Lateral resection margin as a prognostic factor in rectal cancer

The study included 71 patients with resectable rectal cancer who underwent total mesorectomy during 2000-2007. The median follow-up period was 24 months (range: 14 to 63). The distance from the tumor to the lateral resection margin of the rectum varied from 0 to 20 mm (medium 5mm). Involvement of the lateral resection margin (≤1 mm) was found in 6 patients (8,4 %). None of them developed local recurrences, whereas 4 (66,7 %) patients died of distant metastases. In 18 patients the distance from the tumor to the lateral resection margin was ≤3,0 mm. No significant difference in the incidence of local recurrence between patients with the distance from the tumor to the lateral resection margin ≤ 3,0 mm and > 3 mm was found (5,5 % versus 3,7 %). Distant metastases were found in 38,9 % and 7,5 % of patients, respectively (OR 0,66 [95 % CI: 0,45-0,96]; p=0,002). Statistically significant differences were found in terms of 5-year recurrence-free survival rates (30,4 ± 22,5 % and 86,7 ± 5,7 %, respectively, p=0,011). The distance from the tumor to the lateral resection margin of ≤3,0 mm is an adverse factor of long-term survival and distant metastasis in patients with resectable rectal cancer. These patients are recommended to receive prolonged radiotherapy in combination with chemotherapy and probably with the target therapy.