Over the last couple of years, I’ve noticed an increased number of media reports about the new “cure” for cancer – immunotherapy. In the media, immunotherapy is portrayed as the new remedy for cancer, a wonder treatment designed to stop cancer in its tracks.
Not a week goes by when I’m not asked about immunotherapy by one or more of my patients, who are often unaware of where, in the big scheme of things, this treatment plays a role.
While I appreciate the need for public awareness of new treatments available, the information provided needs to be accurate. Time and time again, overstatements are made about what new treatments are capable of doing. I will never forget a speech delivered by Richard Nixon, when he was US President, in which he stated that by the year 2000 cancer would no longer be a major health issue. Well, here we are in 2017 and cancer is a major issue and, just as the case was back then, it’s not going to go away with one magic “cure”.
Cancer is a complex disease.
But let’s get into the details of immunotherapy or immuno-oncology – what it means, where it fits in the treatment of cancer and what can reasonably be expected from it now and in the future.
The concept behind immuno-oncology evolves around the biological principle which states that, ideally, when a cancerous cell develops in our body, the immune system will recognise it as abnormal and clear it from the body.
That is actually often the case and there will be no further problem with the occasional cell like that. The major problem appears to be when, for whatever reason, our immune system doesn’t recognise the diseased cell and allows it to replicate and multiply.
In the classical treatment of the cancer, we utilise surgery to remove the tumour, radiotherapy to irradiate and damage it and chemotherapy and targeted therapies to destroy it. All of these treatments have a role to play in any particular cancer, either as a single modality or in combinations.
Recently it was suggested that, if we could stimulate our own immunity to fight and destroy the cancer, we could add another modality to this range of treatments. The real trick is to not only stimulate the immune system (which by itself is not helpful), but unmask the cancer to be recognised by our immunity.
Indeed, research and development of this idea over the last decade has resulted in major improvements in the treatment of some cancers, with unprecedented results causing a media frenzy. A prime example where immunotherapy has made major in-roads is in the treatment of melanoma where, in the disseminated stage, the median life expectancy
without or even with best available treatment was around six to 12 months. Since the advent of immunotherapy, we are seeing patients surviving up to five years – even more in some cases.
That is an excellent news, however – as is always the case in cancer medicine – we have to look at it from a broader perspective. We need to consider a number of basic biological principles, which still apply in oncology.
Firstly, no matter what treatment is presently available, the cancer will ultimately develop a resistance to it, just like bacteria become resistant to antibiotics.
Secondly, no matter which treatment we employ, all have side effects. The side effects of immunotherapy may be potentially life-threatening – the drugs we administer may simply activate our immunity to turn against our own organs in the form of an autoimmune disease like rheumatoid arthritis or systemic lupus. The immunotherapy may cause our own immune system to destroy whole organs in this way. We can, of course, detect this process quickly and avert any major problems, however it often means the treatment can not be continued.
The third problem with immunotherapy is that it simply does not work in all cancers. At present, there are major advances and activity in melanoma, lung cancer and some lymphomas. In certain cancers, though, the strategy simply does not deliver any good results.
The fourth fact to consider is that immunotherapy sometimes works best with other methods of treatments, such as modern chemotherapy or radiotherapy, so it is not by itself the answer to all.
Some of the points above are just the tip of the iceberg regarding the complexity of modern cancer treatments and will, hopefully, highlight the issues we must consider every time we design and administer treatment for cancer.
There are now number of immunotherapy agents available in Australia which are designed for a number of specific malignancies. Some of the agents are now covered by the PBS (Pharmaceutical Benefits Scheme) and free for patients who qualify for the use of that particular agent. There are also options available which can be funded by health funds or patients themselves.
The issue to consider, however, is that the potential cost can be substantial and the benefit minimal, especially if the treatment is given for a condition not proven to respond favourably. There are treatments which can be far more efficient and less costly.
In oncology, as in life, the rule applies that the newest thing may not always be the best. There is another golden rule – it takes time to master the knowledge and understanding of any new drug used in medicine. It always takes a long time for all unknown, long-term effects to present themselves.
There is no doubt that immunotherapy is here to stay and will bring major benefits to our cancer patients. As with all other treatments, it will take some time to understand this method of treatment and be able to determine exactly where it belongs in order to maximise the benefits.
Immuno-oncology is an exciting, new and promising approach and will most certainly take the fight against cancer to new level. Cancer is becoming a chronic disease, not unlike diabetes or chronic heart disease, where patients are living longer and better despite their disease. It will just need ongoing management and care.
