Malaysia has the highest mortality rate for breast cancer in the Southeast Asian region, according to the World Health Organization Global Cancer Observatory (WHO GLOBOCAN) 2012.
This is most likely due to late detection and the preference for alternative therapy over medical therapy. About 50 per cent of breast cancer patients in Malaysia still present at the advanced Stages of 3 and 4 (Malaysian National Cancer Registry 2017-2021). even though breast cancer is one of the cancers which is the easiest to detect at an early stage.
Similar grim statistics are seen for all the other common cancers in both Malaysian men and women, such as lung cancer, colorectal cancer, prostate cancer, uterine cervix cancer, and nasopharyngeal cancer. Malaysian patients may be apprehensive to start their treatment due to the misinformation and myths associated with cancer treatment.
Conventional cancer treatment, such as chemotherapy, has side effects due to its effects on normal cells in the body. Due to this, researchers around the world have endeavoured to come up with methods to optimise and personalise cancer treatment.
One such method is precision medicine. Precision medicine uses next generation sequencing (NGS) to determine the genetics of cancer cells and from there, cancer treatments can be personalised with greater precision.
Using Genetics To Fight Cancer
NGS provides oncologists with a clearer picture on the causative mutations. Depending on the cancer, numerous genetic mutations have been identified and specific treatments have been designed to combat these mutations.
For example, targeted therapy and immunotherapy options have been designed based on the genetic mutations found in breast and lung cancers.
Cancer treatment is determined by the diagnosis and results obtained from the biopsy. With precision medicine, biopsies are taken from the tumour(s) and blood, known as solid mass and liquid biopsy, respectively. NGS should be done at diagnosis as the results obtained will help determine the best course of treatment for the patient.
This is similar to antibiotic treatment in bacterial infections which is personalised based on the causative microorganism. Cancer treatment should be personalised as well based on the patient’s cancer mutation information obtained through NGS.
Solid mass biopsies are typically done for clinical diagnosis of cancer. However, while less common,
liquid biopsies are less invasive and are an alternative when solid mass biopsies are not feasible. Liquid biopsies are done by analysing the patient’s blood for cancer circulating tumour DNA (ctDNA). ctDNA circulate in the blood when cells break off from the tumour and travel through the bloodstream.
A liquid biopsy can pick up the ctDNA to determine the cancer genetic mutations. There are limitations to liquid biopsies as the quantity of ctDNA may be small.
Due to this, solid mass biopsies may still be required. Liquid and solid mass biopsies should be used appropriately to provide a clearer picture of the genetic mutations in the cancer cells.
Personalised Treatment For Cancer
Targeted therapy is a new form of cancer treatment that utilises molecular compounds, which bind specifically to targets on a cancer cell to destroy it. There are numerous options of targeted therapy based on the genetic mutations of cancer cells.
For example, breast cancer patients with the HER2 mutation have options like pertuzumab and trastuzumab. Lung cancer patients with the EGFR mutation can consider gefitinib, erlotinib, or osimertinib targeted therapy. Targeted therapy generally has fewer side effects, gives patients better quality of life and better survivability.
Another new form of treatment is immunotherapy, which is the latest paradigm in cancer treatment. Immunotherapy helps the body harness the pre-existing immune defences to recognise and attack the cancer cells.
For example, pembrolizumab, an anti-PD-1 immunotherapy, removes the break put on by the cancer cells on the T-cells of the immune system through the PD-1/PD-L1 pathway (Figure 4). This allows the T-cells to recognise the cancer cells and destroy them.
Immunotherapy has revolutionised cancer treatment and has become the new standard of care for many types of very aggressive and resistant cancers like advanced lung cancer, kidney cancer, liver cancer, and malignant melanoma (a type of skin cancer).
Cancer Is Common
Cancer is common in Malaysia and worldwide. Approximately one in every four Malaysians will be diagnosed with cancer in their lifetime. This could be due to a variety of reasons, including an unhealthy lifestyle.
Alarmingly, data from international organisations like the WHO GLOBOCAN predict that cancer incidence will get higher in the future and more younger patients will be affected.
In dealing with this national and global public health problem, it is not just prevention is better than cure, but early detection through screening and effective treatment are the keys to saving more lives. When cancer is detected early, it can be cured and the treatment is less costly and complicated.
Even in advanced cancer, there is hope with the advent of new therapies like targeted therapy and immunotherapy. These drugs, alone or in combination with chemotherapy, provide better survival rates while helping patients maintain quality of life.
Precision medicine is the future in oncology to optimise and personalise cancer treatment.
Dr Aminudin Rahman Mohd Mydin is a consultant clinical and radiation oncologist at KPJ Damansara Specialist Hospital. He is also a Clinical Associate Professor at the Graduate School of Medicine, KPJ Healthcare University (KPJU), and an Executive Council member of War-on-Cancer Malaysia (WonC), an initiative by the College of Physicians, Academy of Medicine Malaysia to prevent, overcome and eliminate cancer in Malaysia.
- This is the personal opinion of the writer or publication and does not necessarily represent the views of CodeBlue.
