Conventional transbronchial needle aspiration (C-TBNA) is a minimally invasive, safe, and cost-effective technique in evaluating mediastinal lymphadenopathy. Previously we reported that the skills for C-TBNA can be acquired from the books. We studied the learning curve for C-TBNA for a single bronchoscopist at a tertiary-care center where ultrasound technology remains difficult to acquire .
We prospectively collected results of the first 99 consecutively performed C-TBNA between December 2009 and 2013. Patients were divided into 3 groups: (I): First 33, (II): Next 33 and (III): Last 33. Results were categorized as malignant, non-malignant or non-diagnostic. Diagnostic yield (DY), sensitivity (SEN), specificity (SPE), positive and negative predictive values (PPV, NPV), and accuracy (ACC) were calculated to learn the learning curve for C-TBNA.
Total 99 patients (M:F = 62:37), mean age 58.2 ± 11.5 years, mean LN diameter 26.9 ± 9.8 mm underwent C-TBNA. Sixty-nine patients had lymph nodes (LNs) >20 mm in diameter. Final diagnoses were established by C-TBNA in 44 (yield 44.4%), mediastinoscopy 47, transthoracic needle aspiration 5, endobronchial biopsy 2 and peripheral LN biopsy 1. C-TBNA was exclusively diagnostic in 35.4%. Group I: DY: 42.4%, 64.7% in malignancies, 19% in benign conditions (P = 0.008). SEN, SPE, PPV, NPV, ACC = 70%, 100%, 100%, 66.6%, 78.7%, respectively. Group II: DY: 54.5% (36.4% exclusive), 88.2% in malignancies and 19% benign conditions (P = 0.000). SEN, SPE, PPV, NPV, ACC=72%, 100%, 100%, 53.3%, 78.7%, respectively. Group III: DY: 36.3% (27% exclusive), 100% in malignancies and 16% in benign conditions. SEN, SPE, PPV, NPV, ACC = 92.3%, 100%, 100%, 95.2%, 97%, respectively. No difference was found in relation to LN size or location and TBNA yield.
C-TBNA can be easily learned and the proficiency can be attained with <66 procedures. In selected patients, its exclusivity could exceed 35%.