Guilt by Association: A Historical Perspective on Huggins, Testosterone Therapy, and Prostate Cancer

Testosterone replacement therapy is not associated with increased prostate cancer incidence, prostate cancer-specific, or cardiovascular disease-specific mortality in Finnish men

BACKGROUND

Concerns have been expressed over the safety of testosterone replacement therapy (TRT) in men with late-onset hypogonadism (LOH). Previous studies have shown controversial results regarding the association of TRT with the risk of cardiovascular events or prostate cancer (PCa) incidence, aggressiveness, and mortality. This study explores the overall risk of PCa and risk by tumor grade and stage, as well as mortality from PCa and cardiovascular disease (CVD), among men treated with TRT compared to men without LOH and TRT use.

MATERIALS AND METHODS

The study included 78,615 men of age 55-67 years at baseline from the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC). Follow-up started at randomization and ended at death, emigration, or a common closing date January 1st, 2017. Cox proportional hazards regression model with time-dependent variables and adjustment for age, trial arm, use of other medications, and Charlson comorbidity index was used. Comprehensive information on TRT purchases during 1995-2015 was obtained from the Finnish National Prescription Database. PCa cases were identified from the Finnish Cancer Registry and causes of death obtained from Statistics Finland.

RESULTS

Over the course of 18 years of follow-up, 2919 men were on TRT, and 285 PCa cases were diagnosed among them. TRT users did not exhibit a higher incidence or mortality rate of PCa compared to non-users. On the contrary, men using TRT had lower PCa mortality than non-users (HR = 0.52; 95% CI 0.3-0.91). Additionally, TRT users had slightly lower CVD and all-cause mortality compared to non-users (HR = 0.87; 95% CI 0.75-1.01 and HR = 0.93; 95% CI 0.87-1.0, respectively). No time- or dose-dependency of TRT use was evident in any of the analyses.

CONCLUSION

Men using TRT were not associated to increased risk for PCa and did not experience increased PCa- or CVD-specific mortality compared to non-users. Further studies considering blood testosterone levels are warranted.

Association between genetically proxied HMGCR inhibition and male reproductive health: A Mendelian randomization study

BACKGROUND

The causal associations between statin use and male sex hormone levels and related disorders have not been fully understood. In this study, we employed Mendelian randomization for the first time to investigate these associations.

METHODS

In two-sample Mendelian randomization framework, genetic proxies for hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) inhibition were identified as variants in the HMGCR gene that were associated with both levels of gene expression and low density lipoprotein cholesterol (LDL-C). We assessed the causal relationship between HMGCR inhibitor and 5 sex hormone levels/2 male-related diseases. Additionally, we investigated the association between 4 circulating lipid traits and outcomes. The "inverse variance weighting" method was used as the primary approach, and we assessed for potential heterogeneity and pleiotropy. In a secondary analysis, we revalidated the impact of HMGCR on 7 major outcomes using the summary-data-based Mendelian randomization method.

RESULTS

Our study found a significant causal association between genetic proxies for HMGCR inhibitor and decreased levels of total testosterone (TT) (LDL-C per standard deviation = 38.7mg/dL, effect = -0.20, 95% confidence interval [CI] = -0.25 to -0.15) and bioavailable testosterone (BT) (effect = -0.15, 95% CI = -0.21 to -0.10). Obesity-related factors were found to mediate this association. Furthermore, the inhibitor were found to mediate a reduced risk of prostate cancer (odds ratio = 0.81, 95%CI = 0.7-0.93) by lowering bioavailable testosterone levels, without increasing the risk of erectile dysfunction (P = .17). On the other hand, there was a causal association between increased levels of LDL-C, total cholesterol, triglycerides (TG) and decreased levels of TT, sex hormone-binding globulin, and estradiol.

CONCLUSIONS

The use of HMGCR inhibitor will reduce testosterone levels and the risk of prostate cancer without the side effect of erectile dysfunction. LDL-C, total cholesterol, and TG levels were protective factors for TT, sex hormone-binding globulin, and estradiol.

Testosterone replacement in prostate cancer survivors with testosterone deficiency: Study protocol of a randomized controlled trial

BACKGROUND

Most men diagnosed with prostate cancer today have organ-confined disease and low risk of disease recurrence after radical prostatectomy. Testosterone deficiency in prostate cancer survivors contributes to impaired health-related quality of life but testosterone treatment is viewed as a contraindication in this population.

OBJECTIVES

We describe the design of the first randomized trial to determine the safety and efficacy of testosterone treatment in men who have undergone prostatectomy for non-aggressive prostate cancer and have symptomatic testosterone deficiency.

METHODS

Surviving Prostate cancer while Improving quality of life through Rehabilitation with Testosterone Trial is a randomized, placebo-controlled, double-blind, parallel group trial in 142 men, ≥ 40 years, who have undergone radical prostatectomy for organ-confined prostate cancer, Gleason score ≤ 7 (3+4), Stage pT2, N0, M0 lesions and have symptomatic testosterone deficiency and undetectable prostate specific antigen for > 2 years after surgery. Eligible participants are randomized to weekly intramuscular injections of 100-mg testosterone cypionate or placebo for 12 weeks and followed for another 12 weeks. Primary endpoint is change from baseline in sexual activity. Secondary outcomes include change in sexual desire, erectile function, energy, lean and fat mass, physical and cognitive performance. Safety is assessed by monitoring prostate-specific antigen, lower urinary tract symptoms, hemoglobin, and adverse events.

RESULTS

The trial is being conducted at two trial sites in Boston, MA and Baltimore, MD. As of July 30, 2022, 42 participants have been randomized. No prostate-specific antigen or clinical recurrence has been noted to-date.

DISCUSSION

Recruitment was slowed by coronavirus disease 2019-related closures, slow subsequent ramp-up of research activities, and patient concerns about safety of testosterone treatment. Despite these challenges, participant retention has been high.

CONCLUSION

The Surviving Prostate cancer while Improving quality of life through Rehabilitation with Testosterone Trial, a placebo-controlled, randomized trial, will determine whether testosterone replacement therapy is safe and efficacious in correcting symptoms of testosterone deficiency in prostate cancer survivors, and potentially inform clinical practice.

Genetically predicted testosterone and cancers risk in men: a two-sample Mendelian randomization study

OBJECTIVE

In observational studies, testosterone has been reported to be associated with some types of cancers. However, the direction and magnitude of the causal association between testosterone and different types of cancer remain unclear. This Mendelian randomization study assessed the causal associations of total testosterone (TT) and bioavailable testosterone (BT) with cancer risk in men.

METHODS

We performed two-sample Mendelian randomization using publicly available GWAS summary statistics to investigate the genetically causal association between testosterone and the risk of 22 kinds of cancers in men. Causal estimates were calculated by the inverse variance weighted method. We also performed additional sensitivity tests to evaluate the validity of the casualty.

RESULTS

Genetically predicted BT level were significantly associated with an increased risk of prostate cancer [odds ratio (OR) = 1.17 95% confidence interval (CI): 1.09-1.26, P = 2.51E-05] in the MR analysis with the IVW method. TT was found to be the suggestive protective factor against stomach cancer (OR = 0.66, 95% CI: 0.48-0.93, P = 0.0116) as well as pancreatic cancer (OR = 0.59, 95% CI: 0.36-0.96, P = 0.0346). A suggestive association was found between TT and the occurrence of small intestine cancer (OR = 1.0004, 95% CI: 1.0001-1.0007, P = 0.0116). However, testosterone had no significant association with other cancers.

CONCLUSION

This study investigated the role of testosterone in the development of prostate cancer, stomach cancer, pancreatic cancer, and small intestine cancer but found no strong association with the other cancers in men.

Questioning the evidence behind the Saturation Model for testosterone replacement therapy in prostate cancer

Published in 2009, the Saturation Model suggested that there were limits to which androgen encouraged growth of the prostate. This was, in particular, applied to prostate cancer, where conventional wisdom since Huggins has considered it almost taboo for a patient being treated with cancer to receive testosterone replacement therapy (TRT). Since then, several studies began to investigate the application of TRT in, at first, mild and stable prostate cancer patients. While early reports seem promising, the validity of the Saturation Model had not been addressed. The current review investigates the evidence synthesis behind the Saturation Model, based on its original publication where it was presented. The evidence reviewed includes in vitro, in vivo and clinical studies that were referenced as the basis when the model was presented. Despite promising associations, the evidence employed were troublingly taken out of context in many cases and applied freely in cases where it would be unwise to do so. In light of some shortcomings in evidence synthesis, we advise some caution when applying the Saturation Model 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.

[Antihormonal therapy in prostate cancer : Side effects]

Androgen deprivation is still standard therapy for prostate cancer, either as primary androgen deprivation therapy or with the use of secondary hormonal drugs including abiraterone and enzalutamide. However, especially the clinically occult side effects like metabolic changes or cardiovascular complications and effects on the psyche of the patient are often not recognized in daily practice. Active monitoring of such side effects is essential for prevention and early intervention. In addition, the efficacy of androgen deprivation therapies is limited by primary and secondary resistance. The underlying molecular mechanism including splice variants of the androgen receptor in contrast to mutations are usually reversible and should be regarded as a sign of efficacy of the current treatment. Therefore, the clever, timely use of androgen deprivation or even the use of a bipolar androgen therapy should enable reversal of resistance to again render tumor cells sensitive to androgen-deprivation therapy.

Preoperative hormonal pattern in patients undergoing radical prostatectomy due to prostate cancer

OBJECTIVE

There is controversial evidence regarding preoperative testosterone (T) levels related to poor prognosis factors after radical prostatectomy (RP). The aim of this manuscript is to determine the relationship between preoperative T levels and final pathologic report together to biochemical recurrence after RP.

MATERIALS AND METHODS

We prospectively analysed 143 patients submitted to RP from February 2008 to June 2010 in our centre. Pretreatment T and sex hormone-binding globulin levels were determined as part of our clinical protocol. Free calculated (fT) and bioavailable (bioT) T were calculated using Vermeulen's formula. Low T levels were defined as 346 ng/dL or less. A comparative analysis with variables pTNM, positive margins, tumour burden, Gleason score, multifocality and biochemical recurrence (using both PSA>0.4 ng/dL and PSA>0.2 ng/dL as cut-off values) was performed, according to preoperative levels of T.

RESULTS

Variables Gleason score, rate and number of positive margins, tumour burden, tumour multifocality, time to biochemical recurrence and pathological stage were not related to preoperative hormonal levels. Preoperative T<346 ng/dL was not found to be related to PSA recurrence (PSA>0,4 ng/dL log-rank, P=.512), although a trend was observed when PSA>0,2 ng/dL (log-rank, P=.097).

CONCLUSION

Preoperative T levels were not related to final pathological report or to biochemical recurrence.

Androgen metabolism and JAK/STAT pathway genes and prostate cancer risk

BACKGROUND

Prostate cancer (PC) is the most frequently diagnosed solid tumor in U.S. men. Genome-wide association studies (GWAS) have identified over 40 risk-associated single nucleotide polymorphisms (SNPs), including variants in androgen pathway genes (e.g., KLK3 and AR). Androgens are important in PC and genes involved in this pathway are therefore candidates for conferring susceptibility to PC.

METHODS

In this hypothesis-testing study, we evaluated PC risk in association with SNPs in 22 candidate genes involved in androgen metabolism or interactions with the androgen receptor (AR). A total of 187 SNPs were genotyped in 1458 cases and 1351 age-matched controls from a population-based study. PC risk was estimated using adjusted unconditional logistic regression and multinomial regression models.

RESULTS

Single SNP analyses showed evidence (p < 0.05) for associations with 14 SNPs in 9 genes: NKX3.1, HSD17B3, AKR1C3, SULT2A1, CYP17A1, KLK3, JAK2, NCOA4 and STAT3. The most significant result was observed for rs2253502 in HSD17B3 (odds ratio, OR = 0.57, 95% CI: 0.39-0.84). In addition, five SNPs in four genes (CYP17A1, HSD17B4, NCOA4, and SULT2A1) were associated with more aggressive disease (p < 0.01).

CONCLUSIONS

Our results replicate previously reported associations for SNPs in CYP17A1, HSD17B3, ARK1C3, NKX3.1, NCOA4 and KLK3. In addition, novel associations were observed for SNPs in JAK2, HSD17B4, and SULT2A1. These results will require replication in larger studies.

Is testosterone treatment good for the prostate? Study of safety during long-term treatment

INTRODUCTION

For men with androgen deficiency on testosterone replacement therapy (TRT), clinical concern relates to the development of prostate cancer (PCa).

AIM

An updated audit of prostate safety from the UK Androgen Study was carried out to analyze the incidence of PCa during long-term TRT.

MAIN OUTCOME MEASURES

Diagnosis of PCa in men receiving TRT, by serum prostate-specific antigen (PSA) testing and digital rectal examination (DRE), and its relation to different testosterone preparations.

METHODS

One thousand three hundred sixty-five men aged 28-87 (mean 55) years with symptomatic androgen deficiency and receiving TRT have been monitored for up to 20 years. All patients were prescreened for PCa by DRE and PSA along with endocrine, biochemical, hematological, and urinary profiles at baseline and every 6 months. Abnormal findings or rising PSA were investigated by transrectal ultrasound and prostate biopsy. The data were compared for the four different testosterone preparations used in TRT, including pellet implants, Restandol, mesterolone, and Testogel.

RESULTS

Fourteen new cases of PCa were diagnosed at one case per 212 years treatment, after 2,966 man-years of treatment (one case per 212 years). Time to diagnosis ranged from 1 to 12 years (mean 6.3 years). All tumors were clinically localized and suitable for potentially curative treatment. Initiating testosterone treatment had no statistically significant effect on total PSA, free PSA or free/total PSA ratio, and any initial PSA change had no predictive relationship to subsequent diagnosis of cancer.

CONCLUSIONS

The incidence of PCa during long-term TRT was equivalent to that expected in the general population. This study adds to the considerable weight of evidence that with proper clinical monitoring, testosterone treatment is safe for the prostate and improves early detection of PCa. Testosterone treatment with regular monitoring of the prostate may be safer for the individual than any alternative without surveillance.

Low testosterone levels are related to poor prognosis factors in men with prostate cancer prior to treatment

What's known on the subject? and What does the study add? Prostate growth is ruled by testosterone. Nevertheless, the paradigm that high testosterone levels induce prostate cancer development or lead to a poor prognosis in prostate cancer is not supported by evidence. A growing number of studies suggest that, on the contrary, low testosterone levels are related to poor prognosis features in prostate cancer such as higher prostate-specific antigen or higher Gleason score. Our experience shows that testosterone levels are related to risk of progression of prostate cancer - those men with lower testosterone levels are at higher risk of progression of their prostate cancer after treatment delivery.

OBJECTIVES

• Low testosterone levels have been related to a higher diagnosis of prostate cancer (PCa). Hormonal levels have been related to poor prognosis factors in men with PCa, mainly after radical prostatectomy. • Our aim was to determine the relationship between hormonal levels and PCa prognosis factors in men with PCa prior to the onset of treatment.

PATIENTS AND METHODS

• We prospectively analysed 137 males diagnosed in our centre with PCa with 5+5 core prostate biopsies from February 2007 to December 2009. • As part of our clinical protocol, we performed hormonal determination (testosterone and sex hormone binding globulin) following International Society of Andrology, International Society for the Study of the Aging Male and European Association of Urology recommendations. • Free testosterone and bioavailable testosterone were calculated using Vermeulen's formula. • Age, prostate-specific antigen (PSA), free to total PSA, PSA density, number of previous biopsies, digital rectal examination staging, Gleason score, percentage of tumour in the biopsy sample, bilaterality of the tumour and risk of progression group were prospectively recorded.

RESULTS

• Higher testosterone levels were related to lower digital rectal examination staging (P= 0.02) and lower PSA level (P= 0.05). Higher testosterone was not related to lower Gleason score (P= 0.08). • Testosterone was inversely related to PCa bilaterality (P < 0.01) and percentage of tumour in the biopsy (P < 0.01). • High testosterone levels were found in patients allocated to the low risk of progression group and inversely (P= 0.03). • In multivariate analysis, higher age and lower testosterone were related to higher D'Amico risk of progression.

CONCLUSION

• Patients with PCa and lower testosterone levels have poor prognosis factors and higher tumour burden before treatment onset. These findings reinforce the idea that low testosterone levels pretreatment are related to a poor prognosis in PCa.

Changes in prostate specific antigen in hypogonadal men after 12 months of testosterone replacement therapy: support for the prostate saturation theory

PURPOSE

We measured prostate specific antigen after 12 months of testosterone replacement therapy in hypogonadal men.

MATERIALS AND METHODS

Data were collected from the TRiUS (Testim® Registry in the United States), an observational registry of hypogonadal men on testosterone replacement therapy (849). Participants were Testim naïve, had no prostate cancer and received 5 to 10 gm Testim 1% (testosterone gel) daily.

RESULTS

A total of 451 patients with prostate specific antigen and total testosterone values were divided into group A (197 with total testosterone less than 250 ng/dl) and group B (254 with total testosterone 250 ng/dl or greater). The groups differed significantly in free testosterone and sex hormone-binding globulin, but not in age or prostate specific antigen. In group A but not group B prostate specific antigen correlated significantly with total testosterone (r=0.20, p=0.005), free testosterone (r=0.22, p=0.03) and sex hormone-binding globulin (r=0.59, p=0.002) at baseline. After 12 months of testosterone replacement therapy, increase in total testosterone (mean±SD) was statistically significant in group A (+326±295 ng/dl, p<0.001; final total testosterone 516±28 ng/dl) and group B (+154±217 ng/dl, p<0.001; final total testosterone 513±20 ng/dl). After 12 months of testosterone replacement therapy, increase in prostate specific antigen was statistically significant in group A (+0.19±0.61 ng/ml, p=0.02; final prostate specific antigen 1.26±0.96 ng/ml) but not in group B (+0.28±1.18 ng/ml, p=0.06; final prostate specific antigen 1.55±1.72 ng/ml). The average percent prostate specific antigen increase from baseline was higher in group A (21.9%) than in group B (14.1%). Overall the greatest prostate specific antigen was observed after 1 month of treatment and decreased thereafter.

CONCLUSIONS

Patients with baseline total testosterone less than 250 ng/dl were more likely to have an increased prostate specific antigen after testosterone replacement therapy than those with baseline total testosterone 250 ng/dl or greater, supporting the prostate saturation hypothesis. Clinicians should be aware that severely hypogonadal patients may experience increased prostate specific antigen after testosterone replacement therapy.