Cancer is sometimes called a disease of aging. In general, the older a person is, the higher the risk of contracting cancer. In 1975 the lifetime risk of being diagnosed with cancer in the UK was twenty-five percent. However, by the 1990s this had risen to thirty-three percent and by 2010 it was forty percent. The reason for this rise can be explained by the increases in life expectancy over this time. People are living longer, therefore the risk of being diagnosed has crept up.
But, this does not mean that cancer is only a disease of old age. Young adults can get cancer too, as can children, and even babies. How can this be? How can the young come down with this disease, if it is considered to be age-related? Certain genetic markers can increase the risk of cancer, as can environmental factors. These can massively increase the chances of cancer developing at a younger age in certain individuals. So, how can we consider the overall lifetime risks?
Think of the human lifespan like a game of Chinese Whispers. I’m sure you are aware of the game, but just in case, here’s a brief summary. The players stand in a line, and the first player whispers a message to the second player, who whispers it to the third, who whispers it to the fourth, etc, etc. Now, in the real world, the point of the game is to compare the message received by the final player to the original message. The version in this example is slightly different. In our game, the aim to keep the message going as long as possible. The more times that the message is repeated intact, the longer the game goes on (and, as the length of the game is a metaphor for the human lifespan, the longer the individual stays alive). Over time, the message will become corrupted and each change is analogous to age-related deterioration (wrinkles get bigger….memory starts going….joints get stiffer….did I mention memory starts going?) And eventually, at some point, the message will become so corrupted it becomes nonsense. And that’s the end of the game – and the end of the person’s life!
Now, imagine a different sort of ending to the game. In this version, the message gets corrupted as before. But, this time, the changes to the message are such that it becomes dangerous. So, when the player who erroneously makes the final change to the message whispers it to his/her neighbour, the neighbour becomes outraged, turns around and punches the player who whispered the now dangerous message. That player then blames his/her predecessor and thumps them, who then takes it out on their predecessor and so on, and so on…..until eventually all of the players are involved in a massive brawl. In this version, the outcome for the individual is cancer.
This is why cancer is linked to aging. The longer the game goes on, the longer the lifespan of the individual. But, also, the longer the game goes on, the bigger the risk that the message will become corrupted in such a way that it becomes fight-inducing. But how do we explain the genetic and environmental factors which can increase the incidence of cancer in younger individuals? Well, first of all, as a metaphor for genetic factors, imagine a game where some of the players have hearing difficulties. As a metaphor for environmental factors, imagine the game being played in the middle of a rock concert. In these games, the chances of the message getting corrupted are massively increased and it is likely that the game will end up in a fight sooner.
So. Keep your ears clean. Listen carefully. Keep your game going as long as you can. And watch out for that smack in the mouth.
AG McCluskey (2015). Chinese Whispers Zongo’s Cancer DIaries