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Gregory P Zagaja

Publications and source records attributed to Gregory P Zagaja.

12 recordsLinked to original sources
PubMed2007

Dietary fatty acids correlate with prostate cancer biopsy grade and volume in Jamaican men.

PURPOSE: Jamaica has the highest incidence of prostate cancer in the world. Dietary fat is associated with prostate cancer. The Omega6 polyunsaturated fatty acids have been shown to stimulate prostate carcinogenesis and the Jamaican diet is rich in linoleic acid. We hypothesized positive correlations between Omega6 polyunsaturated fatty acid, prostate specific antigen and prostate biopsy pathology. MATERIALS AND METHODS: A total of 148 men were enrolled in Kingston, Jamaica. Serum prostate specific antigen and erythrocyte membrane polyunsaturated fatty acids were analyzed. Men with prostate specific antigen 2.6 ng/ml or greater underwent biopsy. Histopathological and statistical analyses were performed on available data. RESULTS: Of the 54 men who underwent biopsy 24 had prostate cancer, 17 had a Gleason score of 7 or greater and 11 had a tumor volume of 50% or greater. There were significant positive correlations between linoleic acid and Gleason score (p = 0.009), and the linoleic acid-to-docosahexaenoic acid (Omega3) ratio and tumor volume (p = 0.03). There was a significant negative correlation between the arachidonic acid (Omega6)-to-docosapentanoic acid (Omega3) ratio and Gleason score (p = 0.04). Statistical correlations between prostate specific antigen and polyunsaturated fatty acids were inconsistent. CONCLUSIONS: The positive correlations between linoleic acid and Gleason score, and the linoleic acid-to-docosahexaenoic acid ratio and tumor volume support studies showing that Omega6 polyunsaturated fatty acids stimulate and Omega3 polyunsaturated fatty acids inhibit prostate cancer growth. The negative correlation between the arachidonic acid-to-docosapentanoic acid ratio and Gleason score supports studies that demonstrate increased metabolism of arachidonic acid in prostate cancer to form carcinogenic metabolites, namely prostaglandin E2. Our findings support the association between dietary fatty acids and prostate cancer, and they warrant further dietary and tissue studies in high risk populations.

Aged↗
PubMed2006

Robotic-assisted laparoscopic prostatectomy: functional and pathologic outcomes with interfascial nerve preservation.

INTRODUCTION: Robotic-assisted laparoscopic radical prostatectomy (RLRP) is increasingly becoming an alternative to open and laparoscopic radical prostatectomy in the treatment of localized prostate cancer. RLRP has been associated with low morbidity, short convalescence and comparable oncologic and functional outcomes. We report our initial experience of 300 consecutive cases with selective use of interfascial nerve preservation (IFNP). METHODS: Between February 2003 and September 2005, 300 consecutive men underwent RLRP at our institution. Patients were followed prospectively with validated questionnaires. RESULTS: Mean operative time was 282 minutes with an estimated blood loss of 273 ml. The intra-operative complication rate was 2.3% with no mortality. Return to baseline (RTB) urinary function and subjective continence at 12 months were 71% and 90.2%, respectively. RTB sexual function and subjective potency at 12 months were 53% and 80.4%, respectively. Overall, the positive surgical margin (PSM) rate was 20.9%: 15.1% for pT2 and 52.1% for pT3 disease and 93.1% had an undetectable PSA (<0.1 ng/mL) with a mean follow-up of 17.3 months. Fifty-four percent of PSMs occured in a poster-lateral (PL) location. Retrospectively, IFNP was performed in 86.5% and 62.5% of pT2 and pT3 PSMs, respectively. Pathologic-T3 PSMs were found to occur significantly more often in a PL location when ipsilateral IFNP was performed when compared to non-IFNP (73% vs 33%, p=0.05). CONCLUSIONS: IFNP appears to result in favorable return of potency, however, postero-lateral PSMs appear to occur more frequently with this technique. Proper patient selection for robotic surgery and nerve-preservation appears to be critical in order to reduce PSM and optimize the oncologic efficacy of this technology.

Adult↗
PubMed2006

Minimizing knot tying during reconstructive laparoscopic urology.

OBJECTIVES: Intracorporeal knot tying during urologic reconstructive surgery is one of the most technically challenging skills of laparoscopic surgery. We describe our experience using the Lapra-Ty clip to substitute for knot tying. METHODS: Our technique for minimizing knot tying entails the use of the Lapra-Ty clip during closure of the collecting system and renal parenchyma for laparoscopic partial nephrectomy, the vesicourethral anastomosis during robotic laparoscopic radical prostatectomy, and the collecting system during laparoscopic pyeloplasty. From October 2002 to July 2005 at our institution, 75 patients underwent laparoscopic partial nephrectomy, 300 underwent robotic laparoscopic radical prostatectomy, and 14 underwent laparoscopic pyeloplasty. We reviewed the charts retrospectively for intraoperative and postoperative parameters related to the use of these clips. RESULTS: In the laparoscopic partial nephrectomy group, the mean tumor size, warm ischemia time, and estimated blood loss was 2.53 cm, 30.1 minutes, and 189 mL, respectively. Two postoperative urine leaks (2.7%) developed, and 3 patients experienced postoperative bleeding (4%). In the robotic laparoscopic radical prostatectomy group, the mean operative time was 295 minutes and the mean estimated blood loss was 303.6 mL. Only 3 patients had a urine leak (1%), and 4 patients had bladder neck contracture (1.3%). With regard to the laparoscopic pyeloplasty group, the mean operative time and estimated blood loss was 224 minutes and 36 mL, respectively. No intraoperative complications or urinary leaks occurred. CONCLUSIONS: Using the Lapra-Ty clip, we have safely and efficiently supplemented knot tying in patients undergoing reconstructive laparoscopic surgery.

Adult↗
PubMed2006

Robotic-assisted laparoscopic prostatectomy in overweight and obese patients.

OBJECTIVES: To assess outcomes of robotic laparoscopic radical prostatectomy (RLRP) in overweight and obese patients, defined as those with a body mass index (BMI) of 25 to 30 kg/m2 and greater than 30 kg/m2, respectively. METHODS: This was a nonrandomized study evaluating all of our RLRP patients. Patients were divided into three groups: BMI of 25 kg/m2 or less (group 1), BMI greater than 25 kg/m2 and less than 30 kg/m2 (group 2), and BMI of 30 kg/m2 or more (group 3). Patients were evaluated prospectively with the validated Rand 36-Item Health Survey (version 2) and with the University of California, Los Angeles Prostate Cancer Index questionnaire. RESULTS: Between February 2003 and November 2004, 150 RLRPs were performed at our center. Average follow-up was 8 months. Groups 1, 2, and 3 had 39, 65, and 46 patients, respectively. Average BMIs for all three groups were statistically different (P < 0.01). When compared with group 1, open conversion rates, hospital stay, positive margin, and complication rates were not statistically different for groups 2 or 3. Operative time (P < 0.004) and estimated blood loss (P < 0.03), however, were statistically greater for group 3 compared with group 1. Transfusion rate was highest in group 2 (P = 0.04 compared with group 1). Prostate weights were also statistically greater in groups 2 (P = 0.003) and 3 (P = 0.02) compared with group 1. Overall, BMI did not increase perioperative and postoperative morbidity. CONCLUSIONS: Robotic laparoscopic radical prostatectomy is safe in overweight and obese patients and might be the surgical management of choice in this subset of patients. Further long-term follow-up with more patients is required to verify this initial observation.

Adult↗
PubMed2006

Robotic-assisted laparoscopic prostatectomy: first 100 patients with one year of follow-up.

OBJECTIVES: To report our initial experience of 100 patients with robotic-assisted laparoscopic radical prostatectomy. Continued technological advances have expanded our armamentarium of minimally invasive devices and techniques to offer our patients. Robotic-assisted laparoscopic radical prostatectomy has been adopted at many centers. METHODS: This was a nonrandomized prospective study evaluating our initial 100 patients who underwent robotic-assisted laparoscopic radical prostatectomy. The follow-up data were obtained prospectively using the validated Rand 36-item health survey, version 2, and the University of California, Los Angeles, Prostate Cancer Index preoperatively and at 1, 3, 6, and 12 months postoperatively. Patients who required open conversion were excluded from the outcome analysis. Patients who received a sural nerve graft were excluded from the operative analysis. RESULTS: The average age and body mass index of all patients were 58.4 years (range 42 to 70) and 28.5 kg/m2 (range 18.1 to 50.6), respectively, with a median follow-up of 12 months. The average prostate-specific antigen level was 6.07 ng/mL. Seven patients required conversion to an open technique, and four underwent sural nerve grafting. The positive surgical margin rate was 16% (15 of 92). Using the Rand 36-item health survey, version 2, and the University of California, Los Angeles, Prostate Cancer Index health surveys, the average percentage of return to baseline urinary function was 52%, 70%, 79%, and 84% at 1, 3, 6, and 12 months, respectively. The overall average percentage of return to baseline sexual function was 51%, 58%, 66%, and 80% at 1, 3, 6, and 12 months, respectively. CONCLUSIONS: Robotic-assisted laparoscopic radical prostatectomy is a safe and efficient method for achieving prostate cancer control even during the initial learning curve for this procedure.

Adult↗
PubMed2006

Impact of surgical margin status on long-term cancer control after radical prostatectomy.

OBJECTIVE: To determine whether previously described technical modifications that significantly decreased the positive surgical margin (PSM) rate have translated into improved long-term cancer control, as SM status is generally recognized as an independent risk factor for biochemical recurrence (BR) after radical retropubic prostatectomy (RRP), and is the only factor that can be modified by surgical technique. PATIENTS AND METHODS: Between March 1994 and December 2004, 996 consecutive patients had RRP as the sole treatment for clinically localized prostate cancer. The surgery was done by one surgeon (C.B.B.) and the data were prospectively reviewed. RESULTS: The overall PSM rate was 8.8%; the PSM rate by pathological stage was 1.7%, 24.2% and 27.1% for men with pT2, pT3a and pT3b disease, respectively (P < 0.001). In all, 968 of 996 (97.2%) patients were available for the follow-up (mean 6.4 years); 69 of 883 (7.8%) with negative SMs (NSMs) developed BR, vs 29 of 85 (34%) with PSMs (P < 0.001). The actuarial 5- and 10-year biochemical disease-free survival was 92.1% and 89.6%, and 70.6% and 59.9%, for patients with NSM and PSM, respectively (P < 0.001). On multivariate analysis, PSM, pathological stage and Gleason grade were the strongest predictors of BR (P < 0.001). The preoperative prostate-specific antigen level, and clinical stage T1c and T2a disease were not associated with recurrence. The hazard ratio (95% confidence interval) for BR in patients with PSMs was 3.27 (2.1-5.1). CONCLUSIONS: RRP including the previously described surgical modifications not only decreased the PSM rate but also resulted in excellent long-term cancer control. The importance of meticulous surgical technique in RRP cannot be overemphasised.

Adult↗
PubMed2006

Surgical modifications in bladder neck reconstruction and vesicourethral anastomosis during radical retropubic prostatectomy to reduce bladder neck contractures.

PURPOSE: We describe surgical modifications in radical retropubic prostatectomy (RRP) which have significantly reduced the incidence of bladder neck contractures (BNC). MATERIALS AND METHODS: Between March 1994-July 2005, 977 men underwent a RRP by a single surgeon. Group I comprised 548 patients operated upon July 1994-December 1999, without the modifications described below. Group II comprised 429 men operated upon January 2000-December 2004, with the following surgical modifications: 1) reconstruction of the bladder neck (BN) to a diameter of 28 French; 2) placement of the posterior (6 o'clock) vesicourethral suture on mild traction before placing this suture into the bladder, allowing inspection and, if necessary, replacement of any of the previously placed sutures; 3) bladder displacement when tying the vesicourethral sutures which allows the sutures to be tied under direct vision and prevents incorporation of extraneous tissue. Data were retrospectively analyzed. RESULTS: Demographic data were comparable between groups. In group I, 31/548 (5.7%) developed a BNC compared to 1/429 (0.2%) in Group II, p < 0.001. Urinary continence (no pads/maximum of one light pad for security in 24 hours) at 12 months in the 32 patients who developed a BNC was worse when compared to patients who did not develop a BNC (58% versus 80%, p = 0.003). After excluding the patients who developed a BNC, continence rates were comparable between both groups. The positive margin rate at the BN was not adversely affected by these modifications. CONCLUSIONS: Simple, easily applied modifications to the management of the BN and vesicourethral anastomosis can substantially reduce the incidence of BNC.

Adenocarcinoma↗
PubMed2005

Modified clipless antegrade nerve preservation in robotic-assisted laparoscopic radical prostatectomy with validated sexual function evaluation.

INTRODUCTION: We present our technique for clipless antegrade neurovascular bundle preservation during robotic laparoscopic radical prostatectomy, along with short-term follow-up of our patients' sexual function. TECHNICAL CONSIDERATIONS: Using the da Vinci three-arm robotic system, we performed robotic laparoscopic radical prostatectomy using a transperitoneal approach in an antegrade fashion. After division of the bladder neck, the posterior plane of the prostate was developed distally toward the apex of the prostate in the midline. This plane was then developed completely, releasing the vascular pedicles and neurovascular bundles in a medial to lateral direction, with occasional use of bipolar cautery and without the use of clips or monopolar cautery. Patients with a minimal follow-up of 3 months who did not require open conversion were included in this study. A total of 56 patients met these inclusion criteria between February 2003 and May 2004, with a mean follow-up of 6 months. Patients were given the validated Rand Medical Outcomes Study 36-Item Health Survey, version 2, with the University of California, Los Angeles, Prostate Cancer Index preoperatively and at 1, 3, 6, and 12 months postoperatively. The overall score for both unilateral and bilateral nerve-sparing groups was 35.0, 39.7, 49.4, and 49.6 at 1, 3, 6, and 12 months postoperatively, respectively. These coincided with a return to baseline potency rate of 47%, 54%, 66%, and 69% at 1, 3, 6, and 12 months, respectively. CONCLUSIONS: Antegrade dissection of the neurovascular bundle, avoiding the use of clips or monopolar cautery during robotic laparoscopic radical prostatectomy, may result in early return of sexual function and overall outcome similar to that after radical retropubic prostatectomy.

Adult↗
PubMed2005

The core learning objectives education model: an approach to the teaching of core concepts in the clinical clerkship.

INTRODUCTION AND OBJECTIVE: The classical approach to the undergraduate medical clerkship has several limitations, including variability of clinical exposure and method of examination. As a result, the clerkship experience does not ensure exposure to and reinforcement of the fundamental concepts of a given specialty. MATERIALS AND METHODS: This article reviews the classic approach to clerkship education within the undergraduate medical education. Specific attention is placed on clinical exposure and clerkship examination. RESULTS: We describe the introduction of the Core Learning Objective (CLO) educational model at the University of Chicago Section of Urology. This model is designed to provide an efficient exposure to and evaluation of core clerkship learning objectives. CONCLUSIONS: The CLO model has been successfully initiated, focusing on both technical and clinical skill sets. The proposed model has been introduced with positive initial results and should allow for an efficient approach to the teaching and evaluation of core objectives in clerkship education.

Clinical Clerkship↗
PubMed2004

Biological effective dose for comparison and combination of external beam and low-dose rate interstitial brachytherapy prostate cancer treatment plans.

We report a methodology for comparing and combining dose information from external beam radiotherapy (EBRT) and interstitial brachytherapy (IB) components of prostate cancer treatment using the biological effective dose (BED). On a prototype early-stage prostate cancer patient treated with EBRT and low-dose rate I-125 brachytherapy, a 3-dimensional dose distribution was calculated for each of the EBRT and IB portions of treatment. For each component of treatment, the BED was calculated on a point-by-point basis to produce a BED distribution. These individual BED distributions could then be summed for combined therapies. BED dose-volume histograms (DVHs) of the prostate, urethra, rectum, and bladder were produced and compared for various combinations of EBRT and IB. Transformation to BED enabled computation of the relative contribution of each modality to the prostate dose, as the relative weighting of EBRT and IB was varied. The BED-DVHs of the prostate and urethra demonstrated dramatically increased inhomogeneity with the introduction of even a small component of IB. However, increasing the IB portion relative to the EBRT component resulted in lower dose to the surrounding normal structures, as evidenced by the BED-DVHs of the bladder and rectum. Conformal EBRT and low-dose rate IB conventional dose distributions were successfully transformed to the common "language" of BED distributions for comparison and for merging prostate cancer radiation treatment plans. The results of this analysis can assist physicians in quantitatively determining the best combination and weighting of radiation treatment modalities for individual patients.

Algorithms↗
PubMed2003

Dosimetric quality endpoints for low-dose-rate prostate brachytherapy using biological effective dose (BED) vs. conventional dose.

The purpose of this study was to compare conventional low-dose-rate prostate brachytherapy dosimetric quality parameters with their biological effective dose (BED) counterparts. To validate a model for transformation from conventional dose to BED, the postimplant plans of 31 prostate brachytherapy patients were evaluated using conventional dose-volume histogram (DVH) quality endpoints and analogous BED-DVH endpoints. Based on CT scans obtained 4 weeks after implantation, DVHs were computed and standard dosimetric endpoints V100 (volume receiving 100% of the prescribed dose), V150, V200, HI (1-[V150/V100]), and D90 (dose that 90% of the target volume received) were obtained for quality analysis. Using known and reported transformations, dose grids were transformed to BED-early (alpha/beta = 10 Gy) and BED-late (alpha/beta = 3 Gy) grids, and the same dosimetric endpoints were analyzed. For conventional, BED-early and BED-late DVHs, no differences in V100 were seen (0.896, 0.893, and 0.894, respectively). However, V150 and V200 were significantly higher for both BED-early (0.582 and 0.316) and BED-late (0.595 and 0.337), compared with the conventional (0.539 and 0.255) DVHs. D90 was significantly lower for the BED-early (103.1 Gy) and BED-late transformations (106.9 Gy) as compared with the conventional (119.5 Gy) DVHs. The conventional prescription parameter V100 is the same for the corresponding BED-early and BED-late transformed DVHs. The toxicity parameters V150 and V200 are slightly higher using the BED transformations, suggesting that the BED doses are somewhat higher than predicted using conventional DVHs. The prescription/quality parameter D90 is slightly lower, implying that target coverage is lower than predicted using conventional DVHs. This methodology can be applied to analyze BED dosimetric endpoints to improve clinical outcome and reduce complications of prostate brachytherapy.

Brachytherapy↗