Saturday Morning, April 15, 1950

9:00 A.M. Business Meeting.

9:30 A.M. Scientific Session.

1. Intrathoracic Neurogenic Tumors.

J. T. Godwin, M.D. (by invitation), W. L. Watson, M.D.

J. Pool, M.D., and W. Cahan (by invitation)

New York, N. Y.

Twenty-one cases of intrathoracic tumors of nerve origin are presented from the Memorial Hospital. The pathology is organized in terms of a simple classification consonant with recent terminology and present knowledge of the life history of these tumors. Special emphasis is laid on clues to malignancy.

The clinical features are presented to emphasize differential diagnosis and characteristic radiographic signs. The special features of operative treatment are discussed.

2. Tumors of the Thymus.

W. D. Seybold, M.D., John R. McDonald, M.D.,

O. T. Clagett, M.D., and G. A. Good, M.D. (by invitation)

Rochester, Minn.

Tumors of the thymus have been the object of much attention from pathologists, clinicians and surgeons since Weigert in 1901 described a case of myasthenia gravis in which a thymic tumor was found at autopsy. This association of myasthenia gravis with tumor of the thymus has been confirmed subsequently by many observers. However, the relationship between them is no more clear now than it was at the time of Weigert's report. Furthermore, there are other features of thymic tumors that are of uncommon interest. Only a small number of patients with myasthenia gravis have thymic tumors. Removal of the tumor has no uniformly beneficial effect on the course of the disease. The rarity of the tumors and the lymphoid character of the thymus have made differentiation of tumors arising from it and other tumors of the anterior mediastinum most difficult. Many tumors arising in the anterior mediastinum have been classified, probably erroneously, as thymic in origin. While the histologic distinction between a thymic tumor and a lymphosarcoma of the anterior mediastinum may be difficult or impossible, the response of each to exposure to deep roentgen rays is usually quite different. Not all tumors of thymic origin are associated with myasthenia gravis. While thymomas in patients with myasthenia gravis fall into a distinct histologic pattern, this same pattern has been seen in a number of thymomas in patients who had no evidence of myasthenia. Most thymomas are encapsulated and can be shelled out readily from their bed in the mediastinum, but many are found at operation or necropsy to have invaded the pleura, pericardium and great vessels. Constant histologic differences between the encapsulated and invasive varieties have not been found to exist. Whereas deposits of calcium are extremely rare in malignant tumors generally with the exception of those which arise from bone, they are common in thymomas, in both the encapsulated and unencapsulated varieties. Thymomas that have been found to have invaded adjacent vital structures and to be ineradicable are compatible with long survival and freedom from disabling symptoms.

Forty-five cases in which the diagnosis of thymic tumor was verified by tissue removed at operation or at necropsy form the basis of this report on the clinical, pathologic and surgical aspects of the lesion.

3. Treatment of Carcinoma of the Lung Associated with Malignant Tumors Primary in Other Sites: Report of Eight Cases.

William G. Cahan, M.D. (by invitation),

Frank S. Butler, M.D. (by invitation),

William L. Watson, M.D. and John L. Pool, M.D.

New York, N. Y.

Within the past year at the Memorial Hospital there have been eight cases with a proved malignant tumor primary in a site other Than the lung, and associated with bronchogenic carcinoma. Six of these separate primaries were capable of metastasizing. In these cases the appearance of a solitary lung density was found by routine chest roentgenogram. Exploratory thoracotomy showed them to be carcinoma primary in the lung and in a favorable location for resection.

The anatomical sites that were associated with the lung neoplasms include the hard palate, intrinsic, larynx, buccal mucosa, breast, colon and breast (triple primary) and rectum. Two other cases were basal cell skin cancers.

In a study of 1,500 cases of lung carcinoma, there were 25 other primary malignant tumors associated with a primary malignant lung tumor.

4. The Surgical Management of Carcinoma of the Lung.

E. D. Churchill, M.D., R. H. Sweet, M.D.,

L. Soutter, M.D. and J. G. Scannell, M.D.

Boston, Mass.

A parallel study of the results achieved by pneumonectomy and lobectomy for primary carcinoma of the lung at the Massachusetts General Hospital over the period 1934 to 1948 is presented. The value of resection is evaluated in terms of survival of the patient, operative mortality and immediate or long-term morbidity. Since lobectomy was performed by choice in a significant proportion of the resected cases, a basis for comparison of the efficacy of the two procedures is provided.

5. A Study of Pulmonary Hemodynamics During Pneumonectomy.

Harvey J. Mendelsohn, M.D., Henry A. Zimmerman, M.D.

and Arthur Adelman, M.D. (by invitation)

Cleveland, Ohio

Pulmonary hemodynamics have been studied before and after pulmonary resection in humans but, to our knowledge, these are the first observations of changes occurring during the actual operative procedure. To date eight patients have been studied, six patients undergoing pneumonectomies, one undergoing lobectomy and one during an exploratory thoracotomy. One hour preoperatively, a Cournand catheter was introduced into an anticubital vein and under fluoro-scopic control placed in the pulmonary artery opposite to the one to be ligated. Basal cardiac outputs were determined by the Pick principle and initial pressures were recorded. The electrocardiogram, phase of respiration and femoral or brachial arterial pressures were recorded simultaneously, on a six channel direct writing oscilograph. Subsequent observations were made at 15-minute intervals throughout the entire procedure, including the immediate period of ligation and after the closure of the chest. In two patients, whose lesions were not resectable, the pulmonary arterial pressure measurements were obtained after temporary ligation of one pulmonary artery.

In one additional patient left auricular pressures were determined by inserting a catheter into the left auricle through a tributary of the superior pulmonary vein of the lung to be resected. In another patient left intraventricular electrocardiograms were taken by this same method.

The following changes were observed: There was a rise during the induction of anesthesia of both systolic and diastolic pulmonary artery pressures, averaging as high as 70% in the diastolic and 36% in the systolic pressures. The increase in systolic pressure during ligation ranged from 18% to 70%, the average being 40%. In three cases a decrease in diastolic pressure was observed and in the rest a moderate increase was observed. There was a slightly greater change in pressure, as a rule, when the right pulmonary artery was ligated. Pressures returned to pre-ligation levels in most cases by the end of the procedure.

One patient who had a high pulmonary artery pressure developed congestive heart failure and an increase in his pulmonary artery pressure after left upper lobectomy. It was thought that determination of pulmonary arterial pressures preoperatively might help to detect unsuitable risks for pulmonary resection, particularly in those patients with initially high pulmonary artery pressures.

Studies are continuing and further information will be available as the studies go on.