Rounded atelectasis of the lung, just a benign disorder.

Three patients with rounded atelectases are described. One of them developed a malignant non-Hodgkin lymphoma 6 months after presentation with rounded atelectasis. His rounded atelectasis could be followed during 20 months and was unrelated to the appearance, complete remission after chemotherapy and relapse of a malignant non-Hodgkin lymphoma. Rounded atelectasis of the lung is a little-known form of peripheral pulmonary collapse which may mimic a neoplastic tumour. It might be formed either because of a folding in a basal lung segment caused by temporarily pleural effusion, or because of initial damage to the pleura which leads to fibrosis and thus to challenge to the clinician, it should be emphasized that the benign nature of rounded atelectasis should be recognized by radiological techniques.