Assessment of proliferating cell nuclear antigen (PCNA) immunoreactivity in exocrine pancreatic carcinomas

Ten patient with exocrine pancreatic carcinomas were studied immunohistochemically, using a monoclonal antibody against PCNA. The percentage of tumor cells with positive staining was defined as PCNA Labelling Index (L.I.), and ranged from 13.8% to 92.8%. PCNA L.I. was found to correlate significantly with grading and more specifically with mitotic activity and degree of nuclear anaplasia. No correlation was found with granular differentiation or with vessel invasion, lymphatic vessel invasion, lymph node metastasis, perineural invasion or size of tumor. Our results indicate that mitotic activity and degree of nuclear anaplasia might be the most important parameters to take into consideration, when studying the role of PCNA in exocrine pancreatic carcinomas.