Illness," said Susan Sontag, "is not a metaphor." Cancer, she said - and she had it at the time - isn't a curse. It's a "highly curable" disease. Well, yes. And no.
When you get it, cancer does feel like a curse. Having lumps hacked out of you can feel like quite a violent thing. So can being blasted with drugs, or X-rays that make you feel tired, or sick.
Some people get treatment in time and 'win'. Some people don't - and don't. But if cancer is a war the world is fighting, it isn't, say some world experts, a war that's going all that well.
Forty years ago, when Richard Nixon signed the US National Cancer Act, most Americans thought a cure would be found in five years. They thought that, if you could put a man on the moon, you could make sure a man wasn't killed by a few rogue cells.
They were wrong. You can put a man on the moon, but rogue cells aren't so easy to control. Rogue cells like their power. And they're getting more every day.
If you were an oncologist, you might feel a bit depressed. You might think it was bad enough for the people who had been blasted with X-rays.
You might worry about how they were going to pick themselves up and how difficult it would be to keep looking after their children, or doing their jobs.
But, if you were a health minister and worrying about budgets, you might give up. If, for example, you saw that, by 2030, there were likely to be 22million new cases of cancer in the world in a year.
You might wonder why it was that richer countries had more cancer than poorer countries and why poor countries got more cancer the richer they got.
You might wonder what was the point of getting richer if you were going to have to spend so much money treating all the people who were getting richer, who were getting cancer.
If you were a health minister, you would know that cigarettes kill more than half the people who smoke.
But you'd also know, if you had looked at all the studies, and not just at the cost of treatment, that the risk of cancer goes up if you eat a lot of processed foods, sugar, salt and red meat. Or if you drink a lot of wine, or beer, or spirits. Or if you don't do much exercise, or if you're fat. It's a shame it does. Most of us like drinking wine and beer and spirits and eating sugar and salt and red meat. Most of us like sitting down.
Most of us think it would be very nice if we could eat what we wanted and drink what we wanted. The truth is that the way we live is making us ill.
We can face this, or we can ignore it. We can still search for that magic cure.
We can tell people that their choices have nothing to do with big businesses, big marketing budgets and big profits. But if we do, we're going to need an awful lot of money to pick up the pieces and pay the bills.
"Curing cancer," said one expert at the World Oncology Forum, "is certainly more complicated than landing on the moon."
What he didn't say is that it's probably a lot easier to send a man to the moon than it is to turn back a tide.