The social distribution of cancer of the scrotum and cancer of the penis.

In a paper (1) from this Institute published 20 years ago attention was drawn to the very distinct social distribution of cancer of the scrotum. The data were derived from the death certificates of the 921 cases of cancer of the scrotum and cancer of the penis, reported from England and Wales in 5 years (1913, 1914, 1921-23). As neither the numbers of males engaged in the various occupations nor the age distributions were then available, a preliminary survey was attempted by calculating the ratio of the cases of these two forms of cancer to one another. Data that have come to light since then, showing that the incidence of cancer of the penis is comparatively uniform in the different Social Classes (Table V), make clear that this basis of comparison was not so defective as it appeared at the time. The occupations of the 921 persons were grouped in 8 classes (Table I), of which the first 3 comprised those where there is especial exposure to known carcinogenic materials. In the first 3 of these classes cancer of the scrotum is more frequent than that of the penis, as one would expect. The ratio, cancer of the scrotum:cancer of the penis is 1:20 in the agricultural workers, who are mostly agricultural laborers, and is nearly 8 times greater, or 1:2.6, in the nonagricultural laborers (Class 6a). Those engaged in lighter manual labor (Class 6b) have a lower proportion of scrotal cancer than have those performing the heaviest work (Class 6a). The clerical and light manual workers (Class 7) have a low ratio of scrotal cancer (1:9.2). The suggestions drawn from these results may be stated here in the words of the earlier paper. "Roughly, it seems safe to say that the heaviest work, such as that of classes 4, 5 and 6a, is done by those who wash least; these three classes consist very largely of town dwellers and show a high proportion of scrotal cancer. The two classes which show the lowest proportion are the clerical and light manual