The aims of this prospective study were 1) to evaluate the accuracy of high−resolution three−dimensional endorectal ultrasonography in distinguishing slight from massive submucosal invasion of early rectal tumors, and 2) to determine the technology's role in treatment selection.

A total of 142 consecutive patients with clinically possible pT1 rectal cancers underwent three−dimensional endorectal ultrasonography. Slight or massive irregularity of the hyperechoic submucosal layer was considered to characterize uT1−slight or uT1−massive tumors. Treatment was selected on the basis of ultrasonographic findings: endoscopic resection or full−thickness transanal local excision was selected for uT1−slight lesions, and radical resection was selected for uT1−massive tumors. Ultrasonographic staging was compared with histopathologic staging.

One hundred twenty−six patients were included in the final analyses. Three−dimensional endorectal ultrasonography staged 77 lesions as uT0, 25 as uT1−slight, 20 as uT1−massive, and 4 as uT2. Histologically, adenomas were found in 75 patients and tumor invasion was found in 44 lesions (24 pT1−slight, 16 pT1−massive, 4 pT2). The overall kappa for the concordance between ultrasonographic and histopathologic stagings was 0.81 (95% confidence interval, 0.72−0.89). No invasive carcinomas remained undetected. The depth of invasion was correctly determined in 87.2% of both pT1−slight and pT1−massive lesions. Considering the complete series of 126 patients, the accuracy of this modality in selecting appropriate management was 95.2% (kappa, 0.84; 95% confidence interval, 0.71−0.96). Adequate surgery was performed in 87.5% of pT1 tumors.

Three−dimensional endorectal ultrasonography is useful for assessing the depth of submucosal invasion in early rectal cancer and for selecting therapeutic options.

PMID: 19966629 [PubMed − indexed for MEDLINE] Source: National Library of Medicine.