Are there variations in adherence to colorectal cancer clinical guidelines depending on treatment place and recommendation novelty? The French EvaCCoR observational study.

BACKGROUND: Studies have shown clinical practices variation between centers in colorectal cancer (CRC) management. After the implementation of national cancer plans, we tested for differences in center and patients' socioeconomic position (SEP)-related variation in CRC guidelines. METHODS: All patients aged 18 years and over, cared for a first CRC in 2010 in Southwest of France. We used mixed effect model to test for center-related heterogeneity (CRH) in recommendation, from the oldest to the more recent: (1) at least 12 lymph nodes analysed for stage II, (2) the prescription of adjuvant chemotherapy stage III and (3) the assessment of CRC molecular phenotype regarding KRAS status for stage IV. Patients' SEP was approached by an ecological social deprivation index. RESULTS: We found: higher adherence for the oldest than for the most recent recommendations; no CRH in recommendation No. 2 but lower adherence in academic centers; a CRH for recommendations No. 1 and 3; no SEP-related differences in clinical practices. CONCLUSION: Results showed that older recommendations have higher adherence but did not support increasing influence of centers characteristics and CRH as recommendations are more recent.