[Growth fractions of bladder cancer determined by proliferating cell nuclear antigen immunostaining]

Immunohistochemical staining of proliferating cell nuclear antigen (PCNA) can be performed on conventionally fixed and processed tissue. We applied anti-PCNA monoclonal antibodies to transurethrally resected bladder cancer specimens. The labelling index (LI) of PCNA increased with tumor grade and that of the invasive tumor group was higher than that of the non-invasive tumor group. Especially in large tumors, there was intratumoral variation of labelled cell distribution, which may represent tumor heterogeneity. These findings suggest that PCNA might be a useful marker for bladder cancer proliferation.