PLEURAL SIGNS OF SMALL PERIPHERAL PULMONARY MASSES - PATHOLOGICAL CORRELATION WITH CHEST RADIOGRAPHS AND DIAGNOSTIC-VALUE

Objective: The current interest in 'cost-effectiveness' of medical ima gings means that chest radiography is the primary radiological examina tion of lung diseases. We attempted to investigate the pathological ba sis of different pleural signs, and determine their usefulness in diff erentiating small bronchogenic carcinomas from tuberculomas by using c hest radiographs. Materials and methods: We prospectively studied 30 s mall solitary pulmonary masses, including 24 carcinomas and 6 tubercul omas. All 30 resected lobe specimens were investigated with preoperati ve radiographs, postoperative specimen radiographs, 10-15 mu m thick w hole-mount sections, and 5 mu m thick slices for conventional histolog ical examination. To evaluate the clinical usefulness of these pleural signs, we also retrospectively reviewed 100 chest radiographs and con ventional tomographs of 1-3 cm peripheral pulmonary lesions, including 60 bronchogenic carcinomas and 40 tuberculomas. Results: The results confirmed that, besides the previously known interlobular septal fibro sis with pleural retraction, the pathologic basis also included the pl eural puckering and adhesion with fluid collection for the 'tail' and 'rabbit ears' signs, and pleural dimpling with fluid collection and pe ripheral fibrous hyperplasia for the 'triangular shadow' signs. In the retrospective group, the pleural signs with adjacent pleural thickeni ng was significantly more frequent in tuberculomas than in carcinomas (P < 0.05, chi(2)-test). Conclusion: Pleural signs associated with adj acent pleural thickening seems to contribute to differentiating granul omas from carcinomas. The pathological basis for this radiological fin ding includes visceral pleural fibrosis with the inflammatory cell inf iltration, and the wide and shallow pleural dimpling filled with react ive pleural fluid. (C) 1997 Elsevier Science Ltd.