The Centers for Medicare & Medicaid Services (CMS) will cover [CT-scans of the lungs] for individuals age 55-77 years with a 30 pack-year smoking history and who currently smoke or have quit within the past 15 years (one pack-year = smoking one pack per day for one year; 1 pack = 20 cigarettes).Maybe a bit too cautious. I'm thinking of my aunt who smoked from age 18 to 50, then totally quit. Lung cancer suddenly attacked at 73 and killed her within a year. Before that sudden return, she had been getting regular checkups including X-rays, and nothing showed. She assumed that she had quit in time. The limit of 15 years since quit wouldn't have accounted for her situation. Obviously some forms of lung cancer can hide longer than 15 years. Omitting the limit wouldn't cost much more, because those delayed ambushes are not common. Most smokers keep going until they explode the oxygen tank.
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