Andrew J. Hung

“Trifecta” in Partial Nephrectomy

PURPOSE We introduce the concept of trifecta outcomes during robotic/laparoscopic partial nephrectomy, in which the 3 key outcomes of negative cancer margin, minimal renal functional decrease and no urological complications are simultaneously realized. We report serial trifecta outcomes in patients treated with robotic/laparoscopic partial nephrectomy for tumor in a 12-year period. MATERIALS AND METHODS A total of 534 patients had complete data available and were retrospectively divided into 4 chronologic eras, including the discovery era--139 from September 1999 to December 2003, conventional hilar clamping era--213 from January 2004 to December 2006, early unclamping era--104 from January 2007 to November 2008 and anatomical zero ischemia era--78 from March 2010 to October 2011. Renal functional decrease was defined as a greater than 10% reduction in the actual vs volume predicted postoperative estimated glomerular filtration rate. RESULTS Across the 4 eras tumors trended toward larger size (2.9, 2.8, 3.1 and 3.3 cm, p = 0.08) and yet the estimated percent of kidney preserved was similar (89%, 90%, 90% and 88%, respectively, p = 0.3). Recent eras had increasingly complex tumors that were more often 4 cm or greater (p = 0.03), centrally located (p <0.009) or hilar (p <0.0001). Nevertheless, with significant technical refinement warm ischemia time decreased serially (36, 32, 15 and 0 minutes, respectively, p <0.0001). Renal functional outcomes were superior in recent eras with fewer patients experiencing a decrease (p <0.0001). Uniquely, actual estimated glomerular filtration rate outcomes exceeded volume predicted estimated glomerular filtration rate outcomes only in the zero ischemia cohort in regard to other eras (-9.5%, -11%, -0.9% and 4.2%, respectively, p <0.001). Positive cancer margins were uniformly low at less than 1%. Urological complications trended lower in recent eras (p = 0.01). Trifecta outcomes occurred more commonly in recent eras (45%, 44%, 62% and 68%, respectively, p = 0.0002). CONCLUSIONS Trifecta should be a routine goal during partial nephrectomy. Despite increasing tumor complexity, trifecta outcomes of robotic/laparoscopic partial nephrectomy improved significantly in the last decade.

Focal cryotherapy for clinically unilateral, low-intermediate risk prostate cancer in 73 men with a median follow-up of 3.7 years.

BACKGROUND Evolution of cryotherapy for prostate cancer is likely to result in parenchyma-sparing modifications adjacent to the urethra and neurovascular bundle. Results of initial series of focal therapy to minimize cryosurgery-related morbidity without compromising oncologic control have been encouraging, but limited in short-term outcomes. OBJECTIVE To retrospectively report (1) median 3.7-yr follow-up experience of primary focal cryotherapy for clinically unilateral prostate cancer with oncologic and functional outcomes, and (2) matched-pair analysis with contemporaneous patients undergoing radical prostatectomy (RP). DESIGN, SETTING, AND PARTICIPANTS Over 8.5 yr (September 2002 to March 2011), focal cryoablation (defined as ablation of one lobe) was performed in 73 carefully selected patients with biopsy-proven, clinically unilateral, low-intermediate risk prostate cancer. All patients underwent transrectal ultrasound (TRUS) and Doppler-guided sextant and targeted biopsies at entry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Post-therapy follow-up included measuring prostate-specific antigen (PSA) level every 3-6 mo; TRUS biopsies at 6-12 mo and yearly, as indicated; and validated symptom questionnaires. Matched-pair analysis compared oncologic outcomes of focal cryotherapy and RP (matched for age, PSA, clinical stage, and biopsy Gleason score). RESULTS AND LIMITATIONS Complete follow-up was available in 70 patients (median follow-up: 3.7 yr; range: 1-8.5 yr). No patient died or developed metastases. Precryotherapy mean PSA was 5.9 ng/ml and Gleason score was 6 (n=30) or 7 (n=43). Postcryotherapy mean PSA was 1.6 ng/ml (70% reduction compared to precryotherapy; p<0.001). Of 48 patients undergoing postcryotherapy biopsy, 36 (75%) had negative biopsies; positive biopsy for cancer (n=12) occurred in the untreated contralateral (n=11) or treated ipsilateral lobe (n=1). Complete continence (no pads) and potency sufficient for intercourse were documented in 100% and 86% of patients, respectively. Matched-pair comparison of focal cryotherapy and RP revealed similar oncologic outcome, defined as needing salvage treatment. CONCLUSIONS Primary focal cryoablation for low-intermediate risk unilateral cancer affords encouraging oncologic and functional outcomes over a median 3.7-yr follow-up. Close surveillance with follow-up whole-gland biopsies is mandatory.

Face, Content and Construct Validity of a Novel Robotic Surgery Simulator

PURPOSE We evaluated the face, content and construct validity of the novel da Vinci® Skills Simulator™ using the da Vinci Si™ Surgeon Console as the surgeon interface. MATERIALS AND METHODS We evaluated a novel robotic surgical simulator for robotic surgery using the da Vinci Si Surgeon Console and Mimic™ virtual reality. Subjects were categorized as novice-no surgical training, intermediate-surgical training with fewer than 100 robotic cases or expert-100 or more primary surgeon robotic cases. Each participant completed 10 virtual reality exercises with 3 repetitions and a questionnaire with a 1 to 10 visual analog scale to assess simulator realism (face validity) and training usefulness (content validity). The simulator recorded performance based on specific metrics. The performance of experts, intermediates and novices was compared (construct validity) using the Kruskal-Wallis test. RESULTS We studied 16 novices, 32 intermediates with a median surgical experience of 6 years (range 1 to 37) and a median of 0 robotic cases (range 0 to 50), and 15 experts with a median of 315 robotic cases (range 100 to 800). Participants rated the virtual reality and console experience as very realistic (median visual analog scale score 8/10) while expert surgeons rated the simulator as a very useful training tool for residents (10/10) and fellows (9/10). Experts outperformed intermediates and novices in almost all metrics (median overall score 88.3% vs 75.6% and 62.1%, respectively, between group p<0.001). CONCLUSIONS We confirmed the face, content and construct validity of a novel robotic skill simulator that uses the da Vinci Si Surgeon Console. Although it is currently limited to basic skill training, this device is likely to influence robotic surgical training across specialties.

Anatomic renal artery branch microdissection to facilitate zero-ischemia partial nephrectomy.

BACKGROUND Robot-assisted and laparoscopic partial nephrectomies (PNs) for medial tumors are technically challenging even with the hilum clamped and, until now, were impossible to perform with the hilum unclamped. OBJECTIVE Evaluate whether targeted vascular microdissection (VMD) of renal artery branches allows zero-ischemia PN to be performed even for challenging medial tumors. DESIGN, SETTING, AND PARTICIPANTS A prospective cohort evaluation of 44 patients with renal masses who underwent robot-assisted or laparoscopic zero-ischemia PN either with anatomic VMD (group 1; n=22) or without anatomic VMD (group 2; n=22) performed by a single surgeon from April 2010 to January 2011. INTERVENTION Zero-ischemia PN with VMD incorporates four maneuvers: (1) preoperative computed tomographic reconstruction of renal arterial branch anatomy, (2) anatomic dissection of targeted, tumor-specific tertiary or higher-order renal arterial branches, (3) neurosurgical aneurysm microsurgical bulldog clamp(s) for superselective tumor devascularization, and (4) transient, controlled reduction of blood pressure, if necessary. MEASUREMENTS Baseline, perioperative, and postoperative data were collected prospectively. RESULTS AND LIMITATIONS Group 1 tumors were larger (4.3 vs 2.6 cm; p=0.011), were more often hilar (41% vs 9%; p=0.09), were medial (59% and 23%; p=0.017), were closer to the hilum (1.46 vs 3.26 cm; p=0.0002), and had a lower C index score (2.1 vs 3.9; p=0.004) and higher RENAL nephrometry scores (7.7 vs 6.2; p=0.013). Despite greater complexity, no group 1 tumor required hilar clamping, and perioperative outcomes were similar to those of group 2: operating room time (4.7 and 4.1h), median blood loss (200 and 100ml), surgical margins for cancer (all negative), major complications (0% and 9%), and minor complications (18% and 14%). The median serum creatinine level was similar 2 mo postoperatively (1.2 and 1.3mg/dl). The study was limited by the relatively small sample size. CONCLUSIONS Anatomic targeted dissection and superselective control of tumor-specific renal arterial branches facilitate zero-ischemia PN. Even challenging medial and hilar tumors can be excised without hilar clamping. Global surgical renal ischemia has been eliminated for most patients undergoing PN at our institution.

Concurrent and Predictive Validation of a Novel Robotic Surgery Simulator: A Prospective, Randomized Study

PURPOSE We evaluated the concurrent and predictive validity of a novel robotic surgery simulator in a prospective, randomized study. MATERIALS AND METHODS A total of 24 robotic surgery trainees performed virtual reality exercises on the da Vinci® Skills Simulator using the da Vinci Si™ surgeon console. Baseline simulator performance was captured. Baseline live robotic performance on ex vivo animal tissue exercises was evaluated by 3 expert robotic surgeons using validated laparoscopic assessment metrics. Trainees were then randomized to group 1-simulator training and group 2-no training while matched for baseline tissue scores. Group 1 trainees underwent a 10-week simulator curriculum. Repeat tissue exercises were done at study conclusion to assess performance improvement. Spearmans analysis was used to correlate baseline simulator performance with baseline ex vivo tissue performance (concurrent validity) and final tissue performance (predictive validity). The Kruskal-Wallis test was used to compare group performance. RESULTS Groups 1 and 2 were comparable in pre-study surgical experience and had similar baseline scores on simulator and tissue exercises (p >0.05). Overall baseline simulator performance significantly correlated with baseline and final tissue performance (concurrent and predictive validity each r = 0.7, p <0.0001). Simulator training significantly improved tissue performance on key metrics for group 1 subjects with lower baseline tissue scores (below the 50th percentile) than their group 2 counterparts (p <0.05). Group 1 tended to outperform group 2 on final tissue performance, although the difference was not significant (p >0.05). CONCLUSIONS Our study documents the concurrent and predictive validity of the Skills Simulator. The benefit of simulator training appears to be most substantial for trainees with low baseline robotic skills.

Comparative assessment of three standardized robotic surgery training methods

To evaluate three standardized robotic surgery training methods, inanimate, virtual reality and in vivo, for their construct validity. To explore the concept of cross‐method validity, where the relative performance of each method is compared.

Predictive Value of Magnetic Resonance Imaging Determined Tumor Contact Length for Extracapsular Extension of Prostate Cancer

PURPOSE Tumor contact length is defined as the amount of prostate cancer in contact with the prostatic capsule. We evaluated the ability of magnetic resonance imaging determined tumor contact length to predict microscopic extracapsular extension compared to existing predictors of extracapsular extension. MATERIALS AND METHODS We retrospectively analyzed the records of 111 consecutive patients with magnetic resonance imaging/ultrasound fusion targeted, biopsy proven prostate cancer who underwent radical prostatectomy from January 2010 to July 2013. Median patient age was 64 years and median prostate specific antigen was 8.9 ng/ml. Clinical stage was cT1 in 93 cases (84%) and cT2 in 18 (16%). Postoperative pathological analysis confirmed pT2 in 71 patients (64%) and pT3 in 40 (36%). We evaluated 1) in the radical prostatectomy specimen the correlation of microscopic extracapsular extension with pathological cancer volume, pathological tumor contact length and Gleason score, 2) the correlation between microscopic extracapsular extension and magnetic resonance imaging tumor contact length, and 3) the ability of preoperative variables to predict microscopic extracapsular extension. RESULTS Logistic regression analysis revealed that pathological tumor contact length correlated better with microscopic extracapsular extension than the predictive power of pathological cancer volume (0.821 vs 0.685). The Spearman correlation between pathological and magnetic resonance imaging tumor contact length was r = 0.839 (p <0.0001). ROC AUC analysis revealed that magnetic resonance imaging tumor contact length outperformed cancer core involvement on targeted biopsy and the Partin tables to predict microscopic extracapsular extension (0.88 vs 0.70 and 0.63, respectively). At a magnetic resonance imaging tumor contact length threshold of 20 mm the accuracy for diagnosing microscopic extracapsular extension was superior to that of conventional magnetic resonance imaging criteria (82% vs 67%, p = 0.015). We developed a predicted probability plot curve of extracapsular extension according to magnetic resonance imaging tumor contact length. CONCLUSIONS Magnetic resonance imaging determined tumor contact length could be a promising quantitative predictor of microscopic extracapsular extension.

Robotic Transrectal Ultrasonography During Robot-Assisted Radical Prostatectomy

We evaluate the use of robotically manipulated transrectal ultrasound (TRUS) for real-time monitoring of prostate and periprostatic anatomy during robot-assisted prostatectomy (RAP). Ten patients with clinically organ-confined prostate cancer undergoing RAP underwent preoperative and real-time intraoperative biplanar TRUS evaluation using a robotically manipulated TRUS device (ViKY System; EndoControl Medical, Grenoble, France). Median patient age was 66 yr (range: 54-88), baseline prostate-specific antigen (PSA) was 5.3 (range: 1.3-17.9), and four patients (40%) had clinical high-grade and high-stage disease. Bilateral or unilateral nerve sparing was performed in nine patients (90%). Median time for ViKY System setup to insertion of the TRUS probe was 7 min (range: 4-12). Complete robotic TRUS evaluation was successful in all patients. Five patients (50%) had TRUS-visible hypoechoic lesions, confirmed cancerous on preoperative biopsy. Relevant intraoperative TRUS findings were relayed in real time to the robotic surgeon, particularly during dissection of the bladder neck and prostatic apex, during neurovascular bundle preservation, and when hypoechoic prostate lesions approximated nerve-preserving dissection. Negative margins were achieved in nine patients (90%), including cases where significant intraprostatic lesions abutted or extended through the prostate capsule. No complications occurred. We concluded that real-time robotic TRUS guidance during RAP is feasible and safe. Robotic TRUS can provide the console surgeon with valuable anatomic information, thus maximizing functional preservation and oncologic success.

Innovations in prostate biopsy strategies for active surveillance and focal therapy

Purpose of review Active surveillance and focal therapy for prostate cancer have been proposed as treatment alternatives for prostate cancer. In this review, we track the emerging technologies that will support the viability of such management strategies. Recent findings Widespread prostate-specific antigen (PSA) testing and extended prostate biopsy practice patterns have resulted in a significant increase in the diagnosis of low-risk prostate cancer. As most low-risk prostate cancers may not require radical treatment, alternatives for appropriately selected patients have been proposed and implemented – namely, active surveillance and focal therapy. Both alternatives to radical therapy require accurate mapping and precise targeting of lesions within the prostate, for which current technological shortfalls limit their clinical utility. The emerging tools that will help overcome these challenges include refined imaging modalities, three-dimensional modeling for planning and tracking intervention, elastic fusion image technology, and automated mechanical delivery of the intervention needle. Summary Current prostate biopsy technologies have largely advanced as separate entities. Further refinement of these innovations continue, but the ultimate challenge will be integrating them into one comprehensive platform.

Validation of a novel robotic-assisted partial nephrectomy surgical training model.

Study Type – Therapy (case series)