This spiral CT image of the chest shows a large malignant mass (purple) in one lung. A conventional chest X-ray could have missed this tumor, radiologists say. Medical Body Scans/Science Source hide caption

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Marder says immunotherapy has side effects but is less tiring than chemotherapy. Claire Eggers/NPR hide caption

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An artist's illustration shows lung cancer cells lurking among healthy air sacs. David Mack/Science Source hide caption

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Sally O'Neill decided to have a double mastectomy rather than "do a wait-and-see." Richard Knox/NPR hide caption

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Some images of lung cancer are clear cut. But in many others, a nodule on the screen turns out not to be cancer at all. hide caption

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Dr. Joel Policzer checks on his patient, Lillian Landry, in the hospice wing of an Florida hospital in 2009. A new study found that many terminally ill cancer patients don't fully understand their prognosis. J. Pat Carter/AP hide caption

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Back in 1998, Colleen Maxwell, then a 23-year-old student, smoked outside a San Diego bar, just weeks after California became the the first state in the nation to to ban smoking in most bars and gambling casinos. Joan C Fahrenthold/AP hide caption

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Dr. Steven Birnbaum positions a patient inside a CT scanner at Southern New Hampshire Medical Center in Nashua, N.H., in June 2010. Jim Cole/AP hide caption

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