CT-guided percutaneous lung biopsy: Correlation between diagnostic yield, lung lesion size, and lobar distribution

Objectives: The aim of this retrospective study was to investigate the relationship between lung lesion lobar distribution, lesion size, and lung biopsy diagnostic yield. Material and Methods: This retrospective study was performed between January 1, 2013, and April 30, 2019, on CT-guided percutaneous transthoracic needle biopsies of 1522 lung lesions, median size 3.65 cm (range: 0.5– 15.5 cm). Lung lesions were localized as follows: upper lobes, right middle lobe and lingual, lower lobes superior segments, and lower lobes basal segments. Biopsies were classified as either diagnostic or non-diagnostic based on final cytology and/or pathology reports. Results were considered diagnostic if malignancy or a specific benign diagnosis was established, whereas atypical cells, non-specific benignity, or insufficient specimen were considered non-diagnostic. Results: The positive predictive value (PPV) of a diagnostic yield was 85%, regardless of lobar distribution. Because all PPVs were relatively high across locations (84–87%), we failed to find statistically significant difference in PPV between locations (P = 0.79). Furthermore, for every 1 cm increase in target size, the odds of a diagnostic yield increased by 1.42-fold or 42% above 85%. Although target size increased the diagnostic yield differently by location (between 1.4- and 1.8-fold across locations), these differences failed to be statistically significant, P = 0.55. Conclusion: Percutaneous transthoracic needle biopsy of lung lesions achieved high diagnostic yield (PPV: 84– 87%) across all lobes. A 42% odds increase in yield was achieved for every 1 cm increase in target size. However, this increase in size failed to be statistically significant between lobes.