> The thinking used to be that smoking was “almost the only cause of lung cancer,” said Dr. Maria Teresa Landi, a senior investigator at the National Cancer Institute, which is part of the National Institutes of Health.

Well, that tells a lot: overfocusing on a single cause because it is obvious and major. Well, let us hope the medical science learns this lesson.

ETA: not that I blame them, it is a reasonable attitude but not so good in science.