Age-Adapted Prostate Cancer Gene 3 Score Interpretation - Suggestions for Clinical Use.

BACKGROUND: The prostate cancer antigen 3 (PCA3) gene urine assay is established for biopsy decision in case of prostate cancer (PC) suspicion. Recent findings pointed to an age dependence of PCA3, with putative impact on test interpretation. However, to date no experience has been reported with regard to the extent age might modify the score in certain age ranges. Therefore, the aim of the present study was to re-evaluate the age dependency and, moreover, give suggestions for interpretation of the PCA3 score in dependence of patient's age in daily routine. METHODS: The study comprised 684 patients before prostate biopsy or prostatectomy. Post-massage voided urine samples were assessed by PCA3 measurement. PCA3 scores were correlated to patient's age. The collective was divided into four subcollectives by quartiles of age distribution. For every subcollective the cutoff value at specificity of ≥ 60 was determined. Results were classified by age-class specific cutoff values and test qualities were compared at different cutoffs. RESULTS: In the collective, 59.1% of patients had a positive biopsy. PCA3 correlated to patient's age in univariate and multivariate analysis (p < 0.001 each). The division into age subcollectives revealed groups < 60, 60 - 65, 66 - 69 and > 69 years. Median PCA3 values of patients without/with PC were 17/32, 27/42, 34/55 and 52/68 in the four age classes. Cutoff values for which specificity was determined with ≥ 60 were 23, 39, 42, and 65. Constant cutoff values showed lower sensitivities in younger and lower specificities in older patients. Only the age adjusted values revealed an improved performance with PPV 68.7, accuracy 59.5 and sensitivity 57.7 at specificity of 62.1% in the whole cohort. CONCLUSIONS: The study confirms that the PCA3 score increases with age. The recommended cutoff score of 35 is suitable especially for patients aged in their sixties. Lower reference values between 20 and 30 have to be taken into account in patients aged < 60 years and higher values around 40 to 50 may point to suspicion for PC in patients > 69 years. These results may further improve the diagnostic performance of the PCA3 test and keep the PCA3 test as a significant test in PC diagnostics along with new upcoming urine markers.

Assessment of a new point-of-care system for detection of prostate specific antigen.

BACKGROUND: Measurement of the prostate specific antigen (PSA) remains an important tool in prostate cancer (PC) diagnosis. Due to limited availability of laboratory devices in an outpatient setting, compact and easy-to-handle point-of-care (POC) systems are desirable. Recently, a chip for PSA measurement on the concile® Ω100 POC reader platform was introduced. To investigate the clinical applicability, we evaluated the system in a consecutive cohort of patients undergoing PSA measurement in our outpatient clinic. METHODS: Between 07/2014 and 01/2015, PSA was analyzed in a total of 198 patients by the POC reader system and in parallel by an Immulite 2000® and Centaur® standard laboratory system, respectively. By standard (Immulite®) measurement, 67 (34,2 %) had PSA > 4 ng/ml and 131 (65,8 %) had PSA ≤ 4 ng/ml. Results were correlated by linear regression analyses for all patients and within PSA subgroups. For patients with available prostate histology after PSA measurement (n = 68), receiver-operating characteristic curves were created and area under the curve (AUC), sensitivity and specificity for the prediction of PC at best cut-off value were calculated. RESULTS: The coefficients of determination (r(2)) for the POC device compared to laboratory testing were 0.72 (Immulite®) and 0.63 (Centaur®), respectively (both p < 0.0001). In the PSA range of ≤4 ng/ml, the observed correlations were 0.75 and 0.70, respectively. For the POC test system, AUC for detection of PC was calculated with 0.745 while the standard laboratory tests showed 0.778 (Immulite®) and 0.771 (Centaur®). At best cut-off of 3.64 ng/ml, PSA analysis by the POC system showed a sensitivity of 85.7 % and a specificity of 66.7 %. CONCLUSIONS: The POC system obtained good concordance to elaborate laboratory measurement. In a screening scenario, the system provides quick and reliable PSA measurement, especially in the PSA range up to 4 ng/ml.

Serum receptor activator of nuclear factor κB ligand (RANKL) levels predict biochemical recurrence in patients undergoing radical prostatectomy.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: There is increasing evidence that the receptor activator of nuclear factor κB ligand (RANKL) pathway not only contributes to the development of bone metastases, but also influences tumour biology in earlier stages of cancer. The study shows that preoperative serum levels of RANKL and its inhibitor osteoprotegerin (OPG) have a prognostic impact in patients undergoing radical prostatectomy for clinically localized prostate cancer. Both high levels of RANKL and a higher RANKL/OPG ratio are independent predictors of early biochemical recurrence in these patients. OBJECTIVE: To assess the prognostic impact of proteins of the receptor activator of nuclear factor κB (RANKL) pathway in serum samples from patients undergoing radical prostatectomy. PATIENTS AND METHODS: We retrospectively determined soluble RANKL (sRANKL) and osteoprotegerin (OPG) by ELISA in serum samples of 178 patients undergoing radical prostatectomy between 2004 and 2006. Clinical and patient follow-up data were analysed using the Wilcoxon-Mann-Whitney test, the Kaplan-Maier method, and single variable or multifactorial Cox proportional hazards analysis. RESULTS: Higher serum sRANKL levels (P = 0.01), lower serum OPG levels (P = 0.01) and a higher sRANKL/OPG ratio (P = 0.004) were significant risk factors for biochemical recurrence (BCR). In multifactorial analysis, adjusted for the common risk factors for BCR, sRANKL and sRANKL/OPG ratio were confirmed as independent prognostic factors. Neither sRANKL nor OPG showed a clear association with histopathological factors such as pT stage, pN Gleason score or resection margin status, nor were they associated with prostate-specific antigen level. CONCLUSIONS: Greater activity of the RANKL pathway in the serum of patients with prostate cancer undergoing radical prostatectomy is a risk factor for BCR. The RANKL pathway seems to contribute to the biological behaviour of prostate cancer even at the organ-confined stage of the disease.

Alterations of the RANKL pathway in blood and bone marrow samples of prostate cancer patients without bone metastases.

OBJECTIVES: The receptor activator of the NF-kB ligand (RANKL) pathway is a key mediator of prostate cancer (PC)-induced bone disease. However, little is known about this pathway in patients with non-metastatic PC. We aimed to investigate whether changes of RANKL, its inhibitor osteoprotegerin (OPG) and bone marrow-mesenchymal stromal cells (BM-MSCs) occur in PC patients without manifest bone metastases. PATIENTS AND METHODS: We determined OPG and soluble RANKL (sRANKL) in serum and corresponding bone marrow (BM) samples of 140 patients before radical prostatectomy by enzyme-linked immunosorbent assay (ELISA). As control serum samples of 50 patients with benign prostate hyperplasia were analyzed. BM mononuclear cells (BMNCs) of 16 PC patients were analyzed for expression of RANKL and CD271 (as marker for MSCs) by flow cytometry. RESULTS: PC patients had significantly lower serum levels of OPG compared to BPH patients (P = 0.007), whereas no differences were observed for serum sRANKL (P = 0.74). Both OPG and sRANKL concentrations of serum and corresponding BM samples correlated significantly (P < 0.0001 each). Interestingly, in PC patients, lower serum and BM OPG levels were associated with a higher proportion of BM-MSCs (P = 0.04 and 0.0016, respectively). No correlations were observed for sRANKL, OPG, BM-MSCs, and established risk parameters of PC. DISCUSSION: The results of the study indicate that localized PC is associated with early specific changes of the RANKL pathway in serum and bone marrow (BM). These changes might be part of the pre-metastatic niche of PC and implicate a potential benefit of RANKL inhibition in patients with localized PC.

Systemic Alterations of Wnt Inhibitors in Patients with Prostate Cancer and Bone Metastases.

PURPOSE: Dickkopf-1 (DKK-1) and sclerostin seem to inhibit osteoblast activity by blocking the Wnt pathway, which leads to progression of metastatic prostate cancer (PC). However, it is unknown whether serum levels of these proteins are altered in PC patients with or without metastasis. The aim of this study was to assess DKK-1 and sclerostin serum levels in PC patients, including patients with bone metastases. METHODS: The study cohort (N = 143) consisted of 53 controls with benign prostatic hyperplasia (BPH), 43 with localized PC (PC cM0), and 47 had PC with metastasis (PC cM1). Serum levels of DKK-1 and sclerostin were measured by enzyme-linked immunosorbent assay. Results were compared using the Kruskal-Wallis tests; post hoc analysis was performed using the Tukey-Kramer test. RESULTS: Mean DKK-1 levels in patients with BPH (2809.4 pg/ml) (p < 0.001) as well as PC cM1 (2575.5 pg/ml) (p = 0.001) were significantly higher than in patients with PC cN0 cM0 (1551.8 pg/ml). Among PC cM1 patients, median DKK-1 levels were significantly lower in patients with castration-resistant disease compared to those with hormone-sensitive PC (p = 0.02); in contrast, sclerostin concentrations were elevated (p = 0.04). DKK-1 correlated with PSA in the cM1 group (p = 0.03) and sclerostin correlated with PSA in the PC group (0.01). CONCLUSIONS: DKK-1 is involved in the progression of PC. DKK-1-mediated inhibition of osteoblasts, which contributes to tumor progression and osteolytic metastases, may also play a role in the development of metastases with osteoblastic features. The use of DKK-1 antibodies should be considered for studies including metastatic PC patients.

Evaluation of a new quantitative point-of-care test platform for urine-based detection of bladder cancer.

OBJECTIVE: Several commercial point-of-care (POC) tests are available for urine-based detection of bladder cancer (BC). However, these tests are restricted to dichotomized results (positive or negative), which limits their diagnostic value. Quantitative protein-based tests offer improved risk stratification but require complex methods restricted to specialized centers. Recently, the first quantitative POC system based on the detection of cytokeratin fragments became available. The aim of the study was to evaluate the diagnostic accuracy of this quantitative POC test. PATIENTS AND METHODS: A total of 198 patients having symptoms suspicious for BC were included. All patients received urethrocystoscopy and upper-tract imaging. Urine samples were analyzed by the urine BC antigen (UBC) rapid POC system and evaluated both visually and quantitatively using the concile Omega 100 POC reader. For visual evaluation, different thresholds of band intensity for considering a test positive were applied. Moreover, the UBC enzyme-linked immunosorbent assay (ELISA), urine cytology, and the nuclear matrix protein 22 BladderChek were performed. Sensitivities and specifities were calculated by contingency analyses. Optimal cutoffs of quantitative tests were determined by receiver operating characteristic curves. RESULTS: A total of 61 patients (30.8%) were diagnosed with BC. Visual evaluation of the UBC revealed sensitivities of 38.1% to 71.4% with corresponding specificities of 54.1% to 89.1%, dependent on the threshold of band intensity applied. The quantitative UBC rapid showed a sensitivity of 60.7% and a specificity of 70.1% at optimal cutoff (area under the curve = 0.68). A constant increase of both the probability of BC and high-risk BC with increasing UBC rapid values was observed. UBC concentrations determined by the reader significantly correlated with the UBC ELISA (P<0.001). The UBC ELISA, the nuclear matrix protein22 BladderChek and cytology showed sensitivities of 48.3%, 16.4%, and 51.7% with specificities of 71.3%, 95.3%, and 78.1%, respectively. CONCLUSION: The UBC rapid in combination with a quantitative POC-reader system for the first time enables quantitative determination of a BC marker under POC conditions. Diagnostic accuracy is at least equivalent to elaborate ELISA-based measurement. The quantitative use of the UBC rapid test facilitates risk prediction compared with conventional nonquantitative dichotomized POC testing.