经直肠腔内超声对直肠神经内分泌肿瘤的诊断价值

Diagnostic value of endorectal ultrasound in the rectal neuroendocrine neoplasm

目的探讨直肠神经内分泌肿瘤(R-NEN)的经直肠超声(ERUS)图像特点,比较ERUS与MRI对R-NEN的诊断效能。方法回顾性分析2015年8月至2021年8月于中山大学附属第六医院77例经病理证实为R-NEN患者的ERUS图像特点,比较不同病理分级R-NEN超声表现的差异,并比较ERUS与MRI检查对R-NEN进行T分期的能力。结果共收集77例术前行ERUS检查的R-NEN患者,其中62例检出病灶,检出率为80.52%。同时进一步行MRI检查者共30例,25例检出病灶,检出率为83.33%。R-NEN在ERUS主要表现为黏膜下层血流丰富的低回声结节。不同病理分级R-NEN的ERUS表现具有一定的特征性,G1级及G2级肿瘤大小一般小于10 mm,边界清楚,形态规则;G3级肿瘤一般较大,形态不规则,边界欠清,更容易侵犯固有肌层及浆膜层。经过比较发现,G3级较G1级、G2级的浸润深度更深,边界更为不清,病灶更大,上述差异有统计学意义(均P<0.05)。比较ERUS及MRI对T分期的判断能力,ERUS分期准确性为86.67%,MRI为94.67%,差异无统计学意义(P>0.05)。结论ERUS不但可有效检出R-NEN病灶,且影像特点对肿瘤分级具有一定参考价值,T分期诊断能力可与MRI检查相媲美,是R-NEN术前诊断的有效检查方法。

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.