[A clinicopathological study on hematogenous recurrence of colo-rectal cancer--with special reference to prediction and prevention of the recurrence].

Hematogenous recurrence was investigated in 325 cases of colo-rectal cancer. Hematogenous recurrence was confirmed in 34 cases including 25 liver, 5 lung, 2 bone, one brain and one skin recurrence. Most of the cases (28 cases, 82.4%) revealed a single or multiple hematogenous recurrences without showing additional other types of recurrence. Histological examination of cancer lesions indicated that patients with the findings consisting of moderate and/or high grade of vein invasion (v2-3), subserosal and extramural vein invasion with node metastasis showed high recurrent rate. One and two year survival rate of the patients treated with MF-MF' adjuvant chemotherapy was greater those the patients with F-F' chemotherapy or those without chemotherapy. However, 3-, 4- and 5- year survival rate did not show significant difference among 3 therapeutic groups. The analysis of survival curves also indicated no significant difference among 3 therapeutic groups. These results may suggest that hematogenous recurrence is derived from pre- and/or intra-operative micrometastasis or transplantation of cancer cells, that patients with the above mentioned histological evidence must be clinically treated as a high risk group for recurrence and that MF-MF' adjuvant chemotherapy can be effective in lowering the recurrence rate during the first one or two years after operation.