Cancer is one of the leading causes of morbidity and mortality worldwide, with approximately 14 million new cases reported annually, according to the World Health Organisation. Treatments, however, haven't always kept up, but experts say immunotherapy offers a promising new development in cancer treatment.
According to Dr Daniel Vorobiof, a medical oncologist and director of the Sandton Oncology unit, there were always four traditional modalities of cancer treatments, namely surgery, radiation, chemotherapy and hormonal therapy. Now immunotherapy can be added to the group – a method that can be used to combat cancers like melanoma.
According to Prof Nir Peled, a pulmonologist and thoracic medical oncologist from Israel, what makes immunotherapy more attractive than other modalities is that it has shown better durable responses with fewer side effects.
How do immunotherapy drugs work?
“While other modalities target the tumour, immunotherapy targets the hosts,” Dr Vorobiof says. Other cancer treatments, such as chemotherapy or radiotherapy, aim to poison cancer cells, while immunotherapies are aimed at stimulating and boosting the body’s own immune response to destroy cancer cells.
Cancer cells are different to healthy cells because they express abnormal proteins (antigens) that can be detected by immune cells. Tumour cells can, however, go undetected by the immune system if they express low levels of antigens.
Immunotherapy drugs aim to help immune cells recognise cancer cells. There are several types of immunotherapy drugs.
Side effects of immunotherapy
The downside to immunology is that not all patients respond the same way. Dr Vorobiof emphasises that the side effects of immunology need to be noted and patients need to be made aware thereof.
Some side effects of immunology drugs include:
- Inflammation of the thyroid
- Skin eruptions
- Fever or chills
“Once doctors and patients are aware of these side effects, they can manage them as they surface,” Dr Vorobiof explains.
The future of immunotherapy in SA
Prof Peled adds that although we are currently waging a losing battle against cancer with eight million people dying annually from the disease, there has been a sense of hope in the last few years thanks to updated therapies such as immunotherapy.
The US Food and Drug Administration (FDA) has approved 15 immunotherapy drugs for cancer care since 2011. Only one of these drugs, Ipilimumab for stage-four melanoma, is currently available in South Africa.
The next chapter for immunotherapy in South Africa is about to begin. “The next wave of immune discovery will be to identify patients as good candidates for immunotherapy,” says Dr Vorobiof.