Comparison of transbronchial needle aspiration with and without ultrasound guidance for diagnosing benign lymph node adenopathy

Abstract

Background: Transbronchial needle aspiration (TBNA) is a minimally invasive procedure performed to diagnose lymph node (LN) adenopathy. TBNA with and without endobronchial ultrasound (EBUS) guidance has a high diagnostic yield for malignant LN enlargement, but the value for diagnosing benign LN enlargement has been less thoroughly investigated.

Methods: We retrospectively evaluated 3540 patients with mediastinal LN enlargement who received TBNA. One hundred sixty-six patients with benign mediastinal lymphadenopathy were included and 293 LNs were biopsied. A positive result was defined as a specific histological abnormality. Conventional TBNA (cTBNA) and EBUS-TBNA, as well as cTBNA and transbronchial forceps biopsy (TBFB), were compared. The subgroup analysis was stratified by disease type and LN size.

Results: A diagnosis was made in 76.84% of the EBUS-TBNA and 61.31% of the cTBNA (P < 0.05). EBUS-TBNA was superior to cTBNA for both granulomatous (65.18% vs. 45.45%, P < 0.05) and non-granulomatous disease (96.92% vs. 84.06%, P < 0.05). In contrast, the diagnostic yield of EBUS-TBNA was higher than that of cTBNA for LNs < 20 mm (79.44% vs. 64.29%, P < 0.05), but for LNs > 20 mm the difference was marginal. These findings were confirmed in a group of independent patients who received cTBNA plus EBUS-TBNA. The diagnostic yield did not differ between cTBNA and TBFB, but significantly increased to 76.67% when both modalities were employed.

Conclusions: EBUS-TBNA is the preferred minimally invasive diagnostic method for benign mediastinal LN disease. Combined cTBNA and TBFB is a safe and feasible alternative when EBUS is unavailable.

Keywords: Benign mediastinal lymphadenopathy; Endobronchial ultrasound TBNA (EBUS-TBNA); Transbronchial forceps biopsy (TBFB); Transbronchial needle aspiration (TBNA).

Fig. 1

Flow diagram of patient inclusion

Fig. 2

Morphological manifestations of two representative cases with lymph node mucormycosis and tuberculosis, respectively. Broad, non-septate and thick-walled hyphae are seen with right angle branching (arrow), indicating mucormycosis (a. H&E staining × 200). Cyst-like sections (arrows) of the Mucor hyphae are more prominent on staining of periodic acid-silver methenamine (PASM) (b. PASM staining × 200). Aggregation with epithelioid cells (inside arrows,) is present (c. H&E staining × 400), accompanied with typical Langerhans giant cells (*) and caseous necrosis (^), indicating tuberculosis (d. H&E staining × 400). Positive bacilli (arrows) of acid-fast staining are found (e, f. acid-fast staining × 400)