The effect of marital status by age on patients with colorectal cancer over the past decades: a SEER-based analysis.

OBJECTIVE: Marital status has been found as an independent prognostic factor for survival in colorectal cancer (CRC). However, it is unclear whether patients with different marital status have benefited the same from the treatment improvement.

METHODS: We queried the Surveillance, Epidemiology, and End Results (SEER) 9 database for patients diagnosed with CRC from 1975 to 2009. Yearly survival data was presented with overlying loess smoothing lines, stratifying by marital status. We further referred to the SEER 18 database for patients diagnosed with CRC from 1973 to 2014. We also performed yearly data for stage proportion, surgery-performed rate, cancer-specific survival (CSS), and multivariate hazard ratio with overlying loess smoothing lines across all marital status.

RESULTS: Five-year CSS of married, single, and separated/divorced patients showed remarkable increase since 1975; however, survival of widowed patients remained low and no survival gains were observed since 1990. The same trends persisted after stratifying patients by stage and gender. Married and widowed patients tended to have more localized disease and less distant disease compared with the other two groups, and married patients were more likely to receive surgery. Multivariate analysis revealed the hazard ratio of widowed patients dropped dramatically when including age at diagnosis.

CONCLUSIONS: Widowed patients have not benefited substantially from the remarkable treatment improvement over the past four decades, which may be the result of the older age of this particular group. This study is a wake-up call to the medical community for additional care for the widowed patients.