WE read with great interest the article “A case for immunotherapy” (Sunday Star, Feb 12). Firstly, we would like to congratulate Chin (nasopharyngeal cancer) and Wong (prostate cancer) on improvements in their condition and for their successful struggle against cancer. Many like these two men are increasingly facing up to the reality of a cancer diagnosis as its prevalence rises in the Asia-Pacific region. However, upon reading the article we also noted several disturbing points regarding their treatment which we would like to highlight here.
Firstly, immunotherapy is indeed emerging as a new and exciting breakthrough in our treatment armamentarium against cancer. Immunotherapy aims to harness or enhance the ability of our own immune system to recognise and mount an immune response against cancer cells. Indeed, over the past few years, several immune therapies such as PD-1 and PDL-1 checkpoint inhibitors have now received licensing approval from major health authorities such as the US Federal Drug Agency (FDA) and European Medicines Agency (EMA). Much time, cost and effort have gone into performing clinical trials involving thousands of patients in order to prove that these treatments are superior to current available treatments and can be safely given with acceptable side effects. Not least as these treatments are usually very costly, we need to be sure that they work before they are offered to the public.
In contrast, the HITV (Hasumi Immunotherapeutic Vaccine) treatment in combination with radiotherapy is not an FDA or EMA approved therapy. There are no large phase 2 or phase 3 clinical trials (such trials are a necessary requirement before new therapies can be approved by the regulatory authorities) that have been performed to prove that it works any better than conventional chemotherapy, radiotherapy or targeted therapy alone. Indeed, the clinical trials to explore whether cellular immunotherapy treatment such as HITV are effective are currently only in an initial stage of development and it is premature to suggest that these treatments should be offered widely to the public.
Regarding the specific cases discussed, it is already well known that radiotherapy alone can cure up to 80% of patients with stage 2 or 3 nasopharyngeal cancer. It is highly questionable whether HITV immunotherapy would have provided any additional benefit on top of highly effective treatment with radiotherapy.
In the case where prostate cancer had spread to the pelvic bone (which incidentally would make the patient stage 4 cancer, not stage 3 as reported), the article omitted to report whether the patient was receiving hormonal therapy. We would be very surprised if the patient was not receiving hormonal therapy as it is the standard treatment for stage 4 prostate cancer and is over 90% effective in controlling this disease. Coupled to radiotherapy, which confers further benefit, this makes this combination approach extremely effective for the vast majority of prostate cancer patients. Again, it would be questionable whether HITV treatment would have provided any additional benefit to this patient.
As health professionals, we fully empathise with the dilemma and plight of cancer patients who are beginning their struggle with cancer. In the midst of the shock of receiving the news of the diagnosis, frequently they will also receive conflicting advice from well-meaning friends and relatives.
Often times, patients would recoil at the mention of the word “chemotherapy” and do everything in their power to find alternative solutions. This well-meant advice, however, may not necessarily be beneficial nor accurate.
We would caution patients to consider whether any proposed treatment is backed up by proof. Claims that a particular therapy, be it immunotherapy or alternative therapy, which may act as an “adjunct” to conventional therapy must be substantiated by proof. Claims that a particular treatment is effective due to the existence of limited laboratory data is inadequate to bring it into clinical practice that requires scientific rigour.
Claims, no matter how plausible, for example the use of radiotherapy or chemotherapy to release tumour antigens to sensitise dendritic cells, must ultimately be backed by proof, which MUST come in the form of phase 3 clinical trials whereby one group of patients is exposed to the treatment and one group is not, and the former group must record an improvement in survival and/or quality of life.
Some therapies claim proof in the form of a handful of anecdotal patients who have benefited, which is insufficient and subject to bias from the person offering the therapy. Claims that a particular treatment is preferable because of minimal side-effects over conventional therapy is insufficient to justify it being recommended for use. Furthermore, many of these non-conventional immunotherapy and supplemental therapy are very costly.
Increasingly, oncologists are witnessing patients who are suffering from financial burden due to their expenditure on cancer care. We have encountered many patients who have expressed regret having spent large sums of money over ineffective cancer treatments only to be left without resources for subsequent effective therapy.
There is a huge industry revolving around the sale of non-licensed “adjunct” medical therapies or supplements and we would like to remind patients that these are fundamentally commercial entities. We strongly advise patients to be judicious when choosing the appropriate therapy for their illness and to consult an oncologist accredited in their respective national specialty register.
The good news is that as cancer therapies are becoming increasingly sophisticated, our results are improving in great strides and the side-effects are reducing significantly. The guiding principle behind modern oncology care is to prolong life while maintaining good quality of life.
In view of this, we hope patients will continue to seek professional help from their local accredited oncologist. If in doubt over a particular therapy, we simply advise patients to demand phase 3 clinical trial proof that the treatment works. Otherwise, you may just be buying hope and a feel-good placebo effect.
MALAYSIAN ONCOLOGICAL SOCIETY
In conjunction with Dr Ravindran Kanesvaran
President, Singapore Society of Oncology