Lower treatment intensity and poorer survival in metastatic colorectal cancer patients who live alone

BACKGROUND: Socioeconomic status (SES) and social support influences cancer survival. If SES and social support affects cancer treatment has not been thoroughly explored. METHODS: A cohort consisting of all patients who were initially diagnosed with or who developed metastatic colorectal cancer (mCRC, n=781) in three Scandinavian university hospitals from October 2003 to August 2006 was set up. Clinical and socioeconomic data were registered prospectively. RESULTS: Patients living alone more often had synchronous metastases at presentation and were less often treated with combination chemotherapy than those cohabitating (HR 0.19, 95% CI 0.04–0.85, P=0.03). Surgical removal of metastases was less common in patients living alone (HR 0.29, 95% CI 0.10–0.86, P=0.02) but more common among university-educated patients (HR 2.22, 95% CI 1.10–4.49, P=0.02). Smoking, being married and having children did not influence treatment or survival. Median survival was 7.7 months in patients living alone and 11.7 months in patients living with someone (P<0.001). Living alone remained a prognostic factor for survival after correction for age and comorbidity. CONCLUSION: Patients living alone received less combination chemotherapy and less secondary surgery. Living alone is a strong independent risk factor for poor survival in mCRC.