Biomedical subjects
Publications and source records attributed to R Küfer.
High-flow priapism caused by a pathological arterial influx to the cavernous bodies was first described by F.B. Burt in 1960. The pathophysiological differentiation of high- and low-flow priapism was developed in 1983. The development of diagnostic tools for differentiation of different forms of priapism and the progress in the therapy of high-flow priapism from arterial ligation to supraselective embolization is presented.
The WHO classification of renal cell carcinomas (RCC) takes into account chromosomal alterations. New cytogenetic techniques such as comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH) offer alternative methods to the classic cytogenetic banding technique. Clear cell (classic) RCC frequently show the loss of 3p. Papillary RCC are characterized by trisomies and tetrasomies as well as loss of the Y chromosome. CGH analysis demonstrates that DNA copy increase is more common in type I papillary RCC compared to type II. Chromophobe RCC are characterized by losses in chromosomes 1, 2, 6, 10, 13, 17, and 21. Oncocytomas can be divided into cases with rearrangements in the 11q13 region and those with loss of chromosome 1 and the sex chromosomes. Translocations involving chromosome 3, such as t(3;8)(p14;q24.13) and t(2;3)(q35;q21) have been described in familial clear cell RCC. The most recent class of RCC, seen only in men, is referred to as translocation tumors. These tumors demonstrate a tubulopapillary growth pattern and have a t(X;1)(p11.2;q21.2) translocation. Although not required for most clinical diagnoses, CGH and FISH complement the standard histologic diagnosis of RCC and may provide a definitive diagnosis in a small number of challenging cases.
The tissue microarray technique (TMA) represents a powerful diagnostic "high-throughput" tool to analyse DNA/RNA or protein alterations in large patient cohorts in a time and cost effective way. This review focuses on the clinical application of TMA in renal cell carcinoma in modern "translational" medicine--"from bench to bedside". In particular, the advantages of TMA for diagnosis, prognosis and decisions for therapy will be considered in relation to renal cell cancer.
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A 37-year-old man with Klippel-Trénaunay syndrome presented with an episode of painless severe gross hematuria. Magnetic resonance imaging (MRI) revealed vessels of significant diameter in the bladder wall. Diagnostic imaging is mandatory in order to be aware of the extent of the lesion as the bleeding identified intraoperatively may only be the "tip of the iceberg." If conservative means fail, laser coagulation should be the treatment of choice.
BACKGROUND: Family history is one of the strongest risk factors for prostate cancer. In this prospective study we evaluated the results of prostate cancer screening performed in healthy brothers of prostate cancer patients. The detection rate of prostate cancer and the positive predictive value of the examinations were determined. MATERIAL AND METHODS: The study population comprised 513 healthy men who were 38-75 years of age (median 62.0 years). Of these men, 268 having only one affected brother with prostate cancer were assigned to the sporadic group, and 245 probands having 2-10 affected relatives were assigned to the familial group. An abnormal PSA and/or a pathological digital rectal examination (DRE) was noted in 17.5% of familial (43/245) and 15.8% of sporadic probands (35/268). A biopsy of the prostate was performed in 60.5% of familial (26/43) and 71.4% of sporadic (25/35) men with pathological findings. RESULTS: Prostate cancer was found in 15 of 26 familial (57.7%) and 16 of 25 sporadic (64.0%) probands by prostate biopsy. The overall detection rate was 6.0% (31/513). CONCLUSION: Due to an increased prevalence the detection rate of prostate cancer and the positive predictive value of PSA and/or DRE are higher in men with a family history as expected in an unselected population. Our data suggest that in predisposed men prostate cancer screening should be recommended early. Furthermore an early indication for prostate biopsy is necessary. This recommendation should also be applied if only one first-degree relative has prostate cancer.
PURPOSE: Neobladder reconstruction is considered the best option for patients requiring cystectomy. Limited information is available about incidence, etiology and therapeutic options for neobladder emptying failure in males. MATERIALS AND METHODS: In a retrospective study we analyzed the data of a consecutive series of 655 male patients (age range 23 to 82 years, median 63; followup range 0 to 208 months, median 36.5) who received an ileal neobladder following radical cystectomy at our institution. All patients had a complete followup until death or until December 2003. Data on all diagnostic and therapeutic procedures performed for neobladder emptying failure were collected. RESULTS: Of 655 patients 75 (11.5%) had at least 1 episode of failure emptying the neobladder requiring some form of therapy during followup. Failure was due to dysfunctional voiding in 23 patients (3.5%) and mechanical obstruction in 52 patients (8%). Causes of mechanical obstruction were benign strictures of the neovesicourethral anastomosis (23 patients, 3.5%) or the anterior urethra (11 patients, 1.7%), neoplastic obstruction by local tumor recurrence (13 patients, 2.0%) or a nonurological malignancy (1 patient, 0.2%), and obstruction by mucosal valves (3 patients, 0.5%) or a foreign body (1 patient, 0.2%). In 38 of 52 patients with mechanical obstruction of the neobladder outlet emptying was fully restored with endourological procedures, while in 14 of 52 patients long-term catheterization was necessary. Catheterization was the therapy of choice for all patients with dysfunctional voiding. CONCLUSIONS: Neobladder emptying failure is of major concern but is not an argument against orthotopic diversion. The overall rate of transient or permanent neobladder emptying failure in males is high but most of the mechanical causes can be managed endoscopically, while the rate of patients with long-term catheterization for dysfunctional voiding is relatively low.
Little is known about the motives of German men to attend or refuse preventive checkups for prostate cancer. The aims of this study were to investigate if in men with familial predisposition screening behaviours are influenced by epidemiological or clinical parameters of prostate cancer of their affected relatives. 476 probands with one and 312 probands with at least two affected relatives were advised in writing to have a PSA-test and DRE done at their local urologists. We evaluated if the response rate was correlated to the proband's age, to the number and the age of onset of their affected relatives and also to the clinical course of their disease. Our data implicate that in men with familial predisposition the acceptance of prostate cancer screening is influenced only by individual characteristics and personal attitude and not by factors within the family. To which extent the awareness of disease risk is modified by familial predisposition remains to be evaluated.
Prostate cancer is the most common malignancy in males. Men aged 50 years and older are recommended to undergo an annual digital rectal examination (DRE) and determination of prostate-specific antigen (PSA) in serum for early detection. Fortunately, disease-specific mortality continues to decline as a result of advances in screening, staging, and patient awareness. However, about 30% of men with a clinically organ-confined disease show evidence of extracapsular extension or seminal vesicle invasion on pathological analysis. Consequently, there is a need for more accurate diagnostic tools for planning tailored treatment. A variety of modern imaging techniques has been implemented in an attempt to obtain more precise staging, thereby allowing for more detailed counseling, and instituting optimum therapy. This review highlights developments in prostate cancer imaging that may improve staging and treatment planning for prostate cancer patients.
Data emerging from DNA microarray experiments are usually difficult to interpret. While the level of expression of several thousand genes can be measured in a single experiment, only a few dozen experiments are normally carried out, leading to data sets of very high dimensionality and low cardinality. The computational analysis of gene expression data makes significant usage of machine learning and statistical methods. Nevertheless, caution should be used in the blind adoption of these methods, as this usually leads to an over-interpretation of the expression profiles. The following presentation provides an overview of up-to-date principles of biostatistical analysis. A potential application for the analysis of high-dimensional expression profiles of prostate cancer is given.
PURPOSE: Chorioallantoic membranes have been used as a reliable biomedical assay system for many years. Chicken eggs in the early phase of breeding are between in vitro and in vivo systems but may provide an immunodeficient, vascularized test environment. We tested this model as an in vivo system for prostate cancer research. MATERIALS AND METHODS: Single cell suspensions of LNCaP, PC-3 and Tsu-Pr1 human prostatic cancer cell lines as well as 2 immortalized normal human prostate epithelial cell lines were inoculated on the chorioallantoic membrane of fertilized chicken eggs on day 5 or 6 of breeding. Tumor growth and viability of the embryo was evaluated by stereo microscopy. At day 10 the membranes were removed and embedded in paraffin. Cell morphology was assessed after hematoxylin and eosin staining. Cellular expression of cytokeratin, prostate specific antigen and androgen receptor as well as apoptosis induction was confirmed by immunohistochemistry. RESULTS: Three days after tumor cell inoculation on the extraembryonic vascular system of the chorioallantoic membrane cell growth and formation of 3-dimensional tumors became apparent in 100% of inoculated membranes. Strong neo-angiogenesis was detected next to the established tumors and tumor cells invading the stroma of the chorioallantoic membrane. Cytokeratin expression as well as prostate specific antigen and androgen receptor in LNCaP cells confirmed the human prostate tumor origin. Assessment of quantitative in vivo apoptosis induction in LNCaP cells after intravenous injection of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate confirmed the model as a versatile in vivo system. CONCLUSIONS: The well vascularized chorioallantoic membrane of bred chicken eggs is a suitable system for early in vivo cancer research. Reliable growth of prostate cancer cell lines is feasible and allows the evaluation of proliferation and apoptosis induction after intravascular or topic application of anticancer drugs. Exploitation of this assay enables a substantial reduction in or substitution for subsequent animal experiments.
AIM: Standard diagnostic tools for vesico-intestinal fistulas are cystoscopy, cystography, colonoscopy, and contrast enema. The aim of our study was to evaluate the efficacy of transrectal 3D-ultrasound with contrast media in these patients. METHOD: From 5/98 to 12/99 we examined 10 patients with symptoms of a vesico-intestinal fistula (pneumaturia, faecaluria). After placement of a transurethral catheter a transabdominal ultrasound examination (Kretz Combison 530) was performed with the bladder half full to evaluate the bladder wall. Then the bladder was filled with diluted ultrasound contrast media (Levovist 40 mg/ml) to visualize the flow from the bladder towards the fistula. To verify a flow through the bladder wall a colour Doppler sonography of the region of interest was added. To evaluate form and extent of the fistula a transrectal ultrasound with 3D-image assessment was performed. RESULTS: Using this technique it was possible to demonstrate a vesico-intestinal fistula in 9 of 10 patients. In all cases these findings were confirmed by the standard diagnostic procedures. The fistulas were caused by: bladder carcinoma (n = 1), carcinoma of the colon (n = 2), Crohn's disease (n = 3) and diverticulitis of the sigma (n = 3). One patient presented with a neovesico-intestinal fistula in an irradiated local recurrence of bladder carcinoma. In one patient with Crohn's disease whose only symptom was pneumaturia all diagnostic tools failed to provide the diagnosis. CONCLUSION: For the first time vesico-intestinal fistulas could be demonstrated by ultrasound with 3D-image assessment using contrast media. This technique might be an effective addition to the standard diagnostics of vesico-intestinal fistulas reducing the exposure to radiation.
PURPOSE: The influence of shockwaves applied during extracorporeal shockwave lithotripsy on the function of implantable cardioverter defibrillators was evaluated. Mechanical influences as well as proper electrical function were tested in an experimental approach. MATERIALS AND METHODS: Two implantable defibrillators (Ventak Mini 1743 and AVII 1821) were exposed to the shockwaves of a new-generation lithotripter. Each of the antidysrhythmic devices was tested at several distances from and within the focus of the lithotripter. All studies were performed with maximum energy and the number of shockwaves used for stone treatment. The devices were connected to an ECG simulator, and continuous recording of a surface ECG, a shock ECG, and marker channel was performed. RESULTS: No macroscopic and microscopic mechanical damage was observed. The detection function of the implantable defibrillators was not altered by any electromagnetic artifacts even when brought into the focus of the shockwaves. All induced ventricular dysrhythmias were terminated properly regarding artifact sensing. However, after defibrillation, the pacing function of the Ventak Mini cardioverter defibrillator, which was programmed into the demand mode, failed. In this case, there was no post-shock pacing in the period of post-defibrillation asystole. The failure was caused by artifact oversensing. CONCLUSION: In patients with implanted cardiac devices undergoing treatment with a new-generation lithotripter, deactivation of the defibrillator is not mandatory. For safety reasons, continuous ECG recording is recommended. To avoid pacing failure by artifact oversensing, the shockwaves should be applied in a R-wave synchronous mode.
OBJECTIVES: To evaluate the clinical results after one year's experience with a new generation lithotriptor, the Dornier Compact Delta. MATERIAL AND METHODS: The authors treated 278 patients between the ages of 7 and 88 years, presenting with ureteral stones in 49% of cases. The mean stone diameter was 10.5 (range: 3 to 50 mm). The Compact Delta is equipped with a fixed or induced frequency electromagnetic shock wave generator. Stones are visualized by digital fluoroscopy and/or ultrasound scanning. Therapeutic centering is performed by isocentric displacement of the patient. Corrections can be easily made during treatment. An average of 3,202 (range: 500-5,800) shock waves were applied with a mean energy level of 4.5 (range: 1-6). Treatment was performed without premedication. RESULTS: A feeling of discomfort or even pain was reported in 75% of cases and treated with intravenous analgesic. Ninety-five per cent of patients were discharged with no residual stones or with residual fragments in the process of spontaneous evacuation. This result was obtained with one treatment session in 66% of cases and two sessions in 25% of cases. Five per cent of patients required a postoperative complementary manipulation. CONCLUSION: The combination of digital fluoroscopic and ultrasound stone detection ensures rapid and reliable localization. The Compact Delta is efficient and does not induce any complications. The preliminary results with this new mobile system show an equivalent efficacy to that of the fixed system with greater flexibility and improved comfort of use.