Significance of Granulomas Detected in Mediastinal Lymph Nodes by Fine Needle Aspiration (EUS-FNA and EBUS-TBNA) in Patients with Malignancies.
Melissa K Hart, Karla K Dunning, David Tasso, Evin H Gulbahce, Stephen C Schmechel, Deniz L Aslan, Stefan E Pambuccian. University of Minnesota, Minneapolis
Background: EUS-FNA and EBUS-TBNA are minimally invasive biopsy techniques useful in the diagnosis of mediastinal lymph node metastases from intrathoracic and extrathoracic malignancies and the diagnosis of mediastinal sarcoidosis. The aim of this study was to review our experience with the cytologic diagnosis of granulomas in patients with pulmonary and extrathoracic malignancies.
Design: We performed a retrospective review of all cytologic diagnoses of granulomas in mediastinal lymph nodes obtained from 9/1/2004 to 3/30/2010 in patients with a concurrent or preceding diagnosis of malignancy. Demographic information, previous malignancy data, symptoms, imaging findings, and follow-up information was extracted through electronic chart review.
Results: 65 patients had cytologically diagnosed mediastinal granulomas; of these 20 (8M, 12F, aged 36-83, mean 60y) had a previously or concurrently diagnosed malignancy: 3 non-small cell carcinoma of the lung (1 adenocarcinoma (ADCA), 1 squamous cell carcinoma (SqCC), 1 NSCC NOS), 3 non-Hodgkin lymphomas, 2 breast carcinomas, 2 gastric ADCA, 2 head and neck SqCC, 1 cervical and 1 anorectal SqCC, 1 hepatocellular carcinoma, 1 thyroid papillary carcinoma, 1 melanoma and 1 malignant fibrous histiocytomas of soft tissues. Malignancy was diagnosed <1 year prior to the diagnosis of mediastinal granulomas in most cases.
The abnormal mediastinal lymph nodes that were sampled by EUS (8 cases) or EBUS (12 cases) were located in descending order in stations 7, 4R, 4L and 11R and 11L and measured 0.8-3 cm (mean 1.6) on CT and had an SUV of 5.4-9.7 (mean 7) on PET. Most patients were asymptomatic and none had a prior history of sarcoidosis. Metastatic disease was clinically suspected in most cases. The granulomas were nonnecrotizing in 15 (all with negative AFB and GMS stains) and necrotizing in 5 cases, two of which showed Histoplasma on GMS stains. Flow cytometry immunophenotyping was performed and was negative in all cases with a history of lymphoma. Follow-up histologic sampling by mediastinoscopy (9 cases) or repeat FNA (2 cases) confirmed the original diagnosis; no malignancies were found. None of the patients had an increase in size of mediastinal lymph nodes or developed mediastinal metastases during a mean two year follow-up period.
Conclusions: EBUS FNA accurately diagnosed the granulomatous disease in all patients with follow-up histologic diagnoses. The significance of sarcoid-like granulomas in patients with malignancies is incompletely understood and deserves further study.
Monday, February 28, 2011 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 53, Monday Morning