Mediastinal lymph node enlargement is common in the follow-up of patients with previously treated malignancies. The aim of this study is to assess the role of endobronchial ultrasound (EBUS) transbronchial needle aspiration (TBNA) for cyto-histological evaluation of positron emission tomography with 18fluorodeoxyglucose (PET) positive mediastinal and hilar lymph nodes developed in patients with previous malignancies. All EBUS-TBNA cases performed from January 2012 to May 2016 were retrospective reviewed. Results of EBUS-TBNA in patients with mediastinal and/or hilar lymphadenopathies were analysed. Non-malignant cytopathologies were confirmed with surgical procedures or clinical and radiological follow-up. Among 1780 patients, 176 were included in the analysis. 103 of these (58.5%) had a diagnosis of tumour recurrence whereas 73 (41.5%) had a different diagnosis: 63 (35.8%) had a non-neoplastic diagnosis and 8 patients (4.6%) had a different cell type malignancy. Samples were false-negative in 5 (2.8%) out of 176 patients. The overall sensitivity, specificity, negative predicted value and diagnostic accuracy were 95.7% (95% CI 90.2-98.6%), 100% (95% CI 94.0-100%), 92.3% (95% CI 83.2-96.7%) and 97.2% (95% CI 93.5-98.8%), respectively. EBUS-TBNA demonstrated a pathological diagnosis different from the previous tumour in a large percentage of patients, confirming its strategic role in the management of patients with previously treated malignancies.