Item analysis of G8 screening in uro-oncologic geriatric patients.

INTRODUCTION/BACKGROUND: The G8 score is a widespread screening tool for geriatric frailty in oncology. The aim of this study was to evaluate the scores and relevance of G8 items in a standard screening of geriatric patients with uro-oncologic diseases to better understand the results of the assessment. METHODS: Eighty-two consecutive uro-oncologic geriatric patients aged 75 years and older were evaluated. All patients underwent a G8 screening that consisted of 8 items. Patients with a G8 score above 14 were considered geriatric "fit", while others were considered to be "frail". Overall results and single item scores were evaluated. Clinical data were gathered from patients' charts. RESULTS: The mean age of the patients was 82 years (min. 75-max. 102). In 36 of the patients, the G8 score indicated "no-frailty", and in 46 patients, the G8 score indicated "frailty". The mean G8 score was 12.9 (min 4-max 17 pts). Item analysis revealed that points were most often lost in items H (polypharmacy), P (comparison of health status to peers) and Age. Fifty-nine, 56 and 52 patients lost points on item Age, item H and item P, respectively. In contrast, the majority of patients reached the maximum score for nutritional items [i.e., items A (food intake), B (weight loss) and F (body mass index (BMI))]. For item A, 73 patients reached the maximum score; for item B, 62 patients reached the maximum score; and for item F, 72 patients reached the maximum score. There were no differences in this distribution pattern when comparing tumour entities, sex, and patients with local vs. metastatic disease. CONCLUSION: The present study revealed a high percentage of suspicious test results. Potential reasons for these findings include the low threshold of the G8 overall score and the fact that in some items, points were easily lost. Modifications of the test should be considered.

[Supplementary optical techniques for the detection of nonmuscle invasive bladder cancer]. / Unterstützende optische Verfahren zur Detektion nicht-muskelinvasiver Blasentumoren.

White light cystoscopy (WL) is the gold standard for the detection of bladder cancer. It can be performed using a rigid or flexible urethrocystoscope. With the more recent introduction of high definition (HD) techniques, WL cystoscopy has been decisively improved. Supplementary optical techniques are also used to improve the detection of bladder cancer. Among these are photodynamic diagnosis (PDD), narrow-band imaging (NBI), S­technologies of IMAGE1 S, optical coherence tomography (OCT), confocal laser endomicroscopy (CLE), and Raman spectroscopy. The aim of the present work is to introduce the techniques and to discuss their current role and future potential in the detection of bladder cancer.

Genetic immunization with mouse thyrotrophin hormone receptor plasmid breaks self-tolerance for a murine model of autoimmune thyroid disease and Graves' orbitopathy.

Experimental models of Graves' hyperthyroid disease accompanied by Graves' orbitopathy (GO) can be induced efficiently in susceptible inbred strains of mice by immunization by electroporation of heterologous human TSH receptor (TSHR) A-subunit plasmid. In this study, we report on the development of a bona fide murine model of autoimmune Graves' disease induced with homologous mouse TSHR A-subunit plasmid. Autoimmune thyroid disease in the self-antigen model was accompanied by GO and characterized by histopathology of hyperplastic glands with large thyroid follicular cells. Examination of orbital tissues showed significant inflammation in extra-ocular muscle with accumulation of T cells and macrophages together with substantial deposition of adipose tissue. Notably, increased levels of brown adipose tissue were present in the orbital tissue of animals undergoing experimental GO. Further analysis of inflammatory loci by 19 F-magnetic resonance imaging showed inflammation to be confined to orbital muscle and optic nerve, but orbital fat showed no difference in inflammatory signs in comparison to control ß-Gal-immunized animals. Pathogenic antibodies induced to mouse TSHR were specific for the self-antigen, with minimal cross-reactivity to human TSHR. Moreover, compared to other self-antigen models of murine Graves' disease induced in TSHR knock-out mice, the repertoire of autoantibodies to mouse TSHR generated following the breakdown of thymic self-tolerance is different to those that arise when tolerance is not breached immunologically, as in the knock-out models. Overall, we show that mouse TSHR A-subunit plasmid immunization by electroporation overcomes tolerance to self-antigen to provide a faithful model of Graves' disease and GO.

RAS pathway mutations as a predictive biomarker for treatment adaptation in pediatric B-cell precursor acute lymphoblastic leukemia.

RAS pathway mutations have been linked to relapse and chemotherapy resistance in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL). However, comprehensive data on the frequency and prognostic value of subclonal mutations in well-defined subgroups using highly sensitive and quantitative methods are lacking. Targeted deep sequencing of 13 RAS pathway genes was performed in 461 pediatric BCP-ALL cases at initial diagnosis and in 19 diagnosis-relapse pairs. Mutations were present in 44.2% of patients, with 24.1% carrying a clonal mutation. Mutation frequencies were highest in high hyperdiploid, infant t(4;11)-rearranged, BCR-ABL1-like and B-other cases (50-70%), whereas mutations were less frequent in ETV6-RUNX1-rearranged, and rare in TCF3-PBX1- and BCR-ABL1-rearranged cases (27-4%). RAS pathway-mutated cells were more resistant to prednisolone and vincristine ex vivo. Clonal, but not subclonal, mutations were linked to unfavorable outcome in standard- and high-risk-treated patients. At relapse, most RAS pathway mutations were clonal (9 of 10). RAS mutant cells were sensitive to the MEK inhibitor trametinib ex vivo, and trametinib sensitized resistant cells to prednisolone. We conclude that RAS pathway mutations are frequent, and that clonal, but not subclonal, mutations are associated with unfavorable risk parameters in newly diagnosed pediatric BCP-ALL. These mutations may designate patients eligible for MEK inhibitor treatment.

Genomic and transcriptional landscape of P2RY8-CRLF2-positive childhood acute lymphoblastic leukemia.

Children with P2RY8-CRLF2-positive acute lymphoblastic leukemia have an increased relapse risk. Their mutational and transcriptional landscape, as well as the respective patterns at relapse remain largely elusive. We, therefore, performed an integrated analysis of whole-exome and RNA sequencing in 41 major clone fusion-positive cases including 19 matched diagnosis/relapse pairs. We detected a variety of frequently subclonal and highly instable JAK/STAT but also RTK/Ras pathway-activating mutations in 76% of cases at diagnosis and virtually all relapses. Unlike P2RY8-CRLF2 that was lost in 32% of relapses, all other genomic alterations affecting lymphoid development (58%) and cell cycle (39%) remained stable. Only IKZF1 alterations predominated in relapsing cases (P=0.001) and increased from initially 36 to 58% in matched cases. IKZF1's critical role is further corroborated by its specific transcriptional signature comprising stem cell features with signs of impaired lymphoid differentiation, enhanced focal adhesion, activated hypoxia pathway, deregulated cell cycle and increased drug resistance. Our findings support the notion that P2RY8-CRLF2 is dispensable for relapse development and instead highlight the prominent rank of IKZF1 for relapse development by mediating self-renewal and homing to the bone marrow niche. Consequently, reverting aberrant IKAROS signaling or its disparate programs emerges as an attractive potential treatment option in these leukemias.

Prognostic value of rare IKZF1 deletion in childhood B-cell precursor acute lymphoblastic leukemia: an international collaborative study.

Deletions in IKZF1 are found in ~15% of children with B-cell precursor acute lymphoblastic leukemia (BCP-ALL). There is strong evidence for the poor prognosis of IKZF1 deletions affecting exons 4-7 and exons 1-8, but evidence for the remaining 33% of cases harboring other variants of IKZF1 deletions is lacking. In an international multicenter study we analyzed the prognostic value of these rare variants in a case-control design. Each IKZF1-deleted case was matched to three IKZF1 wild-type controls based on cytogenetic subtype, treatment protocol, risk stratification arm, white blood cell count and age. Hazard ratios for the prognostic impact of rare IKZF1 deletions on event-free survival were calculated by matched pair Cox regression. Matched pair analysis for all 134 cases with rare IKZF1 deletions together revealed a poor prognosis (P<0.001) that was evident in each risk stratification arm. Rare variant types with the most unfavorable event-free survival were DEL 2-7 (P=0.03), DEL 2-8 (P=0.002) and DEL-Other (P<0.001). The prognosis of each type of rare variant was equal or worse compared with the well-known major DEL 4-7 and DEL 1-8 IKZF1 deletion variants. We therefore conclude that all variants of rare IKZF1 deletions are associated with an unfavorable prognosis in pediatric BCP-ALL.

KRAS and CREBBP mutations: a relapse-linked malicious liaison in childhood high hyperdiploid acute lymphoblastic leukemia.

High hyperdiploidy defines the largest genetic entity of childhood acute lymphoblastic leukemia (ALL). Despite its relatively low recurrence risk, this subgroup generates a high proportion of relapses. The cause and origin of these relapses remains obscure. We therefore explored the mutational landscape in high hyperdiploid (HD) ALL with whole-exome (n=19) and subsequent targeted deep sequencing of 60 genes in 100 relapsing and 51 non-relapsing cases. We identified multiple clones at diagnosis that were primarily defined by a variety of mutations in receptor tyrosine kinase (RTK)/Ras pathway and chromatin-modifying genes. The relapse clones consisted of reappearing as well as new mutations, and overall contained more mutations. Although RTK/Ras pathway mutations were similarly frequent between diagnosis and relapse, both intergenic and intragenic heterogeneity was essentially lost at relapse. CREBBP mutations, however, increased from initially 18-30% at relapse, then commonly co-occurred with KRAS mutations (P<0.001) and these relapses appeared primarily early (P=0.012). Our results confirm the exceptional susceptibility of HD ALL to RTK/Ras pathway and CREBBP mutations, but, more importantly, suggest that mutant KRAS and CREBBP might cooperate and equip cells with the necessary capacity to evolve into a relapse-generating clone.

[Differential diagnosis of hematuria]. / Differenzialdiagnose der Hämaturie.

Hematuria is the main symptom of many urological and nephrological diseases. In the differential diagnostics a distinction is made between painful and pain-free and between macrohematuria which is visible to the naked eye and microhematuria which is not visible. The reasons for hematuria are basically renal (glomerular) and non-renal (non-glomerular) causes. In order not to overlook early symptoms of malignant and relevant benign diseases and also to avoid excessive diagnostic tests, a differentiated approach is necessary.

EMP1, a novel poor prognostic factor in pediatric leukemia regulates prednisolone resistance, cell proliferation, migration and adhesion.

Still 20% of pediatric acute lymphoblastic leukemia (ALL) patients relapse on or after current treatment strategies. Treatment failure is associated with resistance to prednisolone. We aimed to find new druggable targets that modulate prednisolone resistance. We generated microarray gene expression profiles of 256 pediatric ALL patient samples and identified a 3.4-fold increase in epithelial membrane protein 1 (EMP1) expression in in vitro prednisolone-resistant compared with -sensitive patients (P=0.003). EMP1 silencing in six precursor-B ALL (BCP-ALL) and T-ALL cell lines induced apoptosis and cell-cycle arrest leading to 84.1±4.5% reduction in survival compared with non-silencing control transduced cells (non-silencing control short hairpin, shNSC) (P=0.014). Moreover, EMP1 silencing sensitized to prednisolone up to 18.8-fold (P<0.001). EMP1 silencing also abrogated migration and adhesion to mesenchymal stromal cells (MSCs) by 78.3±9.0 and 29.3±4.1% compared with shNSC (P<0.05). We discovered that EMP1 contributes to MSC-mediated prednisolone resistance. Pathway analysis indicated that EMP1 signals through the Src kinase family. EMP1-high BCP-ALL patients showed a poorer 5-year event-free survival compared with EMP1-low patients (77±2 vs. 89±2%, P=0.003). Multivariate analysis taking along white blood cell count, age, prednisolone resistance and subtype identified EMP1 as an independent predictor for poor outcome in BCP-ALL (P=0.004, hazard ratio: 2.36 (1.31-4.25). This study provides preclinical evidence that EMP1 is an interesting candidate for drug development to optimize treatment of BCP-ALL.

[Prostate cancer]. / Prostatakarzinom.

For many clinical issues regarding prostate cancer magnetic resonance imaging (MRI) is gaining increasing importance for prostate diagnostics. The high morphological resolution of T2-weighted sequences is unsurpassed compared to other imaging modalities. It enables not only the detection and localization of prostate cancer but also allows the evaluation of extracapsular extensions. Functional MRI methods, such as diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI and proton magnetic resonance spectroscopy ((1)H-MRS) increase the specificity and to a lesser extent, the sensitivity of diagnostics. In accordance with the interdisciplinary S3 guidelines, prostate MRI is recommended for patients with at least one negative biopsy for cancer detection. According to the guidelines areas suspected of being cancerous should be selectively biopsied in addition to the systematic biopsy. The transmission of findings about the suspected tumor areas according to the structured PI-RADS classification system has proven its worth. The localization and staging of prostate carcinoma is best achieved with the help of MRI and is recommended in the S3 guidelines especially for tumors with a clinical stage cT3/4 or with a Gleason grading system score ≥8. In addition to these applications MRI is mainly used under study conditions for local recurrence or active surveillance.

Identification of novel NOTCH1 mutations: increasing our knowledge of the NOTCH signaling pathway.

BACKGROUND: Alterations in the NOTCH1 signaling pathway are found in about 60% of pediatric T-ALL, but its impact on prognosis remains unclear. PROCEDURE: We extended the previously published CoALL cohort (n = 74) to a larger cohort (n = 127) and additionally included 38 Argentine patients from ALL IC-BFM to potentially identify novel mutations and decipher a stronger discriminatory effect on the genotype/phenotype relationship with regard to early treatment response and long-term outcome. RESULTS: Overall, 101 out of 165 (61.2%) T-ALL samples revealed at least one NOTCH1 mutation, 28 of whom had combined NOTCH1 and FBXW7 mutations. Eight T-ALL samples (4.8%) exclusively revealed FBXW7 mutations. Fifty-six T-ALL (33.9%) exhibited a wild-type configuration of either gene. Four novel NOTCH1 mutations were identified localized in the C-terminal PEST domain, in the rarely affected LNR repeat domain and in the ankyrin domain. Novel LNR mutations may contribute to a better understanding of the structure of the NOTCH1 negative regulatory region (NRR) and the R1946 mutation in the ankyrin domain may represent an unusual loss-of-function mutation. CONCLUSIONS: Overall, NOTCH1 pathway mutations did not affect the relapse rate and outcome of the extended T-ALL cohort uniformly treated according to CoALL protocols, although NOTCH1 mutations were associated with good response to induction therapy (P = 0.009). Individually, HD and PEST domain mutations might exert distinct functional effects on cellular homeostasis under treatment NOTCH1 pathway activity with prognostic implications.

Pre-prostatic tissue removed in robotic assisted lymph node dissection for prostate cancer contains lymph nodes.

OBJECTIVE: The on-going discussion about extent and best template for pelvic lymph dissection (PLND) motivated us to analyse pre-prostatic tissue (PPT) for lymph nodes and metastases. MATERIALS AND METHODS: From December 2010 to August 2011 PPT was sent for histopathological evaluation during 80 robotic assisted radical prostatectomies (RARP) and one extended staging lymph node dissection. All patients had either a limited (lPLND, n = 44) or an extended lymph node dissection (ePLND, n = 36). Clinical data were retrospectively analyzed and compared to histopathological findings. RESULTS: Lymph nodes were found in PPT in 10/80 (12.5%) patients after RARP and in the one patient after staging ePLND. Mean number of lymph nodes detected in PPT of them was 1.2 (range 1-3). Clinically no differences were found between patients with or without lymph nodes in PPT. In the standard template of either ePLND or lPLND the average number of lymph nodes was 13 (range 2-56). Herein metastases were found in 10 (12.5%) patients after RARP and in the patient after staging ePLND. A metastasis in PPT was only found after staging ePLND. CONCLUSIONS: Pre-prostatic tissue might contain lymph nodes that potentially harbour metastases. In the intention to perform the most accurate staging this tissue should be considered for histopathological evaluation.

Comparison of standardized pre- and postoperative functional pelvic cine-MRI in patients with a bulbourethral composite suspension due to post-prostatectomy incontinence.

OBJECTIVES: To compare functional pelvic cine-MRI in patients with post-prostatectomy incontinence before and after implantation of a bulbourethral composite suspension. PATIENTS AND METHODS: Functional pelvic 1.5 T cine-MRI was performed at rest, under standardized Valsalva pressure and during micturition in six patients with post-prostatectomy incontinence before and 3 months after a bulbourethral composite suspension. Visibility and positioning of the implant as well as membranous urethral length (MUL) and positioning of the bladder neck (BN) in comparison with the pubococcygeal line (PCL) were evaluated. Clinical outcome was measured by patient-reported pad use and standardized questionnaires (ICIQ-UI SF and I-QOL). Paired data were tested with a Wilcoxon signed-ranks test. RESULTS: Surgery was successfully performed in all patients. All patients returned to complete voiding. The ICIQ-UI SF score decreased significantly from median 16.5 to 5 (p = 0.016). I-QOL increased significantly from 70.5 to 93.5 (p = 0.047). Pad use improved from median 2 pads to 0 pads postoperatively (p = 0.031). Four of six patients were completely pad-free, and 2 were failures with persisting urinary incontinence. MRI revealed significant differences of the MUL at rest with median of 8 mm pre- and 13 mm postoperatively (p = 0.016). BN showed a significant elevation with respect to PCL under Valsalva with in median 0.5 to 5 mm postoperatively (p = 0.016). No significant MRI differences were found between patients showing clinical success or failure. CONCLUSIONS: The bulbourethral composite suspension was associated with an increase in urethral length, urethral coaptation zone and bladder neck elevation, implying a non-compressive mode of action.

[Technique of the urethral anastomosis in orthotopic neo-bladder following robot-assisted radical cystectomy (RARC)]. / Technik der urethralen Anastomose bei orthotopem Blasenersatz nach roboterassistierter radikaler Zystektomie (RARC).

The urethral anastomosis in extracorporeally constructed orthotopic neo-bladder following robot-assisted radical cystectomy (RARC) remains a challenge. In principle either pre-posi-tioned single sutures or robotic continuous suture techniques can be applied. In the literature the different techniques are most often not described in detail. In the present work one example for each technique is given and the advantages and disadvantages of both methods are discussed.

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.

[The urethral anastomosis in orthotopic neobladder following robot-assisted radical cystectomy (RARC) at German-speaking centres]. / Urethrale Anastomose bei orthotopem Blasenersatz nach roboterassistierter radikaler Zystektomie (RARC) an deutschsprachigen Robotikzentren.

INTRODUCTION: Following robot-assisted radical cystectomy (RARC) and extracorporeal reconstruction, robotic continuous suture techniques and those using open or robotically pre-positioned single sutures are used for the urethroneovesical anastomosis. METHODS: 62 German-speaking robotic centres were asked in an online questionnaire whether they carried out RARC. Following an affirmative answer further questions were put to the form of the neobladder and the technique of the urethrovesical anastomosis. RESULTS: 80% of the online questionnaires were answered. 44% (n=22) of these centres perform the RARC. According to the answers, given all of the centres but one perform an extracorporeal construction of the neobladder [Studer bladder 73% (n=16), Hautmann bladder 18% (n=4), others 9% (n=2)]. After reconstruction 36% (n=8) of the teams perform a completely open surgical anastomosis with pre-positioned sutures, 24% (n=5) close the anastomosis in a single knot technique using robotically pre-positioned sutures and 40% (n=9) use continuous sutures during the intracorporeal reconstruction or after re-docking the robot. CONCLUSION: According to this questionnaire to German-speaking centres the most common anastomotic technique following extracorporeal reconstruction, mostly a Studer bladder, is that of the pre-positioned single knot sutures. This offers the advantage that a re-docking of the robotic cart is unnecessary. In contrast, however, to robotically performed suturing, there must be enough space in the open procedure to surgically tie-off the sutures of the anastomosis.

Laparoscopic radical cystectomy: initial experience using the single-incision triangulated umbilical surgery (SITUS) technique.

INTRODUCTION: As could be demonstrated for simple and radical nephrectomy, single-incision triangulated umbilical surgery (SITUS) is an interesting alternative to laparoscopic single-site surgery. We present our initial experience with the SITUS technique in radical cystectomy. MATERIALS AND METHODS: Between September 2010 and September 2011, eight patients underwent SITUS radical cystectomy (SITUS Cx), pelvic lymph node dissection and extracorporeal urinary diversion. A cutaneous ureterostomy was performed in three, an ileum conduit in one and an ileal neobladder in four patients. Data were collected prospectively, including patients' characteristics, intraoperative parameters, pathological stage and postoperative outcome. RESULTS: Mean age of the patients was 67 years and the mean body mass index 24 kg/m(2). SITUS Cx was successfully completed in all patients without conversion to conventional laparoscopic or open surgery. Mean surgical time was 434 min and mean estimated blood loss 643 ml. No major intra- or postoperative surgical complications occurred. All patients recovered quickly reporting low postoperative pain levels. Mean hospital stay was 16 (7-24 days). Histopathological evaluation revealed a mean of 16 (6-33) retrieved lymph nodes and no positive margins. CONCLUSION: In the present experience, SITUS Cx proved to be feasible with surgical outcome comparable to conventional techniques. Because SITUS Cx combines the advantages of traditional laparoscopy (straight instruments and triangulation) with those of single-port surgery (superior cosmesis and minimal invasiveness), it presents an attractive alternative to other minimally invasive techniques.

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.