The validity of administrative data and patterns of chemotherapy use among elderly colorectal cancer patients Public Deposited

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  • March 21, 2019
  • Lund, Jennifer L.
    • Affiliation: Gillings School of Global Public Health, Department of Epidemiology
  • Chemotherapy represents an integral part of the treatment plan for many cancer patients, proven to decrease recurrence and overall mortality. Recent trials demonstrated that adding oxaliplatin to 5-fluorouracil/leucovorin significantly improved survival for stage III colon cancer patients. However, few studies have examined the translation of these findings into routine practice, particularly among the elderly, who are underrepresented in trials. Two population-based data sources were linked to assess the utility of Medicare claims in identifying chemotherapy and specific agents administered to elderly stage II/III colorectal cancer (CRC), in-situ/early stage breast, non-small cell lung, and ovarian cancer patients. The National Cancer Institute's Patterns of Care (POC) studies collected data on chemotherapy by reviewing hospital and medical records and contacting physicians. POC data were linked and compared to Medicare claims and measures of agreement and validity were estimated. Using validated definitions, we constructed a cohort of stage II/III CRC patients from the Surveillance, Epidemiology, and End Results program (SEER)-Medicare linked database to 1) estimate trends in the utilization of agents over time and 2) identify patient, physician, and hospital characteristics associated with the receipt of oxaliplatin using Poisson regression models and a generalized estimating equation (GEE) strategy for non-nested clustering. Overall, the sensitivity and specificity of Medicare claims to identify any chemotherapy were high; however, we found variation across agents, sites and administration modalities. Shifts in utilization of specific agents were seen from 2000-2007, with increasing oxaliplatin and capecitabine use. Younger age, being married, fewer comorbidities, low-poverty areas, colon cancer diagnosis, and stage III disease were associated with oxaliplatin use. Validated Medicare definitions identified a substantial increase in oxaliplatin utilization from 2004-2007 for both on- and off-label indications. Patient characteristics were most influential in explaining the variation in oxaliplatin receipt. Off-label use of chemotherapeutic agents was relatively common. Physicians should carefully weigh the minimal (if any) or unknown benefits of treatment against potentially serious side effects when deciding whether to treat a patient off-label.
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  • In Copyright
  • "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Gillings School of Global Public Health (Epidemiology)."
  • Stürmer, Til
Degree granting institution
  • University of North Carolina at Chapel Hill
Place of publication
  • Chapel Hill, NC
  • Open access

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