Linear array ultrasonography to stage rectal neoplasias suitable for local treatment

Abstract

Background: Because of the many therapeutic options available, a reliable staging is crucial for rectal neoplasia management. Adenomas and cancers limited to the submucosa without lymph node involvement may be treated locally.

Aims: The aim of this study is to evaluate the diagnostic accuracy of endorectal ultrasonography in the staging of neoplasias suitable for local treatment.

Methods: We considered all patients who underwent endorectal ultrasonography between 2001 and 2010. The study population consisted of 92 patients with 92 neoplasias (68 adenocarcinomas and 24 adenomas). A 5 and 7.5MHz linear array echoendoscope was used. The postoperative histopathologic result was compared with the preoperative staging defined by endorectal ultrasonography. Adenomas and cancers limited to the submucosa were considered together (pT0-1).

Results: The sensitivity, specificity, overall accuracy rate, positive predictive value, and negative predictive value of endorectal ultrasonography for pT0-1 were 86%, 95.6%, 91.3%, 94.9% and 88.7%. Those for nodal involvement were 45.4%, 95.5%, 83%, 76.9% and 84%, with 3 false positive results and 12 false negative. For combined pT0-1 and pN0, endorectal ultrasonography showed an 87.5% sensitivity, 95.9% specificity, 92% overall accuracy rate, 94.9% positive predictive value and 90.2% negative predictive value.

Conclusion: Endorectal linear array ultrasonography is a reliable tool to detect rectal neoplasias suitable for local treatment.