Optimising preoperative risk stratification tools for prostate cancer using mpMRI.

PURPOSE: To improve preoperative risk stratification for prostate cancer (PCa) by incorporating multiparametric MRI (mpMRI) features into risk stratification tools for PCa, CAPRA and D'Amico. METHODS: 807 consecutive patients operated on by robot-assisted radical prostatectomy at our institution during the period 2010-2015 were followed to identify biochemical recurrence (BCR). 591 patients were eligible for final analysis. We employed stepwise backward likelihood methodology and penalised Cox cross-validation to identify the most significant predictors of BCR including mpMRI features. mpMRI features were then integrated into image-adjusted (IA) risk prediction models and the two risk prediction tools were then evaluated both with and without image adjustment using receiver operating characteristics, survival and decision curve analyses. RESULTS: 37 patients suffered BCR. Apparent diffusion coefficient (ADC) and radiological extraprostatic extension (rEPE) from mpMRI were both significant predictors of BCR. Both IA prediction models reallocated more than 20% of intermediate-risk patients to the low-risk group, reducing their estimated cumulative BCR risk from approximately 5% to 1.1%. Both IA models showed improved prognostic performance with a better separation of the survival curves. CONCLUSION: Integrating ADC and rEPE from mpMRI of the prostate into risk stratification tools improves preoperative risk estimation for BCR. KEY POINTS: • MRI-derived features, ADC and EPE, improve risk stratification of biochemical recurrence. • Using mpMRI to stratify prostate cancer patients improves the differentiation between risk groups. • Using preoperative mpMRI will help urologists in selecting the most appropriate treatment.

A positive Real-Time Elastography (RTE) combined with a Prostate Cancer Gene 3 (PCA3) score above 35 convey a high probability of intermediate- or high-risk prostate cancer in patient admitted for primary prostate biopsy.

BACKGROUND: The standard of care in patients with suspected prostate cancer (PCa) is systematic prostate biopsies. This approach leads to unnecessary biopsies in patients without PCa and also to the detection of clinical insignificant PCa. Better tools are wanted. We have evaluated the performance of real-time elastography (RTE) combined with prostate cancer gene 3 (PCA3) in an initial biopsy setting with the goal of better identifying patients in need of prostate biopsies. METHODS: 127 patients were included in this study; three were excluded because of not measureable PCA3 score leading to 124 evaluable patients. A cut-off value of 35 was used for PCA3. All patients were examined with a Hitachi Preirus with an endfire probe for RTE, a maximum of five targeted biopsies were obtained from suspicious lesions detected by RTE. All patients then had a 10-core systematic biopsy performed by another urologist unaware of the RTE results. The study includes follow-up data for a minimum of three years; all available histopathological data are included in the analysis. RESULTS: There was a significant difference in PCA3 score: 26.6 for benign disease, 73.6 for cancer patients (p < 0.001). 70 patients (56 %) were diagnosed with prostate cancer in the study period, 21 (30 %) low-risk, 32 (46 %) intermediate-risk and 17 (24 %) high-risk. RTE and PCA3 were significant markers for predicting intermediate- and high-risk PCa (p = 0.001). The combination of RTE and PCA3 had a sensitivity of 96 % and a negative predictive value (NPV) of 90 % for the group of intermediate- and high-risk PCa together and a NPV for high-risk PCa of 100 %. If both parameters are positive there is a high probability of detecting intermediate- or high-risk PCa, if both parameters are negative there is only a small chance of missing prostate cancer with documented treatment benefit. CONCLUSIONS: RTE and PCA3 may be used as pre-biopsy examinations to reduce the number of prostate biopsies.

1.5-T multiparametric MRI using PI-RADS: a region by region analysis to localize the index-tumor of prostate cancer in patients undergoing prostatectomy.

BACKGROUND: The use of multiparametric magnetic resonance imaging (mpMRI) to detect and localize prostate cancer has increased in recent years. In 2010, the European Society of Urogenital Radiology (ESUR) published guidelines for mpMRI and introduced the Prostate Imaging Reporting and Data System (PI-RADS) for scoring the different parameters. PURPOSE: To evaluate the reliability and diagnostic performance of endorectal 1.5-T mpMRI using the PI-RADS to localize the index tumor of prostate cancer in patients undergoing prostatectomy. MATERIAL AND METHODS: This institutional review board IRB-approved, retrospective study included 63 patients (mean age, 60.7 years, median PSA, 8.0). Three observers read mpMRI parameters (T2W, DWI, and DCE) using the PI-RADS, which were compared with the results from whole-mount histopathology that analyzed 27 regions of interest. Inter-observer agreement was calculated as well as sensitivity, specificity, positive predictive value (PPV), and negative predicted value (NPV) by dichotomizing the PI-RADS criteria scores ≥3. A receiver-operating curve (ROC) analysis was performed for the different MR parameters and overall score. RESULTS: Inter-observer agreement on the overall score was 0.41. The overall score in the peripheral zone achieved sensitivities of 0.41, 0.60, and 0.55 with an NPV of 0.80, 0.84, and 0.83, and in the transitional zone, sensitivities of 0.26, 0.15, and 0.19 with an NPV of 0.92, 0.91, and 0.92 for Observers 1, 2, and 3, respectively. The ROC analysis showed a significantly increased area under the curve (AUC) for the overall score when compared to T2W alone for two of the three observers. CONCLUSION: 1.5 T mpMRI using the PI-RADS to localize the index tumor achieved moderate reliability and diagnostic performance.

A positive real-time elastography is an independent marker for detection of high-risk prostate cancers in the primary biopsy setting.

OBJECTIVE: To evaluate the performance of real-time elastography (RTE) in an initial biopsy setting. PATIENTS AND METHODS: In the period from February 2011 to June 2012, 127 consecutive patients were included in the study. We used a Hitachi Preirus with Hi-RTE module, a prostate end-fire transrectal probe was used for RTE and for targeted biopsies, and a simultaneous biplane probe was used for the standard systematic biopsies. The peripheral zone of the prostate was divided into six regions, and each biopsy obtained was referred to a specific region. All patients were first examined with RTE and, if cancer was suspected, targeted biopsies were taken. A standard systematic 10-core biopsy was then taken in all patients. RESULTS: In all, 64 (50%) patients were diagnosed with prostate cancer in the initial biopsy setting. Three patients were diagnosed solely on RTE-targeted biopsies, 31 were found only in systematic biopsies, and 30 were correctly diagnosed with both methods. In the RTE-positive group there was a significantly higher frequency of positive cores, a lower prostate volume, a higher Gleason score, and a higher fraction of cancer tissue in each core. In a multiple regression model RTE was an independent marker for high-risk cancer. The sensitivity of 42% for all prostate cancers increased to 60% for high-grade prostate cancers. Similarly, the negative predictive value increased from 79% to 97%. An additional eight patients were diagnosed with prostate cancer during the study period. CONCLUSIONS: A positive RTE is an independent marker for detection of high-risk prostate cancer, and a negative RTE argues against such. RTE with targeted biopsies cannot replace systematic biopsies, but provides valuable additional information about the tumours.

Microvascular proliferation is associated with high tumour blood flow by mpMRI and disease progression in primary prostate cancer.

Active angiogenesis may be assessed by immunohistochemistry using Nestin, a marker of newly formed vessels, combined with Ki67 for proliferating cells. Here, we studied microvascular proliferation by Nestin-Ki67 co-expression in prostate cancer, focusing on relations to quantitative imaging parameters from anatomically matched areas obtained by preoperative mpMRI, clinico-pathological features and prognosis. Tumour slides from 67 patients (radical prostatectomies) were stained for Nestin-Ki67. Proliferative microvessel density (pMVD) and presence of glomeruloid microvascular proliferation (GMP) were recorded. From mpMRI, forward volume transfer constant (Ktrans), reverse volume transfer constant (kep), volume of EES (ve), blood flow, and apparent diffusion coefficient (ADC) were obtained. High pMVD was associated with high blood flow (p = 0.008) and low ADC (p = 0.032). High Ktrans, kep, and blood flow were associated with high Gleason score. High pMVD, GMP, and low ADC were associated with most adverse clinico-pathological factors. Regarding prognosis, high pMVD, Ktrans, kep, and low ADC were associated with reduced biochemical recurrence-free- and metastasis-free survival (p ≤ 0.044) and high blood flow with reduced time to biochemical- and clinical recurrence (p < 0.026). In multivariate analyses however, microvascular proliferation was a stronger predictor compared with blood flow. Indirect, dynamic markers of angiogenesis from mpMRI and direct, static markers of angiogenesis from immunohistochemistry may aid in the stratification and therapy planning of prostate cancer patients.

Prosaposin inhibits tumor metastasis via paracrine and endocrine stimulation of stromal p53 and Tsp-1.

Metastatic tumors can prepare a distant site for colonization via the secretion of factors that act in a systemic manner. We hypothesized that non- or weakly metastatic human tumor cells may act in an opposite fashion by creating a microenvironment in distant tissues that is refractory to colonization. By comparing cell lines with different metastatic potential, we have identified a tumor-secreted inhibitor of metastasis, prosaposin (Psap), which functions in a paracrine and endocrine fashion by stimulating the expression of thrombospondin-1 (Tsp-1) in fibroblasts present in both primary tumors and distant organs, doing so in a p53-dependent manner. Introduction of Psap in highly metastatic cells significantly reduced the occurrence of metastases, whereas inhibition of Psap production by tumor cells was associated with increased metastatic frequency. In human prostate cancer, decreased Psap expression was significantly associated with metastatic tumors. Our findings suggest that prosaposin, or other agents that stimulate p53 activity in the tumor stroma, may be an effective therapy by inhibition of the metastatic process.

PRSS2 remodels the tumor microenvironment via repression of Tsp1 to stimulate tumor growth and progression.

The progression of cancer from localized to metastatic disease is the primary cause of morbidity and mortality. The interplay between the tumor and its microenvironment is the key driver in this process of tumor progression. In order for tumors to progress and metastasize they must reprogram the cells that make up the microenvironment to promote tumor growth and suppress endogenous defense systems, such as the immune and inflammatory response. We have previously demonstrated that stimulation of Tsp-1 in the tumor microenvironment (TME) potently inhibits tumor growth and progression. Here, we identify a novel tumor-mediated mechanism that represses the expression of Tsp-1 in the TME via secretion of the serine protease PRSS2. We demonstrate that PRSS2 represses Tsp-1, not via its enzymatic activity, but by binding to low-density lipoprotein receptor-related protein 1 (LRP1). These findings describe a hitherto undescribed activity for PRSS2 through binding to LRP1 and represent a potential therapeutic strategy to treat cancer by blocking the PRSS2-mediated repression of Tsp-1. Based on the ability of PRSS2 to reprogram the tumor microenvironment, this discovery could lead to the development of therapeutic agents that are indication agnostic.

The epithelial-mesenchymal transition regulators Twist, Slug, and Snail are associated with aggressive tumour features and poor outcome in prostate cancer patients.

The prognostic importance of transcription factors promoting epithelial-mesenchymal transition (EMT) and angiogenesis has not been well explored in prostate cancer patients with long follow-up, nor the interplay between these factors. The objective of this study was to assess the individual protein expression and co-expression of Twist, Slug (Snai2), Snail (Snai1), and hypoxia-inducible factor-1 alpha (Hif-1α) in prostate cancer in relation to EMT, angiogenesis, hypoxia, tumour features, disease recurrence, and patient survival. Immunohistochemical staining was performed on tissue microarray sections from 338 radical prostatectomies with long follow-up. In addition, 41 cases of prostatic hyperplasia, 33 non-skeletal metastases, 13 skeletal metastases, and 33 castration-resistant prostate carcinomas were included. Our findings were validated in external gene expression data sets. Twist was overexpressed in primary prostate cancer and markedly reduced in distant metastases (p < 0.0005). Strong expression of Twist and Slug was associated with Hif-1α in localised prostate cancer (p ≤ 0.001), and strong Twist was associated with Hif-1α in castration-resistant carcinomas (p = 0.044). Twist, Slug, and increased Snail at the tumour stromal border were associated with vascular factors (p ≤ 0.045). Each of the three EMT-regulating transcription factors were associated with aggressive tumour features and shorter time to recurrence and cancer-specific death. Notably, the co-expression of factors demonstrated an enhanced influence on outcome. In the subgroup of E-cadherinlow carcinomas, strong Slug was associated with shorter time to all end points and was an independent predictor of time to multiple end points, including cancer-specific death (hazard ratio 3.0, p = 0.041). To conclude, we demonstrate an important relation between EMT, hypoxia, and angiogenesis and a strong link between the investigated EMT regulators and aggressive tumour features and poor patient outcome in prostate cancer. Despite the retrospective nature of this long-term study, our findings could have a significant impact on the future treatment of prostate cancer, where tailored therapies might be directed simultaneously against epithelial-mesenchymal phenotypes, angiogenesis, and tumour hypoxia.

The expression of thrombospondin-1 and p53 in clear cell renal cell carcinoma: its relationship to angiogenesis, cell proliferation and cancer specific survival.

PURPOSE: We evaluated possible associations among thrombospondin-1, p53 expression, microvessel density, cell proliferation index, nuclear grade, tumor stage and continuously coded tumor size in clear cell renal cell carcinoma. The value of thrombospondin-1 as a prognostic marker in clear cell renal cell carcinoma was examined. MATERIALS AND METHODS: A total of 172 consecutive patients with clear cell renal cell carcinoma treated with radical nephrectomy were initially enrolled in the study. However, due to technical problems and lack of material 12 cases were excluded from analysis. A total of 68 patients (43%) died of renal cell carcinoma and 46 (29%) died of other diseases. Median followup for the surviving 42 patients (29%) was 13.8 years. The expression of thrombospondin-1, Ki-67 (proliferation index), p53 and microvessel density were analyzed without knowledge of the clinical outcome on formalin fixed, paraffin embedded tissues. RESULTS: Low expression of thrombospondin-1 was significantly associated with advanced stage (p <0.001), high nuclear grade (p = 0.001), positive p53 status (p <0.001), high proliferation index (p = 0.001), high microvessel density (p = 0.036) and tumor progression (p = 0.006). On univariate analysis thrombospondin-1, microvessel density, proliferation index, p53 over expression, TNM stage, Fuhrman nuclear grade (p <0.001) and continuously coded tumor size (p = 0.002) had a significant impact on survival. Multivariate analysis revealed TNM stage, thrombospondin-1, p53, Ki-67 (proliferation index) and microvessel density were independent predictors of cancer specific survival. CONCLUSIONS: Thrombospondin-1 expression is strongly associated with prognostic tumor features in clear cell renal cell carcinoma and is an independent prognostic factor for cancer specific survival. Our findings revealed a significant correlation among p53, proliferation index, microvessel density and thrombospondin-1 expression, and indicate that thrombospondin-1 may have an impact on angiogenesis, proliferation and tumor aggressiveness in clear cell renal cell carcinoma.

Outcome in intermediate or high risk prostate cancer patients receiving radiation dose and hormone therapy.

BACKGROUND: To analyse the impact of radiation dose escalation and hormone treatment in prostate cancer patients according to risk groups. MATERIAL AND METHODS: Totally 494 prostate cancer patients received external beam radiation therapy, with or without androgen deprivation, between January 1990 and December 1999. The patients were divided into three risk groups, where the low risk group (stage T(1c), pretreatment prostate-specific antigen (PSA) level < or =10 ng/ml and WHO Grade 1) included 26 patients, the intermediate risk group (either stage T(2), PSA 10.1-20 ng/ml or WHO Grade 2) comprised 149 patients whereas the high-risk group (either stage T(3), PSA >20 ng/ml or WHO Grade 3) included 319 patients. RESULTS: In the intermediate risk group, the 5-years bNED rate was 92%, 69% and 61% after a radiation dose of 70 Gy, 66 Gy or 64 Gy, respectively (p < 0.001). In the high-risk group, the 5-year bNED rate was 79%, 69% and 34% for the same dose levels (p < 0.001). The 5-years CSS rates were not significantly different between the dose levels in the intermediate risk group while for the high-risk group it was 93%, 92% and 80% for the three dose levels (p < 0.001). Risk group and radiation doses were independent predictors of bNED, CSS and overall survival, for bNED also hormone treatment was independent predictors. CONCLUSION: Radiation dose is important for the outcome in intermediate and high risk prostate cancer patients. A dose of 70 Gy should be considered the minimal dose for these patients.

FOXC2 expression and epithelial-mesenchymal phenotypes are associated with castration resistance, metastasis and survival in prostate cancer.

Epithelial-mesenchymal transition (EMT) is important for tumour cell invasion and metastasis and is a feature of aggressive carcinomas. EMT is characterised by reduced E-cadherin and increased N-cadherin expression (EN-switch), and increased expression of the EMT-regulating transcription factor Forkhead box protein C2 (FOXC2) has been associated with progression and poor prognosis in various malignancies. FOXC2 was recently highlighted as a novel therapy target in prostate cancer, but survival data on FOXC2 are lacking. This study evaluates the expression of FOXC2, E-cadherin and N-cadherin in different prostatic tissues focusing on EMT, clinico-pathological phenotype, recurrence and patient survival. Tissue microarray sections from 338 radical prostatectomies (1986-2007) with long and complete follow-up, 33 castration resistant prostate cancers, 33 non-skeletal metastases, 13 skeletal metastases and 41 prostatic hyperplasias were stained immunohistochemically for FOXC2, E-cadherin and N-cadherin. FOXC2 was strongly expressed in primary carcinomas, including castration resistant tumours and metastatic lesions as compared to benign prostatic hyperplasia. A hybrid epithelial-mesenchymal phenotype, with co-expression of E-cadherin and N-cadherin, was found in the majority of skeletal metastases and in a substantial proportion of castration resistant tumours. In localised carcinomas, the EN-switch was associated with adverse clinico-pathological variables, such as extra-prostatic extension, high pathological stage and lymph node infiltration. In univariate survival analyses of the clinically important, large subgroup of 199 patients with Gleason score 7, high FOXC2 expression and EN-switching were significantly associated with shorter time to clinical recurrence, skeletal metastases and cancer specific death. In multivariate Cox' survival analysis, high FOXC2 and the EN-switch, together with Gleason grade group (GG3 versus GG2), were independent predictors of time to these end-points. High FOXC2 gene expression (mRNA) was also related to patient outcome, validating our immunohistochemical findings. FOXC2 and factors signifying EMT or its intermediate states may prove important as biomarkers for aggressive disease and are potential novel therapy targets in prostate cancer.

A switch from E-cadherin to N-cadherin expression indicates epithelial to mesenchymal transition and is of strong and independent importance for the progress of prostate cancer.

PURPOSE: Cell adhesion molecules are of crucial importance in cancer invasion and metastasis. Epithelial to mesenchymal transition, characterized by reduced E-cadherin and increased N-cadherin expression, has been recognized as a feature of aggressive tumors, but the importance of this phenotype has not been settled in human prostate cancer. We here present novel data, with special focus on the independent relationship between an E-cadherin to N-cadherin switch (EN-switch) and patient prognosis. EXPERIMENTAL DESIGN: Tissue microarray sections from a consecutive series of 104 radical prostatectomies during 1988 to 1994 with detailed clinicopathologic data and long follow-up were studied immunohistochemically for the expression of E-cadherin, N-cadherin, P-cadherin, beta-catenin, and p120(CTN). RESULTS: Low E-cadherin expression was significantly associated with adverse clinicopathologic features, whereas other biomarkers were mostly related to Gleason score. In univariate survival analyses, cadherin switching (high N-cadherin and low E-cadherin) showed strong and significant associations with multiple end points of progression and cancer-specific death. Expression of the "basal cell marker" P-cadherin was associated with shorter time to skeletal metastasis (P = 0.036). In multivariate analysis of time to clinical recurrence, the "EN-switch" (hazard ratio, 4.3; P < 0.0005) had strong and independent prognostic effect, together with Gleason score. CONCLUSION: These novel data unravel the importance of epithelial to mesenchymal transition for prostate cancer progression, and demonstration of a switch from E-cadherin to N-cadherin expression could have significant effect on the care of prostate cancer patients.

Increased expression of SIM2-s protein is a novel marker of aggressive prostate cancer.

PURPOSE: The human SIM2 gene is located within the Down's syndrome critical region of chromosome 21 and encodes transcription factors involved in brain development and neuronal differentiation. SIM2 has been assigned a possible role in the pathogenesis of solid tumors, and the SIM2-short isoform (SIM2-s) was recently proposed as a molecular target for cancer therapy. We previously reported SIM2 among the highly up-regulated genes in 29 prostate cancers, and the purpose of our present study was to examine the expression status of SIM2 at the transcriptional and protein level as related to outcome in prostate cancer. EXPERIMENTAL DESIGN: By quantitative PCR, mRNA in situ hybridization, and immunohistochemistry, we evaluated the expression and significance of SIM2 isoforms in 39 patients with clinically localized prostate cancer and validated the expression of SIM2-s protein in an independent cohort of 103 radical prostatectomies from patients with long and complete follow-up. RESULTS: The SIM2 isoforms (SIM2-s and SIM2-l) were significantly coexpressed and increased in prostate cancer. Tumor cell expression of SIM2-s protein was associated with adverse clinicopathologic factors like increased preoperative serum prostate-specific antigen, high histologic grade, invasive tumor growth with extra-prostatic extension, and increased tumor cell proliferation by Ki-67 expression. SIM2-s protein expression was significantly associated with reduced cancer-specific survival in multivariate analyses. CONCLUSIONS: These novel findings indicate for the first time that SIM2 expression might be important for clinical progress of human cancer and support the recent proposal of SIM2-s as a candidate for targeted therapy in prostate cancer.

The prognostic relevance of interactions between venous invasion, lymph node involvement and distant metastases in renal cell carcinoma after radical nephrectomy.

BACKGROUND: To investigate a possible prognostic significance of interactions between lymph node invasion (LNI), synchronous distant metastases (SDM), and venous invasion (VI) adjusted for mode of detection, Eastern Cooperative Oncology Group performance status (ECOG PS), erythrocyte sedimentation rate (ESR) and tumour size (TS) in 196 patients with renal cell carcinoma treated with radical nephrectomy. METHODS: Median follow-up was 5.5 years (mean 6.9 years; range 0.01-19.4). The mode of detection, ECOG PS, ESR and TS were obtained from the patients' records. Vena cava invasion and distant metastases were detected by preoperative imaging. The surgical specimens were examined for pathological stage, LNI and VI. RESULTS: The univariate analyses showed significant impact of VI, LNI, SDM, ESR and TS (p < 0.001), as well as mode of detection (p = 0.003) and ECOG PS (p = 0.002) on cancer specific survival. In multivariate analyses LNI was significantly associated with survival only in patients without SDM or VI (p < 0.001) with a hazard ratio of 9.0. LNI lost its prognostic significance when SDM or VI was present. CONCLUSION: Our findings underline the prognostic importance of the status of the lymph nodes. LNI, SDM, ESR, and VI were independently associated with cancer specific survival after radical nephrectomy. LNI provided the strongest prognostic information for patients without SDM or VI whereas SDM and VI had strongest impact on survival when there was no nodal involvement.

ERG upregulation and related ETS transcription factors in prostate cancer.

The aim of this study was to identify and validate differentially expressed genes in matched pairs of benign and malignant prostate tissue. Samples included 29 histologically verified primary tumors and 23 benign controls. Microarray analysis was initially performed using a sequence verified set of 40,000 human cDNA clones. Among the genes most consistently and highly upregulated in prostate cancer was the ETS family transcription factor ERG (ETS related gene). This finding was validated in an expanded patient series (37 tumors and 38 benign samples) using DNA oligonucleotide microarray and real-time quantitative PCR assays. ERG was 20- to more than 100-fold overexpressed in prostate cancer compared with benign prostate tissue in more than 50% of patients according to quantitative PCR. Surprisingly, ERG mRNA levels were found to be significantly higher in the endothelial cell line, HUVEC, than in the prostate cell lines PC3, DU145 and LNCaP. In situ hybridization of prostate cancer tissue revealed that ERG was abundantly expressed in both prostate cancer cells and associated endothelial cells. The consistency and magnitude of ERG overexpression in prostate cancer appeared unique, but several related ETS transcription factors were also overexpressed in matched pairs of tumor and benign samples, whereas ETS2 was significantly underexpressed. Our findings support the hypothesis that ERG overexpression and related ETS transcription factors are important for early prostate carcinogenesis.

Expression of bFGF/FGFR-1 and vascular proliferation related to clinicopathologic features and tumor progress in localized prostate cancer.

Microvessel density (MVD) has been associated with progression of prostate cancer. Although basic fibroblast growth factor (bFGF) is a known endothelial mitogen, the prognostic role of bFGF and its receptor FGFR-1 in prostate cancer has been controversial. The aim of our study was to examine the tissue distribution and prognostic significance of bFGF, FGFR-1, and microvascular proliferation. Sections from 104 radical prostatectomy specimens were examined by factor VIII/Ki-67 staining for proliferating capillary index (PCI) and MVD, and tissue microarray sections were immunostained for bFGF and FGFR-1. Increased PCI (median 0.49%) was related to strong stromal expression of bFGF (P=0.003) but was without prognostic impact. Strong bFGF staining was associated with well-differentiated tumors, no capsular penetration, low serum-prostate-specific antigen (s-PSA), low tumor cell proliferation, and increased time to biochemical failure (P=0.007), and was of independent prognostic importance in multivariate survival analysis. bFGF expression in vessels was associated with low MVD (P=0.0003). In contrast, strong tumor cell FGFR-1 expression was related to high preoperative s-PSA. Thus, increased stromal and vessel bFGF was associated with less aggressive tumors. Our findings indicate a complex relationship between bFGF/FGFR-1 expression and prognosis of prostate cancer. Vascular proliferation revealed no prognostic impact in this study.

Prognostic importance of glomeruloid microvascular proliferation indicates an aggressive angiogenic phenotype in human cancers.

We evaluated the presence of glomeruloid microvascular proliferations (GMPs) in 723 patients with melanomas, breast, endometrial, or prostate cancer. Presence of GMPs was associated with markers of aggressive tumor behavior and significantly reduced survival or increased clinical recurrences in all four of the cancer types in univariate analysis. GMPs were related to increased microvessel density in prostate cancer only. In the case of melanomas, breast, and prostate cancers (but not endometrial cancers), GMPs were a significant prognostic factor in the final multivariate models (P all

Gene expression profiles in prostate cancer: association with patient subgroups and tumour differentiation.

Prostate carcinoma is the most common cancer of western men and is a markedly heterogeneous disease. The aim of this study was to identify signatures of differentially expressed genes in prostate cancer using DNA microarray technology, evaluating expression profiles in matched pairs of benign and malignant tissue. Samples were collected from 33 radical prostatectomies, and 52 specimens were included, representing 29 histologically verified primary tumours, 19 paired samples of malignant and benign tissue, and 4 non-paired benign tissue samples. Microarray analysis was performed using an expanded sequence verified set of 40,000 human cDNA clones, revealing several genes with significant differences between malignant and benign tissue, including recently reported genes like alpha-methylacyl-CoA racemase (AMACR) and hepsin, as well as genes relevant for tumour development and progression. Leave out cross validation (LOCV) test correctly predicted tumour or benign tissue in 47 (90.3%) out of 52 cases, significantly better than cross validation tests using randomly permuted tissue labels. Unsupervised clustering analysis revealed 3 distinct patient clusters significantly associated with Gleason score, and high grade tumours (Gleason score >/=7) accumulated in cluster 1 (C1). Gene expression profiles correctly predicted 100% of tumour samples segregating to C1, as also validated by LOCV. Gene expression profiles were analysed in filtered and floored datasets with similar results, and a pair-wise design was also tested. Gene expression profiles provided tumour clusters linked to differentiation, and revealed novel markers relevant for molecular classification, grading and therapy of prostate cancer.

Combined loss of PTEN and p27 expression is associated with tumor cell proliferation by Ki-67 and increased risk of recurrent disease in localized prostate cancer.

PURPOSE: Recent experimental work indicates a major role for PTEN and p27 in prostate cancer. The combined loss of PTEN and p27 was found to strongly increase the development of prostatic carcinomas in an animal model, and a prognostic value in human tumors was postulated. The purpose of our study was to examine the impact of PTEN and p27 on prognosis in a series of prostate cancer patients, using high-density tissue microarray technology for expression profile analysis of PTEN, p27, and tumor cell proliferation. EXPERIMENTAL DESIGN: The expression of PTEN and p27 was examined in primary prostatic carcinomas from 104 patients treated with radical prostatectomy and with complete follow-up available. Using high-throughput tissue microarrays, the expression of PTEN and p27 was examined by immunohistochemistry, and the results were related to clinicopathological variables, tumor cell proliferation (Ki-67), and time to disease progression. RESULTS: PTEN was negative in 28 of 103 tumors (27.2%), and median p27 expression was 64%. Combined loss of PTEN and p27 expression defined a group of 18 tumors (17.5%) associated with increased tumor diameter, seminal vesicle invasion, increased pathological stage, and elevated tumor cell proliferation by Ki-67. Cox regression analysis revealed that loss of PTEN/p27 expression and histological grade were both independent predictors of time to biochemical failure and clinical recurrence. CONCLUSIONS: Our findings strongly support the importance of PTEN and p27 for the progression of human prostate cancer because loss of PTEN/p27 expression was associated with adverse pathological parameters, tumor cell proliferation, and increased risk of recurrence.

Prostate cancer antigen-3 (PCA3) and PCA3-based nomograms in the diagnosis of prostate cancer: an external validation of Hansen's nomogram on a Norwegian cohort.

OBJECTIVE: The aim of this study was to test the ability of prostate cancer antigen-3 (PCA3) and Hansen's PCA3-based nomogram to predict prostate cancer (PCa) probability in a Norwegian cohort, with the goal of reducing unnecessary biopsies. MATERIAL AND METHODS: Altogether, 127 consecutive patients were recruited to this study at Haukeland University Hospital, Norway. Prostate-specific antigen (PSA), PCA3 score, digital rectal examination (DRE), prostate volume (Pvol) and age were determined. All patients had an extended 10-core biopsy. The performance of PCA3 score and Hansen's nomogram was tested. RESULTS: There were 124 evaluable patients. Among these, 59 patients had PCa on the initial biopsies. Mean PSA, PCA3 score and age were significantly higher and Pvol was significantly lower in patients with PCa. PCA3 scores of 35 and 21 led to a sensitivity of 71% and 81% and specificity of 72% and 55%, respectively. Hansen's nomogram gave an area under the curve (AUC) of 0.806. The intraclass correlation was 0.959 (Cronbach's alpha). Applied to this material, PCa would be missed in 15.2% of patients when applying the suggested threshold probability of 30%, among whom 66.7% had high-grade PCa. With a threshold probability of 20% only one patient had PCa and this was low grade. CONCLUSIONS: Hansen's PCA3-based nomogram is valid for this cohort. A threshold probability of 20% seems more adequate than 30% for this less screened cohort. PCA3 score only affects the biopsy indication in some patients and is recommended only for this subset. The results need to be confirmed in a larger study.