Could it be that the cancer in her lungs was just a mass that settled in her lungs, as they do in other parts of the body? Is lung cancer only caused by smoking?
There is a PSA on most radio talk shows from time to time warning of Radon gas and saying it's "the second leading cause of lung cancer."
Do they get that data from death certificates? I didn't know the cause of lung cancer was so easily determined. Some gov't agency is the sponsor of the Announcement.
Radon collects in basements of home built on hard rock formations. It must be vented from below as it is heavier than air, like chlorine and carbon dioxide.
From a Google:
"Cancer is a class of diseases characterized by uncontrolled cell division and the ability of these cells to invade other tissues, either by direct growth into adjacent tissue (invasion) or by migration of cells to distant sites (metastasis). This unregulated growth is caused by a series of acquired or inherited mutations to DNA within cells, damaging genetic information that define the cell functions and removing normal control of cell division. ...
http://en.wikipedia.org/wiki/Cancer