Can preoperative radiotherapy be alternative therapy in place of lateral lymph node dissection for patients with advanced carcinoma of the distal rectum?

To clarify whether radiotherapy can be alternative therapy in place of lateral lymph node dissection (LLND), a retrospective study on patients with advanced carcinoma of the distal rectum undergoing curative operation with LLND was conducted. Fifty-one patients received preoperative high-dese extracorporeal (30-40 Gy) and endocavitary (30-40 Gy) radiation therapy (total 60-70 Gy), and 84 patients underwent surgical resection alone. The lateral lymph node metastasis was significantly associated with local recurrence (p<0.005). The nodal involvement was significantly different in perirectal region between radiation group and surgery alone group (27.5% vs 57.1%, p<0.005), but not in lateral region (9.8% vs 15.5%, no significance (n.s.)). The mode of LLND marginally affected the local recurrence in patient without radiotherapy (23.2% in sampling group vs 8.9% in dissection group, p=0.08). Local disease free survival was not different between radiotherapy group and surgery alone group. This study suggests that it is not recommended for patients with advanced distal rectal carcinoma to alternate the preoperative high-dese extracorporeal and endocavitary radiation therapy in place of LLND. (author)