WASHINGTON, Jan. 18 (UPI) -- The precipitous drop in U.S. cancer deaths reported by the American Cancer Society is a testament to the successful efforts of cancer prevention, research and treatment, experts said.
Yet they cautioned obstacles such as lack of access to healthcare hamper efforts to drive the rate down further.
From 2003 to 2004, the most recent mortality data available from the National Center of Health Statistics, cancer deaths fell by 3,014. In 2006 the ACS announced a decrease of 369 deaths between 2002 and 2003 -- the first time in more than 70 years cancer deaths had declined.
"What we reported last year was not a fluke, and it's much larger than was reported before," report author Ahmedin Jemal, strategic director for cancer occurrence at the ACS, told United Press International. "It's very exciting, and very good news."
Jemal mainly credits prevention for the drop: Smoking rates have gone down in recent years, and more people are getting screened for colorectal, breast and cervical cancers. Treatments have also vastly improved. For instance, new, sophisticated drugs are now tailored to attack certain cancers and extend the lives of those with cancers that have already spread. Researchers are regularly discovering genes behind types of cancers, which also aids in developing new treatments.
The drop in cancer deaths has even outpaced the exploding population of older Americans, Jemal said -- remarkable considering cancer is a disease of aging.
"We have the right to be cautiously but increasingly enthusiastic about the data," said Dr. Gabriel Hortobagyi, president of the American Society of Clinical Oncology.
The enormous investment in cancer research has also shown substantive results, particularly in clinical trials and drug development, Hortobagyi said.
Indeed, scientists are now reaping the benefits of the cancer research effort that began in the 1970s, and as a result, winning the war on the disease, said Dr. Geoffrey Wahl, president of the American Association for Cancer Research.
More research is needed to investigate the unknowns of cancer; for example, environmental agents may play a role in cancer development, Wahl said.
Yet the report's results should be tempered by the failure of many Americans to take control of their cancer risk, experts said.
For instance, if doctors applied everything they know about early diagnosis and treatment of cancer to all Americans, tens of thousands of lives would be saved, said Hortobagyi -- and that's just with existing knowledge.
"The reality is that we as a profession have not done our utmost to convince our society that these things need to be done," he said.
Wahl also emphasized Americans aren't getting the message that, at least to a degree, they can prevent cancer through healthy diets, limiting sun exposure and not smoking.
Around 20 percent of the U.S. adult population smokes cigarettes, despite overwhelming evidence of its detrimental effects. One in four Americans are now obese, an increase of 110 percent since 1990 and an increase of 6 percent since 2005. Obesity increases risk factors for certain types of cancer.
Breast cancer and colorectal cancer screening compliance stands at about 70 percent and 50 percent, respectively.
Excellent screening tools are meaningless if a person can't pay for the procedure -- a reality for about 46 million Americans who live without health insurance. In poor communities, many women do not get breast and cervical cancer screenings at the same frequency as their wealthier counterparts. The government does fund programs to fill these gaps, but funding is often unreliable.
The new report, published in the January/February issue of CA: A Cancer Journal for Clinicians and Cancer Facts & Figures 2007, also lays out a new model for more accurately predicting deaths. In 2007 experts believe 1.44 million Americans will get cancer and 560,000 will die from it.
The report also found:
-- Mortality rates have continued to decrease across all four major cancer sites in men and in women except for female lung cancer, in which rates continued to increase by 0.3 percent per year from 1995 to 2003.
-- Death rates from all cancers combined peaked in 1990 for men and in 1991 for women. Between 1990 and 2003, death rates from cancer decreased by 16.3 percent among men and by 8.5 percent among women.
-- Lung-cancer incidence rates are declining in men and appear to be leveling off in women after increasing for many decades.
-- Colorectal cancer incidence rates decreased from 1998 to 2003 in both males and in females.
Jemal and others are confident the decrease will continue in coming years, and the statistical model in the new report suggests the numbers will stay stable, said Linda Pickle, senior math statistician at the National Cancer Institute.
But Pickle also stressed the obvious: No one can safely predict the future. There could be a sudden change, either societally or otherwise, that shifts the outcome.
For instance, when former first lady Betty Ford was diagnosed with breast cancer in the 1970s, breast cancer diagnoses spiked because more women got screened. And in the 1990s men began to heed messages to get PSA tests for prostate cancer; rates for that cancer also spiked but have since fallen.
Whatever lies ahead, "we have to keep the momentum going," Jemal said.
For more information and to access the report: