Validity of endoscopic ultrasonography-guided fine needle aspiration of mediastinal and abdominal lymph nodes in daily clinical practice Background: According to recent clinical trials, EUS-FNA has a high diagnostic yield in case of mediastinal and abdominal lymphadenopathy. However, it is questionable, if the results of centers of excellence can be maintained in daily clinical practice. Methods: We retrospectively analyzed the results of 141 EUS-FNP in 121 patients (female 25, male 86; mean age 61,5 years, range 22-87) of 119 mediastinal and 22 abdominal lymph nodes, performed under routine conditions in daily clinical practice in a community hospital. Histopathological examination of operative specimens or clinical follow-up served as gold standard. Results: In 124/141 (80%) of cases, adequate specimens could be obtained, irrespective of lymph node size. During follow-up, the rate of adequate specimens obtained increased from 77% (2002-2006) to 98% (2007-2010). Sensitivity and specifity for the diagnosis of malignancy was 77 and 100% (diagnostic accuracy 92%). During follow-up, a relevant learning curve could be observed with a significant increase in sensitivity (72 to 80%). Conclusion: In comparison to the results of centers of excellence, our diagnostic accuracy is slightly inferior. However, even in daily routine praxis, EUS-FNP is a safe and accurate method of sampling mediastinal and abdominal lymph nodes.