[Clinicopathologic study on venous invasion of colo-rectal cancer: a prospective study]

Metachronous liver metastasis developed less than in 5% of v0 and v1 groups, while it developed in 22% of v2 and v3 groups. In addition, it developed in 15% of EF(I) group, in 19% of EF group, in 10% of Intramural greater than Extramural group and in 16% of the Intramural less than or equal to Extramural group. Six-year survival rate of v0, v1, v2 and v3 groups in the cases of curative resection for advanced colo-rectal cancer were 97%, 85%, 57% and 51%, respectively. Also those of E, EF, EI(F), Intramural, Intramural greater than Extramural and Intramural less than or equal to Extramural groups were 83%, 65%, 55%, 86%, 80% and 55%, respectively. Non-hematogenous recurrence developed in 19.4% of v3 group, in 13.6% of EF(I) group and in 15% of Intramural less than or equal to Extramural group. Conclusions were as follows: (1) There was a close relationship between venous invasion and development of liver metastasis (or of non-hematogenous recurrence) and survival of patients. (2) It was proved that the diagnostic criteria of venous invasion established by the authors were good indices to predict survival of colo-rectal cancer patients.