CAUSES OF CANCER.

Otago Daily Times, Issue 20319, 30 January 1928, Page 8

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 ot certain precautions, we can relegate this dreadful disease to the obscure regions to which typhus fever, for example, has been banished. I want rather, it 1 can. to bring before you certain facts anfl certain suggestions based on those lacts 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 gynaecology in the University of Liverpool and director ol the Liverpool Medical Reseach Organisation introduced a lecture at the Institute ot Public Health, London, on “The prevention of cancer,” the term cancer being used synonymously with malignant disease,” “ malignant neoplasia/* and including “ sarcoma,” states the Manchester Guardian. Lord Dawson of Penn presi ced Such a statement, said Professor Bell, was not a confession of failure, but was indictaive rather of the mentality produced by the frequent sight of cases beyond all possibility of cure —cases in which the disease might never have occurred it the simplest of preventive measures had been adopted, or which might have been cured if seen at an earlier date. Hence, while as a second line of defence treatment at the commencement of the disease should be earnestly advocated, the first line of dtefeuce always will be prevention. The fact cannot be overlooked that, n prevention were carried out on the public health lines to be suggested, machinery would be brought i«to 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 yeavs hence nations would not be fighting one 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 1,000,000 perrons living in England and wales: 1847-1850 274 1851-185.3 306 1856-1860 :? 27 1801-1805 1866-1870 403 1871-1875 440 1876-1880 .. .. -• 494 1881-1885 548 1886-1800 532 1891-1895 712 1896-1900 800 1901-1905 - •• 86 < 1906-1910 539 1911-1915* 1053 1910-1920* HB2 1921-1925 1269 1926 1302 * Civil population only. In 80 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 1016 and 1926 were recorded as being due to malignant disease are shown in the following table: — 1916. 1920. Estimated total population . . 36,480,000 39,069,000 Death from all causes .. .. 508,217 453,804 Death from cancer 40,630 53,220 From these figures it was clear that in 1910 of all deaths'from birth upwards one in every twelve was due to cancer, and in 1926 one in every eight deaths. In 1920, between the ages of 40 and 50 years one in every six deaths was due to cancer, and between the ages of 50 and 70 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 2448 occurred in persons under the age of 40 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 40 years this might be dependent on the greater number of women in the population. In the age periods under 40 years in 1926 five females to every three males died of the disease, namely, 1551 females and 897 males. Sexpredilection 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 the intestines, including tho rectum, were most frequently affected. In males, out of 24,002 deaths from cancer 10,730 were due to disease in the organs mentioned, and, in females, out of a total of 27,937 deaths from malignant disease' 9857 occurred in those 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, ancl oesoohagus numbered 4622, in females cancer at these sites caused only 1032 deaths From the statistics quoted we gleaned that malignant disease was very rare still —in spite of individual impressions—before the age of 40 years, and that it killed more women than men, this excess being accounted for by tho extreme frequency of cancer of tho reproductive organs and by the larger number of women in the population. , •* It has long been observed clinically, said Professor 8011, “that any form of chronic irritation may almost immediately, or more remotely, lead to cancer in tho part affected. This means, in terms of our hypothesis that all forms of chrome irritation, whether by extrinsic irritants, for example, radiations, heat, direct trauma, infection, certain chemicals, and the rest, or intrinsic factors, life taxaemias and senescence, may lead to a common precancerous condition, where in oxygen respiration is reduced. X would lay stress on the fact that the irritant factors, however different in themselves, or in their immediate actions, produce a common procancerous state of sphyxia, on which malignant disease is liable to supervene; consequently the term “carcinogenic” often applied to there 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 xu vafiti co-operative scheme, tie did not mean to suggest that onto a year there should be a “ cancer week, as m America, when the press was flooded with articles on cancer and the consulting rooms with terrified patients—in the excellent process of being ilightened to life, as Moyuihan puts it Rather would he demand a sustained effort, as habitual and as practically preventative as the wshng ofoot ticallv preventative as the washing of hands throughout the daily life of tho individual. I'lcvonliou was concerned first with the avoidance or removal of those agents that were know to lead to the preoancerous condition, and, secondly, with the recognition and treatment of the precancerous state before cancer developed. There were tiados in which there was a particular tendency to certain types of ( juicer. They had a good illustration in tho chimney sweeps’ cancer of the almost complete disappearance of a form ot the disease after tho recognition of the predisposing cause. No doubt niulc-spm-uers’ -aueer and aniline, dye-workers’ canc„r 0 f the bladder would also soon cease to exist. But. while tho disappearance ot industrial cancer would in no way improve the serious general mortality rate, what happened when precautions were taken afforded a definite indication of the possibility of the prevention of malignant disease supervening., . . It did not seem possible that cancer of the lips, mouth. tonsils, pharynx, and oesophagus, which was so much more frequent iii men than in women, could bo due to anything but bad habits and other avoidable factors such as alcoholism and syphilis. -With regard to habits, smoking played a large part in the production ol a precanccroua state.

SMOKING AND 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 hanj, woodenpipe 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 the most comfortable position between the teeth, and a stream of hot gases might be directed always on the same part of the tongue, the roof of the mouth, or the throat. The cigarette smoked in excess had other disadvantages, if a holder were not used it was the safest form of smoking, from the point of view under, discussion, for those who could not afford or did not like cigars. As to oral hygiene, generally speaking, a woman’s mouth 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 were, therefore, two sources of irritation present in 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 now more common as a cause of death in men over 40 years of age than in women of a corresponding age period, in the proportion of about five to one; and cancer of the oesophagus, too, was fatally more common in men than in women, in the proportion of about three to one. Here again a reason might be found in the coarser (in the structural sense) food males, as a rule, preferred. Further, there was little doubt that men, in the rush of work, tended to masticate their food imperfectly. Whether men drank their tea, coffee, and soups when at a higher temperature than those consumed by women, there was no direct evidence to show, but it was likely. Alcoholism, too, was said to be frequently associated with cancer of the oesophagus. THE INTERNAL PROBLEM. With regard to malignant disease of the stomach and intestines we ■ ere greatly handicapped by the fact that owing to the vagueness of the symptoms and the inaccessibility of the parts we rarely saw cancer in an early stage. We did know, however, that the disease arose almost exclusively at certain points where, owing to structural conditions, delay was liable to occur—the outlet of the stomach, the caecum, and the rectum, with the hepatic and splenic flexures of the colon. The small intestine, in which the contents move rapidly inwards was but rarely affected. “ Is this state of affairs preventable? ” asked Professor Bell. “ Certainly it may be, if the condition is recognised early enough. Every form of indigestion and constipation requires 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 the female reproductive organs, in which he included the breasts, Professor Bell said' there seemed to be certain advantages in that examination was easy, «nd that definitely precancerous states could be recognised. With regard to cancer of the cervix uteri, in this country only 2 per cent, of all cases occurred in nuliparous women, and the limitation of frequency of 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 be almost abolished by surgical attention to the cervix. “ It is not by preaching the well-known value of treatment in early stages of cancer, which often escape the trained surgeon himself, let alone the attention of the patient, that we shall best serve humanity,’’ said Professor Bell, in conclusion, “ but by preaching the certainty of the possibility of avoiding and curing the precancerous state. To do this we 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, nil at or past the age of 40—must 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 the physician, surgeon, gynaecologist, laryngologist, dentist, and others will all play a- prominent part.’’