Predictors of malignancy in EUS-guided FNA for mediastinal lymphadenopathy in patients without history of lung cancer

Background: Mediastinal lymphadenopathy (ML) poses a great diagnostic challenge. Objective: To investigate the predictors of malignancy in endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) of ML in patients without known lung cancer. Design: Retrospective study. Setting: Tertiary referral center. Methods: One hundred eight patients without known lung cancer who underwent EUS guided-FNA for ML between 2000 and 2007. All subjects underwent EUS-guided FNA. Data was collected on patients′ demographics, and lymph node (LN) characteristics. Diagnosis of LN malignancy was based on FNA findings and clinical follow-up. Results: One hundred eight patients were analyzed; 58 (54%) were men and 87 (79%) were Caucasian. Mean age was 55 years. Prior malignancy was present in 48 (43%) patients. A total of 126 FNA samples from 126 distinct LNs were performed. Twenty-five (20%) LNs were positive for malignancy. Mean short and long-axis for LNs were 13 and 29 mms respectively. Round shape and sharp borders were found in 29 (15%) and 25 (22%) LNs, correspondingly. Independent predictors of a malignant FNA were: Prior cancer (OR 13.10; 95% CI 2.7-63.32; P = 0.001), short axis (OR 1.10; 95% CI 1.00-1.22; P = 0.041) and sharp LN borders (OR 5.47; 95% CI 1.01-29.51; P = 0.048). Age, race, gender, long axis, round shape were not associated with cancer in our cohort. Limitations: Retrospective design and lack of surgical gold standard. Conclusions: Increased risk of malignancy was associated with prior history of cancer, larger LN short axis and presence of LN sharp borders. These predictors may help guide endoscopists perform FNA in malignant LNs, increasing the overall efficiency of EUS-FNA for ML.