There are, broadly speaking, four ways to fight cancer. You can cut a tumour out, with surgery. Or you can try one of three different ways of killing it. Radiotherapy targets tumours with radiation. Chemotherapy uses chemicals that poison all rapidly dividing cells, cancerous ones included. “Targeted therapies”, as their name suggests, recognise particular features specific to cancer cells.
Singly and in combination, these four types of treatment have contributed to a steady increase in the survival rates for most kinds of cancer. Now they may be joined by a fifth. At this year’s meeting of the American Society of Clinical Oncology (ASCO), in Chicago, the assembled researchers heard about the latest progress in “immuno-oncology”.
Modern medicine provides every reason to think that the immune system””which, after all, is there to keep the rest of the body safe””can and does attack cancers. People whose immune systems have been weakened, either by disease or by medicines designed to help them tolerate organ transplants, run a greater risk of malignancies. Many risk factors for cancer, such as a bad diet, heavy drinking, stress and smoking are known also to affect the immune system. Exercise, thanks to the boost it gives the body’s defences, can improve cancer survival rates.