Unrecognized kinetics of serum testosterone: impact on short-term androgen deprivation therapy for prostate cancer

Survival Outcomes of Concurrent Treatment with Docetaxel and Androgen Deprivation Therapy in Metastatic Castration-Resistant Prostate Cancer

PURPOSE

Docetaxel-based chemotherapy (DTX) improves overall survival (OS) of men with metastatic castration-resistant prostate cancer (mCRPC). Considering the potential existence of androgen receptors that remain active at this stage, we aimed to assess the impact of the combined use of androgen deprivation therapy (ADT) with DTX for mCRPC.

MATERIALS AND METHODS

We performed a single-institutional retrospective analysis of patients with mCRPC who received either DTX alone (DTX group, n=21) or concurrent DTX and ADT (DTX+ADT group, n=26) between August 2006 and February 2014. All patients received DTX doses of 75 mg/m² every three weeks for at least three cycles. In the DTX+ADT group, all patients used luteinizing hormone releasing hormone agonist continuously as a concurrent ADT.

RESULTS

The median follow-up period was 24.0 months (interquartile range 12.0-37.0) for the entire cohort. The median radiographic progression-free survival (rPFS) was 9.0 months and 6.0 months in the DTX+ADT and DTX groups, respectively (log-rank p=0.036). On multivariable Cox regression analysis, concurrent administration of ADT was the only significant predictor of rPFS [hazard ratio (HR)=0.525, 95% confidence intervals (CI) 0.284-0.970, p=0.040]. The median OS was 42.0 and 38.0 months in the DTX+ADT and DTX groups, respectively (log-rank p=0.796). On multivariable analysis, hemoglobin level at the time of DTX initiation was associated with OS (HR=0.532, 95% CI 0.381-0.744, p<0.001).

CONCLUSION

In chemotherapy-naive patients with mCRPC, the combined use of ADT with DTX improved rPFS. Our result suggests that the concurrent administration of ADT and DTX is superior to DTX alone.

Exponential rise in prostate-specific antigen (PSA) during anti-androgen withdrawal predicts PSA flare after docetaxel chemotherapy in patients with castration-resistant prostate cancer

PURPOSE

To investigate the relationship between rising patterns of prostate-specific antigen (PSA) before chemotherapy and PSA flare during the early phase of chemotherapy in patients with castration-resistant prostate cancer (CRPC).

MATERIALS AND METHODS

This study included 55 patients with CRPC who received chemotherapy and in whom pre-treatment or post-treatment PSA levels could be serially obtained. The baseline parameters included age, performance, Gleason score, PSA level, and disease extent. PSA doubling time was calculated using the different intervals: the conventional interval from the second hormone manipulation following the nadir until anti-androgen withdrawal (PSADT1), the interval from the initial rise after anti-androgen withdrawal to the start of chemotherapy (PSADT2), and the interval from the nadir until the start of chemotherapy (PSADT3). The PSA growth patterns were analyzed using the ratio of PSADT2 to PSADT1.

RESULTS

There were two growth patterns of PSA doubling time: 22 patients (40.0%) had a steady pattern with a more prolonged PSADT2 than PSADT1, while 33 (60.0%) had an accelerating pattern with a shorter PSADT2 than PSADT1. During three cycles of chemotherapy, PSA flare occurred in 11 patients (20.0%); of these patients, 3 were among 33 (9.1%) patients with an accelerating PSA growth pattern and 8 were among 22 patients (36.4%) with a steady PSA growth pattern (p=0.019). Multivariate analysis showed that only PSA growth pattern was an independent predictor of PSA flare (p=0.034).

CONCLUSION

An exponential rise in PSA during anti-androgen withdrawal is a significant predictor for PSA flare during chemotherapy in CRPC patients.

Pharmacological interventions for those who have sexually offended or are at risk of offending

BACKGROUND

Sexual offending is a serious social problem, a public health issue, and a major challenge for social policy. Victim surveys indicate high incidence and prevalence levels and it is accepted that there is a high proportion of hidden sexual victimisation. Surveys report high levels of psychiatric morbidity in survivors of sexual offences.Biological treatments of sex offenders include antilibidinal medication, comprising hormonal drugs that have a testosterone-suppressing effect, and non-hormonal drugs that affect libido through other mechanisms. The three main classes of testosterone-suppressing drugs in current use are progestogens, antiandrogens, and gonadotropin-releasing hormone (GnRH) analogues. Medications that affect libido through other means include antipsychotics and serotonergic antidepressants (SSRIs).

OBJECTIVES

To evaluate the effects of pharmacological interventions on target sexual behaviour for people who have been convicted or are at risk of sexual offending.

SEARCH METHODS

We searched CENTRAL (2014, Issue 7), Ovid MEDLINE, EMBASE, and 15 other databases in July 2014. We also searched two trials registers and requested details of unidentified, unpublished, or ongoing studies from investigators and other experts.

SELECTION CRITERIA

Prospective controlled trials of antilibidinal medications taken by individuals for the purpose of preventing sexual offences, where the comparator group received a placebo, no treatment, or 'standard care', including psychological treatment.

DATA COLLECTION AND ANALYSIS

Pairs of authors, working independently, selected studies, extracted data, and assessed the risk of bias of included studies. We contacted study authors for additional information, including details of methods and outcome data.

MAIN RESULTS

We included seven studies with a total of 138 participants, with data available for 123. Sample sizes ranged from 9 to 37. Judgements for categories of risk of bias varied: concerns were greatest regarding allocation concealment, blinding of outcome assessors, and incomplete outcome data (dropout rates in the five community-based studies ranged from 3% to 54% and results were usually analysed on a per protocol basis).Participant characteristics in the seven studies were heterogeneous, but the vast majority had convictions for sexual offences, ranging from exhibitionism to rape and child molestation.Six studies examined the effectiveness of three testosterone-suppressing drugs: cyproterone acetate (CPA), ethinyl oestradiol (EO), and medroxyprogesterone acetate (MPA); a seventh evaluated two antipsychotics (benperidol and chlorpromazine). Five studies were placebo-controlled; in two, MPA was administered as an adjunctive treatment to a psychological therapy (assertiveness training or imaginal desensitisation). Meta-analysis was not possible due to heterogeneity of interventions, comparators, study designs, and other issues. The quality of the evidence overall was poor. In addition to methodological issues, much evidence was indirect.

PRIMARY OUTCOME

recividism. Two studies reported recidivism rates formally. One trial of intramuscular MPA plus imaginal desensitisation (ID) found no reports of recividism at two-year follow-up for the intervention group (n = 10 versus one relapse within the group treated by ID alone). A three-armed trial of oral MPA, alone or in combination with psychological treatment, reported a 20% rate of recidivism amongst those in the combined treatment arm (n = 15) and 50% of those in the psychological treatment only group (n = 12). Notably, all those in the 'oral MPA only' arm of this study (n = 5) dropped out immediately, despite treatment being court mandated.Two studies did not report recidivism rates as they both took place in one secure psychiatric facility from which no participant was discharged during the study, whilst another three studies did not appear directly to measure recividism but rather abnormal sexual activity alone.

SECONDARY OUTCOMES

The included studies report a variety of secondary outcomes. Results suggest that the frequency of self reported deviant sexual fantasies may be reduced by testosterone-suppressing drugs, but not the deviancy itself (three studies). Where measured, hormonal levels, particularly levels of testosterone, tended to correlate with measures of sexual activity and with anxiety (two studies). One study measured anxiety formally; one study measured anger or aggression. Adverse events: Six studies provided information on adverse events. No study tested the effects of testosterone-suppressing drugs beyond six to eight months and the cross-over design of some studies may obscure matters (given the 'rebound effect' of some hormonal treatments). Considerable weight gain was reported in two trials of oral MPA and CPA. Side effects of intramuscular MPA led to discontinuation in some participants after three to five injections (the nature of these side effects was not described). Notable increases in depression and excess salivation were reported in one trial of oral MPA. The most severe side effects (extra-pyramidal movement disorders and drowsiness) were reported in a trial of antipsychotic medication for the 12 participants in the study. No deaths or suicide attempts were reported in any study. The latter is important given the association between antilibidinal hormonal medication and mood changes.

AUTHORS' CONCLUSIONS

We found only seven small trials (all published more than 20 years ago) that examined the effects of a limited number of drugs. Investigators reported issues around acceptance and adherence to treatment. We found no studies of the newer drugs currently in use, particularly SSRIs or GnRH analogues. Although there were some encouraging findings in this review, their limitations do not allow firm conclusions to be drawn regarding pharmacological intervention as an effective intervention for reducing sexual offending.The tolerability, even of the testosterone-suppressing drugs, was uncertain given that all studies were small (and therefore underpowered to assess adverse effects) and of limited duration, which is not consistent with current routine clinical practice. Further research is required before it is demonstrated that their administration reduces sexual recidivism and that tolerability is maintained.It is a concern that, despite treatment being mandated in many jurisdictions, evidence for the effectiveness of pharmacological interventions is so sparse and that no RCTs appear to have been published in two decades. New studies are therefore needed and should include trials with larger sample sizes, of longer duration, evaluating newer medications, and with results stratified according to category of sexual offenders. It is important that data are collected on the characteristics of those who refuse and those who drop out, as well as those who complete treatment.