Current management of metastatic castration-sensitive prostate cancer

Treatment intensification in metastatic castration-sensitive prostate cancer: a real-world study in Alberta, Canada

AIM

To assess the current status of and factors associated with treatment intensification (TI) (with androgen receptor pathway inhibitors [ARPIs] and/or docetaxel) for metastatic castration-sensitive prostate cancer (mCSPC) in Canada.

MATERIALS & METHODS

Retrospective analysis of data for 431 patients with mCSPC from the Alberta Prostate Cancer Research Initiative database (July 2014-March 2022). The primary objective was to assess the patient proportion receiving TI, time to TI, and associated factors. The secondary and exploratory objectives were evaluating TI patterns and factors associated with choice of therapy, respectively.

RESULTS

Overall, 42% of patients received TI; most (65%) within 3 months post-index. TI was likely to occur within 3 months post-index in de novo mCSPC, but occurred later for recurrent mCSPC. Patients with recurrent mCSPC (HR [95% CI]: 0.52 [0.38-0.72]) and those aged ≥ 75 years (0.57 [0.36-0.93]) were less likely to receive TI. Patients with multiple metastatic sites and bone metastasis had a 2-3-fold higher likelihood of receiving TI. An ARPI was predominantly used (75%) for TI (median duration: 16.0 months).

CONCLUSION

TI rates for mCSPC are suboptimal in Canada especially for older patients and those with recurrent mCSPC. TI prioritization in such groups may improve patient outcomes.

Comparison of Short-Term Outcomes and Safety Profiles between Androgen Deprivation Therapy+Abiraterone/Prednisone and Androgen Deprivation Therapy+Docetaxel in Patients with De Novo Metastatic Hormone-Sensitive Prostate Cancer

PURPOSE

This study aimed to compare the short-term outcomes and safety profiles of androgen-deprivation therapy (ADT)+abiraterone/prednisone with those of ADT+docetaxel in patients with de novo metastatic hormone-sensitive prostate cancer (mHSPC).

MATERIALS AND METHODS

A web-based database system was established to collect prospective cohort data for patients with mHSPC in Korea. From May 2019 to November 2022, 928 patients with mHSPC from 15 institutions were enrolled. Among these patients, data from 122 patients who received ADT+abiraterone/prednisone or ADT+docetaxel as the primary systemic treatment for mHSPC were collected. The patients were divided into two groups: ADT+abiraterone/prednisone group (n=102) and ADT+docetaxel group (n=20). We compared the demographic characteristics, medical histories, baseline cancer status, initial laboratory tests, metastatic burden, oncological outcomes for mHSPC, progression after mHSPC treatment, adverse effects, follow-up, and survival data between the two groups.

RESULTS

No significant differences in the demographic characteristics, medical histories, metastatic burden, and baseline cancer status were observed between the two groups. The ADT+abiraterone/prednisone group had a lower prostate-specific antigen (PSA) progression rate (7.8% vs. 30.0%; p=0.011) and lower systemic treatment discontinuation rate (22.5% vs. 45.0%; p=0.037). No significant differences in adverse effects, oncological outcomes, and total follow-up period were observed between the two groups.

CONCLUSIONS

ADT+abiraterone/prednisone had lower PSA progression and systemic treatment discontinuation rates than ADT+docetaxel. In conclusion, further studies involving larger, double-blinded randomized trials with extended follow-up periods are necessary.

Metastatic Hormone-Sensitive Prostate Cancer and Combination Treatment Outcomes: A Review

Importance

Metastatic hormone-sensitive prostate cancer is currently an incurable disease. Despite a high response rate to androgen-deprivation therapy, most cases progress to castration-resistant disease, the terminal phase. This review provides a summary of the most recent evidence for current and emerging management strategies, including treatment intensification with combinations of therapies. It also provides recommendations on applying the evidence in clinical practice to encourage appropriate treatment to improve survival outcomes among patients with metastatic hormone-sensitive prostate cancer.

Observations

Androgen-deprivation therapy is the backbone of treatment for metastatic hormone-sensitive prostate cancer; however, it is insufficient alone to provide sustained disease control and long-term survival. Addition of an androgen receptor pathway inhibitor and/or docetaxel significantly improves survival, as demonstrated by several international phase 3 randomized clinical trials. Triplet therapy composed of androgen-deprivation therapy plus an androgen receptor pathway inhibitor plus docetaxel has been shown to improve overall survival over androgen-deprivation therapy plus docetaxel. In the ARASENS trial (darolutamide), the hazard ratios (HRs) were 0.68 (95% CI, 0.57-0.80) in the overall population; 0.71 (95% CI, 0.59-0.85) and 0.61 (95% CI, 0.35-1.05) in patients with de novo and recurrent disease, respectively; 0.69 (95% CI, 0.57-0.82) and 0.72 (95% CI, 0.41-1.13) in patients with high-volume and low-volume disease, respectively; and 0.71 (95% CI, 0.58-0.86) and 0.62 (95% CI, 0.42-0.90) in patients with high-risk and low-risk disease, respectively. In the PEACE-1 trial (abiraterone acetate + prednisone), the HRs were 0.75 (95% CI, 0.59-0.95; all de novo) in the overall population and 0.72 (95% CI, 0.55-0.95) and immature in the high-volume and low-volume subgroups, respectively. In the ENZAMET trial (enzalutamide), the HRs were 0.82 (95% CI, 0.63-1.06) in the overall population; 0.73 (95% CI, 0.55-0.99) and 1.10 (95% CI, 0.65-1.86) in the de novo and recurrent subgroups, respectively; and 0.87 (95% CI, 0.66-1.17) and 0.61 (95% CI, 0.33-1.10) in the high-volume and low-volume subgroups. Combination regimens are generally well tolerated, with adverse effects dependent on the profiles of the component drugs.

Conclusions and relevance

The findings of this review show compelling evidence from phase 3 randomized clinical trials in favor of initiating triplet combination therapy for patients with metastatic hormone-sensitive prostate cancer for the best overall survival. Patients who are eligible for chemotherapy should be offered androgen-deprivation therapy plus an androgen receptor pathway inhibitor plus docetaxel, particularly patients with high-volume, high-risk, or de novo metastatic disease.

Prognostic Role of Dynamic Changes in Serological Markers in Metastatic Hormone Naïve Prostate Cancer

We investigated whether inter-patient variation in the dynamic trajectory of hemoglobin (Hb), neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), lymphocyte to monocyte ratio (LMR), and prostate-specific antigen (PSA) can prognosticate overall survival (OS) in de novo mHSPC. This is a secondary analysis of the LATITUDE trial in which high-risk de novo mHSPC patients were randomly assigned to receive either androgen deprivation therapy (ADT) plus abiraterone or ADT plus placebo. We used a five-fold cross-validated joint model approach to determine the association of temporal changes in the serological markers with OS. Decision curve analysis was applied to determine the net benefit. When dynamic changes in Hb, LMR, NLR, PLR, and PSA were included in a multivariate joint model, an increase in the log of the current value of PSA (HR: 1.24 [1.20-1.28]) was associated with inferior OS. A multivariate joint model that captured dynamic trajectory of Hb, NLR, PLR, LMR, and PSA up to 24 months, showed a net benefit over the "treat all" strategy at a threshold of probability of approximately ≥30% while no net benefit was seen when dynamic change in PSA was omitted. Our joint model could be used for designing future adaptive trials investigating sequential treatment personalization.

Association of dynamic change in patient-reported pain with survival in metastatic castrate sensitive prostate cancer-exploratory analysis of LATITUDE study

BACKGROUND

Pain is an important dimension of quality-of-life in patients with metastatic castrate-sensitive prostate cancer (mCSPC). However, it is unclear if dynamic change in pain over time can predict for overall survival (OS) or progression-free survival (PFS) in these patients.

METHODS

This is an exploratory analysis of LATITUDE, a phase III randomized study, in which men with de novo mCSPC were randomized to receive either ADT plus abiraterone versus ADT alone. Information was collected on patient-reported worst pain score (WPS) and pain-interference score (PIS) from the Brief Pain Inventory-Short Form. A Bayesian joint modelling approach was used determine the association of dynamic change in WPS and PIS with OS and PFS.

RESULTS

Overall, 1125 patients with at least 3 measurements on pain scores were eligible. On Cox multivariable regression, increase in baseline WPS was associated with inferior OS (hazard ratio [HR] 1.049 [95% confidence intervals [CI] 1.015-1.085]; time dependent area under curve [tAUC] 0.64) and PFS (HR 1.045 [1.011-1.080]; tAUC: 0.64). Increase in baseline PIS was associated with inferior OS (HR 1.062 [1.020-1.105]; tAUC: 0.63) but not with PFS (HR 1.038 [0.996-1.08]). On independent joint models, an increase in the current value of WPS by 1-unit was associated with inferior OS (HR 1.316 [1.258-1.376]; tAUC 0.74) and PFS (HR 1.319 [1.260-1.382]; tAUC 0.70). Similar association was seen for increase in the current value of PIS with OS (HR 1.319 [1.261-1.381]; tAUC 0.73) and PFS (HR 1.282 [1.224-1.344]; tAUC 0.73).

CONCLUSIONS

The above findings highlight the potential dynamic interplay between patient-reported pain with OS and PFS in mCSPC. Compared to baseline pain, such dynamic assessment of pain was found to have superior predictive ability and thus has the potential to tailor subsequent treatment based on response to initial therapy beyond its role as a very important dimension of quality-of-life.

Magmas Inhibition in Prostate Cancer: A Novel Target for Treatment-Resistant Disease

Simple Summary

Metastatic and treatment-resistant prostate cancer remains a life-threatening disease despite recent therapeutic advances. Literature suggests that treatment resistance and prostate cancer progression is associated with prostate cancer stem cells. In this study, we evaluated the role of the mitochondria-associated granulocyte–macrophage colony-stimulating factor signaling (Magmas) protein as a molecular target and applied a novel Magmas inhibitor, BT#9, on prostate cancer cells and normal control cells. We found that Magmas was overexpressed in human prostate cancers and its expression was linked to the aggressiveness of the disease. BT#9 downregulated Magmas expression, reduced viability and induced apoptotic cell death in prostate cancer cells. The mechanism of cell death by BT#9 is mainly caspase-independent and via a Reactive Oxygen Species (ROS)-mediated pathway. This is the first study that has evaluated targeting the Magmas protein in prostate cancer and, to our knowledge, the first to elucidate the potential molecular mechanism of BT#9 activity in prostate cancer, including the mode of cell death and the critical role of ROS accumulation. Our work may provide a potential clinical application for a novel prostate cancer treatment that can overcome cancer stem cell and therapeutic resistance.

Abstract

The purpose of our study was to evaluate Magmas as a potential target in prostate cancer. In addition, we evaluated our synthetic Magmas inhibitor (BT#9) effects on prostate cancer and examined the molecular mechanism of BT#9. A cell viability assay showed that treatment with BT#9 caused a significant decrease in the viability of DU145 and PC3 prostate cancer cells with little effect on the viability of WPMY-1 normal prostate cells. Western blot proved that BT#9 downregulated the Magmas protein and caspase-3 activation. Flow cytometry studies demonstrated increased apoptosis and disturbed mitochondrial membrane potential. However, the main mode of cell death was caspase-independent necrosis, which was correlated with the accumulation of mitochondrial and intra-cellular Reactive Oxygen Species (ROS). Taken together, our data suggest Magmas is a potential molecular target for the treatment of prostate cancer and that Magmas inhibition results in ROS-dependent and caspase-independent necrotic cell death.