Laparoscopic nephrectomy: the experience of the laparoscopy working group of the German Urologic Association.

PURPOSE: The centers of the laparoscopy working group of the German Urologic Association collected data to prove the efficacy, safety and reproducibility of laparoscopic nephrectomy. MATERIALS AND METHODS: At 14 centers 482 laparoscopic nephrectomies have been performed until December 1996 via a transperitoneal approach in 344 (71%) and a retroperitoneal approach in 138 (29%). All 482 laparoscopic nephrectomies were performed by a total of 20 surgeons with an average of 24 procedures per surgeon (range 4 to 105). The indications for nephrectomy were benign renal pathology in 444 patients (92%), including renovascular disease in 28%, hydronephrosis in 20%, reflux nephropathy in 15%, chronic pyelonephritis in 12%, end stage nephrolithiasis in 11%, renal dysplasia in 4% and renal tuberculosis in 1%. Of the remaining 38 patients (8%) laparoscopic radical nephrectomy was performed for renal cell carcinoma in 5% and for upper tract transitional cell carcinoma in 3%. RESULTS: Operating time depended mainly on the pathology of the kidney (that is small dysplastic organ versus large hydronephrosis) and the learning curve of the surgeon. However, the average operating time did not vary significantly among the different centers (maximum 277.6 and minimum 81.9 minutes). Intraoperative or perioperative complications were noted in 29 patients (6.0%), including bleeding in 22 (4.6%), bowel injury in 3, hypercarbia in 2 and pleura lesion in 1 and pulmonary embolism in 1. The conversion rate was 10.3% (bleeding, bowel injury, difficult dissection), including 4 patients with renal tuberculosis, 2 with xanthogranulomatous nephritis, and 1 each following renal trauma and embolization. The re-intervention rate was 3.4% due to bleeding in 6 cases, abscess formation in 3, intestinal stenosis in 2 and a pancreatic fistula and port hernia in 1. Mean hospital stay was 5.4 days. CONCLUSIONS: Laparoscopic nephrectomy has become a well established procedure in those urology departments focusing on laparoscopy. The indications and results are reproducible at these centers. However, for patients with severe perinephritis (that is renal tuberculosis, xanthogranulomatous nephritis, posttraumatic atrophy) a higher likelihood of open conversion must be considered.

Computed tomography characterization of renal cell tumors in correlation with histopathology.

RATIONALE AND OBJECTIVES: The authors distinguish the histomorphologic subtypes of renal cell tumors (RCTs) by computed tomography (CT). METHODS: In a consensus conference between radiologists, pathologists, and urologists, the CT criteria of the various subtypes of RCTs (clear cell, chromophilic cell, chromophobic cell renal carcinoma and oncocytoma) were established. Computed tomography scans of 65 resected RCTs were reevaluated independently by seven radiologists. Using a numerical scoring system, they first attempted to differentiate clear cell from nonclear cell RCTs. A further attempt then was made to classify each tumor into one of the four categories. RESULTS: The sensitivity for the diagnosis of clear cell RCT was 72.5% (213 of 294 true-positive findings) and 82% (132 of 161 true-positive findings) for the nonclear cell group. For tumors more than 3 cm in diameter the sensitivities were 80.25% for the clear cell group and 80.7% for the nonclear cell group. Specific differentiation into the four subtypes was not possible. Oncocytomas were classified correctly in only 6 of 49 observations (12.2%). CONCLUSIONS: Small clear cell tumors often fail to show the CT characteristics that would permit an accurate classification. In tumors measuring 3 cm or more, differentiation between clear cell and nonclear cell types by means of CT criteria is possible. Nevertheless, as RCTs show a great variation in appearance, a differentiation into subtypes of the nonclear cell RCTs cannot be accomplished by CT. Using a uniform examination protocol and spiral scanning technique, the sensitivity of CT in the diagnosis of the subtypes of RCTs may be able to be further increased. Some tumors, especially oncocytomas, undoubtedly will remain diagnostic dilemmas.

Increased discrimination between benign prostatic hyperplasia and prostate cancer through measurement of percentage free PSA.

OBJECTIVE: The value of Prostate-Specific Antigen (PSA) for the early detection of Prostate Cancer (CaP) is controversial due to an appreciable false positive rate causing unnecessary biopsies. As PSA exits in both free and bound forms the percentage of free PSA was found to be lower in CaP than in Benign Prostatic Hyperplasia (BPH). We investigated whether the percentage of free PSA offers better discrimination on the detection of CaP. MATERIAL AND METHODS: In a retrospective analysis the percentage of free PSA was determined in the sera of 50 consecutive patients with histologically proven BPH (n = 30) and clinically localised CaP without metastases (n = 20; pT1-3 No Mo). Serum levels of free PSA and total PSA were determined employing a chemiluminescent enzyme immunoassay. RESULTS: Patients with CaP demonstrated a lower percentage of free PSA (median: 8.5, range: 2.7-24.5) than patients with BPH (median: 22.35, range: 8.9-66.7). (p < 0.001). CONCLUSION: Determination of percentage of free PSA enhances the discrimination between BPH and CaP and may reduce the number of unnecessary biopsies in patients with elevated PSA.

Metastatic workup of patients with prostate cancer employing skeletal alkaline phosphatase.

PURPOSE: To compare the efficacy of two tests, prostate-specific antigen (PSA) and skeletal alkaline phosphatase (SAP) as staging markers to discriminate patients with cancer of the prostate (CaP) with bony metastases (M1) from those without bony metastases (Mo). MATERIAL AND METHODS: Forty-seven untreated patients with Mo (n = 26) and M1 (n = 21) CaP were entered in this study. Serum concentrations for SAP and PSA were determined using two immunoassays. RESULTS: None of the Mo patients but 65% of the M1 patients exhibited a SAP value above the reference range (< 19 ng/ml). A corresponding cut-offpoint of 100 ng/ml for PSA showed that 27% of Mo patients and only 65% of the M1 patients exhibited a value > 100 ng/ml. This resulted in a sensitivity and specificity of 65% and 100% for SAP and 65% and 73% for PSA. CONCLUSION: Our findings suggest that SAP could become a useful marker in the evaluation of patients with newly diagnosed CaP as it seems to provide additional information concerning the skeletal status of these patients.

[Improved discrimination between prostatic carcinoma and benign prostatic hyperplasia by determination of free prostate-specific antigen percentage]. / Verbesserte Diskriminierung zwischen Prostatakarzinom und benigner Prostatahyperplasie durch die Bestimmung des prozentualen Anteils von freiem prostataspezifischen Antigen.

We investigated whether the free-to-total prostate-specific antigen (PSA) ration (f-PSA/t-PSA ratio; i.e. percentage of free PSA) represents a better discriminator for the detection of cancer of the prostate (CaP). In a retrospective analysis, the percentage of free PSA was determined in the sera of 35 patients with histologically proven benign prostatic hyperplasia (BPH) and 35 patients with clinically localized CaP. Patients with urolithiasis (n = 33) served as a control group. Serum levels of free PSA and total PSA were determined employing a chemiluminescent enzyme immunoassay. Patients with CaP demonstrated a lower percentage of free PSA (median: 8.7) than patients with BPH (median: 20.0; P < 0.001). Determination of the percentage of free PSA enhances the differentiation between BPH and CaP and may reduce the number of unnecessary biopsies in patients with an elevated PSA. Confirmation of our preliminary results is required.

Evaluation of possible tissue damage in patients undergoing extracorporeal shock wave lithotripsy employing C-reactive protein.

Extracorporeal shock wave lithotripsy (ESWL) has become the most common treatment for stones in the upper urinary tract. Tissue injury related to ESWL has been documented. C-reactive protein (CRP) is the classical acute-phase protein most recognized as an early marker in diseases characterized by inflammation and tissue injury. Possible tissue trauma by ESWL was evaluated by serial CRP determinations in 150 patients with kidney stones, whose follow-up was uneventful. The mean CRP-concentration prior to ESWL was 6.34 mg/l. The majority of patients did not show any further elevation of CRP-levels. Mean CRP-levels were 7.62 mg/l on the first, 6.12 mg/l on the third and 5.09 mg/l on the fifth day after ESWL. No correlation was observed between the number of shock waves and CRP levels. Judged by CRP-determinations tissue damage induced by ESWL can be considered to be minimal as no marked CRP-elevations could be observed in patients with an uneventful follow-up after ESWL.

Detection of circulating prostatic cells during radical prostatectomy.

The detection of micrometastasis of prostate cancer could help to decide more appropriate therapeutic strategies in an individual patient. We have developed a flow cytometric method for detecting cytokeratin-positive cells in the peripheral blood before, during and after radical prostatectomy in patients with prostatic carcinoma. By means of this technique we were able to detect a higher number of cytokeratin-positive cells in the intraoperative blood sample than in the pre- and postoperative blood sample in 15 patients with prostate cancer (P < 0.05). Our results show an increase in the number of cytokeratin-positive cells with increasing tumor stage and grade, as well a good correlation of prostate-specific antigen (PSA) value with the number of cytokeratin-positive cells (r > 0.6). Our results underline the importance of no-touch techniques at prostatectomy to minimize release of tumor cells into the circulation during surgery. In the light of our results we consider that the indication for cell savers during radical prostatectomy should be reevaluated. The possibility of detecting single metastatic cells in peripheral blood will enable better individual patient management, and open up new modalities for diagnosing early prostate cancer and enhancing patient monitoring in relapse and tumor progression.

Diagnostic and therapeutic laparoscopy of the nonpalpable testis.

We report about laparoscopic examination and treatment of 19 patients with 25 non-palpable testes. Thirteen patients presented with unilateral and six patients with bilateral absent testes, respectively. In all cases of non-palpable testes laparoscopy was able to determine the exact localization and supported the surgical approach. Six testicles were treated by open orchiectomy after diagnostic laparoscopy; three testes were fixed by laparoscopically assisted orchiopexy. Three patients (three testicles) were treated by standard orchiopexy after laparoscopy and in three cases microvascular autotransplantation was performed. Laparoscopically, five aplastic testicles without vas and vessels were diagnosed. Three testes were considered as vanishing and in two patients (two testes) due to previous surgical exploration elsewhere testicular remnants were totally atrophic and were resected with the adjacent vas. All laparoscopic findings except the vanishing testis syndrome were proven either by open surgery or by laparoscopic preparation of the internal inguinal ring.

Early detection of infected ureteral obstruction after SWL employing C-reactive protein.

Infection of the obstructed upper urinary tract is a severe complication of stone disease. Early detection and therapy is crucial to prevent septicemia. The authors investigated prospectively whether C-reactive protein (CRP) might act as a marker for the early detection of infected upper urinary tract obstruction. The serum concentration of CRP was compared with the classic markers of inflammation--white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and temperature--in the follow-up of 85 patients undergoing 173 extracorporeal shockwave lithotripsy (SWL) treatments. Post-SWL, 69% of the patients showed dilation of the upper tract on ultrasonography and 16.5% became symptomatic and required intervention. In this group, the mean CRP value was increased 18-fold, whereas the WBC count, ESR, and temperature were not markedly raised. In contrast, patients with no need for additional treatment showed no more than a 2-fold increase in CRP. C-Reactive protein seems to be a useful indicator for the early detection of infected upper urinary tract obstruction.

Laparoscopic ureterolysis in retroperitoneal fibrosis.

We reported on 5 patients with retroperitoneal fibrosis with dilatation of the upper urinary tract. All patients were operated on laparoscopically. Surgery consisted of complete ascending ureterolysis from the pelvis up to the renal pelvis, biopsy of periureteral tissue, intraperitonealisation and/or preparing an omental flap to separate the ureters from the retroperitoneal vessels. Operating time was reduced from 4 hours in a unilateral case down to 5 hours in a bilateral case by performing three-dimensional video endoscopy. In case of Ormond's disease postoperative immunosuppressive medication was given. Ureterolysis in Ormond's disease is a rare but reasonable indication for reconstructive laparoscopic surgery. Both ureters are accessible in full length either transperitoneal or retroperitoneal. Provided all goals of open surgery can be achieved by the laparoscopic technique, patients will benefit from the minimal access.

[Laparoscopic lymphadenectomy in prostate carcinoma. Experiences with 120 patients]. / Laparoskopische Lymphadenektomie beim Prostatakarzinom. Erfahrungen bei 120 Patienten.

Laparoscopic pelvic lymph node dissection was performed in 120 patients scheduled to undergo either radical perineal prostatectomy or radiation therapy. On average 13 lymph nodes were resected in each patient, and 21 patients were found to have metastatic disease in 1-9 lymph nodes. After an initial learning curve, mean operative time was reduced significantly, allowing laparoscopic lymph node dissection and radical prostatectomy to be performed as a one-stage procedure. The overall complication rate was 10%; open revisions were necessary in only 2 of 120 patients. Postoperative hospital stay was 2 days in patients undergoing laparoscopic lymph node dissection only. This minimally invasive procedure is particularly beneficial to patients with lymph node metastases not undergoing radical prostatectomy, as well as to patients planned to be treated by radiation therapy. The combination of laparoscopic lymph node dissection and radical perineal prostatectomy avoids an abdominal incision and thus shortens both the hospital stay and the period of convalescence.

Laparoscopical marsupialization of symptomatic post-transplant lymphoceles.

Post-transplant lymphoceles after kidney transplantations occur with an incidence between 2 and 15%. In the last two years we observed four patients with symptomatic lymphoceles. After an infection or urinoma had been ruled out all cases were operated on laparascopically. All goals of open surgery in lymphoceles were achieved by this minimally invasive technique within an operating time between 40 and 70 min. No complications or recurrences occurred during a mean follow-up period of 17.8 months. Symptomatic post-transplant lymphocele is a rare event and represents an ideal indication for laparoscopic marsupialization.

Prostate-specific antigen: insufficient discrimination between benign prostatic hyperplasia and organ-confined prostate cancer.

OBJECTIVE: Discrimination of patients with benign prostatic hyperplasia (BPH) from those with cancer of the prostate (CaP) is crucial to the management of these diseases. At present, a number of new treatment modalities for symptomatic BPH, which include various nonsurgical treatment modalities, are being discussed. Prior to treatment, it is important to exclude those patients with CaP. In the present study we examined retrospectively the serum prostatic-specific-antigen (PSA) values in both patient groups in order to determine whether serum PSA identifies those patients harboring organ-confined CaP. PATIENTS AND METHODS: Group 1 consisted of 121 patients with histologically confirmed BPH as determined from pathological analysis of the surgically removed specimens. Group 2 included 69 patients with organ-confined CaP, confirmed pathologically from the analysis of the radical prostatectomy specimens. PSA serum concentration was analyzed in both groups. RESULTS: The median PSA level was 3.96 ng/ml (range: 0.5-31.2 ng/ml) in the BPH group and 7.8 ng/ml (range: 0.7-37.7 ng/ml) in the CaP group. In spite of a statistically significant difference (p = 0.0001), serum PSA values overlapped considerably in both groups. CONCLUSIONS: Serum PSA demonstrated only a limited ability to discriminate between BPH and organ-confined CaP. Therefore some patients with symptomatic BPH undergoing nonsurgical treatment may harbor clinically significant CaP despite "normal' serum PSA values. Furthermore, PSA-based screening may overlook a significant percentage of patients in whom a rectal digital examination would detect CaP.

Clinical use of prostate-specific antigen and prostate-specific antigen density in the staging of patients with cancer of the prostate.

OBJECTIVE: To examine the efficacy of prostate-specific antigen (PSA) and prostate-specific antigen density (PSAD) in staging patients undergoing radical prostatectomy for clinically localized prostate cancer (CaP). PATIENTS AND METHODS: Prostate gland volumes were estimated in patients with clinically localized CaP (n = 119) performing transrectal ultrasound and employing the prolate ellipse formula. PSA was determined using an enzyme immunoassay. All patients underwent laparoscopic pelvic lymphadenectomy followed by radical perineal prostatectomy in No disease. The PSA density was calculated relating the Serum PSA to the sonographically estimated prostate volume. RESULTS: The pathological examination of the prostatectomy specimens revealed a pT2 tumor in 52 cases (43.7%) and a pT3 tumor in 41 cases (34.5%). In 26 patients (21.8%) the histological examination demonstrated metastases to the lymph nodes. Patients with a pT2No CaP demonstrated a median PSA level of 8.95 ng/ml and a median PSAD of 0.3, those with a pT3No CaP demonstrated a median PSA level of 12.3 ng/ml and a median PSAD of 0.38 and those with a T2-3pN + revealed a median PSA level of 22.9 ng/ml and a median PSAD of 0.7. CONCLUSIONS: Both marker, serum PSA as well as PSAD, did not sufficiently distinguish patients with organ-confined cancer from those with extracapsular tumor extension. In contrast, PSAD levels seem to provide useful additional information in the staging of patients with clinically localized CaP with regard to the lymph node status.

Skeletal alkaline phosphatase in the metastatic workup of patients with prostate cancer.

OBJECTIVE: To compare the efficacy of two tests, prostate-specific antigen (PSA) and skeletal alkaline phosphatase (SAP) as staging markers to discriminate patients with cancer of the prostate (CaP) with bone metastases (M+) from those without bone metastases (M0). METHODS: Thirty-nine untreated patients with CaP M0 (n = 22) and CaP M+ (n = 17) along with 10 patients with benign prostatic hyperplasia, who served as controls, were entered in this study. Serum concentrations for SAP and PSA were determined using two immunoassays. Receiver operating characteristic (ROC) curves were constructed to compare the ability of SAP and PSA to discriminate patients with CaP M+ from CaP M0. RESULTS: None of the M0 patients but 65% of the M+ patients exhibited an SAP value above the reference range (< 19 ng/ml). A corresponding cutoff point of 100 ng/ml for PSA demonstrated that 27% of M0 patients and only 65% of the M+ patients exhibited a value > 100 ng/ml. This resulted in a sensitivity of 65% for both markers. However, SAP revealed a higher specificity than PSA (100 vs. 73%). The ROC curve comparing SAP and PSA demonstrated the superiority of SAP as a marker for bone metastases. CONCLUSION: Our findings suggest that SAP could become a useful marker in the evaluation of patients with newly diagnosed CaP as it seems to provide additional information concerning the skeletal status of these patients.

Laparoscopic bilateral ureterolysis in Ormond's disease.

We report a case of retroperitoneal fibrosis with dilation of the upper urinary tract on both sides and impaired renal function in a 66-year-old female. The patient was successfully treated by laparoscopic ureterolysis and intraperitonealization of both ureters with subsequent immunosuppressive medication. Due to intraoperative subcutaneous emphysema, surgical therapy had to be performed as a two-step procedure but postoperative morbidity was minimal with quick recovery. Laparoscopic ureterolysis is a reconstructive procedure and the ureters are accessible in full length either transperitoneally or retroperitoneally.

The influence of LCD shutter glasses on spatial perception in stereoscopic visualization.

For a general establishment of stereoscopic visualisation systems in clinical routine a fundamental analysis of the influence of technical, optical and physiological parameters onto visual spatial perception seems to be necessary to achieve an optimisation of the existing devices. As one important component of these systems we perform studies on the influence of LCD Shutter glasses on the individual binocular perception. The developed shutter system, the initial experiments and their results are presented.

Using human factor analysis and VR simulation techniques for the optimization of the surgical worksystem.

The introduction of minimal invasive operating techniques into the conventional surgical worksystem, requires a fundamental analysis of the resulting problems. Based on ergonomic investigations, concerning working postures, static holding work and task sequence analysis, bottlenecks of workplace design can be demonstrated. As a contribution to the optimization of workplace design, the development of a CAD-based VR simulation environment with an integrated anthropometric man-model, as a very useful tool for anthropometric system design is presented.

Three-dimensional versus two-dimensional video endoscopy. A clinical field study in laparoscopic application.

Stereoscopic visualisation systems are available for the medical application in clinical routine, especially in the field of endoscopic or minimal invasive surgery. As we have shown in laboratory studies in 1991 the use of stereoscopic visualisation systems leads to a significant improvement of endoscopic manipulation. A broader diffusion of these systems in clinical routine will be based on quantitative evaluation of the influence of stereoscopic visualisation systems on the intervention. As a first approach we performed a clinical field study to compare 2D and 3D video endoscopy in laparoscopic interventions in urological surgery.