Prognostic value of nucleolar organizer regions in endoscopically biopsied tissues of colorectal cancers.

We studied the proliferative activity in endoscopically biopsied tumors by means of argyrophil-protein nucleolar organizer region (AgNOR) scores. AgNOR scores of 109 colorectal cancers ranged from 2.48 to 6.72 (mean: 3.27 +/- 0.52). The 109 tumors were divided into two groups by the median value of AgNOR counts. There was no significant correlation between the AgNOR scores and the histologic type, invasion of bowel wall, lymph node metastases or peritoneal metastases. There was a significant association between the AgNOR scores and lymphatic invasion or liver metastases. Patients with higher AgNOR score tumors had significantly poorer prognoses than those with lower AgNOR score tumors. In Dukes' stage C, especially, the survival rate for patients with higher AgNOR score tumors was significantly lower than for those with lower AgNOR score tumors. Recurrence was found in 8.7% of the tumors with lower AgNOR scores and 19.4% of the tumors with higher scores. Aneuploid tumors had higher AgNOR scores than tumors with the diploid pattern. The results suggest that the AgNOR scores may possibly be a useful prognostic marker of colorectal cancer.