Gerald Tan

Clinical and pathologic predictors of Gleason sum upgrading in patients after radical prostatectomy: Results from a single institution series

OBJECTIVES Preoperative Gleason scores (GSs) are often upgraded after pathologic examination of the prostate following radical prostatectomy (RP). There have been disparate reports of the impact of different factors as predictors of GS upgrading after RP. We sought to study the robustness of frequently reported predictors in an unselected single institution cohort. PATIENTS AND METHODS A total of 684 patients with biopsy-proven prostate cancer treated with RP between 2004 and 2007 were included in the study. The association between clinical and pathologic parameters and GS upgrading was retrospectively evaluated. Logistic regression analysis was used to identify predictors of pathologic grading changes. Likelihood of upgrading was compared between tertile groups for prostate volume and prostate-specific antigen (PSA) density using χ(2) analysis and multivariate logistic regression. Pathologic outcomes were compared between cases with and without GS upgrading. RESULTS The overall mean age was 64.3 years, with median PSA level of 7.04 ng/ml. Overall, 203 cases (29.7%) were upgraded, whereas 481 patients (70.3%) were downgraded or had identical biopsy and pathologic GS after RP. Patients with prostate volume of <31 g were upgraded in 32.6% of the cases compared with 21.9% in patients with prostate volume of >45 g (P = 0.020). On multivariate analysis preoperative PSA (P < 0.0001), prostate volume (P < 0.0001), and PSA density (P < 0.0001) were predictive of Gleason sum upgrading. Upgraded patients were more likely to have extracapsular extension, seminal vesicle invasion, positive surgical margins, and lymphonodular invasion at RP (P < 0.001, P < 0.001, P < 0.001, and P < 0.001, respectively). CONCLUSIONS Smaller prostate volume and higher PSA level are associated with clinically significant upgrading of GS. PSA density as a function of both is a significant predictor of GS upgrading in low- and high-risk patients. This may be of relevance in the pretreatment risk assessment of prostate cancer patients.

Multiphoton microscopy of prostate and periprostatic neural tissue: a promising imaging technique for improving nerve-sparing prostatectomy.

BACKGROUND AND PURPOSE Various imaging modalities are under investigation for real-time tissue imaging of periprostatic nerves with the idea of improving the results of nerve-sparing radical prostatectomy. We explored multiphoton microscopy (MPM) for real-time tissue imaging of the prostate and periprostatic neural tissue in a male Sprague-Dawley rat model. The unique advantage of this technique is the acquisition of high-resolution images without necessitating any extrinsic labeling agent and with minimal phototoxic effect on tissue. MATERIALS AND METHODS The prostate and cavernous nerves were surgically excised from male Sprague-Dawley rats. The imaging was carried out using intrinsic fluorescence and scattering properties of the tissues without any exogenous dye or contrast agent. A custom-built MPM, consisting of an Olympus BX61WI upright frame and a modified MRC 1024 scanhead, was used. A femtosecond pulsed titanium/sapphire laser at 780-nm wavelength was used to excite the tissue; laser power under the objective was modulated via a Pockels cell. Second harmonic generation (SHG) signals were collected at 390 (+/-35 nm), and broadband autofluorescence was collected at 380 to 530 nm. The images obtained from SHG and from tissue fluorescence were then merged and color coded during postprocessing for better appreciation of details. The corresponding tissues were subjected to hematoxylin and eosin staining for histologic confirmation of the structures. RESULTS High-resolution images of the prostate capsule, underlying acini, and individual cells outlining the glands were obtained at varying magnifications. MPM images of adipose tissue and the neural tissues were also obtained. Histologic confirmation and correlation of the prostate gland, fat, cavernous nerve, and major pelvic ganglion validated the findings of MPM. CONCLUSION Real-time imaging and microscopic resolution of prostate and periprostatic neural tissue using MPM is feasible without the need for any extrinsic labeling agents. Integration of this imaging modality with operative technique has the potential to improve the precision of nerve-sparing prostatectomy.

Technological Advances in Robotic-Assisted Laparoscopic Surgery

In this article, the authors describe the evolution of urologic robotic systems and the current state-of-the-art features and existing limitations of the da Vinci S HD System (Intuitive Surgical, Inc.). They then review promising innovations in scaling down the footprint of robotic platforms, the early experience with mobile miniaturized in vivo robots, advances in endoscopic navigation systems using augmented reality technologies and tracking devices, the emergence of technologies for robotic natural orifice transluminal endoscopic surgery and single-port surgery, advances in flexible robotics and haptics, the development of new virtual reality simulator training platforms compatible with the existing da Vinci system, and recent experiences with remote robotic surgery and telestration.

Optimizing Vesicourethral Anastomosis Healing After Robot-Assisted Laparoscopic Radical Prostatectomy: Lessons Learned from Three Techniques in 1900 Patients

BACKGROUND AND PURPOSE Creation of an optimally apposed, tension-free, well-supported vesicourethral anastomosis remains the cornerstone for anastomotic healing after radical prostatectomy. We report the effect of three techniques of bladder neck reconstruction during robot-assisted radical prostatectomy on anastomotic leak, stricture formation, and continence recovery. PATIENTS AND METHODS Between January 2005 to September 2009, 1900 consecutive patients underwent robotic-assisted laparoscopic prostatectomy (RALP) by a single surgeon. Of these, the first 214 underwent vesicourethral conventional anastomosis (CA); the next 303 men underwent anterior reconstruction (AR) only; and last 1383 men underwent total anatomic restoration (TR). Data elements included patient age, body mass index, preoperative biopsy Gleason score and prostate-specific antigen level, prostate volume, total operative time, console time, time for performing vesicourethral anastomosis, estimated blood loss, tumor stage, and margin status on final pathologic findings. Primary end points were rates of clinically significant anastomotic leaks, bladder neck contractures, and time to return of continence. Chi-square and Fisher exact tests were used for analysis of categoric variables. The Cox proportional hazard model was used for both univariate and multivariate analysis. RESULTS Clinically significant anastomotic leakage and bladder neck strictures were significantly fewer in the reconstructed groups (2.3% vs 1.0% vs 0.3% and 3.7% vs 1.3% vs 0.5% in the CA, AR, and TR groups, P < 0.01). Continence rates at 1, 6, 12, 26, and 52 weeks after RALP were also significantly better at all time points with AR and TR compared with CA alone (P < 0.001). CONCLUSIONS TR of the continence mechanism optimizes vesicourethral anastomosis healing and hastens early continence return after RALP.

Robot-assisted laparoscopic radical prostatectomy in the renal allograft transplant recipient.

BACKGROUND AND PURPOSE Since the advent of immunosuppressive therapy, patients have been able to lead longer lives as transplant recipients. We report the first case of robot-assisted laparoscopic prostatectomy in the renal allograft recipient. PATIENTS AND METHODS A 54-year-old man presented with Gleason 3+3 localized prostate cancer with a prostatespecific antigen level of 8.5 ng/mL. He had a history of end-stage renal failure secondary to fulminant acute pyelonephritis necessitating bilateral nephrectomy. Renal allograft transplant in the right iliac fossa was performed in 1981, with adequate renal function while continuing his immunosuppressant regime. The patient also had previous left inguinal herniorrhaphy. Modifications to our surgical approach include placement of a bariatric port superiolaterally to the standard port site; siting the left port inferiolaterally to provide adequate access for pelvic lymph node dissection; and developing the retropubic space largely from the contralateral side to avoid allograft injury. Extensive adhesiolysis was also needed. After negative urethral margin reported on frozen section, vesicourethral anastomosis was fashioned using our Cornell bladder neck anatomic reconstruction technique. RESULTS The patient needed a postoperative transfusion of 1 unit of blood and was discharged on postoperative day 2 after recommencement of immunosuppression. The final pathology report revealed pT(2c) Gleason 7 (3+4) disease and negative surgical margins. Continence was recovered within the first week of catheter removal, and erections sufficient for penetration occurred before 6-week follow-up in the clinic. CONCLUSION Robot-assisted radical prostatectomy is feasible in the carefully selected renal allograft recipient with favorable oncologic, continence, and potency outcomes.

Residency Training Program Paradigms for Teaching Robotic Surgical Skills to Urology Residents

The advent of laparoscopic and robotic techniques for management of urologic malignancies marked the beginning of an ever-expanding array of minimally invasive options available to cancer patients. With the popularity of these treatment modalities, there is a growing need for trained surgical oncologists who not only have a deep understanding of the disease process and adept surgical skills, but also show technical mastery in operating the equipment used to perform these techniques. Establishing a robotic prostatectomy program is a tremendous undertaking for any institution, as it involves a huge cost, especially in the purchasing and maintenance of the robot. Residency programs often face many challenges when trying to establish a balance between costs associated with robotic surgery and training of the urology residents, while maintaining an acceptable operative time. Herein we describe residency training program paradigms for teaching robotic surgical skills to urology residents. Our proposed paradigm outlines the approach to compensate for the cost involved in robotic training establishment without compromising the quality of education provided. With the potential advantages for both patients and surgeons, we contemplate that robotic-assisted surgery may become an integral component of residency training programs in the future.

LAPARO-ENDOSCOPIC SINGLE-SITE SURGERY IN UROLOGY: IS ROBOTICS THE MISSING LINK?

Laparoscopic surgery has dramatically changed the landscape of operative urology, becoming the approach of first choice amongst surgeons and their patients, for its validated benefits of shorter hospitalization, less postoperative pain and earlier recovery. Recently there has been immense interest in both laparo-endoscopic single-site surgery (LESS) and natural orifice transluminal endoscopic surgery (NOTES) approaches to minimally invasive urological surgery. Since Rané et al. [1,2] and Raman et al. [3] performed the world’s first human LESS nephrectomies in 2007, there have been several presentations and reports validating the feasibility and reproducibility of LESS procedures in urology, most notably led by investigators from the Cleveland Clinic [4]. From these early experiences, it would appear that most extirpative and reconstructive urological procedures performed through conventional multiport laparoscopy can be reproduced via a LESS approach. The single undisputed benefit of LESS is improved cosmesis, constraining trocars or the singleaccess port to the peri-umbilical site. Whilst Gill et al. [5] reported less postoperative pain and discomfort in patients undergoing donor nephrectomy via the single-port laparoscopic approach, Raman et al. [6] found no significant difference between single-port and conventional multiport laparoscopic nephrectomy in terms of operative time, mean blood loss, hospital stay or postoperative analgesic requirements.

Neuroanatomic basis for traction-free preservation of the neural hammock during athermal robotic radical prostatectomy.

Purpose of review Much of the progress achieved in the past two decades in improving potency outcomes after radical prostatectomy has resulted from an improved appreciation of the anatomic basis of the nerves responsible for erection. We review the current literature evaluating the neuroanatomy of prostate and operative strategies for better preservation of sexual function. Recent findings Recent studies suggest an alternative and more complex course of nerves than previously described. Periprostatic nerves can be divided into three broad surgically identifiable zones: the proximal neurovascular plate, the predominant neurovascular bundle, and the accessory neural pathways. Better appreciation of the variable and often invisible anatomical course of the cavernosal nerves continues to engender innovations in surgical technique to optimize their preservation. Summary Improved anatomic understanding has optimized surgical technique in order to improve potency outcomes following radical prostatectomy.

Anatomic Restoration Technique: A Biomechanics-based Approach for Early Continence Recovery After Minimally Invasive Radical Prostatectomy

Despite refinements in surgical technique over the past decade, urinary incontinence following radical prostatectomy remains a frustrating and costly side effect that significantly impairs patients’ quality of life. With the increasing popularity of radical prostatectomy as a firstline treatment for early prostate cancer, and with more patients being diagnosed and treated at a younger age, post prostatectomy incontinence remains a significant issue. Reported risk factors include increasing patient age, bladder dysfunction before surgery, previous transurethral resection of the prostate for obstructive symptoms, anastomotic stricture, surgical technique, and surgeon experience. 1,2 Beginning in 2006, our group has made stepwise progress in overcoming this problem through technical innovations borne from study of real-time intraoperative video and cadaveric anatomy, histopathologic analysis of final prostatectomy specimens, and data analysis of functional outcomes. 3-7 We have developed a paradigm of 7 key principles based on possible biomechanical forces acting on the urethral rhabdosphincter and newly fashioned anastomosis that we believe will hasten early con

Scientific and technical advances in continence recovery following radical prostatectomy

The advent of prostate-specific antigen screening has changed the global epidemiology of prostate cancer, with men being diagnosed with organ-confined cancer at a younger age. Radical prostatectomy with curative intent for these patients, while delivering excellent long-term survival outcomes, still has significant side effects, chiefly postprostatectomy incontinence. Increasing age, shorter pre- and post-operative membranous urethral length, anastomotic strictures, obesity, low surgeon volume, variations of surgical technique and previous prostate surgery have been reported as negative risk factors for delayed continence recovery and/or permanent incontinence following radical prostatectomy. Significant progress in elucidating the functional anatomy and physiology of the male continence mechanism from cadaveric and videourodynamic studies have enabled surgeons to propose innovative surgical techniques during radical prostatectomy for augmenting continence preservation and early return. These have included optimizing the preservation of urethral rhabdosphincter length; avoiding rhabdosphincter injury; posterior reconstruction of Denonvilliers’ musculofascial plate; preservation of the bladder neck and internal sphincter; bladder neck intussusception; bladder neck mucosal eversion; preservation of the puboprostatic ligaments and arcus tendineus; and preservation of putative nerves supplying the continence mechanism. We review the scientific and technical advances in continence recovery following radical prostatectomy, identify the key principles undergirding early return of continence, highlight various treatment strategies for early and refractory postprostatectomy incontinence and describe our experience with a paradigm of these unified key principles. Increasing application of these principles in computer-aided (robotic), minimally invasive and minimal-access (i.e., single-port or natural orifice transluminal) approaches will hopefully enable patients to derive maximal benefit from curative prostatectomy while experiencing early return of continence in the not too distant future.