The lack of a conclusion by a panel of experts last week about whether to give drug treatments to women with early breast cancer -- that has not spread to the lymph nodes -- leaves the approximately 80,000 women per year who are diagnosed with the problem with little help in confronting a devastating dilemma.

Seventy percent of them will be cured by surgery, without the need for toxic chemotherapy or for tamoxifen, a hormone-like drug whose long-term side effects are still uncertain. But 30 percent will suffer a recurrence of their tumor in the absence of further treatment, and drugs can prevent or delay about a third of those recurrences. The problem is, nobody can identify with certainty which women have cancers that are destined to recur.

Should all women opt for extra therapy? Some experts say yes and would choose to treat all so that a few might benefit. Others say that doctors can use a combination of laboratory tests to place up to half of women with early breast cancer in a low-risk category; for this group, these experts say, the benefits of drug treatment are probably not outweighed by the risks and the cost.

The controversy over so-called "systemic adjuvant therapy," as the drug treatments are called, was ignited last year when the National Cancer Institute issued an urgent bulletin stating that all women with early breast cancer should be "considered" for such therapy.

Some cancer experts have called that advice premature, pointing out that the 10 large studies on the subject have so far not shown conclusively that giving chemotherapy or tamoxifen to such patients significantly increases their survival rates.

The reduction seen in the rate of cancer recurrence may only be buying women a little time, not curing them. Researchers said it may take up to a decade of further study to detect any effect of the drugs on long-term survival.

In the meantime, last week's consensus conference at the National Institutes of Health was supposed to help cancer patients by offering guidance in deciding which women are at the highest risk of recurrence and thus most likely to benefit from drug therapy.

Instead, it tossed the ball back to women and their doctors, urging that they either enroll in scientific studies or make their own decisions.

"It was totally wimpy. They avoided making any kind of direct recommendations," said the NCI's Bruce Chabner, an aggressive proponent of drug therapy. "There's a tremendous amount of evidence that's accumulated in the last few years to show that you can select out high-risk patients -- and I think they should be treated."

William McGuire, chief of medical oncology at the University of Texas Health Science Center at San Antonio, shared Chabner's frustration. McGuire said he believes that up to half of early breast-cancer patients are at low risk for recurrence and probably do not need drug treatment.

"I don't think it {the panel's report} leaves the reader, the consumer -- our constituents -- with a reasonable notion of where we are with adjuvant therapy," he said.

John H. Glick, director of the University of Pennsylvania Cancer Center, predicted that the report will add to the confusion. "I think it is going to confuse patients and physicians because they were not given the kind of guidelines for which I think the data was available," he said.

The panel said that a woman with early breast cancer who chooses not to enroll in a scientific study of alternative treatments should work with her own doctor to estimate the chances that her cancer will recur, and then decide whether drug treatment is warranted. That assumes that both doctors and patients will have the knowledge and the relationship they need to make a complex decision at a highly stressful time in the women's lives.

"The moment between the impact of the disease and the choice of treatment is a very short period," said Aron Goldhirsch, coordinator of the International Breast Cancer Study Group in Lugano, Switzerland. "Everything comes on you in a huge cascade. You need to rely on a group of people who must give you some fundamental guidance."

Experts at the conference said a series of tests done at the time the tumor is removed can help provide that guidance. The panel concluded that certain tests should be done routinely, and that the system for interpreting them should be better standardized in hospitals around the country.

McGuire, an expert in the use of such predictive tests, said he believes doctors can use such information to place up to half of all patients with early breast cancer in a "low risk" group, whose chance of recurrent cancer is so small that drug treatment is unnecessary.

Such patients would include those with very small tumors, tumors confined to the breast's milk ducts, and tumors with a combination of favorable test results.

He said another third of patients fall into a high-risk category: those with tumors measuring more than three centimeters or those with a combination of unfavorable test results, such as an absence of hormone receptors. He routinely recommends drug treatment for such patients.

The remaining patients fall into a "gray area" where some test results are favorable and others are worrisome.

The decision for or against drug treatment depends upon the doctor's opinion and the patient's wishes. "It's really the patient who has got to make the decision," McGuire said.

Cancer chemotherapy has more short-term side effects than does tamoxifen. It causes nausea and vomiting, temporary hair loss, fatigue, and drops in blood counts that make patients anemic and put them at risk of infections.

But studies have not borne out early fears that giving chemotherapy to women with early breast cancer would increase their risk of other cancers in later life.

Long-term tamoxifen has been used safely in patients with advanced breast cancer for many years, but recent Swedish studies suggest that it may increase the risk of cancer of the endometrium, the lining of the uterus. However, the NCI's Chabner said other studies suggest it may reduce the risk of osteoporosis and heart disease.

Researchers emphasized that even if a woman with breast cancer has every available test to assess her risk, no expert can guarantee that her tumor will not recur or that a given treatment will prevent recurrence.

Breast cancer is notoriously unpredictable, and the best a patient and her doctor can do is to make an informed bet. Marc Lippman, director of Georgetown's Lombardi Cancer Center, said the consensus report, by its very nature, fails to help them do that.

"They don't say if you want to put your money on red or black," he said. "They wind up saying roulette's a dangerous game."

There are a variety of tests designed to help find women who would benefit most from aggressive therapy for breast cancer.

Those considered to be of crucial importance and which should be performed routinely include:

Tumor size: The larger the tumor, the more likely it is to have spread.

Estrogen and progesten receptor status: If the cancer cells respond to these hormones, the cells retain some of their original pre-cancerous qualities, suggesting a less aggressive cancer.

Nuclear grade: Pathologists examine the nucleus of the cancer cell and grade it for its normal or abnormal appearance. The higher the grade, the more aggressive the cancer is believed to be..

Histological type: The entire cell is graded according to its appearance. A high grade means a more aggressive cancer.

DNA flow cytometry: A fragment of genetic material from the tumor cell is examined with special equipment to determine if there is an abnormal number of chromosomes, and whether the cells are synthesizing new DNA at a fast rate, which would mean the cancer is growing quickly.

Her2/nu oncogene: Some breast cancers contain extra copies of this gene, believed to signal an aggressive cancer.

Newer and promising, although not completely proven tests:

Cathepsin D: Cancer cells produce this enzyme-like substance apparently to help them nourish themselves from the tissue they are invading. High levels appear to suggest a virulent cancer.