This section is from the book "Early Detection And Diagnosis Of Cancer", by Walter E. O'Donnell. Also available from Amazon: Early Detection And Diagnosis Of Cancer.
At the present time routine x-ray examination of the chest is the only method generally available for the detection of lung cancer in the asymptomatic individual, and even this has recently come under critical fire for reasons which will be discussed below. Cytologic examination of the sputum holds promise for the future as a screening device in selected high-risk groups; this also will be discussed below.
Not infrequently the physician will be confronted by a patient who has been labeled a lung cancer suspect because of x-ray findings encountered as a result of the application of this case-finding technique.
1. Films. Recommended for the detection of lung cancer is a photoroentgen (minifilm 70 mm.) or a standard 14 X 17 posteroanterior chest film taken at periodic intervals in those individuals in the high-risk groups. Usually this is done in one of the following settings:
(a) Office. The chest film is made as part of a routine complete "checkup."
(b) Survey. The individual participates in mass community survey (usually done for tuberculosis case-finding).
(c) Hospital admission. In keeping with hospital policy, chest films are routinely made on admission on a large proportion of the 25 million Americans hospitalized annually.
(d) Employment. Chest films are made as part of the standard pre-employment examination or annually as a result of medical department policy.
(e) Armed forces. Chest films are usually taken at the time of enlistment and discharge and often at intervals in between.
Much criticism has been leveled recently at the practice of routine periodic chest films-principally on the basis of radiation exposure, high cost, low yield, poor salvage rate of cases found, etc. With regard to community surveys, many of these points are well taken. However, at the level where the individual physician can select those individuals to be surveyed and undertake an aggressive program of follow-up, the routine chest film can play an important role in the early diagnosis of lung cancer. Also, it provides a good baseline for the evaluation of possible future abnormalities.
In summary, a routine chest film on all high-risk individuals at least once a year, with appropriate arrangements for careful interpretation and speedy follow-up, constitutes a reasonable program for the detection of lung cancer. In this case, high-risk individuals may be defined as those persons (male or female), 45 years of age or over, with a history of smoking a pack or more of cigarettes daily for at least twenty years. The occasional individual with a specific occupational exposure should, of course, be included also.
Random fluoroscopy of the asymptomatic individual as a method of lung cancer detection is mentioned only to condemn it. It should not be used for the following reasons:
1. Radiation exposure. This varies greatly according to the circumstances, but the amount of ionizing radiation to which both patient and doctor are exposed can be considerable-certainly far more than that involved in the single chest film.
2. Relative insensitivity. Even in highly experienced hands and under ideal circumstances, the very minute lesion one is searching for may be overlooked. When the examiner is one who does only occasional fluoroscopy, using equipment which may be substandard, and is unable to spare the fifteen minutes or more usually required to accommodate his eyes for optimum perception, what little justification there might have been no longer obtains.
3. Lack of permanent record. The unavailability of a film which can be studied and reviewed at leisure and compared with previous and subsequent ones is not the least of the drawbacks to fluoroscopy.
Fluoroscopy of the chest can make major and vital contribution in other situations. Its random use, however, as a means of detecting lung cancer in the apparently well individual must be condemned.
Until recently, cytologic examination of the exfoliated cells from the tracheobronchial tree had not been proposed as a screening device for the detection of lung cancer. Lack of adequate facilities and personnel has been a major deterrent. The principal stumbling block, however, has been the simple fact that most asymptomatic (and, in fact, many symptomatic) individuals cannot produce satisfactory sputum specimens. The picture with regard to facilities and personnel, however, is improving, and recently a new relatively simple provocative aerosol technique has been introduced which makes it possible to obtain an adequate specimen from nearly anyone. This has important implications in the case of those presenting a difficult differential diagnostic problem and will be discussed in detail below. Furthermore, it would seem to bring the day much closer when high-risk groups can be surveyed cytologically for the presence of occult lung cancer or its precursor states. The technique of sputum collection (see p. 130) is relatively uncomplicated and can be carried out in the physician's office.
 
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