Smooth muscle hyperplasia in an asthmatic patient: do we know it all?

Bronchial smooth muscle hyperplasia is a well-known structural change in asthma. The degree of hyperplasia is related to asthma severity. We report a case of extreme smooth muscle hyperplasia in an asthmatic patient. A 54-year-old female with a diagnosis of analgesic-induced asthma was admitted to our center for nasal polyposis surgery. During her preoperative evaluation, atelectasis of the right middle lobe was detected on chest X-ray. Bronchoscopy revealed the presence of a vegetating polypoid mass obliterating the entrance of the right middle lobe. Histopathological examination of the surgically excised polypoid mass showed benign smooth muscle proliferation with diffuse eosinophilic infiltration. This is a rare case representing an extreme example of benign smooth muscle hyperplasia forming an endobronchial mass in an asthmatic patient.