Several diseases, one slot
The Ledger has one counter for every cancer. The illnesses inside it do not share a cause, an age, or a story.
The Ledger puts every cancer in one counter, rounded to 10 million deaths a year. The World Health Organization's count is in the same neighbourhood: nearly 10 million cancer deaths in 2024. The slot is a convenience. Lung cancer, bowel cancer, breast cancer, liver cancer and stomach cancer are different illnesses, at different ages, with different causes. They share a habit. Cells grow where they should not, and they keep going.
The large one
Lung cancer is the large one. WHO puts it at about 1.86 million deaths in 2024, more than any other cancer. Most of those deaths are from smoking. Smoke in the air, outdoors and in the house, also causes it. Bowel cancer is next in that list, then liver, breast and stomach. Adding them up makes a ticker. It does not make them one disease.
There is no single morning in Cape Town, South Africa, for this card, and no first cure. The heart transplant has a date and a ward. Cancer does not. What there is, is a study that was hard to wave away.
The doctors' letters
In October 1951, Richard Doll and Austin Bradford Hill wrote to every doctor on the British medical register and asked a plain question. Do you smoke, did you smoke, or did you never really smoke? About 40,000 replies were usable. They already knew the suspicious pattern. The year before, they had compared hospital patients with lung cancer to other patients, and the cancer patients were much more often smokers. A comparison like that can be argued with. People who are already ill remember their habits differently, and hospitals are an odd sample of the world. Following doctors who were well at the start is a stricter test. You write down the habit first, and you wait to see who dies of what.
Their first report from that wait was published in the British Medical Journal in June 1954, covering about two and a half years. Lung cancer deaths rose with the amount of tobacco. The doctors who had never smoked regularly sat at the bottom of that gradient. A second report, in 1956, found the same climb for heart attacks and for the chronic lung disease on another card of this dashboard. Cigarettes were never only a cancer story. They show up again under Cardiovascular Demise and under Respiratory Failure.
The rest of the slot
The counter still adds the rest in. A childhood cancer and a smoker's lung tumour both move this number, and they are not the same event. A death at eight and a death at seventy-eight look identical on a ticker and are nothing alike in a life. Infections cause a real share of cancers in poorer countries, human papillomavirus and hepatitis among them. Stomach cancer is tied, in many cases, to a bacterium that lives in the stomach lining. That last one has a famous anecdote attached, a doctor who drank the bacterium to prove it. It is a true story about ulcers, and about one cancer. It is the wrong story for a counter whose largest entry is the lung.
This is not health advice. It is a story about a population statistic. It says nothing about any one person's risk. If you have concerns about your health, speak to a doctor.
Sources
- WHO cancer fact sheet, including the 2024 figures for deaths by site.
- WHO lung-cancer fact sheet.
- Doll and Hill, 1954, “The mortality of doctors in relation to their smoking habits”, reprinted in the British Medical Journal.
- The British Doctors Study, at the unit in Oxford, England, that still holds it, including the 1956 report that added heart attacks and chronic lung disease.
- The annual figure used on the counter is the Ledger's own rounding, set out on the methodology page.