[Five patients with intrapulmonary lymph nodes indistinguishable from small peripheral carcinoma of the lung]

We encountered 5 patients with subpleural intrapulmonary lymph nodes. In all 5 patients, computed tomographic (CT) scans demonstrated subpleural small nodules in the middle or lower lung lobes. Because lung cancer could not be ruled out, biopsies by video-assisted thoracic surgery (VATS) were performed, yielding a diagnosis of intrapulmonary lymph nodes in all 5 cases. Two of the patients were women and nonsmokers. Sharply defined borders and subpleural locations were the characteristic CT findings for the intrapulmonary lymph nodes. However the borders of some of the nodules were irregular. Small peripheral lung cancer is also sometimes characterized by sharply defined borders and subpleural locations. For this reason, it is difficult to differentiate between intrapulmonary lymph nodes and small peripheral lung cancer on the basis of CT findings alone. VATS should be readily employed for diagnostic purposes in such cases.