Effect of pulse width variations on sacral neuromodulation for overactive bladder symptoms: A prospective randomized crossover feasibility study

INTRODUCTION/BACKGROUND

The pulse width (PW) parameter in sacral neuromodulation (SNM) is understudied, with no evidence-based guidance available on optimal PW for urinary indications. The aim of this prospective, randomized, single-blinded, 3 × 3 cross over design study was to estimate the effect of two PW settings (60 µs, 420 µs) compared to the industry standard (210 µs) on SNM efficacy, quality of life, and device parameters in patients who were stable and satisfied with their SNM treatment.

METHODS/MATERIALS

Eligible patients were previously implanted and had urge incontinence or urgency-frequency with satisfaction on SNM at time of enrollment. Patients completed a 3-day voiding diary, validated questionnaires, and device interrogations with sensory threshold assessment at baseline and after a 4-week period on each of the three PW settings, to which they were randomized. Eighteen participants completed the study, as called for by power analysis.

RESULTS

Eighteen patients were enrolled in the study. Mean age was 68 years and implant duration at the time of participation was 4.4 years. While PW variations did not produce significant differences in overall objective outcomes, device parameters, including sensory threshold amplitude and battery life differed significantly. Shortened PW necessitated higher amplitude while conserving battery life. Stimulus sensation location, quality, and intensity did not differ between PW. Standard PW was chosen by 11 patients after the study, 5 chose extended, and 2 chose shortened. Those who chose alternative PW achieved significant reductions in urinary frequency from enrollment -2.23 voids/day (p = 0.015). Upon sub-analysis, patients reporting "much better" or "very much better" on extended PW achieved significant reductions in urinary frequency and nocturia at 5.6 and 0.4, compared to 8.5 and 2.16 at baseline (p = 0.005, p = <0.001). Whereas those reporting "much better" or "very much better" on shortened PW achieved significant reductions in urinary frequency at 5.15 compared to 7.35 (p = 0.026). There were no adverse events or complications.

CONCLUSIONS

Overall SNM effectiveness was unchanged with alternative PW; however, 39% of patients preferred alternative to standard PW and achieved significant improvements in urinary symptoms with such. Shorter PW can also provide savings in estimated battery life without sacrificing therapeutic efficacy.

The role of pulse width manipulation compared to program changes alone for unsatisfactory sacral neuromodulation therapy: A retrospective matched-cohort analysis

AIM

Pulse width (PW) influences neuromodulation by its impact on nerve fiber recruitment. A paucity of data regarding the manipulation of PW in sacral neuromodulation (SNM) exists. This study describes the clinical features and outcomes of PW manipulation for unsatisfactory SNM therapy.

METHODS

A retrospective, single-institution review was performed of reprogrammed SNM patients between 2010 and 2019. Two cohorts were created: those with PW changes ± program changes and age-matched controls with program changes alone. Patients lacking follow-up and non-InterStim II models were excluded.

RESULTS

Out of 710 SNM interrogations, 147 (20.7%) had PW changes and 80 met inclusion criteria. Most PW changes were shortened (61/80, 76.3%). Clinical features did not differ between cohorts except by indication for reprogramming. The most common indication for PW change was painful stimulation (34/80, 43%), whereas in controls it was suboptimal efficacy (76/80, 95%). Clinical success was stratified by indication. There was a higher improvement in efficacy in the PW cohort (61%, 17/28 vs. 36%, 27/76, p = .02). PW manipulation successfully relieved painful stimulation in 50% (17/34 vs. 0/3, p = .23), which was more likely with a shortened compared to extended PW (14/15, 93.3% vs. 0/6, 0%, p < .01). PW resulted in improvement in localization of the stimulus in 94% (17/18 vs. 0/1, p = .10). The subsequent lead revision or explant was significantly higher in the PW cohort (43% vs. 25%, p = .03).

CONCLUSION

PW manipulation may aid the salvage of unsatisfactory SNM therapy. These findings represent an initial assessment of the role of PW in SNM, particularly regarding the efficacy and painful stimuli. The further prospective investigation is warranted.

Impact of parturition on chemokine homing factor expression in the vaginal distention model of stress urinary incontinence

PURPOSE

Human childbirth simulated by vaginal distention is known to increase the expression of chemokines and receptors involved in stem cell homing and tissue repair. We hypothesized that pregnancy and parturition in rats contributes to the expression of chemokines and receptors after vaginal distention.

MATERIALS AND METHODS

We used 72 age matched female Lewis rats, including virgin rats with and without vaginal distention, and delivered rats with and without vaginal distention. Each rat was sacrificed immediately, or 3 or 7 days after vaginal distention and/or parturition, and the urethra was harvested. Relative expression of chemokines and receptors was determined by real-time polymerase chain reaction. Mixed models were used with the Bonferroni correction for multiple comparisons.

RESULTS

Vaginal distention up-regulated urethral expression of CCL7 immediately after injury in virgin and postpartum rats. Hypoxia inducible factor-1α and vascular endothelial growth factor were up-regulated only in virgin rats immediately after vaginal distention. CD191 expression was immediately up-regulated in postpartum rats without vaginal distention compared to virgin rats without vaginal distention. CD195 was up-regulated in virgin rats 3 days after vaginal distention compared to virgin rats without vaginal distention. CD193 and CXCR4 showed delayed up-regulation in virgin rats 7 days after vaginal distention. CXCL12 was up-regulated in virgin rats 3 days after vaginal distention compared to immediately after vaginal distention. Interleukin-8 and CD192 showed no differential expression.

CONCLUSIONS

Vaginal distention results in up-regulation of the chemokines and receptors expressed during tissue injury, which may facilitate the spontaneous functional recovery previously noted. Pregnancy and delivery up-regulated CD191 and attenuated the expression of hypoxia inducible factor-1α and vascular endothelial growth factor in the setting of vaginal distention, likely by decreasing hypoxia.

Co-morbidities of interstitial cystitis

Introduction: This study aimed to estimate the proportion of patients with interstitial cystitis/painful bladder syndrome (IC/BPS) with systemic dysfunction associated co-morbidities such as irritable bowel syndrome (IBS) and fibromyalgia (FM). Materials and Methods: Two groups of subjects with IC/BPS were included: (1) physician diagnosed patients with IC/BPS and (2) subjects meeting NIDDK IC/PBS criteria based on a questionnaire (ODYSA). These groups were compared to healthy controls matched for age and socio-economic status. NIDDK criteria required: pain with bladder filling that improves with emptying, urinary urgency due to discomfort or pain, polyuria >11 times/24 h, and nocturia >2 times/night. The ODYSA instrument evaluates symptoms pertaining to a range of disorders including chronic fatigue, orthostatic intolerance, syncope, IBS, dyspepsia, cyclic vomiting syndrome, headaches and migraines, sleep, Raynaud’s syndrome, and chronic aches and pains. Results: IC/BPS was diagnosed in 26 subjects (mean age 47 ± 16 years, 92% females), 58 had symptoms of IC/BPS by NIDDK criteria (mean age 40 ± 17 years, 79% females) and 48 were healthy controls (mean age 31 ± 14 years, mean age 77%). Co-morbid complaints in the IC/BPS groups included gastrointestinal symptoms suggestive of IBS and dyspepsia, sleep abnormalities with delayed onset of sleep, feeling poorly refreshed in the morning, waking up before needed, snoring, severe chronic fatigue and chronic generalized pain, migraines, and syncope. Discussion: Patients with IC/BPS had co-morbid central and autonomic nervous system disorders. Our findings mirror those of others in regard to IBS, symptoms suggestive of FM, chronic pain, and migraine. High rates of syncope and functional dyspepsia found in the IC/BPS groups merit further study to determine if IC/BPS is part of a diffuse disorder of central, autonomic, and sensory processing affecting multiple organs outside the bladder.

Cytokine expression after vaginal distention of different durations in virgin Sprague-Dawley rats

PURPOSE

We investigated the effect of the duration of vaginal distention on the differential expression of stem cell homing, tissue repair cytokines and cytokine receptors to identify the factors most important for recovery from injury.

MATERIALS AND METHODS

A total of 20, 10-week-old virgin Sprague-Dawley rats were divided into 4 groups, including 1, 4 and 6-hour vaginal distention, and anesthetized sham operation. The vagina, bladder, urethra and rectum were harvested immediately after vaginal distention. Real-time polymerase chain reaction was used to determine the relative expression of cytokines and receptors of interest. Mixed models analysis was used to determine associations between expression levels and vaginal distention duration.

RESULTS

Positive associations between vaginal distention duration and the urethral expression level were found for 1 of the receptors of monocyte chemotactic protein-3, CCR1 (p = 0.0001) as well as for monocyte chemotactic protein-3 (p = 0.025), CCR5 (p = 0.032) and hypoxia inducible factor-1alpha (p = 0.023). A positive relationship between vaginal distention duration and monocyte chemotactic protein-3 expression was also observed in rectal tissue (p = 0.035). Urethral expression of CCR2, another receptor for monocyte chemotactic protein-3, approached significance (p = 0.066). An inverse relationship between vaginal distention duration and interleukin-8 expression was found in the bladder (p = 0.0008). No association was noted between vaginal distention duration and the expression of stromal derived factor-1, CXCR4, CCR3 and vascular endothelial growth factor in any pelvic organs.

CONCLUSIONS

These data support a relationship between vaginal distention duration and the subsequent expression of monocyte chemotactic protein-3 and 1 of its associated receptors, CCR1, in the urethra immediately following vaginal distention. The increase in hypoxia-inducible factor1alpha expression in the urethra with prolonged vaginal distention suggests a limited role of tissue ischemia in the immediate response of pelvic organs to vaginal distention.

Evaluating and managing urinary incontinence after prostatectomy: beyond pads and diapers

Men who become persistently incontinent after undergoing prostatectomy have a variety of options for regaining control, ranging from behavioral changes to surgery. To determine the best therapy, one should define the problem with a thorough urologic evaluation.

Fluoroquinolone resistance in Ureaplasma parvum in the United States

We report the first case of naturally occurring fluoroquinolone resistance in Ureaplasma spp. from the United States. Resistance in this case probably developed as a result of mutations in the gyrA and parC genes of the DNA gyrase/topoisomerase IV complex that occurred in the presence of antimicrobial selective pressure.

Complications and troubleshooting of two-stage sacral neuromodulation therapy: A single-institution experience

OBJECTIVES

With the increasing use of sacral neuromodulation therapy, urologists are faced with postimplantation challenges. The purpose of this study was to identify these events and their causes and management in our large single-institution experience.

METHODS

From July 2002 to September 2004, all patients who underwent sacral neuromodulation therapy for refractory bladder conditions were identified. Their medical records were retrospectively evaluated for history, operative intervention, and programming visits. Events after implantation of the implantable pulse generator (IPG) unit were noted. The evaluation, troubleshooting, management, and resolution of events at the last follow-up visit were extracted.

RESULTS

A total of 214 patients underwent sacral neuromodulation therapy at our institution. The mean patient age was 53.5 +/- 15.4 years. Of the 214 patients, 161 underwent IPG implantation during a mean follow-up period of 16 months (range 5 to 30). The second-stage explantation and revision rate was 10.5% and 16.1%, respectively. The indications for explantation were infection (8 of 17) and failure to maintain a response (9 of 17). Revisions were done for decreases in response with abnormal (12 of 26) or normal (5 of 26) impedance measurements, IPG site discomfort (4 of 26), draining sinus at the IPG site (4 of 26), and lead migration (1 of 26). Equalization of impedance measurements was the most commonly observed impedance abnormality. These were managed by drying fluid from the connection in 4 patients and lead change in the rest.

CONCLUSIONS

After IPG implantation, a decline in response may occur. Although some were explanted, most were revised, with most of the revisions functional on follow-up. Familiarity with impedance evaluation and development of algorithms for postimplant management are essential for troubleshooting and maintenance of the device.

Nighttime dosing with tolterodine reduces overactive bladder-related nocturnal micturitions in patients with overactive bladder and nocturia

OBJECTIVES

To evaluate the efficacy and tolerability of nighttime tolterodine dosing on urgency-related micturitions in patients with overactive bladder (OAB) and nocturia.

METHODS

This was a 12-week randomized controlled study of 850 patients given 4 mg tolterodine extended release (TER) or placebo once daily 4 hours or less before bed. Patients with eight or more micturitions/24 hours and a mean of 2.5 episodes/night or more were included. Changes in the number of nighttime and 24-hour micturitions were analyzed by urgency rating per micturition. The urgency per micturition was recorded in 7-day diaries using a 5-point rating scale (score 1 to 5). Each micturition was classified according to the following urgency rating categories: total (1 to 5), non-OAB (1 to 2), or OAB (3 to 5). OAB-related micturitions were further classified as nonsevere (score 3) and severe (score 4 to 5).

RESULTS

TER reduced the total number of nocturnal micturitions, but, compared with placebo, this difference was not statistically significant. However, TER did significantly reduce OAB-related and severe OAB-related nocturnal micturitions compared with placebo. TER had no effect on non-OAB micturitions. TER significantly reduced the total, OAB, and severe OAB micturitions during 24-hour and daytime intervals compared with placebo. Significantly more TER-treated than placebo-treated patients reported a treatment benefit and willingness to continue treatment. Adverse events associated with nighttime dosing of TER versus placebo were few.

CONCLUSIONS

TER significantly reduced OAB-related micturitions during 24-hour, daytime, and nighttime intervals. TER did not affect normal (non-OAB) micturitions. Nighttime dosing with TER was associated with few adverse events and adverse event-related withdrawals. The 24-hour efficacy of TER was maintained with nighttime dosing.

Buccal mucosa graft urethroplasty for recurrent stricture of female urethra

Recurrent stricture of the female urethra is an uncommon, yet difficult, condition to manage. This report demonstrates a ventral buccal mucosa onlay graft technique as a feasible and reliable method of repairing this condition.

Neurovascular preservation in orthotopic cystectomy: Impact on female sexual function

OBJECTIVES

The published data regarding female orthotopic cystectomy have focused primarily on urethral recurrence and urinary continence. In a new era of sexuality, evaluating postoperative sexual outcome has become a new surgical endpoint. In this study, we focused on the impact of neurovascular preservation after radical cystectomy and neobladder construction.

METHODS

We assessed female sexuality in 13 patients after orthotopic cystectomy using a standardized questionnaire, Female Sexual Function Index (FSFI). Six patients had undergone nerve-sparing cystectomy and seven had undergone contemporary non-nerve-sparing cystectomy. Intraoperatively, the tumor was deemed oncologically safe for neurovascular preservation. All 13 patients were sexually active preoperatively, were younger than 65 years old, had recurrence-free follow-up findings after 1 year, and had undergone no pelvic irradiation. The 19-item FSFI questionnaire analyzed six domains (desire, arousal, lubrication, orgasm, satisfaction, and pain) of sexual function.

RESULTS

In the nerve-sparing group (mean age 55.9 years), the baseline and 12-month postoperative scores showed a minimal decline in results, with a total mean FSFI score of 24.5 versus 22.3, respectively. In analyzing each of the six domains, no significant decline or difference was observed. Conversely, in the non-nerve-sparing group (mean age 56.7 years), a significant decline or difference was found in the 12-month total mean FSFI scores between the baseline and postoperative FSFI scores (25.0 versus 11.0, respectively). In the non-nerve-sparing group, 6 of 7 patients ultimately discontinued sexual intercourse.

CONCLUSIONS

Female sexual function was preserved in patients who received neurovascular preservation. In contrast, all domains of sexual function declined in patients who had undergone non-neurovascular preservation.

Urologic applications of botox

Botulinum toxin (BTX), a neurotoxin produced by the gram-positive, rod-shaped anaerobic bacterium Clostridium botulinum, was isolated in 1897 by Belgian scientist Professor Pierre Emile van Ermengem. BTX acts by blocking the release of acetylcholine at the neuromuscular junction. As a result of this chemodenervation, a temporary flaccid paralysis ensues. Different medical disciplines have taken advantage of this temporary paralysis to treat muscular hypercontraction. BTX was first approved by the US Food and Drug Administration in 1989 for use in patients with strabismus and blepharospasm. Since then, BTX has been used to treat a number of different neuromuscular disorders. Although not approved by the US Food and Drug Administration, BTX has been used successfully in urology to treat neurogenic and non-neurogenic detrusor overactivity, detrusor-sphincter dyssynergia, motor and sensory urge, and chronic pain syndromes.

Management of ureteral injuries associated with vaginal surgery for pelvic organ prolapse

Due to the anatomic proximity of the urinary and genital tracts, iatrogenic ureteral injury during pelvic organ prolapse repairs is a serious complication that we have managed in increasing number at our institution. However, few centers have reported on their experience with ureteric injuries associated with gynecologic reconstructive surgery. These ureteral injuries may lead to much morbidity, in particular the formation of ureterovaginal fistula, and the potential loss of renal function especially when diagnosed postoperatively. It is necessary, therefore, for surgeons to have a thorough knowledge of ureteral anatomy and to take precautions to prevent such injuries. The purpose of this article is to review this pertinent anatomy and the key principles of management of ureteric complications of transvaginal surgery for pelvic organ prolapse. The present study illustrates the application of our treatment algorithm based on the time of presentation and the patient condition.

Urologic applications of botulinum toxin therapy for voiding dysfunction

Botulinum toxin is primarily a presynaptic neuromuscular blocking agent inducing selective and reversible muscle weakness up to several months when injected intramuscularly in small quantities. The clinical use of botulinum toxin type-A has gained widespread acceptance and application for numerous adult and pediatric spasticity syndromes. This has led to the urologic adoption of this minimally invasive therapy for the treatment of idiopathic and neurogenic detrusor overactivity, interstitial cystitis, detrusor-sphincter dyssynergia, urinary retention, and prostatic conditions. Outlined below is an overview of the clinical adoption of this therapy for the treatment of various dysfunctions of the lower urinary tract.

Incidence of pubic osteomyelitis after bladder neck suspension using bone anchors

OBJECTIVES

To determine the incidence of pubic osteomyelitis after bladder neck suspension using suprapubic bone anchors.

METHODS

The target population consisted of 290 consecutive women who underwent bladder neck suspension using suprapubic bone anchors between June 1994 and November 1999 at two referral centers. A structured telephone questionnaire was designed to elicit any history of clinical symptoms suspicious for pubic osteomyelitis. Positive responses were followed up by a detailed review of the medical records. Nonresponders were evaluated by chart review, with negative cases included only if the documented follow-up reached 1 year.

RESULTS

The sample consisted of 225 women, representing 77.6% of the study population, with a mean age of 69.7 years (range 40 to 88) and a mean follow-up of 31.8 months (range 13.4 to 42.2). Of the 225 women, 179 (80%) completed the telephone survey; 46 patients (20%) were evaluated by long-term chart review. Three patients (1.3%) reported positive responses to the screening questionnaire and were confirmed to have developed pubic osteomyelitis. Each had undergone exploratory laparotomy, anchor removal, bony debridement, and prolonged parenteral antibiosis. The most common noninfectious complaints were irritative voiding symptoms and pubic or groin pain responding to "conservative" therapy (3.5%), including 1 case of osteitis pubis. One subject underwent repeated operation because of erosion of the sling sutures into the bladder.

CONCLUSIONS

The estimated incidence of osteomyelitis after bone-anchored bladder neck suspension was 1.3%. Although postoperative osteomyelitis is rare, each case incurs substantial morbidity and a complicated postoperative course.

The safety of reusing injectable collagen: a multicenter microbiological study

We have previously reported pilot data regarding the safety of saving partially used syringes of a glutaraldehyde cross-linked collagen for use in subsequent treatment sessions with the same individual. That single institution study involved 56 partially used syringes cultured for aerobic bacteria. Only one weakly positive culture was detected among these 56 samples, which prompted us to carry out this expanded study involving multiple centers and different injection techniques. Samples were collected from four centers. Following periurethral injection in an office setting, 166 partially used syringes of glutaraldehyde cross-linked collagen were refrigerated for between 1 and 104 weeks (average 58). Material from all 166 syringes was then cultured qualitatively and quantitatively for both aerobic and anaerobic organisms. Collagen from one syringe grew >100,000 colonies of Escherichia coli. All other cultures were negative. In the pilot study, one culture of 56 syringes was weakly positive for coagulase-negative staphylococcus. When the results from both studies were considered together, only two of 222 partially used syringes (0.9%) were contaminated. The background risk of local infection associated with periurethral collagen injection is approximately 0.29%. Using the statistical equation 'number needed to harm', we found that a clinician would have to reuse 111 syringes at a saving of $34,965 before he or she would cause a single local injection by so doing. Therefore, we feel that it may be cost-effective and safe to reinject material from a partially used syringe of glutaraldehyde cross-linked collagen during a subsequent treatment session on an individual.

Is it safe to reuse a syringe of glutaraldehyde cross-linked collagen? A microbiological study

PURPOSE

We evaluated the safety of saving partially used syringes of glutaraldehyde cross-linked collagen for subsequent treatment sessions in an individual.

MATERIALS AND METHODS

After periurethral injection in an office setting 56 partially used syringes of glutaraldehyde cross-linked collagen were stored in a refrigerator for 1 to 61 weeks (mean 15). Collagen from all 56 syringes was then cultured qualitatively using a broth medium at 35C and semiquantitatively using a chocolate agar plate at 22 to 30C for 5 days each.

RESULTS

A qualitative broth culture was positive for coagulase negative staphylococcus but the results of semiquantitative chocolate agar culture of material from the same syringe were negative. All cultures of the other 55 syringes were negative.

CONCLUSIONS

The positive culture most likely resulted from contamination during periurethral injection or the culturing process. Minimal contamination from and the great potential cost savings of reusing glutaraldehyde cross-linked collagen for subsequent treatments in an individual indicate the need for an expanded study involving multiple centers.

Analysis of the Wilms tumor suppressor gene WT1 in endometrial carcinoma

This study reports on the evaluation of the Wilms tumor suppressor gene WT1 in 14 endometrial carcinomas. Despite the fact that several endometrial carcinomas were shown to express WT1, we were unable to demonstrate mutations in the MT1 zinc finger region, suggesting that WT1 does not play a prominent role in the etiology of this malignancy.

The impact of adjuvant nephrectomy on multimodality treatment of metastatic renal cell carcinoma

Multimodality treatment of metastatic renal cell carcinoma with biological response modifiers and cytoreductive surgery has produced durable responses. The timing and impact of cytoreductive surgery on the success of immunotherapy require further study. We reviewed the treatment of 62 patients with metastatic renal cell carcinoma and primary tumors in place who qualified for multimodality treatment comprising adjuvant nephrectomy and biological response modifier protocols at our institution between 1987 and 1992. Of the patients 37 were scheduled to undergo initial adjuvant nephrectomy followed by biological response modifier therapy. A total of 25 patients underwent initial biological response modifier therapy with planned delayed adjuvant nephrectomy if a response to treatment was demonstrated. Of the 37 patients undergoing initial adjuvant nephrectomy, 8 (22%) were unable to enter induction of immunotherapy because of perioperative complications (1), medical contraindications (2), tumor progression (4) or death (1). Three patients in the initial adjuvant nephrectomy group (8%) had a partial response and the median survival in this group was 12 months (range 1 to 57). In the initial biological response modifier group 3 patients (12%) with an objective response (2 complete and 1 partial) to biological response modifier therapy underwent nephrectomy. The median survival for the initial biological response modifier group was 14 months (range 1 to 48). These results add to our understanding of the impact of adjuvant nephrectomy on patients with metastatic renal cell carcinoma considered for immunotherapy protocols.

Magnetic resonance imaging of pelvic tumors in children

Pelvic tumors in children may be large, complex and of unknown origin. Preoperative radiological information regarding tumor localization and extent becomes essential in these cases for proper staging and surgical planning. Magnetic resonance imaging (MRI) offers the ability to enhance the surgical preparation of children who present with a pelvic mass. Advantages of MRI over computerized tomography include improved soft tissue characterization, signal enhancement of neuroendocrine tumors and multiplanar imaging. These features better define the origin, size and extent of tumors. In addition, no ionizing radiation is required. Several examples of pelvic tumors are presented. The new anatomical information provided by MRI altered surgical planning previously based on computerized tomography findings alone.

Primary testicular and paratesticular tumors of childhood

Testicular and paratesticular neoplasms are uncommon tumors of childhood. Consequently, the experience gained with regard to their optimal management is limited in any given children's cancer centre. Here we review the classification, diagnosis, and staging of testicular and paratesticular neoplasms and subsequently discuss the more frequently occurring ones: germ cell tumors, gonadal stromal tumors, gonadoblastoma, tumors of the supporting tissue, lymphomas and leukemias, tumor-like lesions, secondary tumors, and tumors of the adnexa.

Analysis of WT1 in granulosa cell and other sex cord-stromal tumors

The molecular genetic events involved in the etiology of granulosa cell, Sertoli cell, and Leydig cell tumors are unknown. The expression of the Wilms' tumor suppressor gene WT1 in granulosa and Sertoli cells prompted us to analyze this gene for mutations in 11 granulosa cell tumors, three Leydig cell tumors, and one Sertoli/Leydig cell tumor. Although most of these tumors express WT1 mRNA, none harbors a WT1 mutation in the zinc finger domains where > 90% of WT1 mutations in sporadic Wilms' tumors have been found. In addition we were able to exclude tumor-specific loss of heterozygosity in 13 of 15 cases. Taken together these results suggest that the WT1 gene is unlikely to play an important role in the development of sex cord-stromal tumors.