The contribution of cytotoxic chemo to 5-year survival in adult malignancies
The debate on the funding and availability of cytotoxic drugs raises questions about the contribution of curative or adjuvant cytotoxic chemo to survival in adult cancer patients.
Materials and methods
We undertook a literature search for randomised clinical trials reporting a 5-year survival benefit attributable solely to cytotoxic chemo in adult malignancies. The total number of newly diagnosed cancer patients for 22 major adult malignancies was determined from cancer registry data in Australia and from the Surveillance Epidemiology and End Results data in the USA for 1998. For each malignancy, the absolute number to benefit was the product of (a) the total number of persons with that malignancy; (b) the proportion or subgroup(s) of that malignancy showing a benefit; and (c) the percentage increase in 5-year survival due solely to cytotoxic chemo . The overall contribution was the sum total of the absolute numbers showing a 5-year survival benefit expressed as a percentage of the total number for the 22 malignancies.
The overall contribution of curative and adjuvant cytotoxic chemo to 5-year survival in adults was estimated to be 2.3% in Australia and 2.1% in the USA.
As the 5-year relative survival rate for cancer in Australia is now over 60%, it is clear that cytotoxic chemo only makes a minor contribution to cancer survival. To justify the continued funding and availability of drugs used in cytotoxic chemo , a rigorous evaluation of the cost-effectiveness and impact on quality of life is urgently required.