A Rising PSA Does Not Predict Overall Survival After Radical Prostatectomy for Localized Prostate Cancer

Abstract & Commentary

Synopsis: At 10 years, patients with a PSA recurrence after radical prostatectomy for localized disease have an excellent overall survival equivalent to those without a detectable PSA.

Source: Jhaveri FM, et al. Urology 1999;54:884-890.

The objective of this study was to compare the overall survival in men with biochemical failure (bF) to those with no bF after radical prostatectomy for localized prostate cancer.

Radical prostatectomy was performed in 1132 consecutive patients between June 1986 and September 1998 and bF (prostate specific antigen [PSA] ³ 0.2 ng/mL) with a mean follow-up of 56 months (range, 1-125). A total of 99 patients were treated with androgen ablation, and/or radiation) was documented in 213 patients (19%), with a mean follow-up therapy at the time of bF. Kaplan-Meier estimates of bF, metastasis-free survival, and overall survival were generated and compared.

The 10-year overall survival rates for patients with bF (88%) vs. patients with no bF (93%) were similar (P = 0.94). The survival rates of patients with bF were not statistically different than those of patients without bF when compared by age older than 65 years, preoperative PSA greater than 10 ng/mL, biopsy or specimen Gleason score of 7 or greater, clinical stage T2b-3, presence of extracapsular extension, positive surgical margins, and seminal vesicle invasion. Patients who received second-line treatment also had a similar 10-year survival rate (86%, P = 0.97). For 213 patients with bF, the metastasis-free survival rate at 10 years was 74%. The overall survival rate for patients with distant metastasis (56%) was markedly lower than those without distant metastasis. Jhaveri and colleagues conclude that at 10 years, patients with a PSA recurrence after radical prostatectomy for localized disease have an excellent overall survival equivalent to those without a detectable PSA. Within this period, the clinical significance of a detectable PSA needs to be further evaluated.

Comment by Ralph R. Hall, MD, FACP

I have recently given a lot of thought to PSAs. I received a physical examination on an afternoon following some intense interval running. My PSA drawn that afternoon was 6 ng/mL. I was assured that exercise would not alter my PSA results. However, I asked for a repeat and for a percent-free PSA to be determined. The repeat PSA was 4.6 ng/mL and the percent-free PSA was 15%. Approximately one year earlier, my PSA had been 4 ng/mL, so I reasoned that my PSA velocity was less than 0.75 ng/mL per year and might not be so bad.

The percent-PSA of 15% seemed to convince everyone that I had prostate cancer. A look at a recent report on age-related PSA and percent-free PSA reduced my concern, however. In the report by Kalish and McKinlay involving 983 men (96% white), it was demonstrated that the percent-PSA does not change with age.1 The 50th and fifth percentiles of percent-PSA in their study were 25.3% and 13.2%, respectively. Thus, a PSA of 15% was not necessarily diagnostic of cancer. My biopsy was negative for prostate cancer.

As PSA determinations are refined and more data regarding age, race, and initial levels of free PSA are accumulated, we should develop better prognostic specificity and sensitivity for these tests. In the meantime, they are helpful guides, but a thorough rectal examination is still a useful test.

Reference

1. Kalish LA, McKinlay JB. Urology 1999;54:1022-1027.

Which one of the following statements is not true?

a. PSA velocity of less than 0.75 ng/mL is not likely to indicate the presence of prostate cancer.

b. The percent-free PSA does not change with age.

c. 50% of men have percent-free PSAs of less than 25.3%

d. The overall survival rate in patients with distance metastasis is the same as those with local extension of prostate cancer.