The expanding utility of endoluminal ultrasonography in the management of rectal cancer.

Overview

BACKGROUND: This study assessed the ability of endoluminal ultrasonography (ELUS) to determine extent of local invasion and lymph node (LN) metastasis of primary rectal tumors, to assist in ELUS-guided pelvic LN biopsies, and to assess invasion of locally recurrent rectal cancers compared to computed tomography (CT). METHODS: Eighty-one patients with rectal adenocarcinoma (n = 67) or villous adenoma of more than 3 cm (n = 14) underwent ELUS with a 360-degree 7.0-MHz transducer For LN biopsy (n = 10), ELUS was used with an 18-gauge core biopsy needle passed transrectally. ELUS and CT were compared in 14 locally recurrent tumors. RESULTS: Staging for primary tumors (ELUS compared with pathologic examination, TNM system) revealed ELUS accurately predicted wall penetration and LN status with 95% confidence intervals of 0.88 to 0.99 and 0.87 to 0.99. Eight cancers were overstaged, and two were understaged by ELUS. ELUS-guided LN biopsy revealed carcinoma (n = 3) or lymphoid tissue (n = 3) in six of 10 patients. Extent of pelvic organ involvement was predicted in 11 of 14 ELUS and eight of 14 CT examinations in recurrent rectal cancer. CONCLUSIONS: ELUS is accurate in staging rectal cancers, can guide biopsies of pararectal LNs, and may be more reliable than CT in assessing local recurrence. The role of ELUS in the management of rectal cancer is expanding.