Evaluation of cryoprobe deployment precision with body surface and in situ templates.

OBJECTIVE: To evaluate the precision of cryoprobe targeting with a surface template, an in situ template (on the target organ), or a combined approach. MATERIALS AND METHODS: Fourteen participants placed five 17 G cryoprobes into porcine kidneys in a laparoscopic trainer using a surface template (group 1), an in situ template (group 2) or a combination of the two templates (group 3). The distance from the ideal probe placement was measured both on the anterior and posterior aspect of the kidney. The sequence of attempts was randomized. The distances were compared across the three groups using anova with the adjustment for multiple comparisons. RESULTS: The mean distance from the ideal probe placement was 1.58 cm (anterior) and 1.81 cm (posterior) in group 1, 0.05 cm and 0.39 cm in group 2, and 0.07 cm and 0.22 cm in group 3, respectively. The placement of the probes was significantly more accurate in groups 2 (P < 0.001 anteriorly and P < 0.002 posteriorly) and 3 (P = 0.001 anteriorly and P < 0.001 posteriorly) compared with group 1. There was no significant difference between groups 2 and 3. CONCLUSION: In this in vitro model, the use of internal or combined internal and external templates allows for significantly more precise deployment of 17-G cryoprobes than a standard external template alone.

Large cell neuroendocrine carcinoma of prostate: a clinicopathologic summary of 7 cases of a rare manifestation of advanced prostate cancer.

Neuroendocrine (NE) differentiation in prostate cancer is typically detected by immunohistochemistry as single cells in conventional adenocarcinoma. Prostatic NE tumors, such as carcinoid or small cell carcinoma, are rare and large cell NE carcinoma (LCNEC) is described only in case reports. We identified 7 cases of LCNEC and compiled their clinicopathologic characteristics. In 6 cases, there was a history of adenocarcinoma treated with hormone therapy for a mean of 2.4 years (range: 2 to 3 y). The remaining case was de novo LCNEC. LCNEC was incidentally diagnosed in palliative transurethral resection specimens in 5 cases. The mean patient age at diagnosis with LCNEC was 67 years (range: 43 to 81 y). LCNEC comprised solid sheets and ribbons of cells with abundant pale to amphophilic cytoplasm, large nuclei with coarse chromatin and prominent nucleoli along with brisk mitotic activity and foci of necrosis. In 6 cases, there were foci of admixed adenocarcinoma, 4 of which showed hormone therapy effects. LCNEC was strongly positive for CD56, CD57, chromogranin A, synaptophysin, and P504S/alpha methylacyl CoA racemase. There was strong bcl-2 overexpression, expression of MIB1, and p53 in >50% of nuclei, focally positive staining for prostate specific antigen and prostatic acid phosphatase and negative androgen receptor staining. Follow-up was available for 6 patients, all of who died with metastatic disease at mean of 7 months (range: 3 to 12 mo) after platinum-based chemotherapy. LCNEC of prostate is a distinct clinicopathologic entity that typically manifests after long-term hormonal therapy for prostatic adenocarcinoma and likely arises through clonal progression under the selection pressure of therapy.

CDKN1A and CDKN1B polymorphisms and risk of advanced prostate carcinoma.

A multigenic model of prostate cancer susceptibility has been proposed, in which common polymorphic variants of genes, such as the androgen and vitamin D receptor, contribute to tumorigenesis. The discovery of additional genetic factors that contribute to prostate cancer risk should provide opportunities for new approaches to the detection and treatment of this common malignancy. Herein, we examined single nucleotide polymorphic variants in the 3'-untranslated region of CDKN1A (p21(cip1)) and in codon 109 of CDKN1B (p27(kip1)) for association with advanced prostate cancer in a European-American population. Ninety-six cases and 106 controls were analyzed using PCR amplification and restriction digestion assays. CDKN1A genotype was scored as CC, CT, and TT on the basis of the digestion products. The CDKN1A genotypes CT and TT were associated with an increased risk of advanced prostate carcinoma compared with the CC genotype [odds ratio (OR), 2.24; 95% confidence interval (CI), 1.02-4.95]. The CDKN1B genotype was scored as VV, VG, or GG, again on the basis of the digestion products. The CDKN1B genotype VV was also associated with an increased risk of advanced prostate carcinoma (OR, 1.95; 95% CI, 1.09-3.47). These associations were particularly strong in those patients with androgen-independent disease [OR = 2.88 (95% CI, 1.19-6.97) and 2.11 (95% CI, 1.05-4.22) for high-risk genotypes of CDKN1A and CDKN1B, respectively]. In addition, the association of CDKN1B was particularly strong in the cohort of patients under the median age of diagnosis (OR, 2.23; 95% CI, 1.08-4.59). These results suggest that in a European-American population, CDKN1A and CDKN1B variants are associated with advanced prostate cancer. Analysis of CDKN1A and/or CDKN1B genotypes may prove useful in determining which patients are at risk for developing advanced prostate carcinoma and therefore would gain the most from aggressive screening, prophylaxis, and/or treatment.

Comparison of running and interrupted vesicourethral anastomoses in a porcine model.

PURPOSE: To compare running and interrupted suturing techniques for porcine vesicourethral anastomosis with regard to procedure time, histopathologic effects, and leakage. MATERIALS AND METHODS: Twelve domestic pigs were randomized to a running (N = 6) or an interrupted (N = 6) vesicourethral anastomosis with polyglycolic acid sutures. In each case, the bladder was drained for 7 days. A cystogram was performed immediately after completion of each anastomosis and on postoperative days 7 and 30. Animals were sacrificed on postoperative day 30, and the area of the anastomosis was excised en bloc for histopathologic evaluation. RESULTS: All procedures were completed laparoscopically. The mean operative time for continuous and interrupted suturing were 27.5 and 36.8 minutes, respectively (P = 0.3324). A significant learning curve was noted for both anastomoses, with operative times decreasing with experience in both groups. There was no difference in anastomotic leakage. Histopathology examination revealed more muscle-layer fibrosis in the interrupted- suture group than in the continuous-suture group, with a mean score of 2.17 and 1.67, respectively (P = 0.0325). CONCLUSIONS: Both continuous and interrupted vesicourethral anastomoses are feasible. In this in-vivo porcine comparison, there was no difference with respect to procedure time or anastomotic leakage. However, histopathologic grading demonstrated greater muscle fibrosis in the interrupted-suture group.

Is there a better way to biopsy the prostate? Prospects for a novel transrectal systematic biopsy approach.

The study reported here was undertaken to investigate a novel method of systematic, 3-dimensional, template-guided, transrectal ultrasound-guided prostate biopsy. The TargetScan transrectal ultrasound and prostatic biopsy system (Envisioneering Medical Technologies, St. Louis, MO) uses a stationary transrectal ultrasound probe that acquires 3-dimensional and simultaneous biplanar ultrasound imaging. With the use of prostate-specific measurements, targeted transrectal biopsy specimens of the prostate are taken. The precise location of each specimen is defined by 2 coordinates: depth in centimeters proximal from the apex of the prostate, and degree of rotation (clockwise or counterclockwise from 12 o'clock). This device has been evaluated when used with radical prostatectomy specimens. Studies on 20 radical prostatectomy specimens disclosed that simulated TargetScan biopsy correctly identified cancer in 16 (80%) prostates and high-grade prostatic intraepithelial neoplasia in 2 others. Simulated TargetScan biopsy correctly characterized 88% of prostatic octants in terms of whether or not they harbored cancer. This technique was reproducible from operator to operator, and 85% biopsy core concordance was attained when the TargetScan protocol was simulated in 2 urology residents. The TargetScan biopsy system seems to be an effective transrectal alternative to transperineal, 3-dimensional, ultrasound-guided biopsies. Its reproducibility from operator to operator suggests that it may be useful for guiding rebiopsy of specific locations within the prostate and for providing targeted focal prostate cancer therapy.

Prospective randomized comparison of laparoscopic and hand-assisted laparoscopic radical nephrectomy.

OBJECTIVES: The majority of localized renal cancers are currently managed by laparoscopic radical nephrectomy, with or without the hand-assist device. In this prospective randomized study, we evaluated the patient outcomes with a standard laparoscopic radical nephrectomy (LRN) versus a hand-assisted laparoscopic radical nephrectomy (HALN). METHODS: Over a 3-year period, we randomly assigned 21 patients with a localized renal mass of 10 cm or larger to a LRN group with intact specimen extraction or a HALN. The trocar size and sites, the position of the hand-assist device, and the specimen extraction sites were standardized. Patient characteristics, surgical complications, postoperative pain, and convalescence were evaluated. RESULTS: Twelve patients underwent LRN and 9 patients underwent HALN. Both groups had similar body mass indices (BMI), mean tumor diameter (LRN, 5.8 cm; HALN, 5.6 cm), and American Society of Anesthesiologists (ASA) scores. The HALN cohort was significantly older (mean age = 68 years) than the LRN cohort (mean age = 54 years) (P = 0.019). Perioperatively, both groups had similar mean times to oral intake and discharge (LRN 2.6 days and HALN 3 days, P = 0.6). Although both groups reported similar postoperative pain scale scores on day 1, at 1 and 3 months. Two patients in each group had complications (LRN 16% and HALN 22%). CONCLUSIONS: In comparing HALN and LRN, there was no difference in the majority of operative and postoperative parameters, including hospital stay and postoperative pain. However, LRN patients had a significantly shorter convalescence with quicker return to normal activities and work than the HALN group. Part of the delay in long-term convalescence parameters may be due to the older patients in the HALN cohort.

Trends in nephron-sparing surgery for renal neoplasia.

OBJECTIVES: To determine the extent that laparoscopy has replaced open surgery for nephron-sparing surgery in a mature laparoscopic environment. METHODS: The records of all patients at Washington University who underwent nephron-sparing surgery for localized renal masses from 1999 to 2003 were examined for clinical and pathologic information. Information regarding the mass size, surgery type performed, and surgeon training was obtained. RESULTS: A total of 271 patients underwent nephron-sparing surgery from January 1999 to December 2003. During the study period, the total number of partial nephrectomies increased from 33 per year to 91 per year. The proportion of laparoscopic partial nephrectomy increased from 3% of total cases to 56% of total cases. Open partial nephrectomy decreased from 97% of cases to 24% of cases; however, the absolute number of open partial nephrectomies only decreased from 32 to 22 per year. Laparoscopic cryoablation increased from 0% of cases to 20% of cases. Endourologists increased their frequency of performing open partial nephrectomy, and oncologists increased their frequency of performing laparoscopic renal surgery. CONCLUSIONS: Laparoscopic nephron-sparing surgery has not completely replaced open partial nephrectomy for low-stage renal neoplasia; however, the number of laparoscopic partial nephrectomies has increased rapidly in recent years. Laparoscopic approaches are being performed by all urologists treating renal malignancies at our institution and this reflects changes in the surgical treatment of renal cancer.

Extrarenal vascular anatomy of kidney: assessment of variations and their relevance to partial nephrectomy.

OBJECTIVES: To evaluate the feasibility of selective segmental artery clamping during partial nephrectomy. METHODS: Precise extraparenchymal renal hilar dissection was performed on 73 fixed cadaveric kidneys. The surgical accessibility to clamping of each presegmental and segmental artery from the anterior and posterior approaches was determined on the basis of vessel length, position within the renal hilum, and degree of overlying collecting system or venous structures. RESULTS: The vascular anatomy consisted of zero, one, or two presegmental arteries (extrarenal main renal artery branches that split into two or more segmental arteries) in 49.3%, 31.5%, and 19.2% of the kidneys, respectively. From a posterior approach, the posterior segmental artery was accessible to isolated clamping in 81.8% of the kidneys (segmental accessibility rate) and was accessible to clamping at the presegmental level in 12.7% (presegmental accessibility rate) for a total accessibility rate of 90.9%. The total accessibility rate for the inferior segmental artery was 88.5% from an anterior and 66.7% from a posterior surgical approach. The apical artery total accessibility rate was 72.3% and 40.5% from an anterior and posterior approach, respectively. The corresponding middle and superior segmental artery total accessibility rates were 50.8% and 32.8%. CONCLUSIONS: In this cadaveric model, hilar dissection and clamping of the renal segmental arteries is anatomically feasible in most cases. Posterior and polar tumors will likely be more amenable to segmental vascular control. Selective segmental vascular control may offer the benefits of total hilar control while reducing overall renal ischemic injury.

Parenchymal imaging adds diagnostic utility in evaluating haematuria.

OBJECTIVE: To compare the findings of renal ultrasonography (US) in the evaluation of patients with and with no haematuria. The increased use of cross-sectional imaging and US has led to a dramatic improvement in the diagnosis of renal masses, such that computed tomography and/or US have been integrated into the diagnostic evaluation of haematuria, and many more incidental renal lesions are now detected. Thus it is possible that the lesions identified during evaluation for haematuria are incidental, i.e. identified serendipitously, and unrelated to the haematuria. PATIENTS AND METHODS: We retrospectively compared the US findings obtained from 301 patients referred for new-onset haematuria to those obtained from 600 patients being evaluated for other than urological reasons. All imaging and patient charts were reviewed to verify the clinical and radiological data. RESULTS: Haematuria was associated with all renal abnormalities, with an odds ratio (OR, 95% confidence interval) of 4.7 (3.6-7.3). Importantly, haematuria was associated with a renal mass, with an OR of 6.7 (2.8-16.3). Subset analysis revealed that patients with macroscopic and microscopic haematuria had significantly more renal abnormalities (OR 4.7, 2.7-8.2, and 5.3, 3.2-8.8, respectively) and renal masses (OR 7.3, 2.7-20.3, and 6.5, 2.3-18.6, respectively) than controls. CONCLUSIONS: Both macroscopic and microscopic haematuria are associated with a greater risk of identifying renal lesions. This supports the conclusion that the renal lesions identified with modern imaging techniques during the evaluation of both microscopic and macroscopic haematuria are not serendipitous.

Development of exophytic tumor model for laparoscopic partial nephrectomy: technique and initial experience.

OBJECTIVES: To develop and test a porcine model to help teach the techniques needed to perform laparoscopic partial nephrectomy (LPN), which is a technically challenging procedure with necessary reconstructive skills that are difficult to transfer. METHODS: A tumor model was created by unilateral subcapsular percutaneous injection of liquid plastic (Smooth-Cast 320) in five pig kidneys. Five Washington University urologists performed LPN and assessed the efficacy of the tumor model. Subsequently, the tumor model was evaluated as a tool for teaching LPN during the Washington University Advanced Laparoscopic and Robotic Urologic Oncology Course. Twenty-eight participants performed unilateral porcine LPN with the tumor model. Questionnaires were used to assess the utility of this tumor model. RESULTS: Unilateral tumors were successfully created in five pigs and remained intact during all LPN procedures. Visually, the tumors appeared as white exophytic masses. Ultrasonography revealed a well-circumscribed, hypoechoic lesion and a mean diameter of 2.02 cm. The mean operative time was 32.4 minutes. In subsequent testing, 24 (86%) of the 28 participants returned the questionnaire, and 96% responded that the tumor model had enhanced their LPN learning experience. Seven course participants (29%) reported problems with hemostasis, ultrasonography, or laparoscopic instrumentation. Two tumor model-related complications occurred. During the initial evaluation, one pig experienced a fatal pulmonary embolism of the plastic. During the course, a second animal experienced extravasation of the solution into the renal collecting system. CONCLUSIONS: For surgical education purposes, the Smooth-Cast model is an effective surgical tool for LPN. Most of the surgeons in this evaluation believed the model enhanced their learning experience.

Does varicocele grade predict vein number and size at microsurgical subinguinal repair?

OBJECTIVES: To correlate the varicocele grade on physical examination with the number and size of the veins present and ligated during surgery. Varicoceles are correctable causes of male factor infertility. No prior anatomic studies have correlated the preoperative clinical grade of a varicocele with the number of veins discovered and ligated during microsurgical subinguinal repair. METHODS: A total of 65 consecutive men (mean age 33.8 years) diagnosed during office evaluation with either unilateral left varicocele or bilateral varicoceles underwent microsurgical subinguinal varicocelectomy by one urologist. At surgery, the number and size (small, less than 1.0 mm; medium, 1.0 mm or greater to less than 4.0 mm; large, 4.0 mm or greater) of the spermatic cord veins present and ligated were recorded. These findings were correlated with the size of the preoperative varicocele grade. RESULTS: Of the 71 varicocele units, 65 qualified for analysis. Of the patients with a grade 1 varicocele, a mean (+/-SD) of 2.4 (+/-2.5) small veins, 4.7 (+/-2.1) medium veins, 0.3 (+/-0.58) large veins, and 7.5 (+/-3.0) total veins were ligated. Of patients with a grade 2 varicocele, a mean of 2.6 (+/-2.3) small veins, 5.3 (+/-3.1) medium veins, 0.47 (+/-0.78) large veins, and 8.3 (+/-3.2) total veins were ligated. Of patients with grade 3 varicoceles, a mean of 1.8 (+/-1.8) small veins, 4.6 (+/-2.3) medium veins, 1.0 (+/-0.75) large veins, and 6.9 (+/-2.6) total veins were ligated. Using analysis of variance, the grade 3 varicoceles had significantly more large veins than did grade 1 varicoceles (P <0.05). CONCLUSIONS: Grade 3 varicoceles have a greater number of large veins compared with grade 1 varicoceles.