Frequency and characterization of celiac ganglia diagnosed on fine-needle aspiration

INTRODUCTION: Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) is frequently used to sample intra-abdominal lesions and lymph nodes. Celiac ganglia normally located near the celiac artery may be sampled during these procedures. The aim of this study was to determine the frequency of detection and cytologic findings of celiac ganglia diagnosed on FNA. MATERIALS AND METHODS: A 14-year retrospective review of radiologic and endoscopic FNA cases involving the celiac region was performed. Cases in which ganglia were reported were further analyzed and slides reviewed. RESULTS: A total of 354 patients underwent FNA of a suspected celiac lymph node (334 patients) or celiac mass (20 cases). In 9 of these patients (2.5%), ganglion cells were identified. These were identified in cases only after 2008 via EUS-guided FNA. Aspirates were hypocellular and bloody. Large ganglion cells were either sparsely dispersed or present in clusters. Ganglion cells had a low N: C ratio, granular cytoplasm with neuromelanin, and eccentric small round nucleus with a prominent nucleolus. One specimen had concomitant pancreatic adenocarcinoma. None of these cases had a false positive on-site adequacy assessment or final misdiagnosis. CONCLUSIONS: These data show that celiac ganglia may be infrequently encountered, especially with intra-abdominal EUS-guided FNA targeting nodes or masses near the celiac region. Therefore, cytologists should be aware of the possibility of finding ganglionic cells in EUS-guided FNA samples.