Professor Annie Joubert from the University of Pretoria.
Cancer is often preventable, so creating awareness and highlighting possible risk factors is crucial
As the world observes World Cancer Day on 4 February, the prevalence of cancer is increasing worldwide, emphasising the demand to globally intensify cancer awareness and alert people to strategies that address the burden of this disease. According to the World Health Organization, cancer led to approximately 10 million deaths in 2020 globally, with an estimated 18.1 million new cancer cases reported. The Cancer Association of South Africa reported that breast cancer in women and prostate cancer in men are among the top five cancers prevalent in South Africa. The lifetime risk of South African women being diagnosed with breast cancer is one in 27. The National Cancer Registry reported in 2019 that the lifetime risk for prostate cancer in men is one in 15 in South Africa. However, according to the World Health Organization, between 30% and 50% of all cancer cases are preventable. Thus, creating awareness and highlighting possible risk factors are crucial to address the burden of this disease.
World Cancer Day was conceptualised in Paris at the World Summit Against Cancer for the New Millennium in the year 2000. The objectives of the summit were to raise cancer awareness, promote cancer research, advance patient care and prevent cancer.
This year we commemorate World Cancer Day with the theme Close the Care Gap. Considerable progress in cancer cell biology has paved the way for advanced technology for early cancer detection, screening and surveillance in modern oncology. In 1953 the DNA structure discovered by Francis Crick, James Watson, Maurice Wilkins and Rosalind Franklin was published in Nature. The international Human Genome Project took 13 years to finalise and was declared complete on 14 April 2003. Humans have between 20 000 and 25 000 genes. Cancer is ultimately a disease of DNA — mutations in the genome influence the risk of being diagnosed with it.
Cancer and hereditary factors
If cancer is common in a family, the possibility exists that mutations are being passed from one generation to the next. Genetic predisposition to cancer doesn’t necessarily indicate that a person with such a mutation will be diagnosed with cancer; only 5% to 10% of all cancers can be attributed to genetic inheritance. Gene mutations may occur for several other reasons, namely gene mutations inherited from parents or gene mutations that occur after birth. These mutations may be triggered by risk factors such as tobacco products, alcohol consumption, diet, environmental pollutants, ultraviolet radiation, reproductive and hormonal factors, occupational exposures and infection-attributable cancers.
Traditional cancer treatment options include surgery, chemotherapy and radiation. Stem cell transplants are based on restoring blood-forming stem cells in cancer patients when their blood-forming stem cells have been destroyed due to high doses of chemotherapeutic drugs or radiation therapy. The advent of modern DNA technologies, and particularly next-generation sequencing, is rapidly changing the face of this illness, diagnostics and treatment. The possibility of screening for DNA mutations in genes that may increase the risk of cancer is advancing with the production of panel testing kits, some of which can target hundreds of genes. The genomic picture can be used to assess a patient’s cancer risk and progression, and to design tailor-made treatment strategies. There is no doubt that the development and roll-out of these tests will save lives.
Cancer treatment approaches may also include personal oncogenomics, immune-modulating drugs, antibodies targeting and destroying the cancer cell per se, hormone therapy, epigenetic drugs that regulate genes causing cancer, vaccines, cell cycle checkpoint inhibitors and cell-based therapy.
For individuals, access to advanced testing is typically through a cancer centre or an oncologist, who will arrange for a pathology company or specialised DNA analysis company to analyse samples, followed by subsequent consultations with an oncologist and a genetic counsellor. As with most cutting-edge technologies, many of the new testing approaches are costly, not yet commonly available, have not yet been approved for clinical use in all countries, are not part of health insurers’ benefits and are sometimes available only to patients that are included in large research trials. Still, the rapid development and roll-out of these tests are starting to save lives.
Cancer can be beaten
Advances in genomic research reveal the biology of disease and ultimately contribute to redefining our health management today and in the future. On World Cancer Day we also recognise scientific accomplishments and acknowledge that the vast amount of knowledge available today will lead to tomorrow’s discoveries that will ultimately contribute to our health and wellbeing, especially in the fight against cancer.
There are millions of cancer survivors worldwide, again emphasising the importance of cancer awareness, early detection and treatment. Let us together ‘close the care gap’ in cancer care. Everyone can contribute towards cancer mindfulness to overcome barriers to early detection, cancer treatment and palliative care.
For each of us that starts promoting cancer mindfulness, there is increased hope — “Awareness today, a cure tomorrow!”
Professor Annie Joubert is Head of the Department of Physiology at the University of Pretoria. Her research focus is cancer cellular physiology. She studies cancer drug design and cancer cell signalling to identify targets for therapeutic intervention in the fight against cancer.