John Provet

Anastomotic Strictures Following Radical Prostatectomy: Risk Factors and Management

Stricture of the anastomosis between the bladder neck and membranous urethra after radical prostatectomy can cause significant voiding dysfunction. Of 156 patients undergoing radical prostatectomy for localized prostatic carcinoma 18 had anastomotic stricture for an over-all incidence of 11.5%. The risk factors for anastomotic stricture and the treatment outcome in these patients were analyzed. Excessive intraoperative blood loss, extravasation of urine at the anastomotic site and a prior transurethral prostatic operation significantly contributed to the development of stricture. More than half of the patients did not respond to simple dilation alone. Cold knife incision of the stricture by itself was effective in only 62% of the patients. The remaining patients required periodic dilation to maintain an adequate urine flow. Incision of the stricture with electrocautery resulted in urinary incontinence in all patients.

Partial Nephrectomy for Renal Cell Carcinoma: Indications, Results and Implications

Of 52 patients who underwent partial nephrectomy for tumor 44 were found to have renal cell carcinoma. The indications for this parenchyma-sparing procedure were categorized according to the initial status of the contralateral kidney and included bilateral tumors or tumor in a solitary kidney in 16 patients (mandatory indications), unilateral carcinoma with compromise of the contralateral kidney by a benign disease process in 9 (relative indications) and small peripheral tumor with a normal contralateral kidney in 19 (elective indications). There were 4 recurrences that accounted for 3 deaths, all in patients with mandatory indications. All patients who underwent partial nephrectomy for relative or elective indications were without definite evidence of recurrent disease at last followup (over-all mean 36 months). Our results suggest that conservative surgery can often provide effective and advantageous therapy for renal cancer and we encourage further consideration of the role of partial nephrectomy as an alternative to radical nephrectomy in selected patients with small peripheral tumors and normal contralateral kidneys.

FORMATION OF ASYMMETRIC UNIT MEMBRANE DURING UROTHELIAL DIFFERENTIATION

Mammalian urothelium undergoes unique membrane specialization during terminal differentiation making numerous rigid-looking membrane plaques (0.3–0.5 μm diameter) that cover the apical cell surface. The outer leaflet of these membrane plaques is almost twice as thick as the inner leaflet hence the name asymmetric unit membrane (AUM). Ultrastructural studies established that the outer leaflet of AUM is composed of 16 nm particles forming two dimensional crystals, and that each particle forms a ‘twisted ribbon’ structure. We showed recently that highly purified bovine AUMs contain four major integral membrane proteins: uroplakins Ia (27 kD), Ib (28 kD), II (15 kD) and III (47 kD). Studies of the protease sensitivity of the different subdomains of uroplakins and other considerations suggest that UPIa and UPIb have 4 transmembrane domains, while UPII and UPIII have only one transmembrane domain. Chemical Crosslinking studies showed that UPIa and UPIb, which share 39% amino acid sequence, are topologically adjacent to UPII and UPIII, respectively, thus raising the possibility that there exist two biochemically distinct AUM particles, i.e., those containing UPIa/UPII vs. UPIb/UPIII. Bovine urothelial cells grown in the presence of 3T3 feeder cells undergo clonal growth forming stratified colonies capable of synthesizing and processing all known uroplakins. Transgenic mouse studies showed that a 3.6 kb 5′-flanking sequence of mouse uroplakin II gene can drive the expression of bacterial LacZ gene to express in the urothelium. Further studies on the biosynthesis, assembly and targeting of uroplakins will offer unique opportunities for better understanding the structure and function of AUM as well as the biology of mammalian urothelium.

Radical prostatectomy for stage D1 prostate cancer: Prognostic variables and results of treatment

Surgical extirpation of the primary tumor together with the involved regional nodes has been considered ineffective treatment for locally disseminated prostatic carcinoma. We retrospectively reviewed our experience with 42 patients with Stage D1 disease who underwent radical prostatectomy and bilateral pelvic lymphadenectomy and who had a follow-up of one to thirteen years (mean 5 years). The following variables affecting survival and tumor progression were analyzed: (1) tumor grade and local extent; (2) number of positive lymph nodes, and (3) adjuvant therapy. The overall five- and ten-year survival was 79.5 per cent and 28 per cent compared with the expected survival of an age-matched control group of 88 per cent and 28 per cent, respectively. The degree of tumor differentiation had no effect on prognosis, but local tumor bulk and the number of involved lymph nodes significantly changed the disease progression and survival rate. Patients with low local tumor bulk and one positive node survived as long as the age-matched male population group. Our data suggest that radical prostatectomy may represent a valuable treatment in selected patients with Stage D1 prostate carcinoma.

Radical prostatectomy for stage D1 prostate cancer

Abstract Surgical extirpation of the primary tumor together with the involved regional nodes has been considered ineffective treatment for locally disseminated prostatic carcinoma. We retrospectively reviewed our experience with 42 patients with Stage D1 disease who underwent radical prostatectomy and bilateral pelvic lymphadenectomy and who had a follow-up of one to thirteen years (mean 5 years). The following variables affecting survival and tumor progression were analyzed: (1) tumor grade and local extent; (2) number of positive lymph nodes, and (3) adjuvant therapy. The overall five- and ten-year survival was 79.5 per cent and 28 per cent compared with the expected survival of an age-matched control group of 88 per cent and 68 per cent, respectively. The degree of tumor differentiation had no effect on prognosis, but local tumor bulk and the number of involved lymph nodes significantly changed the disease progression and survival rate. Patients with low local tumor bulk and one positive node survived as long as the age-matched male population group. Our data suggest that radical prostatectomy may represent a valuable treatment in selected patients with Stage DI prostate carcinoma.

Prostatic Abscess Due to Candida Tropicalis in a Nonacquired Immunodeficiency Syndrome Patient

We report a case of prostatic abscess due to Candida tropicalis in a nonacquired immunodeficiency syndrome patient with diabetes. The diagnosis and management are discussed, and the literature is reviewed.

Simultaneous repair of bilateral ureteropelvic junction obstruction.

Fifteen children with bilateral ureteropelvic junction obstruction underwent simultaneous repair as a single procedure. Dismembered pyeloplasty and ureterocalycostomy were the two procedures used. Ten were performed through anterior subcostal incisions. Posterior lumbotomy provided adequate exposure in 5 children and further contributed to shortened hospitalizations. The functional and anatomic results were excellent. Simultaneous bilateral pyeloplasty through posterior lumbotomy is a safe and cost-effective alternative to staged procedures for bilateral ureteropelvic junction obstruction.

Scrotal Island Flap Urethroplasty in the Management of Bulbar Urethral Strictures

We describe our experience with 20 patients undergoing 1-stage scrotal island flap urethroplasty for severe bulbomembranous stricture disease. While 16 patients achieved satisfactory results, 4 required revision for recurrent stricture, diverticulum or fistula. Use of hairless skin and aggressive tailoring of the flap are stressed to avoid the common complications of diverticulum, hair ball and stone formation. This highly vascularized pedicle represents a reasonable alternative to staged repair when local tissue scarring is great and free full thickness skin graft viability is questionable.

Primary amyloidosis of urethra.

Primary localized amyloidosis of the urethra is rare; only 17 cases reported to date. Its clinical importance is significant, however, in that its presentation mimics carcinoma and treatment should be conservative. We describe an additional case and briefly review the literature.

Experience with potency preservation during radical prostatectomy: Significance of learning curve

Potency preservation after radical prostatectomy is relatively new. The efficacy of this procedure has not been widely documented. Twenty-four patients with full potency underwent nerve-sparing radical prostatectomy. A total of 12 patients retained potency after surgery. Analysis of data reveals there is a learning curve in doing this procedure, and once the initial learning phase is over good results can be obtained in a select group of patients.