Optimized microvessel density analysis improves prediction of cancer stage from prostate needle biopsies

Dietary tomato inhibits angiogenesis in TRAMP prostate cancer but is not protective with a Western-style diet in this pilot study

Prostate cancer (PCa) remains the second most diagnosed cancer worldwide. Higher body weight is associated with chronic inflammation, increased angiogenesis, and treatment-resistant tumor phenotypes. Dietary tomato reduces PCa risk, which may be due to tomato inhibition of angiogenesis and disruption of androgen signaling. This pilot study investigated the interplay between tomato powder (TP), incorporated into control (CON) and obesogenic (OB) diets, and PCa tumor growth and blood perfusion over time in a transgenic model of PCa (TRAMP). Ultrasound microvessel imaging (UMI) results showed good agreement with gold-standard immunohistochemistry quantification of endothelial cell density, indicating that this technique can be applied to non-invasively monitor tumor blood perfusion in vivo. Greater body weight was positively associated with tumor growth. We also found that TP significantly inhibited prostate tumor angiogenesis but that this inhibition differentially affected measured outcomes depending on CON or OB diets. TP led to reduced tumor growth, intratumoral inflammation, and intratumoral androgen-regulated gene expression (srd5a1, srd5a2) when incorporated with the CON diet but greater tumor growth and intratumoral gene expression when incorporated with the OB diet. Results from this study show that protective benefits from dietary tomato are lost, or may become deleterious, when combined with a Western-style diet.

The role of androgen receptors in vascular and cell proliferation of the prostate adenocarcinomas

Prostate adenocarcinoma (PA) is by incidence and prognosis a unique model for investigating the biomolecular mechanisms involved in tumor progression. In this study, we analyzed the immunoexpression of androgen receptor (AR), cluster of differentiation 105 (CD105) and Ki67 for 61 cases of PA, in relation to the main clinicopathological parameters of the lesions. The AR scores, CD105 microvessel density (MVD) and Ki67 proliferation index (PI) were significantly higher in patients with serum prostate-specific antigen (PSA) above 20 ng/mL, in ductal, colloid and sarcomatoid types of PA, in growth patterns 4–5 or mixed, respectively in the case of high-grade advanced stage tumors, with perineural and vascular invasion, as well as in groups with a reserved prognosis. The results obtained, reflected in the positive linear correlation of AR, CD105 and Ki67 expression, indicate synchronous endocrine, angiogenic and proliferative mechanisms involved in tumor progression, which can be used to optimize the targeted tumor therapy.

Diagnostic, prognostic and predictive parameters in prostate cancer

Prostate cancer (CP) is the most common malignancy in men in America, while it is the second most common in Europe. It is responsible for about 10% of cancer deaths in the same population. It is clinically manifested in various forms, from slow-growing to aggressive forms with pronounced metastatic potential. Diagnosis is made by a well-defined algorithm, which begins with the determination of serum prostate specific antigen values and ends with prostate biopsy as the "gold standard". Pathohistological diagnostic criterias are based on architectural, cytoplasmic, nuclear and characteristics of intraluminal structures, as well as periacinar cleftings, which are deffined as helpfull diagnostic criteria of undoubted importance. Prognostic and predictive parameters are classified into three categories. Some of them are an integral part of routine pathohistologicat report, while others are considered as the diagnostic process progresses. Modern knowledge introduces biomarkers into the everyday practice of personalized medicine, especially when is necessary to treat prostate cancer patients.

Reconsideration of the clinical and histopathological significance of angiogenesis in prostate cancer: Usefulness and limitations of microvessel density measurement

Angiogenesis plays important roles in tumor growth and cancer cell dissemination in almost all cancers. In prostate cancer, there is general agreement that increased angiogenesis is an important factor in determining tumor development and prognosis in these patients. Microvessel density is recognized as a useful marker for evaluating the angiogenic status of cancer tissues. Many investigators have reported that microvessel density is significantly associated with pathological features and outcomes in prostate cancer patients; however, some researchers have expressed opposing opinions. As the reason for such discrepancy, previous reports have suggested differences in the methodologies of measuring microvessel density in cancer tissues. In the present review, we focus on the variation in such methods, including the selected area and the method used for (semi)quantification. In particular, we discuss the relationship between malignancy potential, tumor progression, and survival and differences in the antibodies used for detection of endothelial cells in detail. We briefly compare the pathological significance and prognostic roles of microvessel density measured using von Willebrand factor, CD31, CD34, and CD105. Based on these analyses, the advantages and limitations of microvessel density measurements in prostate cancer tissues are clarified. Improved "real" and "specific" markers of cancer-related angiogenesis are necessary for better predictions of prognoses and for discussion of treatment strategies for patients with prostate cancer. However, establishment of a satisfactory cancer-related endothelial marker could take a long time. Therefore, knowledge regarding the pathological significance of microvessel density - based on understanding of the advantages and limitations of microvessel density determination methods - is important.

Identifying in vivo DCE MRI markers associated with microvessel architecture and gleason grades of prostate cancer

BACKGROUND

To identify computer extracted in vivo dynamic contrast enhanced (DCE) MRI markers associated with quantitative histomorphometric (QH) characteristics of microvessels and Gleason scores (GS) in prostate cancer.

METHODS

This study considered retrospective data from 23 biopsy confirmed prostate cancer patients who underwent 3 Tesla multiparametric MRI before radical prostatectomy (RP). Representative slices from RP specimens were stained with vascular marker CD31. Tumor extent was mapped from RP sections onto DCE MRI using nonlinear registration methods. Seventy-seven microvessel QH features and 18 DCE MRI kinetic features were extracted and evaluated for their ability to distinguish low from intermediate and high GS. The effect of temporal sampling on kinetic features was assessed and correlations between those robust to temporal resolution and microvessel features discriminative of GS were examined.

RESULTS

A total of 12 microvessel architectural features were discriminative of low and intermediate/high grade tumors with area under the receiver operating characteristic curve (AUC) > 0.7. These features were most highly correlated with mean washout gradient (WG) (max rho = -0.62). Independent analysis revealed WG to be moderately robust to temporal resolution (intraclass correlation coefficient [ICC] = 0.63) and WG variance, which was poorly correlated with microvessel features, to be predictive of low grade tumors (AUC = 0.77). Enhancement ratio was the most robust (ICC = 0.96) and discriminative (AUC = 0.78) kinetic feature but was moderately correlated with microvessel features (max rho = -0.52).

CONCLUSION

Computer extracted features of prostate DCE MRI appear to be correlated with microvessel architecture and may be discriminative of low versus intermediate and high GS.

Two-dimensional neovascular complexity is significantly higher in nontumor prostate tissue than in low-risk prostate cancer

Purpose

Prostate cancer is the most frequent cancer in men in Europe. A major focus in urology is the identification of new biomarkers with improved accuracy in patients with low-risk prostate cancer. Here, we evaluated two-dimensional neovascular complexity in prostate tumor and nontumor biopsy cores by use of a computer-aided image analysis system and assessed the correlations between the results and selected clinical and pathological parameters of prostate carcinoma.

Materials and Methods

A total of 280 prostate biopsy sections from a homogeneous series of 70 patients with low-risk prostate cancer (Gleason score 3+3, prostate-specific antigen [PSA]<10 ng/mL, and clinical stage T1c) who underwent systematic biopsy sampling and subsequent radical prostatectomy were analyzed. For each biopsy, 2-µm sections were treated with CD34 antibodies and were digitized by using an image analysis system that automatically estimates the surface fractal dimension.

Results

Our results showed that biopsy sections without cancer were significantly more vascularized than were tumors. No correlations were found between the vascular surface fractal dimension and patient's age, PSA and free-to-total PSA ratios, pathological stage, Gleason score, tumor volume, vascular invasion, capsular penetration, surgical margins, and biochemical recurrence.

Conclusions

The value of angiogenesis in prostate cancer is still controversial. Our findings suggest that low-risk prostate cancer tissues are less vascularized than are nontumor tissues. Further studies are necessary to understand whether angiogenesis is a hallmark of intermediate- and high-risk prostate cancer.

Correlation between CT perfusion and clinico-pathological features in prostate cancer: a prospective study

Background

The aim of the study was to assess the correlation between computed tomography perfusion (PCT) parameters and PSA levels, Gleason score, and pTNM stage in patients with prostate cancer (PCa).

Material/Methods

One hundred twenty-five patients with localized PCa were prospectively enrolled in the study. All patients were diagnosed due to suspicious prostate findings and elevated PSA serum levels and underwent PCT followed by core biopsy and radical prostatectomy. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface (PS) area product were computed in the suspected PCa area and normal prostatic tissue. Core biopsy followed by prostatectomy was performed 2–4 weeks after PCT. Correlation between PCT findings and PSA levels, Gleason score, and pTNM stage were analyzed.

Results

The mean age of patients was 64 years. All patients had elevated PSA levels (mean value 6.2 ng/ml). Nineteen patients (15.9%) were at low risk of recurrence, 91 (76.5%) were at moderate risk, and 9 (7.6%) were at high risk according to National Comprehensive Cancer Network criteria. PCa was visible on PCT as focal peripheral CT enhancement in 119 out of 125 patients (sensitivity 95.2%). Significant correlations between BV, BF, and PS values and PSA level were found (p<0.05), as well as a trend for difference between BV, BF, and PS in poorly and moderately differentiated tumors (according to Gleason score) in comparison with highly differentiated PCa (p<0.08). The analysis also revealed a correlation between mean perfusion values and BV, MTT, PS, and pTNM cancer stage (p<0.04).

Conclusions

Our study suggests that in low- and intermediate- risk patients, PCT parameters correlate with PSA values, Gleason score, and pTNM stage and can be useful for initial tumor staging.

MTA family of proteins in prostate cancer: biology, significance, and therapeutic opportunities

This review summarizes our current understanding of the role of MTA family members, particularly MTA1, with a special emphasis on prostate cancer. The interest for the role of MTA1 in prostate cancer was boosted from our initial findings of MTA1 as a component of "vicious cycle" and a member of bone metastatic signature. Analysis of human prostate tissues, xenograft and transgenic mouse models of prostate cancer, and prostate cancer cell lines has provided support for the role of MTA1 in advanced disease and its potential role in initial stages of prostate tumor progression. Recent discoveries have highlighted a critical role for MTA1 in inflammation-triggered prostate tumorigenesis, epithelial-to-mesenchymal transition, prostate cancer survival pathways, and site metastasis. Evidence for MTA1 as an upstream negative regulator of tumor suppressor genes such as p53 and PTEN has also emerged. MTA1 is involved in prostate tumor angiogenesis by regulating several pro-angiogenic factors. Evidence for MTA1 as a prognostic marker for aggressive prostate cancer and disease recurrence has been described. Importantly, pharmacological dietary agents, namely resveratrol and its analogs, are potentially applicable to prostate cancer prevention, treatment, and control of cancer progression due to their potent inhibitory effects on MTA proteins.

The role of the RhoA/Rho kinase pathway in angiogenesis and its potential value in prostate cancer (Review)

Prostate cancer (PCa) remains a major cause of mortality among males in western countries, with little change in mortality rates observed over the past 25 years. Despite recent advances in therapy, treatment options for metastatic castration-resistant disease remain limited. In terms of chemotherapy, only the combination of docetaxel and prednisone has been shown to improve survival in these patients, but duration of response to therapy is short. There is a continuing unmet need for new systemic interventions that act either alone or synergistically with chemotherapy in patients with progressive PCa. Angiogenesis plays a critical role in tumor growth and metastasis in PCa. Several strategies have been used to target angiogenesis; however, it is becoming increasingly apparent that current anti-angiogenic therapies frequently achieve only modest effects in clinical settings. The RhoA/Rho kinase (ROCK) pathway plays a crucial role in the process of angiogenesis in PCa, and studies have demonstrated that ROCK inhibitors decrease VEGF-induced angiogenesis and tumor cell growth. However, further research is required to fully elucidate the molecular mechanisms involved in this pathway, and the potential value of modulating these mechanisms in the treatment of PCa. This study reviews the current understanding of the role of the RhoA/ROCK pathway in the process of angiogenesis in PCa, and the potential of this pathway as a therapeutic target in the future.

Neoangiogenesis in prostate cancer

Prostate cancer has the second highest incidence among malignant tumors in men in Poland, and the first in the USA. Currently, medical reports state that incidentally non-diagnosed prostate cancer is present in about 30–46% of men over the age of fifty.

Tumor angiogenesis has significant implications in the diagnosis and treatment of various solid tumors. With fast, multi-slice CT scanners and their ability of qualitative and quantitative analysis of tumor angiogenesis, CT perfusion has been the subject of extensive investigation in the past twenty years.

Tumor angiogenesis is characterized morphologically by an increase in the number of blood vessels including new capillaries, capillary sprouts, non-endothelialized capillaries and arterio-venous shunts.

It is stated in the literature that pathological vessel density within prostate cancer is one of the factors determining the extent of the tumor – whether the tumor is confined to the prostate gland or extends beyond the prostate capsule. It was proved that the density of pathological vessels is higher in patients with tumors beyond the prostate capsule.

Initial publications show validity of functional imaging, such as perfusion CT in prostate cancer staging before a surgical procedure. This examination can also show excessive density of pathological vessels within the prostate gland according to increased blood volume (BV) and blood flow (BF) and pathologically increased permeability of the vessels (PS). Vessel abnormalities in the examined area are also indicated by shorter mean transit time (MTT).

Microvessel density is not increased in prostate cancer: digital imaging of routine sections and tissue microarrays

Angiogenesis is considered a prognostic factor and therapy target in many tumors but remains controversial in prostate cancer. This study compares the microvessel density of normal prostate and prostate cancer of different grades using an automated approach to determine its clinical utility. Neoplastic and normal prostatic tissues from 60 prostatectomies were examined by routine histological sections (group I); 136 prostatectomies were used to create tissue microarrays (group II). Microvessel density was calculated using CD31 immunostaining. Automated Cellular Image System (ChromaVision, San Juan Capistrano, CA) and Aperio automated systems were used to digitally analyze microvessel density in Groups I and II respectively. Microvessel density was not significantly increased in tumor versus normal prostate in Group I (P = .303). Both the mean vessel count and vessel area were significantly higher in normal tissue than in tumor either by Automated Cellular Image System or Aperio analysis (P < .05). Aperio analysis in group II additionally showed significantly higher values in normal tissue for vessel lumen (P < .001), whereas vessel perimeter, wall thickness, vessel compactness, and shape were not significantly different (P > .05). Aperio comparison of low- versus high-grade prostate cancer demonstrated that only mean vessel count was increased in high-grade tumors (P = .047); no other automated parameter in either group showed significant association with Gleason scores. Irrespective of methodology, microvessel density was not increased in prostate cancer compared to normal prostate. The bias of using vascular hot spots that possibly contributed to previous contradictory results has been mitigated by automated microvessel density quantitation here. Similar microvessel density of low- and high-grade tumors indicate that microvessel density is neither an important nor reliable prognostic marker for prostate cancer.

Emerging critical role of molecular testing in diagnostic genitourinary pathology

CONTEXT

The unprecedented advances in cancer genetics and genomics are rapidly affecting clinical management and diagnostics in solid tumor oncology. Molecular diagnostics is now an integral part of routine clinical management in patients with lung, colon, and breast cancer. In sharp contrast, molecular biomarkers have been largely excluded from current management algorithms of urologic malignancies.

OBJECTIVE

To discuss promising candidate biomarkers that may soon make their transition to the realm of clinical management of genitourologic malignancies. The need for new treatment alternatives that can improve upon the modest outcome so far in patients with several types of urologic cancer is evident. Well-validated prognostic molecular biomarkers that can help clinicians identify patients in need of early aggressive management are lacking. Identifying robust predictive biomarkers that will stratify response to emerging targeted therapeutics is another crucially needed development. A compiled review of salient studies addressing the topic could be helpful in focusing future efforts.

DATA SOURCES

A PubMed (US National Library of Medicine) search for published studies with the following search terms was conducted: molecular , prognostic , targeted therapy , genomics , theranostics and urinary bladder cancer , prostate adenocarcinoma , and renal cell carcinoma . Articles with large cohorts and multivariate analyses were given preference.

CONCLUSIONS

Our recent understanding of the complex molecular alterations involved in the development and progression of urologic malignancies is yielding novel diagnostic and prognostic molecular tools and opening the doors for experimental targeted therapies for these prevalent, frequently lethal solid tumors.

Evaluation of diffusion-weighted magnetic resonance imaging and contrast-enhanced harmonic ultrasonography in detection and location of prostate transition-zone cancer

This retrospective study was designed to evaluate the value of contrast-enhanced harmonic ultrasonography (CEHU), diffusion-weighted magnetic resonance imaging (DW-MRI) and CEHU plus DW-MRI for the diagnosis of prostate transition-zone (TZ) cancer. In total, 31 TZ cancers in 28 patients and 25 peripheral zone (PZ) cancers in 21 patients without a TZ cancer were evaluated. All patients underwent DW-MRI and CEHU followed by radical prostatectomy. Predictors for the diagnosis of prostate cancer were evaluated in three protocols (CEHU, DW-MRI, CEHU plus DW-MRI). Statistical analysis of the differences between these protocols and receiver operating characteristic (ROC) curve analysis were carried out. CEHU plus DW-MRI had a significantly higher sensitivity, accuracy and negative-predictive value (90.3%, 73.2% and 81.3%, respectively) for TZ cancer than either method alone. The area under the ROC curve values were 0.659, 0.679 and 0.712 for CEHU, DW-MRI, and CEHU plus DW-MRI, respectively. In conclusion, CEHU plus DW-MRI might be a useful protocol for the detection and location of TZ cancer.

Molecular diagnostics in urologic malignancies: a work in progress

CONTEXT

Molecular diagnostic applications are now an integral part of the management algorithms of several solid tumors, such as breast, colon, and lung. In stark contrast, the current clinical management of urologic malignancies is lagging behind. Clinically robust molecular tests that can identify patients who are more likely to respond to a given targeted agent or even those in need of a more aggressive treatment based on well-validated molecular prognosticators are still lacking. Several promising biomarkers for detection, prognosis, and targeted therapeutics are being evaluated.

OBJECTIVE

To discuss candidate biomarkers that may soon make the transition to clinical assay for patients in urologic oncology.

DATA SOURCES

Selected original articles published in the PubMed service of the US National Library of Medicine.

CONCLUSIONS

Recent understanding of the complex molecular alterations involved in the development and progression of urologic malignancies is yielding novel diagnostic and prognostic molecular tools and opening the doors for experimental targeted therapies in these prevalent, frequently lethal solid tumors.

Contrast-enhanced ultrasonography for the detection and characterization of prostate cancer: correlation with microvessel density and Gleason score

AIM

To determine whether there is a correlation between the peak intensity of the lesion at contrast-enhanced ultrasonography and the microvessel density (MVD) and Gleason score in biopsy specimens of prostate cancer.

MATERIALS AND METHODS

Contrast-enhanced ultrasonography using cadence-contrast pulse sequence (CPS) technology was performed in 147 patients with suspected prostate cancer before biopsy. An auto-tracking contrast quantification (ACQ) software was used to analyse the peak intensity (PI) of the lesion. The Gleason score and MVD immunoreactivity were determined in the prostate biopsy specimens. Ultrasound findings were correlated with biopsy findings.

RESULTS

Prostate cancer was detected in 73 of 147 patients. The PI values of prostate cancer patients were significantly higher than those of non-malignant patients [9.81 (4.23) versus 5.69 (3.19) dB; p<0.01]. The mean (SD) PIs of prostate cancer lesions with a Gleason score of 6-9 were 7.08 (3.80), 8.65 (4.08), 9.76 (3.75), and 9.85 (4.13) dB, respectively. The PI value increased significantly with a higher Gleason score (p<0.01). The mean (SD) MVDs observed in prostate cancer lesions with a Gleason score of 6-9 were 52.50 (10.54), 56.85 (10.31), 59.91 (9.29), and 66.04 (11.82), respectively. There was a positive correlation between PI and MVD in prostate cancer, with a correlation coefficient of 0.617. No correlation was found between PI value and age, prostate specific antigen (PSA) or prostate specific antigen density (PSAD) level (p>0.05).

CONCLUSION

The PI obtained by CPS harmonic ultrasonography appears to be of value as an indicator of MVD and increases with a higher Gleason score. CPS harmonic ultrasonography could be promising as a useful imaging technique in the detection and characterization of prostate cancer.

Theranostic and prognostic biomarkers: genomic applications in urological malignancies

Compared to other solid tumours such as breast, colon, and lung, the current clinical management of urological malignancies is lagging behind in terms of utilisation of clinically robust molecular tests that can identify patients that are more likely to respond to a given targeted agent, or even those in need of a more aggressive treatment approach based on well-validated molecular prognosticators. Several promising biomarkers for detection, prognosis, and targeted therapeutics are now under evaluation. The following review discusses some of the candidate biomarkers that may soon make their transition into clinically applicable assays in urological oncology patients.

Angiogenesis as a strategic target for prostate cancer therapy

It is becoming increasingly clear that angiogenesis plays a crucial role in prostate cancer (CaP) survival, progression, and metastasis. Tumor angiogenesis is a hallmark of advanced cancers and an attractive treatment target in multiple solid tumors. By understanding the molecular basis of resistance to androgen withdrawal and chemotherapy in CaP, the rational design of targeted therapeutics is possible. This review summarizes the recent advancements that have improved our understanding of the role of angiogenesis in CaP metastasis and the potential therapeutic efficacy of inhibiting angiogenesis in this disease. Current therapeutic options for patients with metastatic hormone-refractory CaP are very limited. Targeting vasculature is a developing area, which shows promise for the control of late stage and recurrent CaP disease and for overcoming drug resistance. We discuss angiogenesis and its postulated mechanisms and focus on the regulation of angiogenesis in CaP progression and the therapeutic beneficial effects associated with targeting of the CaP vasculature to overcome the resistance to current treatments and CaP recurrence.

Comparison between population average and experimentally measured arterial input function in predicting biopsy results in prostate cancer

RATIONALE AND OBJECTIVES

To test whether individually measured arterial input function (AIF) provides more accurate prostate cancer diagnosis then population average AIF when dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) data are acquired with limited temporal resolution.

MATERIALS AND METHODS

Twenty-six patients with a high clinical suspicion for prostate cancer and no prior treatment underwent DCE MRI examination at 3.0 T before biopsy. DCE MRI data were fitted to a pharmacokinetic model using three forms of AIF: an individually measured, a local population average, and a literature double exponential population average. Receiver operating characteristic (ROC) analysis was used to correlate MRI with the biopsy results. Goodness of fit (chi(2)) for the three AIFs was compared using nonparametric Mann-Whitney test.

RESULTS

Average volume transfer constant (K(trans)) values were significantly higher in tumor than in normal peripheral zone for all three AIFs. The individually measured and the local population average AIFs had the highest sensitivity (76%), whereas the double exponential AIF had the highest specificity (82%). The areas under the ROC curves were not significantly different between any of the AIFs (0.81, 0.76, and 0.81 for the individually measured, local population average, and double exponential AIFs, respectively). chi(2) was not significantly different for the three AIFs; however, it was significantly higher in enhancing than in nonenhancing regions for all three AIFs.

CONCLUSIONS

These results suggest that, when DCE MRI data are acquired with limited temporal resolution, experimentally measured individual AIF is not significantly better than population average AIF in predicting the biopsy results in prostate cancer.

Angiogenesis inhibition in prostate cancer: current uses and future promises

Angiogenesis has been well recognized as a fundamental part of a multistep process in the evolution of cancer progression, invasion, and metastasis. Strategies for inhibiting angiogenesis have been one of the most robust fields of cancer investigation, focusing on the vascular endothelial growth factor (VEGF) family and its receptors. There are numerous regulatory drug approvals to date for the use of these agents in treating a variety of solid tumors. While therapeutic efficacy has been established, challenges remain with regards to overcoming resistance and assessing response to antiangiogenic therapies. Prostate cancer is the most common noncutaneous malignancy among American men and angiogenesis plays a role in disease progression. The use of antiangiogenesis agents in prostate cancer has been promising and is hereby explored.

Contrast-enhanced harmonic ultrasonography for the assessment of prostate cancer aggressiveness: a preliminary study

OBJECTIVE

To determine whether contrast-enhanced harmonic ultrasonography can be used to predict the aggressiveness of prostate cancer.

MATERIALS AND METHODS

Contrast-enhanced harmonic ultrasonography was performed in 103 patients suspected of prostate cancer before biopsy. Time intensity curves were reconstructed for systematic biopsy sites and sonographic abnormalities. The characteristics of the curves were described using hemodynamic indices including arrival time (AT), time-to-peak (TTP), and peak intensity (PI). The differences of hemodynamic indices between high-grade and low-grade cancer were analyzed and the correlations between the hemodynamic indices and biopsy Gleason score were studied.

RESULTS

Prostate cancer was detected in 41 of 103 patients and there were significant differences in the hemodynamic indices between the biopsy sites of the non-malignant patients and prostate cancer lesions (p < 0.05). The prostate biopsies revealed 154 prostate cancer lesions, including 31 low-grade lesions and 123 high-grade lesions. The hemodynamic indices AT and TTP of high-grade tumors were significantly shorter than those of low-grade tumors (p = 0.001, 0.002). In addition, high-grade peripheral zone (PZ) tumors had higher PI than low-grade PZ tumors (p = 0.009). The PZ prostate cancer Gleason score correlated with PI, AT and TTP, with Spearman correlation coefficients of 0.223, -0.335, and -0.351, respectively (p = 0.013, < 0.001 and < 0.001).

CONCLUSION

Contrast-enhanced ultrasound measurements of hemodynamic indices correlate with the prostate cancer Gleason score.

Is tumor vascularity in prostate core biopsies a predictor of PSA recurrence after radical prostatectomy?

The purposes of this study were to evaluate if tumour vascularity by Chalkley counting (TVC) in prostate core biopsies can be a predictor of PSA recurrence after radical prostatectomy in prostate cancer and to estimate the concordance between the TVC in core biopsies and the subsequently examined prostatectomy specimen. All patients, with Gleason score < or =7 in core biopsy, clinical stage T1 or T2 who had a radical prostatectomy during 1990-1997 at Sahlgrenska University Hospital, were selected as a primary group. Patients with neoadjuvant hormonal therapy were excluded. The patients were divided into two groups, one with PSA recurrence and one group without PSA recurrence. 25 patients had PSA recurrence during the follow up period and 25 patients from non-recurrence group were randomly selected. TVC was assessed from the prostate tissue by immunostaining against CD34. TVC was statistically significant predictor of PSA relapse. The PSA-free survival rate was only 17% in patients within the highest TVC quartile compared to 67% in patients within the lowest TVC quartile.

Dynamic contrast-enhanced magnetic resonance imaging in prostate cancer

Prostate cancer remains a major health concern for the male population. During the past decade, a dramatic increase in prostate-specific antigen and transurethral resection of the prostate has resulted in increased detection rate of small lesions and increased incidence of this disease. Needle biopsies in asymptomatic men have also contributed to the increased incidence of prostate cancer, leading to an increasing incidence-to-mortality ratio. Magnetic resonance imaging (MRI) is the modality of choice in prostate cancer patients with increased prostate-specific antigen levels before or after prostate cancer diagnosis confirmed by biopsy and T2-weighted imaging (T2W) has been used as a standard technique in detection. During the last decade, dynamic contrast-enhanced MRI has emerged as one of the main techniques used in multiparametric MRI of the prostate gland in cancer patients. Dynamic contrast-enhanced MRI has been routinely used for detection and diagnosis of the tumor, for staging and monitoring the therapeutic response, as well as for guiding targeted biopsies in patients with suspected prostate cancer or with a negative biopsy result. In this article, we are going to review the analysis techniques of dynamic contrast-enhanced MRI and its various clinical applications in prostate cancer patients.

Simultaneous quantification of perfusion and permeability in the prostate using dynamic contrast-enhanced magnetic resonance imaging with an inversion-prepared dual-contrast sequence

The aim of the present study was to quantify both perfusion and extravasation in the prostate to discriminate tumor from healthy tissue, which might be achieved by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using a nonspecific low-molecular-weight contrast medium (CM). To determine extravasation as well as tissue perfusion an inversion-prepared dual-contrast sequence employing a parallel acquisition technique (PAT) was designed for interleaved acquisition of T(1)-weighted images for extravasation measurement and T(2)*-weighted images for determination of the highly concentrated bolus with a sufficiently high temporal and spatial resolution at an acceptable signal-to-noise ratio. Thirteen patients with proven prostate cancer were examined with the sequence using a combined body-array prostate coil. Before pharmacokinetic evaluation the images were intensity-corrected and, if required, motion-corrected. The pharmacokinetic model used to calculate perfusion, permeability, blood volume, interstitial volume, transit time, and vessel size index included two compartments and a correction of delay and dispersion of the arterial input function. The information provided by the dual-contrast sequence allowed application of a more elaborate model for evaluation and enabled quantification of all parameters. Peripheral prostate tumors were found to differ from peripheral healthy prostate tissue in perfusion (1.38 mL/(min cm(3)) vs. 0.23 mL/(min cm(3)), p=0.004), mean transit time (2.88 vs. 4.88 s, p=0.039), and blood volume (1.9 vs. 0.7%, p=0.019). A inversion-prepared dual-contrast sequence acquiring T(1)- and T*(2)-weighted images with sufficient temporal resolution and signal-to-noise ratio was successfully applied in patients with prostate cancer to quantify all pharmacokinetic parameters of inflow and extravasation of a low-molecular-weight inert tracer.

[The natural history of metastatic prostate cancer]

Prostate cancer is a pathology which progress with successive stages directly dependant on hormonosensitivity. When metastasis occur, cell modifications and biologic transformations lead to disease diffusion. PSA is useful to practically follow the evolution of the prostate cancer but it is probably the molecular biology which probably will be necessary to get prognostic and predictive markers of metastasis power. At each step of the metastatic cascade, it is possible to imagine a specific targeted therapy for this disease which is today non curable.

Advances in transrectal ultrasound imaging of the prostate

Grayscale imaging of the prostate is the basic method for diagnostic evaluation and biopsy guidance. Doppler imaging may improve sensitivity for detection of prostate cancer. Microbubble contrast agents represent a major advance to more selectively demonstrate neovascular flow within the prostate. Recently, real-time elastography has been introduced to improve detection of cancer based upon changes in tissue stiffness. As diagnostic methods improve, the ultimate hope is to eliminate biopsy in patients without cancer. New ultrasound-based treatment systems, such as high-intensity focused ultrasound ablative therapy for prostate cancer, may someday allow diagnosis and treatment of prostate cancer to be completed in one sitting.

Contrast enhanced ultrasound flash replenishment method for directed prostate biopsies

PURPOSE

We evaluated prostate cancer detection with contrast enhanced ultrasound of the prostate using MicroFlow Imaging (Toshiba America Medical Systems, Tustin, California) compared to systematic biopsy.

MATERIALS AND METHODS

A total of 60 patients referred for prostate biopsy were evaluated with pre-contrast and contrast enhanced MicroFlow Imaging transrectal ultrasound. MicroFlow Imaging is a flash replenishment technique that uses high power flash pulses to destroy contrast microbubbles, followed by low power pulses to demonstrate contrast replenishment. A composite image depicting the vascular architecture is constructed through maximum intensity capture of temporal data in consecutive low power images. Using MicroFlow Imaging up to 5 directed biopsy cores were obtained from areas of abnormal vascular enhancement or morphology, followed by a systematic 10-core biopsy protocol.

RESULTS

A biopsy positive for cancer was found in 79 of the 825 cores (10%) from 18 of the 60 subjects (30%). Positive biopsies were obtained in 50 of 600 systematic core biopsies (8.3%) and in 29 of 225 directed cores (13%) (OR 2.02, p = 0.034). Five of the 18 patients diagnosed with cancer were identified only by systematic biopsy, 2 were identified only by directed biopsy with MicroFlow Imaging and 11 were identified by the 2 techniques (p >0.25). Twice the number of patients was detected per core with directed vs systematic biopsy (0.058 vs 0.027).

CONCLUSIONS

The vascular detail provided by MicroFlow Imaging allowed directed biopsy of these areas with increased detection of prostate cancer. Although a minority of cancers were not detected with MicroFlow Imaging directed biopsy, this technique detected twice as many patients with prostate cancer per biopsy core.

The metastatic cascade in prostate cancer

Morbidity and mortality due to prostate cancer are mainly a result of prostate cancer metastases. After the initial neoplastic transformation of cells, the process of metastasis involves a series of sequential steps, which involve neoangiogenesis and lymphangiogenesis, loss of adhesion with migration away from the primary tumour and entry into the systemic vasculature or lymphatics. Metastatic growth in sites such as lymph nodes and bone marrow then involves the specific non-random homing of prostate cancer cells. An appreciation and understanding of this metastatic cascade in relation to prostate cancer is clinically important in order to stratify men with prostate cancer into prognostic groups. Moreover, it is crucial in the future development of therapies that can prevent metastases.

Role of angiogenesis in chronic lymphocytic leukemia

Angiogenesis is a physiologic process of new blood vessels formation mediated by various cytokines called angiogenic and angiostatic factors. Although its potential pathophysiologic role in solid tumors has been extensively studied for more than 3 decades, enhancement of angiogenesis in chronic lymphocytic leukemia (CLL) and other malignant hematological disorders has been recognized more recently. An increased level of angiogenesis has been documented by various experimental methods both in bone marrow and lymph nodes of patients with CLL. Although the role of angiogenesis in the pathophysiology of this disease remains to be fully elucidated, experimental data suggest that several angiogenic factors play a role in the disease progression. Biologic markers of angiogenesis were also shown to be of prognostic relevance in CLL. The current findings provide the rationale for investigating antiangiogenic agents in CLL. In the current review angiogenesis in CLL is discussed and its potential diagnostic and therapeutic applications.

Histopathology reporting of prostate needle biopsies. 2005 update

This report reviews the diagnostic and prognostic importance of the pathologic findings in prostate needle biopsies. The morphological findings of the needle biopsy may be placed into one of the following five categories: prostate cancer, atypical small acinar proliferation, high-grade prostatic intraepithelial neoplasia, inflammation, and benign prostatic tissue. While the prime goal of the biopsy is to diagnose prostatic adenocarcinoma, once carcinoma is detected, further descriptive information regarding the type, amount of cancer, and grade forms the cornerstone for contemporary management of the patient and for assessment of the potential for local cure and the risk for distant metastasis. The information provided in the needle biopsy report regarding the attributes of carcinoma is used depending on the individual patient's medical condition and preference and on the treating physician's evaluation to determine whether any form of treatment is indicated and, if so, the type of therapy.

Imaging for Prostate Cancer

The increased incidence and awareness of prostate cancer, together with developments in treatment, has generated a significant need for appropriate imaging to detect and stage the tumour initially, guide radiotherapy delivery and monitor disease on follow-up. Transrectal ultrasound is usually the first imaging investigation, and its role is primarily to guide prostate needle biopsy. It also has an established role in imaging-guided treatments, such as brachytherapy. Magnetic resonance imaging has developed considerably in recent years, and is now the principal staging investigation before treatment. Innovations in functional and biological imaging of the prostate will, in the future, contribute valuable information to support parallel developments in radiotherapy techniques for prostate cancer. The ultimate goal is a coordinated diagnostic and therapeutic approach to individualise and optimise the treatment plan for patients with prostate cancer.

Quantitative Computed Tomography Perfusion of Prostate Cancer: Correlation with Whole-Mount Pathology

PURPOSE

Microvessel density within the prostate is associated with presence of cancer, disease stage, and disease-specific survival. We evaluated multidetector computed tomography (CT) to estimate prostate perfusion and localize prostate cancer.

PATIENTS AND METHODS

Ten subjects were evaluated with contrast enhanced CT before radical prostatectomy with the Mx8000IDT 16-slice scanner. Following baseline pelvic scan, 100 cc of Optiray 300 was administered intravenously (4 cc per second). Repeated dynamic scans through the prostate were obtained at 20, 30, 40, 50, and 60 seconds following initiation of contrast injection. Computed tomography perfusion was compared with pathologic findings of Gleason score and tumor volume on whole-mount prostatectomy specimens.

RESULTS

Conventional adenocarcinoma (Gleason score, 6-10) was present in all subjects, including one who also demonstrated a mucinous variant of prostate cancer. Visible focal CT enhancement was noted in 1 patient with a high-volume tumor and a Gleason score of 10. A positive correlation between local estimates of CT perfusion and percent of prostate volume occupied by tumor in each sextant was found for half of the subjects (Pearson correlation coefficient, 0.3-0.95; mean, 0.48) but statistically significant correlation (P < 0.05; Pearson coefficient, 0.9-0.95) was present in only the 2 subjects with the highest Gleason scores (8 and 10) and the highest tumor volume (> or = 50% in > or = 1 sextant region).

CONCLUSION

Visible enhancement of prostate cancer during dynamic CT is present in a minority of subjects. Correlation between quantitative CT perfusion and tumor location is statistically significant only in subjects with localized high-volume, poorly differentiated prostate cancer.

The relationship between angiogenesis and cyclooxygenase-2 expression in prostate cancer

OBJECTIVE

To test the hypothesis that angiogenesis in prostate cancer is associated with tumour invasion and metastasis, and that this is mediated through increased cyclooxygenase-2 (COX-2) expression.

PATIENTS AND METHODS

Angiogenesis was assessed in 105 patients with either prostate cancer (79) or benign prostatic hyperplasia (BPH, 26) and these data correlated with levels of COX-2 expression in the same dataset. The mean microvessel density (MVD) was analysed as a marker of angiogenesis, using the endothelial antigen CD34 stained by immunohistochemistry.

RESULTS

There was no difference in MVD in progressive tumour stages compared with BPH. There was a negative correlation between MVD and COX-2 expression, but the effect of increased COX-2 expression on MVD was not marked.

CONCLUSION

These data suggest that COX-2 drives tumour spread in prostate cancer by means other than the promotion of angiogenesis.

Comparison of microvessel densities in rat prostate tissues treated with finasteride, bicalutamide and surgical castration: A preliminary study

BACKGROUND

A group of anti-androgens with different mechanisms of action and adverse effects have been investigated in patients with gross hematuria related to benign prostate hyperplasia; however, there is not yet any consensus about the standard management of these patients. The present study aims to identify if any one type of the hormonal intervention is superior in terms of the suppression of microvessel formation in the prostate.

MATERIALS AND METHODS

A total of 28 mature, healthy male Sprague-Dawley rats (300 +/- 50 g) were used in this study. The rats were randomly assigned to one of four groups (n = 7 per group). The effects of three different hormonal therapies on angiogenesis and microvascularity in rat ventral prostate were compared. Groups 1 and 2 were treated for 28 days with finasteride and bicalutamide, respectively, and rats from Group 3 underwent surgical castration. Following treatment, all rats included in the study underwent dissection of the ventral prostate and immunohistochemical analysis of microvessel density by factor VIII-related antigen.

RESULTS

The mean number of microvessels in the finasteride and bicalutamide groups was 24.5 (+/-8.44 SE) and 27 (+/-9.89 SE) respectively. In contrast, the castration and control groups had microvessel numbers of 12.9 (+/-5.35 SE) and 40.3 (+/-5.03 SE) respectively. Differences were statistically significant between all three treatment groups and the controls (P < 0.005); the number of microvessels in rat prostate tissues of the control group was significantly higher than the treatment groups. Mean microvessel densities in the bicalutamide and finasteride groups were significantly higher than microvessel densities in the castration group (P < 0.005). There was no statistically significant difference between mean microvessel number in rat prostate tissue treated with finasteride or bicalutamide (P > 0.05).

CONCLUSIONS

Even though finasteride was not as effective as castration in reducing microvessel number, its effect was equal to that of bicalutamide in terms of suppressing the angiogenesis in prostatic tissue. Based on the findings of the present study, finasteride might offer a viable option in the management of macroscopic hematuria by inhibition of microvessel formation within the prostatic tissue. Further clinical studies are warranted.

Detection of prostate carcinoma with contrast-enhanced sonography using intermittent harmonic imaging

BACKGROUND

The purpose of this study was to assess prostate carcinoma detection and discrimination of benign from malignant prostate tissue with contrast-enhanced ultrasonography.

METHODS

In all, 301 subjects referred for prostate biopsy were evaluated with contrast-enhanced sonography using continuous harmonic imaging (CHI) and intermittent harmonic imaging (IHI) with interscan delay times of 0.2, 0.5, 1.0, 2.0 seconds, as well as continuous color and power Doppler. Targeted biopsy cores were obtained from sites of greatest enhancement, followed by spatially distributed cores in a modified sextant distribution.

RESULTS

Carcinoma was detected in 363 biopsy cores from 104 of 301 subjects (35%). Carcinoma was found in 15.5% (175 of 1133) of targeted cores and 10.4% (188 of 1806) of sextant cores (P < 0.01). Among subjects with carcinoma, targeted cores were twice as likely to be positive (odds ratio [OR] = 2.0, P < 0.001). Clustered receiver operating characteristic (ROC) analysis of imaging findings at sextant biopsy sites yielded the following Az values: precontrast gray scale: 0.58; precontrast color Doppler: 0.53; precontrast power Doppler: 0.58; CHI: 0.62; IHI (0.2 sec): 0.64; IHI (0.5 sec): 0.63; IHI (1.0 sec): 0.65; IHI (2.0 sec): 0.61; contrast-enhanced color Doppler: 0.60; contrast-enhanced power Doppler: 0.62. A statistically significant benefit was found for IHI over baseline imaging (P < 0.05).

CONCLUSIONS

The carcinoma detection rate of contrast-enhanced targeted cores is significantly higher when compared with sextant cores. Contrast-enhanced transrectal sonography with IHI provides a statistically significant improvement in discrimination between benign and malignant biopsy sites. However, given the relatively low ROC areas, this technique may not be sufficient to predict which patients have benign versus malignant disease.

Thalidomide and analogues: current proposed mechanisms and therapeutic usage

Microvessel density is a prognostic factor for many cancers, including prostate. For this reason, several studies and therapeutic approaches that target the tumor microvasculature have been attempted. Thalidomide has long been recognized as an antiangiogenic molecule. Recently, this drug has regained favor as an anticancer agent and is in clinical trial for multiple myeloma and prostate cancer, among others. This article will briefly review the proposed mechanisms of action for thalidomide, discuss why these activities are of therapeutic value in diseases currently undergoing clinical trials, and summarize the current status of clinical trials for prostate cancer. The focus will be predominantly on the relationship of thalidomide to angiogenesis, as well as on the future and potential value of thalidomide-inspired structural derivatives.

Angiogenesis and prostate cancer tumor growth

The initiation of new blood vessels through angiogenesis is critical to tumor growth. Tumor cells release soluble angiogenic factors that induce neovascularization, without which nutrients and oxygen would not be available to allow tumors to grow more than 2-3 mm in diameter. This "angiogenic switch" or angiogenic phenotype requires an imbalance between proangiogenic and antiangiogenic factors since the formation of new blood vessels is highly regulated. This review discusses angiogenesis mediators, and the potential for manipulation of angiogenic factors as a practical cancer therapy, particularly in prostate cancer.

Association of preoperative plasma levels of vascular endothelial growth factor and soluble vascular cell adhesion molecule-1 with lymph node status and biochemical progression after radical prostatectomy

PURPOSE

Angiogenesis is a critical process for cancer progression. We tested whether elevated circulating levels of the angiogenesis-related markers vascular endothelial growth factor (VEGF) and/or soluble vascular cell adhesion molecule-1 (sVCAM-1) are associated with prostate cancer diagnosis, stage, progression, and metastasis.

PATIENTS AND METHODS

Plasma levels of VEGF and sVCAM-1 were measured on frozen, archival plasma obtained preoperatively from 215 consecutive patients who underwent radical prostatectomy for clinically localized disease, nine men with untreated prostate cancer metastatic to bones, and 40 healthy men without cancer.

RESULTS

Plasma levels of both VEGF and sVCAM-1 were highest in patients with bone metastases (P <.001). VEGF levels were higher in patients with clinically localized disease than in healthy controls (P <.001). VEGF levels were elevated in patients with biopsy and final Gleason sum > or = 7 (P =.036 and P =.020, respectively) and extraprostatic extension (P =.047). Higher preoperative VEGF was independently associated with metastases to lymph nodes (P <.001). Both VEGF and sVCAM-1 were independently associated with biochemical progression after adjustment for the effects of standard preoperative features (P =.014 and P =.039, respectively). VEGF remained independently associated with biochemical progression after adjustment for standard postoperative features (P =.019).

CONCLUSION

Plasma levels of VEGF increased incrementally from healthy controls to patients with clinically localized disease to patients with lymph node and skeletal metastases. Higher preoperative VEGF was independently associated with metastases to lymph nodes and biochemical progression after surgery in both pre- and postoperative models. Plasma sVCAM-1 was elevated in men with bone metastases and was associated with biochemical progression in a preoperative model.

Short-term human prostate primary xenografts: an in vivo model of human prostate cancer vasculature and angiogenesis

Transgenic spontaneously occurring and transplantable xenograft models of adenocarcinoma of the prostate (CaP) are established tools for the study of CaP progression and metastasis. However, no animal model of CaP has been characterized that recapitulates the response of the human prostate vascular compartment to the evolving tumor microenvironment during CaP progression. We report that primary xenografts of human CaP and of noninvolved areas of the human prostate peripheral zone transplanted to athymic nude mice provide a unique model of human angiogenesis occurring in an intact human prostate tissue microenvironment. Angiogenesis in human kidney primary xenografts established from human renal cell carcinoma and noninvolved kidney tissue, a highly vascular organ and cancer, was compared with angiogenesis in xenografts from the relatively less vascularized prostate. Immunohistochemical identification of the human versus mouse host origin of the endothelial cells and of human endothelial cell proliferation in the human prostate and human kidney xenografts demonstrated that: (a) the majority of the vessels in primary xenografts of benign and malignant tissue of both organs were lined with human endothelial cells through the 30-day study period; (b) the mean vessel density was increased in both the CaP and benign prostate xenografts relative to the initial tissue, whereas there was no significant difference in mean vessel density in the renal cell carcinoma and benign kidney xenografts compared with the initial tissue; and (c) the number of vessels with proliferating endothelial cells in primary xenografts of CaP and benign prostate increased compared with their respective initial tissue specimens, whereas the number of vessels with proliferating endothelial cells decreased in the benign kidney xenografts. Short-term primary human prostate xenografts, therefore, represent a valuable in vivo model for the study of human angiogenesis within a human tissue microenvironment and for comparison of angiogenesis in CaP versus benign prostate.

The reporting of prostate cancer on needle biopsy: prognostic and therapeutic implications and the utility of diagnostic markers

Prostate needle biopsy remains the gold standard for diagnosing prostate cancer. Prostate cancer on needle biopsy can be evaluated by numerous techniques of quantifying tumour extent, Gleason score, and the presence of perineural invasion (PNI). These modalities can help clinicians in assessing the risk of extraprostatic disease, progression likelihood, and in helping men with prostate cancer choose among therapeutic options. This review details the information that should be included in the routine pathology report. Recent advances in molecular biology of prostate carcinogenesis have identified many molecular markers for prostate cancer. While several are extremely promising as diagnostic immunohistochemical markers, other prognostic markers are not yet ready to be used in routine practice until they are validated by large prospective studies.

Effect of allogeneic stem cell transplantation on bone marrow angiogenesis in chronic myelogenous leukemia

Increased bone marrow angiogenesis is a poor prognostic marker in patients with chronic myelogenous leukemia (CML). Allogeneic stem cell transplantation (ASCT) can be curative for patients with CML. Studies in myeloma have shown persistent increased bone marrow microvessel density (MVD) after autologous transplantation. It is not clear if abnormal bone marrow angiogenesis persists following a curative intervention like allogeneic transplantation. We evaluated MVD from bone marrow samples obtained just prior to and at 3-5 months after ASCT in 24 patients with CML. The median MVD pre-transplant was 14 (4-37), with 11 patients having high-grade angiogenesis and 13 having low grade. The median post transplant MVD was 20 (range 5-36), with 12 patients having high-grade angiogenesis and 12 low grade. The median time between biopsies was 4 months (range 1-6 months). The microvessels in the post transplant bone marrow appeared morphologically different with striking dilatation and sinusoidal appearance compared to the pre-transplant marrow. However, there was no significant change in MVD following transplant (P=0.8, paired t-test). Abnormal bone marrow angiogenesis appears to persist in the bone marrow following ASCT for CML, at least in the short term.

Multivariate models to predict clinically important outcomes at prostatectomy for patients with organ-confined disease and needle biopsy Gleason scores of 6 or less

The objective of this study was to determine the clinical and biopsy features associated with outcomes at radical retropubic prostatectomy (RRP) in patients with clinically organ-confined prostate cancers and biopsy Gleason scores (GS) of 6 or less. We reviewed 274 biopsies with GS 6 or less cancers from patients with clinically organ-confined disease between 1995 and 1998 to determine statistically significant predictors for the following outcomes at RRP: tumor volume, small (<0.5 cc), confined (pT2) tumors with RRP GS of 6 or less (potentially "insignificant" tumors), and extraprostatic extension (EPE). Clinical and pathologic features evaluated included age, serum prostate specific antigen (PSA), clinical stage, percent biopsy cores and surface area positive for cancer (tumor extent), perineural invasion, MIB-I proliferation, and DNA ploidy by digital image analysis (DIA). Multivariate analyses showed that biopsy tumor extent (median percent surface area positive 3.3%; P < 0.001 and median biopsy cores positive 28.6%; P = 0.001) and PSA (median 5.5 ng/mL; P = 0.009) predicted tumor volume (median 1.4 cc). Biopsy tumor extent (P = 0.002), PSA (P = 0.002), and percent S-phase nuclei (P = 0.050) predicted potentially "insignificant" tumors at RRP (n = 76, 28%). Percent surface area positive for cancer (P = 0.003) predicted EPE (n = 22, 8%). DNA ploidy (n = 211, 79% diploid) and MIB-I proliferation (median 1.4%) did not add information to predict these RRP outcomes. Biopsy tumor extent and serum PSA were significantly associated with tumor volume. Biopsy tumor extent, serum PSA, and percent S-phase nuclei by DIA were predictive of potentially insignificant tumors. Patients with clinically confined disease, <5% biopsy surface area positive for cancer, <20% biopsy cores positive for cancer, and GS 6 or less, had a 48% chance of having a potentially insignificant tumor at diagnosis if the serum PSA was <10 ng/mL. Percent surface area predicted EPE at RRP. DNA ploidy and MIB-I proliferation by DIA did not provide additional information.

Current status of thalidomide and its role in the treatment of metastatic prostate cancer

Following the discovery of its anti-angiogenic properties and despite its tragic history, thalidomide has re-surfaced in the field of oncology. Concurrent with its evaluation in various clinical trials for cancer, thalidomide's mechanism of action is sought and new analogues with improved efficacy and pharmacological profile are emerging. This review is a critical evaluation of thalidomide metabolism, molecular targets, anti-angiogenic activity and clinical efficacy with an emphasis on metastatic prostate cancer.