Reza S. Malek

HIGH POWER POTASSIUM-TITANYL-PHOSPHATE LASER VAPORIZATION PROSTATECTOMY

PURPOSE We prospectively studied a cumulative cohort of men with obstructive benign prostatic hyperplasia who underwent potassium-titanyl-phosphate (KTP) laser vaporization prostatectomy to determine the safety and efficacy of this procedure. MATERIALS AND METHODS A total of 55 men with symptomatic bladder outlet obstruction due to benign prostatic hyperplasia were treated with a 60 W. KTP laser produced by a prototype Laserscopedagger generator and delivered through a side-deflecting fiber with a 22Fr continuous flow cystoscope. Sterile water was used for irrigation. The prostatic lobes were vaporized to within capsular fibers. Mean lasing time plus or minus standard deviation was 44 +/- 19 minutes. RESULTS Mean prostate volume plus or minus standard deviation was 43 +/- 14 ml. No patient had any significant blood loss or fluid absorption, or required blood transfusion. Foley catheters did not require irrigation and were removed less than 24 hours postoperatively. All patients remained satisfied with voiding outcome, which changed significantly (p <0.0001). Mean improvement in American Urological Association symptom score at 3, 6, 12 and 24-month intervals was 75%, 79%, 82% and 82%, respectively. Mean increase in peak flow rate at the same intervals was 250%, 242%, 255% and 278%, respectively. Complications included mild transient dysuria in 7%, bladder neck contracture in 2% and delayed hematuria in 4% of patients. None of the patients required re-catheterization or reoperation, or had incontinence or newly developed impotence. Of the sexually active patients 15% and 9% had retrograde ejaculation at 1 and 2 years, respectively. CONCLUSIONS Our observation in a 2-year period indicates that 60 W. KTP laser vaporization prostatectomy is safe and effective for quickly relieving bladder outlet obstruction with minimal postoperative complications, a high rate of patient satisfaction and, to date, a generally good outcome.

Photoselective Vaporization of the Prostate: Initial Experience with a New 80 W KTP Laser for the Treatment of Benign Prostatic Hyperplasia

PURPOSE To study the safety and efficacy of a new high-power potassium-titanyl-phosphate laser (KTP/532; Niagara PV trade mark laser system; Laserscope, San Jose, CA) for transurethral photoselective vaporization of benign obstructive prostate tissue. PATIENTS AND METHODS The KTP/532 laser energy at 80 W was delivered by a 6F side-firing fiber through a 23F continuous-flow cystoscope. Photoselective vaporization of the prostate (PVP) using sterile water irrigation was performed under spinal anesthesia on an outpatient basis in 10 patients with a preoperative mean prostate volume of 41.37 +/- 18.5 cc (range 24-76.3 cc). The mean lasing time was 19.8 +/- 4.9 minutes. RESULTS Two patients experienced 1 to 7 days of mild dysuria, and one who was taking warfarin had mild transient hematuria, but none had urinary retention or other complications. The mean catheterization time was 17.2 +/- 9.6 hours (range 0-28 hours). At 1 year, the outcomes, which had showed significant improvement sustained throughout the follow-up, were as follows: mean American Urological Association Symptom Score decreased from 23.2 +/- 4.7 to 2.6 +/- 0.5 (88.8%), the mean quality of life score improved from 4.3 +/- 0.7 to 0.4 +/- 0.5 (90.7%), the mean peak urinary flow rate increased from 10.3 +/- 1.4 mL/sec to 30.7 +/- 5.8 mL/sec (198.1%), and the mean postvoiding residual volume decreased from 137.6 +/- 112.2 mL to 3.0 +/- 4.8 mL (97.8%). The mean prostate volume decreased by 27%. CONCLUSIONS This pilot study indicates that PVP with the new 80 W KTP/532 laser is a simple, safe, and efficacious outpatient procedure for the treatment of obstructive BPH.

Xanthogranulomatous Pyelonephritis: A Critical Analysis of 26 Cases and of the Literature

Manifestations of xanthogranulomatous pyelonephritis in 26 patients closely mimicked those of neoplastic and other inflammatory renal parenchymal diseases. Middle-aged or older women were affected most often. Most patients presented with anemia, chronic febrile illness, a painful tender flank mass and recurrent urosepsis. Some features of nephrogenic hepatic dysfunction were present in 13 patients. Bacterial cultures of renal tissue were almost always positive but the spectrum differed considerably from that of the bladder urine. Urographically, a renal mass lesion was encountered in 62% of the patients, nephrolithiasis in 38% and a functionless kidney in 27%. Angiographically, none of the 4 mass lesions studied was distinguished from hypernephroma. Indeed, a correct preoperative diagnosis was made in only 1 instance. There were 3 stages of xanthogranulomatous pyelonephritis recognized. Treatment consisted of nephrectomy for diffuse or advanced stage disease or both (21 patients), excision of the diseased renal segment for localized and low stage disease (2 patients) and renal biopsy (3 patients). Xanthogranulomatous pyelonephritis did not recur but in some patients bacteriuria continued or hypertension developed.

High-power potassium-titanyl-phosphate (KTP/532) laser vaporization prostatectomy: 24 hours later

OBJECTIVES To study the feasibility and immediate postoperative outcome of vaporization prostatectomy by high-power potassium-titanyl-phosphate (KTP/532) laser in 10 men with bladder outlet obstruction due to benign prostatic hyperplasia (BPH) and to evaluate their clinical and voiding outcome 24 hours postoperatively. METHODS The KTP/532 laser at 60 W was produced by a prototype Laserscope generator and delivered through a side-deflecting fiber with a 22F continuous-flow cystoscope. Sterile water was used for irrigation. The prostatic lobes were readily vaporized to within capsular fibers. The mean lasing time was 29 +/- 8 minutes, during which a mean of 104.6 +/- 30 kJ of energy was delivered. RESULTS The prostate volumes ranged from 22 to 60 mL (mean 38.4 +/- 9.7). None of the 10 patients had any significant blood loss or any fluid absorption. Foley catheters were removed in less than 24 hours postoperatively. All patients were satisfied with their voiding outcome. The mean peak urine flow rate increased from 8 +/- 1.3 mL/s preoperatively to 19.4 +/- 8.4 mL/s (142%, P = 0.003266) 24 hours postoperatively. Postvoid residual volumes remained essentially unchanged from their preoperative levels, as expected (P = 0.767423). One patient had urgency, but none had dysuria, hematuria, or incontinence or required recatheterization. Three patients have returned for 3-month follow-up; all 3 patients have had excellent results and are very satisfied with the outcome. CONCLUSIONS Our very early and limited experience indicates that high-power KTP/532 laser vaporization prostatectomy is feasible and appears to be safe and effective for quickly relieving bladder outlet obstruction due to BPH. Larger randomized clinical trials to compare this technique with standard transurethral resection of the prostate and more follow-up data are needed to determine its long-term efficacy and durability.

Potassium-titanyl-phosphate laser vaporization of the prostate: A comparative functional and pathologic study in canines

OBJECTIVE We compared the functional and pathologic results of potassium-titanyl-phosphate (KTP) laser vaporization prostatectomy with those of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser vaporization and coagulation prostatectomy in dogs. METHODS The prostates of 41 dogs were treated with KTP laser vaporization (n = 21), Nd:YAG laser vaporization (n = 10), or Nd:YAG laser coagulation (n = 10). Dogs were sacrificed 2 days or 8 weeks after treatment. Prostates were weighed, measured, serially sectioned, and whole-mounted for histologic analysis. RESULTS All techniques were hemostatic, and no irrigant absorption was detected. KTP laser vaporization produced a prostatic defect with a mean diameter of 3.0 and 2.4 cm at 2 days and 8 weeks postoperatively, respectively. Smaller defects (P < 0.0005 at 2 days and P < 0.02 at 8 weeks) were produced by Nd:YAG laser vaporization (2.0 and 1.4 cm, respectively) and coagulation (0.5 and 0.9 cm, respectively). No dog treated with KTP laser vaporization was incontinent or developed urinary retention, including 5 dogs whose urethral catheters were removed within 24 hours of surgery. CONCLUSIONS KTP laser vaporization prostatectomy not only provides hemostasis similar to that obtained with Nd:YAG laser coagulation, but also removes tissue at the time of operation, allowing dogs to void without straining within 24 hours of treatment. In addition, the procedure is technically simple, and the operator has excellent control over exactly which tissue is removed and which is left intact. These findings suggest that KTP laser vaporization may be useful in the treatment of human benign prostatic hyperplasia.

Angiomyolipoma: Clinical Metamorphosis and Concepts for Management

In 10 years the diagnosis of renal angiomyolipoma was made in 44 patients (female-to-male ratio 8:1) at our institution; 4 cases were associated with tuberous sclerosis. Of these patients 29 underwent surgical exploration because of a renal mass; 11 patients with renal masses that were consistent with angiomyolipoma radiologically have not undergone exploration. Of the 4 patients with and the 29 patients without tuberous sclerosis 1 (25 per cent) and 2 (7 per cent), respectively, had renal cell cancer in association with angiomyolipoma. Metachronous involvement of the contralateral kidney has not been noted in any of our patients who underwent nephrectomy for unilateral involvement, nor has there been progression of the contralateral lesion in 3 patients with bilateral disease without tuberous sclerosis during a followup of about 6 years. Furthermore, we have not noted progression of lesions in the 11 patients under observation for a mean followup of almost 3 years. We recommend elective exploration and a renal preserving operation when possible, not only for patients with pain and hemorrhage but also for the complex multiple lesions occasionally seen in patients who do not have tuberous sclerosis. Lesions associated with tuberous sclerosis require surgical intervention only when they become symptomatic or enlarge silently.

Primary Localized Amyloidosis of the Urinary Bladder: A Case Series of 31 Patients

OBJECTIVE To evaluate the presentation and prognosis of primary localized amyloidosis of the urinary bladder. PATIENTS AND METHODS The medical records of 31 patients with primary localized amyloidosis of the urinary bladder were reviewed. Immunohistochemical amyloid typing was performed on bladder biopsy specimens from 27 patients. RESULTS The median age of the 22 men and 9 women was 55 years. Twenty-four patients (77%) presented with gross hematuria (associated with irritative urinary tract symptoms in 6 patients), and 7 (23%) had only irritative lower urinary tract symptoms. Multiple bladder areas were involved in 20 patients (65%), a single area was involved in 8 (26%), and diffuse involvement was present in 3 (10%). Twenty-four patients had immunoglobulin light chain, and 3 had transthyretin-related amyloid. Local recurrences were common. None of the patients developed systemic amyloidosis. CONCLUSION Primary localized amyloidosis of the urinary bladder can be easily confused with a neoplasm. Immunohistochemical amyloid typing is important. Transthyretin-related amyloid of the bladder requires no further work-up. Repeated work-ups for systemic amyloidosis are unnecessary for patients with light chain-related amyloidosis of the urinary bladder. Early eradication with fulguration or laser therapy is indicated. Cystoscopic follow-up is necessary.

High-power (60-watt) potassium-titanyl-phosphate laser vaporization prostatectomy in living canines and in human and canine cadavers

OBJECTIVES We studied the safety and efficacy of 60-W potassium-titanyl-phosphate (KTP) laser prostatectomy in living dogs and compared the efficacy with that in fresh human and dog cadavers. METHODS Ten dogs underwent 60-W KTP laser prostatectomy and were sacrificed 3 hours (n = 5) or 7 weeks (n = 5) after operation. Two thawed fresh-frozen human cadaver prostates and two thawed fresh-frozen canine prostates were also vaporized with the 60-W KTP laser. All prostates were weighed, measured, serially sectioned, and whole mounted for histologic analysis. RESULTS In dogs, the in vivo procedure was hemostatic, and no irrigant absorption was detected. Prostatic defects with a mean diameter of 3.0 and 2.5 cm at 3 hours and 7 weeks postoperatively, respectively, were produced. With experience, resection time was reduced to 14 minutes. Of the 5 dogs that were studied for 7 weeks, 4 voided immediately after removal of the urethral catheter on the morning after operation, and 1 dog required recatheterization but voided with a strong stream when the urethral catheter was removed 4 days later. All 5 dogs were continent and had normal erectile function postoperatively. Defects of 2.0 and 2.5 cm were produced in the two human cadaver prostates (weight, 29.5 and 55 g) with resection times of 26 and 54 minutes, respectively. Human and canine cadaver prostates required similar energies for tissue vaporization (15.2 and 13.7 kJ/cm3 cavity created, respectively, P > 0.6), whereas living canine prostates required only 7.0 kJ/cm3 cavity created (P < 0.01 compared with cadaver tissue). CONCLUSIONS The 60-W KTP laser allows technically easy, safe, rapid, and hemostatic removal of canine prostatic tissue in vivo. Furthermore, there is no difference in the efficacy of KTP laser vaporization between human and canine cadaver prostates. These findings suggest that KTP laser vaporization may be as effective in living human prostates as it is in living dogs, and thus it may be a useful technique in the surgical treatment of human benign prostatic hyperplasia.

Laser therapy of squamous cell dysplasia and carcinoma of the penis

OBJECTIVES To analyze the influence of etiologic factors and practical issues regarding the merits, limitations, and long-term results of aggressive laser treatment of premalignant and malignant squamous cell lesions of the penis. METHODS Preparation of genital skin with 5% acetic acid and mapping biopsies of lesions and the surrounding field-of-change were performed in 52 men evaluated and subsequently treated with laser during a 10-year period. Most men (81%) were or had been smokers, and many (46%) had female sexual partners infected with human papillomavirus. Carbon dioxide laser was used for low-stage lesions; potassium-titanylphosphate/532 or neodymium:yttrium-aluminum-garnet laser was used for more histologically advanced lesions. Not only the lesions but also the entire human papillomavirus-induced field-of-change was treated. Circumcision was performed simultaneously in 28 previously uncircumcised patients. RESULTS All lesions demonstrated aceto-whitening and histologic changes of human papillomavirus infection. Human papillomavirus DNA was detected in 93.5% of the specimens from 31 patients studied. Of the 52 patients, 22 (42%) had dysplastic premalignant penile intraepithelial neoplasia, and the remaining 30 (58%) had squamous cell carcinoma. Forty-four patients were available for follow-up from 12 to 117 months (average 58). Overall, 5 patients (11.4%) experienced a recurrence: 3 were successfully re-treated with laser, and 2 patients underwent partial penectomy, 1 of whom with squamous cell carcinoma Stage T2 died of metastatic disease. CONCLUSIONS Aggressive laser therapy of the visible lesions and of the entire dysplastic premalignant field-of-change produces excellent cosmetic results. The entire penis and, therefore, its full sexual functional potential are preserved. The low rate of local recurrence over the long term in all but deeply invasive (T2) lesions compares favorably with the outcome of other, more conventional therapies. Irrespective of therapeutic approach, close and long-term surveillance of all patients and counseling for their sexual partners are mandatory.

Renal cell carcinoma in von hippel-lindau syndrome

Thirty-seven cases of von Hippel-Lindau syndrome are reported. The urinary tract was studied in 23 patients; 15 of them had the renal lesions. Eight of these 15 patients had renal cell carcinoma, which was bilateral in six. Because 80 percent of these patients are seen initially by neurologists or ophthalmologists, the potential for the development of renal cell carcinoma in these patients, the familial nature of the disorder, and the need for early urologic investigations and subsequent close follow-up are emphasized.