Does testosterone replacement therapy increase the risk of conversion to treatment in patients with prostate cancer on active surveillance?

PURPOSE

We aimed to evaluate the impact of testosterone replacement therapy (TRT) in patients with localized prostate cancer (CaP) who elected active surveillance (AS).

METHODS

A retrospective review of our CaP database was performed. Patients who received TRT while on AS were identified and were matched to a cohort of patient on AS while not on TRT (1:3) using propensity score matching. Treatment-free survival (TFS) was computed using Kaplan Meier method. Multivariable Cox regression model was used to evaluate variables associated with treatment.

RESULTS

Twenty-four patients in the TRT group were matched to 72 patients without TRT. Median follow-up was 5.82 years (IQR 3.27-9.30). There was no significant difference in conversion to treatment (24% vs. 21%, P = 1.00) There was no significant difference in TFS (log rank P = 0.87). Prostate specific antigen (PSA) density was the only variable associated TFS (HR 1.08, 95%CI 1.03-1.13, P = 0.001).

CONCLUSION

TRT was not associated with conversion to treatment in this matched analysis among patients with localized prostate cancer on AS.

Adult- and late-onset male hypogonadism: the clinical practice guidelines of the Italian Society of Andrology and Sexual Medicine (SIAMS) and the Italian Society of Endocrinology (SIE)

PURPOSE

To provide the evidence-based recommendations on the role of testosterone (T) on age-related symptoms and signs remains.

METHODS

The Italian Society of Andrology and Sexual Medicine (SIAMS) and the and the Italian Society of Endocrinology (SIE) commissioned an expert task force to provide an updated guideline on adult-onset male hypogonadism. Derived recommendations were based on Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

RESULTS

Clinical diagnosis of adult-onset hypogonadism should be based on a combination of clinical and biochemical parameters. Testosterone replacement therapy (TRT) should be offered to all symptomatic subjects with hypogonadism after the exclusion of possible contraindications. T gels and the long-acting injectable T are currently available preparations showing the best efficacy/safety profile. TRT can improve all aspects of sexual function, although its effect is limited in more complicated patients. Body composition (reducing fat mass and increasing lean mass) is improved after TRT, either in subjects with or without metabolic syndrome or type 2 diabetes. Conversely, the role of TRT in improving glycometabolic control is more conflicting. TRT can result in increasing bone mineral density, particularly at lumbar site, but no information on fracture risk is available. Limited data support the use of TRT for improving other outcomes, including mood frailty and mobility.

CONCLUSIONS

TRT can improve sexual function and body composition particularly in less complicated adult and in aging subjects with hypogonadism. When hypogonadism is adequately diagnosed, T appropriately prescribed and subjects correctly followed up, no short-term increased risk of adverse events is observed. Longer and larger studies are advisable to better clarify TRT long-term efficacy/safety profile.

Reverse intermittent androgen deprivation therapy: Prostate cancer and hypopituitarism

Testosterone replacement in the context of untreated prostate cancer is a controversial topic, where the symptomatic benefits of testosterone therapy contrast with the risk of disease progression. We report the case of a 76-year-old gentleman, under watchful waiting for known prostate cancer, who underwent a transsphenoidal resection of a pituitary macroadenoma. The adenoma and subsequent surgical treatment resulted in secondary testosterone deficiency, effectively ‘self-commencing’ endogenous androgen deprivation therapy. After discussion with the endocrine team, careful intermittent testosterone supplementation was undertaken to address his symptoms, with the patient undergoing prostate-specific antigen surveillance. This was felt to be similar to intermittent androgen deprivation therapy in reverse. Here, we review current evidence regarding testosterone therapy in the context of prostate cancer.

Level of Evidence: 5

Testosterone Replacement Therapy in Men with Untreated or Treated Prostate Cancer: Do We Have Enough Evidences?

PURPOSE

To investigate the oncologic safety of testosterone replacement therapy (TRT) in men with untreated or treated prostate cancer.

MATERIALS AND METHODS

We systematically searched PubMed, Embase, and Cochrane library database from January 1941 to March 2019.

RESULTS

In total, 36 articles met the eligibility criteria for this systematic review. They included a total of 2,459 TRT-treated patients, with a median of 20 patients per study (range: 1-1,142). Except for four studies, all were single-armed studies with poor quality scores (median MINOR, 9 of 24). Of the 36 studies, prostate cancer was managed through active surveillance (AS), in 5 studies; radical prostatectomy, in 11 studies; radiation therapy, in 5 studies; multiple intervention modalities, in 5 studies; and systemic therapy, in 9 studies. In comparison with TRT-treated and untreated patients, the pooled risk ratio (RR) was not significantly higher than one in comparisons of risk for disease progression (pooled RR, 0.83; 95% confidence interval, 0.57-1.21). The results of systematic review implied that TRT might be harmful in men with advanced disease (progression rate: 38.5%-100.0%), who undergo AS (15.4%-57.1%), and who successfully treated but having high-risk disease (0.0%-50.0%).

CONCLUSIONS

Compared to TRT-untreated patients, TRT-treated patients may not have increased risks for disease progression in prostate cancer. However, the quality of currently available evidence is extremely poor. TRT may be harmful in men with advanced disease burden, in those with untreated prostate cancer undergoing AS, and in those with successfully treated prostate cancer but having high-risk disease.

Late-onset hypogonadism: Prostate safety

BACKGROUND

There have always been concerns regarding testosterone replacement therapy and prostate safety because of the central role of testosterone in prostate tissue. Even though there is a body of evidence supporting that the benefits of testosterone replacement therapy outbalance the risks of prostate disease, this matter is still debatable and represents a common concern among testosterone prescribers.

OBJECTIVES

The aim of this article was to review the influence of testosterone on prostate pathophysiology and discuss the potential impact of testosterone replacement therapy on the most common prostate pathologies, including benign prostatic hyperplasia and prostate cancer.

MATERIALS AND METHODS

We have performed an extensive PubMed review of the literature examining the effects of testosterone replacement therapy on the prostate and its most common affections, especially in terms of safety.

RESULTS

Testosterone replacement therapy has been shown to improve components of metabolic syndrome and decrease prostate inflammation, which is related to the worsening of lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia. Studies evaluating the link between testosterone replacement therapy and benign prostatic hyperplasia/LUTS have mostly demonstrated no change in symptom scores and even some benefits. There are a significant number of studies demonstrating the safety of testosterone replacement therapy in individuals with late-onset hypogonadism and a history of prostate cancer. The most recently published guidelines have already acknowledged this fact and do not recommend against T treatment in this population, particularly in non-high-risk disease.

CONCLUSION

Testosterone replacement therapy could be considered for most men with late-onset hypogonadism regardless of their history of prostate disease. However, a discussion about the risks and benefits of testosterone replacement therapy is always advised, especially in men with prostate cancer. Appropriate monitoring is mandatory.

Testosterone, testosterone therapy and prostate cancer

With prostate cancer not observed in eunuchs and total androgen suppression by castration an effective first-line treatment for advanced prostate cancer, the dramatic regression seen in tumour symptoms after castration, lead to the theory that high levels of circulating androgens were a risk factor for prostate cancer. This theory however, ignored the effects testosterone variations within a physiologic range could have on early tumour events and since the early 2000s, clinical evidence discounting testosterone as a linear mechanistic cause of prostate cancer growth mounted, with alternative mechanistic hypotheses such as the saturation model being proposed. Together with a growing understanding of the negative health effects and decreased quality of life in men with testosterone deficiency or hypogonadism, a paradigm shift away from testosterone as a prostate cancer inducer occurred allowing clinicians to use testosterone therapy as potential treatment for men with difficult and symptomatic hypogonadism that had been previously treated for prostate cancer. In this review we contextualise the idea of testosterone as a risk factor for prostate cancer inducement and compile the most current literature with regards to the influence of testosterone and testosterone therapy in prostate cancer.

Safety of testosterone therapy in men with prostate cancer

Introduction: The use of testosterone therapy (TTh) in men with prostate cancer (PCa) is relatively new, and controversial, due to the longstanding maxim that TTh is contraindicated in men with PCa. Scientific advances have prompted a reevaluation of the potential role for TTh in men with PCa, particularly as TTh has been shown to provide important symptomatic and general health benefits to men with testosterone deficiency (TD), including many men with PCa who may expect to live 30-50 years after diagnosis. Areas covered: This review outlines the historical underpinnings of the historical belief that TTh 'fuels' PCa and the experimental and clinical studies that have radically altered this view, including description of the saturation model. The authors review studies of TTh in men with PCa following radical prostatectomy and radiation therapy, in men on active surveillance, and in men with advanced or metastatic PCa. Expert opinion: TTh provides important symptomatic and overall health benefits for men with PCa who have TD. Although more safety studies are needed, TTh is a reasonable therapeutic option for men with low-risk PCa after surgery or radiation. Data in men on active surveillance are limited, but initial reports are reassuring.

Shifting the Paradigm of Testosterone Replacement Therapy in Prostate Cancer

Historically, testosterone and prostate cancer have been demonstrated to have a positive association leading providers to forgo testosterone replacement therapy (TRT) in men with concurrent histories of hypogonadism and prostate cancer. This paradigm has been gradually shifting with our evolving understanding of the relationship between testosterone and prostate cancer and the gaining popularity of the saturation model. Newer data suggests improved quality of life for men with hypogonadism after TRT leading to a more tempered view of the effects of this treatment and its risk in prostate cancer. As more reports emerge of TRT in men who have either undergone definitive treatment for prostate cancer or are on active surveillance, some providers see a role for TRT in these patients despite non-consensus in clinical guidelines. It is critical that we examine evidence currently available, while we await more rigorous data to emerge.

Testosterone Replacement in a Man with Intermediate-risk Prostate Cancer

In brief, a hypogonadal man with successfully treated localized prostate cancer deserves testosterone therapy (TTh) regardless of grade. The evidence is not conclusive but compelling. The story is different for those with intermediate-risk disease who, for a variety of reasons, need TTh but cannot or elect not to have treatment of their primary malignancy, but still desire androgen supplementation.

Effects of Testosterone on Benign and Malignant Conditions of the Prostate

PURPOSE OF THE REVIEW

This review summarizes the current literature regarding the effects of testosterone therapy (TTh) on common disorders of the prostate.

RECENT FINDINGS

Testosterone therapy has gained credibility over the last several decades as a potentially safe co-treatment modality for men with benign and malignant prostatic conditions. Our understanding of the effects of testosterone on the prostate continues to evolve with ongoing clinical and basic science research. Findings of these studies have reinvigorated the debate over the effects of testosterone on benign and malignant disorders of the prostate, including BPH, chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and prostate cancer.

SUMMARY

Despite the burgeoning body of data claiming the safety and efficacy of TTh in common prostatic conditions (including BPH, CP/CPPS, and prostate cancer), diligent monitoring, appropriate patient selection, and informed consent are critical until more definitive studies are performed.

Testosterone therapy and prostate cancer

The use of exogenous testosterone to treat hypogonadism in the men with a history of prostate cancer (CaP) remains controversial due to fears of cancer recurrence or progression. Due to the detrimental impact of hypogonadism on patient quality of life, recent work has examined the safety of testosterone therapy (TTh) in men with a history of CaP. In this review, we evaluate the literature with regards to the safety of TTh in men with a history of CaP. TTh results in improvements in quality of life with little evidence of biochemical recurrence or progression in men with a history of CaP, or de novo cancer in unaffected men. An insufficient amount of evidence is currently available to truly demonstrate the safe use of TTh in men with low risk CaP. In men with high-risk cancer, more limited data suggest that TTh may be safe, but these findings remain inconclusive. Despite the historic avoidance of TTh in men with a history of CaP, the existing body of evidence largely supports the safe and effective use of testosterone in these men, although additional study is needed before unequivocal safety can be demonstrated.

Testosterone Therapy Among Prostate Cancer Survivors

INTRODUCTION

The use of testosterone in men with a history of prostate cancer remains controversial in light of established findings linking androgens to prostate cancer growth. However, hypogonadism significantly affects quality of life and has negative sequelae, and the risks and benefits of testosterone therapy might be worthwhile to consider in all men, even those with a history of high-risk prostate cancer.

AIM

To discuss the effects of testosterone on the prostate and the use of testosterone therapy in hypogonadal men with a history of prostate cancer.

METHODS

Review of the literature examining the effects of testosterone on the prostate and the efficacy and safety of exogenous testosterone in men with a history of prostate cancer.

MAIN OUTCOME MEASURES

Summary of effects of exogenous and endogenous testosterone on prostate tissue in vitro and in vivo, with a focus on effects in men with a history of prostate cancer.

RESULTS

Testosterone therapy ameliorates the symptoms of hypogonadism, decreases the risk for its negative sequelae, and can significantly improve quality of life. Recent studies do not support an increased risk for de novo prostate cancer, progression of the disease, or biochemical recurrence in hypogonadal men with a history of non-high-risk prostate cancer treated with testosterone therapy. Evidence supporting the use of testosterone in the setting of high-risk prostate cancer is less clear.

CONCLUSION

Despite the historical reluctance toward the use of testosterone therapy in men with a history of prostate cancer, modern evidence suggests that testosterone replacement is a safe and effective treatment option for hypogonadal men with non-high-risk prostate cancer. Additional work to definitively demonstrate the efficacy and safety of testosterone therapy in men with prostate cancer is needed, and persistent vigilance and surveillance of treated men remains necessary.

A survey of Canadian urologists' opinions and prescribing patterns of testosterone replacement therapy in men on active surveillance for low-risk prostate cancer

INTRODUCTION

Attitudes regarding the safety of testosterone replacement therapy (TRT) in hypogonadal men with prostate cancer (PCa) have changed over the past few years with the emergence of case studies suggesting a low risk of cancer progression and a better understanding of the interaction of different levels of androgen with prostate cellular metabolism. This new view has the potential to change clinical practice.

METHODS

Active members of the Canadian Urological Association were surveyed about their opinions on the safety of TRT in men with low-risk PCa, as well as their current prescribing habits.

RESULTS

Of 57 responding urologists, 86% actively prescribe TRT in men with testosterone deficiency syndrome (TDS), 93% are involved in the treatment of men with PCa, and 95% offer active surveillance as a management option for low-grade/low-stage disease. Furthermore, 65% stated that they would offer TRT to men with TDS who were on active surveillance for PCa and 63% believed that TRT did not increase the risk of progression of PCa in these men. In terms of treatment methods, 96% believed TRT was safe for men who have undergone radical prostatectomy, while a smaller number felt it was safe for patients who have undergone brachytherapy (86%) or external beam radiation (84%). Despite these figures, only 35% of the surveyed physicians had ever offered TRT for men on active surveillance and only 42% actually had men in their practice who were taking testosterone while on active surveillance.

CONCLUSIONS

The discrepancy between urologists' beliefs about the safety of TRT and their clinical practice patterns may be due to multiple factors, such as hesitation in recommending treatment in real-life practice, low numbers of eligible patients, absence of screening for testosterone deficiency in patients on active surveillance, and patient preference or fears. Furthermore, the difference in perceived safety in men treated by radical prostatectomy vs. radiation therapy suggests that some urologists are concerned that the radiated gland remaining in-situ may be "reactivated" by TRT. The results from this survey will be used as the basis of developing a national Canadian registry of men with low-grade/stage PCa who are receiving TRT while on active surveillance.

Testosterone Therapy in Men With Prostate Cancer

CONTEXT

The use of testosterone therapy in men with prostate cancer was previously contraindicated, although recent data challenge this axiom. Over the past 2 decades, there has been a dramatic paradigm shift in beliefs, attitude, and treatment of testosterone deficiency in men with prostate cancer.

OBJECTIVE

To summarize and analyze current literature regarding the effect of testosterone replacement in men with prostate cancer.

EVIDENCE ACQUISITION

We conducted a Medline search to identify all publications related to testosterone therapy in both treated and untreated prostate cancer.

EVIDENCE SYNTHESIS

The historical notion that increasing testosterone was responsible for prostate cancer growth was based on elegant yet limited studies from the 1940s and anecdotal case reports. Current evidence reveals that high endogenous androgen levels do not increase the risk of a prostate cancer diagnosis. Similarly, testosterone therapy in men with testosterone deficiency does not appear to increase prostate cancer risk or the likelihood of a more aggressive disease at prostate cancer diagnosis. Androgen receptor saturation (the saturation model) appears to account for this phenomenon. Men who received testosterone therapy after treatment for localized prostate cancer do not appear to suffer higher rates of recurrence or worse outcomes; although studies to date are limited. Early reports of men on active surveillance/watchful waiting treated with testosterone have not identified adverse progression events.

CONCLUSIONS

An improved understanding of the negative effects of testosterone deficiency on health and health-related quality of life-and the ability of testosterone therapy to mitigate these effects-has triggered a re-evaluation of the role testosterone plays in prostate cancer. An important paradigm shift has occurred within the field, in which testosterone therapy may now be regarded as a viable option for selected men with prostate cancer suffering from testosterone deficiency.

PATIENT SUMMARY

In this article, we review and summarize the existing literature surrounding the use of testosterone therapy in men with prostate cancer. Historically, testosterone was contraindicated in men with a history of prostate cancer. We show that this contraindication is unfounded and, with careful monitoring, its use is safe in that regard.

Testosterone deficiency in the aging male

Treatment for hypogonadism is on the rise, particularly in the aging population. Yet treatment in this population represents a unique challenge to clinicians. The physiology of normal aging is complex and often shares the same, often vague, symptoms of hypogonadism. In older men, a highly prevalent burden of comorbid medical conditions and polypharmacy complicates the differentiation of signs and symptoms of hypogonadism from those of normal aging, yet this differentiation is essential to the diagnosis of hypogonadism. Even in older patients with unequivocally symptomatic hypogonadism, the clinician must navigate the potential benefits and risks of treatment that are not clearly defined in older men. More recently, a greater awareness of the potential risks associated with treatment in older men, particularly in regard to cardiovascular risk and mortality, have been appreciated with recent changes in the US Food and Drug Administration recommendations for use of testosterone in aging men. The aim of this review is to provide a framework for the clinician evaluating testosterone deficiency in older men in order to identify correctly and treat clinically significant hypogonadism in this unique population while minimizing treatment-associated harm.

Recurrence of prostate cancer in patients receiving testosterone supplementation for hypogonadism

PURPOSE

The relationship between recurrent prostate cancer risk and testosterone replacement therapy (TRT) for hypogonadal men is explored.

SUMMARY

The medical literature was searched to identify articles evaluating the use of TRT in symptomatic hypogonadal men with a history of prostate cancer. Eight English-language articles investigating TRT use in hypogonadal men with a history of prostate cancer were analyzed. For evaluative purposes, the normal ranges used for prostate-specific antigen (PSA) and total testosterone levels were less than 4.0 ng/mL and 300-1000 ng/dL, respectively. Most trials were small and involved patients with localized prostate cancer treated with radical prostatectomy or radiotherapy, though patients with metastatic disease or a Gleason score of ≥8 were included in a few studies. TRT was administered in a variety of dosages and dosage forms for up to nine years to manage hypogonadal symptoms. Testosterone concentrations increased, as expected, after TRT, but serum PSA levels remained below 0.1 ng/mL in the majority of patients. PSA levels were found to increase in select patients with high-risk and metastatic disease, but these elevations were not accompanied by disease progression. These studies have suggested a potential benefit for TRT use in select symptomatic hypogonadal men with a history of prostate cancer. Data were limited, however, by the retrospective nature of most studies, the lack of control groups, small sample sizes, and short follow-up periods.

CONCLUSION

There is insufficient evidence to withhold TRT in certain populations of men with a history of prostate cancer.

Testosterone therapy in men with prostate cancer: literature review, clinical experience, and recommendations

For several decades any diagnosis of prostate cancer (PCa) has been considered an absolute contraindication to the use of testosterone (T) therapy in men. Yet this prohibition against T therapy has undergone recent re-examination with refinement of our understanding of the biology of androgens and PCa, and increased appreciation of the benefits of T therapy. A reassuringly low rate of negative outcomes has been reported with T therapy after radical prostatectomy (RP), radiation treatments, and in men on active surveillance. Although the number of these published reports are few and the total number of treated men is low, these experiences do provide a basis for consideration of T therapy in selected men with PCa. For clinicians considering offering this treatment, we recommend first selecting patients with low grade cancers and undetectable prostate-specific antigen following RP. Further research is required to define the safety of T therapy in men with PCa. However, many patients symptomatic from T deficiency are willing to accept the potential risk of PCa progression or recurrence in return for the opportunity to live a fuller and happier life with T therapy.

Testosterone Replacement Therapy in Hypogonadal Men Following Prostate Cancer Treatment: A Questionnaire-Based Retrospective Study among Urologists in Bavaria, Germany

Background: Several reports suggest testosterone replacement therapy (TRT) may be an option in selected hypogonadal patients with a history of prostate cancer (PCa) and no evidence of disease after curative treatment. Our aim was to assess TRT experience and patient management among urologists in Bavaria. Materials and Methods: Questionnaires were developed and mailed to all registered urologists in Bavaria (n = 420) regarding their experience with TRT in patients with treated PCa. Results: One hundred and ninety-three (46%) urologists returned the questionnaire and reported their experience with TRT in hypogonadal patients after curative treatment for PCa. Complete data was available for 32 men. Twenty-six patients (81%) received TRT after prostatectomy, 1 patient after external beam radiation, 3 patients after high-dose brachytherapy and 2 patients after high-intensity focused ultrasound. Of the PCa cases, 88.5% (23/26) were organ confined (pT2a-c), and 3 were pT3 tumors. All patients were pN0/cN0, and only 1 patient (pT3a) had a positive surgical margin status postoperatively. After a mean follow-up of 39.8 months, no biochemical relapse was observed. Conclusion: To date, there is no clear evidence to withhold TRT from hypogonadal men after curative PCa treatment. Our findings, although with limitations, fit in with the available data showing that TRT does not put patients at an increased risk after curative treatment of PCa.

Current state of practice regarding testosterone supplementation therapy in men with prostate cancer

Hypogonadal men are characterized by low serum testosterone and symptoms of low energy, decreased libido, and muscle mass as well as impaired concentration and sexual functioning. Men with prostate cancer (PCa) currently on active surveillance or post-therapy, have traditionally been excluded from management paradigms given the decade-old concern that testosterone caused PCa growth. However, there appears to be little or no relationship between serum testosterone concentration and PCa. Androgen action in the prostate has long been known to be affected by the kinetics of receptor saturation and, as such, testosterone beyond a certain baseline is unable to stimulate prostatic growth due to complete intra-prostatic androgen receptor binding. Given this physiologic concept, many clinical investigators have begun to promote testosterone supplementation therapy (TST) as safe in men with PCa. This review examines the basics of testosterone physiology and summarizes the most recent findings on the use of TST in men with PCa on active surveillance and following treatment with external beam radiotherapy, brachytherapy and radical prostatectomy.

Testosterone and the Prostate

INTRODUCTION

Late-onset hypogonadism, lower urinary tract symptoms (LUTS) due to benign prostatic enlargement (BPE), and prostate cancer commonly coexist in the aging male. Due to a better understanding of the physiology and impact of testosterone on benign and malignant diseases of the prostate, the view toward testosterone replacement therapy (TRT) in these individuals has changed dramatically over time.

AIM

This communication evaluates the effects of testosterone on benign prostatic growth and prostate cancer and reviews the evidence for TRT for men with BPE and prostate cancer.

METHODS

A literature review was performed with regards to TRT in men with prostate cancer as well as the effect of testosterone on the growth of benign prostate tissue and prostate cancer carcinogenesis.

MAIN OUTCOME MEASURE

To evaluate the evidence for an effect of testosterone on the growth of benign prostate tissue and the development of prostate cancer and TRT in men with prostate cancer.

RESULTS

TRT does not exacerbate LUTS. Current evidence is lacking but suggests that TRT may not increase the risk of subsequent diagnosis of prostate cancer, and is unlikely to impact recurrence or progression for men with treated prostate cancer, but longer follow-up is needed.

CONCLUSIONS

There is no evidence to suggest that TRT is contraindicated in men with BPE or effectively treated prostate cancer. Tan RBW, Silberstein JL, and Hellstrom WJG. Testosterone and the prostate. Sex Med Rev 2014;2:112-120.

The safety of testosterone supplementation therapy in prostate cancer

Patients with prostate cancer can present with hypogonadism and experience health and quality-of-life declines related to low testosterone levels. Despite generations of urological dogma suggesting that testosterone supplementation therapy (TST) for hypogonadism causes prostate-cancer progression, a review of the contemporary literature provides evidence to the contrary. The prostate saturation model suggests that the androgen receptor (AR) is saturated at serum testosterone levels of 150-200 ng/dl, and that additional serum testosterone above this level has limited, if any, effects within the prostate. Indeed, studies in the modern era of PSA assessments indicate that TST does not affect prostate size, intraprostatic testosterone levels, or prostate-cancer progression, provided the baseline serum testosterone level is greater than this AR saturation point. However, the body of data on this subject comes from a small number of cases, and TST should only be administered to patients with prostate cancer after thorough discussions of the risks and benefits, with subsequent careful monitoring.

Serum testosterone level, testosterone replacement treatment, and prostate cancer

There has been an increase in the number of individuals seeking testosterone (T) replacement treatment (TRT) due to a decrease in their blood T levels. Prostate cancer (PCa) is also an important issue in the same age group. However, we, urologists, are anxious about PCa development after T treatment. This is because it has been assumed that T may cause PCa or exacerbate insidious PCa which is already present. In this paper, recent developments regarding the relationship between serum levels of sex hormone and prostate tissue, the causal relationship between T and development of PCa, the effect of TRT on the group of patients who are at high risk of developing PCa, the suitability of TRT for patients who have already been diagnosed with PCa, and the effect of TRT on serum prostate-specific antigen level are analyzed.

A new era of testosterone and prostate cancer: from physiology to clinical implications

CONTEXT

Decades-old beliefs regarding androgens and prostate cancer (PCa) have undergone dramatic shifts in light of modern evidence and new theoretical constructs, but considerable confusion remains on this topic, particularly with regard to the use of testosterone therapy in men with any history of PCa.

OBJECTIVE

To review current literature regarding the relationship of serum testosterone on PCa and in particular the effect of testosterone therapy on PCa progression and recurrence.

EVIDENCE ACQUISITION

A Medline search was conducted to identify all original and review articles assessing the effect of androgens on the prostate and the use of testosterone in men with a history of treated and untreated PCa.

EVIDENCE SYNTHESIS

Contrary to traditional teaching, high endogenous serum testosterone does not increase the risk of developing PCa, and low serum testosterone does not protect against PCa. Although limited in size and duration, current studies similarly fail to indicate any increased risk of PCa in men receiving testosterone therapy. These results indicate a finite ability of androgens to stimulate PCa growth (the saturation model). A majority of studies demonstrate an association between low serum testosterone and poor prognostic features of PCa, including high-grade disease, advanced pathologic stage, and increased risk of biochemical recurrence following radical prostatectomy. The prostate-specific antigen-to-testosterone ratio predicted PCa risk in several biopsy studies. Multiple reports of testosterone therapy in men after treatment for localized PCa have shown low or absent recurrence rates. Some men with untreated PCa have received testosterone therapy without evidence for PCa progression.

CONCLUSIONS

The long-held belief that PCa risk is related to high serum androgen concentrations can no longer be supported. Current evidence indicates that maximal androgen-stimulated PCa growth is achieved at relatively low serum testosterone concentrations. It may therefore be reasonable to consider testosterone therapy in selected men with PCa and symptomatic hypogonadism.

Benefits and Consequences of Testosterone Replacement Therapy: A Review

Late onset hypogonadism (LOH) is an issue of increasing concern. Studies have shown the importance of testosterone in the maintenance of homeostasis, especially with respect to bone health, sexual function, diabetes, cardiovascular risk, mental health and cognition. Much of the dysfunction in hypogonadism can be reversed or improved with testosterone replacement therapy (TRT). Physicians worry about the possible consequences of TRT, especially regarding the prostate. By reviewing the literature, we have found there are significant benefits to TRT, and fears of adverse effects on the prostate are largely unfounded, though there is a great need for larger studies with longer periods of follow-up, especially to evaluate adverse events.

Risques prostatiques de la testostérone : nouveau retour du balancier?

Depuis les années 1940, la testostérone (T) est réputée dangereuse pour la prostate, bien que sans preuve solide. Les études longitudinales ne montrent pas de corrélation entre taux de T et incidence des cancers de la prostate (CaP), dont les formes graves sont au contraire associées à des taux faibles de cette hormone. Les essais cliniques randomisés contre placebo de traitement par la T n’ont pas montré d’augmentation de l’incidence du CaP dans les groupes T. Ces données rassurantes ont conduit certains à prescrire des traitements de substitution androgénique à des hommes porteurs de néoplasies intra-épithéliales prostatiques, ou précédemment traités pour un CaP de bon pronostic, ou sous surveillance active pour un tel cancer non traité, sans qu’apparaisse un risque élevé de progression ou de récidive du CaP sous ce traitement. Il ne fait pourtant aucun doute que la prostate normale et son cancer, au moins dans ses formes évoluées, sont faits de tissus androgénodépendants. Ces apparentes contradictions pourraient s’expliquer, outre par la possibilité d’une très faible diffusion de la T circulante dans le tissu prostatique, par l’hypothèse d’une saturation des récepteurs androgéniques prostatiques dès des niveaux très bas de T circulante, proches des taux de castration, expliquant qu’une augmentation de la T au-delà de ce niveau ne puisse pas stimuler le tissu prostatique. Quelques publications récentes d’évolution de CaP sous traitement androgénique, persistant parfois à l’arrêt de ce traitement, montrent qu’on ne peut pas généraliser les résultats très favorables des études précédentes. Des données objectives suggèrent aussi que le niveau de saturation du récepteur androgénique prostatique pourrait être en réalité proche de la limite inférieure des taux physiologiques de T. Il faut donc rester prudent avant d’élargir les indications du traitement par la T chez les hommes avec antécédent de CaP. Seules des études randomisées à grande échelle, en double insu contre placebo, permettront de se faire une idée exacte des risques auxquels expose ce traitement.