Haunted by the loss of her beloved aunt to breast cancer, Allison Salvatore, 29, has felt a sense of on and off doom throughout her twenties. She imagines she herself will suffer the same fate and tries to dodge that sword of Damocles by eating healthfully and doing breast self-exams, often and anxiously. She’s tempted by the new gene test and its promise of an end to her unfocused angst. But she never pursues it for fear it will confirm her worst nightmare.

Salvatore is like a lot of women trying to process the implications of gene testing—suspended between hope and terror. Breast cancer has long been a disease cloaked in menacing uncertainties. So with mid-Nineties’ discoveries of the BRCA1 and BRCA2 genes, and the testing that soon followed, scientists hailed these exciting breakthroughs as desperately-sought pieces to the puzzle. But for women whose lives have been touched by breast cancer, directly or indirectly, gene testing is the proverbial mixed bag. An answer would be great, but only if it’s the right answer. The prospect of getting a positive result looms like a death sentence and frightens many women away from testing.

Perhaps if women were to know that experts have recently brought even more clarity to the gene-testing issue, they’d feel better equipped to overcome needless anxiety and take positive action. New, more definitive guidelines about whom to screen should reassure women like Salvatore, who needn’t get tested. (And hopefully, eligible women will feel motivated to pursue it.) At the same time, women who test positive can avail themselves of recent recommendations targeted to them and the latest findings about breast cancer prevention. Rather than feel helpless and doomed, they can take steps shown to reduce the risk of developing the disease.

Who should be tested

Last year, experts zeroed in on candidates for gene testing. Based on the results of a study involving 12 leading U.S. cancer centers, they determined that all women with breast cancer diagnosed under age 50 and any woman with a history of breast or ovarian cancer in a close relative (mother, sister) should be screened for BRCA1 and BRCA2. These mutations account for about 7% of all cases of breast cancer.

Ideally, a woman should be tested at a teaching hospital, which offers genetic screening for research purposes. In this setting, she’s granted a high degree of confidentiality that helps protect her from insurance and employment discrimination, says Kenneth Offit, M.D., M.P.H., Chief of Clinical Genetics Service at Memorial Sloan-Kettering Cancer Center in New York City and author of the recent book Clinical Cancer Genetics (published by John Wiley). Making sense of the test results within the context of personal and family medical history is key to approximating individual risk and tailoring follow-up care options to fit a woman’s life and wishes.

What should you do if you test positive?

A few years ago, some of the nation’s top breast cancer experts, including Dr. Offit, devised and issued guidelines for the follow-up care of women who test positive for one of the breast cancer genes. Here are the key recommendations, plus more recent advice based on the latest findings about breast cancer prevention.

• Begin breast self-exam (BSE) by age 18 to 21 years, to establish a regular habit and to get acquainted with what feels normal for your breasts. Though early results from a recent study cast doubt on the value of BSE, the final verdict on its ability to detect malignancies won’t be in for another few years. Until then, BSE is still considered a key tool for women, especially those at high-risk.
  
  
• Consider going for clinical breast exams every six months to a year, starting at age 25.
  
  
• Begin getting yearly mammograms at least by age 35 and as early as age 25. You and your doctor can pinpoint the specific start date, based on your preference and the readability of your baseline mammogram. Get mammograms at the same place, so that prior films are available for comparison.
  
  
• If you carry a gene mutation, go for ovarian cancer screening every six months. Because BRCA2, and especially BRCA1, are also linked to ovarian cancer, women must be screened for this disease if they test positive. Ovarian cancer is notoriously difficult to detect in its early stages while it’s still treatable. So it’s important to find a doctor’s office or hospital that combines the use of two screening tools in order to increase test sensitivity: a blood test for CA-125 levels (a tumor marker) and transvaginal ultrasound, ideally using a machine with both a “color-flow Doppler” and “morphology index,” two recent advances that identify tumors more accurately.
  
  
• Ask your doctor about taking tamoxifen. The drug, long used to treat breast cancer, has now been shown to prevent the disease, too. It cut the risk of breast cancer in half among women susceptible to developing it, according to a new study sponsored by the National Cancer Institute (NCI). However, your doctor will monitor you closely because tamoxifen can also raise your risks of uterine cancer and blood clotting.
  
  
• If you are BRCA1 positive, discuss the pros and cons of using the Pill, which may reduce your risk of ovarian cancer. And a recent large-scale study disputes the Pill’s reputed link to breast cancer: Though experts found a slight increase in breast cancer risk, they speculate it reflects better detection, since women are examined by their doctors more frequently when they get their Pill prescriptions renewed. The tumors detected in Pill users tended to be less advanced than those found in non-users.
  
  
• Stick to a diet rich in fruits, veggies, and fiber; avoid alcohol; and exercise regularly. Though experts haven’t specifically examined whether a healthy diet and exercise lowers the risk of women with defective genes, it’s smart to take these steps since studies of average-risk women have shown encouraging results. In one study, for instance, exercise reduced the risk of breast cancer in all women, especially in premenopausal and younger postmenopausal women.
  
  
• Consider prophylactic oophorectomy (PO). Surgical removal of the ovaries does not guarantee prevention of ovarian cancer (case reports show that the disease can still develop after the procedure), but it may substantially reduce your risk. That’s an important ray of hope, considering ovarian cancer’s dismal survival rate due to widespread late detection. Here’s another surprising benefit of PO: It slightly reduced the incidence of breast cancer, according to a study by NCI experts, possibly because removing the ovaries significantly lowers levels of estrogen and progesterone—hormones associated with the development of breast cancer. Experts at the National Institutes of Health have recommended that women with 2 or more first-degree relatives with ovarian cancer be offered prophylactic oophorectomy after childbearing is over or at age 35—a decade or more before the disease usually strikes.
  
  
• Consider prophylactic mastectomy. Like PO, a prophylactic mastectomy (PM) does not eliminate the risk of getting breast cancer, since breast cells are left behind on the chest wall. But experts at the Mayo Clinic in Rochester, Minnesota recently found that even in women with a strong family history, removal of both breasts lowered the risk of getting the disease by a whopping 91 percent.

Carolyn Hagan is an award-winning women’s health writer for national magazines including Glamour, Mademoiselle, American Health, Good Housekeeping, Fitness, and Child. She frequently writes about breast cancer.

THE LATEST PROGRESS ON THE GENE FRONT A new gene-based drug can improve the outcome of women with metastatic breast cancer, or disease that has spread to distant organs. Called Herceptin, the drug has been shown to shrink tumors in women with an aggressive type of breast cancer that accounts for up to 30% of all cases. The drug arrests the cancer by blocking the action of so-called HER2, a faulty gene that makes a protein that promotes tumor growth. Right now, only women with advanced cancer can be tested to see if their tumors are HER2-positive. But according to NCI, plans are well under way to test Herceptin in women with earlier stage disease to see if they, too, may benefit.