Immediate vs. delayed androgen deprivation for prostate cancer

Early versus deferred standard androgen suppression therapy for advanced hormone-sensitive prostate cancer

BACKGROUND

Standard androgen suppression therapy (AST) using surgical or medical castration is considered a mainstay of advanced hormone-sensitive prostate cancer treatment. AST can be initiated early when disease is asymptomatic or deferred when patients suffer symptoms of disseminated prostate cancer.

OBJECTIVES

To assess the effects of early versus deferred standard AST for advanced hormone-sensitive prostate cancer.

SEARCH METHODS

For this Cochrane Review update, we performed a comprehensive search of multiple databases (CENTRAL, MEDLINE, Embase, Web of Science; last searched November 2018) and two clinical trial registers, with no restrictions on the language of publication or publication status. We also searched bibliographies of included studies and conference proceedings (last searched January 2019).

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) with a direct comparison of early versus deferred standard AST. We excluded all other study designs. Participants included had advanced hormone-sensitive prostate cancer receiving surgical or medical castration.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data. The primary outcomes were time to death of any cause and serious adverse events. Secondary outcomes were time to disease progression, time to death from prostate cancer, adverse events and quality of life. We performed statistical analyses using a random-effects model and assessed the certainty of evidence according to GRADE. We performed subgroup analyses for advanced but non-metastatic disease (T2-4/N+ M0), metastatic disease (M1), and prostate-specific antigen (PSA) relapse.

MAIN RESULTS

We identified seven new RCTs since publication of the original review in 2002. In total, we included 10 RCTs.Primary outcomesEarly AST probably reduces the risk of death from any cause over time (hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.75 to 0.90; moderate-certainty evidence; 4767 participants). This corresponds to 57 fewer deaths (95% CI 80 fewer to 31 fewer) per 1000 participants at 5 years for the moderate risk group and 23 fewer deaths (95% CI 32 fewer to 13 fewer) per 1000 participants at 5 years in the low risk group. We downgraded for study limitations. Early versus deferred AST may have little or no effect on serious adverse events (risk ratio (RR) 1.05, 95% CI 0.95 to 1.16; low-certainty evidence; 10,575 participants) which corresponds to 6 more serious adverse events (6 fewer to 18 more) per 1000 participants. We downgraded the certainty of evidence for study limitations and selective reporting.Secondary outcomesEarly AST probably reduces the risk of death from prostate cancer over time (HR 0.69, 95% CI 0.57 to 0.84; moderate-certainty evidence). This corresponds to 62 fewer prostate cancer deaths per 1000 (95% CI 87 fewer to 31 fewer) at 5 years for the moderate risk group and 24 fewer death from prostate cancer (95% CI 34 fewer to 12 fewer) per 1000 men at 5 years in the low risk group. We downgraded the certainty of evidence for study limitations.Early AST may decrease the rate of skeletal events (RR 0.37, 95% CI 0.17 to 0.80; low-certainty evidence) corresponding to 23 fewer skeletal events per 1000 (95% CI 31 fewer to 7 fewer). We downgraded for study limitations and imprecision. It may also increase fatigue (RR 1.41, 95% CI 1.23 to 1.62; low-certainty evidence), corresponding to 31 more men with this complaint per 1000 (95% CI 18 more to 48 more). We downgraded for study limitations and imprecision. It may increase the risk of heart failure (RR 1.90, 95% CI 1.09 to 3.33; low-certainty evidence) corresponding to 27 more events per 1000 (95% CI 3 more to 69 more). We downgraded the certainty of evidence for study limitations and imprecision.Global quality of life is probably similar after two years as assessed with the EORTC QLQ-C30 (version 3.0) questionnaire (mean difference -1.56, 95% CI -4.50 to 1.38; moderate-certainty evidence) with higher scores reflecting better quality of life. We downgraded the certainty of evidence for study limitations.

AUTHORS' CONCLUSIONS

Early AST probably extends time to death of any cause and time to death from prostate cancer. It may slightly decrease the rate of skeletal events. Rates of serious adverse events and quality of life may be similar. It may increase fatigue and may increase the risk of heart failure. Better quality trials would be particularly important to better understand the outcomes related to possible treatment-related harm, for which we only found low-certainty evidence.

PSA doubling time predicts the outcome after active surveillance in screening-detected prostate cancer: results from the European randomized study of screening for prostate cancer, Sweden section

This study reports the outcome of active surveillance in men with PSA screening-detected prostate cancer (PC), and PSA doubling time (PSADT) was evaluated as a predictor of selecting patients to active treatment or surveillance. On December 31, 1994, 10,000 men were randomized to biennial PSA testing. Through to December 2004, a total of 660 men were diagnosed with PC, of whom 270 managed with initial surveillance. Of these 270 patients, 104 (39%) received active treatment during follow-up, 70 radical prostatectomy, 24 radiation and 10 endocrine treatment. Those who received active treatment during follow-up (mean 63 months) were significantly younger (62.6 vs. 65.5 years, p < 0.0001) and had a shorter PSADT (3.7 vs. 12 years, p < 0.0001). PSA relapse was observed in 9 of 70 patients who received RRP during a mean follow-up of 37 months. Seven of these nine PSA relapses were in the patients with preoperative PSADT < 2 years. None of the 37 operated patients with a PSADT > 4 years had a PSA relapse. In a Cox regression analysis adjusted for PSA, ratio-free PSA and amount of cancer in biopsy, only the preoperative PSADT was statistically significant predictor of PSA relapse in p = 0.031. The optimal candidate for surveillance is a man with early, low-grade, low-stage PC and a PSADT > 4 years. In younger men with a PSADT of less than 4 years, surveillance does not seem to be a justified alternative, and patient should be informed about the risk with such an approach.

Prognostic value of circulating prostate cells in patients with a rising PSA after radical prostatectomy

BACKGROUND

To predict poor outcome in patients with a biochemical recurrence (rising PSA) after radical prostatectomy (RP), urologists rely primarily on Gleason score, PSA doubling time, and time from surgery to biochemical (i.e., PSA) recurrence. In the present study, we assess the value of RT-PCR detection circulating prostate cells in blood of patients with a rising PSA.

METHODS

RNA from blood samples was obtained from 55 patients with a rising PSA and from 45 patients without evidence of biochemical failure (PSA < 0.1 ng/ml). Both groups were matched for age, Gleason score, pT stage, and interval between radical prostatectomy and PCR testing.

RESULTS

PSA positive cells were detected in 1/45 (2%) patients without a PSA recurrence and 19/55 (34%) patients with a PSA recurrence. In the rising PSA group, mean PSA doubling time was significantly shorter in patients with positive RT-PCR (5 months) than in patients with negative RT-PCR (16 months; P = 0.001). An earlier onset of recurrence was also detected in patients with a positive RT-PCR (31 months for positive RT-PCR vs. 50 months for negative RT-PCR) but this result did not achieve statistical significance (P = 0.102). Salvage radiation therapy was administered in 15 patients. Three of the five patients with a positive RT-PCR progressed during radiotherapy whereas 7 of the 10 patients with a negative RT-PCR obtained a complete response and none have progressed.

CONCLUSIONS

These preliminary results suggest that RT-PCR detection of prostate cells in blood of patients after RP correlates with rapidly progressing biochemical failure after RP.

Regulation of the expression of protein kinase C isoenzymes in rat ventral prostate: effects of age, castration and flutamide treatment

Protein kinase C (PKC) isoenzymes are involved in cell function, growth, apoptosis and neoplastic transformation in the prostate gland. We detected by means of Western blot the expression of the classical alpha and beta1, the novel epsilon and the atypical zeta isoforms of PKC in ventral prostates from rats with different extents of plasma testosterone levels and/or androgen imprinting on the gland. The expression of the four isoforms decreased in 5-day castrated rats showing apoptotical regression of the gland and a drastic reduction of circulating testosterone. However, the expression of PKC isoenzymes (alpha, beta1, epsilon ) increased in prostates from pubertal (35-days old) rats that are characterized by relatively low but extremely bioactive testosterone plasma levels. Treatment of adult rats for 14 days with flutamide (daily s.c. injection of 15 mg/Kg B.W.) resulted in increased expression of the four isoenzymes; it occurred in the presence of increased (normal rats) or drastically reduced (rats castrated after 9 days of flutamide administration) levels of plasma testosterone conceivably through a direct effect of this nonsteroidal antiandrogen on prostate cells. Measurements of PKC(alpha) activity were in agreement with the observations on protein expression and showed that flutamide (that is extensively used in the treatment of advanced prostate cancer) elicits some impairment in the mechanisms of translocation of this isoform from the cytosol to the membrane. Thus, in addition to the possibility of direct effects of flutamide upon the rat prostate, we present evidence that the levels of circulating androgens and/or their bioactivity in the gland regulate the expression of various important PKC isoforms.