During the last two years, a lot has been written—and said—about the dangers of cigarette smoking, especially as a possible cause of the alarming increase in cancer of the lung. But there is still much confusion about the tobacco-cancer issue. Most of the scientists who have given thought and study to the matter appear to agree that an association between cigarette smoking and cancer of the lung does exist. Whether that association is one of cause and effect is as yet unanswered in terms of major scientific opinion.
One of my colleagues expresses the situation in this way: If it has not been proved that tobacco is guilty of causing cancer of the lung, it has certainly been shown to have been on the scene of the crime. The American Cancer Society, along with a growing body of professional and scientific opinion, has taken this position: Although the complicity of the cigarette in the present prevalence of cancer of the lung has not been proved to the satisfaction of everyone, yet the weight of evidence against it is so serious as to demand of stewards of the public welfare that they make the evidence known to all.
Most authorities on the subject agree that before the early years of the twentieth century, cancer of the lung was encountered rarely. In a monograph on lung cancer which was notable in its day—1912—Adler could base his review on a mere 374 cases. Today cancer of the lung takes the lives of about as many white males each year as were reported to have died of all forms of cancer combined in 1900. During the period 1930-1948, the death rate from lung cancer among men rose from 5.3 per 100,000 to 27.1—an increase of 411 per cent. Some part of this remarkable increase can be laid to better and more widely available diagnosis, but the net impact of the factor of better diagnosis is considerably weakened by noting the trends in the post-mortem experience in large hospitals over the years. Cancer of the lung was perhaps less generally recognizable forty or fifty years ago than it is today—but that was hardly true in the autopsy room. Cancer of the lung now constitutes a substantially larger proportion of the total autopsy findings than it did thirty years ago.