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.

Prognostic relevance of positive urine markers in patients with negative cystoscopy during surveillance of bladder cancer.

BACKGROUND: The role of urine markers in the surveillance of patients with non-muscle invasive bladder cancer (NMIBC) is discussed extensively. In case of negative cystoscopy the additional prognostic value of these markers has not been clearly defined yet. The present study is the first systematic approach to directly compare the ability of a urine marker panel to predict the risk of recurrence and progression in bladder cancer (BC) patients with no evidence of relapse during surveillance for NMIBC. METHODS: One hundred fourteen patients who underwent urine marker testing during surveillance for NMIBC and who had no evidence of BC recurrence were included. For all patients cytology, Fluorescence-in-situ-hybridization (FISH), immunocytology (uCyt+) and Nuclear matrix protein 22 enzyme-linked immunosorbent assay (NMP22) were performed. All patients completed at least 24 months of endoscopic and clinical follow-up of after inclusion. RESULTS: Within 24 months of follow-up, 38 (33.0%) patients experienced disease recurrence and 11 (9.8%) progression. Recurrence rates in patients with positive vs. negative cytology, FISH, uCyt+ and NMP22 were 52.6% vs. 21.9% (HR = 3.9; 95% CI 1.75-9.2; p < 0.001), 47.6% vs. 25.0% (HR 2.7; 1.2-6.2; p = 0.01), 43.8% vs. 22.4% (HR 3.3; 1.5-7.6; p = 0.003) and 43.8% vs. 16.7% (HR 4.2; 1.7-10.8; p = 0.001). In patients with negative cytology, a positive NMP22 test was associated with a shorter time to recurrence (p = 0.01), whereas FISH or uCyt+ were not predictive of recurrence in these patients. In the group of patients with negative cytology and negative NMP22, only 13.5% and 5.4% developed recurrence and progression after 24 months. CONCLUSIONS: Patients with positive urine markers at time of negative cystoscopy are at increased risk of recurrence and progression. In patients with negative cytology, only NMP22 is predictive for recurrence. Patients with negative marker combinations including NMP22 harbour a low risk of recurrence. Therefore, the endoscopic follow-up regimen may be attenuated in this group of patients.

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.

Stepwise application of urine markers to detect tumor recurrence in patients undergoing surveillance for non-muscle-invasive bladder cancer.

BACKGROUND: The optimal use of urine markers in the surveillance of non-muscle-invasive bladder cancer (NMIBC) remains unclear. Aim of the present study was to investigate the combined and stepwise use of the four most broadly available urine markers to detect tumor recurrence in patients undergoing surveillance of NMIBC. PATIENTS AND METHODS: 483 patients with history of NMIBC were included. Cytology, UroVysion, fluorescence in situ hybridization (FISH), immunocytology (uCyt+), and NMP22 ELISA were performed before surveillance cystoscopy. Characteristics of single tests and combinations were assessed by contingency analysis. RESULTS: 128 (26.5%) patients had evidence of tumor recurrence. Sensitivities and negative predictive values (NPVs) of the single tests ranged between 66.4-74.3 and 82.3-88.2%. Two-marker combinations showed sensitivities and NPVs of 80.5-89.8 and 89.5-91.2%. A stepwise application of the two-test combinations with highest accuracy (cytology and FISH; cytology and uCyt+; uCyt+ and FISH) showed NPVs for high-risk recurrences (G3/Cis/pT1) of 98.8, 98.8, and 99.1%, respectively. CONCLUSIONS: Combinations of cytology, FISH, immunocytology, and NMP22 show remarkable detection rates for recurrent NMIBC. Stepwise two-test combinations of cytology, FISH, and immunocytology have a low probability of missing a high-risk tumor. The high sensitivities may justify the use of these combinations in prospective studies assessing the use of urine markers to individualize intervals between cystoscopies during follow-up.

Reliable housekeeping gene combination for quantitative PCR of lymph nodes in patients with prostate cancer.

BACKGROUND: To reliably compare the results of gene expression studies, the expression of the target gene should be normalized to the expression of a reference gene. For lymph node metastases of prostate cancer, no data on polymerase chain reaction (PCR) normalization have yet been reported. We aimed to determine the most reliable reference gene combination for this purpose in patients with prostate cancer. MATERIALS AND METHODS: Ten histologically- positive and ten negative lymph nodes of patients with prostate cancer were analyzed respectively. Expression of six candidate reference genes was comparatively assessed with quantitative Real-time PCR. The most stably-expressed gene combination was determined with geNorm software version 3.4. RESULTS: Hypoxanthine phosphoribosyltransferase-1 (HPRT1) and TATA box binding protein (TPB) were found to be the most stably expressed genes, with their combination having an expression stability value of M=0.17. CONCLUSION: Gene combination HPRT1 and TPB has the potential to be utilized for normalization in gene profiling assessment of metastatic and non-metastatic pelvic lymph node tissue from patients with prostate cancer.

Combined application of cytology and molecular urine markers to improve the detection of urothelial carcinoma.

BACKGROUND: The sensitivity of cytology for the detection of urothelial carcinoma (UC) is limited. Newer methods such as fluorescence in situ hybridization (FISH), immunocytology (uCyt+), and protein markers have been developed to improve urine-based detection of UC. As only little is known regarding the combined application of these markers, we investigated whether combinations of 4 of the most broadly available tests (cytology, FISH, uCyt+, and nuclear matrix protein 22 [NMP22-ELISA]) may improve their diagnostic performance. METHODS: The study was comprised of 808 patients who were suspected of having UC. All patients underwent urethrocystoscopy and upper urinary tract imaging and, in the case of positive findings, transurethral resection/biopsy. FISH, uCyt+, cytology, and NMP22-ELISA were performed in all patients. RESULTS: UC was diagnosed in 115 patients (14.2%). Cytology and FISH were found to be the single tests with the best overall performance (area under the curve [AUC], 0.78/0.79). Combinations of 2, 3, and 4 markers were found to increase the AUC to various extents compared with the use of single markers. Combining cytology and FISH improved the sensitivity and performance (AUC, 0.83) compared with the single tests and identified 12 tumors that were not detected by cytology alone. The percentage of WHO grade 3/carcinoma in situ tumors not detected by cytology was reduced by 62.5% when FISH was performed in cytology-negative patients. The addition of uCyt+ as a third test further improved performance (AUC, 0.86), whereas the addition of NMP22-ELISA was not found to have any additional influence on the performance of the test combination. CONCLUSIONS: The results of the current study support the combined use of urine markers and may form the basis of further studies investigating whether risk stratification based on urine marker combinations may individualize diagnostic algorithms and the surveillance of patients suspected of having UC.

Impact of different grades of microscopic hematuria on the performance of urine-based markers for the detection of urothelial carcinoma.

OBJECTIVE: To evaluate the performance of urine cytology (CYT), the UroVysion test [(fluorescence-in-situ-hybridization (FISH)], the uCyt+-test, and the nuclear matrix protein 22 ELISA (NMP22) at different grades of microscopic hematuria (HU) in a cohort of 2,365 patients suspicious for urothelial cell carcinoma (UCC). PATIENTS AND METHODS: A cohort of 2,365 consecutive patients suspected to have UCC underwent testing of at least 1 of the 4 noninvasive urine markers followed by cystoscopy, upper urinary tract imaging and, in case of suspicious findings, transurethral biopsy and/or resection of suspicious lesions. The grade of microscopic HU was determined by dipstick evaluation and urine microscopy and subdivided into 4 grades. The test results were compared with the HU status by contingency analysis and Cochran-Armitage test for trend separated for patients without evidence of UCC and with histologically proven UCC. RESULTS: In case of grade 0, I, II, and III HU, rates of false positive CYT were 13.0, 17.4, 16.3, and 19.5% (P = 0.02), false negative CYT distributed 37.9, 18.5, 20.0, and 15.5% (P = 0.0003). FISH was false positive in 16.7, 19.8, 19.8, and 23.3% (P = 0.051) and false negative in 42.7, 27.5, 25.9, and 25.0% (P = 0.1). The uCyt+ was false positive in 12.5, 16.9, 24.0 and 35.1% (P < 0.0001), and false negative in 57.1, 26.4, 31.5, and 12.7% (P = 0.0003). NMP22 was false positive in 35.3, 55.3, 75.2, and 79.7% (P < 0.0001) and false negative in 50.0, 36.2, 22.6, and 8.2% (P < 0.0001). CONCLUSION: The extent of microscopic HU significantly influences the performance of noninvasive urine markers for UC. False positive rates of CYT, uCyt+, and NMP22 significantly increase with the degree of HU whereas false negative results of CYT, uCyt+, and NMP22 are less frequent in patients with high grade microscopic HU. These results underline the relevance of the grade of HU for the appropriate interpretation of urine tests.

Evaluation of the KIT/stem cell factor axis in renal tumours.

AIM: To investigate the expression of the KIT/stem cell factor (SCF) axis in different renal cell carcinoma subtypes with regard to targeted therapies. MATERIALS AND METHODS: The expression of KIT and SCF were immunhistochemically assessed in 40 clear cell (ccRCC), 25 papillary (pRCC) and 19 chromophobe carcinomas (chRCC); 27 oncocytomas and 32 benign kidney parenchyma specimens differentiated into distal tubules (DT) and proximal tubules (PT). RESULTS: The expression of KIT was significantly higher in chRCC and oncocytoma compared to ccRCC and pRCC. All tumours exhibited a significant increase of membranous to cytoplasmic KIT expression, with the highest in ccRCC and pRCCs. SCF was expressed in all tumour subgroups, with the highest in oncocytomas and pRCC. SCF correlated positively with the cytoplasmic expression of KIT. A higher tumour stage correlated to lower KIT expression in ccRCC. CONCLUSION: Simultaneous expression of SCF and KIT in renal tumours, which seems to undergo a shift from the cytoplasm to the cell membrane, suggests paracrine and autocrine mechanisms in KIT activation, with different, as yet unknown, regulatory mechanisms in the different tumour entities.

Prospective assessment of histological serial sectioning of pelvic lymph nodes in prostate cancer: a cost-benefit analysis.

UNLABELLED: What's known on the subject? and What does the study add? Metastatic spread to the regional lymph nodes (LNs) is the single worst predictor of survival in prostate cancer. Knowledge of the LN status is crucial, as the treatment strategy is substantially altered in non-organ-confined disease. Current routine pathological protocols for evaluation of LN resection specimens do not demand a minimum of cross-sections per LN to be examined. Depending on the LN size, usually one to two sections are examined. This might lead to underestimation of the true metastatic burden. The present study shows that additional examination of cross-sections in pelvic LNs and applying prostate cancer-specific cytokeratine immunostaining does not lead to significantly increased detection of prostate cancer metastases. However, the work-load and the expenses were significantly higher compared with routine evaluation. OBJECTIVE: To evaluate the diagnostic gain in the detection of lymph node (LN) metastases of prostate cancer and the additional expenses of histological step-section analysis, including immunohistochemistry compared with routine histopathological evaluation. PATIENTS AND METHODS: In a prospective study, 19 patients with prostate cancer at high risk of LN metastases (>cT2c and/or PSA level of >20 ng/mL and/or Gleason score >8) underwent sentinel-guided LN resection. All palpable LNs were submitted to step-section analysis in 200-µm sections and concomitant immunohistochemical staining for cytokeratine (AE1/AE3), in addition to routine histopathology of one or two haematoxylin and eosin-stained sections per LN. The number of positive LNs and LN-positive patients for each method was compared; additional expenses in labour time and material for the extended evaluation were estimated. RESULTS: In all, 413 LNs were resected; 220 LNs were palpable and were included in the study. In seven of the 19 patients routine histopathological evaluation revealed LN metastases in 24 of 220 LNs (10.9%). Extended LN evaluation with step sectioning and cytokeratin immunohistochemistry did not reveal any additional patients with LN metastases. In one patient already diagnosed with LN metastases on routine histology, four additional LN metastases were detected upon extended LN evaluation. Three LNs of two patients, one of them pN0, contained disseminated tumour cells. Compared with conventional histological evaluation, serial-section analysis and immunohistochemistry increased expenses in materials and labour time 18.7-fold. CONCLUSIONS: Serial-section analysis seems to have only a minimal diagnostic gain; however, valid conclusions cannot be drawn, as not all LNs were submitted to extended evaluation. Considering the additional expenses, extensive LN evaluation in prostate cancer cannot generally be recommended.

XPA-210: a new proliferation marker determines locally advanced prostate cancer and is a predictor of biochemical recurrence.

PURPOSE: XPA-210 is a proliferation marker derived from Thymidine kinase-1. It is of clinical significance in kidney, breast, and bladder cancer. There are no data available for XPA-210 in prostate cancer (PC). Herein, we aim to determine the clinical usefulness of XPA-210 in PC. MATERIALS AND METHODS: In a retrospective study, cancer and benign tissue samples of 103 patients (median age 65 years, median PSA 9.04 ng/ml, median Gleason score 6) who underwent prostatectomy were constructed to a tissue micro array and stained for XPA-210. Semi-quantitative results were correlated with pathological and clinical data by Wilcoxon-Kruskall-Wallis and linear regression analysis. Expression levels in PC were correlated between the time of biochemical recurrence and the time to development of metastasis by the Kaplan-Meier method. Multivariate analysis was done to correlate those with the resection status. RESULTS: Mean staining score was 0.51-0.14 for tumor and benign tissue (P < 0.0001). Tumor staining score was significantly associated with Gleason score <6/≥6 (P < 0.0001) and T2/T >2 (P = 0.0007). When dividing the tumor score by the mean value, higher expression of XPA-210 was associated with a shorter time to biochemical recurrence (P = 0.003) and time to development of metastasis (P = 0.0061). Tumor staining (P = 0.0371) was an independent prognostic factor for biochemical relapse regardless of resection status. CONCLUSIONS: XPA-210 is a new tissue-based prognostic marker for prostate cancer histopathology. It reliably differentiates tumor and normal prostatic tissue predicting biochemical relapse and onset of metastatic disease. XPA-210 might be clinically useful for individual decision-making in PC-treatment.

Influence of renal excretory function on the performance of urine based markers to detect bladder cancer.

PURPOSE: In hematuria cases urine based tests are used to detect bladder cancer, although the diagnostic yield remains insufficient due to influencing variables, including urinary tract infection. Many patients are elderly with renal insufficiency and have proteinuria as an additional influencing factor. To our knowledge no data are available on the accuracy of urine based bladder cancer tests in conjunction with renal function. MATERIALS AND METHODS: Urine samples of 449 patients with hematuria and histology were included in analysis. Cytology, fluorescence in situ hybridization, immunocytology and nuclear matrix protein 22 assay were done. Renal function was classified as normal, impaired or severely impaired based on serum creatinine, the glomerular filtration rate and proteinuria. False-positive rates were statistically compared in regard to renal function. RESULTS: A total of 382 patients did not have bladder cancer. There was an increased false-positive rate for creatinine and the glomerular filtration rate. The nuclear matrix protein 22 test showed a 22.0% and 46.7% false-positive rate in the normal and limited function cohorts, respectively (p = 0.05). Similar trends were noted for proteinuria. Indeterminate significance was detected, separating those with severely impaired function for immunocytology and those in the normal group for fluorescence in situ hybridization (p = 0.08 and 0.06, respectively). Proteinuria was a significant factor for urine cytology with increased false-positive results in the absence of urinary tract infection (p = 0.0017 and 0.05, respectively). CONCLUSIONS: To our knowledge this is the first study of renal function and the accuracy of urine based bladder cancer markers. Renal function influences the diagnostic yield. A decreased glomerular filtration rate was associated with increased false-positive nuclear matrix protein 22 results while proteinuria decreased urine cytology specificity. Renal function should be considered when urine based bladder cancer tests are interpreted.

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.

Point-of-Care Tests for Bladder Cancer: The Influencing Role of Hematuria.

Introduction. Several point-of-care tests (POCT) are available for the diagnosis of bladder cancer (BC). We evaluate the impact of HU (hematuria) on performance of POCTs. Materials and Methods. Urine from 10 donors was diluted with blood from 0.5 to 0.00625%. BladderCheck(R), BTAstat(R), BCM(R), and BTA(R) tests were applied. Tests were additionally conducted in 54 patients with HU. HU was stratified according to the amount of erythrocytes (RBC)/µL using two systems: (1) no HU; mild microscopic HU; severe microscopic HU; gross HU; (2) I <25 RBCs; <250 II; ≥250 III. Results were compared to HU status and histopathology. Results. Gross HU became evident between 2090 RBCs/µL and 1065/µL. Addition of blood led to default tests in all 4: BladderCheck(R) 0.25%; BCM 0.025%, BioNexia 0.00625%, and BTAstat <0.00625%. Rates of false positives for BladderCheck, BTAstat, BCM, and BioNexia were 5.9, 11.8, 0, and 1.8% without HU and 0, 66.7, 44.4, and 66.7% with HU. BTAstat, BCM, and BioNexia were independently influenced by HU (P < 0.0002). Conclusions. NMP22-BladderCheck was most resistant to blood. The diagnostic yield of all others was significantly influenced by HU. A well-defined HU grading helps to define limits of HU for a reliable interpretation of BC-POCTs.

Differential Akt signalling in non-seminomatous testicular germ cell tumors.

AIM: To investigate the protein kinase B (Akt) signalling proteins phosphatase and tensin homolog (PTEN), phosphorylated-Akt (p-Akt) and cyclin-dependent kinase inhibitor 1B (p27(Kip1)) in non-seminomatous germ cell tumors (NST) with a view to future investigative approaches. MATERIALS AND METHODS: The expressions of PTEN, p-Akt and p27(Kip1) were immunohistochemically assessed in 17 teratomas, 27 embryonal cell carcinomas, 6 yolk sac tumors and 24 benign testicular parenchymas. The cytoplasmic and corresponding nuclear expressions were compared and correlated to tumor entity. RESULTS: PTEN was dramatically reduced in all the NST subgroups. Concentrated nuclear p27(Kip1) and loss of the cytoplasmic form was found in teratomas and embryonal cell carcinomas. Neither altered expression nor negative Akt regulation was found. The yolk sac tumors showed late cytoplasmic shift of PTEN and p27(Kip1). CONCLUSION: Both, the absence of overexpression of p-Akt and of negative correlations to PTEN and p27(Kip1) suggest that signalling of these parameters in NST might include additional mechanisms such as crosstalk to other pathways rather than classical Akt activation.

Impact of clinical parameters on the diagnostic accuracy of endorectal coil MRI for the detection of prostate cancer.

OBJECTIVES: Endorectal coil MRI (endoMRI) of the prostate is useful to evaluate tumor localization. There is little evidence on patient characteristics affecting its diagnostic performance. We evaluate the influence of clinical and histological parameters on the accuracy of endoMRI. METHODS: Sixty-nine patients with prostate cancer were included. After virtually dividing the prostate into pixels of 1 cm2, results of endoMRI were compared with those from prostatectomy specimens' whole-mount sections. Univariate and multivariate analyses were performed to calculate the impact of clinical and histological parameters on the number of appropriately described pixels. RESULTS: In 9, no tumor could be demonstrated by endoMRI. 48.3% of patients were staged correctly, 23.3% were over- and 28.3% understaged. Mean rates of correctly labeled pixels were 0.44 (± 0.04 SEM) for tumor and 0.90 (± 0.01) for benign segments. In univariate analysis, the rate of correctly labeled tumor segments showed significant positive correlations with Gleason score ≥7 and negative correlations with prostate weight and multifocality. The rate of correctly labeled benign segments showed significant negative correlation with tumor weight. All factors were independent variables in multivariate analysis. CONCLUSIONS: The reliability of endoMRI depends on clinical parameters. Higher Gleason scores, unifocal tumors and smaller prostate volumes ameliorate endoMRI performance.

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.

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.

Topographical sensitivity and specificity of endorectal coil magnetic resonance imaging for prostate cancer detection.

OBJECTIVES: Endorectal coil magnetic resonance imaging (EC-MRI) is useful to evaluate prostate cancer localization. Herein, we evaluate sensitivity and specificity of EC-MRI in different regions of the prostate by comparing the acquired images to whole-mount sections of the prostate after radical prostatectomy. METHODS: 69 patients with localized prostate cancer were included. After virtually dividing the prostate into 12 sectors, results of EC-MRI were compared to corresponding whole-mount sections by contingency analysis. Sensitivity and specificity were calculated for each of the 12 areas as well as for the dorsal and ventral region. RESULTS: Sensitivity right/left was dorsal apex/mid/base 41/41, 60/67 and 73/79%; ventral 33/52, 43/42 and 47/52%. Specificity right/left was dorsal apex/mid/base 92/89, 82/75 and 88/69%; ventral 100/100, 100/92 and 88/83%. Local sensitivity and specificity regarding dorsal versus ventral was 88/100 and 65/87%. CONCLUSIONS: Local sensitivity decreased from basodorsal to apicoventral direction, whereas local specificity increased in the same direction. Therefore, prostate cancers demonstrated by MRI are more prone to be detected in the basodorsal region, whereas less false-positive results are found in the apicoventral region. These variations in topographical specificity and sensitivity need to be considered before radical prostatectomy or MRI-guided biopsy.

Activation of mTOR in renal cell carcinoma is due to increased phosphorylation rather than protein overexpression.

The altered expression and activation of the mammalian target of rapamycin (mTOR) promotes the invasiveness and metastatic potential in a variety of malignancies. The aim of the present pilot study was to determine mTOR expression in clear cell renal cell carcinoma (RCC) and to evaluate mTOR activation and phosphorylation at Ser2448. Tissue microarray immunohistochemistry and Western blot analysis of tumor and benign tissue from 10 patients subjected to tumor nephrectomy were investigated. Staining of mTOR and phosphorylated-mTOR (p-mTOR) was documented and determined as percentage of the maximum. Western blots were evaluated densitometrically. Ratios of tumor versus benign tissue were calculated and compared by the Wilcoxon/Kruskal-Wallis test. Immunohistochemical expressions of mTOR and p-mTOR were 49 and 40% in benign renal parenchyma, whereas it was 20 and 42% in tumor tissue. Ratios of tumor versus benign tissue revealed a reduction to 0.44 for mTOR and corresponding elevation to 1.29 for p-mTOR (p<0.05). The rate of p-mTOR to mTOR was 1.19 in benign, whereas it was 5.30 in tumor tissue. Western blot densitometry detected lower expressions of mTOR in tumor compared to benign tissues. Ratio of p-mTOR to mTOR were significantly different in benign versus tumor tissue (0.86 vs. 1.37; p<0.04). The observation that RCC specimens exhibit higher levels of p-mTOR in RCC compared to benign renal parenchyma indicate the role of mTOR phosphorylation in RCC tumor development and progression. This study found a concomitant reduction of the RCC mTOR protein expression, which suggests that elevated levels of activated p-mTOR result predominantly from an increased mTOR phosphorylation rather than from protein overexpression. These pilot study results may contribute to the clarification of mTOR-pathway regulation processes in RCC on the way to the protein profiling-predicted targeted therapy.

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.