Sa1563 Differential Diagnosis of Solid Pancreatic Masses: Do Procore Histology Needles Improve the Diagnostic Yield of Standard Cytology Needles?

Abstract

Differential Diagnosis of Solid Pancreatic Masses: Do Procore Histology Needles Improve the Diagnostic Yield of Standard Cytology Needles? Julio Iglesias-Garcia*, Ihab Abdulkader, Jose Larino-Noia, Enrique Dominguez-Munoz Gastroenterology, University Hospital of Santiago, Santiago de Compostela, Spain; Foundation for research in digestive diseases, Santiago de Compostela, Spain; Pathology, University Hospital of Santiago, Santiago de Compostela, Spain Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) is an accurate technique for sampling pancreatic solid lesions. However, cytology has a limited yield and accuracy, which may be overcome if histological specimens are provided to the pathologist. Aim of the study was to evaluate the accuracy of the newly developed 19-gauge and 22-gauge Procore needles, compared to the standard FNA needles. Methods: 203 consecutive patients (mean age 66.4 years, range 28-92, 123 male), who underwent EUS for the evaluation of solid pancreatic masses were prospectively included in the study. EUS was performed using a convex array echoendoscope, connected to an ultrasound equipment. Samples obtained with Procore needles (19 and 22 gauge, Cook Medical Inc, Limerick Ireland), were recovered into cytolit and processed for histological analysis, after just one needle pass. Samples obtained with standard cytology needles (22 and 25 gauge, Cook Medical Inc, Limerick Ireland), were recovered into slides and fixed for cytological evaluation, following the standard methodology after 2-4 needle passes. Results were compared to the gold standard of surgical histopathology, or global clinical and radiological assessment and follow-up in non-operated cases. Results are shown as mean or percentage (95%CI), and compared by chi-square test. Diagnostic accuracy was evaluated. Results: Mean size of solid pancreatic masses was 38.3 18.9 mm. 127 tumors were located in the head of the pancreas, 62 in the body, and 14 in the tail. 80 punctures (39.4%) were performed with Procore needles (35 with 19-gauge and 45 with 22-gauge), and 123 (60.6%) with standard cytology needles (72 with 25gauge and 59 with 22-gauge). Sensitivity, specificity, PPV and NPV for malignancy were 92.5%, 100%, 100% and 70.5% respectively with Procore needles, and 74.5%, 100%, 100% and 45% respectively with standard citology needles. Overall diagnostic accuracy of Procore needles (93.75%) was significantly higher than cytology needles (79.7%) (p 0.0039). Conclusion: EUSguided biopsy of solid pancreatic masses with the new Procore needle is significantly more accurate than with the standard cytology needle.