Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: TUESDAY, February 18, 1992 TAG: 9202180101
SECTION: EXTRA PAGE: E-6 EDITION: METRO
SOURCE: Jane Brody
DATELINE: LENGTH: Long
DRUG THERAPY USED AS `MOP-UP' FOR BREAST CANCER SHOWS PROMISE
The initial jolt delivered by a diagnosis of breast cancer is often followed by a great debate over how the disease should be treated.Thanks to the efforts of some very tough women and a few courageous doctors who dared to challenge therapeutic dogma, radical mastectomies have been replaced almost entirely by less disfiguring but equally effective surgery, with or without radiation therapy.
But cancer specialists also realized that for a significant percentage of breast cancer patients, therapy cannot end with removal of the detectable tumor. Too many patients with seemingly early disease that is confined to the breast area nonetheless suffer a recurrence and eventually succumb to the disease.
This realization prompted a new debate that led to a further modification in therapy: the use of drugs to mop up any residual cancer cells that could seed a regrowth of cancer and become life-threatening.
At first the drugs, called adjuvant therapy, were recommended only for women whose cancers had spread to nearby lymph nodes. Even though the drugs made women temporarily ill, early studies showed they could help prevent or delay recurrence and postpone death in such women, who otherwise face a 50 percent chance of having their cancer return.
Then experts focused on women whose lymph nodes were seemingly free of cancer cells when their breast tumors were treated. About 30 percent also will suffer a recurrence, usually within five years of initial treatment.
Shouldn't they too be offered a chemical mop? Would potential benefits be worth the treatments' discomforts and risks, and which patients are likely to benefit most from which treatments?
Now, thanks to a remarkable report published last month, some encouraging answers are beginning to emerge that could have lifesaving significance for thousands of American women each year.
The report summarizes the results of adjuvant therapy among 75,000 women with "early" breast cancer and gives reason to believe that a significant dent can be made in deaths caused by this disease, which will afflict one out of nine American women.
The report, which collated the 10-year results of 133 well-designed studies worldwide, clearly demonstrated the lifesaving value of adjuvant therapy with drugs or hormones for women whose cancers seem confined to the breast or the lymph nodes under the arm.
The combined studies, published in two consecutive issues of the British medical journal the Lancet, clearly showed that adjuvant therapy was not merely a stopgap measure to delay the inevitable. Rather, the therapy can significantly improve a woman's chances of remaining alive and free of cancer 10 or more years.
The beneficial treatments studied included chemotherapy with a combination of three cancer-killing drugs, the anti-estrogen drug tamoxifen and measures like surgery, radiation or drugs to stop ovarian function. The report explored the separate and combined benefits of these treatments for women of different ages and stages of disease.
It indicated clearly for the first time that nearly all patients could benefit and that the benefits are lasting. Only women with very tiny cancers confined to the milk duct in which they arose would not be expected to benefit, since surgery alone cures nearly 100 percent.
The new findings surprised the 78 cancer experts who directed the original studies. They had expected the modest benefits seen after five years either to remain the same or to diminish with time. Instead, they found that as the years passed after treatment was stopped, there were continuing improvements in survival.
As Dr. Richard Peto, director of cancer studies at Britain's Oxford University who headed the research team, pointed out: "Mortality differences at five years don't just persist or disappear, as many had feared. Instead, the benefits at 10 years are twice as good."
The improvements, although still modest, are nonetheless highly significant and meaningful to women who want to maximize their chances of beating breast cancer. Overall, for every 1 million women given the additional treatments, an extra 100,000 would be alive 10 years later, the analysis showed.
The improvements in survival were most dramatic for women whose cancers had spread to the nodes and who consequently had a lower survival rate when treatment was limited to removal of the original tumor.
For every 100 such women given adjuvant treatment, an additional 12 would be alive 10 years later, whereas for women whose nodes were free of cancer at the time of initial treatment and whose survival rate is already about 85 percent to 90 percent at five years, an additional 12 patients out of every 200 would survive for at least 10 years.
The analysis also showed that some women may not have to use powerful chemotherapeutic drugs to achieve a significant improvement in survival. Instead, tamoxifen alone or stoppage of ovarian function alone can sometimes yield results as striking as those associated with chemotherapy.
In other cases, combining such hormonal treatments with chemotherapy yields survival improvements that exceed either one alone.
Tamoxifen also proved to be a cancer preventive. Those taking it for two to five years had a 39 percent reduction in their risk of developing cancer in the other breast.
There also seemed to be a decreased risk of dying of a heart attack for those on tamoxifen, which is more effective at lowering cholesterol than most medications intended for that purpose, Peto said. Chemotherapy given for six months was as effective at prolonging life as that given for longer periods. - The New York Times
Jane Brody writes about health issues for The New York Times.