Abstract
Fifty-seven patients with advanced colorectal carcinoma who had undergone curative resection during the previous 20 years were clinico-pathologically studied. Among them, 25 cases showed hematogenous recurrence after surgery (Group A), and 32 cases remained disease free for at least 10 years after surgery (Group B). The histological grade of malignancy was investigated with regrad to histological subtype as follows: (1) histological change (changes in the histological grade of differentiation as tumor invasion); (2) por component (tumor with single cells like those of poorly differentiated adenocarcinoma at the invading margin); (3) mucinous component (tumor with mucinous component). The incidence of histological change in group A (64.0%) was significantly higher than that in group B (25.0%). The incidence of por component in group A (84.0%) was also significantly higher than that in group B (40.0%), whereas the incidence of mucinous component in group A (28.0%) was almost the same that in group B (34.4%). Furthermore, the incidence of lymph node metastasis in the cases with por component (64.7%) was significantly higher than that in the cases without por compoment. In conclusion, colorectal carcinoma with por component at the invading margin of the tumor was considered a high risk factor for hematogenous recurrence.