"A dramatic turning point."
"No small matter."
If you listened to the mainstream media last week, you might have thought that the end of cancer was in sight. The cancer death rates are down at last, we were told, for the first time in over 70 years. "It's a notable milestone," said Dr. Michael Thun, head of epidemiological research for the American Cancer Society (ACS).
"That's momentous news," said Andrew C. von Eschenbach, director of the US National Cancer Institute. "It proves that our expectation of continued progress against cancer is well founded."
When you look more closely at the statistics in question, however, you find that the advance is more symbolic than substantive. A review of US death certificates by the National Center for Health Statistics found that the number of cancer deaths had dropped to 556,902 in 2003. In the previous year it had been 557,272. That represents a decline of 370 deaths. That's right, just 370 out of 557,272 cases, or around seven hundredths of one percent (0.066) between 2002 and 2003. At that rate, cancer deaths in the US should be entirely eliminated by the year 3508, which is a little more than 1,500 years from now.
While deaths fell in men by 778, at the same time they rose by 409 in women. Didn't hear about that, did you? In an alternate universe, the headlines might have read: "Cancer Deaths Among Women on the Rise!"
There was really not much new in this news. In fact, the death rates for several kinds of cancer have been falling slightly for about a decade, a fact that has been easily discernable in the annual graphs published by the ACS. However, apologists for conventional therapy jumped on the latest bandwagon and tried to attribute this minuscule change to improvements in diagnosis and treatment. I will clarify why I do not feel this is a likely explanation.
The most noticeable change in cancer statistics over the last few decades has been the decline in deaths from stomach cancer (gastric carcinoma). In 1930, the US death rate from gastric carcinoma in men was around 38 per 100,000. Today, it is around 6.9 per 100,000 for men and 3.4 per 100,000 for women. But this dramatic decline had little or nothing to do with improvements in diagnosis or treatment; indeed, outside of radical surgery for early stage disease, there are still no effective treatments for most cases of gastric cancer. Adding chemoradiation after surgery will only extend life by an average of nine months (Macdonald 2001).
Experts are unsure of the reason for this demographic shift, but some attribute the falling stomach cancer death rates in the US to a variety of environmental causes, such as better food preservation, better dietary habits, and a down turn in Helicobacter pylori infection associated with dietary improvements.
The most precipitous death rate decline in recent years started around 1990, when lung cancer deaths among men began falling. The rate has continued to drop steadily ever since. Many commentators have pointed out that most of this decline can be attributed to a reduction in cigarette smoking. In 1965, 42 percent of all American adults age 18 years and older smoked; in 2003, only 22 percent smoked. Although 45 million Americans continue to smoke cigarettes, the decline in smoking has been reflected in a parallel drop, albeit delayed, in lung cancer mortality among women as well as men.
In other words, cancer incidence and deaths rates tend to change over time, and that can be independent of any new treatments or diagnostic procedures. To suggest, without evidence, that the decline is due to improved medical care is simply unwarranted, and smacks of self-promotion.
Prostate cancer deaths have also declined since 1990, but here the reasons are even less clear. I think it is premature to declare that this decline is due to more widespread screening or to more effective treatments. In fact, a recent large study concluded that screening men for elevated levels of prostate specific antigen (PSA) or utilizing the older technique of the digital rectal examination (DRE) does not actually save lives. John Concato, MD, and colleagues at Yale University, New Haven in a study of 71,000 veterans, failed to show any benefit from either PSA or DRE used as screening method. The paper was published in the Archives of Internal Medicine (an AMA publication) on January 9, 2006.
But this sobering fact has not dampened the self-congratulatory mood at the American Cancer Society (ACS). "For years we've proudly pointed to dropping cancer death rates even as a growing and aging population meant more actual deaths," said John Seffrin, PhD, ACS chief executive officer. "Now, for the first time, the advances we've made in prevention, early detection, and treatment are outpacing even the population factors that in some ways obscured that success."
But wait a minute! Where are the studies to prove that the modest decline in prostate cancer deaths is actually due to improvements in diagnosis and treatment? Dr. Seffrin's triumphant statement about the efficacy of early detection is undercut by the factual Concato study. I am also unaware of any dramatic improvements in prostate cancer (PC) therapy over the past few years that could account for this decline.
One could with more plausibility point to the dramatic growth of PC support groups, such as US TOO, a cancer information and support network. Many men with PC are now speaking to each other, attending lectures by experts, and taking charge of their own health, the way women with breast cancer have done for many years. They are more proactive about seeking out the best treatments. From my experience, they are also exercising more, watching their weight, and becoming involved in the preparation of food. Finally, they are exploring the use of supplements, some of which have been shown in various studies to positively impact prostate cancer survival. For instance, a randomized controlled trial from Holland recently showed that a mixture of supplements (soy isoflavones, lycopene, silymarin and antioxidants) led to "a 2.6 fold increase in the PSA doubling time from 445 to 1,150 days for the supplement and placebo periods." In other words, it significantly slowed the growth of prostate cancer (Schroder 2005), which could lead to a reduction in the death rate.
Why is it that when ACS and others in the cancer establishment speculate on the reasons for the decline in prostate cancer deaths they exclusively focus on the things that oncologists do (such as diagnosis and treatment) but fail to acknowledge the contribution made by patients themselves through diet, exercise, supplements, etc.?
According to other reports, "one of the most important reasons for the decline in deaths is a huge shift in how technology is helping medical professionals screen for cancer" (Seben 2006). But I repeat: changes in screening and diagnosis have little if anything to do with this decline in cancer deaths. In fact, as has been convincingly shown by William Black, MD, and Gilbert Welch, MD, of Dartmouth Medical School, Hanover, NH, what we are doing as a society is inflating the number of people diagnosed with cancer through the over-diagnosis of "pseudo-cancers" – that is, the detection of asymptomatic and often totally harmless precancerous lesions that in many cases would never progress to full-blown malignancies (Welch 2005).
I would also point to another factor that may be responsible for diminishing the number of registered cancer deaths: the decline of autopsies. Cancer registries such as the NCI's SEER database rely exclusively on information provided by death certificates, and death certificates by no means always list cancer as the cause of death, even when a patient has been in the advanced stages of the disease in the months leading up to his or her death.
Autopsies are the most reliable means of establishing the actual cause of death. Pathologist Elizabeth Burton, MD, of Louisiana State University, New Orleans, studied this problem for ten years. She and her colleagues performed 1,105 autopsies. One hundred and eleven malignant cancers were discovered in 100 of these bodies, which had either been misdiagnosed or had gone entirely undiagnosed during life. In 57 of these patients, the immediate cause of death was attributed to the undiscovered cancers. "The discordance between clinical and autopsy diagnoses of malignant neoplasms [cancers, ed.] in this study is 44 percent," they wrote (Burton 1998).
George Lundberg, MD, then editor-in-chief of the Journal of the American Medical Association, in which Burton's article was published, explained that this startling data called into question all cause-of-death data in the United States. Upon re-evaluation, he said, cancer might turn out to be far more prevalent as a cause of death than conventionally realized.
Dr. Lundberg lost his job soon after these comments. According to ABC News, he was fired in part for criticizing doctors "for having moved away from performing large numbers of autopsies." To this day, the decline in autopsies is a factor that is almost never discussed in relation to cancer mortality statistics.
It is also striking that the country with some of the highest cancer death rates, Hungary, also has the highest rate of autopsies in Europe. In other words, there are probably many more cancer deaths in Western societies than meet the eye. The seeming "decline" in cancer mortality statistics may be due, in part, to a failure to look for it as a cause of death.
And even when a death is ultimately a result of cancer, the immediate cause of the patient's demise may not be recorded as such, but as something else - pneumonia, hemorrhage, or abdominal obstruction leading to peritonitis, for example. This is not even to mention deaths from acute toxicity due to treatment itself, or deaths due to complications of surgery for cancer, which are also generally not recorded as cancer deaths. The aforementioned Dr. Welch has found, for example, that "some deaths that are conventionally attributed to surgery are not being attributed to the cancer for which the surgery was performed" (Welch 2002).
Together, this combination of overdiagnosis of pseudo-disease and underdiagnosis of occult (hidden) cancer makes any statistic on the absolute number of genuine cancer deaths very much a matter for debate. And correspondingly, since death rates are calculated on the assumption that incidence and prevalence figures are a genuine measure of the amount of cancer in a population, the figures for death rates are equally debatable. As Welch and Black have pointed out, the use of 'cancer-specific death rates' as the measure of treatment effectiveness in clinical studies obscures the very real possibility that deaths from treatment itself are being systematically overlooked in the statistical calculations.
TO BE CONTINUED, WITH REFERENCES, NEXT WEEK
--Ralph W. Moss, Ph.D.
0.375 sec, (6)