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and the cures actually being accomplished is one of the unique features of cancer and one which forms the basis of the program for its control.
While, as has been said, “early diagnosis” is not synonymous with “curable," the principle, “the earlier, the better,” remains a cardinal precept in medical practice and in cancer control.
In aggregate, it is probable that about one-fourth of patients with cancer today, receiving proper medical care, are being cured. With the methods of treatment presently at hand, it is estimated that twice this number could be cured, provided the aforementioned optimal conditions could be achieved. In terms of actual numbers, this means that approximately 73,000 lives are being saved yearly and that an equal number now dying are potentially salvageable. The remaining doomed half of those destined to develop cancer must look to the advances of future research for their salvation (chart 9).
Recognizing the critical importance of time, or delay, in influencing the results of cancer treatment, a group of doctors in 1913 recommended the establishment of a voluntary organization whose objective it would be, among other things, to develop and carry on a broad program of public education. Specifically, the program would seek to inform the laity of the early warning signs of cancer and to make clear the importance of immediately heeding them. Today this program of public education continues and its basis is the Seven Danger Signals of Cancer (chart 10). Every medium of communication and public information is utilized in promulgating this information: Printed pamphlets, motion pictures, radio, television, exhibits, window displays, billboard posters, car and bus cards, bulletin-board handbills, special mailings, and talks by properly qualified persons to groups and assemblies of many kinds, such as women's clubs, parent-teacher associations, church guilds, industrial groups, and mass public meetings.
Recent studies offer evidence that this 40-year-old effort in health education of the public has borne fruit. Virtually every study of the trend of the factor of delay for which the patient is responsible has shown a consistent lowering in the element of delay. To put it another way, more patients are being seen with earlier cancer than ever before (charts 11, 12, and 13). These findings are substantiated by the experience of most practicing physicians who have commented on this facet of the problem.
The increasing consciousness of cancer on the part of the public has imposed added burdens on the medical profession, for it is a fact that the earlier the cancer, the more difficult it is of diagnosis. Therefore, in order to assist doctors to maintain a high index of suspicion paralleling that of the public, the American Cancer Society conducts its national office and affiliated divisions an intensive program of profession education (chart 14).
Through publications, library reference services, the monthly index of current cancer literature, through motion-picture films produced in cooperation with the National Cancer Institute, through refresher courses, and now through the medium of closed circuit color television, the society endeavors to bring to the practicing physician, already overburdened by an avalanche of new medical information, the facts about cancer which will facilitate his handling of the clinical problems which it presents in office practice.
Eighty-eight clinical fellowships awarded annually permit young physicians to obtain additional training in the diagnosis and treatment of cancer in its special forms; and 15 fellowships in exfoliative cytology or smear diagnosis permit qualified pathologists to spend varying periods up to a year in acquiring proficiency in this new and extremely useful diagnostic technique. In addition, fellowships are available to permit young physicians who have already obtained in the United States extensive training in radiation therapy to go abroad to study for a period of 1 year at selected radiation therapy centers in the Scandinavian countries, the United Kingdom, and France. Every 3 years, the American Cancer Society joins with the National Cancer Institute and the American Association for Cancer Research in conducting a National Cancer Conference, in which clinical and research aspects of cancer are reviewed and progress evaluated.
DETECTION OR CASE FINDING
But useful as the danger signals have been and will continue to be, experience demonstrated (1) that all too often the apperance of a danger signal was, in fact, a manifestation of moderately advanced disease, and (2) that it was frequently possible to discover cancer—"silent" cancer—in patients who had no signs nor symptoms of disease. This was, in effect, discovering cancer before it had given rise to gross expressions of its presence. The effort to find cancer in nonsymptomatic patients was begun on a formal scale in 1937 and initially it was confined to the search for cancer of the uterus. When it had been shown that truly early and curable cancers could be found in patients in advance of symptoms, the practice was taken up by others and extended to other body sites. There are today some 240 cancer detection centers in the United States (chart 15), which operate for the most part in the environment of a hospital clinic and which endeavor to confine their activity to the search for cancer and other diseases in presumably well persons. More recently, medical societies in a number of States have endeavored to have this practice of cancer detection adopted as a formal regime oriented to office practice and it can safely be said that these routine physical checkups, so important in the maintenance of health, particularly in older persons, are more widely sought than ever before. Nevertheless, only a small fraction of the population submits to such regular examination.
In an analysis of the effectiveness of this type of preventive medicine-preventive in the sense of preventing deaths—the American Cancer Society studied the cancer yield in some 52,000 examinations conducted in 90 detection centers. It was found that the rate of cancer for the entire group of examinees unselected as to age was eight per thousand. The rate of cancer discovered varied from 1.2 cases per thousand for the group under 30 years of age, to 34.3 per thousand in the group aged 60 and beyond, with, as was to be expected, a progressive rise in the cancer yield with advancing years. These facts suggest that, while it may be impractical and, indeed, impossible, to examine the entire population for evidence of cancer or other disease on a regular schedule, nevertheless an approach to effective chronic disease prophylaxis might be achieved through the establishment of such screening devices as selection according to age. Thus, it seems poor economy to attempt to find cancer under the age of 40. It appears distinctly worthwhile to do so in persons beyond the age of 50 (chart 16).
SERVICES OF THE AMERICAN CANCER SOCIETY
Approximately two-thirds of the cancer detection centers referred to above have been supported in some measure by field units of the American Cancer Society. Other services subsidized or provided by the society in an effort to improve the quality of cancer service in the United States include financial assistance to cancer clinics and cancer diagnostic clinics, previously referred to (chart 17). The society also maintains information services in most of the major cities and in many of the smaller communities. The society supports local visiting nurse associations in order to increase the quantity and quality of nursing care to patients confined to the home; in addition it is the society's policy to provide, where needed, practical nursing service and housekeeping assistance. Many units of the society, further, provide drugs to indigent patients for whom the purchase of vitamins, hormones, and narcotics is burdensome, if not impossible. The society's volunteer arm provides transportation for patients going to and from the hospital or doctor's office, unlimited dressings for those needing them, maintains loan closets where some 240 items of sickroom necessity or convenience are stocked and available without cost, recreational therapy programs for patients confined to home or hospital and a home visiting service (chart 18).
Evidence at hand indicates that, whereas there does not appear to be any significant difference in susceptibility to cancer in general in different parts of the world, there is noted a predeliction for certain kinds of cancer in certain areas or among certain ethnic groups. Study of the geographic distribution of cancer according to its type and site is now recognized as a respectable enterprise and the American Cancer Society and the National Cancer Institute are engaged in various studies in an effort to elucidate the pattern of incidence of cancer and to derive therefrom, if possible, helpful, even important, suggestions as to cancer's causes.
Such epidemiologic studies form an important segment of the statistical research section of the national office of the American Cancer Society. For example, collation of information from various sources discloses the fact that cancer of the skin is significantly more common in the South and South Central States of the United States than it is in the Northwest or Northeast (chart 19). It has long been suspected that solar radiation can, in proper amounts and over sufficiently long periods of time, favor the development of skin cancer, a surmise now supportable by laboratory experiment. It appears obvious that the increased prevalence of cancer of the skin in the regions cited, is attributable to the increased occupational and recreational exposure of the inhabitants to strong rays of the sun. Of course, not all people so exposed do actually develop cancer of the skin, so that one must conclude that there is a factor of individual susceptibility operating also. Other curious differences in the attack rates of cancer, site by site, are apparent within the United States. Thus, cancer of the uterus appears with as great frequency in the South as it does in the Northeast, whereas cancer of the breast appears to be distinctly less common in the Southern belt (charts 20 and 21). These curious differences have invited much speculation and it is probable that among the reasons already advanced for certain of these differences some will prove to be substantiable. Among the other activities of the statistical research section (chart 22) of the society is a study, now going forward, of the possible relationship between smoking practices and the incidence of cancer of the lung. The section has, in cooperation with the National Institutes of Health of the United States Public Health Service, devised a standard method for cancer-reporting on a statewide basis, and this system, or modifications of it, are gradually being adopted.
TRENDS : AN EVALUATION OF EFFECTIVENESS Scattered and early returns from a number of sources support the validity of the program of cancer control described. If there is any virtue in reducing the delay before treatment, in improving facilities for diagnosis and treatment, in increasing professional educational opportunity, in stimulating case finding—it should be apparent in improved or lengthened survivorship.
In 1937 a study, based on all cancer patients admitted to hospitals in Vermont, yielded the fact that only 20 percent of the group had localized disease and were considered candidates for curative treatment. A study in the same State 10 years later indicated that the percentage of cancer patients admitted to Vermont rospitals with localized disease had risen to 58 (chart 23).
Among breast cancer patients seen in the Mayo Clinic between the years 1910 and 1919, 63.6 percent were found to have involvement of axillary lymph nodes ; that is, cancer had spread from the organ of origin to the neighboring lymph glands--a relatively unfavorable setting for cure. Of the breast cancer patients seen in the same clinic in the year 1945, the proportion with axillary nodal involvement had dropped to 45 percent (chart 24). These figures are reflected in the steadily increasing cure rates reported from that clinic: of all patients with breast cancer operated on in the period 1910 to 1914, 39.7 percent were living 5 years later; of the patients operated on during the period 1940 to 1944, 62.4 percent were living 5 years later. This experience is confirmed by that in the Memorial Hospital, New York (chart 25).
Dublin has analyzed the cancer death rate among female policyholders of the Metropolitan Life Insurance Co. and has found a 11-percent decline in the total cancer death rate during the decade 1938-48 (chart 26). In the age group 55 to 64, where cancer is noted with greater frequency, the percentage decline amounted to 15.1.
In the statewide cancer registry of Connecticut, as analyzed by E. J. McDonald, steadily increasing survivorship rates were recorded in the interval of study 1935–41 (charts 27, 28, and 29). Of the males with cancer in the State of Connecticut, who were registered in 1935, 18 percent were living 5 years later, while of those registered in 1941, 25.7 percent passed the 5-year mark. Of the females with cancer registered in 1935, one-quarter were alive 5 years later, while of those registered in 1941, approximately 40 percent were alive at the end of the 5-year period. For males and females combined, 5-year survivorship rose from 22.1 percent of the group initially recorded in 1935 to 33.5 percent of those admitted to the registry in 1941.
The figures for the United States, based on death rates analyzed by site between the years 1933–46 and standardized for age, discloses that slight increases, some of questionable statistical significance, are noted for cancer of the prostate, intestines, larynx, ovary, and pancreas. Of unquestionable statistical importance is the increase noted in cancer of the lung for both males and females. No increase or an actual decrease is noted for cancers of the oral cavity, esophagus, lip, skin, breast, bladder, kidney, stomach, uterus, and rectum (charts 30, 31, 32, 33, 34, and 35).
It would appear that most forms of cancer are susceptible of control to a degree and are being influenced favorably, although not as fast as we would like, and not to the extent possible. Certainly many would agree with the observation that there is no major health problem facing the people of our country which is characterized by so striking a disparity between relief which appears possible with the knowledge and skills now at hand and that actually being achieved. That the mechanism for realizing the potentials for cancer control has been established and that it has demonstrated its soundness may be fairly inferred from the evidence at hand.
DEATH RATES *OF SELECTED DISEASES
United States, 1900-1950