Surgical treatment of rectal cancer: results of a strategy for selective preoperative radiotherapy.

Aim: The indications for preoperative adjuvant therapy in rectal cancer are still a subject of debate. The objective of this study was to analyze the results of surgical resection and selective radiotherapy in a group of high-risk patients (Dukes B and C) taken from a series of 148 consecutive patients with rectal cancer.

Methods: All patients with rectal cancer considered for resection during the period 1994-2004 were prospectively included. The policy was to deliver preoperative radiotherapy in cases of fixed or tethered tumors or when imaging predicted T3 tumors with positive circumferential margins. Other tumors were resected without neoadjuvant therapy. All resections were done using the total mesorectal excision (TME) technique.

Results: One hundred and forty-eight consecutive patients underwent rectal resection during the study period. A sphincter-saving technique was carried out in 134 patients (90%). No patient was excluded from the analysis. The perioperative mortality was 2/148 (1.5%). Curative surgery was obtained in 135 patients. The 94 patients with a Dukes B or C tumor formed the high-risk group that was the basis of our study. The mean follow-up in this group was 58 months (range 24-120). Twenty patients (21%) received preoperative radiotherapy (PRT) and 74 (79%) underwent surgical resection alone. A positive circumferential margin, defined as one that was < or =1 mm, was found in seven of the 85 patients (8.2%) for whom this measure was available. The actuarial five-year overall survival was 74%. Local recurrence developed in eight patients (8.4%): four in the PRT group (20%), and four in the non-PRT group (5.4%). Only two patients developed an isolated local recurrence.

Conclusions: Preoperative adjuvant therapy can be safely omitted in patients who demonstrate clear circumferential margins on preoperative imaging, provided that adequate surgery is subsequently performed.