The emperor’s new clothes – can chemotherapy survive?
Eva Segelov, Medical Oncologist, St Vincent’s Clinical School, Sydney
(Aust Prescr 2006;29:2-3)
‘An Australian study suggests that the benefits of chemotherapy have been oversold … Why has it been oversold? Are you suggesting that medical oncologists in Australia are just sort of marketing shysters or what?’ These were some of the questions posed by Dr Norman Swan when he presented the Health Report on ABC Radio National on 18 April 2005. Dr Swan was quizzing Associate Professor Graeme Morgan, the lead author of a controversial article entitled ‘The contribution of cytotoxic chemotherapy to 5-year survival in adult malignancies’. This article reported that chemotherapy has improved survival by less than 3% in adults with cancer.
These provocative figures were derived from a literature search of all randomised clinical trials reporting a five-year survival benefit attributable solely to cytotoxic chemotherapy in 22 major adult malignancies. The common malignancies of bowel, lung, breast and prostate were included. The total number of newly diagnosed cancer patients for each malignancy in 1998 was determined from cancer registry data in Australia and the USA. The absolute number to benefit was the product of the total number of patients with that malignancy, the proportion or sub-group(s) with that malignancy showing a benefit, and the percentage increase in five-year survival due solely to cytotoxic chemotherapy. The overall contribution was the sum total of the absolute numbers of patients showing a five-year survival benefit expressed as a percentage of the total number for the 22 malignancies.
Overall cancer survival, following all kinds of treatment, is approximately 63%. Based on the calculations in the study the contribution of chemotherapy to adult survival from cancer was estimated to be 2.3% in Australia and 2.1% in the USA. The authors, two of whom are radiation oncologists, but one of whom is a practicing professor of medical oncology, concluded that ‘chemotherapy only makes a minor contribution to cancer survival’ and ‘to justify the continued funding and availability of drugs used in cytotoxic chemotherapy, a rigorous evaluation of the cost-effectiveness and impact on quality of life is urgently required’.