THE INFLUENCE OF THE NUMBER OF LYMPH NODES UPON SURVIVAL RATES IN COLORECTAL CANCER

One hundred and ninety-four colorectal cancer patients (colon cancer 111, rectal cancer 83) who underwent a curative resection were analized in order to evaluate the influence of the number of dissected lymph nodes upon the postoperative long-term survival rate. The tumor depth of invasion was pm or more in all cases, but none had distant metastasis before surgery. In colon cancer, the group of cases with 20 or more dissected lymph nodes showed better 5-year survival rate than that with 10 or less lymph nodes dissected though the degree of lymph node dissection is the same between both groups (p<0.05). Between the cases with the tumor depth of invasion “s” and those of “ss” in colon cancer having no lymph node metastasis, no stastistical significant difference was observed in 5-year survival rate. Furthermore, the maximal diameters of the serosal invasion showed a statistical difference between the group that lived for over 5 years and the group that died within 2 years postoperatively. Accordingly, it seems likely that the number of dissected lymph nodes has an important significance for the postoperative local recurrence in colon cancers. On the other hand, no relationship was found between the number of dissected lymph nodes and the postoperative long-term survival rate in rectal cancers. Other factors rather than the lymph node metastasis may be responsible for the local recurrence in rectal cancers.