Clinical implications of granulomatous inflammation detected by endobronchial ultrasound transbronchial needle aspiration in patients with suspected cancer recurrence in the mediastinum

All 153 consecutive patients undergoing EBUS-TBNA in an academic cancer institution for suspected cancer in the mediastinum (mediastinal lymphadenopathy by CT imaging) were reviewed. Patients with non-caseating granuloma identified by EBUS-TBNA were included.EBUS-TBNA identified non-caseating granuloma in 17/153 (11%) patients. A subset of 8/153 (5.2%) had sarcoid like lymphadenopathy mimicking cancer recurrence (5/5 PET positive). Another 8/153 (5.2%) patients with new mediastinal lymphadenopathy and no prior history of cancer had a clinical syndrome consistent with sarcoidosis. One other patient with a history of breast cancer was diagnosed with non-tuberculous mycobacteria infection. No patient required mediastinoscopy and there were no complications.In an academic cancer institute, at least 5% of patients undergoing EBUS-TBNA have sarcoid-like lymphadenopathy mimicking cancer recurrence. Further studies to define the precise etiology, natural history and prognosis of this phenomenon are warranted.In patients with a history of cancer, the onset of mediastinal adenopathy often heralds a recurrence of their malignancy. However, not all mediastinal adenopathy is due to cancer recurrence and lymph node sampling is warranted. Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) allows real time assessment and biopsy of mediastinal lymph nodes and therefore often obviates the need for mediastinoscopy [1,2]. The utility of EBUS-TBNA in the mediastinal nodal staging of lung cancer has been defined [3]. More recently, the ability of EBUS-TBNA to identify granuloma in the work-up of patients with mediastinal adenopathy secondary to suspected sarcoidosis has been reported [4]. Since the beginning of the last century, "local sarcoid reactions" and "sarcoid like lymphadenopathy" with pulmonary and mediastinal involvement have been described in patients with cancer [5-7]. In this report, we describe a group of patients in whom EBUS-TBNA detected granulomatous