TRANSRECTAL ULTRASONOGRAPHY AND OPERATIVE SELECTION FOR EARLY CARCINOMA OF THE RECTUM

BACKGROUND: Transrectal ultrasonography (TRUS) supplements clinical ev aluation of early carcinoma of the rectum in selecting patients for lo cal operative therapy, such as transanal excision (TAE). STUDY DESIGN: This study was done to evaluate the accuracy of ultrasonographic stag ing of tumor depth (T stage) in patients with suspected early carcinom a of the rectum, to compare ultrasonographic with clinical T-staging a ccuracies within this patient group, to determine if any specific tumo r characteristics (configuration, size, location) predispose toward ul trasonographic T-staging inaccuracy, and to examine the role of TRUS i n operative selection for patients with early carcinoma of the rectum. RESULTS Between April 1990 and December 1992, 62 patients with primar y carcinoma of the rectum underwent ultrasonographic staging (uT), whe reby three uT(4), 27 uT(3), 24 uT(2) and eight uT(1) carcinomas were i dentified. Of the 32 patients with suspected intramural (uT(1) or uT(2 )) disease, 27 underwent prompt operative excision or resection at our institution, allowing comparative histopathologic staging. in this hi ghly selected patient subset, uT(1) staging was correct in all instanc es; uT(2) staging was incorrect in 45 percent of instances, with 30 pe rcent having unpredicted transmural penetration. Ultrasonographic and clinical staging accuracies were quantitatively similar, and no tumor characteristics were consistently associated with ultrasonographic imp recision. CONCLUSIONS: Among patients with clinically suspected early carcinoma of the rectum, the decision to perform TAE is supported by u ltrasonographic T-1 staging. By contrast, the decision to perform TAE cannot be based solely on ultrasonographic T-2 staging, because of the possibility for transmural penetration of tumor.