[Transbronchial needle aspiration in the study of mediastinal lymph nodes: yield and cost-effectiveness]. / Punción transbronquial aspirativa en el estudio de las adenopatías mediastínicas: rentabilidad y coste-beneficio.

OBJECTIVE: The role of different techniques for mediastinal staging in patients with suspected lung cancer is a subject of debate. The aim of this study was to analyze the diagnostic yield and cost-effectiveness of transbronchial needle aspiration in the mediastinal staging of lung cancer in patients being evaluated in a tertiary hospital. PATIENTS AND METHODS: This was a retrospective, observational study of the results of transbronchial needle aspiration in patients with suspected lung cancer and mediastinal lymph node involvement. A cost-effectiveness analysis of the systematic use of this technique was also performed. RESULTS: One-hundred ninety-four patients (85% men, 15% women) were evaluated. The diagnosis of lung cancer was confirmed in 157 (81%). Cytology samples obtained by transbronchial needle aspiration were adequate in 147 (76%) of the 194 cases. When only the adequate samples were included in the analysis, transbronchial needle aspiration showed a sensitivity of 88%, specificity of 100%, positive predictive value of 100%, negative predictive value of 64%, and efficiency of 90%. Mediastinoscopy was avoided in 44 (34%) of the 127 patients with localized non-small cell lung cancer, with an estimated saving of euro 119,456. CONCLUSIONS: Transbronchial needle aspiration has a high diagnostic yield and obviates the need for mediastinoscopy in a significant percentage of cases. This finding is of diagnostic and economic significance.