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

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

Galectin-1 and Galectin-3 mRNA expression in renal cell carcinoma.

BACKGROUND: Galectins are known to regulate cell differentiation and growth as well as cell adhesion and apoptosis. Galectins have been discussed as possible prognosticators for survival in renal cell cancer (RCC) and other urological tumors. They might also play an emerging role as possible new marker-proteins for RCC. In this study, we analyzed the expression of galectin-1 and galectin-3 mRNA in order to further investigate their clinical significance in RCC. METHODS: Tissue samples were obtained from 106 patients undergoing surgery for RCC. The expression of galectin-1 and galectin-3 mRNA in normal kidney and corresponding cancer tissue was analyzed using quantitative real time PCR. Differences in expression levels of paired tissue samples were assessed using paired two-sample tests. Associations of relative mRNA expression levels in tumor tissues with clinical findings were analyzed using univariate logistic regression. RESULTS: The expression of galectin-1 (p < 0.001) and -3 (p < 0.001) mRNA were significantly higher in RCC when compared to the adjacent normal kidney tissue. For clear cell RCC, an association of male gender with higher galectin-1 and galectin-3 mRNA expression (p = 0.054, p = 0.034) was detected. For all RCCs, galectin-1 mRNA expression failed to show a significant association with advanced disease as well as a higher rate of lymph node metastases (p = 0.058, p = 0.059). CONCLUSION: The mRNA expression of galectin-1 and galectin-3 is significantly increased in RCC cancer tissue. The higher mRNA expression in tumor tissue of male patients raises the question of a functional connection between galectins and the higher prevalence of RCC in men. Associations with advanced disease might lead to new ways of identifying patients at higher risk of recurrent disease and might even facilitate early metastasectomy with curative intent.

Exposed proliferation antigen 210 (XPA-210) in renal cell carcinoma (RCC) and oncocytoma: clinical utility and biological implications.

OBJECTIVE: • To determine the clinical role of the exposed proliferation antigen 210 (XPA-210) of the proliferation marker thymidine kinase 1 (TK1) in a large cohort of different renal cell carcinoma (RCC) types, oncocytomas and normal renal tissues samples, as TK1 is reported to be of clinical significance in several cancer entities and is suggested as a prognostic serum biomarker for RCC. PATIENTS AND METHODS: • Expressions of XPA-210 were determined immunohistochemically in 40 clear cell RCCs (ccRCC), 25 papillary RCCs (papRCC), 17 chromophobe RCC (chRCC), 27 oncocytomas and 64 normal renal parenchyma paraffin-embedded specimens. • Immunohistochemistry was performed with a monoclonal anti-XPA-210 antibody. Staining was measured by the percentage of positive cells. • Expression was compared between subgroups and correlated with respective clinical data using one-way analysis of variance with post hoc Tukey-Kramer analyses. RESULTS: • XPA-210 staining in the RCC subgroup was significantly different from the oncocytomas (mean [sem] 4.1 [0.4] vs 2.2 [0.4]; P = 0.004) and from normal renal tissue (1.0 [0.1]; P < 0.001], whereas oncocytomas did not differ from normal renal parenchyma staining (P = 0.18). • Subdivided into RCC groups, only ccRCC (mean [sem] 5.1 [0.6]; P < 0.001) and papRCC (4.4 [0.6]; P < 0.001) varied from normal renal parenchyma, whereas chRCC (1.4 [0.3]; P = 0.99) did not. • RCC XPA-210 staining was significantly associated with higher tumour stage (T = 3, P = 0.002) and grade (G = 3, P = 0.001). CONCLUSIONS: • The malignant character of RCC is reflected by higher XPA-210 expression as compared with oncocytomas and normal kidney. • The ccRCC and papRCC subgroups had higher XPA-210 levels. • XPA-210 could be considered a potential marker for the assessment of the proliferative activity in primary RCC.

High cytoplasmic expression of p27(Kip1) is associated with a worse cancer-specific survival in clear cell renal cell carcinoma.

UNLABELLED: What's known on the subject? and What does the study add? The loss of p27(Kip1) correlates with poor prognosis in various human cancers, and was postulated as a biomarker in RCC. Up to now p27(Kip1) analysis in RCC was focused on its nuclear localization. We confirmed higher p27(Kip1) expression in the nucleus and cytoplasm of RCC and correlated high cytoplasmic p27(Kip1) with an unfavourable clinic and a reduced survival. OBJECTIVES: To analyse the cytoplasmic and nuclear differences of p27(Kip1) expression and localization in benign and clear cell renal cell carcinoma (ccRCC) with regard to overall survival (OS) and cancer-specific survival (CSS). p27(Kip1) is considered to contribute to the progression of ccRCC and is targeted by next generation dual-therapies. PATIENTS AND METHODS: In 140 patients, ccRCC and corresponding benign kidney tissue were analyzed for nuclear and cytoplasmic staining of p27(Kip1) by immunohistochemistry using a tissue microarray technique. Staining intensity and percentage of positive stained cells are given as expression scores. p27(Kip1) expression was categorized as high if ccRCC tissue stained stronger than the respective level of the corresponding benign tissue and categorized as low if ccRCC tissue stained less than or equal to the corresponding benign tissue. Differences in OS and CSS were analyzed by log-rank analysis and expression levels were correlated with tumour and patient characteristics using Fisher's exact test. RESULTS: Cytoplasmatic (mean [sd]: 13.8% [1.2%] vs 10.7% [1.7%]; P= 0.04) and nuclear (mean [sd]: 75.6% [2.7%] vs 13.6% [2.1%]; P < 0.001) staining of p27(Kip1) were significantly stronger in ccRCC tissues compared to benign tissue. High cytoplasmic p27(Kip1) expression was significantly associated with a higher T and N stage, Fuhrman grade and the presence of metastatic disease (P < 0.001). The median follow-up time was 38.2 months. There was no difference in OS between the low and high expression groups, although CSS was significantly lower in patients with high cytoplasmic p27(Kip1) (P < 0.001) and CSS heavily tended to be lower in the nuclear low expression group (P= 0.069). CONCLUSIONS: High cytoplasmic p27(Kip1) levels in renal cancer tissues are associated with advanced disease and reduced cancer specific survival, whereas low nuclear expression levels appear to be beneficial. The present study corroborates the consideration of cytoplasmic p27(Kip1) for future diagnostic and targeted therapeutic approaches in RCC establishing a potential protective shift of p27(Kip1) from the cytoplasm to the nucleus.

Accurate risk assessment of patients with asymptomatic hematuria for the presence of bladder cancer.

PURPOSE: Bladder cancer is frequently diagnosed during a workup for hematuria. However, most patients with microscopic hematuria and many with gross hematuria are not appropriately referred to urologists. We hypothesized that in patients presenting with asymptomatic hematuria the risk of having bladder cancer can be predicted with high accuracy. Toward this end, we analyzed risk factors in patients with asymptomatic hematuria and developed a nomogram for the prediction of bladder cancer presence. METHODS: Data from 1,182 consecutive subjects without a history of bladder cancer undergoing initial evaluation for asymptomatic hematuria were collected at three centers. Clinical risk factors including age, gender, smoking status, and degree of hematuria were recorded. All subjects underwent standard workup including voided cytology, upper tract imaging, and cystourethroscopy. Factors associated with the presence of bladder cancer were evaluated by univariable and multivariable logistic regression analyses. The multivariable analysis was used to construct a nomogram. Internal validation was performed using 200 bootstrap samples. RESULTS: Of the 1,182 subjects who presented with asymptomatic hematuria, 245 (20.7 %) had bladder cancer. Increasing age (OR = 1.03, p < 0.0001), smoking history (OR = 3.72, p < 0.0001), gross hematuria (OR = 1.71, p = 0.002), and positive cytology (OR = 14.71, p < 0.0001) were independent predictors of bladder cancer presence. The multivariable model achieved 83.1 % accuracy for predicting the presence of bladder cancer. CONCLUSIONS: Bladder cancer presence can be predicted with high accuracy in patients who present with asymptomatic hematuria. We developed a nomogram to help optimize referral patterns (i.e., timing and prioritization) of patients with asymptomatic hematuria.

Severe paraneoplastic hypereosinophilia in metastatic renal cell carcinoma.

BACKGROUND: Renal cell carcinoma can cause various paraneoplastic syndromes including metabolic and hematologic disturbances. Paraneoplastic hypereosinophilia has been reported in a variety of hematologic and solid tumors. We present the first case in the literature of severe paraneoplastic hypereosinophilia in a patient with renal cell carcinoma. CASE PRESENTATION: A 46 year-old patient patient with a history of significant weight loss, reduced general state of health and coughing underwent radical nephrectomy for metastasized renal cell carcinoma. Three weeks after surgery, the patient presented with excessive peripheral hypereosinophilia leading to profound neurological symptoms due to cerebral microinfarction. Systemic treatment with prednisolone, hydroxyurea, vincristine, cytarabine, temsirolimus and sunitinib led to reduction of peripheral eosinophils but could not prevent rapid disease progression of the patient. At time of severe leukocytosis, a considerable increase of cytokines associated with hypereosinophilia was measurable. CONCLUSIONS: Paraneoplastic hypereosinophilia in patients with renal cell carcinoma might indicate poor prognosis and rapid disease progression. Myelosuppressive therapy is required in symptomatic patients.

XPA-210: a new proliferation marker to characterize tumor biology and progression of renal cell carcinoma.

PURPOSE: Recent lung cancer data have shown an association of XPA-210, a key peptide of thymidine kinase, with advanced disease. We thus assessed its proliferation status in primary (M0) and metastatic (M1) renal cell carcinoma (RCC). METHODS: Paraffin slides from 30 patients (mean age: 61.2 years; range: 42-84) with clear-cell RCC (M0 in 10; non-osseous M1 in 10; osseous M1 in 10) were T-matched for pT1/pT3. Corresponding malignant and benign renal parenchyma were immunohistochemically stained against XPA-210. Staining density was determined by a semi-quantitative score of positive cell shares. Staining intensity included the precise cellular location. RESULTS: XPA-210 occurred predominantly in the nucleus, with a minor cytoplasmatic component. RCC tissue showed higher density and stronger intensity than did benign renal tissue in both nucleus (P = 0.005) and cytoplasm (P = 0.01). Density and intensity were positively associated with tumor diameters ≤7 cm, whereas they tended to correlate inversely in tumors >7 cm (P 0.07). Density of stained cells was significantly higher in metastatic than in localized RCC in both nucleus and cytoplasm (P < 0.04). Non-osseous M1 tissue showed significantly higher nuclear and cytoplasmatic expression than did M0 tissue (P < 0.05), whereas osseous M1 tissue did not. CONCLUSIONS: In all RCC tissues, XPA-210 staining was significantly higher in the nucleus than in cytoplasm, potentially owing to large cytoplasmatic spaces as a characteristic histologic feature of clear-cell component. XPA-210 expression gradually increased from localized to metastatic disease, peaking in patients without bone involvement. Therefore, XPA-210 might aid the selection of appropriate adjuvant treatment in high-risk patients.

Flow matters: irrigation flow differs in flexible ureteroscopes of the newest generation.

The development of new-generation flexible ureteroscopes has improved diagnostic and therapeutic endourological procedures. Despite technical improvement irrigation flow and quality of vision is often unsatisfactory. This study describes inter-manufactural differences in the latest available flexible ureteroscopes in terms of irrigation flow in correlation to different deflection angles and the use of 1.9 Fr. stone baskets. Irrigation flow measurements were performed in five new-generation flexible ureterorenoscopes with 3.6 Fr. working channels: Wolf (Uretero-Renoscope 270°), Storz (Flex-X² and Flex-X(c)), ACMI (DUR-D) and Olympus (URF Type P5) in 0°, 90° and 180° deflection. All measurements were carried out five times with an empty working channel as well as with inserted 1.9 Fr. stone baskets. Mean flow rates with empty instruments (SD) counted 50 ml/min (0.8), 50 (1.0), 48 (1.7), 48 (1.6) and 44 (0.7) for ACMI, Wolf, Storz (FlexX² and Flex-X(c)), and Olympus, respectively. Stone baskets significantly reduced irrigation flows in all tested ureteroscopes (p < 0.05). In channels with inserted baskets, the highest flow rates were measured for ACMI and Wolf with 12 ml/min (0.7) each. The lowest reduction of flow rate was detected in the ACMI and the Wolf ureteroscope (76.0%, 38 ml/min each). Measurements after flexion showed no significant differences between the ureteroscopes. Latest generation of flexible ureteroscopes offer various new product developments, including excellent deflection capacities. This study showed inter-manufactural differences in terms of irrigation flow rates with either empty or occupied working channels resulting in significant alterations in endoscopic view.

Quantification of tumor cell burden by analysis of single cell lymph node disaggregates in metastatic prostate cancer.

BACKGROUND: The size of lymph node (LN) metastases in prostate cancer patients represents an important prognosticator, but histological work-up may not reflect the true extent of tumor invasion. We present a novel technique (1) to detect early tumor cell dissemination and (2) to quantify the true tumor burden. METHODS: Prospectively 232 LN of 20 consecutive patients with prostate cancer after lymph node dissection were longitudinally bisected, one half was subjected to single cell immunocytochemistry for pancytokeratine (CK), the other half underwent routine histopathological work-up and step section analysis. In immunocytochemistry, tumor cell density (TCD) was quantified by calculating the number of CK-positive cells/million leucocytes and compared to routine histopathology and step section analysis. RESULTS: Eight of 20 patients were positive in histopathology and step sectioning, but 14 of 20 patients were positive in single cell analysis. Twenty-five of 232 LN were positive in routine histopathology, whereas 52 of 232 LN were positive in single cell analysis. Median TCD in histopathologically positive LN was 3060.0 x 10(-6) and 9.9 x 10(-6) in histopathologically negative LN (P < 0.0001). Mean TCD of histopathologically negative LN of pN1 patients was significantly higher than the mean TCD of pN0 patients (P < 0.003). Mean TCD per patient correlated with serum-PSA (r(2) = 0.48, P < 0.006). CONCLUSIONS: Single cell analysis has an increased detection rate compared to routine histopathology and even to serial step section analysis. The method can detect early tumor dissemination and enables quantification of the tumor burden. The subgroup of histopathologically negative LN with CK-positive cells represents tumor cell dissemination not depicted histologically.

Expansion and differentiation of neural progenitors derived from the human adult enteric nervous system.

BACKGROUND & AIMS: Neural stem and progenitor cells from the enteric nervous system have been proposed for use in cell-based therapies against specific neurogastrointestinal disorders. Recently, enteric neural progenitors were generated from human neonatal and early postnatal (until 5 years after birth) gastrointestinal tract tissues. We investigated the proliferation and differentiation of enteric nervous system progenitors isolated from human adult gastrointestinal tract. METHODS: Human enteric spheroids were generated from adult small and large intestine tissues and then expanded and differentiated, depending on the applied cell culture conditions. For implantation studies, spheres were grafted into fetal slice cultures and embryonic aganglionic hindgut explants from mice. Differentiating enteric neural progenitors were characterized by 5-bromo-2-deoxyuridine labeling, in situ hybridization, immunocytochemistry, quantitative real-time polymerase chain reaction, and electrophysiological studies. RESULTS: The yield of human neurosphere-like bodies was increased by culture in conditional medium derived from fetal mouse enteric progenitors. We were able to generate proliferating enterospheres from adult human small or large intestine tissues; these enterospheres could be subcultured and maintained for several weeks in vitro. Spheroid-derived cells could be differentiated into a variety of neuronal subtypes and glial cells with characteristics of the enteric nervous system. Experiments involving implantation into organotypic intestinal cultures showed the differentiation capacity of neural progenitors in a 3-dimensional environment. CONCLUSIONS: It is feasible to isolate and expand enteric progenitor cells from human adult tissue. These findings offer new strategies for enteric stem cell research and future cell-based therapies.

mTOR and mTOR phosphorylation status in primary and metastatic renal cell carcinoma tissue: differential expression and clinical relevance.

PURPOSE: Impaired regulation of the Akt/mammalian target of rapamycin (mTOR) pathway has been implicated in mechanisms related to neoplastic transformation in renal cell cancer (RCC) through enhancement of cell proliferation and survival and mTOR activation has been reported to occur due to phosphorylation of mTOR. To further determine the relevance of mTOR expression and activation and to analyze their putative role as a biomarker for systemic treatment in metastatic RCC, we investigated the expression of mTOR and phospho(p)-mTOR in primary RCC and metastases and correlated levels with pathological variables and clinical outcome. METHODS: Tissue microarrays (TMA) from paraffin-embedded tissue from 342 patients with primary clear cell renal cell carcinoma and 90 patients undergoing surgical resection for metastases were immunohistochemically stained for mTOR and p-mTOR and expression was quantified with immunoreactivity scores. Clinical patient characteristics and follow-up were recorded. Comparative evaluation of protein expression levels and association of expression with clinical variables and survival was performed. RESULTS: mTOR staining revealed differential expression in benign, primary and RCC metastasis (average staining score: 1.64, 0.78, and 1.44, respectively). Average staining of p-mTOR was 0.99 in benign kidney tissue, 0.73 in primary RCC and 1.14 in RCC metastasis tissue. Elevated mTOR expression in primary RCC tissue was associated with the presence of tumor necrosis, while a high level of p-mTOR was significantly correlated with advanced T-stage, high Fuhrman grade, the presence of tumor necrosis and sarcomatoid features. An elevated ratio of p-mTOR/mTOR was significantly correlated with advanced stage and sarcomatoid histology. mTOR expression was not predictive of overall survival (OS), while high p-mTOR levels were associated with impaired OS (p = 0.0046) and cancer-specific survival (p = 0.0067). In univariate analysis, advanced stage (HR 3.78), high Fuhrman grade (HR 4.0), the presence of tumor necrosis (HR 1.99), and sarcomatoid features (HR 5.12) were significant predictors of OS. Moreover, elevated levels of p-mTOR (HR 1.67) and an elevated ratio of p-mTOR/mTOR ratio (HR 1.73) were significantly predictive of OS. In the multivariate regression model only the presence of locally advanced tumors (HR 2.44) was of independent prognostic value for OS, while there was a trend for impaired OS for patients with a high p-mTOR (HR 1.27, p = 0.21). CONCLUSIONS: Phosphorylated mTOR is differentially expressed in localized RCC and metastasis. Elevated phosphorylation of mTOR is associated with aggressive pathologic features and unfavorable outcome. Whether these findings portend to relevance for mTOR inhibition treatment for metastatic RCC should be objective of further investigations.

Can we still afford bladder cancer?

PURPOSE OF REVIEW: Bladder cancer is the most expensive tumor with regard to both costs per patient per year and lifetime costs per patient. Nonmuscle invasive tumors account for the highest share of the overall costs for bladder cancer. Costs for follow-up (excluding costs for reinterventions) compared with transurethral resection and cystectomy account for a considerably lower portion of the overall costs. RECENT FINDINGS: From an economic standpoint, the biggest potential for savings could, therefore, be in the treatment and re-treatment of nonmuscle invasive tumors. Cost reductions have already been demonstrated with a reduction of hospital admission for such treatments, use of photodynamic diagnosis supported transurethral resection to avoid residual tumors, and adjuvant chemoinstillation and immunoinstillation to prolong or prevent tumor recurrences. SUMMARY: Further cost reductions can be achieved with a centralization of patients undergoing cystectomy by shifting these patients to high-volume surgeons in high-volume hospitals, thereby reducing complications and length of hospital stay. In advanced stages predictive markers may identify suitable subgroups for molecular therapies and, therefore, avoid costs of inappropriate treatments.

PTEN and p27Kip1 are not downregulated in the majority of renal cell carcinomas--implications for Akt activation.

Activation of the PKB/Akt pathway is supposed to substantially contribute to the pathogenesis and progression of malignant disease. The present study aimed at determining the occurrence of an impaired PTEN and p27Kip1 expression alone or in combination in a renal cell carcinoma to further clarify the role of Akt-pathway-associated proteins for the development and/or progression of this malignant disease. By using tissue microarray analysis, tissue samples from renal cell cancers and the corresponding benign tissue samples were investigated for expression of the PTEN, pAkt and p27Kip1 protein by immunohistochemistry. Additionally, a Western blot and RT-PCR analysis was performed to verify the results obtained from the immunohistochemical approach and to further clarify the mechanisms underlying the regulation of both proteins in renal cell cancer. Western blot analysis revealed an overexpression of PTEN and p27Kip1 in renal cell cancer samples and a significantly elevated expression of both proteins when compared with the corresponding benign tissue (p<0.0001 and p<0.0005). The latter finding was confirmed by real-time RT-PCR (p<0.05 and p<0.01) and immunohistochemistry (p<0.001 and p<0.0001). PTEN and p27Kip1 expression were positively correlated with each other both in the tumour and benign tissue (p<0.001 and p<0.0001). We concluded that a strong expression of PTEN in renal cell cancer did not block the PI3K-mediated phosphorylation of Akt in the tumour specimens analysed. Furthermore, Akt activation may not result in a decreased p27Kip1, the latter being retained and overexpressed in the majority of renal cell cancers when compared with the corresponding benign renal parenchyma.

Activation of PI3K is associated with reduced survival in renal cell carcinoma.

OBJECTIVES: The epidermal growth factor receptor- (EGFR) activated phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB/Akt) pathway is associated with tumorigenesis and progression. The aims of the present study were to determine the expression patterns of Akt pathway parameters PI3K, phosphatase and tensin homolog (PTEN), phosphor-Akt (p-Akt) and their combination, for their possible prognostic value in renal cell carcinoma (RCC). PTEN dephosphorylates the liquid product of PI3K. METHODS: Tumor samples from 176 RCC patients were investigated for PTEN, p-Akt and PI3K expression by immunohistochemistry. Expression levels were correlated to clinical variables and postoperative outcome by uni- and multivariate statistical analysis. RESULTS: The various expression levels within the tumor samples were independent of histological grade and tumor stage, due to different levels of activation of the PI3K/p-Akt pathway. The activation of PI3K protein was found to be significantly associated with reduced survival times (p = 0.0304, multivariate analysis). Analysis of combined biomarker expressions showed that decreased long-term survival was correlated with PTEN low/p-Akt high expression (p < 0.05). CONCLUSIONS: Activation of the PI3K pathway is significantly associated with adverse clinical outcome in RCC. Analysis of biomarker combinations might identify high-risk patients and a subsequent need to adapt treatment modalities. Molecular pathways regulating PI3K activation appear to be promising targets for drug development in the clinical management of RCC patients.

Ex vivo γH2AX radiation sensitivity assay in prostate cancer: Inter-patient and intra-patient heterogeneity.

INTRODUCTION: The aim of the study is to assess inter-patient and intra-patient heterogeneity in tumour cell radiosensitivity using the ex vivo γH2AX assay in prostate cancer specimens. METHODS: Excised specimens from untreated prostate cancer patients were cultivated 24h in media, irradiated ex vivo and fixed after 24h. Residual γH2AX foci were counted and the slope of the dose response was calculated. Intra-patient heterogeneity was studied from three to seven different biopsies. RESULTS: In pathology-confirmed tumour samples from 21 patients the slope of residual γH2AX foci and radiation dose showed a substantial heterogeneity ranging from 0.82 to 3.17 foci/Gy. No correlation was observed between the slope values and the Gleason score (p=0.37), prostate specific antigen (p=0.48) and tumour stage (p=0.89). ANOVA indicated that only in 1 out of 9 patients, biopsies from different tumour locations yielded statistically significant differences. Variance component analysis indicated higher inter-patient than intra-patient variability. Bootstrap simulation study demonstrated that one biopsy is sufficient to estimate the mean value of residual γH2AX per dose level and account for intra-patient heterogeneity. CONCLUSIONS: In prostate cancer inter-patient heterogeneity in tumour cell radiation sensitivity is pronounced and higher than intra-patient heterogeneity supporting the further development of the γH2AX ex vivo assay as a biomarker for individualized treatment.

The thermoexpandable nitinol stent: a long-term alternative in patients without nephropathy or malignancy.

OBJECTIVE: The aim of this study was to investigate the long-term outcome of a thermoexpandable nickel-titanium nitinol ureteral stent (Memokath 051™) and to identify individual risk factors for failure. MATERIALS AND METHODS: This retrospective single-centre study included 125 patients who underwent implantation of the self-expandable Memokath 051 stent. Complications, indwelling time and reason for explantation were recorded. Analyses were stratified by gender, age, body mass index, American Society of Anesthesiologists score, estimated glomerular filtration rate (eGFR), side, localization and cause of the stricture. RESULTS: In total, 91 out of 125 patients (73%) were available for analysis. Median indwelling time was 355 days (range 7-2125 days). Most stents were removed because of dislocation (42%) or occlusion (40%). Stent removal was rarely performed because of infection (3%). Patients with sufficient renal function (eGFR ≥60 ml/min/1.73 m²) showed increased indwelling times compared with those with nephropathy (386 vs 317 days; p < 0.01). Patients with active malignant disease showed reduced patency time compared with strictures of benign origin (455 vs 190 days; p < 0.01). CONCLUSIONS: This thermoexpandable nitinol stent offers safe mid-term treatment of ureteric strictures, especially in patients without active malignancy and with good renal function.

PCA3 and PSA gene activity correlates with the true tumor cell burden in prostate cancer lymph node metastases.

BACKGROUND: Extent of pelvic lymph node (LN) dissemination is a critical prognostic feature for patients with prostate cancer (PCa) maintaining extended pelvic lymphadenectomy (LAD) as the gold standard for LN-staging. Unfortunately, conventional histopathological assessment may miss micrometastasis and recently presented immunocytochemical approach of the single cell analysis is still intricate. OBJECTIVE: To comparatively assess the potential of Prostate cancer gene 3 (PCA3) and prostate specific antigene (PSA) to perform as markers for tumor cell load. METHODS: Patients with high risk PCa for LN metastasis undergoing either a sentinel LN-guided staging LAD or retropubic radical prostatectomy with sentinel-guided pelvic LN dissection were included. LNs were investigated by routine histopathology. Tumor cell load was quantified by %immunocytochemistry. immunocytochemical single cell analysis. Gene activity was determined by qRT-PCR. RESULTS: Twenty four out of 226 LNs were positive in routine histopathology and 51 in single cell analysis. PSA mRNA level correlated with tumor cell density in patients with a positive immunocytochemistry. Gene activity of PCA3 was upregulated in metastatic LNs and correlated with tumor cell density in patients with tumor-invaded LNs as detected by immunocytochemistry. CONCLUSIONS: PCA3 gene expression discriminates LN metastasis and might outperform PSA gene activity in reflecting tumor cell burden in pelvic LNs of PCa patients.

γH2AX assay in ex vivo irradiated tumour specimens: A novel method to determine tumour radiation sensitivity in patient-derived material.

PURPOSE: To establish a clinically applicable protocol for quantification of residual γH2AX foci in ex vivo irradiated tumour samples and to apply this method in a proof-of-concept feasibility study to patient-derived tumour specimens. MATERIAL AND METHODS: Evaluation of γH2AX foci formation and disappearance in excised FaDu tumour specimens after (a) different incubation times in culture medium, 4Gy irradiation and fixation after 24h (cell recovery), (b) 10h medium incubation, 4Gy irradiation and fixation after various time points (double strand break repair kinetics), and (c) 10h medium incubation, irradiation with graded single radiation doses and fixation after 24h (dose-response). The optimised protocol was applied to patient-derived samples of seminoma, prostate cancer and glioblastoma multiforme. RESULTS: Post excision or biopsy, tumour tissues showed stable radiation-induced γH2AX foci values in oxic cells after >6h of recovery in medium. Kinetics of foci disappearance indicated a plateau of residual foci after >12h following ex vivo irradiation. Fitting the dose-response of residual γH2AX foci yielded slopes comparable with in situ irradiation of FaDu tumours. Significant differences in the slopes of ex vivo irradiated patient-derived tumour samples were found. CONCLUSION: A novel clinically applicable method to quantify residual γH2AX foci in ex vivo irradiated tumour samples was established. The first clinical results suggest that this method allows to distinguish between radiosensitive and radioresistant tumour types. These findings support further translational evaluation of this assay to individualise radiation therapy.

Muscle-invasive bladder cancer is characterized by overexpression of thymidine kinase 1.

OBJECTIVE: Thymidine kinases have an important role in the synthesis of DNA and exhibit high activity in rapidly proliferating cells. Thymidine kinase 1 (TK1) activity has been shown to be increased in various cancer types and proposed as a prognostic parameter. Aim of the present study was to investigate TK1 in muscle-invasive urothelial carcinoma (UC). METHODS: Corresponding UC and benign samples from paraffin embedded tissue of 111 patients treated with cystectomy for invasive UC from 1996 to 2006 were immunohistochemically (IHC) assessed for TK1. IHC expression patterns were evaluated in a semiquantitative fashion by 2 independent reviewers. Localization of staining was categorized into pure nuclear and additional cytoplasmic localization. Uni- and multivariate analyses were performed to assess differential expression in normal and UC tissue and to evaluate the diagnostic and predictive capability of TK1 by correlation to clinical data. To correlate TK1 expression with molecular subtypes of UC, analysis of TK1 RNA expression levels of the Cancer Genome Atlas UC cohort was performed. RESULTS: TK1 was significantly overexpressed in invasive UC, compared to benign urothelium (P<0.0001), and cytoplasmic expression was more often found in cancer tissue than in benign tissue (P = 0.0001). No correlations of TK1 protein expression patterns to standard histopathological determinants were detected. In univariate analysis, TK1 nuclear and cytoplasmic expression was associated with improved cancer-specific survival (P = 0.0119). However, only metastasis status and histologic grade were identified as independent predictors of cancer-specific survival in multivariate analysis. TK1 expression was merely found in the basal layers of benign urothelium. RNA overexpression of TK1 could be correlated to the biologically more aggressive basal UC subtype. CONCLUSIONS: TK1 expression is significantly different in invasive UC and benign urothelium, which underlines its potential as a diagnostic marker. Although TK1 is considered to be a marker of proliferation, and TK1 RNA overexpression is associated with an aggressive UC subtype, its capability as a predictive IHC biomarker for invasive UC remains limited.

Residual γH2AX foci after ex vivo irradiation of patient samples with known tumour-type specific differences in radio-responsiveness.

PURPOSE: To apply our previously published residual ex vivo γH2AX foci method to patient-derived tumour specimens covering a spectrum of tumour-types with known differences in radiation response. In addition, the data were used to simulate different experimental scenarios to simplify the method. MATERIALS AND METHODS: Evaluation of residual γH2AX foci in well-oxygenated tumour areas of ex vivo irradiated patient-derived tumour specimens with graded single doses was performed. Immediately after surgical resection, the samples were cultivated for 24h in culture medium prior to irradiation and fixed 24h post-irradiation for γH2AX foci evaluation. Specimens from a total of 25 patients (including 7 previously published) with 10 different tumour types were included. RESULTS: Linear dose response of residual γH2AX foci was observed in all specimens with highly variable slopes among different tumour types ranging from 0.69 (95% CI: 1.14-0.24) to 3.26 (95% CI: 4.13-2.62) for chondrosarcomas (radioresistant) and classical seminomas (radiosensitive) respectively. Simulations suggest that omitting dose levels might simplify the assay without compromising robustness. CONCLUSION: Here we confirm clinical feasibility of the assay. The slopes of the residual foci number are well in line with the expected differences in radio-responsiveness of different tumour types implying that intrinsic radiation sensitivity contributes to tumour radiation response. Thus, this assay has a promising potential for individualized radiation therapy and prospective validation is warranted.