抄録
We analyzed the proliferative activity of cells in superficial type lesions of colorectal neoplasms by immunohistological staining of proliferating cell nuclear antigen (PCNA) and by comparing labeling indices (PCNA-LI) . In particular, we compared the proliferative activities of superficial elevated type lesions in two age groups. Old age (≥70 years) and pre-old age (<70 years) . Among 43 samples there were no significant differences in the PCNA-LI between mucosal carcinoma (m-carcinoma) and adenoma, or between neoplasms that fell into two size groups (diameters ≤ 0.5 cm and ≥ 0.6 cm) . Comparison of PCNA-LI between different age groups showed a lower value (26.3%) in the old age group than in the pre-old age group (31.6%), but this difference was not significant. Of the 27 superficial elevated neoplasms, when considering the entire layer of lesion, PCNA-LI was 23.3% in the old age group and 33.2% in the pre-old age group. However, when considering the surface layer of these lesions, values were 17.0% and 32.2% in the old age and pre-old age groups, respectively. In the deep layer, values were 29.7% and 34.2% in the old age and pre-old age groups, respectively. The PCNA-LI in the surface layer was statistically significantly different between the two age groups, suggesting that proliferative activity in colorectal superficial elevated type lesions varies, depending on the age of the patient.
