All statistics from various localities show that cancer has certainly increased in frequency very greatly of late years, and though some have attempted to claim that this increase is only apparent, and is due to greater accuracy of diagnosis, and the prolonging of more lives to an age when cancer is more common, there is no doubt in the minds of those who have studied the figures that the increase is certainly very real; and unless there be found some way to check its production, the death rate at the end of the century will be appalling.
It is quite impossible here even to give a comprehensive idea of the immense amount of work which has been given to the study of the statistics of cancer in various parts of the world, as collected in the remarkable works of Roger Williams and Jacob Wolff, but brief mention must be made of some of the items observed and recorded in order to properly understand our subject. Williams in particular has analyzed the recorded facts in an interesting and convincing manner, and shown again and again in connection with the figures from different countries, sections, and cities, that the occurrence of cancer bears a striking relation to the condition of the people in reference to their material prosperity; namely, that the well-to-do, who can overindulge in many ways are vastly more subject to cancer than those in the poorer walks of life; also that aborigines in the wilder parts of the world are either almost exempt from cancer, or suffer from it to a very much less degree than civilized foreigners who come to their lands. This is also shown in a very striking manner by Wolff, and I present here a table which he gives in regard to the progress of cancer in a single country, Australia, among the native born and foreigners.
| OF 100,000 LIVING THERE DIE OF CANCER IN AUSTRALIA | ||||
|---|---|---|---|---|
| Year | Number of Inhabitants | Native Born | English | Other Nationalities |
| 1851 | 403,889 | 28 | 14 | |
| 1861 | 1,153,973 | 5.6 | 30.5 | 19 |
| 1871 | 1,168,377 | 9.7 | 56.7 | 25 |
| 1881 | 2,252,167 | 16.8 | 72.9 | 32.6 |
| 1891 | 3,183,237 | 19.8 | 119.8 | 45.9 |
| 1901 | 3,771,715 | 22.6 | 203.1 | 57.3 |
He remarks, “We see from this comparison in what a great degree the death rate from cancer has increased in foreigners as compared to the native born, in whom the disease has remained about stationary, when the increase in population is considered.” Another writer remarks that when native Australians mingle with foreigners as servants or employés, and adopt their diet and customs, cancer occurs more frequently in them. Much the same has been reported in regard to other peoples and nationalities, and later we will consider the influences of urban life on the production of cancer.
In New Zealand, according to Hislop and Fenwick, where the general death rate is the lowest in the world, cancer is on the increase, as civilization advances. In the great majority of cases the alimentary canal is the seat of invasion, even in women: all the patients studied were hearty eaters, taking also very much strong tea many times daily.
The Polynesians and Melanesians seem to be peculiarly exempt from cancer. Sir William McGregor, although he had operated several times on whites in the Fiji Islands, never remembers operating on a Polynesian or Melanesian, who are practically vegetarians. He never saw a case in British Guinea in 9½ years, and then saw an encephaloid cancer of the tibia in a Papuan, who for 7 or 8 years had lived practically a European life, eating canned Australian meat daily.
In regard to Africa, Williams quotes Dr. Madden of Cairo, who says, “The consensus of opinion among medical men in Egypt is, that cancer is never found, either in male or female, among the black races of that country. These include the Berberines and the Sudanese, who are all Mussulmans, and live almost entirely upon vegetable diet.” Of 19,529 deaths among natives of Cairo during 1891, only 19 were due to cancer (females 10, males 9) or 1 in 1028. In England during the same year the proportion of cancer deaths to total deaths was 1 in 29. In the Islands of Lagos, on the West Coast of Africa, Dr. Johnson, in 14 years’ practice there saw 5 cases of cancer in natives all of whom lived as Europeans. In southern Africa, “among the Boers and Europeans, who are large flesh eaters, malignant tumors are common: but among the natives, who are mainly vegetarians, these tumors are so rare as to be almost unknown.”
Renner reports interestingly in regard to cancer among the descendants of liberated Africans or Creoles, in Sierra Leone, Africa. During 30 years, from 1870 to 1900, there were but 20 cases recorded as malignant disease among 22,453 admitted to the Colonial Hospital: in the next ten years there were 26 among a total of 10,163, a slow but steady gain in cancer incidence, with the advancing influence of the white man. He says that while the aborigines eat no meat, the “Creoles” eat much meat; the teeth of the latter are beginning to decay, like those of the whites, which is attributed to the sweets introduced by the latter. Every case of cancer recorded has been in a Creole, living like a European, and not a single case among the aborigines.
Much the same freedom from cancer has been noted in regard to negroes when first brought to the United States in slavery, when their food and mode of life was simple: but since emancipation and in proportion as they have mingled with whites and eaten their food, with their own natural tendency to gluttony and laziness, cancer has increased among them, although their death rate from malignant disease is still much less than that of whites.
In India all writers agree that cancer is rare among the inhabitants of warmer country districts, where they live largely on rice or millet, with a little milk and butter, and vegetables: they eat meat rarely, the immense majority of the people live a rural life, depending upon agriculture for their sustenance.