p53 alteration in regional lymph node metastases from prostate carcinoma: a marker for progression?

BACKGROUND Alterations of the p53 tumor suppressor gene are associated with advanced stage prostate carcinoma. The biologic significance of p53 nuclear accumulation in prostate cancer patients with regional lymph node metastases is uncertain. METHODS The authors investigated p53 alterations by immunohistochemistry in 220 lymph node positive patients who were treated with radical prostatectomy, bilateral pelvic lymphadenectomy, and androgen deprivation therapy between 1987–1992 at the Mayo Clinic. The mean follow-up was 6.3 years. Tumor volume of lymph node metastases was measured using the grid method. RESULTS p53 immunoreactivity was detected in 109 of 211 primary tumors (52%) and 83 of 144 matched regional lymph node metastases (58%); this expression was strongly concordant (correlation coefficient = 0.53; P = 0.0001). Overexpression of p53 protein in lymph node metastases was associated with distant metastasis free survival by univariate analysis (P = 0.03), but did not reach statistical significance by multivariate analysis (P = 0.07). Regional lymph node cancer volume was the single most important predictor of distant metastases after adjusting for Gleason score, DNA ploidy, and p53 expression. CONCLUSIONS The findings of the current study suggest that assessment of biologic changes (including p53 alterations in regional lymph node metastases) could be of value in the assessment of the biologic aggressiveness of prostate carcinoma, whereas p53 expression in the primary tumor does not appear to influence patient outcome. Cancer 1999;85:2455–9. © 1999 American Cancer Society.