Prognostic value of proliferating cell nuclear antigen immunostaining in pediatric rhabdomyosarcomas.

Abstract

The levels of proliferating cell nuclear antigen (PCNA) are almost negligible in long-term quiescent cells and increase dramatically during the cell cycle. Recently, the monoclonal antibodies to PCNA have been used to demonstrate the proliferative component of paraffin-embedded tumor tissues. It has been shown to be available as a simple histological marker of proliferative activity and the PCNA labeling index has been correlated with the prognosis of several malignant neoplasms. Formalin fixed, paraffin embedded tissue specimens of 29 primary pediatric rhabdomyosarcomas were immunostained by using an anti-PCNA monoclonal antibody (DAKO PCNA PC10). The relationship between the PCNA index and prognosis, clinicopathological features and survival were assessed retrospectively. The mean PCNA index for the whole series was 54%. There was no correlation between PCNA index and any of the clinicopathological characteristics. However, patients having tumors with a high (> 54%) PCNA index demonstrated significantly lower survival rates than tumors with a low (< 54%) PCNA index (P = 0.01). Moreover, there were significantly more patients with relapse or progressive disease in the high PCNA index group (P = 0.005). The PCNA labeling index can be a useful prognostic factor and a good indicator of recurrence and/or survival in patients with rhabdomyosarcoma.