Role of endoscopic ultrasound-guided fine-needle aspiration in the diagnosis and classification of lymphomas.

Background Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and effective technique in the diagnosis of mediastinal and abdominal masses. However, the usefulness of EUS-FNA in the diagnosis and classification of lymphomas is controversial. Our aim was to determine the yield of EUS-FNA in the diagnosis and classification of lymphomas. Methods A retrospective case series was performed in a tertiary referral center. All consecutive patients referred for EUS-FNA who had a suspected diagnosis of lymphoma from March 2013 to June 2019 were included. Results 35 patients (54.3% women, median age 72 years) were included. The most frequent localization of the node was the abdomen (67.9%). Nodes were punctured using 22-gauge (85.7%) and 19-gauge needle (14.3%) with slow-pull technique. The number of passes performed were three or more in 82.9% of patients. The samples were processed by cell block method. Adequate samples for immunohistochemical and molecular biological study were obtained in 33 (94.3%) patients. EUS-FNA correctly diagnosed lymphoma in 30 out of 35 patients (85.7%), and subclassification was determined in 23 patients (65.7%). The most frequent diagnosis was Non-Hodgkin Lymphoma (85.7%). There was one moderate adverse event (bleeding), which was solved during the procedure. Conclusions EUS-FNA may be a valuable technique in the evaluation of suspected lymphomas with an adequate diagnostic yield and a very low adverse events rate.