2008 Annual Meeting Abstracts
Distal Margins in Radical Resections for Rectal Cancer after Chemoradiation Therapy: How Short is Long Enough?
Victor E. Pricolo, MD, Adam Abodeely, MD, Mark Legolvan, MD, Murray Resnick, MD.
Rhode Island Hospital, Brown Univ., Providence, RI, USA.
Objective: To assess the impact of distal resection margins length on outcome in patients with rectal cancer treated with neo-adjuvant chemoradiation therapy (CRT), followed by radical proctectomy with total mesorectal excision.
Design: Cohort case series.
Setting: Tertiary care academic medical center.
Patients: Fifty-two consecutive patients (36 males, 16 females) aged 39-85 years, were evaluated. Selection criteria included: biopsy proven adenocarcinoma of the mid- or distal rectum; locally advanced tumor stage (uT3-4 N0-1); absence of distant metastases; preoperative CRT followed by radical proctectomy.
Interventions: Pre-treatment tests included colonoscopy, endorectal ultrasound/CT/MRI, CEA level. Proctoscopy was done before CRT and 3-4 weeks after its completion, before surgical intervention. Mean CRT to surgery interval was 45 days. Operations included low anterior resection (LAR) in 33 patients (63%) and abdomino-perineal resection in 19 (37%), depending on tumor location, extent and endoscopic regression. Mean follow-up was 32.7 months.
Main Outcome Measures: Tumor regression; complete pathologic response (cPR=ypT0N0); length of distal resection margins; status of radial margins; local recurrence rate.
Results: Tumor regression was observed in 48 patients. Eleven patients (21%) had a cPR. All patients had tumor-free distal resection margins, (length 0.1-7.4 cm; mean=2.2 cm). In stapled LAR patients, all distal donuts were also negative. Two patients had positive radial margins. Follow-up was current in 49 patients (94%). No patient has had a loco-regional recurrence to date.
Conclusions: In radical proctectomy, distal resection margins shorter than 1-2 cm may be adequate in patients who underwent preoperative CRT. These findings could broaden use of sphincter-saving procedures. Validation of these data would require larger sample size and longer follow-up. Distal margins length may be less relevant than other variables in rectal cancer therapy.