The significance of cell types in bronchogenic carcinoma.

Abstract

Physicians dealing with diseases of the thorax have long been aware that carcinoma of the lung varies greatly in its clinical manifestations, and that certain types of bronchogenic carcinoma are much more amenable to surgical eradication than others. The great frequency with which bronchogenic carcinoma occurs and its apparent increasing incidence make it essential to determine as far as possible the various factors that may influence the course of the disease. In discussing bronchogenic carcinoma, it is first essential to define what Is included by the term. Bronchogenic carcinoma is a primary carcinoma of the lung which is presumed to originate in the mucosa of the bronchi. Metastatic carcinoma of the lung, adenoma of the bronchus, and alveolar cell tumor must be distinguished from bronchogenic carcinoma, for not only are their clinical course and prognosis different from those of bronchogenic carcinoma, but they have an entirely different source of origin. The results of early studies that were carried out to classify carcinoma of the lung solely on the basis of grade of malignancy of the tumor according to the method of Broders were soon found to be of little or no clinical, surgical or prognostic value. It has long been recognized that true bronchogenic carcinoma may assume a variety of form’s, and many terms have been utilized by pathologists to describe these various changes. This lack of uniformity in terminology has made an understanding of the significance of cell types in carcinoma of the lung difficult. It Is only since sufficient surgical and necropsy material has become available that it is possible to study and correlate the clinical course of the disease with survival following operative intervention and to devise a workable histologic classifIcation. In order to study the problem of the significance of cell types of bronchogenic carcinoma, the records of 1,000 cases of proved carcinoma of the lung, taken at random from the files of the Mayo Clinic, were reviewed. In each case, the diagnosis of carcinoma of the lung was based on the examination of bronchoscopic specimens, specimens taken for biopsy at the time of thoracotomy for inoperable neoplasms, and surgical specimens obtained by lobectomy or pneumonectomy. This series did not include any case in which there was evidence of carcinoma elsewhere in the body or in which there was a chance that the pulmonary lesion might be metastatic. �Read at the Joint Session of the First International Congress of Bronchoesophagology and the Second International Congress on Diseases of the Chest of the American College of Chest Physicians, Rio de Janeiro, Brazil, August 24 to 30, 1952.