Over the weekend, the American Society of Clinical Oncology hosted a major cancer conference in Chicago. Researchers presented data that may prove the potential for targeted therapies in treatment of several types of cancer. For example, researchers said crizotinib, a drug in development by Pfizer, caused tumors to stabilize or shrink in 90 percent of 82 patients with lung cancer who had ALK gene alteration. Another study found that Avastin, a Roche drug used to restrict blood supply to tumors, prolonged the life of women with ovarian cancer by four months when combined with chemotherapy. Bristol-Myers Squibb is developing ipilimumab, which activates the body’s immune system. In a study of 676 patients with melanoma, the drug extended the average life of patients by 3.5 months compared to patients taking another cancer vaccine named gp100. The heartening findings, however, are underscored by the high cost of the treatments—Avastin, for example, costs up to $56,000 a year.