Cancer: Its Cause and Treatment, Volume 2 (of 2)

by Lucius Duncan Bulkley

Recognizing, then, that cancer is a great and widespread disorder of nutrition, let us consider some of the facts regarding its extension and some of the influences concerned in its production.

Sex.—Cancer is much more frequent in females than in males. In the United States Mortality Reports for 1914 there were 31,138 females to 21,282 males; thus, in a total of 52,420 deaths from cancer 59.4 per cent were in females, with a preponderance of 9,856. This excess is largely due to cancer of the breast, from which there were 5,423 deaths, and cancer of the female genital organs, causing 8,152 deaths, of which 7,470 were from cancer of the uterus.

The death rate in males, however, seems to be increasing of late years; in the United States in 1912 males formed 39.7 per cent; in 1913, 40.1 per cent; and in 1914, 40.6 per cent. In England, according to Williams, the proportion of males to females is increasing much more rapidly. This greater mortality of males is due to the greater number of deaths from cancer of the stomach and liver, buccal cavity, and skin. In 1914 there were 19,889 deaths from cancer of the stomach and liver, or 37.9 per cent of the whole number; of these 10,122 were in males to 9,767 in females, or an excess of 355 males, whereas in 1912 the females were 87 in excess. In the United States the cancer death rate for males has increased since 1901 31.8 per cent and for females 25.3 per cent.

Age.—Carcinoma is exceedingly rare under 20 years of age, most malignant tumors at that period being sarcomata. After 25 the number of deaths from cancer about doubles each five years up to 40, and then increases steadily, until the actually greatest number of deaths, 6,909 (3,071 males, 3,838 females), occurred between 60 and 64 years of age, after which they decreased steadily; there were 267 deaths at 90 and over, 8 of them being 100 years and over. At no period did the deaths of males exceed that of females, and from 35 to 39 years of age the latter were almost three times that of males.

Occupation.—Many attempts have been made to trace the influence of occupation upon the incidence of cancer, but thus far very little of practical interest has been demonstrated; the difficulties concerning this investigation are immense, owing to absence of essential and accurate data. There have been many lists presented, but few of which agree as to details, and all need to be corrected as to the proportion of those living at different ages. There is also the question as to the effect of local or general agencies; thus, as to the result of local injuries on the skin, and also in regard to other agencies, whatever they may be, which produce internal cancer; for tables of occupation do not generally refer to sex, age, or location of the disease.

First, to dismiss the question as to the direct result of local injuries in inducing cancer of the skin, which, at the most, caused only 3.7 per cent of all cancer deaths in 1914, we may cite a few instances in which this appears to be pretty well established.

The occurrence of epithelioma as a direct result of repeated and protracted exposure to X-ray is familiar to all, and is particularly interesting because it occurs commonly among younger persons, and at a time of life when epithelioma is rare; and especially also because the X-ray is constantly effective in curing epithelioma. The rarity of epithelioma resulting from X-ray, considering the enormous amount of exposure which must have occurred in making and using X-ray tubes, implies, however, that there must be some other cause also at work. It has been urged, therefore, that the skin tissue being altered and weakened from repeated and protracted exposure to X-rays, more readily falls prey to some of the chemical or other irritating agencies which have been observed to be followed by epithelioma.

Time does not permit even a mention of the various elements, which are many, that have been credited as excitants of cutaneous epithelioma; but brief allusion may be made to one which formerly attracted much attention, mainly in England; this refers to chimney-sweeps cancer, the mortality from which was at one time at least 5 times greater than that from cancer in males generally, at the same age. This is now, however, of relatively infrequent occurrence, owing to the adoption of other methods of cleaning chimneys. The epithelioma, which more commonly developed on the scrotum, was believed to be due to the long continued irritation caused by the constant presence of soot on the part; other products of combustion and tar derivations have also been accredited with the same result.

The question of the influence of occupation along other lines is really more interesting, because more obscure; but a careful study of available data tends to show the correctness of the thesis on which my former lectures and these are based. This, as you know, is that our so-called advancing civilization, with all its errors of life, in many directions, is at the bottom of the steady increase in the mortality from cancer.

One of the most interesting contributions to this was the investigation made by Dr. Latham, Registrar-General, in a study of cancer returns in England; this showed that the mortality from the disease was more than twice as great among well-to-do men having no specific occupation as among occupied males in general, the respective mortality ratio being 96 for the former and only 44 for the latter. The same observation has been made elsewhere.