CT-guided biopsy of pulmonary nodules ≤10 mm: Diagnostic yield based on nodules' lobar and segmental distribution

Purpose: The aim of our study is to evaluate the diagnostic performance of CT-guided biopsy of lung nodules ≤10 mm based on their lobar and segmental location.

Materials and methods: This was a retrospective study performed on 193 CT-guided percutaneous transthoracic needle biopsies of lung nodules ≤10 mm in greatest dimension, between January 1, 2013 and April 30, 2019. Biopsies were classified as either diagnostic or non-diagnostic based on final cytology and surgical pathology reports. Diagnostic results were those that met parameters for malignancy or a specific benign diagnosis, whereas atypical cells, non-specific benignity, or insufficient specimen were considered non-diagnostic.

Results: A total of 1577 CT-guided percutaneous transthoracic needle biopsies were reviewed. Of these, 193 nodules (12.24%) measured ≤10 mm and were selected for further analysis. Of the 193 biopsies, 138 yielded diagnostic results while 56 yielded nondiagnostic results (71% vs 29%, respectively). When analyzed by nodule location, the superior segments of the lower lobes boasted the highest diagnostic yield compared to nodules located in the basal segments of the lower lobes which had the lowest diagnostic yield (84.2% vs 64.7%, respectively). Nodules in the upper lobes and in the middle lobes had a diagnostic yield of 70% and 66.7%, respectively.

Conclusion: The diagnostic performance of CT-guided biopsy of lung nodules ≤10 mm in diameter may be affected by lobar and segmental location. While the overall performance was good (diagnostic yield of 71%), the yield varied nearly 20% depending on location.