Cancer is a leading cause of death worldwide. Major advances in cancer chemotherapy have been achieved over the years, increasing the cure rate as well as the average survival rate of cancer patients. While more effective treatments are available, conventional chemotherapy nevertheless suffers the drawback of significant associated toxicity. The problem arises from the relatively non-specific mechanism of action of most chemotherapy leading to damage of not only cancer cells, but also of normal cells of the body. More potent combinations of chemotherapy therefore often carry with them more severe side effects. In the quest for better treatment, specific therapy that targets the cancer cells and boosts efficacy while minimising the “collateral damage” to normal cells of the body, remains the holy grail of anti-cancer treatment strategy.
Over the last few years, targeted therapy has become a reality.
In the field of early breast cancer treatment, the use of the antibody Herceptin® in patients with tumours displaying the target has led to a dramatic decrease in relapse rate not seen in several decades.
Apart from antibodies, a class of special molecules has been developed to block specific targets on cancer cell responsible for cancer growth. Members of this class of drugs, Iressa® and Tarceva® have entered clinical use and have found applications in the treatment of advanced cancer of the lung and pancreas. Their favourable side effect profile and ease of oral administration are especially attractive. These drugs have made available a treatment option for patients who are either unable to receive chemotherapy or who suffer from tumours that are not responsive to chemotherapy.
These improvements give us cause for optimism in our relentless pursuit of better cancer treatment.