Accelerated tumor proliferation rates in locally recurrent prostate cancer after radical prostatectomy.

Abstract

We compared the growth rates of primary cancer and prostatic fossa recurrence after radical prostatectomy. Tumor proliferative rates were studied in 26 patients with biopsy proved prostatic fossa recurrences after radical prostatectomy. Proliferation was calculated in the prostatectomy specimens and in recurrent cancer using Ki-67 antibody to detect dividing cells. Mean and median labeling indexes for radical prostatectomy specimens were 2.96 and 2.51, respectively. Labeling indexes in locally recurrent tumors were significantly higher (mean 6.47, median 5.59, p < 0.001). The increase in labeling index between parent and recurrent tumors was unrelated to pathological staging at prostatectomy or interval from radical prostatectomy. Tumors that recur locally after radical prostatectomy appear to have a higher proliferative rate compared to parent tumors.