Effectiveness of endoluminal sonography in the identification of occult local rectal cancer recurrences

PURPOSE: Local recurrence of rectal cancer after curative surgery appears in 5 to 30 percent of all cases. It is necessary to detect local recurrence in a resectable stage to have an opportunity for currative reintervention or palliative prevention of those symptoms. Because most local recurrences occur extraluminally, conventional follow-up fails to detect them at an early stage. Therefore, a prospective study was performed to assess the diagnostic potential of endorectal and endovaginal ultrasound to detect asymptomatic resectable local recurrence. METHODS: In 338 patients 721 endoluminal ultrasound examinations were added to routine follow-up of rectal and left colonic cancer, with a mean of 2.1 (range, 1–10) endoluminal ultrasound examinations for each patient. RESULTS: A total of 116 patients (34.3 percent) were shown to have local recurrence, which was suggested by endoluminal ultrasound and proven by endoluminal ultrasound-guided needle biopsy in all cases of unclear pararectal structures that could not be verified by endoscopic biopsy. Digital examination failed to detect local recurrence in 91 patients, endoscopy failed to detect local recurrence in 80 patients, and the levels of tumor markers were normal in 25 patients with confirmed local recurrence. In 33 cases of local recurrence, both digital examination and endoscopy results were normal. Twenty-five patients, in whom carcinoembryonic antigen levels, digital examination, and endoscopy results were normal, underwent potential curative reoperation, with total resection of the local recurrence. All 25 patients were still alive at the end of the study period, and 21 were free from disease. On the other hand, only 6 of 67 patients with local recurrence detectable by conventional follow-up could be operated on with curative intention. CONCLUSION: Postoperative endoluminal ultrasound is able to detect local recurrence at an earlier and asymptomatic stage and can be verified by endosonography-guided needle biopsy. Routine use in follow-up may raise the ratio of curative retreatment by early detection of extramural local recurrence.