The usage of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for the diagnosis of solid pancreatic cancer is increasing, however mainly retrospective studies are available about the detailed methods of sampling. To compare prospectively the diagnostic yield of EUS-FNA samples obtained with slow-pull (SP) and with standard suction technique (SS). EUS-FNA sampling was diagnostic in 72 of 92 cases (78.3%). Diagnostic yield was 67.4% in the SS and 65.2% in the SP group. The number of smear pairs (1.84 vs. 3.56; p < 0.001) and blood contamination (1.50 vs. 2.19; p < 0.001) were significantly higher in the SS group, which resulted in lower rate of diagnostic samples (41.8% vs. 30.0%; p = 0.003). There was no difference in the cellularity (1.58 vs. 1.37; p = 0.2554), or in the sensitivity and specificity in the identification of malignancy between SP and SS subgroups (69.9, 100% vs. 73.5, 100%). Histological samples were obtained in 60 cases (with SP: 49 cases; with SS: 46 cases). There was no difference in the diagnostic yield of histological samples between the groups (63 and 58.7%). The diagnostic yield, the cellularity of smears and the rate of acquiring sufficient histological material are similar in the SP and SS group, but due to lower bloodiness and decreased number of slides, the pathological diagnosis is faster and more cost-effective.

Background: The inconclusive cytological findings of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) remain a major clinical challenge and often lead to treatment delays. Methods: Patients who had undergone EUS-FNA sampling for solid pancreas lesions between 2014 and 2021 were retrospectively enrolled. The “atypical” and “non-diagnostic” categories of the Papanicolaou Society of Cytopathology System were considered inconclusive and the “negative for malignancy” category of malignancy was suspected clinically. We determined the frequency and predictors of inconclusive cytological finding. Results: A total of 473 first EUS-FNA samples were included, of which 108 cases (22.83%) were inconclusive. Significant increases in the odds of inconclusive cytological findings were observed for lesions with a benign final diagnosis (OR 11.20; 95% CI 6.56–19.54, p < 0.001) as well as with the use of 25 G FNA needles (OR 2.12; 95% CI 1.09–4.01, p = 0.023) compared to 22 G needles. Furthermore, the use of a single EUS-FNA technique compared to the combined use of slow-pull and standard suction techniques (OR 1.70; 95% CI 1.06–2.70, p = 0.027) and less than three punctures per procedure led to an elevation in the risk of inconclusive cytology (OR 2.49; 95% CI 1.49–4.14, p < 0.001). Risk reduction in inconclusive cytology findings was observed in lesions between 2–4 cm (OR 0.40; 95% CI 0.23–0.68, p = 0.001) and >4 cm (OR 0.16; 95% CI 0.08–0.31, p < 0.001) compared to lesions ≤2 cm. Conclusions: The more than two punctures per EUS-FNA sampling with larger-diameter needle (19 G or 22 G) using the slow-pull and standard suction techniques in combination may decrease the probability of inconclusive cytological findings.

Diagnostic accuracy and quality of smears obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) are influenced by characteristics of suction and examined organ. Efficiency of EU...