Nadir PSA level and time to PSA nadir following primary androgen deprivation therapy are the early survival predictors for prostate cancer patients with bone metastasis

Predictive clinical indicators of biochemical progression in advanced prostate cancer patients receiving Leuplin depot as androgen deprivation therapy

Therapeutic planning and counseling for advanced prostate cancer patients receiving androgen deprivation therapy (ADT) is complicated because the prognoses are highly variable. The purpose of this study is to identify predictive clinical indicators of biochemical progression (BCP). In this retrospective analysis, data from 107 newly diagnosed patients (from November 1995 to April 2008) with advanced prostate adenocarcinoma receiving Leuprorelin acetate depot were analyzed. Data was collected from the computerized registry of two collaborating medical centers in Taiwan. Cox regression and Kaplan-Meier analyses were used to evaluate the relationship between potential predictive parameters and BCP. Univariate analysis revealed that predictors of BCP included (1) initial serum prostate-specific antigen (PSA) (hazard ratio [HR], 1.00; 95% confidence interval [CI] 1.00–1.00); (2) log of initial PSA (HR, 1.35; 95% CI 1.17–1.56); (3) PSA density at diagnosis (HR, 1.00; 95% CI 1.00–1.01), and (4) pathological bone fracture (HR, 2.22; 95% CI 1.20–4.11). Age (HR, 0.94; 95% CI 0.91–0.98) and hemoglobin levels (HR, 0.86; 95% CI 0.76–0.97) were also associated with greater risk of BCP. After adjusting for age, pathologic fracture, and hemoglobin level, the initial PSA and PSA density were no longer significantly associated with BCP. However, age and hemoglobin levels continued to be associated with greater risk of BCP (P≤0.007). Using Kaplan-Meier analysis, patients with higher initial PSA concentration, pathological bone fracture, and low hemoglobin had a greater probability of BCP. Thus, low hemoglobin and age are predictive indicators of BCP and therefore early indicators of BCP despite ADT therapy.

Nadir PSA level and time to nadir PSA are prognostic factors in patients with metastatic prostate cancer

Background

Primary androgen deprivation therapy (PADT) is the most effective systemic therapy for patients with metastatic prostate cancer. Nevertheless, once PSA progression develops, the prognosis is serious and mortal. We sought to identify factors that predicted the prognosis in a series of patients with metastatic prostate cancer.

Methods

Two-hundred eighty-six metastatic prostate cancer patients who received PADT from 1998 to 2005 in Nara Uro-Oncology Research Group were enrolled. The log-rank test and Cox’s proportional hazards model were used to determine the predictive factors for prognosis; rate of castration-resistant prostate cancer (CRPC) and overall survival.

Results

The median age, follow-up period and PSA level at diagnosis were 73 years, 47 months and 174 ng/mL, respectively. The 5-year overall survival rate was 63.0%. The multivariable analysis showed that Gleason score (Hazard ratio [HR]:1.362; 95% confidence interval [C.I.], 1.023-1.813), nadir PSA (HR:6.332; 95% C.I., 4.006-9.861) and time from PADT to nadir (HR:4.408; 95% C.I., 3.099-6.271) were independent prognostic factors of the incidence of CRPC. The independent parameters in the multivariate analysis that predicted overall survival were nadir PSA (HR:5.221; 95% C.I., 2.757-9.889) and time from PADT to nadir (HR:4.008; 95% C.I., 2.137-7.517).

Conclusions

Nadir PSA and time from PADT to nadir were factors that affect both CRPC and overall survival in a cohort of patients with metastatic prostate cancer. Lower nadir PSA level and longer time from PADT to nadir were good for survival and progression.

The utility of prostate-specific antigen in the management of advanced prostate cancer

To review current prostate-specific antigen (PSA) metrics used in monitoring treatment of advanced prostate cancer, with a specific focus on castration-resistant prostate cancer (CRPC) therapies. Explore what is known about the correlation between PSA and androgen levels as well as underlying reasons for persistent PSA expression and serum elevation in CRPC, and outline suggestions for use of PSA in managing patients with advanced prostate cancer. A comprehensive search of the PubMed database for English language articles through April 2012 was performed using the following Medical Subject Headings (MeSH) keywords or terms, alone or in combination: 'prostate cancer'; 'prostate cancer treatment'; 'prostate cancer outcomes'; 'prostate-specific antigen'; 'androgen receptor'; 'advanced prostate cancer'; 'castration-resistant prostate cancer'; 'biomarkers'. Bibliographies of relevant articles were searched for additional references. Relevant medical society and regulatory agency web sites from the USA and Europe were accessed for issued guidance on PSA use. PSA doubling time (PSADT) is a useful metric for determining which patients should be considered for androgen-deprivation therapy (ADT) after failing local treatment or for second-line therapies after failing ADT. However, it is not a validated surrogate for survival and no therapy has received regulatory approval based upon PSADT characteristics. PSA nadir and time-to-nadir have been identified as possible prognostic markers for patients receiving ADT. There is no universally accepted definition for PSA progression, nor is PSA progression a regulatory-approved surrogate for clinical progression in drug approval trials. PSA responses to second-line therapies can vary and are not considered by regulatory agencies as valid surrogates for clinical endpoints, so they must be assessed in the context of each individual therapy and trial design. PSA expression in CRPC is often a reflection of persistent androgen receptor activity. While we can provide guidance for use of PSA monitoring in managing patients with advanced prostate cancer based on the data at hand, there is an urgent need for prospective analyses of refined PSA metrics in conjunction with newer prostate cancer biomarkers in clinical trials to provide stronger evidence for their roles as surrogate endpoints.

Cutoff value of time to prostate-specific antigen nadir is inversely correlated with disease progression in advanced prostate cancer

To identify the early predictor of progression to castration-resistant prostate cancer (CRPC) for different stage of advanced PC patients, we focused on time to prostate-specific antigen (PSA) nadir following primary androgen deprivation therapy (PADT). We reviewed 184 advanced (locally advanced and metastatic) PC patients (101 patients with bone metastasis (BM) and 83 patients without BM at presentation) who had received PADT at our institution. We evaluated laboratory data, pathological results, and the influence of PSA kinetics impact on disease progression. The progression rates were analyzed with reference to the nadir PSA level and time to PSA nadir (TTN) following PADT by Kaplan-Meier method. In all, 103 patients (56%) progressed to CRPC. Nadir PSA lower than 0.2 ng/ml (nadir ≤0.2) during PADT was observed in 114 patients (62%). Median TTN was 8.5 months in patients with BM and 11.5 months in patients without BM. Multivariate analysis revealed that nadir ≤0.2 following PADT (P<0.001), longer TTN (>8 months) (P<0.001), extent of disease on bone scan grade (P=0.02), and T stage (P=0.04) in BM group and nadir ≤0.2 following PADT (P<0.001), longer TTN (>11 months) (P<0.001), and T stage (P=0.03) in without BM group were independent prognostic factors for progression. In both groups, longer TTN identified patients with prolonged progression-free survival in both nadir ≤0.2 and >0.2 nadir levels. Longer TTN is strongly associated with a low risk of disease progression, and the cutoff value of TTN could be inversely correlated with disease progression.

Prostate-specific antigen nadir and time to prostate-specific antigen nadir following maximal androgen blockade independently predict prognosis in patients with metastatic prostate cancer

Purpose

To evaluate the influence of prostate-specific antigen (PSA) kinetics following maximal androgen blockade (MAB) on disease progression and cancer-specific survival in patients with metastatic, hormone-sensitive prostate cancer.

Materials and Methods

One hundred thirty-one patients with metastatic, hormone-sensitive prostate cancer treated with MAB at our institution were included in this study. Patients' characteristics, PSA at MAB initiation, PSA nadir, time to PSA nadir (TTN), and PSA decline were analyzed by using univariate and multivariate analysis.

Results

At a median follow-up of 30 months, 97 patients (74.0%) showed disease progression and 65 patients (49.6%) died. Fifty-nine patients (45.0%) died from prostate cancer. In the univariate analysis, PSA at MAB initiation, PSA nadir, TTN, and PSA decline were significant predictors of progression-free survival. Also, PSA nadir, TTN, and PSA decline were significant predictors of cancer-specific survival. In the multivariate analysis, higher PSA nadir (≥0.2 ng/ml) and shorter TTN (<8 months) were independent predictors of shorter progression-free and cancer-specific survival. In the combined analysis of PSA nadir and TTN, patients with higher PSA nadir and shorter TTN had the worst progression-free survival (hazard ratio [HR], 14.098; p<0.001) and cancer-specific survival (HR, 14.050; p<0.001) compared with those with lower PSA nadir and longer TTN.

Conclusions

Our results suggest that higher PSA nadir level and shorter TTN following MAB are associated with higher risk of disease progression and poorer survival in patients with metastatic, hormone-sensitive prostate cancer. Furthermore, these two variables have a synergistic effect on the outcome.

Predicting response to hormonal therapy and survival in men with hormone sensitive metastatic prostate cancer

Androgen deprivation is the cornerstone of the management of metastatic prostate cancer. Despite several decades of clinical experience with this therapy there are no standard predictive biomarkers for response. Although several candidate genetic, hormonal, inflammatory, biochemical, metabolic biomarkers have been suggested as potential predictors of response and outcome, none has been prospectively validated nor has proven clinical utility to date. There is significant heterogeneity in the depth and duration of hormonal response and in the natural history of advanced disease; therefore to better optimize/individualize therapy and for future development, identification of biomarkers is critical. This review summarizes the current data on the role of several candidate biomarkers that have been evaluated in the advanced/metastatic disease setting.

Clinical features and prognostic factors for patients with bone metastases from prostate cancer

To identify the clinical features and independent predictors of survival in patients with bone metastases from prostate cancer (PCa). We retrospectively analysed 115 PCa patients with bone metastases between 1997 and 2009. The overall survival rate after bone metastases was calculated using the Kaplan-Meier method. The prognostic factors were identified by univariate analysis using a log-rank test and by multivariate analysis using Cox proportional hazards regression models. The follow-up rate was 100%, the follow-up cases during 1, 3 and 5 years were 103, 79 and 55, respectively. The 1-, 3- and 5-year survival rates were 89.1%, 60.9% and 49.8%, respectively, with a median survival time of 48.5 months for patients with bone metastases from PCa. In univariate analysis, age, Gleason score, clinical stage, the number of bone lesions, alkaline phosphatase (ALP) level, invasion of neighbouring organs and non-regional lymph node metastases were correlated with prognosis. By multivariate analysis using Cox regression, ALP level, Gleason score and non-regional lymph node metastases were independent prognostic factors. These prognostic factors will help us to determine the appropriate dose and fraction of radiotherapy for these patients.