WASHINGTON — Survival rates for the leading forms of cancer have improved during the nation's generation-long war against the disease, but much of the improvement has resulted from earlier detection and more accurate diagnoses rather than better therapies, according to a major study by the General Accounting Office released Thursday.
In studying the treatment of the 12 most common types of cancers from 1950 to 1982, the report said nearly all the cases it monitored showed significant progress. However, much of the success was attributed to preventive measures, not treatment breakthroughs--a point that led to charges that the medical community has exaggerated claims in fighting the disease.
Rep. Ted Weiss (D-N.Y.), chairman of a House Government Operations subcommittee on human resources, which has jurisdiction over the National Cancer Institute, charged that the report raised "serious questions about the performance over the past several years of the $1-billion-a-year national cancer program."
Cancer institute officials hotly denied the charges, which echo accusations that have been made in the last year by some in the medical community who have advocated that the federal government reduce spending on cancer treatments and instead emphasize prevention efforts.
Release Held 'Managed'
One irate cancer official said the release of the report to the press was "managed" to give a misleadingly negative impression of its findings.
Officials of the GAO, Congress' investigative agency, declined to comment on whether they believed that Weiss' interpretation of their report was accurate.
The report focused on cancers of the lung, breast, colon, rectum, bladder, stomach, cervix, uterus, prostate and head and neck, as well as leukemia and non-Hodgkin's lymphoma. It cited varying improvements in the number of surviving patients, with the most significant changes recorded in treatment of leukemia and lymphomas and far less progress in many forms of lung and stomach cancer.
According to the report, rates of survival for the two most common cancers--tumors of the breast and lung--had risen respectively from 60% and 6% in 1950 to 75% and roughly 12% in 1982. Some of that improvement can be attributed to new therapies, the report said, but most of the change was a result of earlier detection, particularly of breast cancer.
Gains in Therapies
However, in cases of leukemia and lymphoma, new therapies had produced dramatic increases in survival rates, the report said, citing an increase in the cure rate for leukemia from 10% in 1950 to 33% in 1982, with even higher rates for leukemia among children.
In still other cancers, most notably uterine tumors, the report said new treatments combining surgery with radiation had shown definite improvements, though not all patients were receiving those therapies.
Critics of the cancer institute contend that survival rates--the percentage of people diagnosed with a given type of cancer who remain alive five years later--have not increased fast enough to justify the amount of money the government spends on its anti-cancer effort.
"Rather than putting so much money into research for the rare cancers, put it into education and early detection," says Dr. Steven Piver, chief of the Gynecologic Oncology Department at Roswell Park Memorial Institute in Buffalo, N.Y. Cancer researchers resist such suggestions because "it's much more glamorous to write a grant for a rare disease like leukemia than to write a grant for screening for rectal cancer," he says.
But Dr. Lester Breslow, dean emeritus of the School of Public Health at UCLA, contends that survival rates are a "simplistic and misleading" way to measure progress against cancer. While rates have shown at best mixed improvement, he argues, other measurements are far more positive.
"For all persons born since 1935, there has been improvement" in cancer death rates, Breslow says. Only in older people are cancer death rates continuing to increase, he says, and that increase is caused entirely by lung cancer deaths attributable to smoking.
"The important thing that people don't understand" is that the government already spends a large amount of money on cancer prevention and that most of the $1-billion budget of the cancer institute does not go into trying new therapies, said Dr. Greg Curt, deputy director of the institute's division of cancer treatment.
"Sixty-five percent of the cancer budget is dedicated to fundamental research on cancer biology, and by anyone's estimate that's been a spectacular success," Curt said.