The development of risk groups in men with metastatic castration-resistant prostate cancer based on risk factors for PSA decline and survival

Bellmunt risk score as a survival predictor in patients with metastatic castration-resistant prostate cancer

BACKGROUND

The prognosis of metastatic castration-resistant prostate cancer (mCRPC) is influenced by numerous individual factors. Despite various proposed prognostic models, the clinical application of these remains limited, probably due to complexity. Our study aimed to evaluate the predictive value of the Bellmunt risk score, which is well-known for urothelial carcinoma and easily assessed, in mCRPC patients.

METHODS

The Bellmunt risk score was calculated from three risk factors (Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥1, serum hemoglobin <10 g/dL, presence of liver metastases) in 125 patients who received first-line mCRPC treatment between 2005 and 2023. In addition, a modified score was established (one point each for hemoglobin <10 g/dL and the presence of liver metastases added to the ECOG PS). Associations with overall survival (OS) under first- and second-line therapy were tested using Cox regression analyzes, log-rank tests, concordance index (C-index) and time-dependent receiver operating characteristic.

RESULTS

There is a significant correlation between the level of the Bellmunt risk score and shorter OS (hazard ratio: 3.23, 95% confidence interval: 2.06-5.05; log-rank p < 0.001; C-index: 0.724). The semi-quantitative modified risk score showed even better prognostic discrimination (log-rank p < 0.001, C-index: 0.764). The score and its dynamics were also predictive in the second-line setting (log-rank p < 0.001 and = 0.01; C-index: 0.742 and 0.595).

CONCLUSIONS

The Bellmunt risk score is easy to assess and provides useful prognostic information in mCRPC, and can support physicians in their treatment decisions.

Flare phenomenon visualized by 99mTc-bone scintigraphy has prognostic value for patients with metastatic castration-resistant prostate cancer

OBJECTIVE

This study aimed to determine the prognostic value of the flare phenomenon in patients with metastatic castration-resistant prostate cancer (mCRPC) using the bone scan index (BSI) derived from 99mTc-methylenediphosphonate (MDP) bone scintigraphy images.

METHODS

We categorized 72 patients from the PROSTAT-BSI registry with mCRPC who were followed-up for 2 years after starting docetaxel chemotherapy to groups based on pre-chemotherapy BSI values of < 1, 1-4, and > 4. We assessed the effects of the flare phenomenon (defined as a > 10% increase in the BSI within 3 months of starting chemotherapy, followed by > 10% improvement within the next 3 months) on survival using Kaplan-Meier curves and Cox proportional hazard analyses.

RESULTS

The flare phenomenon was found in 26 (36%) of the 72 patients. Prostate-specific antigen (PSA), alkaline phosphatase (ALP), and hemoglobin (Hb) levels steadily increased, then deteriorated in patients with and without flare, respectively. Elevated BSI and PSA values at 3 months after starting therapy and the absence of abiraterone or/and enzalutamide therapy led to poor 2-year overall survival (OS) in the group without flare. In contrast, no influence was noticeable in the group with flare. The results of multivariable analyses that included only factors associated with PSA and BSI showed that increased baseline BSI (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.04-1.86; P = 0.023) and PSA (HR, 7.15; 95% CI 2.13-24.04; P = 0.0015) values could be independent risk factors for patients with mCRPC without flare. However, these factors lost significance during flare. The risk for all-cause death was significantly higher among patients with BSI > 4 without, than with flare. The results of univariable analyses indicated that flare positively impacted survival (HR, 0.24; 95% CI 0.06‒0.91; P = 0.035). Multivariable analysis did not identify any factors that could predict outcomes.

CONCLUSION

Favorable prognosis, with fewer disturbances from other factors such as the use of abiraterone or/and enzalutamide, PSA changes, and BSI, was attainable in cases when the mCRPC patient demonstrated flare phenomenon. Follow-up bone scintigraphy at least every 3 months could help to determine the prognosis of patients with bone metastasis of mCRPC.

Abiraterone and enzalutamide in the first line therapy of metastatic castration resistant prostate cancer

Background

The aim was to assess therapeutic outcomes and tolerance in patients with metastatic castration resistant prostate cancer (mCRPC) treated with androgen receptor targeted agents (ARTA) treatment at one oncological center in the Czech Republic.

Materials and methods

Retrospective analysis of 64 patients with mCRPC treated with abiraterone (50 patients) and enzalutamide (14 patients) in the first line of this disease was conducted. Kaplan-Meier analysis was used to calculate progression free survival (PFS) and overall survival (OS). We performed a multivariate analysis of risk factors for treatment outcomes (PFS, OS) by Cox regression analysis.

Results

The median follow-up was 28.4 months. The median PFS was 15.4 months [95% confidence interval (CI): 12.3-18.5], median OS was 38.2 months (95% CI: 19.9-56.5). Regression analysis demonstrated a favorable prognostic effect on PFS in patients with reduction of PSA ≥ 50 %, in patients with early reduction of prostate-specific antigen (PSA) ≥ 50% within 3 months, in patients younger than 74 years and in overall performance status (PS) 0. Regression analysis demonstrated a favorable prognostic effect on OS in patients with reduction of PSA ≥ 50 %, in patients with early reduction of PSA ≥ 50 % within 3 months and in patients with overall PS 0. Adverse effects grade 3-4 were reported in 17 (27.9%) patients in abirateron arm and in 1 (7.1%) patient in enzalutamide arm.

Conclusion

The analysis of patients with mCRPC treated with ARTA in the first line showed that ARTA represents an effective and safe therapy and contributes to longer survival.

The Detection and Negative Reversion of Circulating Tumor Cells as Prognostic Biomarkers for Metastatic Castration-Resistant Prostate Cancer with Bone Metastases Treated by Enzalutamide

Enzalutamide is a second-generation androgen receptor inhibitor that increases overall survival (OS) rates in patients with metastatic castration-resistant prostate cancer (mCRPC). This study evaluates the efficacy of circulating tumor cell (CTC) status as a prognostic biomarker following enzalutamide administration. A retrospective subgroup analysis and prognostic survey were conducted on 43 patients with mCRPC and bone metastases treated in Juntendo University-affiliated hospitals from 2015 to 2022. Patients were treated with 160 mg enzalutamide daily. CTC analyses on blood samples were performed regularly before and every three months after treatment. The relationship between the patients' clinical factors and the OS rate was analyzed using the log-rank test; the median OS was 37 months. Patients with no detected CTCs at baseline showed significantly longer OS than those with detectable CTCs at baseline. Furthermore, patients demonstrating negative reversion of CTCs during enzalutamide treatment had significantly longer OS than patients with CTC-positivity. Two biomarkers-higher hemoglobin at baseline and achieving negative reversion of CTCs-were significantly associated with prolonged OS. This study suggests that patients achieving CTC-negative reversion during treatment for mCRPC with bone metastases exhibit improved long-term OS. Chronological measurement of CTC status might be clinically useful in the treatment of mCRPC.

Effectiveness and safety of radium-223 dichloride in patients with castration-resistant prostate cancer and bone metastases in real-world practice: A multi-institutional study

OBJECTIVE

Radium-223 (Ra-223) dichloride is the bone-targeted radioligand therapy that prolongs overall survival (OS) in patients with bone-metastatic castration-resistant prostate cancer (CRPC). We aimed to evaluate the safety and effectiveness of this treatment in real-world practice.

METHODS

We included Japanese men treated with Ra-223 for bone-metastatic CRPC from 10 institutions, retrospectively. Primary endpoint was OS. Secondary endpoint was maximum decline of alkaline phosphatase (ALP), lactate dehydrogenase, and prostate-specific antigen values, the rate of adverse events, and time to pathological fracture after Ra-223 treatment. Exploratory endpoint was the associations between clinical parameters and OS.

RESULTS

In total, 73 men with bone metastatic CRPC treated with Ra-223 were enrolled. The median OS was 20.9 months. ALP levels decreased significantly from pre-treatment (p = 0.03). Anemia occurred in three (4.1%) patients. Grade ≥ 3 non-pathological fractures occurred in four (5.5%) men. Nine (12.3%) patients presented pathological fracture; 7/30 (23.3%) were in men without concomitant use of a bone-modifying agent (BMA) while 2/43 (4.7%) were in patients with concomitant BMA (p = 0.03). The median OS in patients with ≥3 cycles treatment (27.2 months, p < 0.001) or hemoglobin ≥12 g/dl (27.2 months, p = 0.001) or absence of bone pain (36.3 months, p = 0.004) was significantly longer compared to those who with ≤2 cycles or hemoglobin<12 g/dl or presence of bone paint, respectively.

CONCLUSIONS

This study has shown the outcomes of Ra-223 treatment in real-world practice, where the number of treatment cycles, baseline anemia and bone pain may be useful to predict OS in Ra-223 treatment.

Combined Longitudinal Clinical and Autopsy Phenomic Assessment in Lethal Metastatic Prostate Cancer: Recommendations for Advancing Precision Medicine

BACKGROUND

Systematic identification of data essential for outcome prediction in metastatic prostate cancer (mPC) would accelerate development of precision oncology.

OBJECTIVE

To identify novel phenotypes and features associated with mPC outcome, and to identify biomarker and data requirements to be tested in future precision oncology trials.

DESIGN SETTING AND PARTICIPANTS

We analyzed deep longitudinal clinical, neuroendocrine expression, and autopsy data of 33 men who died from mPC between 1995 and 2004 (PELICAN33), and related findings to mPC biomarkers reported in the literature.

INTERVENTION

Thirty-three men prospectively consented to participate in an integrated clinical-molecular rapid autopsy study of mPC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Data exploration with correction for multiple testing and survival analysis from the time of diagnosis to time to death and time to first occurrence of severe pain as outcomes were carried out. The effect of seven complications on the modeled probability of dying within 2 yr after presenting with the complication was evaluated using logistic regression.

RESULTS AND LIMITATIONS

Feature exploration revealed novel phenotypes related to mPC outcome. Four complications (pleural effusion, severe anemia, severe or controlled pain, and bone fracture) predict the likelihood of death within 2 yr. Men with Gleason grade group 5 cancers developed severe pain sooner than those with lower-grade tumors. Surprisingly, neuroendocrine (NE) differentiation was frequently observed in the setting of high serum prostate-specific antigen (PSA) levels (≥30 ng/ml). In 4/33 patients, no controlled (requiring analgesics) or severe pain was detected, and strikingly, 14/15 metastatic sites studied in these men did not express NE markers, suggesting an inverse relationship between NE differentiation and pain in mPC. Intracranial subdural metastasis is common (36%) and is usually clinically undetected. Categorization of "skeletal-related events" complications used in recent studies likely obscures the understanding of spinal cord compression and fracture. Early death from prostate cancer was identified in a subgroup of men with a low longitudinal PSA bandwidth. Cachexia is common (body mass index <0.89 in 24/31 patients) but limited to the last year of life. Biomarker review identified 30 categories of mPC biomarkers in need of winnowing in future trials. All findings require validation in larger cohorts, preferably alongside data from this study.

CONCLUSIONS

The study identified novel outcome subgroups for future validation and provides "vision for mPC precision oncology 2020-2050" draft recommendations for future data collection and biomarker studies.

PATIENT SUMMARY

To better understand variation in metastatic prostate cancer behavior, we assembled and analyzed longitudinal clinical and autopsy records in 33 men. We identified novel outcomes, phenotypes, and aspects of disease burden to be tested and refined in future trials.

Prognostic role of platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio in patients with metastatic castration resistant prostate cancer treated with Abiraterone or Enzalutamide

BACKGROUND

Platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) are markers of systemic inflammation associated with poor outcome in several solid tumours. We retrospectively investigated the prognostic role of PLR and, secondly, NLR in mCRPC patients treated with Abiraterone Acetate (AA) or Enzalutamide (E), both in pre- and post-docetaxel setting.

MATERIALS AND METHODS

225 mCRPC patients treated with AA or E with basal blood count were divided in three groups according to PLR (PLR1 <128; PLR2 128-190; PLR >190) and in two groups according to NLR (<3 vs ≥3). Outcome measures were progression-free survival (PFS) and overall-survival (OS). Univariate and multivariate analyses were performed.

RESULTS

110 patients were in PLR1, 58 in PLR2 and 57 in PLR3. Median OS was 22.0, 20.6 and 21.2 months in PLR1, PLR2 and PLR3 (PLR2 vs PLR1: HR 0.97, 95%CI 0.62-1.52, p=0.90; PLR3 vs PLR1: HR 1.37, 95%CI 0.90-2.08, p=0.14). Median PFS was 9.2, 12.7 and 8.5 months in PLR1, PLR2 and PLR3 (PLR2 vs PLR1: HR 0.87, 95%CI 0.59-1.27, p=0.47; PLR3 vs PLR1: HR 1.15, 95%CI 0.80-1.66, p=0.45). 142 patients were in NLR<3 and 83 in NLR≥3. Median OS was 26.5 months in NLR<3 and 17.0 months in NLR≥3 (HR 1.75, 95%CI 1.22-2.51, p=0.02). Median PFS was 10.1 months in NLR<3 and 7.6 months in NLR≥3 (HR 1.37, 95%CI 1.00-1.88, p=0.05).

CONCLUSIONS

In this retrospective analysis of mCRPC patients treated with AA or E we did not identify a prognostic role of baseline PLR, while we found a significant prognostic role of baseline NLR.

PSA Kinetics as Prognostic Markers of Overall Survival in Patients with Metastatic Castration-Resistant Prostate Cancer Treated with Abiraterone Acetate

Background

Abiraterone acetate (AA) is widely used in the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC). However, a significant percentage of patients will still progress, highlighting the need to identify patients more likely to benefit from AA. Parameters linked to prostate-specific antigen (PSA) kinetics are promising prognostic markers. We have examined clinical and PSA-related factors potentially associated with overall survival (OS) in patients treated with AA.

Methods

Between 2011 and 2014, 104 patients with mCRPC treated with AA after progression to docetaxel at centers of the Catalan Institute of Oncology were included in this retrospective study. Patients were assessed monthly. Baseline characteristics and variables related to PSA kinetics were included in univariate and multivariate analyses of OS.

Results

Median OS was 16.4 months (range 12.4-20.6) for all patients. The univariate analysis identified the following baseline characteristics as significantly associated with OS: ECOG PS, location of metastases, time between starting androgen deprivation therapy and starting AA, time between stopping docetaxel treatment and starting AA, neutrophil-lymphocyte ratio (NLR), alkaline phosphatase levels, and PSA levels. Factors related to PSA kinetics associated with longer OS were PSA response >50%, early PSA response (>30% decline at four weeks), PSA decline >50% at week 12, PSA nadir <2.4ng/mL, time to PSA nadir >140 days, the combination of PSA nadir and time to PSA nadir, and low end-of-treatment PSA levels. The multivariate analysis identified ECOG PS (HR 37.46; p<0.001), NLR (HR 3.7; p<0.001), early PSA response (HR 1.22; p=0.002), and time to PSA nadir (HR 0.39; p=0.002) as independent prognostic markers.

Conclusion

Our results indicate an association between PSA kinetics, especially early PSA response, and outcome to AA after progression to docetaxel. Taken together with other factors, lack of an early PSA response could identify patients who are unlikely to benefit from AA and who could be closely monitored with a view to offering alternative therapies.

Survival outcomes of low prostate-specific antigen levels and T stages in patients with high-grade prostate cancer: a population-matched study

Objective: To evaluate the prostate cancer-specific survival (PCSS) of low T stages or low prostate-specific antigens (PSA) levels in men with high-grade prostate cancer.

Materials and Methods: Patients with non-metastatic prostate cancer (T1-4N0M0) and Gleason score 8-10 in the Surveillance, Epidemiology, and End Results database from 2004-2010 were identified. These men were stratified by T stages (T1, T2, T3a, T3b-4) and PSA levels (<4.0 ng/ml, 4.0-10.0 ng/ml, 10.1-20.0 ng/ml, >20.0 ng/ml). Propensity-score matching (PSM) was conducted to balance the covariates. Kaplan-Meier analysis and multivariable Cox regressions were performed to analyze the PCSS in different T stage or PSA levels groups.

Results: A total of 33231 patients aging 69(62~76) years were identified. The overall cohort results showed that the PCSS of T1 group was significantly worse than that of T2 and T3a groups [T2 HR: 0.62(0.57~0.67); T3 HR: 0.70(0.63~0.77)]. There were no significant difference between T2 and T3a groups [T2 HR: 0.98 (0.91~1.05)]. The PSA <4.0 ng/ml group had significantly worse PCSS than PSA 4.0-10.0 ng/ml [PSA 4.0-10.0 ng/ml HR: 0.77(0.68~0.88)]. PSM methods were implemented in the comparison of T1 vs T2, T1 vs T3a, T2 vs T3a. and PSA< 4.0 ng/ml vs PSA 4.0-10.0 ng/ml, The results in these matched cohorts showed that T1 group was associated with significantly worse PCSS than T2 group [T1 HR: 1.31(1.20~1.44)] and T3a group [T1 HR: 1.33(1.16~1.52)]. There were no significant differences between T2 and T3a groups [T3a HR: 1.14(0.99~1.32)]. The PCSS of patients with PSA< 4.0 ng/ml was significantly worse that these with PSA 4.0-10.0 ng/ml in the matched cohort [PSA< 4.0 ng/ml HR: 1.3(1.08~1.56)].

Conclusions: For patients with high-grade PCa, the PCSS of patients seems to be worse in the T1 stage than those in T2 and T3a stages. Patients with PSA <4.0 ng/ml appears to have poorer prognosis than those with PSA 4.0-10.0 ng/ml.

Five-year Survival Prediction and Safety Outcomes with Enzalutamide in Men with Chemotherapy-naïve Metastatic Castration-resistant Prostate Cancer from the PREVAIL Trial

BACKGROUND

In the PREVAIL study, enzalutamide significantly improved clinical outcomes versus placebo in patients with chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC).

OBJECTIVE

To evaluate long-term benefits and risks of enzalutamide in the final prespecified PREVAIL analysis.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a final 5-yr survival analysis of PREVAIL in men with chemotherapy-naïve mCRPC from the enzalutamide (n = 689) and placebo (n = 693) arms.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Predictors of the primary outcome of overall survival were estimated using the Kaplan-Meier method. Long-term adverse events over time were analyzed.

RESULTS AND LIMITATIONS

At the 5-yr data cutoff, 1382 of 1717 (80%) men had died. Enzalutamide reduced the hazard of death by 17% (hazard ratio 0.83; 95% confidence interval [CI] 0.75-0.93; p < 0.001), despite 65%, 54%, and 43% of placebo-treated patients receiving subsequent docetaxel, abiraterone, and enzalutamide, respectively. Median overall survival was 36 mo (95% CI 34-38) in the enzalutamide arm versus 31 mo (95% CI 29-34) in the placebo arm, with a median follow-up of 69 mo. Prognostic modeling showed 5-yr survival rates of 42%, 24%, and 5% for low-, intermediate-, and high-risk groups, respectively. Greater degrees of confirmed prostate-specific antigen declines (≤3 mo) were associated with greater 5-yr survival. A higher incidence of fatal treatment-emergent adverse events was observed with enzalutamide (6.9% vs 3.8%), with an increase in fatal cardiovascular events (1.6% vs 0.4%).

CONCLUSIONS

With >5 yr of follow-up, enzalutamide continued to demonstrate improved survival in patients with mCRPC despite crossover and multiple subsequent effective therapies, balanced against a slightly higher rate of fatal cardiovascular events. PREVAIL is registered on ClinicalTrials.gov as NCT01212991.

PATIENT SUMMARY

We report a maintained long-term survival benefit with enzalutamide and risks with >5 yr of enzalutamide treatment and follow-up in men with metastatic prostate cancer, and identify groups of men with widely different outcomes based on clinical factors.

Reduced cancer-specific survival of low prostate-specific antigen in high-grade prostate cancer: A population-based retrospective cohort study

OBJECTIVE

The aim of this study was to evaluate the survival outcomes of different prostate-specific antigens (PSA) levels in men with high-grade prostate cancer.

MATERIALS AND METHODS

From 2004 to 2015 in the Surveillance, Epidemiology, and End Results database, men diagnosed with clinically localized prostate cancer and a Gleason score (GS) 8-10 were identified. Patients were divided into the PSA levels <4.0 ng/ml, 4.0-10.0 ng/ml, 10.1-20.0 ng/ml, and >20.0 ng/ml groups. Multivariable Cox regressions and Kaplan-Meier analysis were adopted to analyze the prostate cancer-specific survival (PCSS).

RESULTS

59,336 men with a median age of 70 (63-76) years with a GS 8-10 were included. The PCSS of patients with a PSA <4.0 ng/ml was significantly worse than that of patients with a PSA 4.0-10.0 ng/ml [hazard ratio (HR): 1.43 (1.28-1.58)], but was better than that of patients with a PSA 10.1-20.0 ng/ml [HR: 1.18 (1.06-1.31)]. After stratifying patients by GS, the differences between patients with a PSA <4.0 ng/ml and a PSA 4.0-10.0 ng/ml were only significant in those with a GS 9 and 10 [GS 9 HR: 1.49 (1.28-1.72); GS 10 HR: 1.42 (1.12-1.8)], but not in those with a GS 8 [HR: 1.04 (0.95-1.14)]. Moreover, the PCSS of patients with a PSA <4.0 ng/ml and a PSA 10.0-20.0 ng/ml were similar in patients with GS 9 and 10 diseases [GS 9: HR: 1.06 (0.91-1.23); GS 10: HR: 1.13 (0.89-1.44)].

CONCLUSIONS

Patients with a PSA <4.0 ng/ml had poorer PCSS than patients with a PSA 4.0-10.0 ng/ml. Similar PCSS was found in patients whose PSA levels were 10.1-20.0 ng/ml in patients with GS 9-10 prostate cancer.

Circulating miR-141 and miR-375 are associated with treatment outcome in metastatic castration resistant prostate cancer

Metastatic castration resistant prostate cancer (mCRPC) is associated with high mortality, where monitoring of disease activity is still a major clinical challenge. The role of microRNAs (miRs) has been widely investigated in prostate cancer with both diagnostic and prognostic potential. The aim of this study was to investigate the relationship between circulating miRs and treatment outcome in mCRPC patients. The relative expression of five miRs (miR-93-5p, -125b-1-5p, -141-3p, -221-3p, and miR-375-3p) was investigated in plasma samples from 84 mCRPC patients; 40 patients were treated with docetaxel (DOC cohort) and 44 patients with abiraterone (ABI cohort). Blood was sampled at baseline before treatment start and at radiological progression. The plasma levels of four miRs; miR-93-5p, -141-3p, -221-3p, and miR-375-3p decreased significantly after treatment initiation in patients receiving docetaxel, and for miR-141-3p and miR-375-3p the level increased again at the time of radiological progression. In the patients treated with abiraterone, the plasma level of miR-221-3p likewise decreased significantly after the first treatment cycle. High baseline levels of both miR-141-3p and miR-375-3p were significantly associated with a shorter time to radiological progression in both cohorts. Additionally, high baseline levels of miR-141-3p and miR-221-3p were significantly associated with a shorter overall survival (OS) in the ABI cohort, while high levels of miR-141-3p and miR-375-3p were significantly associated with shorter OS in the DOC cohort. Plasma levels of miR-141-3p and miR-375-3p may predict time to progression in mCRPC patients treated with docetaxel or abiraterone. The clinical impact of these findings is dependent on validation in larger cohorts.

Development of a prognostic model for survival time prediction in castration-resistant prostate cancer patients

BACKGROUND

To identify predictors of survival in patients treated with docetaxel chemotherapy for castration-resistant prostate cancer (CRPC).

METHODS

We retrospectively analyzed clinical data from 186 patients who underwent docetaxel chemotherapy for CRPC from 2005 to 2016 at a single center. Pretreatment baseline variables including demographic and clinicopathological data were reviewed. Disease progression was defined by imaging and/or consecutive prostate-specific antigen (PSA) elevation. The systemic immune-inflammation index (SII), the modified Glasgow Prognostic Score (mGPS), and the neutrophil-lymphocyte ratio (NLR) were calculated. Univariable and multivariable Cox proportional hazards regression analyses reporting hazard ratios assessed the risk for disease progression and overall survival (OS). A survival nomogram was constructed.

RESULTS

Most patients (n = 139, 74.7%) completed at least 6 cycles of docetaxel chemotherapy. 156 patients (82.9%) experienced disease progression during the studied period. Only mGPS was independently associated with disease progression in a multivariable model (P < 0.01). During the studied period, 98 patients (52.1%) died. The built survival nomogram included statistically significant variables for OS in univariable analysis: hemoglobin, PSA, alkaline phosphatase (AP), lactate dehydrogenase, SII, neutrophil-lymphocyte ratio, mGPS, and site of metastases; and had a concordance index of 0.703. At decision curve analysis, the nomogram led to superior outcomes for any decision associated with a threshold probability of above 40%. In multivariable analysis, only AP (P = 0.02), hemoglobin and PSA (P < 0.01, respectively) remained associated with OS.

CONCLUSIONS

PSA, AP, and hemoglobin are independent prognosticators for OS. Although mGPS is a promising marker for tumor progression and SII is a plausible prognostic marker for OS, valid integration of inflammatory indices into a prognostic model requires validation studies. Predictive and prognostic biomarkers are desperately needed to guide physicians in treatment counseling given the heterogeneous nature of CRPC and the plethora of effective therapies.

Development and validation of a prognostic model for overall survival in chemotherapy-naïve men with metastatic castration-resistant prostate cancer

Background

Prognostic models are needed that reflect contemporary practice for men with metastatic castration-resistant prostate cancer (mCRPC). We sought to identify predictive and prognostic variables for overall survival (OS) in chemotherapy-naïve men with mCRPC treated with enzalutamide.

Patients and methods

Patients from the PREVAIL trial database (enzalutamide versus placebo) were randomly split 2 : 1 into training (n = 1159) and testing (n = 550) sets. Using the training set, 23 predefined variables were analyzed and a multivariable model predicting OS was developed and validated in an independent testing set.

Results

Patient characteristics and outcomes were well balanced between training and testing sets; median OS was 32.7 months in each. The final validated multivariable model included 11 independent prognostic variables. Median OS for low-, intermediate-, and high-risk groups (testing set) defined by prognostic risk tertiles were not yet reached (NYR) (95% CI NYR-NYR), 34.2 months (31.5-NYR), and 21.1 months (17.5-25.0), respectively. Hazard ratios (95% CI) for OS in the low- and intermediate-risk groups versus high-risk group were 0.20 (0.14-0.29) and 0.40 (0.30-0.53), respectively. Secondary outcomes of response and progression differed widely in model-defined risk groups. Enzalutamide improved outcomes in all prognostic risk groups.

Conclusions

Our validated prognostic model incorporates variables routinely collected in chemotherapy-naïve men with mCRPC treated with enzalutamide, identifying subsets of patients with widely differing survival outcomes that provide useful information for external validation, patient care, and clinical trial design.

Trial registration

ClinicalTrials.gov: NCT01212991.

Phase 1b trial of docetaxel, prednisone, and pazopanib in men with metastatic castration-resistant prostate cancer

BACKGROUND

Docetaxel prednisone is a standard of care for men with metastatic castration-resistant prostate cancer (mCRPC), and plasma vascular endothelial growth factor (VEGF) levels are a poor prognostic factor in this population; therefore, we evaluated the combination of docetaxel prednisone with pazopanib, an oral VEGF receptor inhibitor, for safety and preliminary efficacy.

METHODS

This is a two-site phase 1b Department of Defense Prostate Cancer Clinical Trials Consortium trial of docetaxel, prednisone, and pazopanib once daily and ongoing androgen deprivation therapy and prophylactic pegfilgrastim in men with mCRPC. The primary endpoint was safety and the determination of a maximum tolerated dose (MTD) through a dose-escalation and expansion design; secondary endpoints included progression-free and overall survival (OS), prostate specific antigen (PSA) declines, radiographic responses, and pharmacokinetic and plasma angiokine biomarker analyses.

RESULTS

Twenty-five men were treated over six dose levels. Pegfilgrastim was added to the regimen after myelosuppression limited dose escalation. With pegfilgrastim, our target MTD of docetaxel 75 mg/m² q3 weeks; prednisone 10 mg daily; and pazopanib 800 mg daily was reached. Eleven additional patients were accrued at this dose level for a total of 36 patients. Dose-limiting toxicities included neutropenia, syncope, and hypertension. Three deaths attributed to study treatment occurred. The objective response rate was 31%; median PFS was 14.1 months (95% confidence interval [CI]: 7.1 and 22.2); and OS was 18.6 months (95% CI: 11.8 and 22.2).

CONCLUSIONS

The combination of docetaxel, prednisone, and pazopanib (with pegfilgrastim) was tolerable at full doses and demonstrated promising efficacy in a relatively poor risk patients with mCRPC. Further development of predictive biomarkers may enrich for patients who receive clinical benefit from this regimen.

The Pretherapeutic Neutrophil-to-Lymphocyte Ratio for Docetaxel-Based Chemotherapy Is Useful for Predicting the Prognosis of Japanese Patients with Castration-Resistant Prostate Cancer

Introduction and Objectives

The neutrophil-to-lymphocyte ratio (NLR) has been suggested as a simple marker of the systemic inflammatory response in critical care patients. The NLR can be easily calculated from routine complete blood counts in the peripheral blood. This parameter has been reported to be an independent prognosticator for some solid malignancies. In the present study, we examined the importance of the NLR as a prognostic marker for castration-resistant prostate cancer (CRPC) patients who received docetaxel- (DOC-) based chemotherapy.

Methods

We analyzed a total of 73 patients who received DOC chemotherapy for CRPC in Yokohama City University Medical Center and affiliated hospitals. Complete blood cell counts were performed, and the NLR was calculated using the neutrophil and lymphocyte counts obtained on the same day or a few days before the initiation of DOC chemotherapy. We determined the NLR cutoff value based on the sensitivity and specificity levels derived from area under the receiver operator characteristic curves for death.

Results

The median overall survival (OS) after DOC was 21.0 months (range: 2.0–51.0). The median OS was shorter in patients with a high NLR (≥2.59) than in those with a low NLR (<2.59) (12.0 versus 31.6 months, p=0.001). In the multivariate analysis, the NLR and lymph node (LN) metastasis were independent predictors of the OS (hazard ratio 3.643, p=0.001; hazard ratio 2.184, p=0.038, respectively).

Conclusions

The higher NLR group showed a significantly poorer OS than the lower NLR group. Pre-DOC NLR might be a new marker for predicting the prognosis of patients who receive DOC chemotherapy.

The Potential for Chemotherapy-Free Strategies in Advanced Prostate Cancer

The treatment landscape for advanced prostate cancer is evolving rapidly, with new agents and strategies, and more optimal use of existing therapies under constant development. Efforts were focused on better understanding of the biology of the disease. This effort has paved the way for a more contemporary and effective therapies to be developed. There are now 6 FDA-approved therapies that increase overall survival. These include the immunotherapy sipuleucel-T; the 2 androgen pathway inhibitors: abiraterone acetate and enzalutamide; 2 chemotherapy drugs: docetaxel and cabazitaxel; and the radionuclide: radium-223. Advanced prostate cancer may be one of the few cancers for which multiple chemotherapy and nonchemotherapy regimens are considered as standard. Several recently published clinical trials have demonstrated the suprising activity of chemotherapy-free strategies, and we should not be too eager to discount these "old-fashioned" treatments. Optimal sequencing is still unclear because new therapies have proliferated so quickly that comparative data are limited. In this short communication, we identify current challenges and unmet needs in advanced prostate cancer and provide an overview of their respective clinical activity, while highlighting distinctions between therapies.

Three-year interim results of overall and progression-free survival in a cohort of patients with prostate cancer (GESCAP group)

AIMS

To describe the 3-year progression-free survival (PFS), overall survival (OS) and disease-specific mortality in the prospective prostate cancer GESCAP cohort, as well as the progression to castration resistance in patients on hormone therapy.

MATERIAL AND METHODS

Prospective, observational, epidemiological, multicentre study. Of the 4087 patients recruited, 3843 were evaluable. The variables analysed were the risk group (localized, locally advanced, lymph involvement, metastatic), age, prostate-specific antigen (PSA) levels, Gleason score and initial treatment. Kaplan Meier survival analysis, the log-rank test and the Cox model were used to evaluate the survival data.

RESULTS

Three-year PFS was 81.4% and OS was 92.4%. During the 3 years of follow-up, 303 patients died (7.9%), 110 of them (36.3%) due to disease-related causes. The probability of castration resistance for all patients on hormone therapy (n=715) was 14.2%: 5%, 9.9%, 26.1% and 44.4% in localized, locally advanced, lymph involvement and metastatic cancer, respectively (log-rank P<.0001). Patients with metastases had poorer outcomes with respect to PFS, OS, disease-specific mortality and castration resistance. In the multivariate analysis, the Gleason score, PSA and presence of metastases were associated with shorter OS and PFS.

CONCLUSIONS

Our study showed stratification of risk, with a more unfavourable prognosis for patients with metastases. Patients with locally advanced disease differed with respect to those with localized disease due to their higher risk as regards disease-specific mortality. (Controlled-trials.com ISRCTN19893319).

Prognostic models for predicting overall survival in metastatic castration-resistant prostate cancer: a systematic review

PURPOSE

Prognostic models are developed to estimate the probability of the occurrence of future outcomes incorporating multiple variables. We aimed to identify and summarize existing multivariable prognostic models developed for predicting overall survival in patients with metastatic castration-resistant prostate cancer (mCRPC).

METHODS

The protocol was prospectively registered (CRD42017064448). We systematically searched Medline and reference lists up to May 2018 and included experimental and observational studies, which developed and/or internally validated prognostic models for mCRPC patients and were further externally validated or updated. The outcome of interest was overall survival. Two authors independently performed literature screening and quality assessment.

RESULTS

We included 12 studies that developed models including 8750 patients aged 42-95 years. Models included 4-11 predictor variables, mostly hemoglobin, baseline PSA, alkaline phosphatase, performance status, and lactate dehydrogenase. Very few incorporated Gleason score. Two models included predictors related to docetaxel and mitoxantrone treatments. Model performance after internal validation showed similar discrimination power ranging from 0.62 to 0.73. Overall survival models were mainly constructed as nomograms or risk groups/score. Two models obtained an overall judgment of low risk of bias.

CONCLUSIONS

Most models were not suitable for clinical use due to methodological shortcomings and lack of external validation. Further external validation and/or model updating is required to increase prognostic accuracy and clinical applicability prior to their incorporation in clinical practice as a useful tool in patient management.

Prognostic and predictive clinical factors in patients with metastatic castration-resistant prostate cancer treated with cabazitaxel

INTRODUCTION

Cabazitaxel is one of several treatment options available for patients with metastatic castration-resistant prostate cancer who have progressed on docetaxel. Little is known about clinical factors that influence prognosis or treatment response for patients receiving cabazitaxel. Identifying prognostic and predictive factors could contribute to the optimal selection of patients for treatment after docetaxel.

METHODS

A retrospective review of patients enrolled on the cabazitaxel Canadian Early Access Program (C-EAP) was performed. Clinical factors were analyzed by univariable and multivariable Cox proportional hazards and logistic regression analysis to identify independent predictors of prognosis and response.

RESULTS

Forty-five patients from five centres in Canada were included in this study. On multivariable analysis, lower hemoglobin was associated with shorter survival. No other factors were independently associated with survival, prostate-specific antigen (PSA) response, or primary PSA progression.

CONCLUSIONS

Clinical factors predicting survival or treatment response were not identified for men with castration-resistant prostate cancer receiving cabazitaxel. Larger studies may be necessary to identify clinical factors and biomarkers that identify whether patients should or should not receive cabazitaxel.

The Influence of Prednisone on the Efficacy of Cabazitaxel in Men with Metastatic Castration-Resistant Prostate Cancer

Background: Cabazitaxel is a second-generation taxane that is approved for use with concomitant low dose daily prednisone in metastatic castration resistant prostate cancer (mCRPC) after docetaxel failure. Since the role of daily corticosteroids in improving cabazitaxel efficacy or ameliorating its safety profile has not been adequately investigated so far, we compared outcomes of patients receiving cabazitaxel with or without daily corticosteroids in a retrospective single-Institution cohort of mCRPC patients.

Patients and methods: Medical records of deceased patients with documented mCRPC treated with cabazitaxel following prior docetaxel between January, 2011 and January, 2017 were reviewed at the single participating center. Patients who were receiving daily doses of systemic corticosteroids other than low dose daily prednisone or prednisolone (<= 10 mg a day) were excluded. The primary end point of this analysis was overall survival (OS). Secondary end-points were exposure to cabazitaxel as well as incidence of grade 3-4 adverse events. Univariable and multivariable Cox proportional hazards regression was used to evaluate prednisone use and other variables as potentially prognostic for overall survival.

Results: Overall, among 91 patients, 57 patients received cabazitaxel concurrently with low dose prednisone and 34 patients did not receive concurrent prednisone. The median overall survival of the population was 9.8 months (interquartile range, 9 to 14). Patients receiving prednisone had an overall survival of 9 months (interquartile range, 8 to 12) vs.14 months (interquartile range, 9.4 to 16.7) for patients not treated with prednisone. Approximately 45% of patients had a >30% PSA decline at 12 weeks. Prednisone use was not significantly prognostic for overall survival or PSA decline ≥30% rates on regression analyses. Importantly, a >30% PSA decline at 12, but not at 3, 6, 9 weeks, was prognostic for improved survival at multivariate analysis

Conclusions: The data presented here support the hypothesis that omitting daily corticosteroids in cabazitaxel-treated patients has no negative impact on either survival or safety profile. In the large prospective trial CABACARE, cabazitaxel-treated patients will be randomized to receive or not receive daily prednisone. The CABACARE (EudraCT n. 2016-003646-81) study is currently ongoing at University Federico II of Naples and at other multiple participating centers in Italy.

Phase II study of radium-223 dichloride in Japanese patients with symptomatic castration-resistant prostate cancer

Background

Radium-223 dichloride (radium-223) is the first targeted alpha therapy approved for the treatment of castration-resistant prostate cancer (CRPC) with bone metastases. This study investigated the efficacy and safety of radium-223 in Japanese patients with symptomatic CRPC and bone metastases.

Methods

In this open-label, multicenter, phase II study, patients with progressive, symptomatic CRPC and bone metastases were treated with radium-223 (55 kBq/kg, intravenously) in a 4-week cycle for six cycles. The primary endpoint was the percent change in total alkaline phosphatase (ALP) from baseline at 12 weeks. Secondary endpoints included the percent ALP change from baseline to end of treatment (EOT), ALP response rates, percent change in prostate-specific antigen (PSA) from baseline to 12 weeks and EOT, PSA response rates, overall survival (OS), and time to symptomatic skeletal events (SSEs). Adverse events were monitored throughout the study period.

Results

Of the 49 Japanese patients (median age 74 years), 28 completed all infusions. Mean percent change in total ALP and PSA from baseline to 12 weeks was −19.3 and +97.4%, respectively. One-year OS and SSE-free rate at the end of active follow-up were 78 and 89%, respectively. The ALP response rate was 31%, while the PSA response rate was 6%. Grade 3/4 treatment-emergent adverse events observed in ≥10% of patients included decreased lymphocyte count (14%), anemia (14%), anorexia (10%), and bone pain (10%).

Conclusions

Radium-223 is effective and well tolerated in Japanese patients with CRPC and bone metastases. Results were comparable with the Alpharadin in Symptomatic Prostate Cancer Patients (ALSYMPCA) trial.

Clinical trial registration

ClinicalTrials.gov NCT01929655.

Electronic supplementary material

The online version of this article (doi:10.1007/s10147-017-1176-0) contains supplementary material, which is available to authorized users.

PSA declines and survival in patients with metastatic castration-resistant prostate cancer treated with enzalutamide: A retrospective case-report study

RATIONALE

PSA responses have been associated with a survival benefit in patients treated with enzalutamide in retrospective analyses.

PATIENT CONCERNS

However the prognostic value of PSA declines in highly pretreated patients receiving enzalutamide remains to be defined.

DIAGNOSES AND INTERVENTATIONS

Medical records of patients with documented mCRPC treated with enzalutamide between September 2011 and August 2016 were reviewed at multiple participating centers and assessed for overall survival (OS), PSA variations, and other variables of interest. Univariable and multivariable analyses were conducted.

OUTCOMES

A total of 129 patients received enzalutamide. PSA response rates (>50% PSA declines) were 58/119 (48.7%), 58/115 (50.4%), 54/110 (49.1%), and 47/91 (51.7%) at weeks 4, 8, 12, and 16, respectively. Having a PSA response was a statistically significant prognostic factor of improved OS at 8 and 12 weeks in univariable analysis, whereas it was significant at 12 weeks in the multivariable analysis. Patients treated with enzalutamide had a median OS of 7.8 months.

LESSONS

Our study supports the prognostic value of PSA declines in heavily treated patients receiving enzalutamide.

First-line management of metastatic castrate-resistant prostate cancer patients: Audit of real-life practices

BACKGROUND

No reliable guidelines are available for choosing the best option between docetaxel and new hormonal therapies (NHTs) (i.e., abiraterone and enzalutamide) in first-line therapy for metastatic castration-resistant prostate cancer (mCRPC) patients. We performed an audit of real-life practices.

METHODS

We built an online questionnaire and distributed it with the help of French oncology networks. This questionnaire was sent to 481 physicians who treat patients with mCRPC. All of the answers were declarative, individual, and anonymized. A descriptive analysis was done. A univariate logistic regression analysis was performed for the criteria of choice between docetaxel and NHTs.

RESULTS

From March to July 2015, 109/481 physicians (22.6%) completed the questionnaire. The selection criteria for initially choosing docetaxel were as follows: presence of visceral metastases (79.8%), heavy tumor burden (68.8%), aggressive tumor disease (66.1%), and short-term efficacy of castration (66.1%). The selection criteria for initially choosing NHTs were as follows: long-term efficacy of castration (66.1%), higher age (67.9%), low tumor grade (56.9%), and absence of symptoms (54.1%). With docetaxel, the first tumor assessment was typically performed after three (1-6) cycles, including prostate-specific antigen (PSA) testing (96.3%), a thoraco-abdominopelvic CT scan (68.8%), and bone scintigraphy (59.6%). With NHTs, tumor assessment was mainly performed after 3 months of treatment (1-6) and included PSA testing, a thoraco-abdominopelvic CT, and bone scintigraphy in 90.8%, 61.5%, and 63.3% of cases, respectively.

CONCLUSIONS

This is the first study assessing real-life practices among physicians who treat patients with mCRPC. These practices were found to be homogeneous.

Prognostic impact of pretreatment neutrophil-to-lymphocyte ratio in castration-resistant prostate cancer patients treated with first-line docetaxel

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR), a measure of systemic inflammatory response, has been associated with poor outcome in several solid tumors, including prostate cancer. We retrospectively investigated the prognostic role of pretreatment NLR in metastatic castration-resistant prostate cancer (mCRPC) patients treated with first-line docetaxel.

METHODS

All CRPC patients treated with first-line docetaxel at two Italian institutions, with available data about baseline neutrophil and lymphocyte values, were included in this retrospective analysis. Patients were divided in two groups according to NLR ratio (low NLR: ≤3; high NLR: >3). Outcome measures were progression-free (PFS) and overall survival (OS), measured from the start of docetaxel treatment. Univariate and multivariate analysis (adjusting for baseline prostate-specific antigen, alkaline phosphatase, lactate dehydrogenase, hemoglobin, albumin, performance status, use of opioids and presence of visceral disease) were performed.

RESULTS

One hundred and seventy-nine patients treated between 2004 and 2016 were analyzed and 110 had information about pretreatment NLR. Forty-six patients (42%) had low NLR and 64 (58%) had high NLR. Median PFS was 8.8 months in patients with low NLR versus 7.3 months in those with high NLR [hazard ratio (HR) 1.12, 95% confidence interval (CI) 0.75-1.69, p = .58]. Median OS was 34.9 months in patients with low NLR versus 20.2 months in those with high NLR (HR 1.85, 95% CI 1.07-3.19, p = .02). At multivariate analysis, NLR confirmed an independent impact on OS (HR 3.16, 95% CI 1.50-6.65, p = .002).

CONCLUSION

In this retrospective series, metastatic CRPC patients who started first-line docetaxel with a low pretreatment NLR had a significantly better survival. In addition to known prognostic factors, NLR can be useful to improve prognostic evaluation of patients in this setting.

Clinical outcomes and survival surrogacy studies of prostate-specific antigen declines following enzalutamide in men with metastatic castration-resistant prostate cancer previously treated with docetaxel

BACKGROUND

In the AFFIRM trial, enzalutamide significantly increased overall survival (OS) for men with metastatic castration‐resistant prostate cancer (mCRPC) after chemotherapy versus placebo and significantly decreased prostate‐specific antigen (PSA) levels. The goal of this post hoc analysis was to associate levels of PSA decline from baseline after enzalutamide with clinical outcomes in the postchemotherapy mCRPC setting.

METHODS

Men in the AFFIRM trial (n = 1199) were grouped by maximal PSA decline in the first 90 days of treatment. Kaplan‐Meier estimates evaluated the association of defined PSA changes from baseline with OS, progression‐free survival (PFS), radiographic PFS (rPFS), and pain response. Each PSA decline category was assessed for OS surrogacy using Prentice criteria, proportion of treatment effect explained (PTE), and proportion of variation explained.

RESULTS

Men treated with enzalutamide had improved OS (hazard ratio, 0.63; P < .001) and higher rates of PSA decline (odds ratio, >19.0; P < .001) versus placebo. PSA declines of any, ≥30%, ≥50%, and ≥90% with enzalutamide were strongly associated with greater OS, PSA PFS, rPFS (P < .001), and pain response (P < .026) versus PSA increase/no decline. Any, ≥30%, and ≥50% declines in PSA resulted in the PTE range of 1.07‐1.29, where treatment was no longer significant after adjustment for decline measures (P > .20).

CONCLUSIONS

PSA declines of any, ≥30%, and ≥50% following enzalutamide were associated with greater clinical and pain response and improvements in PFS and OS. Surrogacy of PSA decline for OS was not fully established, possibly due to lack of PSA declines with placebo, and discordant results between PSA and imaging responses over time, and because some declines were not durable due to rapid resistance development. However, a lack of PSA decline by 90 days following enzalutamide treatment was a poor prognosis indicator in this setting. Conclusions from sensitivity analyses of maximal PSA decline from baseline over the entire treatment period are consistent with PSA declines restricted to the first 90 days. Cancer 2017;123:2303–2311. © 2017 American Cancer Society.

A post hoc analysis of the randomized, double‐blind AFFIRM trial revealed that postenzalutamide prostate‐specific antigen declines of any, ≥30%, and ≥50% are associated with greater clinical and pain response. The decline criteria explain a large proportion of treatment effect on survival improvements but do not fulfill the criteria for surrogacy.

Feasibility of classical secondary hormonal therapies prior to docetaxel therapy in Japanese patients with castration-resistant prostate cancer: Multicenter retrospective study

BACKGROUND

We retrospectively analyzed castration-resistant prostate cancer (CRPC) patients treated with secondary hormonal therapies (SHTs) prior to docetaxel therapy.

METHODS

The cases of 73 CRPC patients who underwent docetaxel therapy in 2005-2011 at four hospitals in Ibaraki, Japan were analyzed. We determined the cause-specific survival (CSS) from the start of docetaxel therapy and the time point of CRPC diagnosis, and we compared the CSS achieved with/without prior classical SHTs, which were defined as low-dose steroid and estramustine phosphate.

RESULTS

Of the 73 enrolled patients, 26 underwent docetaxel therapy (DOC group), and 47 underwent SHTs (SHTs-DOC group) as the initial treatment for CRPC. In the docetaxel therapy, the rate of prostate-specific antigen responses were higher in the DOC group compared with the SHTs-DOC group (76.9% vs. 44.7%, P = 0.0066). The median CSS from the docetaxel therapy initiation was not significant but longer in the DOC group than in the SHTs-DOC group (23.4 months vs. 16.6 months, P = 0.0969). However, the median CSS from the time of CRPC diagnosis did not significantly differ between the DOC and SHTs-DOC groups (23.4 months vs. 24.7 months, P = 0.9233). In a univariate analysis, pain and visceral metastasis appeared to be risk factors for the CSS in the SHTs-DOC group. The patients with pain and/or visceral metastasis had significantly poorer survival than those without these factors in the SHTs-DOC group (31.5 months vs. 16.8 months, P = 0.0053).

CONCLUSION

The induction of SHTs prior to docetaxel therapy is an acceptable treatment option with some survival benefits for CRPC patients without pain and visceral metastases.

Predicting Time From Metastasis to Overall Survival in Castration-Resistant Prostate Cancer: Results From SEARCH

OBJECTIVE

To identify the predictors of time from initial diagnosis of metastatic castration-resistance prostate cancer (mCRPC) to all-cause death within the Shared Equal Access Regional Cancer Hospital cohort.

PATIENTS AND METHODS

We performed a retrospective analysis of 205 mCRPC men. Overall survival was estimated and plotted using the Kaplan-Meier method. The uni- and multivariable overall survival predictors were evaluated with the Cox proportional hazards model. A nomogram was generated to predict overall survival at 1, 2, 3, and 5 years after mCRPC. Concordance index and calibration plot were obtained.

RESULTS

A total of 170 men (83%) died over a median follow-up of 41 months. In univariable analysis, older age, more remote year of mCRPC, nonblack race, greater number of bone metastasis, higher prostate-specific antigen (PSA) levels, shorter PSA doubling time, and faster PSA velocity at mCRPC diagnosis were significantly associated with shorter overall survival (all P < .05). In multivariable analysis, older age, more remote year of mCRPC, greater number of bone metastasis, higher PSA levels, and shorter PSA doubling time at mCRPC diagnosis remained significantly associated with shorter overall survival (all P < .05). On the basis of these variables, a nomogram was generated yielding a concordance index of 0.67 and good calibration.

CONCLUSION

The use of clinical parameter such as age, disease burden, and PSA levels and kinetics can be used to estimate overall survival in mCRPC patients.

Integrated Analysis of Multiple Biomarkers from Circulating Tumor Cells Enabled by Exclusion-Based Analyte Isolation

PURPOSE

There is a critical clinical need for new predictive and pharmacodynamic biomarkers that evaluate pathway activity in patients treated with targeted therapies. A microscale platform known as VERSA (versatile exclusion-based rare sample analysis) was developed to integrate readouts across protein, mRNA, and DNA in circulating tumor cells (CTC) for a comprehensive analysis of the androgen receptor (AR) signaling pathway.

EXPERIMENTAL DESIGN

Utilizing exclusion-based sample preparation principles, a handheld chip was developed to perform CTC capture, enumeration, quantification, and subcellular localization of proteins and extraction of mRNA and DNA. This technology was validated across integrated endpoints in cell lines and a cohort of patients with castrate-resistant prostate cancer (CRPC) treated with AR-targeted therapies and chemotherapies.

RESULTS

The VERSA was validated in cell lines to analyze AR protein expression, nuclear localization, and gene expression targets. When applied to a cohort of patients, radiographic progression was predicted by the presence of multiple AR splice variants and activity in the canonical AR signaling pathway. AR protein expression and nuclear localization identified phenotypic heterogeneity. Next-generation sequencing with the FoundationOne panel detected copy number changes and point mutations. Longitudinal analysis of CTCs identified acquisition of multiple AR variants during targeted treatments and chemotherapy.

CONCLUSIONS

Complex mechanisms of resistance to AR-targeted therapies, across RNA, DNA, and protein endpoints, exist in patients with CRPC and can be quantified in CTCs. Interrogation of the AR signaling pathway revealed distinct patterns relevant to tumor progression and can serve as pharmacodynamic biomarkers for targeted therapies. Clin Cancer Res; 1-11. ©2016 AACR.

High Absolute Monocyte Count Predicts Poor Clinical Outcome in Patients with Castration-Resistant Prostate Cancer Treated with Docetaxel Chemotherapy

BACKGROUND

The association of peripheral monocyte count and prostate cancer progression is not well characterized.

OBJECTIVE

Our aim was to investigate the prognostic value of absolute monocyte count (AMC), which is thought to modulate immune response in the tumor microenvironment, in castration-resistant prostate cancer (CRPC) patients treated with docetaxel chemotherapy.

METHODS

We retrospectively reviewed the medical records of 214 CRPC patients who received docetaxel therapy and were used as the training and validation set. Docetaxel at a dose of 75 mg/m² was administered every 3 or 4 weeks. Clinicopathological factors and laboratory data were collected to assess the prognostic factors for overall survival (OS) and progression-free survival (PFS).

RESULTS

In the training set, the median age was 73.0 years, and the median prostate-specific antigen (PSA) value was 31.7 ng/ml at initial treatment. The median OS and PFS were 23.0 months (range 1.20-84.0) and 11.2 months (range 3.6-78.0), respectively. According to multivariable Cox regression analysis, AMC ≥400/uL, PSA level ≥20 ng/ml, and Hb <10 mg/dL were associated with increased risk of PSA progression [hazard ratio (HR) 2.06, p = 0.005; HR 2.39, p = 0.002; and HR 2.38, p = 0.024, respectively]. Moreover, multivariate analysis for OS indicated that AMC ≥400/uL, pretreatment PSA level ≥20 ng/ml, presence of visceral metastasis, and alkaline phosphatase ≥284 U/L were independent prognostic factors for shortened OS (HR 2.07, p = 0.004; HR 2.18, p = 0.007; HR 2.11, p = 0.011; and HR 1.67, p = 0.048, respectively). According to the validation set, high AMC remained an independent prognostic factor for PFS and OS (HR 2.26, p = 0.001; and HR 3.10, p < 0.001, respectively).

CONCLUSIONS

Elevated monocyte counts were associated with aggressive tumor features and poor survival outcomes of patients with CRPC treated with docetaxel chemotherapy.

Prognostic factors and risk stratification in patients with castration-resistant prostate cancer receiving docetaxel-based chemotherapy

BACKGROUND

While novel drugs have been developed, docetaxel remains one of the standard initial systemic therapies for castration-resistant prostate cancer (CRPC) patients. Despite the excellent anti-tumor effect of docetaxel, its severe adverse effects sometimes distress patients. Therefore, it would be very helpful to predict the efficacy of docetaxel before treatment. The aims of this study were to evaluate the potential value of patient characteristics in predicting overall survival (OS) and to develop a risk classification for CRPC patients treated with docetaxel-based chemotherapy.

METHODS

This study included 79 patients with CRPC treated with docetaxel. The variables, including patient characteristics at diagnosis and at the start of chemotherapy, were retrospectively collected. Prognostic factors predicting OS were analyzed using the Cox proportional hazard model. Risk stratification for overall survival was determined based on the results of multivariate analysis.

RESULTS

PSA response ≥50 % was observed in 55 (69.6 %) of all patients, and the median OS was 22.5 months. The multivariate analysis showed that age, serum PSA level at the start of chemotherapy, and Hb were independent prognostic factors for OS. In addition, ECOG performance status (PS) and the CRP-to-albumin ratio were not significant but were considered possible predictors for OS. Risk stratification according to the number of these risk factors could effectively stratify CRPC patients treated with docetaxel in terms of OS.

CONCLUSIONS

Age, serum PSA level at the start of chemotherapy, and Hb were identified as independent prognostic factors of OS. ECOG PS and the CRP-to-albumin ratio were not significant, but were considered possible predictors for OS in Japanese CRPC patients treated with docetaxel. Risk stratification based on these factors could be helpful for estimating overall survival.

Prognostic value of a computer-aided diagnosis system involving bone scans among men treated with docetaxel for metastatic castration-resistant prostate cancer

BACKGROUND

The bone scan index (BSI), which is obtained using a computer-aided bone scan evaluation system, is anticipated to become an objective and quantitative clinical tool for evaluating bone metastases in prostate cancer. Here, we assessed the usefulness of the BSI as a prognostic factor in patients with metastatic castration-resistant prostate cancer (mCRPC) treated using docetaxel.

METHODS

We analyzed 41 patients who received docetaxel for mCRPC. The Bonenavi system was used as the calculation program for the BSI. The utility of the BSI as a predictor of overall survival (OS) after docetaxel was evaluated. The Cox proportional hazards model was used to investigate the association between clinical variables obtained at docetaxel treatment, namely PSA, patient age, liver metastasis, local therapy, hemoglobin (Hb), lactase dehydrogenase (LDH), albumin (Alb), PSA doubling time, and BSI and OS.

RESULTS

The median OS after docetaxel therapy was 17.7 months. Death occurred in 22 (53.7%) patients; all deaths were caused by prostate cancer. In multivariate analysis, three factors were identified as significant independent prognostic biomarkers for OS after docetaxel; these were liver metastases (yes vs no; HR, 3.681; p = 0.026), Alb (<3.9 vs ≥ 3.9; HR, 3.776; p = 0.020), and BSI (>1% vs ≤ 1%; HR, 3.356; p = 0.037). We evaluated the discriminatory ability of our models including or excluding the BSI by quantifying the c-index. The BSI improved the c-index from 0.758 to 0.769 for OS after docetaxel. CRPC patients with a BSI >1 had a significantly shorter OS than patients with a BSI ≤ 1 (p = 0.029).

CONCLUSIONS

The BSI, liver metastases and Alb were independent prognostic factors for OS after docetaxel. The BSI might be a useful tool for risk stratification of mCRPC patients undergoing docetaxel treatment.

Cost Prediction Using a Survival Grouping Algorithm: An Application to Incident Prostate Cancer Cases

BACKGROUND

Prognostic classification approaches are commonly used in clinical practice to predict health outcomes. However, there has been limited focus on use of the general approach for predicting costs. We applied a grouping algorithm designed for large-scale data sets and multiple prognostic factors to investigate whether it improves cost prediction among older Medicare beneficiaries diagnosed with prostate cancer.

METHODS

We analysed the linked Surveillance, Epidemiology and End Results (SEER)-Medicare data, which included data from 2000 through 2009 for men diagnosed with incident prostate cancer between 2000 and 2007. We split the survival data into two data sets (D0 and D1) of equal size. We trained the classifier of the Grouping Algorithm for Cancer Data (GACD) on D0 and tested it on D1. The prognostic factors included cancer stage, age, race and performance status proxies. We calculated the average difference between observed D1 costs and predicted D1 costs at 5 years post-diagnosis with and without the GACD.

RESULTS

The sample included 110,843 men with prostate cancer. The median age of the sample was 74 years, and 10% were African American. The average difference (mean absolute error [MAE]) per person between the real and predicted total 5-year cost was US$41,525 (MAE US$41,790; 95% confidence interval [CI] US$41,421-42,158) with the GACD and US$43,113 (MAE US$43,639; 95% CI US$43,062-44,217) without the GACD. The 5-year cost prediction without grouping resulted in a sample overestimate of US$79,544,508.

CONCLUSION

The grouping algorithm developed for complex, large-scale data improves the prediction of 5-year costs. The prediction accuracy could be improved by utilization of a richer set of prognostic factors and refinement of categorical specifications.

Does Gleason score at initial diagnosis predict efficacy of abiraterone acetate therapy in patients with metastatic castration-resistant prostate cancer? An analysis of abiraterone acetate phase III trials

BACKGROUND

The usefulness of Gleason score (<8 or ≥8) at initial diagnosis as a predictive marker of response to abiraterone acetate (AA) plus prednisone in patients with metastatic castration-resistant prostate cancer (mCRPC) was explored retrospectively.

PATIENTS AND METHODS

Initial diagnosis Gleason score was obtained in 1048 of 1195 (COU-AA-301, post-docetaxel) and 996 of 1088 (COU-AA-302, chemotherapy-naïve) patients treated with AA 1 g plus prednisone 5 mg twice daily by mouth or placebo plus prednisone. Efficacy end points included radiographic progression-free survival (rPFS) and overall survival (OS). Distributions and medians were estimated by Kaplan-Meier method and hazard ratio (HR) and 95% confidence interval (CI) by Cox model.

RESULTS

Baseline characteristics were similar across studies and treatment groups. Regardless of Gleason score, AA treatment significantly improved rPFS in post-docetaxel [Gleason score <8: median, 6.4 versus 5.5 months (HR = 0.70; 95% CI 0.56-0.86), P = 0.0009 and Gleason score ≥8: median, 5.6 versus 2.9 months (HR = 0.58; 95% CI 0.48-0.72), P < 0.0001] and chemotherapy-naïve patients [Gleason score <8: median, 16.5 versus 8.2 months (HR = 0.50; 95% CI 0.40-0.62), P < 0.0001 and Gleason score ≥8: median, 13.8 versus 8.2 months (HR = 0.61; 95% CI 0.49-0.76), P < 0.0001]. Clinical benefit of AA treatment was also observed for OS, prostate-specific antigen (PSA) response, objective response and time to PSA progression across studies and Gleason score subgroups.

CONCLUSION

OS and rPFS trends demonstrate AA treatment benefit in patients with pre- or post-chemotherapy mCRPC regardless of Gleason score at initial diagnosis. The initial diagnostic Gleason score in patients with mCRPC should not be considered in the decision to treat with AA, as tumour metastases may no longer reflect the histology at the time of diagnosis.

CLINICAL TRIALS NUMBER

COU-AA-301 (NCT00638690); COU-AA-302 (NCT00887198).

Metastatic Prostatic Ductal Adenocarcinoma Successfully Treated with Docetaxel Chemotherapy: A Case Report

A 68-year-old man presented with gross hematuria. A papillary urethral tumor adjacent to the verumontanum was found by cystourethroscopy. Serum prostate-specific antigen (PSA) was 3.246 ng/ml. A transurethral biopsy specimen was most suggestive of a primary urothelial carcinoma of the prostate, for which a radical cystoprostatectomy was performed. The final pathology was prostatic ductal adenocarcinoma with very focal acinar features (Gleason score 5 %plus; 4 = 9, pT3bN0M0). Local recurrence and pelvic bone metastases developed 17 months later, and his PSA rose to 10.806 ng/ml. He was treated with combined androgen blockade and radiation. Two years later, the lesion showed progressive growth. Treatment followed with docetaxel (70 mg/m(2) every 3 weeks) and prednisolone 5 mg twice daily. After 10 cycles of chemotherapy, all lesions disappeared and PSA decreased to <0.005 ng/ml. Three years after chemotherapy, he maintains a complete response without any additional treatments. Docetaxel chemotherapy can be an effective treatment for patients with recurrent prostatic ductal adenocarcinoma.

Expert opinion on first-line therapy in the treatment of castration-resistant prostate cancer

Treatment of metastatic castration-resistant prostate cancer (mCRPC) has been revolutionized in recent years. It is well known that androgen receptor is still active in most patients with disease progression and serum testosterone levels <50 ng/dL. Moreover, further hormonal maneuvers, either through decreasing androgen levels (abiraterone) or by targeting the androgen receptor (AR) pathway (enzalutamide), prolong survival. In addition, a new cytostatic able to overcome docetaxel resistance, cabazitaxel, and the radioisotope radium 223 have been incorporated to the armamentarium of mCRPC. mCRPC is not only a heterogeneous tumor, it changes over time developing neuroendocrine features or selection of clones resistant to hormonal maneuvers. In addition, the multiplicity of current treatments, make it necessary to design algorithms that help the specialist to choose the most appropriate treatment for a particular patient. The lack of randomized trials comparing face to face the different available options limit the scope of this review. In this article, the authors describe the prognostic factors for first line therapy in patients with mCRPC, and propose a treatment algorithm for mCRPC based on the levels of scientific evidence available and, if not available, on the consensus between medical professionals. Finally, the panel discuss how to define progressive disease in the setting of mCRPC and treatment with targeted therapies.

High neutrophil-to-lymphocyte ratio predicts poor clinical outcome in patients with castration-resistant prostate cancer treated with docetaxel chemotherapy

OBJECTIVE

To evaluate the prognostic significance of the neutrophil-to-lymphocyte ratio in patients receiving chemotherapy with docetaxel for castration-resistant prostate cancer.

METHODS

A total of 57 castration-resistant prostate cancer patients treated between 2009 and 2014 were included in the present retrospective study. All patient data, including clinicopathological factors, were assessed. Univariate and multivariate Cox regression models were used to predict overall survival and progression-free survival after chemotherapy initiation.

RESULTS

The median overall survival and progression-free survival were determined as 19.0 months (range 1-61 months) and 10.0 months (range 1-56 months), respectively. The cut-off level of the neutrophil-to-lymphocyte ratio was set as the median value of 3.5 among all patients in this study. In Kaplan-Meier analysis, the median overall survival and progression-free survival were shorter in patients with a high neutrophil-to-lymphocyte ratio compared with those with a low neutrophil-to-lymphocyte ratio (15 vs 20 months, P = 0.0125; and 9.5 vs 15 months, P = 0.0132, respectively). The overall survival and progression-free survival periods in patients with a high neutrophil-to-lymphocyte ratio were significantly shorter than those of patients with a low neutrophil-to-lymphocyte ratio (P = 0.0178 and 0.0176, respectively). In the multivariate analysis, a high neutrophil-to-lymphocyte ratio was an independent predictor of overall survival and progression-free survival (hazard ratio 2.728, 95% confidence interval 1.05-7.09, P = 0.039; and hazard ratio 2.376, 95% confidence interval 1.12-5.06, P=0.024, respectively).

CONCLUSION

The present study results suggest that the neutrophil-to-lymphocyte ratio is a useful prognostic factor in patients with castration-resistant prostate cancer treated by docetaxel chemotherapy. These findings might be useful in determining treatment strategies in the future.

Activity of enzalutamide in men with metastatic castration-resistant prostate cancer is affected by prior treatment with abiraterone and/or docetaxel

BACKGROUND

Enzalutamide and abiraterone are new androgen-axis disrupting treatments for metastatic castration-resistant prostate cancer (mCRPC). We examined the response and outcomes of enzalutamide-treated mCRPC patients in the real-world context of prior treatments of abiraterone and/or docetaxel.

METHODS

We conducted a seven-institution retrospective study of mCRPC patients treated with enzalutamide between January 2009 and February 2014. We compared the baseline characteristics, PSA declines, PSA progression-free survival (PSA-PFS), duration on enzalutamide and overall survival (OS) across subgroups defined by prior abiraterone and/or docetaxel.

RESULTS

Of 310 patients who received enzalutamide, 36 (12%) received neither prior abiraterone nor prior docetaxel, 79 (25%) received prior abiraterone, 30 (10%) received prior docetaxel and 165 (53%) received both prior abiraterone and prior docetaxel. Within these groups, respectively, ⩾30% PSA decline was achieved among 67, 28, 43 and 24% of patients; PSA-PFS was 5.5 (95% CI 4.2-9.1), 4.0 (3.2-4.8), 4.1 (2.9-5.4) and 2.8 (2.5-3.2) months; median duration of enzalutamide was 9.1 (7.3-not reached), 4.7 (3.7-7.7), 5.4 (3.8-8.4) and 3.9 (3.0-4.6) months. Median OS was reached only for the patients who received both prior abiraterone and docetaxel and was 12.2 months (95% CI 10.7-16.5). 12-month OS was 78% (59-100%), 64% (45-90%), 77% (61-97%) and 51% (41-62%). Of 70 patients who failed to achieve any PSA decline on prior abiraterone, 19 (27%) achieved ⩾30% PSA decline with subsequent enzalutamide.

CONCLUSIONS

The activity of enzalutamide is blunted after abiraterone, after docetaxel, and still more after both, suggesting subsets of overlapping and distinct mechanisms of resistance.

Development of a preliminary nomogram to predict progression of bone scan for castration-resistant prostate cancer

The optimal time to perform bone scan to detect new metastasis during the castration-resistant prostate cancer (CRPC) stage remains undefined. This study attempted to identify predictors of progression of bone scan for CRPC, and use such information to develop a nomogram to predict the optimal time of examinations for bone scan. The analysis included 167 CRPC patients. Progression of bone lesion, as evaluated by bone scan, occurred in 64 (38.3%) cases. A logistic regression identified the following three risk factors: short time to prostate-specific antigen (PSA) progression, severe pain, and short PSA doubling time (PSADT) (P<0.05 for all). A nomogram model was constructed to predict progression of bone scan using time to PSA progression and severe pain as dichotomized variables and PSADT as a continuous variable. The result indicated that a predictive nomogram model showed a bootstrap-corrected concordance index of 0.762 and good calibration using the three readily available variables, and there were worse prognosis and higher progression rate of bone scan for patients with time to PSA progression <6.6 months, severe pain, and short PSADT (<2 months). In conclusion, short time to PSA progression, severe pain, and short PSADT are three risk factors of progression of bone scan for CRPC patients. The predictive nomogram model may be a valuable numerical assessment tool for patient consultation and treatment decision.

Gastrointestinal metastases from prostate cancer: a review of the literature

ABSTRACT 

The availability of active new drugs for the treatment of advanced castration-resistant prostate cancer has significantly prolonged overall survival, thus changing the natural history of the disease and raising the likelihood of observing metastases in atypical sites. This review of the literature describes the frequency, clinical-pathological features and presenting symptoms of non-liver gastrointestinal metastases (GIm) from prostate cancer. Its purpose is to increase clinical awareness of the increasing incidence of such GIm, contributing to the early detection, accurate diagnosis and, when feasible, appropriate management.