Surgical treatment of organising pneumonia mimicking lung cancer: experience of 27 patients.

Objectives: Organising pneumonia as a localised process has sometimes been managed by surgery. This poorly defined entity has been mistaken clinically, roentgenographically and usually at exploratory thoracotomy for lung cancer. This series details our experiences with surgical resections in 27 patients during the past 13 years.

Methods: Surgical lung resection was performed through wedge resection or lobectomy with or without video-assisted thoracoscopic surgery. Resected specimens were swabbed for aerobic and anaerobic bacterial, fungal and mycobacterial cultures. Clinical presentation, roentgenological examination, location and size of the tumourous lesions, pathological finding and treatment were investigated.

Results: The patients were between 41 and 80 years of age. Most of the patients (81.5%) presented with cough, haemoptysis and weight loss. The common radiographic findings were round or oval mass with occasionally air bronchogram. Thirteen patients underwent non-invasive biopsy without conclusive diagnosis. The tumour size ranged from 1.5 cm to 8.5 cm. The typically grossly involved area was sharply outlined, firm and extended to the pleura, which was invariably thickened. The microscopic pattern was also rather similar, with inflammation in various degrees of organisation, sometimes accompanied by necrotising changes in the bronchi. Viridans Streptococci and Neisseria spp. were identified as the aetiologic agents in 15 cases (55.6%). All patients had an excellent outcome.

Conclusion: The usual investigative procedures for pulmonary mass were of little aid in establishing the differential diagnosis of organising pneumonia from neoplasm. Surgical resection should be considered in the absence of a positive diagnosis of a persistent pulmonary mass.