Treatment Patterns and Economic Assessment of Systemic Therapy for Metastatic Colorectal Cancer

Introduction: Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the third leading cause of cancer deaths in the United States. The goal of this study was to understand treatment patterns, biomarker testing practices, treatment adherence, and the clinical and economic outcomes associated with chemotherapy for metastatic disease. Methods and Materials: We retrospectively examined electronic health records of patients with metastatic CRC who initiated chemotherapy between 01 January 2007 and 30 June 2011, with follow-up to 30 June 2012. Parameters analyzed included demographics and clinical characteristics, treatment patterns, clinical outcomes, and health care resource utilization. Results: In the analysis, 756 patients were included; median age was 61 years (55% male) at start of first line therapy. The most commonly used regimens in the first, second, and third line were FOLFOX + bevacizumab (46%), FOLFIRI + bevacizumab (23%), and irinotecan + cetuximab (23%) respectively. Adherence to guidelines decreased with increasing line of therapy. When assessed by treatment backbone categories in the third line, outcome measures including overall survival (OS), and time to treatment discontinuation (TTD) were not statistically different between groups. In the multivariable model, body mass index (BMI), performance status, and KRAS were significant predictors of survival. Conclusions: This study provides insight into patterns of care and outcomes of mCRC patients for the aforementioned time period. As treatment options for mCRC evolve, it is valuable to understand the continuum of care to help inform future treatment among candidates for continued therapy.