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H J Leisinger

Publications and source records attributed to H J Leisinger.

At least 19 recordsLinked to original sources
PubMed1998

Persistence of parvovirus B19 DNA in testis of patients with testicular germ cell tumours.

Germ cell tumours (GCT) of the testis are the most common malignant tumours occurring in young adults. In view of the young age of patients, the increasing incidence of GCT and the overexpression of wild-type p53 observed in a majority of tumours, the possibility of the involvement of a virus in the development of this cancer was considered. Testicular GCT were analysed for the presence of cytomegalovirus and Epstein-Barr virus (EBV), which are known to cause overexpression of wild-type p53 protein, and parvovirus B19. The testicular tissue of 39 patients with testicular GCT and 12 patients with healthy testicular tissues was tested for presence of viral DNA by PCR. Neither cytomegalovirus nor EBV DNAs were detected in the 39 tumours analysed, but parvovirus B19 DNA sequences were demonstrated in the testicular tissue of 85% (33/39 cases) of patients with GCT. The sera of 16 of the 39 patients with GCT were tested for the presence of parvovirus B19 IgM and IgG. B19-specific IgG was detected in the sera of 11 patients (69%). Only one case was positive for parvovirus B19 IgM, which was also shown to have B19 genome sequences in the serum by PCR, indicating that in a majority of cases an acute B19 infection can be excluded as being the source of the B19 DNA sequences in the testis. B19 DNA could not be detected in normal testicular tissue and thus parvovirus B19 could play a role, direct or indirect, in the development of testicular GCT or have tropism for the tumour cells.

Adolescent↗
PubMed1997

[First evaluation of a year of ambulatory surgery in urology].

Day surgery in urology is in full growth actually. The present report is based on our first 120 patients. Low post-operative complication rate, patients' satisfaction and economical savings are the main factors for the important increase in this type of surgery.

Ambulatory Surgical Procedures↗
PubMed1997

Clinical evaluation of a method for detecting superficial surgical transitional cell carcinoma of the bladder by light-induced fluorescence of protoporphyrin IX following the topical application of 5-aminolevulinic acid: preliminary results.

BACKGROUND AND OBJECTIVE: In bladder cancer, conventional white light endoscopic examination of the bladder does not provide adequate information about the presence of "flat" urothelial lesions such as carcinoma in situ. In the present investigation, we examine a new technique for the photodetection of such lesions by the imaging of protoporphyrin IX (PpIX) fluorescence following topical application of 5-aminolevulinic acid (ALA). STUDY DESIGN/MATERIALS AND METHODS: Several hours after bladder instillation of an aqueous solution of ALA in 34 patients, a Krypton ion laser or a filtered Xenon arc-lamp was used to excite PpIX fluorescence. Tissue samples for histological analysis were taken while observing the bladder wall either by means of a video camera, or by direct endoscopic observation. RESULTS: A good correlation was found between the PpIX fluorescence and the histopathological diagnosis. On a total of 215 biopsies, 143 in fluorescent and 72 in nonfluorescent areas, all visible tumors on white light cytoscopy appeared in a bright red fluorescence with the photodetection technique. In addition, this method permitted to discover 47 unsuspected carcinomatous lesions on white light observation, among which 40% were carcinoma in situ. CONCLUSION: PpIX fluorescence induced by instillation into the bladder of 5-ALA is an efficient method of mapping the mucosa in bladder carcinoma.

Administration, Cutaneous↗
PubMed1997

Clinical assessment of fluorescence cytoscopy during transurethral bladder resection in superficial bladder cancer.

The prognosis of superficial bladder cancer in terms of recurrence and disease progression is related to bladder tumor multiplicity and the presence of concomitant "plane" tumors such as high-grade dysplasia and carcinoma in situ. This study in 33 patients aimed to demonstrate the role of fluorescence cystoscopy in transurethral resection of superficial bladder cancer. The method is based on the detection of protoporphyrin-IX-induced fluorescence in urothelial cancer cells by topical administration of 5-aminolevulinic acid. The sensitivity and the specificity of this procedure on apparently normal mucosa in superficial bladder cancer are estimated to be 82.9% and 81.3%, respectively. Thus, fluorescence cytoscopy is a simple and reliable method for mapping the bladder mucosa, especially in the case of multifocal bladder disease, and it facilitates the screening of occult dysplasia.

Adult↗
PubMed1997

[Vaporization of urethral stenosis using the KTP 532 laser].

The authors treated 16 patients presenting with a total of 20 anterior urethral strictures using the KTP 16 Laser. The aetiology was iatrogenic in 50% of cases, infectious in 20% of cases, traumatic in 20% of cases and unknown in 10% of cases. The stricture was situated in the bulbous urethra (80%), membranous urethra (10%) or penil urethra (10%). Laser vaporization of the urethral stricture was performed over the entire circumference of the urethra when necessary, followed by bladder drainage by urethral catheter for 24 hours. All patients were prospectively reviewed at 3 weeks, 3 months and 6 months (clinical symptoms, uroflowmetry, cystourethrography). A complete symptom and urodynamic success was obtained in 13 patients (81%) at 3 and 6 months. The stricture recurred in 4 patients, but only three of them (19%) required treatment (reoperation of repeat dilatations). The mean maximum flow rate increased from 6 mL/s to 20 mL/s at 3 months and was maintained at 19 mL/s at 6 months. No intraoperative or postoperative complications were observed. In conclusion, our results confirm that KTP 532 laser urethral strictures is a reliable and effective method in the medium term. These good results also suggest an advantage in terms of the recurrence rate in comparison with internal urethrotomy. However, our series needs to be evaluated with a longer follow-up and prospective, randomized trials comparing the two methods need to be conducted.

Adult↗
PubMed1997

[The clinical value of fluorescence cystoscopy in the detection of superficial transitional epithelial cell carcinoma of the bladder].

The prognosis of superficial bladder cancer in terms of local recurrence and transformation into invasive cancer is related to the multiplicity of tumor sites and the concomitant presence of "flat" tumours, such as dysplasia and carcinoma in situ. This study of 51 patients emphasizes the value of fluorescence cystoscopy in the early detection of superficial transitional cell carcinomas. This method is based on induction of fluorescence in carcinomatous sites which selectively accumulate an endogenous photosensitizer, protoporphyrin IX, in response to intravesical administration of its precursor, 5-aminolevulinic acid. The sensitivity of the method in the present series was close to 93%. Fluorescence cystoscopy is a simple and reliable method to map the bladder mucosa looking for areas of dysplasia and carcinoma in situ.

Administration, Intravesical↗
PubMed1997

[Renal oncocytoma: nephrectomy or tumorectomy? Description of five cases and review of the literature].

Oncocytoma is an uncommon benign tumor of the kidney. Its incidence represents 3 to 10% of all solid renal masses. This diagnosis, seldom recognized before the operation, is often revealed by anatomo-histological examination. Surgical treatment of a small tumor, ever the most benign, can be limited to enucleation or partial nephrectomy to spare renal parenchyma. When a small, solid and well-confined renal mass is discovered, the diagnosis of oncocytoma must be considered and the usual investigations (abdominal ultrasound, CT-scan...) must be completed by renal angiography to obtain as much information as possible in support of the diagnosis of oncocytoma, justifying nephron-sparing surgery.

Adenoma, Oxyphilic↗
PubMed1997

Frequent p16INK4 (MTS1) gene inactivation in testicular germ cell tumors.

The molecular mechanisms responsible for the development of testicular germ cell tumors (GCTs) have not as yet been elucidated. The aim of the present study was to determine whether genetic alterations of p16INK4 (MTS1) and/or cyclin-dependent kinase 4 (CDK4) occur in the genesis of these tumors. We have analyzed these two genes in 29 testicular GCTs, seminomas, and nonseminomas. None of the tumors showed either p16INK4 or CDK4 mutations. Only 1 of the 29 GCTs displayed loss of heterozygosity of the p16INK4 gene. No homozygous deletions of p16INK4 were detected. Evidence of hypermethylation of p16INK4 exon 1, however, was demonstrated in 13 of the 26 (50%) GCTs analyzed. Tumor samples having exon 1 of p16INK4 methylated expressed significantly lower levels of p16INK4 mRNA, as analyzed by reverse transcriptase polymerase chain reaction. These results suggest that p16INK4 inactivation plays a role in the genesis of GCTs.

Adolescent↗
PubMed1996

Germ cell tumors of the testis overexpress wild-type p53.

Several recent studies have suggested that testicular germ cell tumors express high levels of wild-type p53 protein. To clarify and confirm this unexpected result, we have investigated seminomatous and nonseminomatous germ cell tumors at the genomic, mRNA, and protein levels. Thirty-five tumors were examined for p53 overexpression using antibodies directed against the p53 (PAb1801, PAb240, and CM1), mdm2 (IF2), and p21Waf1/Clp1 (EA10) proteins. Thirty-two tumors were screened for p53 mutations by single-strand conformation polymorphism analysis. Eighteen tumors were screened with a functional assay that tests the transcriptional competence of human p53 protein expressed in yeast. On frozen sections, 100, 65, 35, 73, and 0% of tumors reacted with the CM1, PAb240, PAb1801, IF2, and EA10 antibodies, respectively. No p53 mutations were detected by single-strand conformation polymorphism or by functional assay. The fact that many tumors overexpress wild-type p53 but not mdm2 rules out mdm2 overexpression as a general explanation for the presence of wild-type p53 in these tumors. The absence of p21 overexpression suggests that p53 may be unable to activate transcription of critical target genes, which may explain why the presence of wild-type p53 is tolerated in this tumor type, although the mechanism for this transcriptional inactivity remains to be established.

Cyclin-Dependent Kinase Inhibitor p21↗
PubMed1995

[Possibilities of surgical therapy in prostatic carcinoma].

Radical surgical treatment of localized prostate cancer is performed to heal the patient of his malignant disease. Surgery for advanced prostate cancer, e.g. transurethral resection for obstruction or hemorrhage, is always a palliative modality and has to be seen in the context of systemic treatment. Radical prostatectomy is a major intervention which allows complete removal of the prostate gland and the seminal vesicles at the same time. Due to resection at the distal end of the prostatic urethra, the bladder sphincter system is partially destroyed. In general, to guarantee radicality, the erectile nerves and vessels are sectioned, resulting in erectile impotency. Preservation of these structures to maintain potency is indicated only exceptionally. Radical prostatectomy is today a routine operation with minimal mortality (0.5-1%) and minor complication rate. Average hospitalization is about 10 days. Long-term postoperative morbidity is characterized by urinary incontinence and erectile impotency. Incontinence takes a long time to heal. A certain number of patients will keep a generally not very bothersome stress dribbling; however, some may show complete leakage, necessitating an anti-incontinence operation. For an indication of radical prostatectomy, two essential factors have to be considered: the usually extremely slow growth of prostate cancer and the high prevalence of clinically insignificant latent carcinomas. It is for these reasons and for the consequences on live quality that radical prostatectomy should not be performed on patients with a life expectancy of less than 10 years.

Aged↗