The value of endorectal elastography in the diagnosis of malignant rectal adenoma / 中华医学超声杂志（电子版）

ABSTRACT

Objective To assess the value of endorectal elastography in the diagnosis of malignant rectal adenoma. Methods Sixty patients referred to the department of basic surgery of Peking Union Medical College Hospital for the evaluation of rectal adenoma from January 2011 to May 2013 were included in this prospective cohort. All patients underwent elasticity score (ES) and strain ratio(SR) examine before operation. To evaluate the reproducibility of the strain-ratio measurements, the intraclass correlation coefficient (ICC) was calculated. Compared with final operational pathological results,the diagnostic values of elasticity score and strain ratio method were assessed. Results Histopathological result showed there were 20 adenomas and 40 adenocarcinomas. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of ERUS was 68%(27/40), 40%(8/20), 58%(35/60), 69%(27/39), 38%(8/21), respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of elasticity score was 85%(34/40), 70%(14/20), 80%(48/60), 85%(34/40), 70%(14/20), respectively. The SR of adenocarcinomas was significantly higher than that of adenomas(2.82±1.81 vs 1.23±0.57, t=3.333, P < 0.05). The differences among the SR of benign adenoma, benign adenoma with severe atypical hyperplasia and completely malignant lesions were statistically significant (1.26±0.84 vs 2.94±1.95, 1.42±0.55 vs 2.94±1.95, t=2.619, 2.415, P=0.013, 0.021). When 1.240 was chosen as the best cut-off value of SR, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of strain ratio was 82%(33/40), 75%(15/20), 80%(48/60), 87%(33/38), 68%(15/22), respectively. Conclusion Endorectal elasotgraphy can accurately diagnose the malignant rectal adenoma, which can provide reliable preoperative imaging evidence for clinical operation mode.