Round atelectasis and Metsovo lung.

Round (helical) atelectasis is one of the benign sequelae of occupational asbestos exposure. Environmental asbestos exposure does not differ from occupational in its pleural manifestations, but to our knowledge, round atelectasis has not been reported yet. In the present study, we present the clinical and radiologic findings of five individuals with round atelectasis. They were all born in the Metsovo area, northwest Greece, where environmental exposure to asbestos (tremolite) has been documented. All five had negative evaluation for malignancy. In addition, they have been followed up for one to four years and four of them are in good health, thus confirming round atelectasis as a benign, nonpremalignant condition. The fifth patient died of malignant pleural mesothelioma two years later, while the previously detected round atelectasis remained unchanged. We therefore consider that his mesothelioma was not related to the round atelectasis, although both were certainly related to the same environmental asbestos exposure.