Assessment of the biologic markers p53, Ki-67, and apoptotic index as predictive indicators of prostate carcinoma recurrence after surgery.

BACKGROUND

This study was designed to evaluate the potential of the molecular and cellular markers p53, Ki-67, and apoptotic index (AI) as adjuncts to the commonly available variables of tumor grade, clinical stage, and serum prostate specific antigen to predict prostate carcinoma recurrence after radical prostatectomy.

METHODS

Representative punch biopsy specimens of prostate carcinoma from whole mount paraffin blocks were evaluated from 47 men who underwent radical prostatectomy. Two groups were defined: those without evidence of prostate carcinoma recurrence after 5 years of follow-up (N = 30) and those with carcinoma recurrence (N = 17). Gleason grade, clustered p53 immunostaining, Ki-67 immunostaining, and AI were determined by standard techniques.

RESULTS

All variables tested were associated with disease recurrence by univariate analysis: AI (P = 0.005), clustered p53 immunostaining (P = 0.0070), and Ki-67 immunostaining (P = 0.0390). Using multivariate analyses that included each biomarker with routinely available features, only AI (P = 0.0234) and clustered p53 immunostaining (P = 0.0389) added independent prognostic information (Ki-67 immunostaining, P = 0.1285). In the final logistic regression model that included standard variables with AI and p53, only AI reached statistical significance (P = 0.0332).

CONCLUSIONS

The continued assessment of additional biomarkers for prostate carcinoma recurrence is important to identify better those patients who may be candidates for early adjuvant therapy and also to further our understanding of the neoplastic potential of a particular malignancy.