Genetic Test May Spare Chemotherapy [10/25/2001; Associated Press] LISBON, Portugal (AP) - A new genetic test on breast tumors could spare thousands of women every year from post-operative chemotherapy and its side effects and help tailor treatment for those who need it, cancer experts said Wednesday. About 20 or 30 percent of women with early breast cancer will have a recurrence within five years, but because doctors can't identify those most at risk, they give chemotherapy in nearly every case. The new method could cut the proportion of women given chemotherapy unnecessarily from today's level of 90 percent in the United States and 70 percent in Europe to 27 percent overall, according to the research presented at a conference of the European Federation of Cancer Societies. Dr. Bruce Ponder, a leader in breast cancer genetics and professor at Cambridge University in England, said the approach holds promise. ``If you take 100 women who have got breast cancer and ... they have very similar tumors, we know that some of them will do well and some of them will do badly and we don't know which they are and so at the moment we tend to treat all of them on the basis that they might do badly,'' Ponder said. ``It's almost certain that some breast cancers respond to some treatments and some respond to other treatments and that's because of the molecular makeup of the tumor,'' Ponder said. ``What these sorts of analyses will do ... is allow us to use the treatment that we have already more effectively - to tailor treatments to individual patients.'' Chemotherapy reduces the risk of cancer recurrence by about 35 percent, but many women suffer unpleasant side effects, including nausea, hair loss, diarrhea and fatigue. ``You are sparing a lot of women unnecessary toxicity and you're saving time too because if you can pick up what is the optimum treatment for them ... at least you've got the best chance of success with minimum distress and toxicity to the patient,'' Ponder said. The approach is one example of how the recent unraveling of the human genetic code is starting to pay off. Breast cancer recurs if undetectable cancer cells derived from the main tumor are already elsewhere in the body at the time of surgery. Some tumors send out such microscopic outposts, while others don't. Doctors cannot currently tell which ones do, so chemotherapy, which kills cancer cells lurking anywhere in the body, is given after surgery to most women just in case their tumors are the type that do. In the United States, drugs are given whenever the breast tumor is bigger than half an inch in diameter, or to about 90 percent of patients. In Europe, the drugs are administered when the tumor is larger than 1 inch, when the woman is over 35, when the tumor is not fueled by the female hormone estrogen or when it is classed as aggressive. Those conditions together include 70 percent of cases. However, cancer will not have spread in 70 percent to 80 percent of those women. The new test is designed to tell scientists whether the tumor has sent microscopic cancer cells to other areas of the body, so they can better determine who should get chemotherapy. In the study, Laura van 't Veer, a pathologist at the Netherlands Cancer Institute in Amsterdam, studied the activity of 25,000 genes in breast tumors of 78 patients who were treated for early breast cancer between 1983 and 1995, before women were being treated with chemotherapy after surgery. The disease later recurred in 34 of those women and the other 44 remained cancer free. She examined how active each of the genes was in every tumor in both groups. A pattern emerged, giving her a signature unique to the tumors that had spread to other parts of the body. Experts say the test should be available in about five years. Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.