Research presented last week at a major cancer research conference suggests that morphine, which is regularly prescribed to cancer patients to treat pain, may actually spur cancer growth. For the past seven years, the notion that opiates might stimulate cancer growth has slowly been gaining attention in the medical research community, beginning with anecdotal evidence that patients treated with alternative pain maintenance regimes—or those given opiate blockers during treatment—tended to survive longer than patients treated with the routine pain relief medications. And two studies presented in Boston last week at a meeting of the American Association for Cancer Research, the National Cancer Institute, and the European Organization for Research and Treatment of Cancer, demonstrate that in lab cultures and live mice, blocking opiate exposure to cancer cells limited both growth and spread of the disease.