Chemotherapy for colon cancer in a well-defined French population: Is it under- or over-prescribed?

Abstract

Background: It has been demonstrated that adjuvant chemotherapy in TNM stage III and palliative chemotherapy are effective treatments for colon cancer. Aim: To determine changes over a 10-year period in the practice of adjuvant and palliative chemotherapy for colon cancer in a well-defined French population. Methods: Some 4093 patients with colon adenocarcinoma diagnosed between 1989 and 1998 were studied. To estimate the independent effect of the studied variables, a non-conditional logistical regression was performed. Results: The proportion of patients with stage II disease treated with adjuvant chemotherapy increased from 2.3% (1989-90) to 20.5% (1997-98). The corresponding figures for stage III patients were 7.1% and 54.9%. This increase was particularly marked in younger patients, with 47.3% of stage II and 86.1% of stage III patients under the age of 65 years being treated in the 1997-98 period, compared with 4.9% and 24.4% of those over 75 years for the same period (P < 0.0001). The use of palliative chemotherapy increased over time from 13.6% (1989-90) to 38.9% (1997-98). Again, this increase was more dramatic in the younger age group. Conclusions: The use of adjuvant chemotherapy has increased for stage II disease despite the absence of proven effectiveness. Both adjuvant and palliative chemotherapy are still under-prescribed in patients over the age of 75 years.