Nontuberculous mycobacterial pulmonary disease mimicking lung cancer

Abstract

To describe the features and clinical implications of computed tomography (CT), positron emission tomography (PET), and percutaneous needle aspiration biopsy (PCNB) in pulmonary nontuberculous mycobacterial (NTM) disease manifesting as a solitary nodule, mass, or mass-like consolidation mimicking malignancy.Among a cohort of 388 patients with NTM pulmonary disease, 14 patients with clinically and radiologically suspected lung cancer were included in our study. Two chest radiologists evaluated CT features, including lesion type (nodule, mass, or mass-like consolidation), morphologic features (margin, degree of enhancement, calcification), and presence of accompanying findings suggestive of NTM pulmonary disease (bronchiectasis with clustered centrilobular nodules or upper-lobe cavitary lesions) by consensus. Diagnostic procedures for microbiologic diagnosis of NTM disease and clinical outcome were reviewed.Incidence of NTM pulmonary disease presenting as solitary nodule/mass (n = 8) or mass-like consolidation (n = 6) was 3.6% (14 of 388). Most lesions were detected incidentally during routine health check-up or evaluation of other disease (11 of 14, 79%). Lesions typically showed poor contrast-enhancement (9 of 12) and internal calcification (6 of 14). No lesions had CT features suggestive of NTM pulmonary disease. All 4 lesions for which PET/CT imaging was performed showed strong fluorodeoxyglucose uptake simulating malignant lesions (mean, 4.9; range, 3.6–7.8). PCNB revealed mycobacterial histology in 6 of 11 specimens and positive culture results were obtained for 7 of 7 specimens.NTM pulmonary disease may present as a solitary nodule, mass, or mass-like consolidation mimicking malignancy. CT features and PCNB are important to diagnose NTM disease mimicking lung cancer to avoid unnecessary surgery.

The Presence of Coexisting Lung Cancer and Non-Tuberculous Mycobacterium in a Solitary Mass

“…Pulmonary NTM infections often occur in the context of preexisting lung disease, especially chronic obstructive pulmonary disease (COPD), bronchiectasis, and previous tuberculosis [ 4 , 5 ]. NTM pulmonary diseases are classified into fibrocavitary disease and nodular bronchiectatic disease depending on radiologic patterns [ 6 ].…”

“…NTM pulmonary diseases are classified into fibrocavitary disease and nodular bronchiectatic disease depending on radiologic patterns [ 6 ]. The characteristic radiologic features of fibrocavitary disease include heterogeneous nodular and cavitary opacities, whereas those of nodular bronchiectatic disease are bronchiectasis and branching centrilobular nodules [ 5 , 6 ].…”

“…Non-tuberculous mycobacterium (NTM) pulmonary disease has been found in 2.0–8.5% of patients with lung cancer [ 1 – 4 ]. However, the coexistence of lung cancer and NTM pulmonary disease in a solitary nodule or mass is very rare [ 2 , 4 , 5 ]. On the other hand, the computed tomography (CT) findings of NTM pulmonary disease can mimic lung cancer as a solitary pulmonary nodule or mass [ 5 ].…”

“…However, the coexistence of lung cancer and NTM pulmonary disease in a solitary nodule or mass is very rare [ 2 , 4 , 5 ]. On the other hand, the computed tomography (CT) findings of NTM pulmonary disease can mimic lung cancer as a solitary pulmonary nodule or mass [ 5 ]. Therefore, during a bronchoscope examination, which comprises a transbronchial lung biopsy (TBLB) as well as a bronchial brushing and lavage, is very important to distinguish one from the other; a positive culture result for sputum or bronchial lavage fluid does not exclude the possibility of concomitant lung cancer [ 5 ].…”

A rare case of cavitary lung cancer complicated with mycotic pneumonia and bullous emphysema

“…[ 22 ] Pulmonary mycobacterial disease mimics lung cancer, therefore biopsy is essential to avoid unnecessary surgery. [ 23 ]…”