Search PubMed⌕ Search

Biomedical subjects

Louis R Kavoussi

Publications and source records attributed to Louis R Kavoussi.

At least 37 records · Page 2Linked to original sources
PubMed2006

Trends in the operative management of renal tumors over a 14-year period.

OBJECTIVE: To review the trends in the operative management of renal tumours over a 14-year period at a university hospital, as the therapeutic options available for treating renal tumours have increased over the past decade. PATIENTS AND METHODS: The study was a retrospective chart review of 1621 consecutive patients undergoing treatment for renal tumours from January 1991 to March 2005. The characteristics assessed included patient demographics, tumour size, operative duration and treatment. RESULTS: During the study period, 624 (38.6%) open, 883 (54.6%) laparoscopic and 111 (6.7%) percutaneous approaches were performed. The number of renal tumours treated increased annually, as did the use of minimally invasive techniques (93.4% in 2005). Conversely, the number of open surgical treatments used declined both absolutely and proportionally. Over the study period, for tumours of 7 cm, open radical nephrectomy (ORN) was the most common method of treatment over all years. However, since 2002, laparoscopic radical nephrectomy (LRN) surgery has been increasingly used over ORN for treating this tumour group (73% LRN vs 19.2% ORN in 2004). CONCLUSION: The available treatment options for renal tumours have increased significantly since the early 1990s. At a university hospital in which there are physicians with a specific interest in minimally invasive surgery and ablative treatments, minimally invasive approaches have become the standard treatment.

Aged↗
PubMed2005

Pain control requirements for percutaneous ablation of renal tumors: cryoablation versus radiofrequency ablation--initial observations.

PURPOSE: To retrospectively compare the pain control requirements of patients undergoing computed tomography (CT)-guided percutaneous radiofrequency (RF) ablation with those of patients undergoing CT-guided percutaneous cryoablation of small (< or = 4-cm) renal tumors. MATERIALS AND METHODS: The study was HIPAA compliant and received institutional review board exemption; informed consent was not required. Medical and procedure records of patients who underwent RF ablation and cryoablation of renal tumors from June 19, 2003, to February 28, 2004, were retrospectively reviewed for clinical data, tumor characteristics, and anesthesia information. During the study period, 10 men (mean age, 66.5 years) underwent cryoablation of 11 renal lesions, and 14 patients (11 men, four women; mean age, 68.1 years) underwent RF ablation of 15 renal tumors. Analgesic and sedative requirements during the procedure were compared. Standard anesthesia consisted of 5 mL of 1% lidocaine injected locally, and conscious sedation consisted of 50 microg of fentanyl and 1 mg of midazolam administered intravenously. The Fisher exact test and Student t test were used to compare clinical factors and drug requirements between the two groups. RESULTS: There was no difference in terms of patient demographics, tumor diameter, or distribution of central versus noncentral lesions between the two groups. Cryoablation was associated with a significantly lower dose of fentanyl (165.0 microg [RF group] vs 75.0 microg [cryoablation group]; P < .001) and midazolam (2.9 mg [RF group] vs 1.6 mg [cryoablation group]; P = .026). In the RF group, one patient required general anesthesia, one patient required supplemental narcotics (5 mg of oxycodone) and sedatives (1 mg lorezapam), and one patient became apneic for a brief interval after receiving additional narcotics for pain during the procedure. An additional RF session was terminated early in one patient because of pain, and further medication could not be administered owing to bradycardia. No patients in the cryoablation group required any additional or alternate anesthetics. CONCLUSION: Image-guided percutaneous cryoablation of small (< or = 4-cm) renal lesions appears to require less analgesia than RF ablation. Prospective trials with validated pain scales are needed to examine this further.

Aged↗
PubMed2005

Modeling the cost of management options for stage I nonseminomatous germ cell tumors: a decision tree analysis.

PURPOSE: Patients with clinical stage I nonseminomatous germ cell tumors (NSGCTs) have been managed with surveillance, chemotherapy, or retroperitoneal lymphadenectomy (RPLND) with similar survival outcomes. Cost factors influencing the choice of therapy were evaluated using computer-based decision analysis. METHODS: A detailed model was developed that integrates projected costs for more than 60 possible treatment outcomes. It incorporates primary, adjuvant, and salvage chemotherapy, primary and post-chemotherapy RPLND, and both laparoscopic and open surgical approaches. Starting values and probabilities were derived from a comprehensive meta-analysis of the last 25 years of testes cancer literature. Hypothesis testing was performed using sensitivity analysis. RESULTS: The model predicts a cost premium for both primary chemotherapy (18.7%) and RPLND (51.7%) compared with surveillance. If laparoscopic RPLND was practiced, the cost premium for primary surgery (29.1%) approached that of chemotherapy (26.4%). Open RPLND was 1.25x as costly as laparoscopic RPLND, primarily because of longer hospitalization. The choice of open RPLND yielded a 6.9% cost premium for a surveillance program in this model. For such a program, primary chemotherapy became cost advantageous when the probability of recurrence during surveillance was more than 46%. CONCLUSION: This model allows a variety of treatment cost hypotheses to be tested. Primary RPLND is never cost advantageous over surveillance or primary chemotherapy. Surgical costs can significantly increase the overall cost of a surveillance program. In stage I patients with high-risk tumor characteristics, primary chemotherapy may have a cost advantage over surveillance.

Antineoplastic Agents↗
PubMed2005

Laparoscopic retroperitoneal lymph node dissection: duplication of open technique.

Laparoscopic retroperitoneal lymph node dissection has been used to stage germ cell testicular cancer. Since its initial description, this minimally invasive procedure has evolved into a therapeutic operation that adheres to established strict oncologic principles. A modified template dissection that fully duplicates the open technique is now routinely performed at our institution. We describe and show in the accompanying video segments a laparoscopic modified template dissection.

Humans↗
PubMed2005

Small cell carcinoma of epididymis: multimodal therapy.

Extrapulmonary small cell carcinoma is an infrequent tumor that can occur in various organs. Although a few sporadic reports about extrapulmonary small cell carcinoma have been published, much remains to be uncovered about the clinical features, optimal treatment, and natural history. We present a case of small cell carcinoma of the epididymis with retroperitoneal recurrence, an exceedingly rare tumor with behavior and treatment not well characterized. Multimodal therapy with chemotherapy and retroperitoneal lymph node dissection was necessary to manage this aggressive disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Laparoscopic temporary packing for hemostasis.

Control of bleeding from the renal parenchyma remains one of the challenges of laparoscopic partial nephrectomy. If adjuvant measures fail, packing of the surgical bed may achieve hemostasis. We report a novel series of temporary laparoscopic packing of the surgical bed with minimally invasive kidney surgery. Technique and potential complications are also discussed.

Aged↗
PubMed2005

Leiomyomas of the kidney: emphasis on conservative diagnosis and treatment.

Leiomyomas are benign mesenchymal tumors that rarely occur in the kidney. We present the reports of three renal leiomyomas diagnosed and treated at our institution during the past 10 years. On the basis of our experience, preoperative diagnosis may be possible through image-guided percutaneous biopsy, and conservative treatment with either expectant management or minimally invasive nephron-sparing surgery should always be considered.

Adult↗
PubMed2005

Laparoscopic retroperitoneal lymph node dissection after prior open retroperitoneal lymphadenectomy and chemotherapy.

Laparoscopic retroperitoneal lymphadenectomy for testicular cancer is a challenging surgical procedure. Several factors can increase the difficulty, including prior chemotherapy or open surgery. We present a case of a laparoscopic "redo" postchemotherapy nodal dissection to treat a residual retroperitoneal mass in a patient with non-seminomatous germ cell tumor. This approach allowed rapid recovery, and at 2.5 years after surgery no evidence of tumor recurrence was seen.

Adult↗
PubMed2005

Laparoscopic ureteral reimplantation: a simplified dome advancement technique.

Laparoscopic Boari flap reimplantation has been used to treat long distal ureteral strictures. This technique requires extensive bladder mobilization and complex intracorporeal suturing. This demonstrates a novel laparoscopic bladder dome advancement approach for ureteral reimplantation. This technique obviates the need for bladder pedicle dissection and simplifies the required suturing.

Humans↗
PubMed2005

Imaging following cryoablation of a renal lesion.

BACKGROUND: An 81-year-old man presented with a history of right nephrectomy for renal cell carcinoma, chronic renal insufficiency and implanted defibrillator. He was asymptomatic. Contrast-enhanced CT and MRI were contraindicated. INVESTIGATIONS: Non-contrast CT, positron emission tomography (PET), fused PET-CT and Doppler ultrasound. DIAGNOSIS: Small exophytic left midpole renal tumor, 3.7 cm in size. MANAGEMENT: Percutaneous CT-guided renal cryoablation, followed up with PET-CT imaging.

Aged↗
PubMed2005

Complete daVinci versus laparoscopic pyeloplasty: cost analysis.

BACKGROUND AND PURPOSE: Computer-assisted pyeloplasty with the daVinci system is an emerging technique to treat ureteropelvic junction (UPJ) obstruction. A relative cost analysis was performed assessing this technology in comparison with purely laparoscopic pyeloplasty. PATIENTS AND METHODS: Eight patients underwent computer-assisted (daVinci) dismembered pyeloplasty (CP) via a transperitoneal four-port approach. They were compared with 13 patients who underwent purely laparoscopic pyeloplasty (LP). All patients had a primary UPJ obstruction and were matched for age, sex, and body mass index. The cost of equipment and capital depreciation for both procedures, as well as assessment of room set-up time, takedown time, and personnel were analyzed. Surgeons and nursing staff for both groups were experienced in both laparoscopy and daVinci procedures. One- and two-way financial analysis was performed to assess relative costs. RESULTS: The mean set-up and takedown time was 71 minutes for CP and 49 minutes for LP. The mean length of stay was 2.3 days for CP and 2.5 days for LP. The mean operating room (OR) times for CP and LP were 176 and 210 minutes, respectively. There were no complications in either group. One-way cost analysis with an economic model showed that LP is more cost effective than CP at our hospital if LP OR time is <338 minutes. With adjustment to a volume of 500 daVinci cases/year, CP is still not as cost effective as LP. Two-way sensitivity analysis shows that in-room time must still be <130 minutes and yearly cases must be >500 to obtain cost equivalence for CP. CONCLUSIONS: Perioperative parameters for CP are encouraging. However, the costs are a clear disadvantage. In our hospital, it is more cost effective to teach and perform LP than to perform CP.

Adult↗
PubMed2005

Pathological stage does not alter the prognosis for renal lesions determined to be stage T1 by computerized tomography.

PURPOSE: Pathological stage has been the most widely used prognosticator for evaluating surgically managed cases of renal cell carcinoma. Minimally invasive surgical approaches are being increasingly used to treat small masses for which traditionally pathological information is lacking (morcellation) or absent (radio frequency ablation or cryoablation). Preoperative cross-sectional imaging by computerized tomography (CT) or magnetic resonance imaging has been used to stage renal tumors clinically but it can lead to variances with traditional pathological staging systems, particularly with respect to microscopic invasion beyond the renal capsule. In this study we assessed whether radiographically staged clinical T1 lesions that were pathological T1 behave differently than those that were clinical stage T1 and up staged to pT3a. MATERIALS AND METHODS: The records of 296 patients who underwent surgical treatment for renal cell carcinoma at The Johns Hopkins Hospital between 1990 and 1999 were retrospectively reviewed. All patients had undergone preoperative CT or magnetic resonance imaging, which was used to assign a clinical stage and size (largest diameter) to each tumor in accordance with the 1997 TNM staging system. Following surgical resection pathological stage, size and tumor grade were determined. Only the 186 patients with clinical T1 tumors were included in this analysis. RESULTS: Of the 186 patients who were clinically found to have T1 lesions 125 (67%) had pathological T1 and 57 (31%) had pathological T3a lesions. All surgical margins and lymph nodes were negative at surgical resection. Mean tumor size +/- SD was 3.9 +/- 1.5 cm for pT1 lesions and 3.8 +/- 1.5 cm for pT3a lesions. When comparing these pathological groups using Kaplan-Meier analysis, 5-year recurrence-free survival was not statistically different in patients with pT1 and pT3a lesions (90.6 and 97.5%, respectively). CONCLUSIONS: Patients in whom the initial classification of T1 renal cell carcinoma by CT was up graded to T3a on pathological analysis (invasion of fat within Gerota's fascia) showed the same recurrence-free survival rate as patients with pathologically confirmed T1 lesions. Thus, smaller tumors (less than 7 cm) that are up graded to T3a based on capsule invasion behave much like T1 tumors and exact pathological T staging does not appear to impact overall survival.

Carcinoma, Renal Cell↗
PubMed2005

Exploring the learning curve, pathological outcomes and perioperative morbidity of laparoscopic partial nephrectomy performed for renal mass.

PURPOSE: We investigated the learning curve, pathological results and perioperative morbidity of laparoscopic partial nephrectomy (LPN). MATERIALS AND METHODS: The records of all LPN cases at our institution between January 1999 and March 2004 were reviewed. Of 223 cases 217 (97.3%) were performed for an enhancing renal mass. RESULTS: Mean tumor size was 2.6 cm (range 1 to 10) and 95.4% of patients had a normal contralateral kidney. Transient vascular control was performed in 75.1% of cases. Mean operative time (186 minutes) decreased with surgeon experience (p = 0.003) but was independent of tumor size (p = 0.964). Mean warm ischemia time (27.6 minutes) depended on tumor size (p = 0.005) but not on experience (0.964). Mean blood loss was 385 cc and the perioperative transfusion rate was 6.9%. Postoperative complications occurred in 23 cases (10.6%) with the most common being ileus (1.8%), bleeding (1.8%) and urinary leakage (1.4%). Although the mean serum creatinine change after LPN was a function of tumor size (p <0.001), it was clinically insignificant (0.13 mg/dl). No significant relationship was observed between warm ischemia time and creatinine change (p = 0.262). The final pathological evaluation revealed renal cell carcinoma in 144 patients (66.4%) and the overall positive margin rate was 3.5%. Only 2 renal cell carcinoma recurrences in the operated kidney (1.4%) were identified (mean followup +/- SD 24 +/- 12 months). CONCLUSIONS: LPN is an effective approach for treating small renal masses with low perioperative morbidity. Contrary to previous reports, more than 30% of the enhancing renal lesions excised in this series were found to be benign on final pathological evaluation.

Adult↗
PubMed2005

Adrenal myelolipoma.

Explore the source record for details and available documents.

Adrenal Gland Neoplasms↗
PubMed2005

Percutaneous radio frequency ablation of renal masses: results at a 2-year mean followup.

PURPOSE: We describe our experience with and results of percutaneous computerized tomography guided radio frequency ablation (RFA) for small (less than 4 cm) renal tumors at a 2-year mean followup. MATERIALS AND METHODS: A total of 49 patients (60 renal tumors) with a mean age of 63.9 years underwent percutaneous RFA. Indications for RFA were severe comorbidities or previous abdominal surgery precluding operative management, or hereditary conditions predisposing to multiple tumor recurrence. Persistent enhancement on initial followup imaging was considered incomplete treatment and all such patients underwent biopsy and were offered repeat RFA. Enhancement or enlargement on subsequent imaging was considered tumor recurrence and these patients were counseled regarding further therapy. RESULTS: Three patients (4 tumors) were excluded from evaluation due to death from unrelated causes or loss to followup. A total of 46 patients (56 tumors) were available for evaluation at a mean followup of 27.5 months (range 12 to 48). Six tumors were incompletely treated with the first RFA and successfully treated with a second session. Recurrences after successful initial treatment were seen in 3 of 46 patients. These recurrences developed 24, 25 and 31 months following RFA, respectively, and all occurred in patients with a central tumor of 3.0 cm or greater. Overall local control was achieved in 94.6% of tumors (53 of 56). CONCLUSIONS: RFA is an emerging alternative treatment modality for small renal tumors. Larger (greater than 3.0 cm) central tumors represent unique technical challenges, making these tumors more prone to recurrence. Long-term followup is needed to establish the oncological durability of this technique.

Adult↗
PubMed2005

Laparoscopic renal-adrenal surgery in patients on oral anticoagulant therapy.

PURPOSE: Patients requiring chronic anticoagulation are theoretically at increased risk for hemorrhage or thromboembolism perioperatively. Experience with laparoscopic renal/adrenal surgery in patients on chronic warfarin is limited. We assessed hemorrhagic/thromboembolic complications in this group of patients. MATERIALS AND METHODS: The records of 787 patients undergoing laparoscopic renal/adrenal surgery were retrospectively reviewed. A total of 25 patients on chronic oral anticoagulation with warfarin were identified. The indications for warfarin therapy as well as perioperative management were reviewed. Clinical parameters, including operative time, estimated blood loss, hemorrhagic/thromboembolic complications and transfusions, were documented and compared with those in patients not receiving chronic anticoagulation. RESULTS: Atrial fibrillation (56% of cases) and a prosthetic mitral valve (28%) were the most frequent indications for chronic anticoagulation. Bridging anticoagulation with unfractionated heparin was the most frequent management method (68% of cases). Patients with anticoagulation were older (p <0.001) and hospitalized longer (<0.001) than those without anticoagulation. Operative time, estimated blood loss and the conversion rate were not significantly different between the groups. However patients on chronic warfarin significantly more often required transfusion (24% vs 5.2%, p <0.005) and had more postoperative bleeding episodes (8% vs 0.9%, p <0.05) than patients not on chronic anticoagulation. No thromboembolic events occurred in the anticoagulated group, while 3 occurred in the nonanticoagulated group (p = 1). CONCLUSIONS: Laparoscopic renal/adrenal surgery in patients requiring chronic anticoagulation therapy can be performed safely. The risk of intraoperative bleeding is not increased, although the incidence of postoperative bleeding as well as transfusions is higher.

Administration, Oral↗
PubMed2005

Long-term survival analysis after laparoscopic radical nephrectomy.

PURPOSE: This report assesses the long-term oncological efficacy of laparoscopic radical nephrectomy compared with open radical nephrectomy in patients with clinically localized renal cell carcinoma. MATERIALS AND METHODS: We analyzed the data from 121 patients who underwent radical nephrectomy between 1991 and 1999 for clinical tumor stage T1/2 N0M0. The medical records of all patients were retrospectively reviewed with emphasis on tumor recurrence and survival. Statistical comparison was performed using Kaplan-Meier analysis. RESULTS: The median followup was 73 months for the laparoscopic group and 80 months for the open group. Of the 67 patients who underwent laparoscopic surgery, 53 survived without any recurrence of disease, 2 are currently alive with metastasis, 2 died of metastatic disease in months 12 and 17, and 10 patients died without any disease recurrence. Laparoscopic port site metastasis did not develop in any patients. Of the 54 who underwent open surgery, 34 survived without any recurrence of disease, 1 currently has metastasis, 6 died of metastasis within 17 to 74 months, and 13 died without any disease recurrence. A comparison of the 5 and 10-year disease-free survival rates of the laparoscopic and open groups revealed no significant differences. In addition, the 5 and 10-year cancer specific and actuarial survival rates were not significantly different. CONCLUSIONS: Based on long-term followup, our evaluation confirmed for clinical tumor stage T1/2 N0M0 that laparoscopic radical nephrectomy is oncologically equivalent to open radical nephrectomy.

Carcinoma, Renal Cell↗