Bone targeted therapy and skeletal related events in the era of enzalutamide and abiraterone acetate for castration resistant prostate cancer with bone metastases.

BACKGROUND: In an era of multiple life-prolonging therapies for metastatic castration resistant prostate cancer (mCRPC), the optimal timing of initiation and duration of antiresorptive bone targeted therapy (BTT) to prevent skeletal related events (SREs) is unknown. METHODS: To assess practice patterns of BTT use and its associations with clinical outcomes in a high-volume center in the modern era of metastatic CRPC management, a retrospective cohort of patients treated for mCRPC with BM between 2007 and 2017 was identified from a single institutions clinical research database. Study endpoints included time from the diagnosis of CRPC to the onset of SRE or OS. Cox proportional hazards model assessed association of BTT use with time to first SRE and OS. RESULTS: In total, 249 patients were identified; median follow-up was 7.7 (95%CI: 5.7-10.2) years. On multivariable analysis, patients with 4 or more BM at diagnosis of mCRPC who received BTT with abiraterone acetate or enzalutamide as first line therapy had a 42% reduced risk of developing an SRE (HR 0.58; 95%CI: 0.36-0.95) compared to those who never received BTT or received it in second line. No such effect was observed in patients with 1-3 BM. No OS difference was noted in patients who received BTT, whether with first line therapy or without. This study is limited by retrospective nature at a single institution. CONCLUSIONS: Our hospital registry data indicate a potential benefit in terms of SRE prevention for early use of antiresorptive BTT in combination with life prolonging CRPC therapies for patients with CRPC and at least 4 BM.

Association between CD8 and PD-L1 expression and outcomes after radical prostatectomy for localized prostate cancer.

BACKGROUND: Characterization of markers of both immune suppression and activation may provide more prognostic information than assessment of single markers in localized prostate cancer. We therefore sought to determine the association between CD8 and PD-L1 expression in localized prostate tumors and biochemical recurrence (BCR) and metastasis-free survival (MFS). METHODS: Tissue microarrays were constructed on 109 men undergoing radical prostatectomy (RP) for localized prostate cancer at Dana-Farber Cancer Institute between 1991 and 2008. Fluorescence immunohistochemistry was used to evaluate the expression of six immune markers (CD3, CD4, CD8, PD-1, PD-L1, FOXP3). Quantitative multispectral imaging analysis was used to calculate the density of each marker, which was dichotomized by the median as "high" or "low." Cox proportional hazards regression models and Kaplan-Meier analyses were used to analyze associations between immune marker densities and time to BCR and MFS. RESULTS: Over a median follow-up of 8.1 years, 55 (51%) and 39 (36%) men developed BCR and metastases, respectively. Median time to BCR was shorter in men with low CD8 (hazard ratio [HR] = 2.27 [1.27-4.08]) and high PD-L1 expression (HR = 2.03 [1.17-3.53]). While neither low CD8 or high PD-L1 alone were independent predictors of BCR or MFS on multivariable analysis, men with low CD8 and/or high PD-L1 had a significantly shorter time to BCR (median 3.5 years vs. NR) and MFS (median 10.8 vs. 18.4 years) compared to those with high CD8 and low PD-L1 expression. The main limitation is the retrospective and singe-center nature of the study. CONCLUSION: The presence of higher CD8 and lower PD-L1 expression in prostatectomy specimens was associated a low risk of biochemical relapse and metastatic disease. These findings are hypothesis-generating and further study is needed.

Impact of new systemic therapies on overall survival of patients with metastatic castration-resistant prostate cancer in a hospital-based registry.

BACKGROUND: In 2004, docetaxel was shown to prolong the overall survival (OS) of patients with metastatic castration-resistance prostate cancer (mCRPC). Since 2010, five new systemic therapies have been shown to prolong OS in men with mCRPC. We sought to evaluate the aggregate impact of these newer therapies on the OS of patients with mCRPC. METHODS: Two cohorts of patients diagnosed with mCRPC between 2004 and 2007, treated with drugs used in the limited treatment era only (A), and between 2010 and 2013, treated also with newer therapies (B), were identified from the Dana-Farber Cancer Institute database. The analysis endpoint was OS within 5 years after mCRPC diagnosis. Kaplan-Meier method assessed time-to-event distributions with median (95% confidence interval (CI)). A piece-wise regression model assessed the association between endpoint and treatment cohorts with estimate of hazard ratio (HR) with 95% CI within two time segments in univariate and multivariable analyses adjusting for relevant covariates. RESULTS: Compared to cohort A (n = 318), cohort B (n = 272) patients in newer therapy era demonstrated an OS advantage (2.8 vs. 2.2 years) with a 41% decreased risk of death (HR = 0.59; 95% CI, 0.47-0.74; P < 0.0001), and a 3-year OS rate of 46% vs. 33%. This benefit was accentuated (median OS 2.7 vs. 2.1 years; HR = 0.46; 95% CI, 0.32-0.67; P < 0.0001) in patients who initially presented with de-novo metastatic disease (de-novo). On multivariable analysis, longer OS was associated with cohort B vs. A and performance status 0 vs. 1. CONCLUSIONS: Using a single-institution registry, mCRPC patients treated since 2010 had a significant survival improvement vs. those treated before 2010. Although the median survival was only modestly improved and less than predicted when simply adding each newer drug survival advantage, the cumulative benefit from the new therapies was more pronounced in longer-term survivors and de-novo patients.

Compound Genomic Alterations of TP53, PTEN, and RB1 Tumor Suppressors in Localized and Metastatic Prostate Cancer.

BACKGROUND: TP53, PTEN, and RB1 tumor suppressor genes (TSGs) are recurrently altered in treatment-resistant prostate cancer. Cooperative loss of two or more TSGs may drive more aggressive disease. OBJECTIVE: To determine clinical outcomes of single and compound TSG alterations across the spectrum of prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: Massively parallel targeted sequencing using castration-sensitive prostate cancer (CSPC; localized [L] and metastatic [M1]) and castration-resistant prostate cancer (CRPC) specimens (n=285). TSG altered (TSG-alt) was any copy number loss or deleterious mutation of one or more TSGs (TP53, PTEN, and RB1). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: For L-CSPC, event-free survival (EFS) and time to CRPC were estimated. For M1-CSPC and M1-CRPC, overall survival (OS) was estimated. Cox regression models assessed the association between cumulative TSG hits (zero hits vs one hit vs two to three hits) and outcomes with multivariable analyses adjusted for clinicopathological factors. RESULTS AND LIMITATIONS: TSG variants increased with advanced disease (L-CSPC: 39%; M1-CSPC: 63%, M1-CRPC: 92%). TSG-alt L-CSPC had shorter EFS (median 2.6yr, hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.22-3.13) and time to CRPC (median 9.5mo, HR 3.36, 95% CI 1.01-11.16). Cumulative gene hits led to an incremental risk of relapse (EFS: one gene, HR 1.69, 95% CI 0.99-2.87; two to three genes, HR 2.70, 95% CI 1.43-5.08; both versus zero genes, p=0.004). There was evidence of inferior OS with increasing TSG hits in the metastatic cohorts. Only four (8%) patients in the M1-CRPC cohort were TSG-neg, one of whom died after 5.2yr. Multivariable analyses adjusting for mutational and copy number burden did not demonstrate a significant independent association of increasing gene hits and poorer outcomes. CONCLUSIONS: Deleterious TSG variants are associated with an increased risk of relapse (L) and death (M1) in CSPC. Poorer outcomes are seen with compound gene hits in both early and advanced disease, and this may in part reflect increasing global genomic instability. PATIENT SUMMARY: Men with prostate tumors with compound tumor suppressor gene mutations have poorer outcomes. These findings help identify patients with aggressive features who may benefit from intensified treatment.

Clinical Outcomes of First-line Abiraterone Acetate or Enzalutamide for Metastatic Castration-resistant Prostate Cancer After Androgen Deprivation Therapy + Docetaxel or ADT Alone for Metastatic Hormone-sensitive Prostate Cancer.

BACKGROUND: The CHAARTED (ChemoHormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer) and STAMPEDE (Systemic Therapy in Advancing or Metastatic Prostate Cancer: Evaluation of Drug Efficacy) trials showed that the addition of docetaxel (D) to androgen deprivation therapy (ADT) prolonged longevity of men with metastatic hormone-sensitive prostate cancer (mHSPC). However, the impact of upfront D on subsequent therapies is still unexplored. As abiraterone acetate (AA) and enzalutamide (E) are the most commonly used first-line treatment for metastatic castration-resistant prostate cancer (mCRPC), we aimed to assess whether they maintained their efficacy after ADT+D versus ADT alone. PATIENTS AND METHODS: A cohort of patients with mCRPC treated between 2014 and 2017 with first-line AA or E for mCRPC was identified from 3 hospitals' institutional review board-approved databases. Patients were classified by use of D for mHSPC. This time frame was chosen as ADT+D became a valid therapeutic option for mHSPC in 2014, and it inherently entailed a short follow-up time on AA/E. The endpoints included overall survival from ADT start, overall survival from AA/E start, and time to AA/E start from ADT start. Differences between groups were assessed using the log-rank test. RESULTS: Of the 102 patients with mCRPC identified, 50 (49%) had previously received ADT alone, while 52 (51%) had ADT+D. No statistically significant difference in any of the evaluated outcomes was observed between the 2 cohorts. Yet, deaths in the ADT+D group were 12 versus 21 in the ADT alone, after a median follow-up of 24.4 and 29.8 months, respectively. CONCLUSION: In a cohort of ADT/ADT+D-treated patients with mCRPC with short times to first-line AA/E and follow-up, the efficacy of AA/E is similar regardless of previous use of D.

Duration of Androgen Deprivation Therapy for High-Risk Prostate Cancer: Application of Randomized Trial Data in a Tertiary Referral Cancer Center.

INTRODUCTION: We evaluated the incidence and predictors of the use of long-term (2-3 years) versus shorter term androgen deprivation therapy (ADT) in radiation-managed men with high-risk prostate cancer. PATIENTS AND METHODS: We identified 302 patients from the Dana-Farber Cancer Institute patient registry who had been diagnosed with high-risk prostate cancer (T3a or prostate-specific antigen [PSA] > 20 ng/mL or Gleason score 8-10) from 1993 to 2015. We assessed the intended duration of ADT and used multivariable Cox regression to evaluate the predictors of receiving a shorter course of ADT than recommended by the guidelines (< 2 years). RESULTS: The course of ADT intended by physicians increased after the 2008/2009 publication of trials showing the superiority of long-term versus short-term ADT, with 43.5% intending ≥ 2 years before versus 61.4% after (P = .014). Starting in 2010, 49.4% of patients actually received < 2 years of ADT. The most common reasons for receipt of shorter course ADT were intolerance of ADT side effects, patient comorbidity/age, the presence of T3a on magnetic resonance imaging only as the sole high-risk feature, or participation in a clinical trial. Moderate to severe comorbidity assessed using the Adult Comorbidity Evaluation-27 (adjusted hazard ratio [AHR] = 2.94), Gleason score < 8 (AHR = 5.66), and PSA < 20 ng/mL (AHR = 4.19) all predicted for receipt of shorter course ADT (P < .05 for all). CONCLUSION: In a tertiary-care setting, the rates of long-course ADT for high-risk disease have increased since the 2008/2009 trials supporting its use. However, approximately one half of patients continued to receive shorter course ADT, often because of intolerance of side effects, underlying comorbidity, or physician judgment about the aggressiveness of the disease.

Patients with Biopsy Gleason 9 and 10 Prostate Cancer Have Significantly Worse Outcomes Compared to Patients with Gleason 8 Disease.

PURPOSE: We examined differences in outcome in patients with biopsy Gleason score 8 vs 9-10 who received definitive local therapy. MATERIALS AND METHODS: Using an institutional database we identified a cohort of 847 patients with biopsy Gleason 8-10 disease who received definitive local therapy with radiation therapy or radical prostatectomy between January 2001 and December 2011. Multivariable Cox modeling was used to assess the association of Gleason score 8 vs 9-10 with time to biochemical recurrence, metastasis and overall survival, and evaluate treatment by Gleason score interaction. Median followup in the cohort was 5.3 years. RESULTS: Baseline patient characteristics were similar for biopsy Gleason 8 vs 9-10. Gleason 9-10 disease was associated with higher prostate specific antigen at diagnosis. As local treatment such patients were also more likely to have received radiation therapy (58% vs 46%, p = 0.001) and neoadjuvant/adjuvant androgen deprivation therapy (64% vs 49%, p <0.001). Those with higher grade disease were at increased risk for metastasis (HR 1.41, 95% CI 1.11-1.79). There was a trend toward an increased risk of death in Gleason 9-10 vs 8 cases (HR 1.28, 95% CI 0.98-1.66). The increased risk of death for Gleason 9-10 was mainly observed in patients treated with radical prostatectomy with or without additional radiation therapy (HR 1.74, 95% CI 1.15-2.65). CONCLUSIONS: Patients with localized biopsy Gleason 9-10 disease treated with definitive local therapy had worse outcomes than those diagnosed with biopsy Gleason 8 disease. Clinical trials are urgently needed that incorporate newer approaches to Gleason 9-10 cancer.

Role of androgen deprivation therapy in early salvage radiation among patients with prostate-specific antigen level of 0.5 or less.

BACKGROUND: The Radiation Therapy Oncology Group 96-01 randomized trial demonstrated the benefit of adding androgen deprivation therapy (ADT) to salvage radiotherapy for an increasing prostate-specific antigen (PSA) after prostatectomy, but it is unknown whether modern patients followed with ultrasensitive PSA and salvaged at a low PSA (ie, ≤ 0.5) also benefit from ADT. PATIENTS AND METHODS: The cohort comprised 108 patients who received radical prostatectomy (RP), were followed by ultrasensitive PSA, and received salvage radiotherapy at a PSA of 0.5 or less. Sixty patients had negative margins, and 48 patients had positive margins at RP. Cox multivariable regression analysis was performed to identify factors associated with time to secondary PSA failure and included PSA at salvage, year of treatment, Gleason score, ADT use, margin status, T stage, and PSA doubling time. Occurrence of distant metastases was documented. RESULTS: Median follow-up after radiation was 63.09 months. A total of 24 patients had a distant metastasis. In all patients, ADT use was associated with a decreased risk of recurrence (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.25-0.79; P = .006). On subgroup analysis, ADT was associated with a decreased risk of failure among patients with negative margins (HR, 0.27; 95% CI, 0.12-0.61; P = .002), but not among men with positive margins (HR, 0.78; 95% CI, 0.29-2.10; P = .63). CONCLUSIONS: Even patients followed with ultrasensitive PSA and salvaged early with a PSA ≤ 0.5 seem to benefit from the addition of ADT to salvage radiation. However, this benefit seemed to be limited to men with negative margins; thus, men with positive margins and PSA ≤ 0.5 may be good candidates for salvage radiation alone.

Elevated IL-8, TNF-α, and MCP-1 in men with metastatic prostate cancer starting androgen-deprivation therapy (ADT) are associated with shorter time to castration-resistance and overall survival.

BACKGROUND: Chemokines and cytokines have been implicated in progression to castration-resistant prostate cancer (CRPC). METHODS: Retrospective data were accessed from 122 men with serum samples drawn at a median of 0.5 months after starting ADT for metastatic prostate cancer. MCP-1, IL-1-ß, IL-2, IL-8, IL-6, and TNF-α levels were measured by multiplex electrochemiluminescence assays. A multivariable Cox model assessed the association of time to CRPC and overall survival by the protein levels and adjusted for clinical variables (age and prostate specific antigen (PSA) levels at start of ADT, race, ECOG status, and extent of metastases). Associations were reported as hazard ratio (HR) with 95% confidence interval (CI). RESULTS: Median follow-up and overall survival were 44 and 42.2 months, respectively. ECOG performance status (≥1 vs. 0) was negatively associated with overall survival [HR = 2.8 (1.1-7.0), P = 0.03], and PSA nadir < 0.2 was predictive of longer time to development of CRPC [HR = 0.3 (0.2-0.5), P < 0.0001]. The HR for time to CRPC by protein above the median was 1.4 (95% CI: 0.9, 2.2, P = 0.13) for IL-8; 1.3 (95% CI: 0.8, 2, P = 0.18) for TNF-α; 1.0 (95% CI: 0.7, 1.6, P = 0.95) for MCP-1. The HR for median overall survival for protein levels above the median was: 1.9 (95% CI: 1.0, 3.5, P = 0.04) for IL-8; 2.0 (95% CI: 1.1, 3.5, P = 0.02) for TNF-α; 1.7 (95% CI: 1.7, 3.0, P = 0.08) for MCP-1. There was no association with IL-1-ß, IL-2, or IL-6. CONCLUSION: Higher levels of inflammation-associated cytokines correlate with poorer prostate cancer outcomes and may guide strategies to improve prostate cancer therapy.

Elevated insulin-like growth factor binding protein-1 (IGFBP-1) in men with metastatic prostate cancer starting androgen deprivation therapy (ADT) is associated with shorter time to castration resistance and overall survival.

BACKGROUND: Insulin-like growth factor (IGF) and adipokines have been implicated in prostate cancer carcinogenesis. METHOD: Data from 122 men with serum samples drawn within 3 months of starting ADT for metastatic prostate cancer was accessed retrospectively. IGF-1, IGF binding protein (BP)-1, leptin, and adiponectin levels were measured by multiplex electrochemiluminescence assays. A multivariable Cox model assessed the association of time to castration resistant prostate cancer (CRPC) and overall survival by the protein levels, adjusted for clinical variables, age and prostate specific antigen (PSA) levels at start of ADT, race, ECOG status, extent of metastases and were reported as hazard ratio (HR) with 95% confidence interval (CI). RESULTS: Median follow-up and overall survival were 44 and 42.2 months, respectively. ECOG performance status (≥ 1 vs. 0) was negatively associated with overall survival [H = 2.8 (1.1-7.0), P = 0.03], and PSA nadir <0.2 was predictive of longer time to CRPC [HR = 0.3 (0.2-0.5), P < 0.0001]. The median time to CRPC by low, middle, and top IGFBP-1 tertile distribution was 20.7, 18.1, and 12.4 months, respectively, with HR for middle versus low tertile levels 3.1 (1.7-5), P = 0.0003, and for top versus low tertile levels was 2.4 (1.3-4.2), P = 0.003. The median overall survival by low, middle and top tertile IGFBP-1 level was 48.5, 46.4, and 32.8 months, respectively, with HR for top versus low tertile 2.5 (1.2-5.1), P = 0.01. There was no association with IGF-1, adiponectin and leptin. CONCLUSION: Elevated IGFBP-1 appears to be associated with shorter time to CRPC and lower overall survival in men with metastatic prostate cancer.

Association of prostate cancer risk Loci with disease aggressiveness and prostate cancer-specific mortality.

Genome-wide association studies have detected more than 30 inherited prostate cancer risk variants. While clearly associated with risk, their relationship with clinical outcome, particularly prostate cancer-specific mortality, is less well known. We investigated whether the risk variants are associated with various measures of disease aggressiveness and prostate cancer-specific mortality. In a cohort of 3,945 men of European ancestry with prostate cancer, we genotyped 36 single nucleotide polymorphisms (SNP): 35 known prostate cancer risk variants and one SNP (rs4054823) that was recently reported to be associated with prostate cancer aggressiveness. The majority of subjects had a diagnosis of prostate cancer between 1995 and 2004, and the cohort included a total of 580 prostate cancer-specific deaths. We evaluated associations between the 36 polymorphisms and prostate cancer survival, as well as other clinical parameters including age at diagnosis, prostate-specific antigen (PSA) at diagnosis, and Gleason score. Two SNPs, rs2735839 at chromosome 19q13 and rs7679673 at 4q24, were associated with prostate cancer-specific survival (P = 7 × 10(-4) and 0.014, respectively). A total of 12 SNPs were associated with other variables (P < 0.05): age at diagnosis, PSA at diagnosis, Gleason score, and/or disease aggressiveness based on D'Amico criteria. Genotype status at rs4054823 was not associated with aggressiveness or outcome. Our results identify two common polymorphisms associated with prostate cancer-specific mortality.

The risk of renal impairment in hormone-refractory prostate cancer patients with bone metastases treated with zoledronic acid.

BACKGROUND: Bisphosphonates have been used to treat bone metastases in hormone-refractory prostate cancer (HRPC), but certain agents have been associated with renal toxicity. For this observational study, the authors assessed the risk of renal impairment in patients with HRPC who received zoledronic acid from December 1999 to April 2005. METHODS: A comprehensive medical records review was performed in a major tertiary oncology center (n = 122 patients). The primary outcome of renal impairment was defined as an increase >or=0.5 mg/dL or >or=1.0 mg/dL over baseline creatinine value if the baseline value was <1.4 mg/dL or >or=1.4 mg/dL, respectively. A risk factor analysis was conducted using the Andersen-Gill extension to the Cox proportional hazards model. RESULTS: Renal impairment was observed in 23.8% of patients. The risk of renal impairment increased with an extended duration of zoledronic acid therapy (<6 months, 11.1%; >or=24 months, 26.3%) and previous pamidronate treatment (45.5% vs 19.0% for patients with no prior pamidronate). A significantly greater risk of renal impairment was associated with increasing age at zoledronic acid initiation, prior pamidronate use, and a history of renal disease, hypertension, or smoking (P

Development of an integrated prostate cancer research information system.

BACKGROUND: In this article, we describe the design and implementation of a comprehensive prostate cancer database developed to collect, store, and access clinical, treatment, and outcomes data for research and clinical care. PATIENTS AND METHODS: The Prostate Cancer Clinical Research Information System is a relational database. Data are entered from multiple sources, including medical records, institutional laboratory, patient registration, pharmacy systems, and clinician forms. The history, design, and operational characteristics of the database are described. Issues regarding necessary staffing and funding of databases are reviewed. RESULTS: Four thousand two hundred forty-six patients have information in the Prostate Cancer Clinical Research Information System. Mean age of patients is 62 years, and 89% are white. Seventy-one percent of patients presented at diagnosis with T1 or T2 disease, and 78% had biopsy Gleason scores of