Mo1412 The 25G FNA Needle: Good for Onsite but Poor for Offsite Evaluation? Results of a Randomized Trial

years) with an EUS finding of pancreatic solid lesion were included in the study. Cytological final diagnosis was adenocarcinoma in 25/30 (83.3%) cases, neuroendocrine tumor 1/30 (3.3%), IPMN with high grade dysplasia 2/30 (6.7%), GIST in 1/30 (3.3%) and negative for malignant cells 1/30 (3.3%). The difference between the overall blood amount score per technique was not statistically significant (pZ0.61) as well as the cellularity score (pZ0.08). In 13/30 pts (43%) the two techniques reported concordant T/N ratio. In 6/30 pts (20%) final diagnosis was achieved only by capillary obtained smears. In 1/30 pt (3.3%) the diagnosis was done with aspiration. In the remnant, the ratio between the two techniques was similar. Adequacy was reached in 24/30 (80%) with aspiration and 29/30 (97%) with capillary technique (pZ 0.04). Conclusions: Aspiration and capillary sampling techniques provided similar results in cellularity and blood amount. However adequacy rate was significantly superior in capillary technique. Furthermore, in 20% of cases, final diagnosis was achieved only with capillary samples. Mo1412 The 25G FNA Needle: Good for Onsite but Poor for Offsite Evaluation? Results of a Randomized Trial Shyam Varadarajulu*, Bronte a. Holt, Muhammad Hasan, Ji Young Bang, Amy L. Logue, Robert Hawes, Shantel Hebert-Magee Center for Interventional Endoscopy, Florida Hospital, Orlando, FL Background: The diagnostic performance of EUS-FNA is related to the availability of a high quality onsite cytopathologist. When onsite cytopathology support is not available, FNA is performed for cell block preparation to allow offsite interpretation. Although a recent meta-analysis has proven the superiority of the 25G needle for sampling solid pancreatic masses, there is no data on the optimal number of passes required to obtain a diagnostic cell block. Aim: To identify the number of passes required to obtain a diagnostic cell block when using a 25G needle for sampling pancreatic mass lesions. Methods: Consecutive patients with solid pancreatic masses underwent EUS-FNA using a 25G needle. Once preliminary onsite diagnosis was established, patients were randomized to undergo either two or four FNA passes (fanning technique) using the same needle for cell block preparation. The same pathologist who rendered onsite diagnosis evaluated the cell block specimens at a later time but was blinded to information on patients, onsite diagnosis and randomization sequence. Cell block was evaluated for (a) presence of tissue pellet, (b) size of pellet and (c) diagnostic accuracy (tissue representative of final diagnosis). Final diagnosis was established by long-term patient follow-up or surgical histology. Based on prior literature, sample size was estimated at 62 patients. Results: 62 patients (Female 54.8%, median ageZ 71yrs) were randomized to undergo either two (nZ31) or four (nZ31) FNA passes for cell block. Prior to randomization, onsite diagnosis was established in all 62 patients with a diagnostic accuracy of 100%. The median number of passes required to establish onsite diagnosis was 1 (IQRZ1-2). The final diagnosis was adenocarcinoma in 45 (72.5%), neuroendocrine/other tumor in 7 (11.3%) and chronic pancreatitis in 10 (16.1%). There was no difference in patient or tumor characteristics between the randomized cohorts (Table). There was no difference in the presence of tissue pellet (93.5 vs. 96.8%; pZ0.99), median size of tissue pellet (0.006 vs.0.05mm; pZ0.11) or diagnostic accuracy (80.6% vs. 80.6%; pZ0.99) between patients randomized to two or four FNA passes, respectively. SUMMARY: Despite establishing a 100% onsite diagnosis, the same 25G needle when used in the same mass yielded a diagnostic cell block in only 80% of patients, irrespective of the number of FNA passes performed. Conclusions: While the aspirate obtained from a 25G needle is excellent for onsite evaluation, the cell block obtained from it is suboptimal for off-site interpretation. The role of larger gauge needles to obtain a better cell block needs investigation. These findings have important implications for centers and endosonographers that do not have access to onsite cytopathology services. www.giejournal.org Two FNA Passes (N[31) Four FNA Passes (N[31) p Median passes to onsite diagnosis, n (IQR) 1 (1-2) 1 (1-2) 0.68 Median tumor size, mm (IQR) 30 (19-40) 35 (22-40) 0.26 Vascular invasion, n (%) 18 (58.1) 20 (64.5) 0.60 Tumor in head/uncinate, n (%) Body/tail, n(%) 27 (87.1) 4 (12.9) 24 (77.4) 7 (22.6) 0.51 Diagnostic accuracy of cell block, n (%) 25 (80.6) 25 (80.6) 0.99 Mo1413 EUS-Guided Tissue Acquisition: Meta-Analysis Comparing the Procore and Standard FNA Needles Ji Young Bang*, Muhammad Hasan, Robert Hawes, Shyam Varadarajulu Center for Interventional Endoscopy, Florida Hospital, Orlando, FL Background: To overcome the limitations associated with cytology, a ProCore biopsy platform has been developed in 19, 22 and 25G sizes. However, individual studies Vol comparing the ProCore and FNA needles have yielded varying conclusions. Purpose of the Study: This meta-analysis was conducted to compare the performance of the ProCore and standard FNA needles when performing EUS-guided tissue acquisition. Methods: All published manuscripts and presented abstracts (International Scientific Meetings) that compared the ProCore and FNA needles were analyzed. Excluded were non-comparative and technical feasibility studies. Main outcome measures: Compare the rates of diagnostic adequacy, diagnostic accuracy, histological core tissue procurement and mean number of passes to diagnosis when sampling all solid organ lesions and solid pancreatic masses. Results: A total of 21 studies involving 1617 patients met inclusion criteria. There was significant heterogeneity in study design and end points. Study outcomes are shown in the Table. There was no significant difference in diagnostic adequacy/accuracy, histological core tissue procurement or mean number of passes to diagnosis between both cohorts. Subgroup analysis did not reveal any difference between the 19, 22/25G needles for any of the outcome measures. Conclusions: Current data does not demonstrate a significant difference in performance between the ProCore and standard FNA needles for establishing a diagnosis with fewer no. of passes, for yielding a better cytological aspirate or histological core tissue. Therefore, the choice of a needle should be based on endosonographer preference and needle costs.