Markers and meaning of primary treatment failure

Overexpression of YTHDC2 contributes to the progression of prostate cancer and predicts poor outcomes in patients with prostate cancer

YTH domain-containing protein 2 (YTHDC2), a member of N6-methyladenosine (m6A) readers, has been reported to be closely associated with multiple cancer types. However, very little is known about the YTHDC2 gene and its involvement in prostate cancer. YTHDC2 protein expression level was analyzed and correlated to clinical outcomes in prostate cancer patients who underwent prostatectomy in Guizhou Provincial People's Hospital. The YTHDC2 expression level was also detected in prostate cancer cell lines and an immortalized prostate epithelial cell line BPH-1 and RWPE1 by quantitative real-time reverse transcription polymerase chain reaction. Furthermore, we established stable cell lines (DU145 and PC-3) transfected with either empty vector or the full-length YTHDC2 gene and conducted cell function assays in vitro. Fisher's exact test and Pearson χ² test were employed, Kaplan-Meier method was used for the survival analysis. Of 32 patient samples who enrolled in this study, YTHDC2 was significantly upregulated in prostate cancer (PCa) patients with higher Gleason scores and serum prostate-specific antigen levels. YTHDC2 expression was significantly elevated in all PCa cell lines compared to BPH-1 and RWPE1 (all p < 0.05). Functionally, the enforced expression of YTHDC2 markedly promoted cell growth, migration, and invasion efficacies in prostate cancer cells. Our data indicate that YTHDC2 upregulation may be potentially associated with the prognosis of prostate cancer patients.

Analysis of separate training and validation radical prostatectomy cohorts identifies 0.25 mm diameter as an optimal definition for "large" cribriform prostatic adenocarcinoma

Cribriform growth pattern is well-established as an adverse pathologic feature in prostate cancer. The literature suggests "large" cribriform glands associate with aggressive behavior; however, published studies use varying definitions for "large". We aimed to identify an outcome-based quantitative cut-off for "large" vs "small" cribriform glands. We conducted an initial training phase using the tissue microarray based Canary retrospective radical prostatectomy cohort. Of 1287 patients analyzed, cribriform growth was observed in 307 (24%). Using Kaplan-Meier estimates of recurrence-free survival curves (RFS) that were stratified by cribriform gland size, we identified 0.25 mm as the optimal cutoff to identify more aggressive disease. In univariable and multivariable Cox proportional hazard analyses, size >0.25 mm was a significant predictor of worse RFS compared to patients with cribriform glands ≤0.25 mm, independent of pre-operative PSA, grade, stage and margin status (p < 0.001). In addition, two different subset analyses of low-intermediate risk cases (cases with Gleason score ≤ 3 + 4 = 7; and cases with Gleason score = 3 + 4 = 7/4 + 3 = 7) likewise demonstrated patients with largest cribriform diameter >0.25 mm had a significantly lower RFS relative to patients with cribriform glands ≤0.25 mm (each subset p = 0.004). Furthermore, there was no significant difference in outcomes between patients with cribriform glands ≤ 0.25 mm and patients without cribriform glands. The >0.25 mm cut-off was validated as statistically significant in a separate 419 patient, completely embedded whole-section radical prostatectomy cohort by biochemical recurrence, metastasis-free survival, and disease specific death, even when cases with admixed Gleason pattern 5 carcinoma were excluded. In summary, our findings support reporting cribriform gland size and identify 0.25 mm as an optimal outcome-based quantitative measure for defining "large" cribriform glands. Moreover, cribriform glands >0.25 mm are associated with potential for metastatic disease independent of Gleason pattern 5 adenocarcinoma.

Tumor Suppressor Role and Clinical Significance of the FEV Gene in Prostate Cancer

Background

In our previous research, we developed a 32-gene risk index model that may be utilized as a robust prognostic method for predicting prostate cancer (PCa) recurrence after surgery. Among the 32 genes, the Fifth Ewing Variant (FEV) gene was one of the top downregulated genes in relapsed PCa. However, current understanding of the FEV gene and its involvement in PCa is limited.

Methods

FEV mRNA expression was analyzed and correlated to clinical outcomes in PCa patients who underwent prostatectomy at the Massachusetts General Hospital. Specimens from tissue microarray (TMA) including 102 prostate cancer patients were analysis for the expression of FEV. Meanwhile, FEV expression profiles were also assessed in PCa cell lines and in BPH-1 prostate epithelial cells using western blotting and quantitative reverse transcription-PCR (qRT-PCR). Furthermore, we transfected LNCaP and PC-3 cells with either an empty vector or full-length FEV gene and performed in vitro cell functional assays. The part FEV plays in tumor xenograft growth was also assessed in vivo.

Results

Of the 191 patients included in this study base on the DASL dataset, 77 (40.3%) and 24 (13.6%), respectively, developed prostate-specific antigen (PSA) relapse and metastasis postradical prostatectomy. Significant FEV downregulation was observed in PCa patients showing PSA failure and metastasis. The protein expression of FEV was significantly negatively correlated with the Gleason score and pathological stage in prostate cancer tissues. Similarly, FEV expression significantly decreased in all PCa cell lines relative to BPH-1 (all P < 0.05). Functional assays revealed that FEV expression markedly inhibited PCa cell growth, migration, and invasion, which in turn significantly repressed the growth of tumor xenografts in vivo.

Conclusion

The results of this study suggest an association between downregulated FEV expression and PSA relapse in PCa patients. In addition, FEV may act as a tumor suppressor in PCa.

Biochemical Recurrence in Prostate Cancer and Temporal Association to Bone Metastasis

Case series

Patient: Male, 78 • Male, 65

Final Diagnosis: Bone metastasis from prostate cancer recurrence

Symptoms: Joint pain

Medication: —

Clinical Procedure: —

Specialty: Uro-Oncology

Effect of radical prostatectomy on levels of cancer related epitopes in circulating macrophages of patients with clinically localized prostate cancer

OBJECTIVE

Epitopes of the apoptosis related protein DNaseX (Apo10) and the pentose-phosphate-pathway associated protein transketolase-like 1 (TKTL1) have been shown to be increased in circulating macrophages of patients with different cancer types including prostate cancer (PC). So far, the effect of cancer-specific therapies on the levels of these markers in blood samples of patients with PC has not been evaluated yet. The aim of the present study was to prospectively assess the effect of surgical removal of the prostate on levels of Apo10 and TKTL1 in blood macrophages using Epitope Detection In Monocytes (EDIM).

METHODS

We prospectively enrolled 174 patients with clinically localized PC undergoing radical prostatectomy. Peripheral blood was collected preoperatively in all patients and postoperatively in a subgroup of 72 patients. We separately assessed the proportion of CD14/CD16-positive monocytes expressing Apo10 and TKTL1 using flow cytometry. The proportion of positive cells was multiplied by ten to generate a score for Apo10 and TKTL1, separately. Pre- and postoperative scores of Apo10 and TKTL1 were compared. Moreover, results were correlated with clinicopathologic parameters.

RESULTS

In the total cohort, Median preoperative Apo10 and TKTL1 scores were 136 (Range 101-254) and 139 (102-216). In patients who underwent blood collection and testing either pre- and postoperatively (n = 72), median pre- versus postoperative scores were 132 (101-215) versus 103 (70-156) for Apo10 (P < 0.0001) and 140 (102-212) versus 115 (84-187) (P < 0.0001) for TKTL1. Following radical prostatectomy, 56 (77.7%) and 59 (81.9%) patients in the cohort of patients with blood collection before and after prostatectomy showed a decrease of Apo10 and TKTL1 expressing monocytes. TKTL1 and Apo10 did not show any correlation with known histopathologic and clinical risk parameters.

CONCLUSIONS

The present study demonstrates that surgical removal of the primary tumor leads to a significant decrease of Apo10 and TKTL1 expressing macrophages. This observation further encourages studies assessing the optimal clinical utility of EDIM-based detection of Apo10 and TKTL1 in patients with PC.

MARCKS promotes invasion and is associated with biochemical recurrence in prostate cancer

BACKGROUND

Overtreatment of low-grade prostate cancer is a recognised problem for clinicians and patients. However, under-treatment runs the risk of missing the opportunity for cure in those who could benefit. Identification of new biomarkers of disease progression, including metastases, is required to better stratify and appropriately treat these patients. The ability to predict if prostate cancer will recur is an important clinical question that would impact treatment options for patients. Studies in other cancers have associated MARCKS with metastasis.

METHODS

Tissue microarrays of local prostatectomy samples from a cohort of biochemical recurrent and non-biochemical recurrent tumours were assayed for MARCKS protein expression. Prostate cancer cell lines were transfected with siRNA targeting MARCKS or a control and functional endpoints of migration, invasion, proliferation, viability and apoptosis were measured. Actin was visualised by fluorescent microscopy and evidence of a cadherin switch and activation of the AKT pathway were assayed.

RESULTS

MARCKS was upregulated in biochemical recurrent patients compared to non-biochemical recurrent. Knockdown of MARCKS reduced migration and invasion of prostate cancer cells, reduced MMP9 mRNA expression, as well as decreasing cell spreading and increased cell:cell adhesion in prostate cancer cell colonies. Knockdown of MARCKS had no effect on proliferation, viability or apoptosis of the prostate cancer cells.

CONCLUSIONS

In conclusion, MARCKS promotes migration and invasion and is associated with biochemical recurrence in localised prostate cancer tumours. The mechanisms by which this occurs have yet to be fully elucidated but lack of a cadherin switch indicates it is not via epithelial-to-mesenchymal transition. Actin rearrangement indicates that MARCKS promotes invasion through regulating the architecture of the cell.

Preoperative Multiparametric Magnetic Resonance Imaging Predicts Biochemical Recurrence in Prostate Cancer after Radical Prostatectomy

Objectives

To evaluate the utility of preoperative multiparametric magnetic resonance imaging (MP-MRI) in predicting biochemical recurrence (BCR) following radical prostatectomy (RP).

Materials/Methods

From March 2007 to January 2015, 421 consecutive patients with prostate cancer (PCa) underwent preoperative MP-MRI and RP. BCR-free survival rates were estimated using the Kaplan-Meier method. Cox proportional hazards models were used to identify clinical and imaging variables predictive of BCR. Logistic regression was performed to generate a nomogram to predict three-year BCR probability.

Results

Of the total cohort, 370 patients met inclusion criteria with 39 (10.5%) patients experiencing BCR. On multivariate analysis, preoperative prostate-specific antigen (PSA) (p = 0.01), biopsy Gleason score (p = 0.0008), MP-MRI suspicion score (p = 0.03), and extracapsular extension on MP-MRI (p = 0.03) were significantly associated with time to BCR. A nomogram integrating these factors to predict BCR at three years after RP demonstrated a c-index of 0.84, outperforming the predictive value of Gleason score and PSA alone (c-index 0.74, p = 0.02).

Conclusion

The addition of MP-MRI to standard clinical factors significantly improves prediction of BCR in a post-prostatectomy PCa cohort. This could serve as a valuable tool to support clinical decision-making in patients with moderate and high-risk cancers.

The role of prostate-specific antigen in light of new scientific evidence

OBJECTIVE

Review the scientific evidence acquired in recent years on Prostate-Specific Antigen (PSA).

ACQUISITION OF EVIDENCE

Analysis of the available evidence on the current role of PSA, according to a panel of experts who recorded their experience on the subject.

SUMMARY OF THE EVIDENCE

Currently, PSA cannot be considered solely an indicator of the presence or absence of prostate cancer. Rather, the determination of PSA assists the urologist in indicating the most appropriate treatment for a patient with benign prostatic hypertrophic (BPH), as well as in suspecting a prostatic tumour when the PSA reading increases >0,3 ng/ml, in patients treated with 5-alpha-reductase inhibitor, over the reading achieved at six months of having initiated this treatment. Moreover, PSA is a key factor in the follow-up of patients with prostate adenocarcinoma who undergo surgery, radiation therapy or minimally invasive techniques. PSA helps to define biochemical recurrence, suggest the existence of a local or distal recurrence and propose or rule out adjuvant therapies.

CONCLUSIONS

New data on the current role of PSA in the management of patients treated for BPH and/or prostate cancer should be taken into account.

Circulating tumor cells as a marker of response: implications for determining treatment efficacy and evaluating new agents

PURPOSE OF REVIEW

To assess the current and future potential of using circulating tumor cells (CTC) as a biomarker to assess staging/prognosis and treatment efficacy.

RECENT FINDINGS

The shedding of prostate cancer cells by the primary tumor into the circulation can occur very early in the disease process but the detection of CTC at the time of initial presentation is not necessarily a poor prognostic. Furthermore, some patients who have undergone a radical prostatectomy and have no evidence of disease for 5 years still have detectable tumor cells in their bone marrow. In some cases these dormant tumor cells can eventually be activated and form a metastasis. In other situations the shed cells might contain aggressive stem-like cells. Overall, a pattern of an evolving genomic and molecular profile appears to be apparent over the course of initial dissemination to development of overt metastases. Clinically, several studies suggest that the enumeration of CTC prior to and during chemotherapy is predictive of the overall therapeutic response. Additionally, the absolute count or CTC threshold could be patient specific and not universal, suggesting the change in CTC count on a case-by-case basis may be more significant for patient management.

SUMMARY

CTC are clinically significant in the management of prostate cancer. However, to determine the true efficacy of CTC detection in the active clinical arena, coordinated multi-institutional studies with a standardized detection methodology need to be undertaken.

Genetic predisposition to early recurrence in clinically localized prostate cancer

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Currently available nomograms to predict preoperative risk of early biochemical recurrence (EBCR) after radical prostatectomy are solely based on classic clinicopathological variables. Despite providing useful predictions, these models are not perfect. Indeed, most researchers agree that nomograms can be improved by incorporating novel biomarkers. In the last few years, several single nucleotide polymorphisms (SNPs) have been associated with prostate cancer, but little is known about their impact on disease recurrence. We have identified four SNPs associated with EBCR. The addition of SNPs to classic nomograms resulted in a significant improvement in terms of discrimination and calibration. The new nomogram, which combines clinicopathological and genetic variables, will help to improve prediction of prostate cancer recurrence.

OBJECTIVES

To evaluate genetic susceptibility to early biochemical recurrence (EBCR) after radical prostatectomy (RP), as a prognostic factor for early systemic dissemination. To build a preoperative nomogram to predict EBCR combining genetic and clinicopathological factors.

PATIENTS AND METHODS

We evaluated 670 patients from six University Hospitals who underwent RP for clinically localized prostate cancer (PCa), and were followed-up for at least 5 years or until biochemical recurrence. EBCR was defined as a level prostate-specific antigen >0.4 ng/mL within 1 year of RP; preoperative variables studied were: age, prostate-specific antigen, clinical stage, biopsy Gleason score, and the genotype of 83 PCa-related single nucleotide polymorphisms (SNPs). Univariate allele association tests and multivariate logistic regression were used to generate predictive models for EBCR, with clinicopathological factors and adding SNPs. We internally validated the models by bootstrapping and compared their accuracy using the area under the curve (AUC), net reclassification improvement, integrated discrimination improvement, calibration plots and Vickers' decision curves.

RESULTS

Four common SNPs at KLK3, KLK2, SULT1A1 and BGLAP genes were independently associated with EBCR. A significant increase in AUC was observed when SNPs were added to the model: AUC (95% confidence interval) 0.728 (0.674-0.784) vs 0.763 (0.708-0.817). Net reclassification improvement showed a significant increase in probability for events of 60.7% and a decrease for non-events of 63.5%. Integrated discrimination improvement and decision curves confirmed the superiority of the new model.

CONCLUSIONS

Four SNPs associated with EBCR significantly improved the accuracy of clinicopathological factors. We present a nomogram for preoperative prediction of EBCR after RP.

A phase II clinical trial of neoadjuvant ketoconazole and docetaxel chemotherapy before radical prostatectomy in high risk patients

PURPOSE

Patients with high risk prostate cancer (prostate specific antigen greater than 20 ng/ml, Gleason score greater than 7, or clinical stage T2b or greater) have been shown to have a 30% to 40% biochemical recurrence rate after definitive local therapy. Looking for improvement on these outcomes, we conducted a phase II clinical trial examining the combination of ketoconazole and docetaxel in the neoadjuvant setting before radical prostatectomy.

MATERIALS AND METHODS

A total of 22 patients with clinically localized, high risk prostate cancer were enrolled in the study. For 12 weeks they were treated with neoadjuvant docetaxel and ketoconazole, with dosing based on phase I data. Patients were monitored for tolerance of therapy and dosing adjustments were made for significant toxicities. Radical prostatectomy with extended lymph node dissection was subsequently performed and patients were followed postoperatively for biochemical recurrence.

RESULTS

At a median followup of 18 months 8 patients remained biochemically free of recurrence after surgery alone. An additional 6 patients received salvage therapy and had an undetectable prostate specific antigen. Of the 22 patients 16 experienced National Cancer Institute grade 3 or 4 toxicity at some point during the therapy. However, 16 patients completed all 4 cycles of chemotherapy.

CONCLUSIONS

Neoadjuvant ketoconazole combined with docetaxel has appreciable but acceptable toxicity with 73% of the patients completing all 4 courses of therapy. Of those who underwent radical prostatectomy 36% remained continuously biochemically free of recurrence at a median followup of 18 months.

Consensus on the utility of bone markers in the malignant bone disease setting

Biochemical markers of bone turnover provide insight into ongoing rates of skeletal metabolism and tumor-bone interactions in patients with malignant bone disease. This article reviews the available recent evidence assessing the potential of bone markers for detecting and monitoring malignant bone lesions in patients with advanced cancers, and for assessing overall skeletal health and response to antiresorptive therapies in patients at all stages of cancer progression. Most data thus far are for urinary N-terminal cross-linked telopeptide of type I collagen (NTX) in predicting risks of skeletal morbidity and death and monitoring response to zoledronic acid in patients with bone metastases. Ongoing studies are evaluating such correlations for other markers and therapies. Emerging evidence suggests that bone markers may help identify patients at high risk for bone metastasis or bone lesion progression, thereby allowing improved follow-up. Results from ongoing clinical trials evaluating such potential applications of bone markers are awaited.

Intakes of meat, fish, poultry, and eggs and risk of prostate cancer progression

BACKGROUND

Processed meat and fish have been shown to be associated with the risk of advanced prostate cancer, but few studies have examined diet after prostate cancer diagnosis and risk of its progression.

OBJECTIVE

We examined the association between postdiagnostic consumption of processed and unprocessed red meat, fish, poultry, and eggs and the risk of prostate cancer recurrence or progression.

DESIGN

We conducted a prospective study in 1294 men with prostate cancer, without recurrence or progression as of 2004-2005, who were participating in the Cancer of the Prostate Strategic Urologic Research Endeavor and who were followed for an average of 2 y.

RESULTS

We observed 127 events (prostate cancer death or metastases, elevated prostate-specific antigen concentration, or secondary treatment) during 2610 person-years. Intakes of processed and unprocessed red meat, fish, total poultry, and skinless poultry were not associated with prostate cancer recurrence or progression. Greater consumption of eggs and poultry with skin was associated with 2-fold increases in risk in a comparison of extreme quantiles: eggs [hazard ratio (HR): 2.02; 95% CI: 1.10, 3.72; P for trend = 0.05] and poultry with skin (HR: 2.26; 95% CI: 1.36, 3.76; P for trend = 0.003). An interaction was observed between prognostic risk at diagnosis and poultry. Men with high prognostic risk and a high poultry intake had a 4-fold increased risk of recurrence or progression compared with men with low/intermediate prognostic risk and a low poultry intake (P for interaction = 0.003).

CONCLUSIONS

Our results suggest that the postdiagnostic consumption of processed or unprocessed red meat, fish, or skinless poultry is not associated with prostate cancer recurrence or progression, whereas consumption of eggs and poultry with skin may increase the risk.

(18)F-Choline PET/CT imaging of RECIST measurable lesions in hormone refractory prostate cancer

PURPOSE

Apply measurability criteria based on the response evaluation criteria in solid tumors (RECIST) to lesions found on (18)F-choline positron emission tomography (PET)/computerized tomography (CT) in patients with hormone refractory prostate cancer.

METHODS

Whole-body PET followed by CT or in-line PET/CT using 3.3-4 MBq/kg of (18)F-choline was performed prospectively on 30 patients with prostate cancer, castrate testosterone levels, and rising post-treatment prostate specific antigen (PSA) levels. Lesions demonstrating increased (18)F-choline uptake were classified as measurable or non-measureable based on RECIST.

RESULTS

Three patients were known previously to have RECIST measurable lesions, 10 patients had metastatic findings on radionuclide bone scan, and 17 patients had elevated serum PSA level as the only evidence of disease. Lesions demonstrating increased (18)F-choline uptake were found in 28 (93%) patients. Thirty-eight PET/CT lesions from 14 patients were measurable by RECIST. Lymph node maximum standardized uptake value (SUV(max)) correlated with lymph node diameter (Pearson r = 0.44, p < 0. 001). RECIST measurable lymph node SUV(max) was significantly higher than that of non-measurable nodes (8.1 vs. 3.7, p < 0.0001). Detection of skeletal, prostatic, or RECIST-compatible lesions was more likely with a PSA level greater than 4.0 ng/ml (Fisher exact p = 0.0005).

CONCLUSION

Lesions detected with (18)F-choline PET/CT are frequently measurable by RECIST at baseline. Therefore, it may be feasible to include comparisons to RECIST in evaluations of (18)F-choline as a therapeutic response marker for hormone refractory prostate cancer.

Review: Biological relevance of disseminated tumor cells in cancer patients

The prognosis of cancer patients is largely determined by the occurrence of distant metastases. In patients with primary tumors, this relapse is mainly due to clinically occult micrometastasis present in secondary organs at primary diagnosis but not detectable even with high resolution imaging procedures. Sensitive and specific immunocytochemical and molecular assays enable the detection and characterization of disseminated tumor cells (DTC) at the single cell level in bone marrow (BM) as the common homing site of DTC and circulating tumor cells (CTC) in peripheral blood. Because of the high variability of results in DTC and CTC detection, there is an urgent need for standardized methods. In this review, we will focus on BM and present currently available methods for the detection and characterization of DTC. Furthermore, we will discuss data on the biology of DTC and the clinical relevance of DTC detection. While the prognostic impact of DTC in BM has clearly been shown for primary breast cancer patients, less is known about the clinical relevance of DTC in patients with other carcinomas. Current findings suggest that DTC are capable to survive chemotherapy and persist in a dormant nonproliferating state over years. To what extent these DTC have stem cell properties is subject of ongoing investigations. Further characterization is required to understand the biology of DTC and to identify new targets for improved risk prevention and tailoring of therapy. Our review will focus on breast, colon, lung, and prostate cancer as the main tumor entities in Europe and the United States.

Endorectal and dynamic contrast-enhanced MRI for detection of local recurrence after radical prostatectomy

OBJECTIVE

The objective of our study was to evaluate the sensitivity and specificity of endorectal MRI combined with dynamic contrast-enhanced MRI to detect local recurrence after radical prostatectomy.

MATERIALS AND METHODS

A total of 51 patients who had undergone radical prostatectomy for prostatic adenocarcinoma 10 months to 6 years before underwent a combined endorectal coil MRI and dynamic gadolinium-enhanced MRI before endorectal sonographically guided biopsy of the prostatic fossa. The MRI combined with MR dynamic imaging results were correlated with the presence of recurrence defined as a positive biopsy result or reduction in prostate-specific antigen level after radiation therapy.

RESULTS

Overall data of 46 (25 recurred, 21 nonrecurred) out of 51 evaluated patients were analyzed. All recurrences showed signal enhancement after gadolinium administration and, in particular, 22 of 24 patients (91%) showed rapid and early signal enhancement. The overall sensitivity and specificity of MR dynamic imaging was higher compared with MRI alone (88%, [95% CI] 69-98% and 100%, 84-100% compared with 48%, 28-69% and 52%, 30-74%). MRI combined with dynamic imaging allowed better identification of recurrences compared with MRI alone (McNemar test: chi-square(1) = 16.67; p = < 0.0001).

CONCLUSION

MRI combined with dynamic contrast-enhanced MRI showed a higher sensitivity and specificity compared with MRI alone in detecting local recurrences after radical prostatectomy.

Promoter hypermethylation in circulating blood cells identifies prostate cancer progression

Promoter hypermethylation of circulating cell DNA has been advocated as a diagnostic marker for prostate cancer, but its prognostic use is currently unclear. To assess this role, we compared hypermethylation of circulating cell DNA from prostate cancer patients with (Group 1, n = 20) and without (Group 2, n = 22) disease progression and age-matched controls (benign prostatic hyperplasia, Group 3, n = 22). We measured hypermethylation of 10 gene promoters in 2 sequential venous samples, obtained at diagnosis and during disease progression (median time, 15 months later). Matched time samples were obtained in the nonprogressing patients. We found that more hypermethylation was detected in the diagnostic sample from the patients with cancer than in controls for GSTP1, RASSF1 alpha, APC and RAR beta (p < 0.0001). Patients undergoing disease progression had a significant increase in methylation levels of these 4 genes when compared to the other patients (p < 0.001). Patients at risk of disease progression have higher detectable concentrations of circulating cell hypermethylation, than those without progression. The extent of this hypermethylation increases during disease progression and can be used to identify the extent and duration of treatment response in prostate cancer.

ProstaScint and its role in the diagnosis of prostate cancer

Cancer of the prostate is the most common cancer in males accounting for 33% of newly diagnosed cases. It is the second leading cause of cancer death in American males. The prevalence of prostate cancer increases most rapidly with age and the incidence (unlike other cancers) continues to rise with advancing age. Death due to this cancer is almost invariably the result of failure to control metastatic disease. In addition, several studies have demonstrated that over 30% of patients will experience biochemical recurrence after surgery with long-term (more than 10 years) follow-up. Information regarding the location of the cancer is critical to the success of initial therapy when deciding between local versus systemic treatment options in the newly diagnosed patient. For patients who have already undergone definitive treatment, the localization of recurrent tumor, evidenced by an elevation of prostate-specific antigen, is difficult unless the tumor burden is large enough to be detected on conventional radiographic studies or digital rectal examination and prostatic fossa biopsy. ProstaScint is a diagnostic tool used to detect metastatic prostate cancer in lymph nodes or other sites. This article provides an overview on the uses of ProstaScint in the assessment of patients with recurrent or metastatic prostate cancer.

Imaging in Oncology from The University of Texas M. D. Anderson Cancer Center: Diagnosis, Staging, and Surveillance of Prostate Cancer

OBJECTIVE

The purpose of this article is to discuss the epidemiology, risk factors, and presentation of prostate cancer. After reviewing the prostate anatomy, the article will show how imaging plays an important role in establishing the diagnosis, staging, and monitoring the therapeutic response in prostate cancer, with a focus on adenocarcinomas.

CONCLUSION

Imaging studies, in the appropriate laboratory and clinical context, contribute essential information that enhances the capacity to provide individualized risk stratification, a suitable treatment strategy, and monitoring for the patient with prostate cancer.

The spectrum of prostate cancer care: From curative intent to palliation

Prostate cancer is one of the most prevalent malignancies affecting men in the developed world. A spectrum of disease states exists and management is tailored to individual patients. Increasing public awareness and prostate-specific antigen testing have led to earlier detection and the possibility of cure but have increased the risk of overtreatment of indolent disease. Advances in curative modalities have reduced side effects and offer patients a choice of treatments. Nonetheless, many need no intervention and may be safely treated with active monitoring. Choice and timing of therapy for locally advanced and recurrent disease are variable, with potential benefits of early intervention counterbalanced by side effects of treatment. Progress has been made in the management of advanced disease; skeletal-related events have been reduced and survival has been increased. This review examines the evidence and rationale behind the treatment options from curative intent to management of locally advanced disease and palliation of metastatic disease.

Expression of vascular endothelial growth factor (VEGF) in locally invasive prostate cancer is prognostic for radiotherapy outcome

PURPOSE

Vascular endothelial growth factor (VEGF) is an important hypoxia-inducible pro-angiogenic protein that has been linked with an adverse survival outcome after radiotherapy in other cancer types: we hypothesized that this may also occur in prostate cancer. A retrospective study was, therefore, carried out to evaluate the potential of tumor VEGF expression to predict radiotherapy outcome in patients with high-risk prostate cancer.

METHODS AND MATERIALS

Fifty patients with locally advanced (T3 N0 M0) tumors of Gleason score > or =6, and who received radiotherapy alone as primary treatment for their disease, were studied. Vascular endothelial growth factor expression was assessed on pretreatment diagnostic tumor biopsies using a semiquantitative immunohistochemical scoring system. The results were analyzed in relation to clinicopathologic factors and patient outcome including biochemical failure and disease-specific mortality.

RESULTS

High VEGF expression was associated with a poor prognosis: in univariate log rank analysis, VEGF was the only significant prognostic factor for disease-specific survival (p = 0.035). High VEGF expression also associated with increased Gleason score (p = 0.02), but not posttreatment biochemical failure.

CONCLUSION

High tumor expression of VEGF identified patients at high risk of failure of treatment with radiotherapy. These patients might benefit from additional treatment approaches incorporating anti-angiogenic or hypoxia-specific agents.

Advancing prostate cancer: treatment options for the urologist

Today's urologists often face the dilemma of how to treat patients who have advancing prostate cancer. The diversity of this patient population makes treatment decisions challenging. For over 60 years the mainstay of treatment for patients who have advancing prostate cancer has been androgen deprivation therapy. Now there are new chemotherapeutic options, novel hormone manipulations, and other adjunctive therapies available. Based on a case presentation, the authors have attempted to outline for the practicing urologist, a logical progression of treatment options for advancing prostate cancer.

Molecular load of pathologically occult metastases in pelvic lymph nodes is an independent prognostic marker of biochemical failure after localized prostate cancer treatment

PURPOSE

Thirty percent of patients treated with curative intent for localized prostate cancer (PC) experience biochemical recurrence (BCR) with rising serum prostate-specific antigen (sPSA), and of these, approximately 50% succumb to progressive disease. More discriminatory staging procedures are needed to identify occult micrometastases that spawn BCR.

PATIENTS AND METHODS

PSA mRNA copies in pathologically normal pelvic lymph nodes (N0-PLN) from 341 localized PC patients were quantified by real-time reverse-transcriptase polymerase chain reaction. Based on comparisons with normal lymph nodes and PLN with metastases and on normalization to 5 x 10(6) glyceraldehyde-3'-phosphate dehydrogenase mRNA copies, normalized PSA copies (PSA-N) and a threshold of PSA-N 100 or more were selected for continuous and categorical multivariate analyses of biochemical failure-free survival (BFFS) compared with established risk factors.

RESULTS

At median follow-up of 4 years, the BFFS of patients with PSA-N 100 or more versus PSA-N less than 100 was 55% and 77% (P = .0002), respectively. The effect was greatest for sPSA greater than 20 ng/mL, 25% versus 60% (P = .014), Gleason score 8 or higher, 21% versus 66% (P = .0002), stage T3c, 18% versus 64% (P = .001), and high-risk group (50% v 72%; P = .05). By continuous analysis PSA-N was an independent prognostic marker for BCR (P = .049) with a hazard ratio of 1.25 (95% CI, 1.001 to 1.57). By categorical analysis, PSA-N 100 or more was an independent variable (P = .021) with a relative risk of 1.98 (95% CI, 1.11 to 3.55) for BCR compared with PSA-N less than 100.

CONCLUSION

PSA-N 100 or more is a new, independent molecular staging criterion for localized PC that identifies high-risk group patients with clinically relevant occult micrometastases in N0-PLN, who may benefit from additional therapy to prevent BCR.

[The role of PSA in diagnosis of prostate cancer and its recurrence]

Prostate specific antigen is the most important tumor marker of prostate cancer. PSA, in conjunction with digital rectal examination, is the first-line clinical tool for detection of prostate cancer. To improve its specificity PSA-density, PSA-ratio (fPSA/tPSA), PSA-velocity, and complexed PSA have been introduced into clinical praxis. The treatment of lower stage disease in younger men has resulted in a longer period of post-treatment cancer surveillance. Biochemical recurrence is an early indicator for clinical disease recurrence. PSA doubling time allows to distinguish between local and systemic progression and is also a valid predictor for distant metastasis and death of disease.

Retained Seminal Vesicles After Radical Prostatectomy: Frequency, MRI Characteristics, and Clinical Relevance

OBJECTIVE

Changes after radical prostatectomy (RP) may present potential pitfalls in the interpretation of pelvic MRI studies in post-RP patients. One such change is retained seminal vesicles (SVs). The purpose of this study was to characterize the MRI features and evaluate the frequency of retained SV remnants in patients after RP.

CONCLUSION

Retained SV remnants are a common finding after RP. Most are fibrotic distal tips. Recognition of SV remnants may prevent their misinterpretation as local recurrences.

Cyclooxygenase-2 (cox-2) expression is an independent predictor of prostate cancer recurrence

Lack of reliable prognostic markers hinders accurate prediction of disease progression in prostate cancer. The inducible proinflammatory enzyme cyclooxygenase-2 (COX-2) is implicated in prostate carcinogenesis, but its role in cancer progression is less clear. We examined whether COX-2 expression evaluated by immunohistochemistry (IHC) in radical prostatectomy (RP) specimens can predict biochemical recurrence. Archival prostate cancer specimens (n = 60) were obtained from patients who underwent RP, but had not received neoadjuvant hormonal therapy. Twenty-three patients had biochemical or clinical recurrence (mean time of recurrence: 38.2 months), and 37 patients were recurrence free (mean follow-up: 95 months). COX-2 expression was determined by IHC, using an anti-COX-2 antibody. Three individuals scored the staining independently, as high- or low-expression. COX-2 was expressed in prostate cancer cells, in adjacent normal glands and in specimens from patients who later progressed. At 62-months follow-up, COX-2 staining predicted progression with 82.4% sensitivity and 81.3% specificity. Sensitivity (86.4%) and specificity (86.7%) improved at > or = 100-months follow-up. In univariate analysis, Gleason score, preoperative PSA, extraprostatic extension, margin, seminal vesicle invasion, and high COX-2 expression were significant predictors of biochemical recurrence (p < 0.05). In multivariate analysis, preoperative PSA (hazard ratio/unit PSA change 1.080; p = 0.0036) and COX-2 expression (hazard ratio 16.442; p < 0.0001) were independent prognostic indicators. Patients with PSA > 7 ng/ml and high COX-2 expression had the highest probability of recurrence (Kaplan-Meier analysis). COX-2 expression is an independent predictor of prostate cancer progression following RP and underscores the significance of inflammatory factors in this process.

Increased expression and activity of CDC25C phosphatase and an alternatively spliced variant in prostate cancer

Alterations in the control of cell cycle progression have been implicated in a wide variety of malignant neoplasms, including prostate cancer. CDC25 phosphatases belong to the tyrosine phosphatase family and play a critical role in regulating cell cycle progression by dephosphorylating cyclin-dependent kinases at inhibitory residues. CDC25C plays an important role in the G2-M transition by activating Cdc2/Cyclin B1 complexes. To determine whether CDC25C activity is altered in prostate cancer, we have examined the expression of CDC25C and an alternatively spliced variant in human prostate cancer samples and cell lines. CDC25C protein is up-regulated in prostate cancer in comparison with normal prostate tissue and is present almost exclusively in its active dephosphorylated form. Expression of a biologically active alternatively spliced CDC25C isoform is also increased in prostate cancer and expression of alternatively spliced CDC25C is correlated to occurrence of biochemical (prostate-specific antigen) recurrence. We have also developed a quantitative reverse transcriptase-PCR analysis of Ki-67 expression as a method of measuring proliferative activity in prostate cancer from RNA samples. Based on this analysis of Ki67 expression, some but not all of this increase in CDC25C and its alternatively spliced variants is correlated with increased proliferation in prostate cancer. This data suggests that CDC25C might play an important role in prostate cancer progression and could be used to monitor and predict the aggressiveness of this disease.

2-[18F]fluoro-2-deoxyglucose positron emission tomography for the detection of disease in patients with prostate-specific antigen relapse after radical prostatectomy

EXPERIMENTAL DESIGN

Retrospective cohort study in 91 patients with prostate-specific antigen (PSA) relapse following prostatectomy, imaged with 2-[18F]fluoro-2-deoxyglucose positron emission tomography (FDG-PET) in a tertiary care cancer center between February 1997 and March 2003. Comparison was made with magnetic resonance imaging (n = 64), bone scan (n = 56), and computed tomography (n = 37). The standard of reference included biopsy or clinical and imaging follow-up. We calculated sensitivity and specificity of PET and correlated PET findings with PSA values, other clinical parameters, and conventional imaging, when available.

RESULTS

PET was true positive in 28 of 91 (31%) patients, showing isolated disease in the prostate bed (n = 3) or metastatic disease with (n = 2) or without (n = 23) simultaneous disease in the prostate bed. In detail, PET identified lesions in the prostate bed (n = 5, all true positives), bones (n = 22; 20 true positives, 2 false positives), lymph nodes (n = 7; 6 true positives, 1 likely false positive), and one liver metastasis. Mean PSA was higher in PET-positive than in PET-negative patients (9.5 +/- 2.2 versus 2.1 +/- 3.3 ng/mL). PSA of 2.4 ng/mL and PSA velocity of 1.3 ng/mL/y provided the best tradeoff between sensitivity (80%; 71%) and specificity (73%; 77%) of PET in a receiver operating curve analysis. Combination with other clinical parameters in a multivariate analysis did not improve disease prediction. There were only two patients in whom other imaging studies showed isolated local recurrence or metastatic disease.

CONCLUSIONS

FDG-PET detected local or systemic disease in 31% of patients with PSA relapse referred for this test. There is a link to tumor burden and tumor biology in that the probability for disease detection increased with PSA levels.

SRC-3 is required for prostate cancer cell proliferation and survival

Prostate cancer is the most common cancer in men in America. Currently, steroid receptor coactivators have been proposed to mediate the development and progression of prostate cancer, at times in a steroid-independent manner. Steroid receptor coactivator-3 (SRC-3, p/CIP, AIB1, ACTR, RAC3, and TRAM-1) is a member of the p160 family of coactivators for nuclear hormone receptors including the androgen receptor. SRC-3 is frequently amplified or overexpressed in a number of cancers. However, the role of SRC-3 in cancer cell proliferation and survival is still poorly understood. In this study, we show that SRC-3 is overexpressed in prostate cancer patients and its overexpression correlates with prostate cancer proliferation and is inversely correlated with apoptosis. Consistent with patient data, we have observed that reduction of SRC-3 expression by small interfering RNA decreases proliferation, delays the G1-S transition, and increases cell apoptosis of different prostate cancer cell lines. Furthermore, with decreased SRC-3 expression, proliferating cell nuclear antigen and Bcl-2 expression, as well as bromodeoxyuridine incorporation in prostate cancer cells are reduced. Finally, knockdown of SRC-3 with inducible short hairpin RNA expression in prostate cancer cells decreased tumor growth in nude mice. Taken together, these findings indicate that SRC-3 is an important regulator of prostate cancer proliferation and survival.

Time and PSA threshold model prognosticates long-term overall and disease-specific survival in prostate cancer patients as early as 3 months after external beam radiation therapy

The specific aim of this analysis was to evaluate the capability of a time and prostate-specific antigen (PSA) threshold model to prognosticate overall survival (OS) and disease-specific survival (DSS) based on early PSA kinetics after radiotherapy for prostate cancer by retrospective review of outcomes in 918 patients. Crossing below analyzed PSA thresholds at specific defined time points reduced disease-specific death hazard ratios to relative to the cohort above threshold. The time and PSA threshold model demonstrates the ability to prognosticate OS and DSS as early as 3 months post-radiotherapy for prostate cancer.

Evaluation and Management of Prostate-specific Antigen Recurrence After Radical Prostatectomy for Localized Prostate Cancer

A radical prostatectomy has been established as one of the standard management options for localized prostate cancer. However, a substantial proportion of patients who undergo a radical prostatectomy develop prostate-specific antigen (PSA) recurrence which is commonly defined as a PSA cut-off point value of 0.2 ng/ml. Although the management of PSA recurrence after radical prostatectomy may depend on the site of recurrence, it is quite difficult to identify the recurrent lesion accurately based on the currently available imaging technology. Patients who have surgical margin involvement or a Gleason score < or =7 based on the radical prostatectomy specimens, who do not have nodal or seminal vesicle involvement, and who develop a PSA recurrence >1-2 years after surgery with a doubling time of >1 year, and whose pre-treatment PSA is < 1.0-1.5 ng/ml are considered to benefit from local treatment with at least 64 Gy of salvage radiotherapy. Patients with different characteristics are considered to have distant metastases or both local lesions and distant metastases, and thus may be candidates for hormonal manipulation rather than radiotherapy. Since local recurrent lesions are considered to be quite small at the early stage of PSA recurrence, hormonal manipulation may be sufficient to prevent disease progression instead of radiotherapy. However, the optimal type and timing of hormonal manipulation remain to be elucidated. As a result, no consensus regarding the treatment for PSA recurrence after radical prostatectomy has yet been reached.

Prostate cancer relapse after therapy with curative intention: a diagnostic and therapeutic dilemma

Prostate cancer is the most common malignant disease and second in causes of cancer death among men in Western Europe and North America. Despite improved surgical and irradiation techniques tumor relapse after curatively intended therapy is not uncommon. Due to the difficulty in discriminating local and systemic progression, it is often difficult to decide what this means for the patient and what kind of second-line treatment has to be given. Modern imaging techniques (MRI with endorectal coil, Choline-PET-CT, ProstaScint-Scan) are used for diagnosis of prostate cancer relapse. Nevertheless, early detection of local tumor relapse and likewise the detection of disseminated tumor cells often fails. To differentiate between local and systemic progression, prognostic factors of the primary tumor (grading, surgical margins, infiltration of the seminal vesicles, lymph node metastases) and PSA kinetics are used. The time from initial treatment to biochemical relapse and PSA doubling time are of highest prognostic relevance. Local progression allows second-line local treatment with potentially curative results (local irradiation after radical prostatectomy, salvage-surgery / cryotherapy / HIFU after irradiation), while in the case of systemic progress a palliative systemic therapy (hormonal treatment, chemotherapy, bisphosphonates) is indicated. Before deciding on the most appropriate therapy, prognostic factors and the patient's individual situation (co-morbidity, life expectancy, individual wishes) should be taken into account.

Decreased -Methylacyl CoA Racemase Expression in Localized Prostate Cancer is Associated with an Increased Rate of Biochemical Recurrence and Cancer-Specific Death

Alpha-methylacyl CoA racemase (AMACR) is overexpressed in prostate cancer relative to benign prostatic tissue. AMACR expression is highest in localized prostate cancer and decreases in metastatic prostate cancer. Herein, we explored the use of AMACR as a biomarker for aggressive prostate cancer. AMACR protein expression was determined by immunohistochemistry using an image analysis system on two localized prostate cancer cohorts consisting of 204 men treated by radical prostatectomy and 188 men followed expectantly. The end points for the cohorts were time to prostate-specific antigen (PSA) failure (i.e., elevation >0.2 ng/mL) and time to prostate cancer death in the watchful waiting cohort. Using a regression tree method, optimal AMACR protein expression cut-points were determined to best differentiate prostate cancer outcome in each of the cohorts separately. Cox proportional hazard models were then employed to examine the effect of the AMACR cut-point on prostate cancer outcome, and adjusted for clinical variables. Lower AMACR tissue expression was associated with worse prostate cancer outcome, independent of clinical variables (hazard ratio, 3.7 for PSA failure; P = 0.018; hazard ratio, 4.1 for prostate cancer death, P = 0.0006). Among those with both low AMACR expression and high Gleason score, the risk of prostate cancer death was 18-fold higher (P = 0.006). The AMACR cut-point developed using prostate cancer-specific death as the end point predicted PSA failures independent of Gleason score, PSA, and margin status. This is the first study to show that AMACR expression is significantly associated with prostate cancer progression and suggests that not all surrogate end points may be optimal to define biomarkers of aggressive prostate cancer.

The fibroblast growth factor receptor-4 Arg388 allele is associated with prostate cancer initiation and progression

PURPOSE

Increased expression of fibroblast growth factors that can activate the fibroblast growth factor receptor-4 (FGFR-4) occurs in a substantial fraction of human prostate cancers in vivo. A germline polymorphism of the FGFR-4 gene resulting in expression of arginine at codon 388 (Arg388) is associated with aggressive disease in patients with breast and colon cancer. We therefore sought to determine whether the FGFR-4 Arg388 allele was associated with prostate cancer incidence and/or the occurrence of aggressive disease.

EXPERIMENTAL DESIGN

The FGFR-4 genotype of men undergoing radical prostatectomy and controls of the same race was determined and the genotype correlated with clinical and pathologic markers of disease aggressiveness. PNT1A cell lines expressing predominantly the FGFR-4 Arg388 or Gly388 allele were established, and cell migration and invasiveness of these cells were assessed by a wounding assay and by quantitative determination of invasion through Matrigel. Expression of urokinase-type plasminogen activator receptor was determined by quantitative RT-PCR and enzyme-linked immunoabsorption assay.

RESULTS

Homozygosity for the FGFR-4 Arg388 allele is strongly associated with the occurrence of prostate cancer in white men. The presence of the FGFR-4 Arg388 allele is also correlated with the occurrence of pelvic lymph node metastasis and biochemical (prostate-specific antigen) recurrence. Expression of FGFR-4 Arg388 in immortalized prostatic epithelial cells results in increased cell motility and invasion through Matrigel and was associated with increased expression of urokinase-type plasminogen activator receptor.

CONCLUSION

The FGFR-4 Arg388 allele is associated with both an increased incidence and clinical aggressiveness of prostate cancer and results in changes in cellular motility and invasiveness in immortalized prostate epithelial cells consistent with the promotion of metastasis.

Update on screening and early detection of prostate cancer

PURPOSE OF REVIEW

The aim of this review is to discuss advances in the field of screening and early detection of prostate cancer from papers published in 2003.

RECENT FINDINGS

The fall in distant prostate cancer mortality accounted for the overall decline in cause-specific mortality rates in the USA. In the European prostate cancer screening trial (European Randomized Study of Screening for Prostate Cancer), there is considerable stage migration towards organ-confined disease, which becomes more pronounced in the second screening round. The high sensitivity of the screening protocol (approximately 90%), low interval cancer rate (13-19%) and lead time estimates of 10 years and longer support a 4-year screening interval, current procedure in the European Randomized Study of Screening for Prostate Cancer trial. Advances achieved in research on the discriminative power of the free prostate-specific antigen forms, particularly pro-prostate-specific antigen, have progressed and may be introduced in cancer detection at low prostate-specific antigen levels rather than a further reduction of the current prostate-specific antigen threshold.

SUMMARY

Definitive evidence on the effectiveness of prostate cancer screening with prostate-specific antigen should come from the ongoing European Randomized Study of Screening for Prostate Cancer and Prostate, Lung, Colorectal and Ovary cancer trials, and should further elucidate the debate about the appropriate prostate-specific antigen threshold. Free prostate-specific antigen sub-forms offer prospects for prostate cancer detection at low prostate-specific antigen levels.

Androgen receptor polymorphisms and risk of biochemical failure among prostatectomy patients

BACKGROUND

Little is known about the role of inherited genotypes in prostate cancer (PC) progression. This prospective study evaluated the predictive value of androgen receptor (AR) polymorphisms (CAG and GGC repeats) among prostatectomy patients.

METHODS

We studied 354 patients registered at M. D. Anderson Cancer Center from 1991 to 2001. Kaplan-Meier and Cox proportional hazard analyses were used.

RESULTS

During an average follow-up of 56 months, 66 (19%) post-prostatectomy patients experienced biochemical failure (BF). Patients with higher CAG repeats (CAG > or = 24) had significantly longer BF-free survival (BFFS) than those with fewer repeats (CAG < or = 23) (P = 0.04). Higher CAG repeats were significantly associated with lower BF risk among Whites and African Americans. Among Whites, longer CAG repeats (relative risk (RR) = 0.45, P = 0.03) and Gleason score > or = 8 (RR = 19.33, P = 0.005) remained significant BFFS predictors in multivariate analysis. GGC repeats were not associated with BF.

CONCLUSIONS

Our data showed that an inherited polymorphism (CAG repeats) in the AR is related to differences in genetic susceptibility to BF, supporting the hypothesis that increased AR activity may play a role in PC progression.

Management of patients with an increasing prostate-specific antigen after radical prostatectomy

Since the late 1980s, early detection and monitoring of men for prostate cancer by serum prostate-specific antigen (PSA) measurement has resulted in an increase in the number of men presenting with a potentially curable disease. During the same time, in an attempt to provide a definitive cure, radical prostatectomy has been performed increasingly and now is regarded as the management option of choice for many patients with clinically localized prostate cancer. Radical prostatectomy involves the removal of all of the prostate tissue resulting in the serum PSA level to steadily decline to an undetectable level within 4 to 6 weeks after surgery. Despite improvements in surgical technique and a marked downward stage shift brought about by serum PSA testing, approximately 25% of men ultimately will experience a subsequent increase in serum PSA to a detectable level indicating disease recurrence after radical prostatectomy within 15 years. In this brief review, the factors associated with a high risk for disease recurrence after radical prostatectomy are discussed. Factors indicating whether the increasing serum PSA is caused by local recurrence or metastatic disease and the management options available to address serum PSA recurrence also are discussed.