Topic of Cancer

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Cancer is the world’s leading cause of premature death.

That being said, let’s cut to the chase: the public is under the impression cancer is routinely cured by evidence-based medicine (aka mainstream, occidental medicine). Is this really the case?

First of all, what does it mean, to cure cancer?

For most of us, it would mean to be free of cancer cells in the body, without any symptom associated to their existence, and stay this way indefinitely, until death occurs from unrelated causes. In reality, current cancer treatments are more about attempting to increase survival together with maintaining quality of life, when compared to patients receiving other drugs. This means that a good treatment for cancer is able to make us get through a few more months than another drug already in use, ideally without taking what’s left of fun out of them.

Big money has been invested and big pharma has delivered a certain number of drugs – chemotherapy – as well as other cancer-breaking strategies (mostly through radiation). The number of FDA-approved anti-cancer drugs went from 69 (between 1965 and 2000) to 153 in 2015 (source Sloan Kettering). These drugs, associated to the improvements in overall diagnosis and patient care, are quite effective in terms of survival – treated cancer patients tend to live longer. There has been an average of 1.6% decrease in cancer death rate in the US between 2002 and 2011 (source). This has to be put into perspective with the astounding 40% of the worldwide population concerned with cancer at some point during their lifetime (source).

Many of these therapies have been used long enough to notice there are not only acute side-effects (the well-known vomiting-diarrhea-hair loss picture we all have in mind) but also long term effects: more cancer. Bitter sweet irony! The world invests colossal sums of money in cancer research, the industry develops the cures which we pay again in order to benefit from them, we go through hell and back, hopefully don’t die in the process, get on with life, only to get vacuumed once more in this death trap because of a new cancer, this time related to the cure of the first one….

The strange life of surrogates

Needless to say – this didn’t look good, so scientists went back to the bench and tried to find something that could predict which patients would most benefit from a particular treatment in order to target them specifically. This is how the search for predictive markers began. We nowadays have a wide variety of them, spanning from easy ones like metastases in lymph nodes to the sophisticated search of specific mutations in the genome of a specific tumor, inside a specific patient (overview here).

Predictably, things got even more complicated: some very accurate predictive markers proved to be difficult to work with. For instance, in order to measure them, one would need to inflict a risky procedure to the patient. So this is how we began searching for surrogate markers of predictability. This is one of the reasons why medical imaging (such as CT scans, MRIs, PET scans) has tremendously developed over recent years.

The compass is broken

There has been a shift in our collective reasoning. Somewhere along the road, we found it is time- and resource-consuming to directly measure the number of days a particular cancer treatment adds to a patient’s life. There are now surrogate markers of survival and of life quality – such as Progression Free Survival. You need to know about this one, for this is what doctors hear about on a daily basis from the industry.

“Progression Free Survival (PFS) rate is the number of people who still have cancer, but their disease isn’t progressing. This includes people who may have had some success with treatment, but the cancer hasn’t disappeared completely” (Source: Mayo Clinic). This might seem a good surrogate marker for survival – if only a high PFS rate were actually linked to a better rate of survival….but it’s not. Why? it is hard to explain since scientists don’t fully understand it. Nevertheless, the shift has been operated and PFS has become the main “end-point” in most clinical trials. New treatments are developed to slow down cancer progression whether this translates into a longer and better survival or not.

One more thing: all these rates are calculated on a 5-year basis. This does not mean that cancer cannot occur afterwards. It is an agreement between medical and industrial worlds to use the 5-year deadline in studies, for it is less expensive to use in trials.

One can only respect and encourage the efforts of the ones engaged in this mind-boggling work. Nevertheless, these people might have lost track of the essential point at the heart of their work. Slowly, we see a shift in the way cancer is measured and referred to  – lowering expectations from new anti-cancer drugs in the process. A fairly good drug today, is a drug capable of improving PFS by, let’s say, 4 months, regardless of its effect on actual survival or quality of life (example here). And this drug will soon become part of international guidelines for cancer treatment, which means that oncologists all over the world will be bound to prescribe it to their patients.

In 2009, two brave oncologists published an article that called medical community to embrace an ethical approach and challenge the validity of official guidelines regarding cancer drugs with limited benefits.

If we allow a survival advantage of 1.2 months to be worth $80 000,
and by extrapolation survival of 1 year to be valued at $800 000, we would need $440 billion annually — an amount nearly 100 times the budget of the National Cancer Institute — to extend by 1 year the life of the 550 000 Americans who die of cancer annually. And no one would be cured.

Yes, you’ve read it right: And no one would be cured.
 

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