Study results announced on Sunday at the annual meeting of the American Society of Clinical Oncology concluded that the breast cancer drug Herceptin showed prolonged survival in treating stomach cancer. Herceptin, which brought in sales of 1.4 billion in 2008, represents a class of drugs that treats patients based on their individual genetic makeup by specifically targeting enzymes or proteins as opposed to umbrella chemotherapy or radiation treatments. Herceptin treats patients whose tumors have an abundance of a protein called Her2. The study, sponsored by Swiss health company F.Hoffman-La Roche, concluded stomach cancer patients who received Herceptin in addition to standard chemotherapy lived a median of 13.8 months compared with 11.1 months for those who treated with standard chemotherapy alone. Roche is looking to expand the approval of Herceptin in hopes to target other cancers including lung, bladder, colorectal and prostate.