Chemo – proven or disproven?
Posted by Jonathan Chamberlain on April 7, 2014
Proof or Disproof?
It seems obvious that to call a treatment proven is the opposite of calling a treatment disproven – but the more we think about it the less obvious this may be.
Let’s take as our starting point a treatment that is effective 95-100%. I think we would all be happy to consider such a treatment proven – and this is the case in relation to chemo and penile/testicular cancers. Chemo has a very high success rate in this area. Similarly we would be happy to call a treatment that had 0-5% success effectively disproven. Again chemo as a treatment for pancreatic cancers would come into this category and again there would be little argument. So far so good.
But what do we do with treatments that are 50% successful? Well, I think most of us would consider this also proven. It works half the time. That’s pretty good.
So what about a treatment that was 25% successful? Is this also ‘proven’? Perhaps, but we’re beginning to stretch the definition of ‘proven’ to its limits. OK so what about 10-15% effectiveness? Would this be proven or disproven?
It is in this area that calling it proven or disproven really depends on other factors – mainly on the point of view of the person judging the success or failure of the treatment. What about a 5-10% success rate? Again, if you are gung ho in favour of the treatment you’ll call it proven and if you are gung ho against it you’ll call it disproven. So there is no objective barrier between what is proven and what is disproven. It really is a matter of interpretation.
The problem for chemo is that its effectiveness as a stand alone treatment is not good. It varies from cancer to cancer. Overall the general range of figures quoted is 5-15%. But the truth is one or two cancers have very good responses to cancer and virtually all the rest have a very poor response. But many people with cancers for which the effectiveness is known to be low to zero nevertheless receive chemotherapy. In these cases doctors must accept that they are using disproven treatments.
Often they do so alongside surgery as insurance. Sometimes they mix two or three together and experiment on the patient. Sometimes the reason they give the treatment is not to be curative but to ‘buy time’. However there is a great deal of dispute as to how much time is generally bought in this way. Some people undoubtedly do buy a few months but many others die earlier than they might otherwise be expected to. All in all it’s a mixed picture. Doctors believe they are buying time because chemotherapy often causes tumour shrinkage – but this shrinkage is almost always temporary and when the tumour grows again it does so at vastly increased speed. Chemotherapy makes tumours more aggressive.
So, for many cancers, calling chemo a proven treatment is really stretching the bounds of what words mean.
If your doctor is advising chemo do get the figures for likely effectiveness. Chemo is generally brutal. You don’t want to incur pain only to discover it is likely hastening you to your death. Sadly that is what happens to some chemo patients. I know because it happened to my wife.