VAN NUYS, Calif.: A California physician has developed a new diagnostic method for treating some breast cancer tumors. Dr. Melvin Silverstein, a surgical oncologist, announced a system Wednesday that could prevent excessive treatments that many women now undergo. The process assigns points to three characteristics of the common DCIS (for ductal carcinoma in situ) tumors. The tumor's final "score" determines whether it can be safely ignored, removed, or treated with radiation or a mastectomy. Now, tumors are often treated too aggressively with radiation or breast removal that may be unnecessary. "Right now we do not know which tumors are going to develop into breast cancer, and which will not," says TIME medical writer Christine Gorman. "This process could give us a way to determine which to treat, and which to leave alone. Similar tests are performed for colon cancer." Although Silverstein warned that more research must be done before the system's efficacy can be confirmed, an initial study of 333 women yielded encouraging results. Physicians will diagnose more than 30,000 cases of DCIS this year, as mammography technology becomes more widely used.