Testosterone monitoring for men with advanced prostate cancer: Review of current practices and a survey of Canadian physicians

Adaptive Treatment of Metastatic Prostate Cancer Using Generative Artificial Intelligence

Despite the expanding therapeutic options available to cancer patients, therapeutic resistance, disease recurrence, and metastasis persist as hallmark challenges in the treatment of cancer. The rise to prominence of generative artificial intelligence (GenAI) in many realms of human activities is compelling the consideration of its capabilities as a potential lever to advance the development of effective cancer treatments. This article presents a hypothetical case study on the application of generative pre-trained transformers (GPTs) to the treatment of metastatic prostate cancer (mPC). The case explores the design of GPT-supported adaptive intermittent therapy for mPC. Testosterone and prostate-specific antigen (PSA) are assumed to be repeatedly monitored while treatment may involve a combination of androgen deprivation therapy (ADT), androgen receptor-signalling inhibitors (ARSI), chemotherapy, and radiotherapy. The analysis covers various questions relevant to the configuration, training, and inferencing of GPTs for the case of mPC treatment with a particular attention to risk mitigation regarding the hallucination problem and its implications to clinical integration of GenAI technologies. The case study provides elements of an actionable pathway to the realization of GenAI-assisted adaptive treatment of metastatic prostate cancer. As such, the study is expected to help facilitate the design of clinical trials of GenAI-supported cancer treatments.

Adherence to oral hormonal therapy in advanced prostate cancer: a scoping review

Background

Orally administrated agents play a key role in the management of prostate cancer, providing a convenient and cost-effective treatment option for patients. However, they are also associated with adherence issues which can compromise therapeutic outcomes. This scoping review identifies and summarizes data on adherence to oral hormonal therapy in advanced prostate cancer and discusses associated factors and strategies for improving adherence.

Methods

PubMed (inception to 27 January 2022) and conference databases (2020-2021) were searched to identify English language reports of real-world and clinical trial data on adherence to oral hormonal therapy in prostate cancer using the key search terms 'prostate cancer' AND 'adherence' AND 'oral therapy' OR respective aliases.

Results

Most adherence outcome data were based on the use of androgen receptor pathway inhibitors in metastatic castration-resistant prostate cancer (mCRPC). Self-reported and observer-reported adherence data were used. The most common observer-reported measure, medication possession ratio, showed that the vast majority of patients were in possession of their medication, although proportion of days covered and persistence rates were considerably lower, raising the question whether patients were consistently receiving their treatment. Study follow-up for adherence was generally around 6 months up to 1 year. Studies also indicate that persistence may drop further with longer follow-up, especially in the non-mCRPC setting, which may be a concern when years of therapy are required.

Conclusions

Oral hormonal therapy plays an important role in the treatment of advanced prostate cancer. Data on adherence to oral hormonal therapies in prostate cancer were generally of low quality, with high heterogeneity and inconsistent reporting across studies. Short study follow-up for adherence and focus on medication possession rates may further limit relevance of available data, especially in settings that require long-term treatment. Additional research is required to comprehensively assess adherence.

Immunocastration in adult boars as a model for late-onset hypogonadism

Background

While immunocastration has been studied in male pre‐pubertal pigs, data on older, sexually mature animals are limited. To understand the physiological effects of androgen deprivation in the late sexual development phase, we compared mature immunocastrated boars (n = 19; average age = 480 days) to young male immunocastrated pigs (n = 6; average age = 183 days) and young entire males (n = 6; average age = 186 days) as positive and negative controls, respectively.

Objectives

We hypothesized that the timing of gonadotropin‐releasing hormone suppression (early or late sexual development phases) influences the extent of reproductive function inhibition, histological structure of testicular tissue, and expression levels of selected genes related to steroid metabolism.

Materials and methods

Antibody titer, hormonal status, and histomorphometric analysis of testicular tissue were subjected to principal component analysis followed by hierarchical clustering to evaluate the immunocastration effectiveness in mature boars.

Results

Hierarchical clustering differentiated mature immunocastrated boars clustered with young immunocastrated pigs from those clustered with entire males. Although all mature immunocastrated boars responded to vaccination, as evidenced by the increased gonadotropin‐releasing hormone antibody titers (p < 0.001), decreased serum luteinizing hormone concentrations (p = 0.002), and changes in testicular tissue vascularization (lighter and less red testicular parenchyma; p ≤ 0.001), the responses were variable. Sharp decreases in testes index (p < 0.001), Leydig cell volume density (p < 0.001), Leydig cell nucleus‐to‐cytoplasm ratio (p < 0.001), and testosterone concentration (p < 0.001) were observed in mature immunocastrated boars clustered with young immunocastrated pigs compared with those that clustered with entire males. Additionally, mature immunocastrated boars clustered with young immunocastrated pigs showed lower hydroxysteroid 17‐beta dehydrogenase 7 expression than entire males (p < 0.05). The young immunocastrated pigs group showed higher follicle‐stimulating hormone receptors than the entire males and mature immunocastrated boars, lower steroidogenic acute regulatory protein expression levels compared with entire males, and mature immunocastrated boars clustered with entire males (p < 0.01).

Conclusion

The two‐dose vaccination regime resulted in progressive but variable regression of testicular function in adult (post‐pubertal) pigs; however, it was insufficient to induce a complete immunocastration response in all animals.

[Management of testosterone in advanced hormone-sensitive prostate cancer: still up to date?]

Androgen-deprivation therapy (ADT) is the standard therapy used for advanced or metastatic prostate cancer, either alone or in association with additional procedures and substances. The optimum value of testosterone postulated more than 40 years ago was arbitrarily set to be < 50 ng/dL or < 1.7 nmol/L and, from today's perspective, was defined by more insensitive measurement methods. Since then, more and more data has been generated, suggesting that a value of < 20 ng/dL would be prognostically relevant. Yet no guideline has been changed so far despite the call for lowering the target value. Measuring testosterone to evaluate the response to androgen suppression is not yet established in clinical routine. There are no specific recommendations in national and international guidelines. Based on the evolving evidence, the question about testosterone management during ADT is gaining importance. The current data is summarised in this paper.

Different androgen deprivation therapies might have a differential impact on cognition - An analysis from a population-based study using time-dependent exposure model

BACKGROUND

Androgen deprivation therapy (ADT) remains the mainstay treatment for locally advanced or metastatic prostate cancer (PC). However, potential effects of ADT treatment on neurocognitive dysfunction remain unclear. The present study was conducted to assess the relation between ADT treatment and risk of cognitive decline in Asian men with PC.

METHODS

A population-based cohort of 24,464 men with PC, each newly diagnosed between 2000 and 2008, was selected from the Taiwan National Health Insurance Database. Subjects were further grouped by treatment as non-ADT (n = 4685) or ADT (n = 12,740), members of the latter subjected to bilateral orchiectomy or medical treatment (ie, luteinizing hormone-releasing hormone agonists, antiandrogens, or combination therapy). A multivariable Cox proportional hazard model with ADT as time-dependent covariate was used to generate adjusted hazard ratios (HRs) of subsequent cognitive decline, including dementia, Alzheimer's disease (AD), and Parkinson's disease (PD).

RESULTS

ADT showed a significant association with overall risk of cognitive decline (HR = 1.51, 95 % CI: 1.31-1.74), especially for PD, dementia, and non-Alzheimer dementia (non-AZD). When stratified by various ADT regimens, antiandrogen-only recipients displayed significantly heightened risks of subsequent AD, non-AZD, and PD. However, combined androgen blockade also imposed an increased risk of PD. There was no apparent correlation between duration of ADT exposure and cognitive dysfunction.

CONCLUSIONS

Various ADT therapies may have disparate impacts on cognitive function. Prospective studies exploring pertinent clinical characteristics more fully are needed to confirm these findings.

Discordance between testosterone measurement methods in castrated prostate cancer patients

Failure to suppress testosterone below 0.7 nM in castrated prostate cancer patients is associated with poor clinical outcomes. Testosterone levels in castrated patients are therefore routinely measured. Although mass spectrometry is the gold standard used to measure testosterone, most hospitals use an immunoassay method. In this study, we sought to evaluate the accuracy of an immunoassay method to measure castrate testosterone levels, with mass spectrometry as the reference standard. We retrospectively evaluated a cohort of 435 serum samples retrieved from castrated prostate cancer patients from April to September 2017. No follow-up of clinical outcomes was performed. Serum testosterone levels were measured in the same sample using liquid chromatography coupled with tandem mass spectrometry and electrochemiluminescent immunoassay methods. The mean testosterone levels were significantly higher with immunoassay than with mass spectrometry (0.672 ± 0.359 vs 0.461 ± 0.541 nM; P < 0.0001). Half of the samples with testosterone ≥0.7 nM assessed by immunoassay were measured <0.7 nM using mass spectrometry. However, we observed that only 2.95% of the samples with testosterone <0.7 nM measured by immunoassay were quantified ≥0.7 nM using mass spectrometry. The percentage of serum samples experiencing testosterone breakthrough at >0.7 nM was significantly higher with immunoassay (22.1%) than with mass spectrometry (13.1%; P < 0.0001). Quantitative measurement of serum testosterone levels >0.7 nM by immunoassay can result in an inaccurately identified castration status. Suboptimal testosterone levels in castrated patients should be confirmed by either mass spectrometry or an immunoassay method validated at low testosterone levels and interpreted with caution before any changes are made to treatment management.

Testosterone suppression in the treatment of recurrent or metastatic prostate cancer - A Canadian consensus statement

Testosterone suppression, achieved through orchiectomy or medically induced androgen-deprivation therapy (ADT), is a standard treatment for men with recurrent and metastatic prostate cancer. Current assay methods demonstrate the capacity for testosterone suppression to <0.7 nmol/l, and clinical data support improved outcomes from ADT when lower levels are achieved. Practical clinical guidelines are warranted to facilitate adoption of 0.7 nmol/l as the new standard castrate testosterone level.A pan-Canadian group of experts, representing diverse clinical specialties, identified key clinical issues, searched and reviewed relevant literature, and developed consensus statements on testosterone suppression for the treatment of prostate cancer. The expert panel found that current evidence supports the clinical benefit of achieving low testosterone levels during ADT, and encourage adoption of ≤0.7 nmol/l as a new castrate level threshold. The panel recommends regular monitoring of testosterone (e.g., every 3-6 months) and prostate-specific antigen (PSA) levels as clinically appropriate (e.g., every 3-6 months) during ADT, with reassessment of therapeutic strategy if testosterone is not suppressed or if PSA rises regardless of adequate testosterone suppression. The panel also emphasizes the need for greater awareness and education regarding testosterone assay specifications, and strongly promotes the use of mass spectrometry-based assays to ensure accurate measurement of testosterone at castrate levels.