BackgroundColorectal cancer (CRC) care has improved considerably, particularly since the implementation of a quality of care program centered on national evidence-based guidelines. Formal quality assessment is however still needed. The aim of this research was to identify factors associated with practice variation in CRC patient care.MethodsCRC patients identified from all cancer centers in South-West France were included. We investigated variations in practices (from diagnosis to surgery), and compliance with recommended guidelines for colon and rectal cancer. We identified factors associated with three colon cancer practice variations potentially linked to better survival: examination of ≥12 lymph nodes (LN), non-use and use of adjuvant chemotherapy for stage II and stage III patients, respectively.ResultsWe included 1,206 patients, 825 (68%) with colon and 381 (32%) with rectal cancer, from 53 hospitals. Compliance was high for resection, pathology report, LN examination, and chemotherapy use for stage III patients. In colon cancer, 26% of stage II patients received adjuvant chemotherapy and 71% of stage III patients. 84% of stage US T3T4 rectal cancer patients received pre-operative radiotherapy. In colon cancer, factors associated with examination of ≥12 LNs were: lower ECOG score, advanced stage and larger hospital volume; factors negatively associated were: left sided tumor location and one hospital district. Use of chemotherapy in stage II patients was associated with younger age, advanced stage, emergency setting and care structure (private and location); whereas under-use in stage III patients was associated with advanced age, presence of comorbidities and private hospitals.ConclusionsAlthough some changes in practices may have occurred since this observational study, these findings represent the most recent report on practices in CRC in this region, and offer a useful methodological approach for assessing quality of care. Guideline compliance was high, although some organizational factors such as hospital size or location influence practice variation. These factors should be the focus of any future guideline implementation.