Carcinoid of the bronchus.

During the last 15 years I have had occasion to observe 54 cases of benign lung tumors. During the same period of time 1462 cases of malignant tumors were observed; the percentage of benign tumors represents 3.7%. If among the benign tumors we distinguish between those of epithelial and those of connective nature, the per cent drops to 2.1, which indicates the frequency of appearance of epithelial benign tumors compared to the malignant ones. As far as the connective type is concerned, the frequency of benign tumors in comparison to malignant ones amounts to 59 per cent, taking into account the rareness of malignant connective lung tumors. Of the 54 cases of lung tumors mentioned in the beginning, 32 were epithelial and 22 connective. From the histologic point of view, the 32 tumors of epithelial nature can be divided into papillomas and adenomas; of the former we have observed two cases, of the latter 27 can be defined as carcinoids, two as cylindromas and one as muco-epidermoid tumor. The connective tumors can be classified as fibromas (one case) and lipomas (4 cases), two of these being endobronchial. Three cases can be defined as "condromas", two of which are endobronchial. Finally, 14 cases are classified as „amartomas"; 3 of these were vascular and 11 cartilagenous, one of these being endobronchial. I shall deal in particular with the epithelial benign tumors. Also in my cases, as in most of the observations made, it is clear that the right lung is more often involved than the left. In fact, in 21 cases the tumor was localized in the right, and in 9 cases in the left lung. There is no difference as far as the sex is concerned. In the great majority of the cases, the carcinoid is located in the main bronchi, and more frequently in the lobar bronchi. The tumors which are found in the trachea or in the smaller bronchi, are in great minority. From the macroscopic point of view, they can be classified as endobronchial forms, free or extra-bronchial or "iceberg" tumors, and 'roundlike' or peripheral forms. The most frequent ones are the endobronchial forms. They can be sessile, pedunculated or ramified. In this latter case they appear as pseudo-polypoid masses in ovoid or ramified form of variable consistence, with a smooth and generally bright and shiny surface. The color depends on the density of vascularization. The ramifications extend to the peripheral bronchi, filling them and reproducing the form. The "iceberg" tumors observed by us had the characteristic disposition of a small endobronchial and a larger extrabronchial portion, always clearly separable the pulmonary parenchyma, although it lacks a real limiting capsule. The small, ball-like forms, which are parenchymatous may serve as example of the so-called "solitary nodule" of the lung. From the histologic viewpoint after the studies of FEYRTER and those of FLAMMIA, PICARDI and Pozzi , I see no longer any reason to differenciate intestinal and bronchial carcinoids. On