After about two years, 40 percent of both groups were alive, suggesting that medicines are enough and that these women can be spared the ordeal of having all or part of a breast removed.
A second study by Dr. Atilla Soran of the University of Pittsburgh Medical Center of nearly 300 women in Turkey also suggests surgery is not helping, though there were hints that some groups did better or worse. Surgery seemed to help if cancer had spread just to bone, and it appeared to do harm if it had spread to the liver or lungs.
“These are incredibly important, big-deal studies,” said Dr. Claudine Isaacs, a breast specialist at Georgetown University’s Lombardi Comprehensive Cancer Center. Many doctors jumped on earlier, less rigorous studies and advised women to have surgery, and this should be a warning against that, she said.
The results also may spur interest in a U.S. study on the topic. Dr. Seema Khan of Northwestern University in Chicago has had so much trouble recruiting participants that she lowered her goal and may not be able to answer the question.
“There’s a huge amount of bias” among doctors and patients about what is best, she said.
Most breast cancers are found at an early stage, and many women are treated with surgery followed by hormones or chemotherapy, plus radiation. But cancer medicines have gotten so good at lowering the risk of a recurrence that doctors wonder whether the radiation is still needed. It can cause heart and other problems, especially in older women, and three or four weeks of daily treatments can be a burden.
Dr. Ian Kunkler of the University of Edinburgh in Scotland led a study of 1,326 patients 65 or older with early-stage cancers whose growth was driven by hormones. This is the most common form of the disease and the age group that accounts for most cases. Half were given radiation and half skipped it.