[Proliferating cell nuclear antigen/cyclin (PCNA/Cyclin) in thyroid carcinoma].

An immunohistochemical study of thyroid carcinoma using PC10, a monoclonal antibody against proliferating cell nuclear antigen (PCNA/Cyclin), was performed on paraffin sections. There was significant difference statistically in PCNA index between any two types of all four types of thyroid carcinoma (P < 0.01), with the index of 35.36 +/- 9.59 in papillary carcinoma, 184.60 +/- 7.08 in follicular carcinoma, 392.43 +/- 31.66 in medullary carcinoma, and 488.28 +/- 19.93 in undifferentiated carcinoma. The results indicate that PCNA/Cyclin detection is a reliable method to examine the fraction of proliferating cells of thyroid carcinoma on paraffin sections, and it could be used to determine the prognosis of thyroid carcinoma.