The feasibility and safety of trans-colorectal endoscopic ultrasound-guided fine-needle aspiration: a retrospective study of Japan

Background/Aims: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is an effective diagnostic technique; however, few studies have evaluated the efficacy of trans-colorectal EUS-FNA. This study assessed the feasibility of trans-colorectal EUS-FNA. Methods: We retrospectively analyzed 76 consecutive patients who underwent trans-colorectal EUS-FNA for pelvic lesions between January 2013 and September 2023. Results: A total of 76 pelvic lesions were identified. The median number of EUS-FNA punctures was 3 (1–8). The median lesion size was 18.9 (8.2–100.0) mm. The success rate was 98.7% (75/76), with no reported adverse events. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EUS-FNA were 94.3% (50/53), 100% (22/22), 100% (50/50), 88.0% (22/25), and 96.0% (72/75), respectively. Malignancy was initially suspected in 65 patients before EUS-FNA; however, 25 patients showed benign re-sults. Of these, three were later reexamined and diagnosed with malignancy, three underwent surgery and were found to have benign pathology, and 19 avoided unnecessary surgery. Conclusions: Trans-colorectal EUS-FNA is a safe and effective diagnostic procedure.