Factors associated with chemotherapy receipt and intensity for stage IV colorectal cancer (CRC): A multihealth system, population-based study.

6519 Background: Little is known about chemotherapy practice patterns for patients with stage IV CRC. METHODS: Cancer Outcomes Research & Surveillance Consortium (CanCORS) is a prospective cohort study including patients with incident CRC sampled from a set of defined populations and health systems. Eligible patients for this analysis (n = 742) had stage IV CRC and abstracted medical record data, including stage, chemotherapy, comorbidity (measured by the Adult Comorbidity Evaluation 27 index), and sociodemographic data. Logistic regression models were used to evaluate factors associated with chemotherapy receipt and intensity. RESULTS: A majority of patients were male (62%) and white (62%). 27% were ≥75 years old, and 14% had severe comorbidity. 34% had private insurance, 32% had public insurance (including Medicare/Medicaid), 18% were Veterans Affairs patients, 4% had no insurance, and 13% were missing insurance information. Overall, 77% received chemotherapy, and 57% received >1 line of therapy. Patients were less likely to receive chemotherapy if they were older (65-74 vs. <55 years = adjusted odds ratio [OR] 0.14, 95%CI 0.06-0.33, p < 0.001; ≥75 vs. <55 years = OR 0.04, 95%CI 0.02-0.64, p < 0.001), or had severe comorbidity (OR 0.38; 95%CI 0.23-0.64; p < 0.001). When treated, patients ≥75 years were more likely to receive capecitabine vs. 5-fluorouracil (5-FU) (p < 0.001), less likely to receive >1 line of therapy (p < 0.001), and less likely to receive oxaliplatin or irinotecan combination therapy vs. a single-agent fluorouracil (p < 0.001). Although only 4% were uninsured, lack of insurance did not appear to be a factor in receipt of chemotherapy. Patients with public vs. private insurance were more likely to receive chemotherapy (OR 2.58; 95%CI 1.49-4.47; p < 0.001) but were less likely to receive combination therapy versus a single-agent 5-FU (p = 0.02). CONCLUSIONS: The elderly are less likely to receive standard therapy. While patients with public insurance are more likely to receive chemotherapy, they are less likely to receive recommended first-line combination regimens. Future research should investigate how insurance coverage and demographics influence physician and patient preferences for advanced CRC treatment. No significant financial relationships to disclose.

Duke Scholars

Author Steven C. Grambow Biostatistics & Bioinformatics, Division of Biostatistics

Author Leah L Zullig Population Health Sciences