 1.05; 95% CI, 1.02-1.08; p<0.001), but not breast cancer survival (HR 0.98; 95% CI. 0.96-0.99; p=0.04).
Conclusion:
Contrary to our hypothesis, travel at extremes beyond the median is associated with better long-term survival for both early-stage breast and pancreatic cancer. The impact of travel distance may be influenced by region, rurality, insurance, and SES, and may also be an indicator of likelihood of receiving highly specialized care. Data are limited to those who sought treatment at an NCDB facility and likely reflect selection bias. Further exploration of access disparities in cancer care is warranted.
