Abstract
Purpose: We studied the clinical significance of direct invasion to adjacent organs in locally advanced colorectal cancer. Method: Subjects were 323 consecutive patients who underwent curative surgery for colorectal carcinoma, pT3-4, from 1992 to 1998. We studied the relationship of pathologic invasion to adjacent organs of tumors to other clinicopathological factors and its contribution to prognosis in clinical staging. Results: Of the 323 pT3-4 tumors, 28 (8.7%) showed pathologically defined invasion to adjacent organs (pT4). A significant difference was seen in tumor size, frequency of mulivisceral resection and blood transfusion, operative blood loss, and operation time between pT3 and pT4 tumors (p<0.0001). Patient survival of pT4 tumors was almost the same as that of pT3 tumors in JGR stage II-IIIa tumors (n=261)(p=0.9591). However, a significant difference was seen in patient survival when they were divided by lymph node status (p<0.0487). No difference was observed when survival of patients with a TNM stage II tumor (n=177) that was node-negative was compared between stage IIA (pT3) and IIB (pT4)(p=0.8069). Multivariate analysis showed that only lymph node metastasis (p=0.0043) and blood transfusion (p=0.0223) were significant prognostic factors in patient survival in pT3-4 colorectal cancer. Conclusion: Pathological invasion to adjacent organs is less significant than lymph node metastasis as a prognostic factor in locally advanced colorectal cancer after curative resection. It significantly affects perioperative factors and patient prognosis may be worsened indirectly through blood transfusion and other factors. These findings should be recognized when treating colorectal cancer with invasion to other organs.
