Prevalence of Benign Diseases Mimicking Lung Cancer: Experience from a University Hospital of Southern Brazil

BACKGROUND: Lung cancer is the most lethal type of cancer in the world. Several benign lung diseases may mimic lung carcinoma in its clinical and radiological presentation, which makes the differential diagnosis for granulomatous diseases more relevant in endemic regions like Brazil. This study was designed to describe the prevalence and the diagnostic work-up of benign diseases that mimic primary lung cancer in patients hospitalized at a university hospital from south of Brazil. METHODS: This was a transversal study, which evaluated the medical records of 1,056 patients hospitalized for lung cancer treatment from September 2003 to September 2013 at University Hospital of Santa Maria. RESULTS: Eight hundred and four patients underwent invasive procedures for suspected primary lung carcinoma. Primary lung cancer was confirmed in 77.4% of the patients. Benign disease was confirmed in 8% of all patients. Tuberculosis (n=14) and paracoccidioidomycosis (n=9) were the most frequent infectious diseases. The diagnosis of benign diseases was obtained by flexible bronchoscopy in 55.6% of the cases and by thoracotomy in 33.4%. CONCLUSION: Infectious diseases are the most frequent benign diseases mimicking lung cancer at their initial presentation. Many of these cases could be diagnosed by minimally invasive procedures such as flexible bronchoscopy. Benign diseases should be included in the differential diagnosis during the investigation for primary lung cancer in order to avoid higher cost procedures and mortality.