Marcelo A. Orvieto
University of Chicago
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Featured researches published by Marcelo A. Orvieto.
European Urology | 2010
Rafael F. Coelho; Kenneth J. Palmer; Bernardo Rocco; Ravendra R. Moniz; Sanket Chauhan; Marcelo A. Orvieto; Geoff Coughlin; Vipul R. Patel
BACKGROUND Perioperative complications following robotic-assisted radical prostatectomy (RARP) have been previously reported in recent series. Few studies, however, have used standardized systems to classify surgical complications, and that inconsistency has hampered accurate comparisons between different series or surgical approaches. OBJECTIVE To assess trends in the incidence and to classify perioperative surgical complications following RARP in 2500 consecutive patients. DESIGN, SETTING, AND PARTICIPANTS We analyzed 2500 patients who underwent RARP for treatment of clinically localized prostate cancer (PCa) from August 2002 to February 2009. Data were prospectively collected in a customized database and retrospectively analyzed. INTERVENTION All patients underwent RARP performed by a single surgeon. MEASUREMENTS The data were collected prospectively in a customized database. Complications were classified using the Clavien grading system. To evaluate trends regarding complications and radiologic anastomotic leaks, we compared eight groups of 300 patients each, categorized according the surgeons experience (number of cases). RESULTS AND LIMITATIONS Our median operative time was 90min (interquartile range [IQR]: 75-100min). The median estimated blood loss was 100ml (IQR:100-150ml). Our conversion rate was 0.08%, comprising two procedures converted to standard laparoscopy due to robot malfunction. One hundred and forty complications were observed in 127 patients (5.08%). The following percentages of patients presented graded complications: grade 1, 2.24%; grade 2, 1.8%; grade 3a, 0.08%; grade 3b, 0.48%; grade 4a, 0.40%. There were no cases of multiple organ dysfunction or death (grades 4b and 5). There were significant decreases in the overall complication rates (p=0.0034) and in the number of anastomotic leaks (p<0.001) as the surgeons experience increased. CONCLUSIONS RARP is a safe option for treatment of clinically localized PCa, presenting low complication rates in experienced hands. Although the robotic system provides the surgeon with enhanced vision and dexterity, proficiency is only accomplished with consistent surgical volume; complication rates demonstrated a tendency to decrease as the surgeons experience increased.
Journal of Endourology | 2008
Edward M. Gong; Marcelo A. Orvieto; Kevin C. Zorn; Alvaro Lucioni; Gary D. Steinberg; Arieh L. Shalhav
PURPOSE Partial nephrectomy has been established as a standard of care for T(1a) renal tumors. Laparoscopic partial nephrectomy (LPN) has been described as more difficult to perform than open partial nephrectomy (OPN). We compare our series of LPN and OPN. PATIENTS AND METHODS From October 2002 to January 2006, 76 LPNs were performed for patients with clinical T(1a) tumors. These patients were matched with a cohort of patients who underwent OPN for solitary tumors of 4 cm or smaller in diameter. The cohorts were compared with regard to demographics, perioperative data, and outcomes. RESULTS The patient populations were demographically similar. Although mean tumor size was smaller in the laparoscopic cohort (2.5 v 2.9 cm, P=0.002), the OPN cohort demonstrated shorter operative (193 v 225 min, P=0.004) and ischemia times (20.5 v 32.8 min). LPN was associated with less blood loss (212 v 385 mL, P<0.001) and shorter hospital stay (2.5 v 5.6 days, P<0.001), however. One positive margin occurred in each of the LPN and OPN cohorts. Intraoperative complications were similar, although LPN was associated with fewer postoperative complications. Of note, two LPN (2.6%) patients had emergent reoperation and complete nephrectomy because of postoperative hemorrhage. CONCLUSIONS Despite increased operative and ischemia times, LPN patients demonstrated quicker recovery and fewer postoperative complications. Two patients in the LPN group, however, had emergent complete nephrectomy because of hemorrhage. We conclude that LPN is still an evolving alternative to OPN in patients with small renal tumors.
BJUI | 2010
Vipul R. Patel; Rafael F. Coelho; Sanket Chauhan; Marcelo A. Orvieto; Kenneth J. Palmer; Bernardo Rocco; Ananthakrishnan Sivaraman; Geoff Coughlin
Study Type – Therapy (case series) Level of Evidence 4
Urology | 2008
Edward M. Gong; Kevin C. Zorn; Marcelo A. Orvieto; Alvaro Lucioni; Lambda P. Msezane; Arieh L. Shalhav
OBJECTIVES Artery-only occlusion (AO) has been used during nephron-sparing surgery to reduce ischemic damage. However, this has not been demonstrated in laparoscopic partial nephrectomy (LPN). We compared our experience with AO and both artery and vein occlusion (AV) in LPN to optimize the method of ischemia. METHODS This retrospective case-control study identified 25 patients who underwent AO during LPN and matched them to a cohort of 53 patients who underwent LPN with AV. The groups were compared for ischemia time, blood loss, transfusion rate, and renal function. RESULTS The 2 cohorts were comparable on demographic data. Blood loss was similar, with AO and AV demonstrating equivalent transfusion rates. The 2 cohorts had similar warm ischemia times. Positive margin rate was not affected by venous backflow in the AO cohort (0% AO vs 1.9% AV, P = .679). No significant postoperative change in creatinine (Cr) or creatinine clearance (CrCl) was seen for AO; however, a significant change in Cr and CrCl was seen in AV. CONCLUSIONS AO during LPN does not lead to a greater blood loss or an increased warm ischemia time. The benefit of AO on renal function is significant and requires further investigation.
BJUI | 2011
Marcelo A. Orvieto; Rafael F. Coelho; Sanket Chauhan; Kenneth J. Palmer; Bernardo Rocco; Vipul R. Patel
Study Type – Therapy (case series)
BJUI | 2006
Marcelo A. Orvieto; Nejd F. Alsikafi; Arieh L. Shalhav; Brett A. Laven; Gary D. Steinberg; Gregory P. Zagaja; Charles B. Brendler
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.
BJUI | 2012
Rafael F. Coelho; Sanket Chauhan; Ananthakrishnan Sivaraman; Kenneth J. Palmer; Marcelo A. Orvieto; Bernardo Rocco; Geoff Coughlin; Vipul R. Patel
Study Type – Therapy (case series)
European Urology | 2010
Rafael F. Coelho; Sanket Chauhan; Marcelo A. Orvieto; Kenneth J. Palmer; Bernardo Rocco; Vipul R. Patel
BACKGROUND Positive surgical margin (PSM) after radical prostatectomy (RP) has been shown to be an independent predictive factor for cancer recurrence. Several investigations have correlated clinical and histopathologic findings with surgical margin status after open RP. However, few studies have addressed the predictive factors for PSM after robot-assisted laparoscopic RP (RARP). OBJECTIVE We sought to identify predictive factors for PSMs and their locations after RARP. DESIGN, SETTING, AND PARTICIPANTS We prospectively analyzed 876 consecutive patients who underwent RARP from January 2008 to May 2009. INTERVENTION All patients underwent RARP performed by a single surgeon with previous experience of >1500 cases. MEASUREMENTS Stepwise logistic regression was used to identify potential predictive factors for PSM. Three logistic regression models were built: (1) one using preoperative variables only, (2) another using all variables (preoperative, intraoperative, and postoperative) combined, and (3) one created to identify potential predictive factors for PSM location. Preoperative variables entered into the models included age, body mass index (BMI), prostate-specific antigen, clinical stage, number of positive cores, percentage of positive cores, and American Urological Association symptom score. Intra- and postoperative variables analyzed were type of nerve sparing, presence of median lobe, percentage of tumor in the surgical specimen, gland size, histopathologic findings, pathologic stage, and pathologic Gleason grade. RESULTS AND LIMITATIONS In the multivariable analysis including preoperative variables, clinical stage was the only independent predictive factor for PSM, with a higher PSM rate for T3 versus T1c (odds ratio [OR]: 10.7; 95% confidence interval [CI], 2.6-43.8) and for T2 versus T1c (OR: 2.9; 95% CI, 1.9-4.6). Considering pre-, intra-, and postoperative variables combined, percentage of tumor, pathologic stage, and pathologic Gleason score were associated with increased risk of PSM in the univariable analysis (p<0.001 for all variables). However, in the multivariable analysis, pathologic stage (pT2 vs pT1; OR: 2.9; 95% CI, 1.9-4.6) and percentage of tumor in the surgical specimen (OR: 8.7; 95% CI, 2.2-34.5; p=0.0022) were the only independent predictive factors for PSM. Finally, BMI was shown to be an independent predictive factor (OR: 1.1; 95% CI, 1.0-1.3; p=0.0119) for apical PSMs, with increasing BMI predicting higher incidence of apex location. Because most of our patients were referred from other centers, the biopsy technique and the number of cores were not standardized in our series. CONCLUSIONS Clinical stage was the only preoperative variable independently associated with PSM after RARP. Pathologic stage and percentage of tumor in the surgical specimen were identified as independent predictive factors for PSMs when analyzing pre-, intra-, and postoperative variables combined. BMI was shown to be an independent predictive factor for apical PSMs.
BJUI | 2012
Marcelo A. Orvieto; Michael C. Large; Mohan S. Gundeti
Whats known on the subject? and What does the study add?
BJUI | 2007
Brett A. Laven; Kenneth E. Kasza; David E. Rapp; Marcelo A. Orvieto; Mark B. Lyon; John J. Oras; David G. Beiser; Terry L. Vanden Hoek; Hyunjin Son; Arieh L. Shalhav
To assess, in a pilot study, the feasibility of delivering a microparticulate ice slurry (MPS) to provide regional hypothermia, as renal cooling during laparoscopic procedures is cumbersome and inefficient.