Abstract
Proliferating cell nuclear antigen (PCNA), which is an auxiliary protein for DNA polymerase delta specific for the S-phase of the cell cycle, was employed for evaluating the degree of tumor cell proliferation. The expression of PCNA was studied immunohistochemically in 125 specimens from 66 laryngeal carcinomas, by using monoclonal anti-PCNA antibody (DAKO, PC10).
The PCNA labeling index (percentage of positive cells per 500 tumor cells) ranged from 19.0 to 68.4% (average; 41.0%). Speaman Rank Correlation demonstrated a significant relationship between the PCNA labeling index and mitotic index (R=0.654, p<0.01). Between biopsy specimen and surgical specimen, there was no difference in the PCNA labeling index. The PCNA labeling index increased with stage of the disease and T-classification. The labeling index with neck metastasis was highter than that without metastasis. There was no significant correlation between the labering index and tumor cell differentiation or tumor location. After radiotherapy, the labeling index decreased in patients with high pretreatment values, whereas it increased in patients with low pretreatment values. In this study, the PCNA labeling index did not indicate the possibility of tumor recurrence and metastasis during follow-up.
