Factors for the accuracy of endoscopic ultrasound fine needle aspiration (EUS-FNA) of solid pancreatic masses-a real life analysis in a newly established gastrointestinal center

Aim:

to investigate the factors which influence the accuracy and sensitivity (Se) of EUS-FNA of solid pancreatic masses.

Methods:

87 Patients with 96EUS-FNA of solid pancreatic masses performed between 2014 – 2018 were enrolled in this retrospective study. Final diagnosis was establish by histopathology, surgery, radiological findings, and clinical follow-up.

Positive EUS-FNA was defined as the finding of at least atypical cells with dysplasia.

Per definition, an experienced endosonographer has performed at least 150 EUS including 50 interventions.

Results:

The mean age of patients was 66.6 ± 13.5 years. The most common final diagnosis was adenocarcinoma (66.6%), following by inflammation (9.2%), neuroendocrine tumors (8.1%). The overall accuracy was 65.6%, with lowest value in 2016 (27.2%) and highest value in 2018 (79.3%).

Overall Se for detecting malignancy was 56%, with lowest value in 2016 (27.2%) and highest value in 2018 (76%).

Endosonographer experience seems to influence the accuracy as well the Se of FNA. There was a significant difference in favour of 19G vs. 22G needle: 66.6% vs. 36.3%, p = 0.03. EUS-FNA of the larger lesions were more accurate in comparison to the smaller pancreatic masses (Table).

Tab. 1

Factor Size:< 2 cm (A) vs. 2 – 4 cm (B) vs. > 4 cm (C)	Sensitivity (%) 50% vs. 51.9% vs. 76.9% A vs. B: p = 0.81 A vs. C: p = 0.36 B vs. C: p = 0.18	Accuracy (%) 61.5% vs. 59.7% vs. 82.3% A vs. B: p = 0.85 A vs. C: P = 0.39 B vs. C: p = 0.14
Localisation: Uncinate (A) vs. Head (B) vs. Body (C) vs. Tail (D)	57.1% vs. 53.8% vs. 53.8% vs. 66.6% A vs. B: p = 0.92 A vs. C: p = 0.82 A vs. D: p = 0.98 B vs. C: p = 0.74 B vs. D: p = 0.74 C vs. D: p = 0.87	63.1% vs. 60.7% vs. 61.1% vs. 72.7% A vs. B: p = 0.92 A vs. C: p = 0.83 A vs. D: p = 0.89 B vs. C: p = 0.80 B vs. D: p = 0.68 C vs. D: p = 0.81
Needle: 19 Gvs. 22 G	64.1% vs. 36.3% p = 0.04	70% vs. 48.1% p = 0.06
Stent in the main biliary duct: yes vs. no	56.2% vs. 55.9% p = 0.79	64.2% vs. 64.7% p = 0.72
Trainee vs. experienced	47.2% vs. 64.1% p = 0.18	57.4% vs. 70% p = 0.20

Conclusion:

Endosonographer experience, needle size and size of pancreatic lesion seems to influence the accuracy and Se of EUS-FNA. We observed an overall accuracy and Se lower than reported by high volume centers, but with a significant improvement with increasing operator experience.