Comparison of 5-day, 1-day, and 2-day cyclical combination chemotherapy in advanced breast cancer.

The results of 5-day cyclical combined chemotherapy for advanced breast cancer were compared in two trials with the less demanding 1-day and 2-day regimens. At all stages, except at 3 months, 5-day treatment was significantly more successful in providing regression and remission of tumours than the 1-day regimen. However, although the differences are not statistically significant, data from the second trial indicated that the 2-day regimen tended to be more effective than the 5-day regimen. The lower 95% confidence limit for the success of the 2-day treatment was 56.2% at 3 months.