Background: There is a lack of prospective, randomized studies comparing the diagnostic yield and complication rates of 22-gauge and 25-gauge needles during EUS-FNA of solid pancreatic masses.
Objectives: Our primary aim was to compare the diagnostic yield of 22-gauge and 25-gauge needles. Secondary aims included determining the number of needle passes performed, ease of needle passage, and complications.
Design: Prospective, randomized study.
Setting: Tertiary referral centers at Yale University School of Medicine, New Haven, Connecticut, and Virginia Piper Cancer Institute, Minneapolis, Minnesota.
Patients: Patients with a suspected solid pancreatic mass from February 2007 to June 2008 were enrolled.
Interventions: Patients were randomized to EUS-FNA with a 22-gauge or 25-gauge needle.
Main outcome measurements: A diagnostic result was defined as cytology findings positive for malignant cells.
Results: A total of 131 patients were enrolled: EUS-FNA was performed with a 22-gauge needle in 64 patients and with a 25-gauge needle in 67 patients. Cytology was diagnostic in 120 (91.6%) of 131 patients overall: 56 (87.5%) of 64 with 22-gauge needles and 64 (95.5%) of 67 with 25-gauge needles (no statistically significant difference was found between the 2 groups; P=.18). A similar number of passes was performed in both arms (mean [SD] 2.6 [1.2] each; P=.96). There were no complications in either group.
Limitation: A larger number of patients is needed to determine small differences in diagnostic yield.
Conclusions: This is the first prospective, randomized trial comparing 22-gauge and 25-gauge needles in EUS-FNA of solid pancreatic masses. We achieved equally high diagnostic yields by using a similar number of passes, showing that 25-gauge needles are an effective alternative to 22-gauge needles.