How does comorbidity affect colon cancer patients' care trajectory? Results from the French EvaCCoR cohort study.

OBJECTIVE: Due to their advanced age in average, colon cancer patients are likely to be exposed to comorbidity. However, the influence of comorbidity on patients' care trajectory and survival is largely under-explored. Hence, we investigate the effect of comorbidity on patients care trajectory and survival based on an observational study in "real-life" setting. METHODS: This prospective observational study in two French regions includes patients aged over 18 and firstly treated for a colon cancer, stage II and III, diagnosed between 1st January and 31st December 2010. We assessed the influence of comorbidity (severe vs moderate or none), using the Charlson Comorbidity Index, on overall survival and patients' management steps. RESULTS: We analyzed 762 patients. We found comorbidity to be associated with adjuvant treatment delivery with a longer delay between surgery and chemotherapy initiation among patients with severe comorbidity. Severe comorbidity had an independent detrimental effect on overall survival that is slightly downsized after adjustment for adjuvant treatment delivery. CONCLUSION: Using observational "real-life" data, we showed that comorbidity impacts the colon cancer patients' care trajectory directly but also through indirect pathways involving adjuvant chemotherapy delivery. However, further studies are needed to better understand this mechanism.