Pulmonary Tuberculosis Mimicking a Lung Cancer: a Case Series

Tuberculosis (TB) is an infectious disease that is caused by Mycobacterium tuberculosis. Despite TB being a preventable and curable disease, it still remains to be one of the leading causes of mortality worldwide and continues to be prevalent. TB can manifest in multiple  systems, but its primary target is the lungs. Pulmonary TB can present differently depending on the patient's immune status and  comorbidities. One atypical presentation of TB is lung mass, which can mimic lung malignancy and cause diagnostic delays.In this case  series, we report on four cases in which TB was initially suspected to be lung malignancy. All four patients had lung masses on diagnostic  imaging; microbiological testing was positive in only two of the patients and bronchoscopic abnormalities were seen in two of those. In  two of the four cases, caseating granulomas were present on biopsy. All four patients attained clinical and radiologic resolution.In  conclusion, despite years of knowledge and the prevalence of TB, atypical presentations can still cause diagnostic delays and unnecessary  interventions. This case series provides examples of TB mimicking lung cancer, so considering TB as a differential diagnosis  for patients presenting with a lung mass is crucial.