PREOPERATIVE STAGING OF RECTAL-CANCER BY ENDOLUMINAL ULTRASOUND VS MAGNETIC-RESONANCE-IMAGING PRELIMINARY-RESULTS OF A PROSPECTIVE, COMPARATIVE-STUDY

PURPOSE: The aim of this study was to compare the value of endoluminal ultrasonography (ELUS) with magnetic resonance imaging (MRI) for preo perative staging of rectal carcinoma. METHODS: Thirty-seven consecutiv e patients were examined by ELUS and MRI. imaging results were compare d with pathohistologic studies. A tumor extending beyond the bowel wal l was considered to be ''positive'' and one within the bowel wall was considered ''negative.'' Lymph node involvement was considered present if nodes equal to or greater than 5 mm in diameter were found in the perirectal tissue. For evaluating the differences between the two meth ods, the Me Nemar test was performed. RESULTS: T-Staging was correct i n 88.2 percent (30/34) of patients by ELUS and in 82.3 percent (28/34) by MRI (difference not significant). N-Staging was correct in 80 perc ent (20/25) by ELUS and in 60 percent (15/25) by MRI (difference of bo rderline significance). A comprehensive preoperative staging (T + N) w as made correctly in 68 percent (17/25) by ELUS and in 48 percent only (12/25) by MRI (difference not significant). CONCLUSIONS: We suggest that ELUS and MRI must be evaluated within the framework of establishe d parameters when treatment modalities such as preoperative radiation therapy and local or radical surgical approach must be decided.