Adjuvant chemotherapy in stage III colon cancer: guideline implementation, patterns of use and outcomes in daily practice in The Netherlands

Little is known about how well guidelines about adjuvant chemotherapy in colon cancer are followed in daily practice. We evaluated the current guideline, which is based on the MOSAIC trial, by examining implementation, treatment patterns and disease-free survival. We analysed a population-based cohort of 391 patients treated with adjuvant chemotherapy for stage III colon cancer in 2005-2006. Data were gathered from the Dutch Cancer Registry and medical records of 19 hospitals. Patients were classified according to whether or not they fulfilled MOSAIC trial eligibility criteria. The administered regimens were: fluorouracil-leucovorin (17 patients), capecitabine (93), fluorouracil-leucovorin plus oxaliplatin (145), and capecitabine plus oxaliplatin (136). After its inclusion in national guidelines, oxaliplatin was prescribed in 16 hospitals within six months. Patients receiving oxaliplatin were younger and had less comorbidity than other patients. Dose schedules corresponded well with guidelines. Two-year disease-free survival probability of oxaliplatin patients meeting MOSAIC eligibility criteria was 78.4% (95% CI 72.5-84.3), which was comparable to MOSAIC trial results. Guidelines for adjuvant chemotherapy in stage III colon cancer are generally well followed in daily practice. However, uncertainty remains regarding the optimal treatment of elderly patients and patients with comorbidities, which underscores the need for practical clinical trials including these patients