Endothelioma of the Pleura: Clinical and Roentgenologic Study of Three Cases

Primary endothelioma of the pleura is usually regarded as a rare tumor. This belief is undoubtedly due, in part, to the lack of a clear-cut clinical syndrome and characteristic roentgen picture. Many patients are studied for considerable periods before the true pathological condition is recognized. The long-standing symptomatology may suggest a chronic inflammatory process and mislead the clinician as to the malignant character of the lesion. Metastasis is in most cases of late occurrence, although the primary growth is frequently multiple and widely distributed over the pleural surfaces. Some difference of opinion exists regarding the true nature of these pleural tumors. Writers of one group believe that they are always secondary to primary carcinoma of the lung or bronchus, while others hold that they develop from the endothelial cells of the lymph spaces or lining cells of the pleural surface. Clinical Findings The clinical picture in pleural endothelioma is usually inconclusive. In the earliest stage, when involvement of the pleura is slight, there may be few symptoms or none at all. Some patients complain of severe pleural pain and elevation of temperature. Stivelman (3) states that pain, as a rule, is intense and, unlike the pain of tuberculous pleurisy, is rarely relieved by development of an effusion. He also calls attention to a dry irritating cough. Banyai and Grill (1) believe that patients with early symptomless lung tumors may experience their first symptoms following influenza or some other infection, as a result of increasing bronchial stenosis. Dyspnea on exertion is common. When fluid develops, it simulates an inflammatory effusion, but malignant cells may sometimes be demonstrated microscopically in the aspirated fluid. Anemia is sometimes present but is of little aid in diagnosis. Fever of varying degree and regularity may occur and is probably of toxic origin. Wessler and Jaches (4) state that there is a marked contrast between the inordinate size of pleural tumors, especially the endotheliomata, and the paucity of symptoms which they produce. A patient with no symptoms other than some dyspnea and possibly fever may show extensive roentgen changes over one side of the chest. Roentgen Findings In the early stages of endothelioma of the pleura the roentgen examination usually discloses a diffuse clouding of the affected area suggesting a pleural reaction with or without fluid. This usually occupies the basal or axillary areas of the chest. It is not circumscribed and has no characteristic appearance. As the lesion continues to develop, the opacity of fluid becomes evident. When the fluid is withdrawn it reaccumulates rapidly and this fact may be the first suggestion of the presence of a neoplasm. In most instances the lung film fails to disclose the tumor nodules, although occasionally one or more may be seen above the fluid level.