Environmental Health News

What's Working

  • Garden Mosaics projects promote science education while connecting young and old people as they work together in local gardens.
  • Hope Meadows is a planned inter-generational community containing foster and adoptive parents, children, and senior citizens
  • In August 2002, the Los Angeles Unified School District (LAUSD) Board voted to ban soft drinks from all of the district’s schools

#641 - The Cancer War Grinds On, 10-Mar-1999

In 1996 Donna Shalala, U.S. Secretary of Health and Human Services,
declared that the war on cancer was finally showing results. "This
looks like a turning point in the 25-year war on cancer, and it should
be cause for celebration by every American," she said.[1] Shalala made
her dramatic pronouncement to underscore the fact that the death rate
for all cancers combined had declined 2.6% during the period 1991-1995.
It was the first sustained decline since the government started keeping
cancer statistics in the 1930s.

Cancer deaths declined for cancers of the lung and prostate in men,
breast and uterus in women, and colon/rectum in both sexes. Since these
are the most common cancers, they drove down the overall death rate.

We suspect that these reported trends are questionable because
reputable studies indicate that many cancers remain undiagnosed unless
an autopsy is performed, and autopsy rates have declined in recent
years (see REHW #631).

However, for purposes of discussion, let's assume that the government
is right, that age-adjusted deaths from all cancers combined really did
decline 2.6% between 1991 and 1995.

Despite this bit of good news, the details of cancer in this country
are still awful. Cancer struck 1,228,000 Americans for the first time
in 1998, and 564,800 Americans died of cancer in 1998.[2] A man's
chances of getting cancer during his lifetime are now 48% (about 1 out
of 2) and a woman's chances are now 38% (about 4 out of 10). Clearly,
we have a very long way to go before we can claim that the "war on
cancer" has been won.

Furthermore, the good news about cancer hides some terrible injustices.
For example, the largest declines in cancer death rates between 1991
and 1995 occurred among African-Americans. The death rate for all
cancers combined declined 5.6% among blacks between 1991 and 1995. The
decline was especially great among black men, whose cancer death rate
decreased 8.1%, compared to black women, who experienced a 2.5% decline
during the same period.

Despite this good news, the overall age-adjusted cancer death rate is
still 40% higher among black men compared to white men, and 20% higher
among black women compared to white women.[1]

Why do blacks die of cancer so much more than whites? The Director of
the National Cancer Institute, Richard Klausner, phrases it delicately:
"less access to care and less aggressive treatment" play a role, he
says.[1] Less aggressive treatment? There is an extensive body of
literature showing that many physicians give second-class medical care
to black patients.[3] Perhaps this occurs because blacks tend to be
poorer than whites, but perhaps it also results from a widely-shared
(and perhaps subconscious) racist view that blacks deserve less than
whites.

The "cancer establishment" has a ready explanation for the declining
death rates from all cancers combined. They say roughly half the
overall 2.6% improvement in cancer death statistics, 1991-1995, can be
accounted for by improvements in "life style" -- less smoking, better
diet, more exercise. They say the other half results from better
diagnosis and treatment -- more people are being kept alive by
chemotherapy, radiation, and surgery.

But Richard Clapp at the Boston University School of Public Health
points out that heart disease is caused by these same factors --
smoking, bad diet and insufficient exercise.[4] Because of improvements
in these factors, deaths from heart disease have declined 49% during
the past 25 years. If heart disease and cancer are caused by the same
factors, why has the cancer death rate remained so high? It cannot be
simply that cancer is a disease of old age. Heart disease, too, is a
disease of old age. Is something else besides "life style" factors
causing cancer? It is a fair question.

We note that in a 1990 cancer prevention booklet titled EVERYTHING
DOESN'T CAUSE CANCER, the National Cancer Institute (NCI) says, "Many
cancers could be prevented by reducing our exposure to carcinogens."[5]
The NCI identifies 30 chemicals or industrial processes that are known
to cause cancer in humans. Furthermore, NCI says, "Of the several
hundred other chemicals that cause cancer in animals, however, it is
not known how many are also human carcinogens. Nevertheless, materials
that cause cancer in one type of animal usually are found to cause
cancer in others.... For these and other reasons, we should expect
animal carcinogens to be capable of causing cancer in humans."

The NCI goes on to explain why weak cancer-causing chemicals cannot be
reliably identified among the 70,000 chemicals now in industrial use.
In a typical test of a chemical for carcinogenicity, "groups of about
50 mice or rats of each sex are exposed to the test substance at
different dosages for about two years." At the end of the experiment,
the animals are killed and examined for cancer.

NCI goes on: "In the human population, large numbers of people are
exposed to low doses of chemicals, but the total impact may not be
small at all. For example," NCI says, "a carcinogen might cause one
tumor in every 10,000 people exposed to it, which may not seem great.
But exposure of 230 million Americans would result in 23,000 cancers --
a public health disaster."

NCI goes on: "We obviously could not identify a carcinogen that causes
one cancer in every 10,000 exposed mice by running the test on only 50
mice. To detect such a low cancer rate, we would need tens of thousands
of mice. This would cost many millions of dollars per test. Testing
more than a few chemicals in such a fashion would be too expensive and
time-consuming," NCI says.

NCI also points out that it is difficult to identify which carcinogens
cause which cancers because "A chemical that causes cancer of the liver
in mice, for example, might cause cancer of the breast in rats and
cancer of the bladder in humans."

Is there a safe level of exposure to a cancer-causing chemical? NCI
says no: "There is no adequate evidence that there is a safe level of
exposure for any carcinogen." And "Low exposure that might be safe for
one person might cause cancer in another.... Unfortunately, scientists
have not yet developed any way to measure a person's individual risk.
Exposure to a low level of a carcinogen thus has to be considered a
risk for everyone," NCI says.

Here is the big picture of cancer: Table 1 shows that during the last
45 years, the incidence of all cancers combined has risen 1.0% each
year and the death rate for all cancers has increased at the rate of
0.2% each year. If we exclude lung cancer, the increase in the
incidence of all other cancers is still 0.8% each year for the past 45
years, but the death rate has declined at the rate of 0.4% each year. A
rising incidence and a dropping death rate, taken together, mean more
people are learning to live with cancer.

--Peter Montague (National Writers Union, UAW Local 1981/AFL-CIO)

=====

[1] Mary Jo Hoeksema and Catherine Law, "Cancer Mortality Rates Fall: A
Turning Point for the Nation," JOURNAL OF THE NATIONAL CANCER INSTITUTE
Vol. 88, No. 23 (December 4, 1996), pgs. 1706-1707.

[2] Lynn A.G. Ries and others, SEER CANCER STATISTICS REVIEW, 1973-1995
(Bethesda, Maryland: National Cancer Institute, 1998).

[3] For example, see the first 19 studies cited in Kevin A. Schulman
and others, "The Effect of Race and Sex on Physicians' Recommendations
for Cardiac Catheterization," NEW ENGLAND JOURNAL OF MEDICINE Vol. 340,
No. 8 (February 25, 1999), pgs. 618-626.

[4] Richard W. Clapp, "The Decline in U.S. Cancer Mortality from 1991
to 1995: What's Behind the Numbers?" INTERNATIONAL JOURNAL OF HEALTH
SERVICES Vol. 28, No. 4 (1998), pgs. 747-755.

[5] National Cancer Institute, EVERYTHING DOESN'T CAUSE CANCER [NIH
Publication No. 90-2039] (Bethesda, Maryland: National Cancer
Institute, March, 1990).

Search terms: cancer; carcinogens; heart disease; morbidity statistics;
mortality statistics; national cancer institute;