This page is from the original Don't Let Me Stop You blog. We have moved to a new site: Visit DLMSY on WordPress.

Sunday, May 14, 2006

Cancer Statistics

So how goes the war against cancer? Many people believe, erroneously, that there is a "cancer epidemic" today. More people are dying from cancer than in the past, but why is this?
  • Deaths from other causes have been reduced, but the overall mortality rate will always be 100%. Progress against cancer has been slower.
  • Diagnostic techniques have greatly improved, so deaths from "unknown" or non-specific causes (e.g. "old age") that were actually cancer are now correctly identified.
  • The average age of the US population has been increasing, and cancer is more common in older people.
These distortions in the mortality statistics of cancer cause, among other things, an irrational fear of "chemicals." In fact, literally everything is made of chemicals, and the distinction between "natural" and "man made" chemicals is virtually meaningless.

Similar distortions affect the statistics suggesting huge advances against cancer. Although there is no cancer "epidemic" and some forms of cancer are quite curable today, for other types progress remains elusive. One of the technical talks at the AACR described problems with interpreting cancer statistics. The speaker began with a Will Rogers quote, "When the Okies left Oklahoma and moved to California, they raised the average intelligence levels in both states." He noted that a population of cancer patients generally includes some whose disease is actually in a more advanced stage than is realized. If improved diagnostic techniques allow these patients to be correctly "staged," the survival statistics improve for both groups, even though no real treatment progress has been made. The early stage group will obviously have a longer average survival time when those with more advanced disease are removed. Less obviously, the shifted patients are also healthier than the average patient with advanced disease, so that group's statistics improve as well.

The ongoing, successful quest for ever earlier diagnosis has the same distorting effect on survival statistics. Finding the cancer 5 years earlier brings in patients that are likely to live about 5 years longer than the previous patient population even if treatment is not improved at all. Often these patients are easier to treat, too, improving the statistics even more.

Overheard at a Cancer Meeting

Last month we attended the annual meeting of the AACR, a large scientific conference devoted to cancer research. Not surprisingly, there's a strong concensus among cancer researchers that much more federal spending should be directed at cancer research.

One day at lunch with a group of strangers the others were talking about a campaign for US Senate in a southern state. One candidate was a distant relative of one of my companions. "Is the candidate conservative?" asked another companion with obvious concern. "No," responded the original speaker, reassuringly, the candidate is a "sensible liberal." It was clear the entire group regarded "sensible liberal" as practically redundant. We were reluctant to assert that if "sensible liberal" is not an oxymoron, the species is nearly as rare as the jackalope.

This Desert Life - Jackalopes

Contrary to popular belief The Great American Desert is not just a vast, desolate wasteland. It is literally teeming with creatures of all types, from the mundane to the exotic. The most prized trophy among local big game hunters is the fierce and wily jackalope.

The hunting of jackalopes is not for the faint of heart, and a successful hunt is extremely rare. Wikipedia notes that President Ronald Reagan "had a rabbit head with antlers, which he referred to as a 'jackalope,' mounted on his wall. Reagan liked to claim that he had caught the animal himself. Reagan's jackalope hangs on the ranch's wall to this day."

The origins of the jackalope remain somewhat obscure, according to Wikipedia:
The jackalope is said to be a hybrid of the pygmy-deer and a species of killer-rabbit. Reportedly, jackalopes are extremely shy unless approached. It has also been said that the jackalope can convincingly imitate any sound, including the human voice. It uses this ability to elude pursuers, chiefly by using phrases such as "There he goes! That way!". Although no jackalope has ever been captured alive, it is said that a jackalope may be caught by putting a flask of whiskey out at night. The jackalope will drink its fill of whiskey, and its intoxication will make it easier to hunt. It is also legend that the Cherokee Indians would eat these at the end of a vision quest.
There is also a card in the Magic: The Gathering game called Jackalope Herd. Fittlingly, the artwork for the card was done by Nebraskan, Ron Spencer. We also enjoy the "flavor text" for the card, "There’s little more demeaning than getting your butt kicked by a bunch of bunnies." Just ask Jimmy Carter about that.