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

It has been demonstrated that adjuvant chemotherapy in TNM stage III and palliative chemotherapy are effective treatments for colon cancer.

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.

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.

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.

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.