Site of puncture in endoscopic ultrasound‐guided fine needle biopsy: Does it change diagnostic outcome?

We read with great interest the study by Ko et al.,1 comparing diagnostic outcomes according to puncture sites in endoscopic ultrasound (EUS)-guided fine needle biopsy (FNB) for pancreatic lesions >3 cm. Sampling from the center and periphery of lesions showed equivalent diagnostic accuracy in detecting malignancy. However, when samples from both locations were combined, the diagnostic yield was higher than samples from either of the locations alone. Although the study adds to the currently limited literature on this topic, a few issues need to be addressed. First, the lesions were punctured, alternating between the periphery and the center, allowing tissue acquisition from multiple sites within the lesion. In the fanning technique also, after the initial puncture, the trajectory of the needle is altered using either the big wheel or elevator in the endoscope, allowing tissue acquisition from multiple sites within the lesion.2 Thus, the present technique seems like a variation of the fanning technique rather than a novel one. A recent trial reported that the fanning technique has a diagnostic utility comparable to contrast-guided FNB.3 Thus, the authors need to explain how the present technique is different and superior to the fanning technique. Second, dry suction was used for all patients in the present study. In a previous meta-analysis, wet suction was shown to be slightly better than other suction methods.4 Therefore, it is possible that combining wet suction with this method could have improved the diagnostic outcome. Third, the EZ Shot 3 needle is a fine-needle aspiration rather than a biopsy needle. Lastly, the effect of macroscopic on-site evaluation on the diagnostic outcome could not be evaluated.5 Although the present study adds to the evolving techniques for improving diagnostic outcomes of EUS-FNB, further studies are required to validate the present study's findings. Author declares no conflict of interest for this article.