Diagnostic value of endorectal ultrasound in the rectal neuroendocrine neoplasm / 中华超声影像学杂志

ABSTRACT

Objective:To investigate the endorectal ultrasound findings in rectal neuroendocrine neoplasms (R-NEN) and to compare the diagnostic performance of ERUS and MRI for T staging of R-NENs.Methods:The imaging features of 77 confirmed R-NEN cases with different pathological grades in the Sixth Affiliated Hospital, Sun Yat-sen University from August 2015 to August 2021 were retrospectively analyzed and the abilities of ERUS and MRI for T staging of R-NENs were compared.Results:A total of 77 R-NEN patients underwent preoperative ERUS examinations and detected lesions in 62 patients with a detection rate of 80.52%. Among them, 30 cases underwent simultaneous MRI examinations, and detected lesions in 25 cases with a detection rate of 83.33%, without statistical difference between MRI and ERUS ( P>0.05). R-NEN exhibited hypoechoic nodules with rich blood flow in the submucosa on ERUS. Grade G1 and G2 tumors generally had sizes less than 10 mm, clear boundaries, and regular shapes, while G3 was typically large, irregular, poorly defined, and more likely to invade the musculi propria and serous layer. G3 demonstrated a more profound infiltration level, a less defined border, and a larger diameter than G1 and G2, with statistically significant differences (all P<0.05). For T staging, the accuracy of ERUS was 86.67%, and that of MRI was 94.67%, with no statistical difference ( P>0.05). Conclusions:ERUS is effective for detecting R-NEN lesions and useful for tumor grading with comparable performance to MRI, and should be recommended for preoperative evaluation of neuroendocrine tumors.