Colorectal cancer survival: Results from a hospital-based cancer registry

Introduction: colorectal cancer is one of the most common malignancies in developed countries. Data on specific and 10-year survival are scarce. This study analyzes overall and disease-specific survival for patients with colorectal cancer and assesses the value of clinical factors on disease-specific survival. Methods: a retrospective cohort study of newly diagnosed invasive colorectal cancer cases diagnosed from 1992 to 2007 were identified through the Hospital del Mar Cancer Registry. Five- and 10-year survival functions were estimated using Kaplan-Meier method. Cox proportional hazard models were used to assess prognostic factors. Results: a total of 2,080 patients with colorectal cancer were identified. The median age at diagnosis was 72 years and 58.5% were men. By the end of the follow-up period (December 2008), 1,225 patients had died and 68.4% of deaths were due to colorectal cancer. The 5- and 10-year cancer-specific survival rates were 55.5% (95%CI 53.9-57.9%) and 48.5% (95%CI 45.6-51.3%), respectively. The 5-year specific survival rate improved in the last period (2003-2007) (60.4%, 95%CI 55.4-65.0) compared with 1992-1997 (53.4%; 95%CI 49.2-57.4) and 1998-2002(52.0%; 95%CI 47.8-56.2). Various factors were independently associated with excess CRC mortality: male sex (HR 1.21), age at diagnosis > 75 years (HR 1.97), rectal location (HR 1.33), more advanced stages (stage IV: HR 18.54), poorly differentiated/undifferentiated tumors (HR 1.80), and admission through the emergency department (HR 1.52). Conclusions: cancer-specific survival improved from 1992 to 2007. This improvement could be due to more effective treatment, since changes in stage distribution or age at diagnosis were not observed during the study period. Overall survival rates should notably improve with the implementation of a population-based colorectal cancer screening program in Spain.