Michael G. Hobart
Cleveland Clinic
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Urology | 1999
Inderbir S. Gill; Andrew C. Novick; Anoop M. Meraney; Roland N. Chen; Michael G. Hobart; Gyung Tak Sung; Jonathan Hale; Dana K. Schweizer; Erick M. Remer
OBJECTIVES Laparoscopic renal cryoablation is a developmental minimally invasive nephron-sparing treatment alternative for highly select patients with small renal tumors. We present our evolving experience with this procedure. METHODS Thirty-two patients (34 tumors) with a mean tumor size of 2.3 cm on preoperative computed tomography underwent laparoscopic renal cryoablation. As dictated by the tumor location, cryoablation was performed by either the retroperitoneal (n = 22) or the transperitoneal (n = 10) laparoscopic approach using real-time ultrasound monitoring. A double freeze-thaw cycle was routinely performed. RESULTS The mean surgical time was 2.9 hours, cryoablation time 15.1 minutes, and blood loss 66.8 mL. For a mean intraoperative ultrasonographic tumor size of 2 cm, the mean cryolesion size was 3.2 cm. The hospital stay was less than 23 hours in 22 (69%) of 32 patients. Sequential magnetic resonance imaging scans demonstrated a gradual contraction in the mean diameter of the cryolesions. Of the 20 patients who underwent a 1-year follow-up magnetic resonance imaging scan, the cryoablated tumor was no longer visible in 5. Of note, 23 patients have now undergone a 3 to 6-month follow-up computed tomography-directed biopsy of the cryoablated tumor site; the biopsy was negative for cancer in all 23 patients. No evidence of local or port-site recurrence was found during a mean follow-up of 16.2 months. CONCLUSIONS Critical long-term data regarding laparoscopic renal cryoablation, a developmental technique, are awaited. However, our initial experience is cautiously optimistic. Despite its significant potential for false-negative results, it is encouraging that the follow-up computed tomography-directed needle biopsies at 3 to 6 months were negative for cancer in 23 of 23 patients.
The Journal of Urology | 2000
Inderbir S. Gill; Dana K. Schweizer; Michael G. Hobart; Gyung Tak Sung; Eric A. Klein; Andrew C. Novick
PURPOSE Laparoscopic radical nephrectomy is usually performed by the transperitoneal approach. At our institution the retroperitoneoscopic approach is preferred. We confirm the technical feasibility of retroperitoneoscopic radical nephrectomy, even for large specimens, and compare its results with open surgery in a contemporary cohort. MATERIALS AND METHODS A total of 47 patients underwent 53 retroperitoneoscopic radical nephrectomies. Data from the most recent 34 laparoscopic cases were retrospectively compared with 34 contemporary cases treated with open radical nephrectomy. RESULTS For the 53 retroperitoneoscopic radical nephrectomies mean tumor size was 4.6 cm. (range 2 to 12), surgical time was 2.9 hours (range 1.2 to 4.5) and blood loss was 128 cc. Mean specimen weight was 484 gm. (range 52 to 1,328), and concomitant adrenalectomy was performed in 72% of patients. Mean analgesic requirement was 31 mg. morphine sulfate equivalent. Average hospital stay was 1.6 days, with 68% of patients discharged from the hospital within 23 hours of the procedure. Minor complications occurred in 8 patients (17%) and major complications occurred in 2 (4%) who required conversion to open surgery. Various parameters, including patient age, body mass index, American Society of Anesthesiologists status, tumor size (5 versus 6.1 cm.), specimen weight (605 versus 638 gm.) and surgical time (3.1 versus 3.1 hours), were comparable between patients undergoing laparoscopic (34) and open (34) radical nephrectomy. However, laparoscopy resulted in decreased blood loss (p <0.001), hospital stay (p <0.001), analgesic requirements (p <0.001) and convalescence (p = 0.005). Complications occurred in 13% of patients in the laparoscopic group and 24% in the open group. CONCLUSIONS Retroperitoneoscopy is a reliable, effective and, in our hands, the preferred technique of laparoscopic radical nephrectomy. At our institution retroperitoneoscopy has emerged as an attractive alternative to open radical nephrectomy in patients with T1-T2N0M0 renal tumors.
The Journal of Urology | 2000
Inderbir S. Gill; Gyung Tak Sung; Michael G. Hobart; Stephen J. Savage; Anoop M. Meraney; Dana K. Schweizer; Eric A. Klein; Andrew C. Novick
PURPOSE We report our single institutional experience with retroperitoneal laparoscopic radical nephroureterectomy in patients with upper tract transitional cell carcinoma and compare results to those achieved by the open technique. MATERIALS AND METHODS A total of 77 patients underwent radical nephroureterectomy for pathologically confirmed upper tract transitional cell carcinoma. Of these patients 42 underwent laparoscopic nephroureterectomy from September 1997 through January 2000 and 35 underwent open surgery. All specimens were extracted intact. Of the laparoscopic group the juxtavesical ureter and bladder cuff were excised by our novel transvesical needlescopic technique in 27 and radical nephrectomy was performed retroperitoneoscopically in all 42. Data were compared retrospectively with 35 patients undergoing open radical nephroureterectomy from February 1991 through December 1999. RESULTS Laparoscopy was superior in regard to surgical time (3.7 versus 4.7 hours, p = 0.003), blood loss (242 versus 696 cc, p <0. 0001), specimen weight (559 versus 388 gm., p = 0.04), resumption of oral intake (1.6 versus 3.2 days, p = 0.0004), narcotic analgesia requirements (26 versus 228 mg., p <0.0001), hospital stay (2.3 versus 6.6 days, p <0.0001), normal activities (4.7 versus 8.2 weeks, p = 0.002) and convalescence (8 versus 14.1 weeks, p = 0.007). Complications occurred in 5 patients (12%) in the laparoscopic group, including open conversions in 2, and in 10 (29%) in the open group (p = 0.07). Followup was shorter in the laparoscopic group (11.1 versus 34.4 months, p <0.0001). The 2 groups were similar in regard to bladder recurrence (23% versus 37%, p = 0.42), local retroperitoneal or port site recurrence (0% versus 0%) and metastatic disease (8.6% versus 13%, p = 1.00). Mortality occurred in 2 patients (6%) in the laparoscopic group and 9 (30%) in the open group. Cancer specific survival (97% versus 87%) and crude survival (97% versus 94%) were similar between both groups (p = 0.59). CONCLUSIONS In patients with upper tract transitional cell carcinoma who are candidates for radical nephroureterectomy the retroperitoneal laparoscopic approach satisfactorily duplicates established technical principles of traditional open oncological surgery, while significantly decreasing morbidity from this major procedure. Short-term oncological and survival data of the laparoscopic technique are comparable to open surgery. Although long-term followup data are not yet available, it appears that laparoscopic radical nephroureterectomy may supplant open surgery as the standard of care in patients with muscle invasive or high grade upper tract transitional cell carcinoma.
Cancer | 2001
Inderbir S. Gill; Anoop M. Meraney; Dana K. Schweizer; Stephen S. Savage; Michael G. Hobart; Gyung Tak Sung; D.R Nelson; Andrew C. Novick
The objective of the current study was to report a single‐surgeon, single‐center experience with 100 consecutive laparoscopic radical nephrectomies with intact specimen extraction, with the aim of evaluating the oncologic adequacy of the laparoscopic dissection from a technical standpoint and various parameters including the learning curve.
The Journal of Urology | 2000
Inderbir S. Gill; Robert G. Uzzo; Michael G. Hobart; Stevan B. Streem; David A. Goldfarb; Mark Noble
PURPOSE We report the technique of and initial experience with retroperitoneal laparoscopic live donor right nephrectomy for purposes of renal allotransplantation and autotransplantation. MATERIALS AND METHODS A total of 5 patients underwent retroperitoneoscopic live donor nephrectomy of the right kidney for autotransplantation in 4 and living related renal donation in 1. Indications for autotransplantation included a large proximal ureteral tumor, a long distal ureteral stricture and 2 cases of the loin pain hematuria syndrome. In all cases a 3-port retroperitoneal laparoscopic approach and a pelvic muscle splitting Gibson incision for kidney extraction were used. In patients undergoing autotransplantation the same incision was used for subsequent transplantation. RESULTS All procedures were successfully accomplished without technical or surgical complications. Total mean operating time was 5.8 hours and average laparoscopic donor nephrectomy time was 3.1 hours. Mean renal warm ischemia time, including endoscopic cross clamping of the renal artery to ex vivo cold perfusion, was 4 minutes. Average blood loss for the entire procedure was 400 cc. Radionuclide scan on postoperative day 1 confirmed good blood flow and function in all transplanted kidneys. Mean analgesic requirement was 58 mg. fentanyl. Mean hospital stay was 4 days (range 2 to 8), and convalescence was completed in 3 to 4 weeks. CONCLUSIONS In the occasional patient requiring renal autotransplantation live donor nephrectomy can be performed laparoscopically with renal extraction and subsequent transplantation through a single standard extraperitoneal Gibson incision, thus, minimizing the overall operative morbidity. Furthermore, these data demonstrate that live donor nephrectomy of the right kidney can be performed safely using a retroperitoneal approach with an adequate length of the right renal vein obtained for allotransplantation or autotransplantation.
The Journal of Urology | 2001
Inderbir S. Gill; Jihad H. Kaouk; Michael G. Hobart; Gyung Tak Sung; Dana K. Schweizer; William E. Braun
PURPOSE We report our experience with laparoscopic bilateral synchronous nephrectomy for giant symptomatic autosomal dominant polycystic kidney disease (ADPKD) and compare outcome data with open bilateral nephrectomy. MATERIALS AND METHODS Since March 1998, 10 patients underwent bilateral synchronous laparoscopic nephrectomy for giant symptomatic ADPKD. A 3 port retroperitoneal laparoscopic approach was used to secure the renal hilum and mobilize the kidney. Intact specimen extraction was performed through a midline infraumbilical extraperitoneal incision. The patient was then repositioned for the contralateral retroperitoneoscopic nephrectomy, with the second specimen also delivered through the same infraumbilical incision. Data were retrospectively compared with 10 patients who had undergone bilateral synchronous open nephrectomy for ADPKD between 1981 and 1992. RESULTS Patients in the laparoscopic and open groups were comparable in regard to age (53 versus 47 years, p = 0.54) and Anesthesiologist Society of America class (3 versus 3, p = 0.84) but patients in the laparoscopic group were significantly more obese (body mass index 35.9 versus 23.8, p = 0.02). For comparable total specimen weights (3 versus 3 kg, p = 0.69) surgical time was longer in the laparoscopic group (4.4 versus 3.8 hours, p = 0.007). However, the laparoscopic group was superior in regard to blood loss (150 versus 325 cc, p = 0.05), postoperative requirement of nasogastric tube (10% versus 100%, p = 0.0001), narcotic analgesics (34.2 versus 120.4 mg. morphine sulfate equivalent, p = 0.03) and hospital stay (1.5 versus 9 days, p = 0.004). Complications occurred in 5 patients (50%) in the laparoscopic group and 4 (40%) in the open group (p = 0.66). No laparoscopic case was converted to open surgery. CONCLUSIONS Synchronous bilateral retroperitoneal laparoscopic nephrectomy for giant symptomatic adult polycystic kidney disease is feasible, safe and efficacious, and can be performed either before or after renal transplantation. Compared to open surgery, the laparoscopic approach results in significantly shorter hospital stay, decreased morbidity and quicker recovery. Laparoscopy is currently our technique of choice in this setting.
Transplantation | 2000
Anil Kapoor; Ken Morita; Tara M. Engeman; Shoji Koga; Evan M. Vapnek; Michael G. Hobart; Robert L. Fairchild
BACKGROUND Our goal was to test the intragraft mRNA expression and production of two chemokines that are potent chemoattractants for antigen-primed T cells, interferon-gamma inducible protein 10 (IP-10) and monokine-induced by IFN-gamma, (Mig), in allogeneic heart grafts. METHODS Syngeneic or allogeneic A/J (H-2a) hearts were heterotopically transplanted to wild-type, CD4-/-, CD8alpha-/-, or IFN-gamma-/- C57BL/6 (H-2b) recipients. To test expression of IP-10 and Mig, grafts were removed 1-8 days posttransplant for RNA isolation and Northern blot analysis. To test the potential recipient leukocyte populations mediating intraallograft expression of IP-10 and Mig, recipients were treated with anti-NK 1.1, anti-CD4, and/or anti-CD8 monoclonal antibodies before transplantation. RESULTS Allogeneic heart grafts transplanted to wild-type, but not IFN-gamma-/-, recipients expressed IP-10 and Mig at day +2 posttransplant that increased thereafter until rejection was completed. Expression of IP-10 and Mig in isografts was low or undetectable. Cardiac allografts from CD8+ T cell depleted, but not NK cell or CD4+ T cell depleted, recipients had low to undetectable expression of IP-10 and Mig on day +2 posttransplant. Similarly, cardiac allografts from CD8-/-, but not CD4-/-, recipients had low to undetectable expression of IP-10 and Mig on day +2 posttransplant. CONCLUSIONS Early intraallograft expression of Mig and IP-10 during primary rejection of cardiac allografts is dependent on the activities of recipient CD8+ T cells.
Transplantation | 1998
Michael G. Hobart; Charles S. Modlin; Anil Kapoor; Navdeep Boparai; Barbara Mastroianni; Doreen Papajcik; Stuart M. Flechner; David A. Goldfarb; Rosemaree Fischer; Kiaran J. O'Malley; Andrew C. Novick
BACKGROUND To maximize the renal donor pool, cadaveric pediatric en bloc kidneys have been transplanted as a dual unit by some transplant centers. We compared the short- and long-term outcomes of adult recipients of cadaveric pediatric en bloc renal transplants versus those of matched recipients of cadaveric adult kidneys. METHODS Thirty-three adults who received pediatric en bloc kidney transplants between April 1990 and September 1997 were retrospectively identified and were compared with 33 matched adults who received adult cadaveric kidney transplants. The groups were identical for transplantation era, immunosuppression, recipient sex, race, cause of renal failure, mean weight, and follow-up duration (37.8 vs. 37.5 months). The mean recipient age study versus control was lower (36.3 vs. 48.9 years, P=0.0003). Results. There was no difference between the en bloc and adult donor groups in the 3-year patient survival rates (95% vs. 87%, P=0.16) or the 3-year graft survival rates (87.3% vs. 84.2%, P=0.35). Further, there was no difference in en bloc patient or en bloc graft survival time stratified by recipient age (14-44 vs. >45 years, P=0.11), en bloc donor age (<24 vs. >24 months, P=0.39), or recipient weight (<60, 61-75, >75 kg; P=0.60). Differences in serum creatinine (mg/dl) for the en bloc versus the control group at the time of discharge (3.0 vs. 7.8 mg/dl, P=0.06), at 1 year (1.4 vs. 2.0 mg/dl, P=0.06), and at 2 years (1.1 vs. 1.6 mg/dl, P=0.14) had dissipated by the time of the 5-year follow-up examination (1.1 vs. 1.6 mg/dl, P=0.14). Vascular complications were more prevalent in the en bloc group: renal vein thrombosis (one case), thrombosis of donor aorta (two cases), arterial thrombosis of one renal moiety (two cases), and renal artery stenosis (two cases). There were no differences between groups in delayed graft function, acute or chronic rejection, posttransplant hypertension, posttransplant protein-uria, or long-term graft function. CONCLUSIONS Collectively, these data indicate that transplanting pediatric en bloc kidneys into adult recipients results in equivalent patient and graft survival compared with adult cadaveric kidneys. Further, the data also suggest that pediatric en bloc kidneys need not be strictly allocated based on recipient weight or age criteria.
Transplantation | 1996
Nelson Goes; Joan Urmson; Michael G. Hobart; Philip F. Halloran
We examined the expression of MHC class I and II in the arterial endothelium of interferon-gamma (IFN-gamma, GKO) and IFN-gamma-R (IFN-gamma-R, GRKO) gene knockout mice in comparison with mice with intact IFN-gamma and IFN-gamma-R genes, BALB/c and 129Sv/J wild-type, respectively. The GKO and GRKO were produced by gene targeting. MHC class I and II expression was assessed by mAb binding to frozen tissue (kidney, spleen, heart, liver) sections by immunoperoxidase staining in the basal state and after various stimuli: allogeneic cells, oxazolone skin sensitization, LPS, and rIFN-gamma. As controls, we also examined the expression of two other IFN-gamma inducible genes present in the endothelium, Ly-6 and ICAM-1. We found that basal class I expression was present in the small arteries and arterioles of BALB/c and 129Sv/J wild-type mice but absent from arterial endothelium of GKO and GRKO mice. Class I was induced in the endothelium of BALB/c and 129Sv/J wild-type mice by three in vivo stimuli: allogeneic, LPS, and oxazolone, whereas class II was only induced after allogeneic stimulus. Administration of rIFN-gamma induced class I in the endothelium of GKO and BALB/c wild-type mice. The basal expression of Ly-6 and ICAM-1 was similar in the arteries of GKO and BALB/c wild-type mice, indicating that, the basal expression of these proteins in endothelium is IFN-gamma independent, unlike class I. In summary, basal class I expression in arterial endothelium is not constitutive as previously believed, but is dependent on basal IFN-gamma production. IFN-gamma has an essential role in the induction of class I and II expression in arterial endothelium. The fact that MHC class I is induced in endothelium may be useful therapeutically for reduction of immune recognition in transplantation.
The Journal of Urology | 1999
Michael G. Hobart; Inderbir S. Gill; Dana K. Schweizer; Emannuel L. Bravo
PURPOSE Needlescopic adrenalectomy, partially incorporating 2 mm. instrumentation, is currently our preferred technique for transperitoneal endoscopic adrenalectomy. Although this minimally invasive technique results in decreased morbidity and shorter hospital stay, to our knowledge financial implications vis-à-vis open adrenalectomy have not been elucidated. We retrospectively compared the costs of needlescopic adrenalectomy to traditional open adrenalectomy. MATERIALS AND METHODS From September 1997 through March 1998, 15 patients underwent needlescopic adrenalectomy. Financial records of these patients were compared to those of 15 contemporary patients undergoing open adrenalectomy between January 1995 and May 1997. Adrenal pathology and tumor size were comparable between the 2 groups. Yearly costs were adjusted for inflation to 1998 dollars using a 4% annual rate. Needlescopic financial data are expressed as a ratio of open adrenalectomy costs, which are expressed as a unit of 1. RESULTS Overall, needlescopic adrenalectomy resulted in a 17.9% decrease in total hospital costs compared to open adrenalectomy. While the needlescopic approach was associated with an 18.1% increase in intraoperative costs, postoperative costs were 63.4% lower. CONCLUSIONS These data demonstrate that in addition to providing a shorter hospital stay, decreased morbidity and quicker recovery, needlescopic adrenalectomy also is 17.9% less expensive than open adrenalectomy.