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The Journal of Urology | 1996

Prognostic Value of Urokinase Plasminogen Activator and Plasminogen Activator Inhibitor-1 in Renal Cell Cancer

R. Hofmann; Antonie Lehmer; R. Hartung; Cordula Robrecth; Markus Buresch; Franziska Grothe

PURPOSEnUrokinase type plasminogen activator and its inhibitor plasminogen activator inhibitor are associated with invasion and formation of metastases in tumors. In a prospective study urokinase and plasminogen activator inhibitor-1 content in renal cell cancer and benign renal tissue was correlated with the traditional factors of TNM staging and grading as well as ploidy and actual clinical outcome of the patients.nnnMATERIAL AND METHODSnA total of 152 patients, who underwent transperitoneal tumor nephrectomy for renal cell cancer, was followed for a mean of 23.9 months. Urokinase and plasminogen activator inhibitor-1 from the tumor tissue and corresponding benign renal tissue were quantified from detergent extracted tissue samples (1% triton-X = 100 in TBS) and measured with an enzyme-linked immunosorbent assay.nnnRESULTSnUrokinase content correlated with the development of distant metastases (log rank 4.32, p = 0.037). Cutoff value was 0.84 ng/mg. A group of 11 patients were considered to be at high risk for metastases (9 events) based on urokinase greater than 0.84 ng/mg., while 94 patients were considered to be at low risk (5 events) with urokinase less than 0.84 ng/mg. Plasminogen activator inhibitor-1 significantly correlated with the prevalence of distant metastases (log rank 5.17, MO, 10.04 versus M1, 23.79, p = 0.02) and the development of new metastases postoperatively (MO, 10.85 versus M1, 27.36, p = 0.001). Cutoff value was 12 ng/mg. protein. A group of 41 patients were considered at high risk for relapse (6) based on plasminogen activator inhibitor-1 greater than 12 ng/mg. protein compared to 55 patients with plasminogen activator inhibitor-1 less than 12 ng/mg. protein with only 1 relapse during followup.nnnCONCLUSIONSnPlasminogen activator inhibitor-1, the specific inhibitor of urokinase is a strong and independent prognostic factor in predicting early relapse of renal cell carcinoma. High and low risk groups for disease-free survival can be discriminated by plasminogen activator inhibitor-1 antigen content in the tumor tissue.


The Journal of Urology | 1991

Purulent corporeal cavernositis secondary to papaverine-induced priapism

J. Ullrich Schwarzer; R. Hofmann

Intracavernous autoinjection of vasoactive substances is used to treat erectile dysfunction. Infection of the corpora cavernosa can be a serious life-threatening complication with this treatment modality. Cavernositis is an unusual complication, especially in otherwise healthy men. In diabetic patients with altered blood supply to the penis and a change of cavernous tissue ischemia can lead to a fulminant infection. We report on a 63-year-old diabetic patient who presented with purulent cavernositis a few weeks after beginning intracavernous injection of papaverine. Treatment included bilateral corporotomy, debridement, and placement of intracorporeal irrigation and suction drains. The patient survived this serious infection leaving both corpora cavernosa with severe fibrosis.


World Journal of Urology | 1997

Iridium 192 high-dose-rate brachytherapy —a useful alternative therapy for localized prostate cancer?

R. Paul; R. Hofmann; J. U. Schwarzer; R. Stepan; H. J. Feldmann; P. Kneschaurek; M. Molls; R. Hartung

We report on a novel protocol involving iridium 192 high-dose-rate brachytherapy and follow-up of up to 130 months in patients with prostatic carcinoma. Using regional anesthesia, five to seven hollow needles are placed within the prostate by perineal puncture under ultrasound guidance. A 9-Gy prostate dose is applied followed by 30 min of hyperthermia (since 1991). This treatment is repeated once after 7 days; 2 weeks later, 18 × 2-Gy external beam radiation (small-field prostate) is added as percutaneous dose saturation. Since 1984 we have treated 40 patients with this protocol. Local tumor control was achieved by means of prostatic biopsy at 18 months after therapy and determination of prostate-specific antigen (PSA) values in bout 70% of the patients; after a mean follow-up period of more than 6 years (16–130 months), 80% of the patients show either no evidence of disease or stable disease. We therefore conclude that iridium 192 high-dose-rate brachytherapy is a useful alternative in the treatment of localized prostate cancer in patients who are not eligible for radical prostatectomy.


Urological Research | 1990

Laser-induced shock wave lithotripsy

R. Hofmann; R. Hartung; Heinz Schmidt-Kloiber; Erich Reichel

SummaryWith a high intensity Q-switched Nd-YAG laser shock waves can be generated in a liquid close to the calculus. Up to 80 mJ single pulse energy with 8 nsec pulse duration can be transmitted through flexible quartz fibers. Energy conversion and enhancement can be accomplished at the fiber tip with optical focussing of the light at the quartz tip, with irrigation solutions and with high pulse energies. Iron-III-dextran solutions (1 mg Fe3+/1) and magnesium chloride (50 mmol/l) increased the pressure in the laser induced breakdown up to ten times (8,000–10,000 bar). Smaller stone particles and higher efficacy in stone fragmentation could be achieved.


World Journal of Urology | 1989

Ureteral stents — materials and new forms

R. Hofmann; R. Hartung

SummaryThree different types of polymers are currently used for self-retained ureteral stents: thermoplastic materials such as polyurethanes, and thermoset elastomers such as silicone and hydrogels. Polyurethane stents are easy to form and have high drainage capacity, whereas silicone shows the best biocompatibility but a lower drainage efficacy than the former. A mock urinary system consisting of a “collecting system” and a 9-F tube was used to evaluate the flow characteristics of various double-pigtail stents in cases of urinary obstruction. For simulation of an unobstructed urinary system a human urogenital system was used. “Inner flow” polyurethane stents showed the best drainage as compared with “inner flow” silicone and “outer flow” ESWL stents in an obstructed ureter, whereas ESWL stents maintained the best flow in an unobstructed ureter or in respect to conventional stents with obstructed sideports.


Urological Research | 1986

Activity of phagocytic granulocytes in patients with prostatic cancer.

R. Hofmann; Antonie Lehmer; J. Braun; S. Bauer

SummaryChemilumenescence (CL) occurs due to the phagocytosis of bacteria and of tumor cells by polymorphonuclear neutrophils (PMN). Levels of CL were measured in patients with prostatic cancer and from normal subjects. Patients with advanced disease (stage C, D) showed no elevated CL levels as compared to healthy individuals or patients with minimal disease (stage A, B). Following external radiation therapy in patients with stage A-C prostatic carcinoma high levels of CL were recorded. Estrogen medication also resulted in increased CL levels, while estramustine did not affect phagocytic activity. Intradermal BCG vaccination caused increased PMN activity. Progressive prostatic cancer in hormone treated patients was associated with increased CL as compared to patients with stable or regressive disease.


Urologia Internationalis | 1987

Morphologische Untersuchungen des Urothels nach Einwirkung intensiver Nanosekunden-Laserpulse

R. Hofmann; R. Hartung; K. Geissdörfer; R. Ascherl; W. Erhardt; Heinz Schmidt-Kloiber; Erich Reichel; H. Schöffmann

The energy of a Nd-YAG laser (1,064 nm wave length, 8 ns pulse duration) was used to irradiate the urothelium of the ureter or bladder and kidney parenchyma in pigs. Single pulse energy was 50-120 mJ with a 20-Hz repetition rate. The horizontal laser beam was reflected 90 degrees down by a 100% mirror and with a specially designed apparatus focussed on the surface of the tissue. Laser light from a quartz glass fiber was also focussed directly onto the tissue. Urothelium and kidney parenchyma were irradiated in 7 pigs. Tissue samples were examined histologically and raster electron microscopically 2, 4, 8 and 12 days after irradiation. No macroscopic lesion could be found. Maximum energy caused a small cone of 40 micron depth. No thermic effects or necrosis resulted, so that no harm is to be expected with unintentional irradiation.


Urologia Internationalis | 1984

Natural Killer Cell Activity in Patients with Prostatic Carcinoma and Its in vivo Boosting with Bacillus Calmette-Guérin

B. Schwemmer; Antonie Lehmer; R. Hofmann; J. Braun

In patients with prostatic carcinoma, natural killer (NK) cell activity was monitored in a chromium release assay. Cells from the human myeloid cell line K 562 and from a human prostatic cancer cell line (PC 3) were used as target cells. Additionally, in vitro stimulation with beta-interferon was done in each sample. NK activity in patients with localized prostatic cancer was increased as compared to age-matched controls. Patients with advanced disease showed reduced levels of NK activity. Furthermore, hormonally treated patients in relapse had significantly lower activity than patients in remission or with stable disease. Hormone therapy was without major influence on NK activity. BCG vaccination as an adjuvant immunotherapy was done in a small group of patients. Baseline NK activity and interferon-stimulated activity were enhanced by BCG in most cases.


Urologia Internationalis | 1992

Adenosine Triphosphate and Adenosine Diphosphate in Human Semen: Correlation with Sperm Count and Motility

R. Hofmann; Antonie Lehmer; Edeltraud Gürster; R. Hartung

Adenosine triphosphate (ATP) and adenosine diphosphate (ADP) have been correlated with traditional semen parameters such as forward motility and sperm count. ATP and ADP were determined by a bioluminescence assay using the luciferin-luciferase reaction. Short boiling of the ejaculate was performed to inactivate phosphatases (ATPases) in the seminal plasma and the sperm tails. Fresh and deep-frozen semen samples from 45 men with oligozoospermia (n = 22) and normal sperm count (n = 23) were evaluated. Freezing of the sperm for 12 weeks did not effect the ATP or ADP content in the spermatozoa as compared to fresh semen. ATP and ADP concentration was in the range of picomoles/microliter and showed a significant correlation with the number of normal sperm per milliliter and a less marked correlation with the sperm motility. ATP and ADP concentration in the spermatozoa can be measured relatively easy and is reproducible. Unlike the monotonous evaluation of sperm motility by a technician, this biochemical method provides an objective parameter for semen quality. These qualities suggest that this method could be a way to determine the fertilizing potential of semen and to relate this to actual pregnancy rates.


Archive | 1988

Laser-Induced Shock Wave Lithotripsy (LISL)-Biologic Effects and First Clinical Application

R. Hofmann; R. Hartung; H. Schmidt-Kloiber; E. Reichel

Continuous wave lasers induce thermic lesions in an irradiated tissue by transformation of the laser energy into heat.Laser energy from a pulsed Nd-YAG laser with a pulse duration in the nanosec. range is changed into mechanic energy as Shockwaves by creation of a localized plasma.This procedure-laser induced breakdown-can be used for disintegration of concrements(e.g.urinary calculi)(1).

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