Determinants of NCI Cancer Center attendance in Medicare patients with lung, breast, colorectal, or prostate cancer.

BACKGROUND: Geographic access to NCI-Cancer Centers varies by region, race/ethnicity, and place of residence, but utilization of these specialized centers has not been examined at the national level in the U.S. This study identified determinants of NCI-Cancer Center attendance in Medicare cancer patients.
METHODS: SEER-Medicare (Surveillance Epidemiology and End Results) data were used to identify individuals with an incident cancer of the breast, lung, colon/rectum, or prostate from 1998-2002. NCI-Cancer Center attendance was determined based on utilization claims from 1998-2003. Demographic, clinical, and geographic factors were examined in multilevel models. We performed sensitivity analyses for the NCI-Cancer Center attendance definition.
RESULTS: Overall, 7.3% of this SEER-Medicare cohort (N = 211,048) attended an NCI-Cancer Center. Travel-time to the nearest NCI-Cancer Center was inversely related to attendance, showing 11% decreased likelihood of attendance for every 10 minutes of additional travel-time (OR = 0.89, 95%CI 0.88-0.90). Receiving predominantly generalist care prior to diagnosis was associated with a lower likelihood of attendance (OR = 0.79, 95%CI 0.77-0.82). The other factors associated with greater NCI-Cancer attendance were later stage at diagnosis, fewer comorbidities, and urban residence in conjunction with African-American race.
CONCLUSIONS: Attendance at NCI-Cancer Centers is low among Medicare beneficiaries, but is strongly influenced by proximity and general provider care prior to diagnosis. Other patient factors are predictive of NCI-Cancer Center attendance and may be important in better understanding cancer care utilization.