Reply to Lévy et al.

Abstract

We appreciate the interest of Dr. Lévy and colleagues [1] in our report [2]. We agree that endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) should be performed to direct clinical management, meaning FNA results will affect surgical decision making. Our purpose in publishing this multicenter experience was twofold: (i) to increase awareness in the EUS community of this very rare entity, the solid pseudopapillary tumor (SPT), and (ii) to evaluate, we emphasize, the diagnostic accuracy of EUS-FNA in making a definitive diagnosis, as compared to surgical pathology. The key word here is ”diagnostic.” No patient in the series was referred with a pre-EUS suspicion of an SPT, and SPT was included in the differential diagnosis on the EUS report in only 50 % of cases in our series. Thus it was considered, but not necessarily suspected. This tumor is frequently misdiagnosed as a neuroendocrine tumor preoperatively. In the study by Bardeles et al., 50 % of the cases were diagnosed as neuroendocrine tumors based upon the EUS appearance [3]. In our series, five patients were diagnosed with neuroendocrine tumors by EUS-FNA cytology and immunostaining (as immunostains specific for SPT were not performed). Hence, our purpose herein of increasing awareness and recommending immunostain profiles when this lesion is considered, which will increase the diagnostic accuracy.