Influence of age on false positive rates of urine-based tumor markers.

INTRODUCTION: Several influencing factors on false positive rates (FPRs) of urine-based tumor markers in the detection of urothelial cancer (UC) have been identified. We evaluated age as a possible influencing factor. METHODS: Urinary cytology (Cyt), UroVysion (FISH), ImmunoCyt (uCyt+) and NMP22 were determined in 1,554 patients suspicious for UC of the bladder before cystoscopy and in case of cancer detection before TURB. Additionally, upper urinary tract imaging was performed. Maker sensitivity, specificity and FPRs were evaluated in the entire cohort and in subgroups divided by age into <50, ≥ 50-70 and ≥ 70 years. Contingency tables and the Cochrane Armitage tests were used for statistical comparisons. RESULTS: UC was found in 377 and no UC in 1,177 (75 %) patients. A total of 336 patients were diagnosed with UC of the bladder and 41 with UC of the upper urinary tract. Overall sensitivity and specificity for Cyt were 82 and 82 %: for FISH, 73 and 79 % and for uCyt+, 79 and 75 %, respectively. For NMP22, regardless of the exclusion criteria they were 72 and 34 % and after exclusion of urinary tract infection (UTI) or prior to manipulation 46 and 86 %, respectively. Significantly higher FPRs were found with increasing age for Cyt (p = 0.001), a trend to higher FPRs for uCyt+ (p = 0.11) and almost no difference for FISH (p = 0.63). For NMP22, differences became significant after exclusion of patients with UTI or prior manipulation (p = 0.02). CONCLUSIONS: The results of the present study give evidence that false positive rates of Cyt and NMP22 increase with age indicating that age should be respected for their correct interpretation.

Prostatic peripheral nerve distribution may impact the functional outcome of nerve-sparing prostatectomy.

PURPOSE: To study microscopic patterns of remaining peripheral nerves (PN) after nerve-sparing (NS) radical prostatectomy (RP) and possible consequences for nerve preparation. METHODS: Specimens from 27 patients (7 = non-NSRP, 20 = unilateral NS) were examined. Sections were investigated for PN content by immunoassaying. 120 whole-mounted slides were divided into four sectors, and extracapsular nerves were counted; the mean posterior/anterior ratio was calculated. Calculated ratios were correlated with the respective volumes of prostatic tissue (PV). After dividing the patient cohort into two subgroups, shared by the median value of the posterior/anterior nerve ratios, the absolute PN contents on the anterior surface of the NS sides were compared. RESULTS: Anatomical posterior nerve percentage in non-NS aspects ranged from 0.0-100.0 to 26.7-94.6% with a mean of 66.60 ± 25.4% and 68.83 ± 16.0% (>/<200 µm, respectively). Individual ratios from two nerve categories showed significant correlation (P < 0.008). Mean posterior ratios were 83.04/79.68 and 39.21/56.00, respectively. After unilateral NS, 3.17-fold (2.25 vs. 0.71 nerves, P = 0.05) and 2.26-fold (21.54 vs. 9.53, P = 0.08) nerve fibers were resected in the anterior area in comparison with type A. After unilateral NS, the variation impact on the anterior nerve content of the NS side could be demonstrated. CONCLUSIONS: The amounts of nerves localized on the anterior prostate after RP vary interindividually. Saving only a minor part of the anterior areas may have an impact on the quantity of excised nerves adjacent to the specimen and impair postoperative functional results. Especially for those patients without a major posterolateral bundle distribution, surgeons should adapt the procedure and start nerve preservation more anteriorly to maximize the probability of satisfactory postoperative functional results.

Akt signalling parameters are different in oncocytomas compared to renal cell carcinoma.

PURPOSE: Renal oncocytomas are assigned as benign tumours, and their detailed molecular mechanism is poorly characterised. Activation of the PKB/Akt pathway is assumed to contribute to the pathogenesis and progression of malignant disease. For oncocytomas, hardly any data are available for Akt signalling parameters. Aim of the present work was to determine the alterations of Akt parameters PTEN, phosphorylated Akt (p-Akt) and p27(Kip1) in oncocytoma to better understand the dedifferentiation of renal tumours. METHODS: By tissue microarray analysis 15 oncocytoma, 18 clear cell renal cell carcinoma (ccRCC) and the corresponding benign tissue were investigated. Significant expression differences between PTEN, p-Akt and p27(Kip1) were determined by immunohistochemistry using One-way ANOVA with all pairs Tukey-Kramer as post hoc analyses. To investigate Akt parameter interactions in the oncocytoma, linear regression analyses were performed. RESULTS: Expression of all proteins was significantly different between the groups and in all groups the lowest for oncocytoma: PTEN: 32.9 ± 13.0 versus 75.5 ± 8.0 versus 123.7 ± 8.8; p < 0.001 for oncocytoma, benign parenchyma and ccRCC and 2.7 ± 1.2 versus 40.8 ± 9.5 versus 143.6 ± 12.2; p < 0.001 for p27(Kip1). p-Akt expression was significantly different between oncocytoma and ccRCC (67.3 ± 15.7 vs. 144.0 ± 26.6; p < 0.05). CONCLUSION: All three investigated parameters were the lowest in oncocytoma when compared to ccRCC. Expression of PTEN and p27(Kip1) seems to be exceedingly associated with malignant conditions of ccRCC. These findings might contribute to the understanding of tumorous signalling of the PKB/Akt axis in renal tumours.

Kidney-specific cadherin correlates with the ontogenetic origin of renal cell carcinoma subtypes: an indicator of a malignant potential?

INTRODUCTION AND OBJECTIVES: To evaluate retrospectively kidney-specific cadherin (Ksp-cad) expression in renal cell carcinoma (RCC) subtypes and oncocytoma in correlation with its ontogenetic origin of distal and proximal tubules and to correlate Ksp-cad expression with tumour characteristics. MATERIALS AND METHODS: Membranous and cytoplasmic expression of Ksp-cad was determined in 40 clear cell (ccRCC), 25 papillary (pRCC), 19 chromophobe carcinomas (chRCC), 27 oncocytomas (oncocytomas) (n = 111) and 32 benign kidney parenchyma specimens separated in distal tubules (DT) and proximal tubules (PT) by immunohistochemistry using tissue microarray technique. Staining intensity was quantified as a score ranging from 0 to 12. Comparison of data and correlation with tumour characteristics were done by Wilcoxon/Kruskal-Wallis tests (post hoc Tukey-Kramer analysis). RESULTS: In benign renal tissue, membranous and cytoplasmic expression of Ksp-cad in the DT was significantly higher than that in the PT (12.0 ± 0 vs. 5.2 ± 0.3 and 6.3 ± 0.5 vs. 0.0 ± 0.0, respectively; (P < 0.05)). Membranous KSP-cad expression was significantly higher in chRCC (5.2 ± 0.8) and oncocytomas (3.7 ± 0.4) than that in ccRCC (0.8 ± 0.2) and pRCC (1.4 ± 0.4; P < 0.05), while expression between oncocytomas and chRCC did not differ significantly. In RCC, Ksp-cad expression was significantly associated with higher T stage and the occurrence of synchronous metastasis (P < 0.05). Higher N stages and grading tended to correlate with a lower Ksp-cad expression. CONCLUSIONS: In this cohort, the origin of tumour subtypes-chRCC and oncocytomas develop from DT and ccRCC and pRCC from PT cells-is mirrored by the respective Ksp-cad expression. This raises the question whether DT-derived tumours have a less malignant potential than PT-derived tumours.

Evidence for PTEN-independent Akt activation and Akt-independent p27(Kip1) expression in advanced bladder cancer.

In the treatment of advanced bladder cancer (BC), attention has recently focused on small molecule therapy concerning EGFR and the downstream Akt signalling pathway. Cellular deregulation processes are poorly understood, and biological determinants for the selection of therapy and monitoring are currently not available. The proteins PTEN, p-Akt and p27(Kip1) are suggested to be potentially significant biomarkers of Akt signalling. In this study, we investigated the expression of these proteins in advanced BC. PTEN, p-Akt and p27(Kip1) expression was determined immunohistochemically in 86 T2-4 BC specimens using a tissue microarray technique. Staining was documented with regard to intensity, cellular frequency and a multiplied staining score. Staining characteristics of the three proteins were correlated by regression analysis with the parameters of tumour stage and grade. A positive correlation was observed in the expression scores of PTEN and p-Akt, p-Akt and p27(Kip1) as well as PTEN and p27(Kip1) (p<0.02 for all combinations). The positive correlation between PTEN and p-Akt resulted mainly due to the strong correlation of PTEN intensity with p-Akt (p=0.0003 and p=0.0006 to p-Akt frequency and intensity, respectively). A positive correlation between p-Akt and p27(Kip1) was noted for p-Akt frequency as well as intensity (p<0.05 for all combinations). The positive correlation between PTEN and p27(Kip1) resulted due to the correlation of PTEN intensity alone with p27(Kip1) (p<0.03 for p27(Kip1) frequency and intensity), whereas no significance was noted for PTEN frequency. No correlation was found between T or G and expression of the proteins. However, activation of Akt in BC is known to occur independently of PTEN protein loss and appears not to cause a decrease of p27(Kip1). However, a direct regulatory impact of PTEN on p27(Kip1) was found. PTEN intensity, rather than frequency, appears to be a superior biomarker. These results may provide information to support research into protein profiling-predicted targeted therapy for BC. Correlations to benign urothelium, superficial BC specimens and follow-up data remain to be investigated.