This Month in Adult Urology

Article Outline

• Serum Antisperm Antibodies to Diagnose Post-Vasectomy Obstructive Azoospermia
• Endothelial Function and Oxidative Stress After Sildenafil in Type 2 Diabetic Men With Erectile Dysfunction
• Sildenafil Citrate in Men With Multiple Sclerosis
• Neoadjuvant Combined Therapy for High Risk Localized Prostate Cancer
• Sexual Function Outcomes After Nerve Sparing Robot Assisted Radical Prostatectomy
• Manuscript Publication by Urology Residents and Predictive Factors
• Type 2 Diabetes Mellitus and Risk of Urinary Incontinence
• Percutaneous Nephrostolithotomy in Anticoagulated Patients
• Factors Influencing Renal Function Reduction After Partial Nephrectomy
• Visually Directed Transrectal High Intensity Focused Ultrasound for Prostate Cancer
• Copyright

Back to Article Outline

Serum Antisperm Antibodies to Diagnose Post-Vasectomy Obstructive Azoospermia 

Determining the causes of azoospermia can be invasive, even requiring testis biopsy. Lee et al (page 264) from New York, New York report on 272 men with obstruction of the vas deferens or epididymis, of whom 212 had documented infertility without azoospermia. The authors analyzed immunoglobulins G, A and M in the serum, and found that IgG had the highest sensitivity at 85%, with a specificity of 97% for obstruction. They were able to show that antisperm antibodies are highly accurate and useful in predicting obstructive azoospermia, particularly after vasectomy. Such a test may obviate the need for testis biopsy or vasography.

Back to Article Outline

Endothelial Function and Oxidative Stress After Sildenafil in Type 2 Diabetic Men With Erectile Dysfunction 

Erectile dysfunction (ED) in a large percentage of men is thought to be due to endothelial dysfunction. Drugs such as the phosphodiesterase type 5 (PDE5) inhibitors may influence the endothelium and thus exert long-term effects on the vasculature. Burnett et al (page 245) from Baltimore, Maryland assessed 148 type 2 diabetic men for the endothelial function marker cyclic guanosine monophosphate (cGMP), free radical damage (8-isoprostane) and inflammation (interleukin-6 and 8). Erectile function was assessed using the Sexual Encounter Profile. The cGMP levels were increased compared to those of a placebo group after daily doses of 50 mg sildenafil for 1 week and 100 mg sildenafil for 3 weeks. These increased levels correlated with positive responses on the Sexual Encounter Profile. Furthermore, serum 8-isoprostane levels decreased but interleukin-6 and 8 levels were unchanged. However, the decreased 8-isoprostane was not statistically significant. Thus, previous suggestions that continued use of oral vasoactive therapies may have vasoprotective benefits against cardiovascular disease are possible given that cGMP levels remained increased for weeks after cessation of sildenafil.

The authors attribute some of the therapeutic benefits to the effect on endothelium. However, those effects are limited to active drug dosing during and up to 4 to 8 weeks after treatment. There is no prolonged beneficial effect on erectile function once the drug is stopped. An explanation for this finding may be the mild to moderate ED in the diabetic population studied. It should also be noted that in the placebo group as needed use of PDE5 inhibitors was allowed, and so the comparison groups were continuous use vs as needed use.

Back to Article Outline

Sildenafil Citrate in Men With Multiple Sclerosis 

Recent studies have suggested that sildenafil is beneficial for treating ED in men with multiple sclerosis. In contrast, Safarinejad (page 252) from Islamic Republic of Iran found no beneficial effects of sildenafil using the Global Assessment Questionnaire. Of 203 patients with multiple sclerosis and ED 102 received 50 mg sildenafil and 101 received placebo. A beneficial effect was reported by 32.8% of the patients on sildenafil vs 17.6% on placebo. A previous report indicated an 89% response rate. Although the explanation for the difference is not obvious, it is possible that these individuals either had more severe multiple sclerosis or coexisting factors affecting ED despite attempts to exclude patients with such factors from the study.

Back to Article Outline

Neoadjuvant Combined Therapy for High Risk Localized Prostate Cancer 

Animal studies indicate that therapeutic inhibition of platelet-derived growth factor receptor with imatinib mesylate in combination with taxane chemotherapy enhances vascular endothelial apoptosis and increases tumor kill, producing delayed progression of bone micrometastases. Based on this observation, Mathew et al (page 81) from Galveston, Texas examined the combination in a nonplacebo controlled trial of 36 men with cT2 or greater, Gleason grade 8–10 disease and serum prostate specific antigen (PSA) greater than 20 ng/ml or stage cT2, Gleason 7 disease and PSA greater than 10 ng/ml without evidence of metastases. These high risk patients received leuprolide, daily imatinib and weekly docetaxel every 42 days for 3 cycles before radical prostatectomy. Patients were evaluated for complete pathological response. However, at a median followup of 39 months only 53% were free of disease progression and no complete responders were identified. Thus the authors, despite promising animal data, were not able to confirm that this novel preoperative chemotherapy regimen had a beneficial effect on cancer outcomes.

Back to Article Outline

Sexual Function Outcomes After Nerve Sparing Robot Assisted Radical Prostatectomy 

There continues to be great enthusiasm for robotic assisted laparoscopic radical prostatectomy, and extremely high rates of potency have been reported after nerve sparing radical prostatectomy using the da Vinci® robot. Rodriguez et al (page 259) from Orange, California sought to define more precisely erectile function in a select group drawn from 200 consecutive men undergoing robot assisted laparoscopic prostatectomy between July 2004 and February 2006. Patients were selected if they were younger than 65 years old, had a normal baseline International Index of Erectile Function (IIEF-5) score and completed a 2-year followup. A total of 58 men met these criteria and were followed. Potency was defined as an affirmative answer to 2 questions on the EPIC-24 questionnaire. Men who achieved erection using either vacuum devices or alprostadil were considered impotent. However, men who achieved erections using sildenafil, which was initiated nightly as early as 1 week after surgery, were considered potent. Of the men on sildenafil 32.1% reported potency at 3 months. At 24 months potency was 89.7% overall, with rates of 93% for bilateral nerve sparing and 80% for unilateral nerve sparing procedures. The potent men reported IIEF-5 scores averaging 20.4 at 2 years and erectile firmness was 91% of baseline values. The authors did not find any statistical difference in IIEF-5 scores between men treated with unilateral or bilateral nerve sparing procedures. Although this study represents a select group of men with highly defined criteria for success, results confirm that after nerve sparing procedures using robotic assistance, high levels of potency can be achieved in combination with early institution of PDE5 inhibitors. These results need further confirmation in large prospective trials.

Back to Article Outline

Manuscript Publication by Urology Residents and Predictive Factors 

Hellenthal et al (page 281) from Davis, California surveyed 255 chief residents and recent graduates of 83 accredited urological training programs in the United States and Canada to ascertain predictive factors for production of scientific manuscripts. They found that 81% of residents submitted at least 1 academic paper to a peer reviewed journal during or shortly after completing residency. Not surprisingly, greater amounts of protected research time were associated with greater productivity in terms of peer reviewed manuscripts. While there was no difference if dedicated research time was 3 or 6 months (average number of manuscripts submitted was 3 vs 4, respectively), residents who had 1 year of dedicated research time had submitted more than double the manuscripts (an average of 7 manuscripts) compared to those with only 3 months of dedicated research time. Overall, the median number of manuscripts accepted by peer reviewed journals was 2. It appears that dedicated research time dramatically increases the number of publications. Other variables such as PhD status or publication during medical school were not significant. Reductions in resident work hours and designated research time have profound implications for academic productivity by training programs.

Back to Article Outline

Type 2 Diabetes Mellitus and Risk of Urinary Incontinence 

It is well-known that patients with diabetes suffer from a wide range of voiding complaints. For example, many diabetic women have some degree of urinary incontinence (UI). Danforth et al (page 193) from Boston, Massachusetts examined participants enrolled in the Nurses' Health Study between 1976 and 2000, and between 1989 and 2001. Women with UI weekly were identified in the 2000 to 2002 and 2001 to 2003 cohorts. When these 2 cohorts were analyzed the authors found that at least 5.3% of women without type 2 diabetes had weekly incontinence compared to 8.7% of those with diabetes. This increase in UI was largely explained by greater odds of urge UI (odds ratio 1.4, 95% CI 1.0–1.9, p=0.03). There was no association between diabetes and stress or mixed UI. Thus, the authors conclude that type 2 diabetes may predispose women to urge incontinence.

Back to Article Outline

Percutaneous Nephrostolithotomy in Anticoagulated Patients 

Increasing use of anticoagulants raises logistical problems for surgeons and may be associated with greater intraoperative or postoperative morbidity. In a review of the records of 792 patients undergoing percutaneous nephrostolithotomy (PCNL) at Cleveland Clinic Kefer et al (page 144) identified 27 patients on anticoagulant therapy with either warfarin, clopidogrel or cilostazol, who underwent surgery following perioperative reversal and re-initiation of anticoagulation. Warfarin was stopped 5 days preoperatively, whereas clopidogrel and cilostazol were stopped 10 days preoperatively. All anticoagulants were reinstituted 5 days postoperatively. Overall, the stone-free rate after PCNL monotherapy was 93% in patients on anticoagulation. Mean hemoglobin decreased 1.5 gm/dl and mean change in serum creatinine was 0.03 mg/dl, similar to that of other patients. Only 2 patients had significant bleeding and 1 had a thromboembolic complication. The authors suggest that with careful planning, patients on anticoagulation therapy can safely undergo PCNL.

Back to Article Outline

Factors Influencing Renal Function Reduction After Partial Nephrectomy 

With increasing use of partial nephrectomy to preserve renal function, it is important to understand the variables that place the patient at greater risk for impaired renal function after nephron sparing surgery. Song et al (page 48) from Seoul, Republic of Korea examined 117 patients who elected partial nephrectomy (laparoscopic and open) using the diethylenetetramine-pentaacetic acid renal scan to measure glomerular filtration rate (GFR) before and 6.5 months after surgery. Multivariate analysis revealed that renal volume reduction as determined by computerized tomography was the most significant prognosticator for GFR reduction followed by polar location of tumor, upper vs lower pole and older age. Thus a greater amount of reduction in renal mass, upper pole location and older age predicted the greatest reduction in renal function. The authors found that operation time and warm ischemia time were significantly longer in the laparoscopic group compared to the open group. The degree of GFR reduction was similar for both surgeries (35.8 vs 36.4 cm²). The authors conclude that both methods can be successful.

Back to Article Outline

Visually Directed Transrectal High Intensity Focused Ultrasound for Prostate Cancer 

High intensity focused ultrasound (HIFU) has been around since the 1990s as a treatment for benign prostatic hyperplasia initially and then for prostate cancer. Reports continue to show that it may have some role in prostate cancer although current therapies are not approved for use in the United States. Mearini et al (page 105) from Perugia, Italy report their experience with 163 consecutive men with T1-T3 N0M0 prostate cancer treated with HIFU. PSA was measured 1 month after treatment and every 3 months subsequently. The authors classified 80 patients as low risk, 47 as intermediate risk and 14 as high risk for prostate cancer. The procedure took a mean of 189 minutes. At 6 months after therapy the positive prostate biopsy rate was 33.9%. According to risk stratification, the negative biopsy rate for low, intermediate, high and very high risk was 75.5%, 77.4%, 35.7% and 18.7%, respectively. The 3-year biochemical disease-free rates for the same risk groups were 86.1%, 79.6%, 56.4% and 19.6%, respectively. It is significant that 16% of patients had mixed urinary incontinence and 1 had grade 3 stress incontinence after HIFU. Urethral stricture disease developed in 24 patients (15%) and a recto-urethral fistula requiring urinary diversion occurred in 1. Thus morbidity was substantial even for this minimally invasive procedure. It remains to be seen what role HIFU will have in prostate cancer after further reports.