The 2nd Department of Surgery, Hirosaki University School of Medicine
Ultrasonography, Intrarectal linear scanning, Perineal linear scanning, Rectal cancer, Depth of invasion of cancer
We designed two new approaches of ultrasonic examination through perineal and intrarectal linear scanning with intravisceral probe and ultrasonic endoscope in diagnosis of rectal cancer. The intrarectal scanning with water enema was performed in 26 patients (25 with rectal cancer, one with cancer of sigmoid clon), and the perineal scanning with water enema or intrarectal balloon technique was done in 37 patients (35 with rectal cancer, 2 with anal cancer). Delineation rate of tumor by intrarectal scanning was 100% and that by perineal scanning was 75.7%. The normal rectal wall was composed of 5 layers on the ultrasonogram. The depth of invasion of cancer to the rectal wall was correctly diagnosed in 17 out of 26 patients by intrarectal scanning and in 18 out of 37 patients by perineal one. Local recurrence was detected by intrarectal scanning in 3 cases after sphincter preserving operations. The metastasis to local lymphnode was shown as a hypoechoic round area and was correctly diagnosed in 4 out of 9 patients. From these results, it might be thought that ultrasonic examination through intrarectal and perineal scanning provided a valuable information for diagnosis of the depth of invasion, local lymphnode metastasis and recurrence in rectal cancer.