ASSESSING THE EFFECTIVENESS OF MESORECTAL EXCISION IN RECTAL-CANCER -PROGNOSTIC VALUE OF THE NUMBER OF LYMPH-NODES FOUND IN RESECTED SPECIMENS

PURPOSE: The aim of this study was to determine whether the number of involved or uninvolved lymph nodes in resected specimens can be used t o predict the effectiveness of surgical resection for rectal cancer. M ETHODS: Local recurrence and survival rates for 118 patients undergoin g curative resection for rectal carcinoma, without adjuvant therapy, w ere retrospectively studied. RESULTS: Mean follow-up was 62 +/- 37 mon ths. Mean number of involved or uninvolved lymph nodes per resected sp ecimen was 12 +/- 7. Overall local recurrence rate was 15.2 percent. I n patients without involved lymph nodes (NO patients) and with T1 or T 2 tumors, the local recurrence rate ranged from 0 to 8 percent (not si gnificant), depending on the number of lymph nodes on the specimen. In patients without involved lymph nodes and those with T3 tumors, the a ctuarial survival rate at ten years was significantly lower (P < 0.05) , and the local recurrence rate was higher (P < 0.02) in patients with fewer than ten lymph nodes than in those with more than ten nodes. In patients with involved lymph nodes, the mean number of nodes on the r esected specimen correlated closely with the mean number involved by t he tumor. CONCLUSION: The assessment of the effectiveness of rectal ex cision for cancer is in part helped by the number of involved or uninv olved lymph nodes found on the resected specimen. This is of particula r interest in patients without involved lymph nodes and those having i nfiltrating T3 tumors, for whom the long-term survival and local recur rence rates were significantly better when more than ten lymph nodes w ere present. On the other hand, when fewer than ten nodes were found, whatever the cause, adjuvant radiotherapy had to be considered, becaus e of the high risk of local failure rate.