Association of time to prostate-specific antigen nadir and logarithm of prostate-specific antigen velocity after progression in metastatic prostate cancer with prior primary androgen deprivation therapy

Impact of PSA nadir, PSA response and time to PSA nadir on overall survival in real-world setting of metastatic hormone-sensitive prostate cancer patients

BACKGROUND

To evaluate the impact of prostate-specific antigen (PSA) nadir, PSA response and time to PSA nadir (TTN) in metastatic hormone-sensitive prostate cancer (mHSPC) patients on overall survival (OS) in the era of combination therapies.

METHODS

Different PSA nadir cut-offs (including ultra-low PSA) were tested for OS analyses. Additionally, PSA response ≥99% was evaluated, as well as TTN categorized as <3 versus 3-6 versus 6-12 versus >12 months. Multivariable Cox regression models predicted the value of PSA nadir cut-offs, PSA response and TTN on OS. Sensitivity analyses were performed in de novo and high volume mHSPC patients.

RESULTS

Of 238 eligible patients, PSA cut-offs of <0.2 versus 0.2-4.0 versus >4.0 ng/mL differed significantly regarding median OS (96 vs. 56 vs. 44 months, p < 0.01), as well as in subgroup analyses of de novo mHSPC patients and multivariable Cox regression models. A more stringent PSA cut-off of <0.02 versus 0.02-0.2 versus >0.2 ng/mL also yielded significant median OS differences (not reached vs. 96 vs. 50 months, p < 0.01), even after additional multivariable adjustment. A PSA response ≥99% was also significantly associated with better OS than counterparty with <99% response, even after multivariable adjustment (both p < 0.02). When TTN groups were compared, patients with longer TTN harbored more extended OS than those with short TTN (<3 vs. 3-6 vs. 6-12 vs. >12 months: 34 vs. 50 vs. 67 vs. 96 months, p < 0.01). Virtually similar results were observed in sensitivity analyses for high volume mHSPC patients.

CONCLUSIONS

In times of combination therapies for mHSPC, a PSA nadir of respectively, <0.2 and <0.02 ng/mL are associated with best OS rates. Moreover, a relative PSA response ≥99% and a longer TTN are clinical important proxies for favorable OS estimates.

Real-world retrospective study of prostate-specific antigen and safety assessment with darolutamide plus androgen deprivation therapy for metastasis hormone-sensitive prostate cancer

Background

ARASENS has demonstrated the efficacy and safety for darolutamide (DARO) with androgen deprivation therapy (ADT) plus docetaxel in metastasis hormone-sensitive prostate cancer (mHSPC). There is a lack of reports for DARO with ADT in mHSPC though the regimen is used in clinical from time to time. Moreover, recent studies have supported the importance of early and rapid prostate-specific antigen (PSA) reduction, which correlates with reduced disease progression and improved survival in patients with mHSPC. This study aims to evaluate PSA reduction as a primary endpoint for DARO with ADT in the treatment of mHSPC and to evaluate the real-world short-term PSA control of DARO with ADT from two leading medical centers in China.

Methods

We retrospectively reviewed the clinical records of patients with mHSPC receiving ADT and DARO (600 mg, b.i.d.). The collection of data spanned from March 1, 2022, to July 31, 2023. The main observation indicators were PSA level and drug-related adverse events (AE) after medication. PSA levels were closely monitored prior to treatment initiation and at 2-week intervals, as well as at 1, 3, and 6 months after the initiation of treatment. We also conducted an analysis to determine the proportion of patients achieving a PSA reduction of 50% or more (PSA50) and 90% or more (PSA90) as well as the percentage of patients with a notable decrease in PSA level to 0.2 ng/mL and PSA nadir of ≤0.02 ng/mL.

Results

Fifty-one patients were included in the study, with a median age of 73 years. At diagnosis of HSPC, the majority of patients had a Gleason score ≥8 (n=40, 78.40%) and a median baseline PSA level of 88 ng/mL. Approximately 45.1% (n=23) of patients had a Charlson Comorbidity Index over 1 and were receiving one or more nontumor-related treatments. The median follow-up time was 9.3 months (range, 1.16-15.8 months). The median reductions in PSA levels compared to baseline were 84.37%, 91.48%, 94.67% and 99.81% at 2 weeks, 1 month, 3 months and 6 months after administration of DARO with ADT, respectively. The median time to PSA50, PSA90, significant PSA reduction (PSA <0.2 ng/mL), and PSA nadir (PSA <0.02 ng/mL) was 0.97, 1.27, 1.98, and 2.08 months, respectively. AE mainly included fatigue (two patients) and arm pain (one patient), all of which were grade I or II AE. No grade III or AE were observed.

Conclusions

For treating prostate cancer, DARO with ADT has good early efficacy, demonstrating prompt and substantial control of PSA levels, with a favorable safety profile.

Predictors of poor response to first-generation anti-androgens as criteria for alternate treatments for patients with non-metastatic castration-resistant prostate cancer

PURPOSE

There are no criteria for administering first- or second-generation anti-androgens (FGA and SGA, respectively) to patients with non-metastatic castration-resistant prostate cancer (nmCRPC). This study aimed to assess the efficacy of alternative FGA therapy in nmCRPC patients and the prognosis of these patients and to identify factors for predicting patients potentially responsive to FGA.

METHODS

Data from 63 men with nmCRPC who underwent alternative FGA therapy (bicalutamide, flutamide, or chlormadinone acetate) as first-line therapy after failure of primary androgen-deprivation therapy (PADT) between 2004 and 2017 at Hiroshima University Hospital and affiliated hospitals were retrospectively investigated. The associations of clinicopathological parameters with overall survival (OS) and prostate-specific antigen (PSA) progression-free survival (PFS) of alternative FGA-treated patients were analyzed.

RESULTS

Time to CRPC [p = 0.007, hazard ratio (HR) = 4.77], regional lymph node involvement at the diagnosis of CRPC (p = 0.022, HR = 2.42), and PSA-PFS of alternative FGA therapy ≤ 6 months (p = 0.020, HR = 2.39) were identified as prognostic factors using a multivariate analysis. Additionally, Cox proportional hazard models revealed that PSA nadir value > 1 ng/mL during PADT (p = 0.034, HR = 2.40) and time from starting PADT to PSA nadir ≤ 1 year (p = 0.047, HR = 1.85) were predictive factors for worse PSA-PFS in alternative FGA therapy.

CONCLUSIONS

Shorter time to CRPC, regional lymph node involvement, PSA nadir during PADT > 1 ng/mL, and time from starting PADT to PSA nadir ≤ 1 year might suggest the potential benefit of immediate commencement of SGA, compared to FGA administration after nmCRPC diagnosis.

The Importance of Time to Prostate-Specific Antigen (PSA) Nadir after Primary Androgen Deprivation Therapy in Hormone-Naïve Prostate Cancer Patients

Prostate-specific antigen (PSA) is currently the most useful biomarker for detection of prostate cancer (PCa). The ability to measure serum PSA levels has affected all aspects of PCa management over the past two decades. The standard initial systemic therapy for advanced PCa is androgen-deprivation therapy (ADT). Although PCa patients with metastatic disease initially respond well to ADT, they often progress to castration-resistant prostate cancer (CRPC), which has a high mortality rate. We have demonstrated that time to PSA nadir (TTN) after primary ADT is an important early predictor of overall survival and progression-free survival for advanced PCa patients. In in vivo experiments, we demonstrated that the presence of fibroblasts in the PCa tumor microenvironment can prolong the period for serum PSA decline after ADT, and enhance the efficacy of ADT. Clarification of the mechanisms that affect TTN after ADT could be useful to guide selection of optimal PCa treatment strategies. In this review, we discuss recent in vitro and in vivo findings concerning the involvement of stromal–epithelial interactions in the biological mechanism of TTN after ADT to support the novel concept of “tumor regulating fibroblasts”.

Predictive factor of androgen deprivation therapy for patients with advanced stage prostate cancer

Background

The purpose of this study was to identify the predictive factors for the efficacy of androgen deprivation therapy (ADT) in men with hormone-sensitive prostate cancer (PC) with or without distant metastasis.

Methods

A retrospective review of PC patients was conducted of the medical records. We enrolled 246 patients who received primary ADT. PC patients treated with ADT for presumed nonlocalized PC were evaluated on the efficacy of ADT using prostate-specific antigen (PSA) time to progression (TTP) and compared factors associated with TTP in patients with distant metastasis and patients without distant metastasis.

Results

A total of 246 patients were treated primarily with ADT. The median follow-up period was 20.2 months. One hundred and ninety-one patients had metastatic disease. The median TTP on ADT for the distant metastasis group was 14.8 months versus 60.1 months in the without distant metastasis group (P < 0.0001). In the univariate analysis only, PSA nadir after ADT was associated with longer TTP (hazard ratio, 10.69; 95% confidence interval, 5.56–20.57). In the multivariate analysis, high grade tumor and PSA nadir were independent factors associated with a shorter TTP.

Conclusion

In this study of hormone-sensitive PC patients treated with ADT for nonlocalized PC, high grade tumor and PSA nadir were predicting factors of this treatment.