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We Will Never Cure Cancer, So Should We Even Try?

Credit: dcleomiu/Adobe

Credit: dcleomiu/Adobe

By Nial Wheate

Billions of dollars are spent on cancer research each year for minimal gains. Would that money be better invested elsewhere?

In 2014, cancer overtook cardiovascular disease as the leading cause of death in the world. While the incidence of cancer has continued to rise, the long-term survival rate has increased from 47% during the mid-1980s to more than 65% by 2010.

Despite this promising improvement in survival, the unique nature of the disease means it is unlikely that it will ever be declared cured. This is because there will never be a single drug that is capable of curing all forms of cancer, and the success of treatment is highly dependent on how early it is detected.

Instead, better screening techniques and the use of personalised medicine will improve the success of treatment in the coming decade, but it will never reach 100%. And even if we could cure cancer, the financial cost may be too high, especially when the money to do so could be better spent elsewhere.

In 1906 the German scientist, Paul Ehrlich, coined the term “magic bullet” to describe a single drug that could specifically seek out and kill a disease with little or no side-effects.

The magic bullet theory certainly holds true for many types of disease. Take bacterial infections as an example. When the antibiotic penicillin was discovered, it literally was a magic bullet that saved many millions of lives.

But the important thing with antibiotics, if we discount the rising problem of resistance, is that there is no variability in response between different patients. If a treatment works in one patient with a particular infection we know that it will work in another patient with the same infection. This, however, is not the case for cancer.

The biggest obstacle to curing cancer is that it is not a single disease but a family of more than 100 different diseases, all of which require different treatments. Traditionally doctors have classified cancer into groups based on the part of the body in which it is first found: breast, lung, testicular, bladder. But when we treat what we think are the same types of cancer we find that they can respond in completely different ways.

What this means is that even if a breakthrough is made for one type of cancer, its benefit is unlikely to transfer to other types of cancers. To properly cure cancer, many hundreds of different drugs will still need to be developed, each treating only a small range of cancers.

The second important factor is that doctors don’t ever declare a patient as being cured because it’s too difficult to know whether there are still microscopic pockets of cancer that didn’t get picked up during treatment. In these cases, patients can relapse months or years later. Instead of using terms like “cured”, doctors often refer to one- and five-year survival rates.

So if we aren’t ever going to find a single drug that will cure cancer, what does the future hold?

The coming decade will herald the age of personalised medicine. Instead of classifying cancers based on the region of the body in which they are found, we are now looking at cancers at the molecular level and reclassifying them based on the particular markers we find on, or inside, the cancer cells.

For instance, there are three different markers for breast cancer: the oestrogen receptor (ER), the progesterone receptor (PR) and the HER2 receptor. After testing for these, each patient is classified as having a normal (negative) or excessive (positive) amount of each receptor. For example, one patient may be classified as ER+, PR+ and HER– while another patient may be ER–, PR– and HER+. In total, the combination of the three different receptor levels gives rise to six different types of breast cancer, and each needs a different cocktail of drugs.

Unfortunately, while personalised treatments tends to be much more effective, with patients enjoying better survival rates, it’s a major problem from a government or pharmaceutical companies’ economic perspective.

It is very expensive to develop, test and get approval for a new drug. Depending on who you ask, the cost of taking a drug from discovery to the market is $1–5 billion. This makes research into new drugs a risky venture that is only offset by many years of patent-protected sales.

To be really profitable a new drug must have global sales of more than $1 billion per year, but to achieve this status a drug needs a very large patient base to whom it can be sold.

As treatments become more personalised, the number of patients treated with a particular drug will drop remarkably. This means there simply won’t be a sufficiently large patient base in the future to justify new drug development. The result may be that pharmaceutical companies won’t bother exploring new drugs for personalised cancer treatment, or that they will be forced to sell the drugs at exorbitant prices.

As the average patient can’t afford the price of chemotherapy drugs, the cost is pushed onto health insurance companies. Alternatively, the cost is covered by the government, which subsidises the medicines by up to 99%. Either way, new drug development leads to unsustainable health insurance premiums or government health care costs.

This raises the question: should we even be looking for a cure for cancer?

An important fact to note is that the majority of new drugs that are approved do not greatly increase life expectancy. On average they only ever give the patients a few months longer to live compared with the drugs we already have available. Given this, can we justify meeting their high costs?

Last year the National Health and Medical Research Council, which funds the majority of medical research in Australia, spent $182 million on cancer research, mostly on the development and testing of new treatments. Likewise, Australia’s largest cancer charity, Cancer Council Australia, spent $1.6 million on cancer research funding. More than 100 other cancer charities in Australia spent many millions more on cancer drug discovery research and clinical trials.

Even bigger sums of money are spent in other countries. The National Cancer Institute in the USA has a budget of just under $5 billion for the current financial year, and Cancer Research UK spent £460 million (A$1.2 billion).

While not all the money spent on cancer research is for the discovery of new treatments, we have to ask ourselves, as a society, whether just a fraction of this money could provide much more substantial benefits if it was redirected? How many teachers, police, firefighters or social workers could this money be used to employ? What environmental projects won’t be funded because of our continued investment in cancer drug research? How many children could be lifted from poverty and given education and opportunities they would not otherwise get?

Even if the money was kept for cancer research, it could be better spent on awareness programs, better and earlier detection methods, research programs to gain a deeper understanding of its causes, or to build more specialised cancer treatment centres so that patients get the level of care they need.

In the following decade the burden of cancer as a disease in society will continue to increase because of the ageing population. With the cost of drugs continuing to rise and the fact that there will never be a single treatment that will cure all cancers, we need to either find a way to reduce costs or redirect the money that would be spent on treatment research to other areas where it will provide the most benefit.

Nial Wheate is a Senior Lecturer in the Faculty of Pharmacy at The University of Sydney.