Colon cancer in France: evidence for improvement in management and survival.

BACKGROUND Cancer registries recording all cases diagnosed in a well defined population represent the only way to assess real changes in the management of colon cancer at the population level. AIMS To determine trends over a 23 year period in treatment, stage at diagnosis, and prognosis of colon cancer in the Côte-d'Or region, France. PATIENTS A total of 3389 patients with colon cancer diagnosed between 1976 and 1998. METHODS Time trends in clinical presentation, surgical treatment, chemotherapy treatment, stage at diagnosis, postoperative mortality, and survival were studied. A non-conditional logistic regression was performed to obtain an odds ratio for each period adjusted for the other variables. To estimate the independent effect of the period on prognosis, a relative survival analysis was performed. RESULTS Between 1976 and 1991, the resection rate increased from 69.3% to 91.9% and then remained stable. This increase was particularly marked in the older age group (56.4% to 90.5%). The proportion of stage III patients treated with adjuvant chemotherapy rose from 4.1% for the 1989-1990 period to 45.7% for the 1997-1998 period. Over the 23 years of the study the proportion of stage I and II patients increased from 39.6% to 56.6%, associated with a corresponding decrease in the proportion of patients with advanced stages. Postoperative mortality decreased from 19.5% to 7.3%. This led to an improvement in five year relative survival (from 33.0% for the 1976-1979 period to 55.3% for the 1992-1995 period). CONCLUSIONS Advances in the management of colon cancer have resulted in improving the prognosis of this disease. However, progress is still possible, particularly in the older age group.