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ANALYSIS-In war against cancer, progress is in the eye of the beholder

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* Deaths rates fell an average 1.5 percent per year, 2000 to
2009

* In men, mortality rose for melanoma, cancers of liver and
pancreas

* Much of improvement in incidence, mortality reflects less
smoking

By Sharon Begley

NEW YORK, Jan 7 (Reuters) - As the United States enters the
fifth decade of its "war on cancer," deaths continue to decline,
according to an exhaustive report based on official data
released on Monday.

But that doesn't tell the whole story, say experts not
involved in the report from the National Cancer Institute, the
American Cancer Society and other groups on progress against
cancer since the 1970s. The improvements reflect such lifestyle
changes as not smoking more than they do the billions of dollars
spent to discover and implement advanced cancer treatments.

"We don't look at this as progress," said Fran Visco,
president of the National Breast Cancer Coalition, of the new
numbers. "This is such incremental improvement, when you look at
the decades of investments, the cost of treatments, the number
of researchers and journals, and then at the number of people
who die ... well, we are clearly doing something wrong," said
Visco, who was not involved in the study.

The decrease in deaths from all cancers - 1.8 percent a year
for men and 1.5 percent for women from 2005 to 2009, the last
year with enough data to analyze - while steady, is
disappointing to many experts because it is no greater in the
most recent five-year period than in the previous one, and
because it has hardly been affected by supposed advances in
detection and treatment.

"The decrease in cancer mortality is driven largely by the
decrease in cancer incidence, which is mostly because of the
decrease in smoking," said Dr. Otis Brawley, chief medical and
scientific officer of the American Cancer Society (ACS).

Smoking can cause more than a dozen cancers, including lung,
head, neck, bladder and mouth.

Although improvements in treatment for breast and some other
cancers have cut death rates, Brawley said, headline-making new
drugs have contributed little. "Most of the expensive new drugs
prolong survival for no more than three or four months," on
average, he said.

INCIDENCE OF CANCER FALLS

At first glance, the findings in the report, published in
the Journal of the National Cancer Institute, are worth
cheering.

In men, the incidence of cancer fell an average 0.6 percent
a year from 2000 to 2009, find the researchers, who include
scientists from the NCI, ACS and other federal agencies and
private groups. In women, cancer incidence was flat for those
years but rose 0.6 percent a year from 2005 to 2009. (The
statistics are adjusted to account for the aging of the
population, since cancer is largely a disease of the elderly.)

Cancer incidence among women fell when fewer post-menopausal
women opted for hormone-replacement therapy following a 2002
report that linked it to breast cancer and other disease, said
NCI's Brenda Edwards, the lead author of the report.

But no other factor occurred to cause another dip after the
mid-2000s. Instead, although the incidence of breast cancer fell
from 2000 to 2009 by an average 0.7 percent a year, it rose 0.9
percent a year from 2005 to 2009.

The trend in childhood cancer is also going in the wrong
direction. From 2000 to 2009, cancer incidence among children 19
and younger rose 0.7 percent per year, on average.

Experts are not sure why the numbers are rising. But one
reason may be, paradoxically, greater access to health
insurance.

An uninsured child who developed flu-like symptoms in the
1990s might have died from what was actually leukemia, but
without medical care his death certificate said pneumonia,
explained ACS's Brawley. With insurance, that child now is more
likely to see a doctor and get correctly diagnosed.

Experts note that cancer incidence can be affected by such
changes as how many people are screened for the disease, such as
through mammography or prostate-specific antigen (PSA) tests.
That may account for the recent increase in cases of thyroid and
kidney cancers.

Incidence is therefore less accurate an indicator of
progress against the disease than mortality. By this measure,
too, progress has been halting at best, the report finds.

Death rates from cancer - the percentage of all deaths due
to any form of this disease - have been declining since the
early 1990s, by about 1.8 percent per year in men and 1.4
percent per year in women. But the decrease was also 1.8 percent
per year from 2005 to 2009 for men, and 1.5 percent for women.
So even as expensive new treatments were introduced, progress is
not accelerating.

"We're all wondering why there hasn't been an acceleration
in the rate of decrease" in mortality, said report co-author
Edgar Simard, an epidemiologist at ACS.

One reason is that "cancer cells are wily foes," said
Massachusetts Institute of Technology cancer biologist Robert
Weinberg. "What is most frustrating is the ability of cancer
cells that are under attack and being decimated by one therapy
to invent a way of circumventing the therapy and finding a new
way to thrive and proliferate."

Although the drop in smoking is responsible much of the
decline in cancer death rates - 42 percent of adults smoked in
the mid-1960s, compared with about 21 percent now - some of the
credit goes to improved screening.

Colorectal screening can find and remove polyps before they
become malignant, for instance. "So stage one never gets to
stage two or three or four, and you have less mortality," said
Dr. Maurie Markman, senior vice president for clinical affairs
at Cancer Treatment Centers of America. Deaths from colorectal
cancer fell 2.9 percent a year from 2000 to 2009 among men and
1.9 percent among women.

The 1.9 percent annual decline in deaths from breast cancer
over the same period probably reflects some improvements in
treatment. But "a huge driver of the decrease is what we call
breast awareness," said Brawley. "It's not monthly breast exams"
that do not decrease deaths "but women being aware of their body
and asking, what is this change in my breast?"

The rise in liver cancer may be the result of a high
prevalence of chronic hepatitis C infection resulting from drug
use decades ago, the report says. Obesity may be raising the
incidence of liver, pancreatic and uterine cancers.

"If the American public really wants fewer people to die
from cancer, then there will need to be major changes in
lifestyle," said MIT's Weinberg, such as declines in tobacco use
and obesity. The biggest reductions in cancer mortality "will
come from prevention rather than treatment."

(Reporting by Sharon Begley; Editing by Jilian Mincer and
Douglas Royalty)

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