WHAT IS CANCER?
HAS CANCER ALWAYS BEEN AROUND?
There’s a type of medical archaeology, called palaeooncology, which searches through our historical records for signs of cancer. Possibly the earliest reference comes from the Ancient Egyptian physician Imhotep, who lived around 2600 BC. He wrote about “bulging masses on [the] breast”. Even further back, evidence of cancer has been found in the foot bone of an ancient human relative who lived in what is now South Africa, 1.7 million years ago. So cancer is not a modern disease. But there are times in our history when the disease is not mentioned in the records. It’s possible that in ages where populations were ravaged by war, plagues and other infections, death rates were so high that cancer, often an age-related disease, was scarce.
HOW DOES CANCER START?
Almost all the cells in our body need to divide: it’s how we grow, and how we repair damaged tissue and worn-out cells. To do this, the cell’s DNA makes a copy of itself, and mistakes can happen in this process. These ‘mutations’ are common, and our body can repair them. But rarely, the mutations take place in a part of the DNA that controls cell division, and the cells don’t stop dividing. These cancer cells can eventually form a tumour, and the cancer can spread to other parts of our body.
CAN WE BEAT IT?
One of the most promising areas is immunotherapy, which harnesses the patient’s own immune system to fight the cancer. A study published in February this year used engineered bacteria to find and enter tumours, where the bacteria could deliver drugs that help the immune system to recognise and attack cancer cells.
Early diagnosis is also important. The sooner you catch a cancer, the less chance it has to evolve into something more difficult to treat. Another study published in February revealed the complete DNA sequences (genomes) of over 2,600 tumours, helping to pin down the different combinations of DNA mutations that can lead to cancer. It’s hoped that this research could help doctors to find and treat cancer much earlier in its development – perhaps even preventing it before it starts.