CAUSES OF CANCER

Evening Star, Issue 19792, 16 February 1928, Page 4

CAUSES OF CANCER

DANGEROUS HABITS METHODS OF PREVENTION CLINICS ADVOCATED. “It is not my wish to delude you into the belief that we have yet reached that desirable time when, by the adoption of certain precautions, we can relegate this dreadful disease to the obscure regions to which typhus fever, for example, has been banished. I want rather, if J. can, to bring before you certain facts and certain suggestions based on those facts which appear to offer some encouragement to us to think in terms of prevention, and not only of cure.” With the above statement Professor Blair Bell, professor of obstetrics and gymecology m the University of Liverpool, and director of the Liverpool Medical Research Organisation, introduced a. lecture at the Institute of Public Health, London, on ‘ The Prevention of Cancer,’ the term cancer being used synonymously with “malignant disease.” “malignant neoplasia,” and including “sarcoma” (statesthe ‘Manchester Guardian’). Lord Dawson of Peun presided. Such a statement, said Professor Bell, was not a confession of failure, but was indicative rather of the mentality produced by the frequent sight of cases lieyond all possibility of cure—cases in which the disease might never have occurred if the. simplest of preventive measures had been adopted, or which might have been cured ff seen at an earlier date. Hence, while ns a second line of defence treatment at the commencement of the disease should be earnestly advocated, the first line of defence always will be prevention._ The fact cannot be overlooked that, if prevention were carried out on the public health lines to be suggested, machinery would be brought into existence whereby cases of cancer would more often be detected in the early stages of the disease. The peril was so great that if we failed soon to conquer this disease, a few years hence nations would not be fighting ono another, but would have united to stamp out a horror that might threaten the very existence of mankind. He did not agree with those who asserted that the rapid increase in the mortality rate of malignant disease must reach a peak, and then recede. It appeared, rather, that, if unchecked by science, cancer would only cease to exist when there was no longer material on which it could develop. A GROWING MORTALITY RATE. There seemed little doubt that the mortality rate from cancer in most civilised countries was on the increase, in support of which view Professor Bell gave the following statistics showing the deaths from cancer per million persons living in England and M ales : 1847-1350 274 1851-1855 306 1356-1860 327 1861-1865 ... 067 1866-1870 403 1871-1875 445 1876-1880 494 1881-1885 548 1886-1890 632 1891-1895 712 1896-1900 800 1901-1905 867 1906-1910 039 1911-1915* 1,055 1916-1920* 1,182 1921-1925 1,269 1926 1,362 "Civil population only.

In eighty years the death rate of malignant disease had increased fivefold, and this had gone hand in hand with improved diagnosis. The actual numbers of persons whose deaths in 1916 and 1926 were recorded as being due to malignant disease are shown in the following table :

1916. 1926

Estimated total population 36,480,000 39,069,000 Death from all causes ... 508,217 453,084 Death from cancel* 40,630 63,-0 From these figures it was clear that in 1916 of all deaths from birth upwards one in every twelve was due to cancer, and in 1926 ono in every eight deaths. In 1926, between the ages pf forty and fifty years one in every six deaths was due to cancer, and between the ages of fifty and seventy years one in every four. In the list of causes of death in England and Wales malignant disease now stood third. Little need be said regarding age, for it was well established that in old age cancer _ was more frequent than in the middle period of life. Of 53,220 deaths from malignant disease in 1926 only 2,448 occurred in persons under the age of forty years. SUSCEPTIBILITY OF WOMEN. The sex of the person appeared at first sight to be of some moment, for more women than men died of the disease, but over the age of forty years this might be dependent on the greater number of women in the population. In the age periods under forty years in 1926 five females to every three males died of the disease—namely, 1,551 females and 897 males, Sex predilection seemed, however, to be intimately connected with the site of the disease. According to the published figures relating to the year 1925, it was evident that of organs similar in the two sexes, the stomach and intestines, including the rectum, were most frequently affected. In males, out of 24,002 deaths, from cancer, 10,739 were due to disease in the organs mentioned, and in females, out of a total of 27,937 deaths from malignant disease 9,857 occurred in these organs. But in women the reproductive organs were singularly prone to malignant disease. In the same year, however, whereas in males the number of deaths from malignant disease of the lips, tongue, mouth, jaw, tonsils, pharynx, and oesophagus numbered 4,622, in females cancer at these sites caused only 1,032 deaths. From

the statistics quoted we gleaned that malignant disease was very rare still—in spite of individual impressions—before the ago of forty years, and that it killed more women than men, this excess being accounted for by the extreme frequency of cancer of the reproductive organs and by the larger number of women in the population “It has long been observed clinically,’' said Professor Bell, “that any form of chronic irritation may almost immediately, or more remotely, to cancer in the part affected. This means, in terms of our hypothesis, that all forms of chronic irritation, whether by extrinsic irritants, for example, radiations, heat, direct frauma, infection, certain chemicals, and the rest, or intrinsic factors, life toxfonrias and senescence, may lead to a common precancerons condition, wherein oxygen respiration is reduced. I would lay stress on the fact that the irritant factors, however different in themselves, or in their immediate actions, produce a common pre-cancerous state of asphyxia, on which malignant disease is liable to supervene; consequently the term ‘carcinogenic ’■ often applied to these agents is only indirectly applicable.” A PREVENTIVE SYSTEM. The first step in the prevention of cancer on a wide scale was to enlist the lay public in a vast co-operative scheme. He did not moan to suggest that once a year there .should be a “cancer week,” as in America, when the Press was flooded with articles mi cancer and the consulting rooms with terrified patients—in the excellent process of being frightened to life, as Moynihan put it. Rather would he demand a sustained effort, as habitual and as practically preventive as the washing of hands throughout the daily life of the individual. Prevention was concerned first with the avoidance or removal of those agents that were known to lead to tho precancerous condition, and, secondly, with the recognition and treatment of the precancerons slate before cancer developed. There were trades in which there was a particular tendency to certain types of cancer. They had a good illustration in the chimney sweeps’ cancer of the almost complete disappearance of a form of the disease after the recognition of the predisposing cause. No doubt mule-,spinners’ cancer and aniline dye workers’ cancer of the bladder would also soon coaso to exist. But, while the disappearance of industrial cancer would in no way improve flic serious general mortality rate, what happened when precautions were taken afforded a definite indication of the possibility of the prevention of the malignant disease supervening. It did not seem possible that cancer of the lips, mouth, tonsils, pharynx, and oesophagus, which was_ so much more frequent in men than in women, could bo due to anything hut bad habits and other avoidable factors such as alcoholism and syphilis. "With regard to habits, smoking played a largo part in the production of a precancerous state.

SMOKING ANJ) ORAL HYGIENE. Clay-pipe smoking, by the irritation of the hot stem, had long been known to be a primary factor in the causation of many cases of epithelioma of the lip. The clay pipe had gone out of fashion to a large extent, but, on the other hand, wooden-pipe smoking and the use of cigarette holders were probably on the increase. It was not the stem in these receptacles that was at fault, consequently they were not responsible for lip cancer; but they were gripped in tho most conilortablc position between the. teeth, and a stream of hot gases might ho directed always on the same part of the tongue, tho roof of the mouth, or the throat. The cigarette smoked in excess had other disadvantages. 11 a holder were not used it was the safest form of smoking, from the point of view under discussion, lor those who could not afford or did not like cigars. As to oral hygiene, generally speaking, a woman’s month was in a far better condition than that of many a man. A woman, naturally sensitive about her appearance, did not keep in her mouth jagged teeth that irritated the tongue and buccal mucosa; she had such deformities removed wholesale and replaced by a useful plate. With bad teeth there was nearly always oral sepsis. There was, therefore, two sources of irritation present m these circumstances. Again, syphilitic leukoplakia of the tongue—a precursor of cancer —was more common in men than in women. Cancer of the buccal cavity was non more common as a cause of death in men over forty years of ago than m women of a corresponding age period, in tho proportion of about five to one, and cancer of the oesophagus, too, nas fatallv more common in men than in women, in the proportion of about three to one. .Here agam a might be found m the coarsei (in the structural sense) lood males, as ‘ rule, preferred. burthcr, there •- little doubt that men,, in tho rush of work, tended to masticate then food imperfectly. Whether men drank then vvomen thci-e was S V Vn b s Ut saS ated with cancer of the (esophagus. THE INTERNAL PROBLEM. With regard to malignant disease of the stomach and ? t t greatly handicapped by the that owing to the vagueness of the »mp toms and the inaccessibility parts we rarely saw cancer ii > y stage. We did know, howevei, that the disease arose almost exclusively a certain points where, owing to structural conditions, delay was hable to occur-the outlet of the stomach, the caecum, and the rectum, with ™ • * patic and splenic flexures of the colon. Tho small intestine, in which the contents move rapidly onwards, was but rarely affected. . “]'s this state of affairs preventable!'” asked Professor Bell. Certainly it may be, if the condition is recognised early enough. Every lorni of indigestion and constipation reepnies far more attention than is usually devoted to the subject. The trouble may

be due to diet, debility, want of exercise, or irregular habits, all of which can be remedied. In the case of carcinoma of the stomach much discussion has taken place of recent years concerning the frequency with which simple ulceration is followed by malignancy of the part. I cannot help feeling that the modern surgical practice of excising simple ulcers has much to recommend it.” Passing to a consideration of cancer of tho female reproductive organs, in which he included the breasts, Professor Bell said there seemed to be certain advantages in that examination was easy, and that definitely precancerous states could be recognised. With >egard to cancer of the cervix uteri, in this country only 2 per cent, of all cases occurred in iiufliparous women, and the limitation of frequency occurrence to parous women was conclusive evidence of the predisposing factors, and some recent statistics furnished by Dr W. P. Graves seemed to show that the disease could ho almost abolished by surgical attention to the cervix. “It is not by preaching the wellknown value of treatment in early stages of cancer, which often escape tho trained surgeon himself, let alone the attention of the patient, ihat we shall best serve humanity,” said Professor Bell in conclusion, “ hut by preaching the certainty of die possibility of avoiding and curing ha precancerous state. "To do this wo must not only inform the public by inspired, educative articles in the lay Press, but also we must ■ institute all over the country clinics, private and public, to which everyone—at any rate, at first all at or past the age of lorty—mast go for biannual examinations. Side by side with an organisation of clinics on these lines, like ante-natal clinics, will go routine hospital practice designed to anticipate the disease. In this tno physician, surgeon, gyiuoologist, laryngologist, dentist, and others will al 1 play a prominent part.”