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There are more positive voices in cancer research, and there are undoubtedly interesting and important developments in the pipeline; but the shift in emphasis called for in the review (above) has still not occurred. Profit is what appears to drive much of the world, and there is no great profit to be made in cancer prevention. The drug companies still make their money from magic bullets designed to kill cancer cells; but in the area of cancer, where the enemy cells are so very like the host, the risks of collateral damage are very high indeed.
During the ’70s and ’80s a drug company had to submit two favourable, large randomised trials to obtain US Food and Drug Administration (FDA) approval for a new drug. "Favourable" meant that there must be a certain rate of tumour shrinkage lasting for at least one month. It was not necessary to show that the treatment prolonged survival, and it was not necessary to submit the results of any unfavourable results from the same drug.
These guidelines, already less than stringent, were relaxed further in the ’90s. Drug companies can now get FDA approval on the basis of small preliminary trials, even if a large randomised trial may subsequently give unfavourable results. In a remarkable statement about drug approvals, an FDA spokesperson pointed out that any delay in approval did not mean unnecessary deaths because "none of the treatments for advanced cancer cure people".
The truth is that cancer is at an all-time high. It is also very likely that in the near future we will see cancer figures rising yet further, fuelled in part by the staggering increases in overweight and obesity that are occurring all over the world. Because as we get fatter, we become more likely to develop a range of cancers (Bianchini et al ’02, Calle et al ’03, Freedland et al ’05).
The huge research effort into cancer has produced treatments which are less than rigorously screened, are non-curative, which may extend life in some cases – but are generally toxic, responsible for many adverse effects, are powerful carcinogens in their own right (Klein–Szanto ’92), and too often ineffective or even counter-productive (Chute et al ’97, Lassen et al ’98, PORT ’98, Rougier et al ’98, Bandealy et al ’98, Wolmark et al 2000, Riccardi et al 2000, Schulman et al ’03).
If this strikes you as a poor bargain, many cancer specialists would agree. 18 years ago, when 118 oncologists at a major cancer institute in the United States were asked whether they would opt for chemotherapy if they were diagnosed with non-small-cell lung cancer, three-quarters said they would turn down the treatment.
Why? "Ineffective and unacceptably poisonous." (Mackillop et al ’87)
The cancer concerned was (and is) a difficult one to treat – but hardly unique in that respect. And although the question has not been formally asked since, my own experience with oncologists leads me to believe that the majority of them would still not willingly accept chemotherapy for many cancers.
However, I do not want to be too pessimistic – it IS true that survival rates of people living with cancer are increasing. And the fact that death rates have not leapt up in parallel with incidence rates is testimony to the fact that there have been improvements in palliative therapy. However, the fact that the incidence rates have also risen so far in so short a period of time (effectively, within two generations) shows that we have failed to make any progress in terms of disease prevention.
But let’s start by looking at a significant success. |