Impact of endoscopic ultrasound-guided fine needle aspiration of small lymph nodes

Abstract

Abstract Background: There is very limited literature on results of fine needle aspiration (FNA) of small (defined as ≤1 cm at long and short axis) lymph nodes, particularly in the setting of pyrexia of unknown origin (PUO). Methods: The study was conducted from July 2014 to December 2015 at a tertiary care center. A total of 34 endoscopic ultrasound (EUS)-guided FNAs in 33 patients were done for lymph nodes ≤1 cm at long and short axis and these were included in the analysis. Results: The study cohort comprised 33 patients; 23 males and 10 females, mean age of 58 ± 12 years. Indication of FNA was to look for malignancy (n = 15), PUO (n = 16), unexplained weight loss (n = 1), and presence of lymphadenopathy in prospective liver donor (n = 1). The FNA was taken from mediastinal nodes (n = 20, 14 subcarinal) and abdominal (n = 14, 8 at porta). The mean size of lymph nodes was 87 ± 11 mm at large axis and 68 ± 17 mm at short axis. A total of 3 (8.8%) FNAs were nondiagnostic (inadequate material). The cytopathologic diagnosis was malignancy in 8 (23.5%), granulomatous change in 8 (23.5%), and reactive lymphadenopathy in 15 (44.1%). Thus, EUS-guided FNA of these small nodes changed the management decisions in 44% of cases (one patient had tubercular lymphadenopathy at two sites). The 22-gauge EUS FNA needle was used in majority of patients (n = 26). There was no significant difference between pathologic (malignant and granulomatous) and reactive lymph nodes regarding size at long or short axis, ratio of long and short axis, hypoechogenicity, and sharply defined borders. Conclusion: EUS-guided FNA of small lymph nodes showed pathological enlargement in 44% of cases.