Primary pulmonary pleomorphic adenoma with cryptogenic organising pneumonia – A rare entity

Abstract

Abstract Pleomorphic adenoma, a common salivary gland tumor of the head and neck is a rare occurrence in the lung. We report a case of Primary pulmonary pleomorphic adenoma and its immunohistochemical features. The associated features of Cryptogenic organising pneumonia and post obstructive bronchiectasis are additional features which make the case more interesting. Awareness of this rare entity can prevent clinical misdiagnosis. Keywords: Pleomorphic adenoma, Pulmonary, Bronchus. Introduction Pleomorphic adenoma (PA), a common salivary gland tumor of the head and neck is a rare occurrence in the lung.[1] With the 35 cases reported,[2] we report a rare case of Primary pulmonary pleomorphic adenoma (PPPA) associated with Cryptogenic organising pneumonia. PA is a tumor with both epithelial and connective tissue differentiation consisting of glands intermingled with myoepithelial cells in a myxoid and chondroid stroma.[3]They are slow growing but with a potential to recur or metastasize.[2] Case Report A 37 year old man was referred to our hospital with a 2 month history of breathlessness, cough and right sided pleural effusion. He was found to have an obstructive lesion in the right intermediate bronchus on chest x-ray and bronchoscopy (Fig. 1a). There was no submandibular or parotid gland enlargement. The laboratory studies, including the peripheral blood smear, biochemical examination, and abdominal ultrasound showed no abnormalities. A right lower bilobectomy (middle and lower) was done with a clinical diagnosis of Carcinoid – right bronchus. Macroscopic examination showed a 2.8cm sized well circumscribed bluish white glistening homogenous unencapsulated mass in the right middle lobe bronchus (Fig. 1b). Microscopy showed a well circumscribed biphasic tumor made up of epithelial and mesenchymal components. Epithelial component was seen in the form of ductal lumina lined by cuboidal epithelium, surrounded by myoepithelial cells in shee