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European Urology | 1999

Early Prostate-Specific Antigen Relapse after Radical Retropubic Prostatectomy:Prediction on the Basis of Preoperative andPostoperative Tumor Characteristics

Markus Graefen; Joachim Noldus; Uwe Pichlmeier; Alexander Haese; Peter Hammerer; Salvador Fernandez; Stefan Conrad; Rolf-Peter Henke; Edith Huland; Hartwig Huland

Objectives: This study was undertaken to distinguish between patients who will and will not benefit from a retropubic radical prostatectomy (RRP) for clinically localized prostatic carcinoma (PCa) on the basis of preoperative and postoperative tumor characteristics. Methods: Data of 318 consecutive patients who underwent RRP for clinically localized PCa were reviewed. Preoperative characteristics used included clinical stage, findings on transrectal ultrasonography, prostate-specific antigen (PSA) values, Gleason grade, number of positive biopsies, number of biopsies containing any Gleason grade 4 and/or 5 cancer, and number of biopsies with predominant (>50% of cancerous tissue) Gleason grade 4 and/or 5 cancer. Postoperative characteristics included pathologic stage, Gleason grade, margin status, cancer volume, and volume of Gleason grade 4 and/or 5 cancer. The impact on biochemical relapse after RRP were calculated by Cox regression and CART (classification and regression tree) analysis to establish low, intermediate, and high risk of recurrence. Results: Of patients who underwent RRP, 66% showed no evidence of relapse after a follow-up of 42 months. All preoperative and postoperative characteristics showed a significant association with biochemical relapse. Cox regression of preoperative characteristics showed the number of positive biopsies with predominant Gleason grade 4 and/or 5 cancer to be the most accurate predictor of failure (p < 0.0001), followed by the number of positive biopsies and PSA. CART analysis distinguished between four risk groups on the basis of the same characteristics as in the Cox regression. The low-risk group consisted of 232 patients (75.1%) and the high-risk group of 17 patients (5.5%); corresponding Kaplan-Meier curves showed a 2-year PSA-free survival rate of 97% for the low-risk group and 20% for the high-risk group. Cox regression of postoperative characteristics recognized the volume of Gleason grade 4 and/or 5 as the characteristic with the strongest association with biochemical failure. CART analysis distinguished between four risk groups, using the volume of high-grade cancer as the most influential characteristic. The corresponding Kaplan-Meier curves showed for the low-risk group (n = 79; 29.6%) a PSA-free survival rate of 96% after 42 months and for the high-risk group (n = 47; 17.6%) a 21% PSA-free survival rate after 42 months. Conclusion: For preoperative and postoperative estimation of biochemical recurrence after RRP, a quantitative analysis of high-grade cancer, expressed by the number of preoperative biopsy cores containing high-grade cancer and the volume of cancer, proved to be the best predictor of relapse. CART analysis might be useful in advising patients for their best therapy options. However, defined characteristics of risk groups should be evaluated with new prospective data before they are used routinely.


The Journal of Urology | 1998

SYSTEMATIC SEXTANT BIOPSIES IMPROVE PREOPERATIVE PREDICTION OF PELVIC LYMPH NODE METASTASES IN PATIENTS WITH CLINICALLY LOCALIZED PROSTATIC CARCINOMA

Stefan Conrad; Markus Graefen; Uwe Pichlmeier; Rolf-Peter Henke; Peter Hammerer; Hartwig Huland

PURPOSE An algorithm including the results of systematic sextant biopsies was statistically developed and evaluated to predict the probability of pelvic lymph node metastases in patients with clinically localized carcinoma of the prostate. MATERIALS AND METHODS Clinical stage, serum prostate specific antigen concentration, Gleason score, number of positive biopsies, number of biopsies containing any Gleason grade 4 or 5 cancer and number of biopsies predominated by Gleason grade 4 or 5 cancer were recorded in 345 patients undergoing pelvic lymph node dissection and correlated with the incidence of lymph node metastases. Multivariate logistic regression, and classification and regression trees analyses were performed. RESULTS In univariate analysis all variables had a statistically significant influence on lymph node status. Logistic regression showed that the amount and distribution of undifferentiated Gleason grade 4 and 5 cancer in the biopsies were the best predictors of lymphatic spread followed by serum prostate specific antigen. Classification and regression trees analysis classified 79.9% of patients who had 3 or fewer biopsies with Gleason grade 4 or 5 cancer and no biopsies predominated by undifferentiated cancer as a low risk group. In this group positive lymph nodes occurred in only 2.2% (95% confidence interval 0.8 to 4.7%). CONCLUSIONS Including the results of systematic sextant biopsies substantially enhances the predictive accuracy of algorithms that define the probability of lymph node metastases in prostatic cancer. Patients thus defined as having no lymphatic spread could potentially be spared pelvic lymph node dissection before definitive local treatment.


The Journal of Urology | 2002

PROSPECTIVE VALIDATION OF AN ALGORITHM WITH SYSTEMATIC SEXTANT BIOPSY TO PREDICT PELVIC LYMPH NODE METASTASIS IN PATIENTS WITH CLINICALLY LOCALIZED PROSTATIC CARCINOMA

Stefan Conrad; Markus Graefen; Uwe Pichlmeier; Rolf-Peter Henke; Andreas Erbersdobler; Peter Hammerer; Hartwig Huland

PURPOSE We prospectively validate an algorithm to predict pelvic lymph node metastasis in patients with clinically localized prostatic carcinoma. MATERIAL AND METHODS A total of 293 patients with prostatic cancer were identified before pelvic lymph node dissection according to an algorithm developed with the classification and regression tree analysis as high-greater than 3 sextant biopsies containing any Gleason grade 4 or 5 cancer, intermediate-at least 1 biopsy dominated by Gleason grade 4 or 5 cancer but not high risk and low risk-all other patients. Observed and predicted frequencies of pelvic lymph node metastasis were compared. RESULTS The observed frequencies of lymph node metastasis were remarkably similar to the predicted frequencies, including 2.8% versus 2.2% in 85.7% of patients in the low risk group, 16.7% versus 19.4% in 10.2% intermediate and 41.7% versus 45.5% in 4.1% high, respectively. If patients in the low risk group were considered to have node negative disease the specificity and negative predictive value of the algorithm were 88.4% and 97.2%, respectively. CONCLUSIONS Our algorithm is valid as a simple and accurate tool for the prediction of pelvic lymph node metastasis in patients with clinically localized prostatic cancer. Those 85.7% of patients classified by the algorithm to have a low risk of lymphatic spread should not undergo pelvic lymph node dissection before definitive local treatment.


European Urology | 2001

Frequent p16/MTS1 Inactivation in Early Stages of Urothelial Carcinoma of the Bladder Is Not Associated with Tumor Recurrence

Martin G. Friedrich; Constanze Blind; Karin Milde-Langosch; Andreas Erbersdobler; Stefan Conrad; Thomas Löning; Peter Hammerer; Hartwig Huland

Objective: p16, located at chromosome 9p21, is a negative regulator of G1 cell checkpoint and functions as tumor suppressor gene. Only few data are available on the frequency and clinical relevance of p16 alterations in Ta, T1 transitional cell carcinoma (TCC) of the bladder. We investigated 40 patients with Ta, T1 TCC of the bladder for p16 alterations (mutations, homozygote deletions, allelic loss) or reduced p16 immunoreaction. Patients and Methods: DNA was prepared from microdissected tumor tissue from 40 patients with pTa, pT1 TCC of the bladder (pTa: 18 patients; pT1: 22 patients; grade 1: 7 patients; grade 2: 28 patients; grade 3: 5 patients). Mutation screening was performed using polymerase chain reaction (PCR), single–strand conformation polymorphism (SSCP) and direct sequencing at exon 1 and exon 2. Detection of homozygote deletions was performed using multiplex PCR. Immunohistochemistry (IHC) was performed using an anti–human monoclonal antibody (p16, Pharmingen). Allelic loss was detected by PCR using three different microsatellite markers (D9S161, D9S171, D9S319). Results: SSCP and direct sequencing revealed 3 cases of base substitution which turned out to be natural polymorphisms. Homozygote deletions were not detected in any case. p16 IHC revealed reduced p16 expression (<5% positive nuclei) in 10 patients; 30 patients had a positive reaction (≧5% positive nuclei) and 10 patients a strong positive reaction (≧50% positive nuclei). Thirteen of 37 informative cases revealed loss of heterozygosity (LOH) with at least one marker. After a median follow–up of 23 months, 15 patients suffered from disease recurrence. Statistical analysis using Kaplan–Meier analysis and the log–rank test did not reveal significant association of recurrence–free interval and detection of LOH (p = 0.34) or p16 IHC (p = 0.9). Conclusions: We present a comprehensive evaluation of chromosome 9p21 alterations including p16 analysis and clinical follow–up data. Although p16 mutations and homozygote deletions are rarely detectable in Ta, T1 TCC, the reduction of p16 expression and the frequent hemizygote deletions at 9p21 suggest an early involvement of chromosome 9p and p16 in superficial TCC.


The Journal of Urology | 1991

The Cold-Knife Technique for Endourological Management of Stenoses in the Upper Urinary Tract

Andreas W. Schneider; Stefan Conrad; R. Busch; U. Otto

Between 1985 and October 1989 we managed 13 patients with primary and 43 with secondary obstruction of the upper urinary tract with the endourological cold-knife technique. We treated 26 patients with stenosis of the ureteropelvic junction, 9 with infundibular stenosis, 12 with ureteral obstruction after inflammation or radiation therapy, 7 with stricture of the ureter in kidney transplants and 2 with stenosis of the ureter after ureterosigmoidostomy. Endourological management was successful in 42 of 56 cases with a decrease or total elimination of obstruction. Stenosis recurred in 9 patients. Our results indicate that the cold-knife technique should be attempted as the initial approach in all cases of primary or secondary obstruction of the upper urinary tract.


The Journal of Urology | 2002

Clinical use of Urinary Markers For The Detection And Prognosis Of Bladder Carcinoma: A Comparison Of Immunocytology With Monoclonal Antibodies Against Lewis X And 486p3/12 With The BTA STAT And NMP22 Tests

Martin G. Friedrich; Angelika Hellstern; Stefan Hautmann; Markus Graefen; Stefan Conrad; E. Huland; Hartwig Huland

PURPOSE The noninvasive detection of urothelial carcinoma remains challenging. We prospectively evaluated urine markers for bladder carcinoma. We compared the NMP22 (Matritech, Cambridge, Massachusetts) and BTA Stat (Bard Diagnostics, Redmond, Washington) tests with immunocytology using mAbs 486p3/12 and BG7 against Lewis X antigen. MATERIALS AND METHODS The NMP22 and BTA Stat tests were performed in urine samples and immunocytology with mAbs 486p3/12 and BG7 staining were performed in bladder washing specimens in 146 samples of 115 patients undergoing transurethral resection for suspected bladder carcinoma (70) or 45 undergoing followup cystoscopy for a history of bladder carcinoma (76). Bladder carcinoma was detected in 54 patients, including stages pTa in 25, pT1 in 20, pT2 in 8 and carcinoma in situ in 1, while 61 had no evidence of bladder carcinoma. The cutoff was 10 units per ml. for the NMP22, 30% positive cells for 486p3/12 and 5% positive cells for the Lewis X tests. RESULTS BTA Stat was positive in 65 samples (44.5%) and NMP22 was positive in 69 (47.3%). Immunocytology with mAbs 486p3/12 and BG7 against Lewis X was positive in 52 (35.6%) and 109 (74.7%) samples, respectively. Sensitivity was 70.3% for BTA Stat, 68.5% for NMP22, 68.5% for 486p3/12 and 94.4% for Lewis X. Specificity was 70.6% for BTA Stat, 65.2% for NMP22, 83.6% for 486p3/12 and 36.9% for Lewis X. Area under the receiver operating characteristics curve was 0.6804 for NMP22, 0.7226 for Lewis X and 0.8002 for 486p3/12. False-positive results on BTA Stat in 2 of 22 patients (9%), on NMP22 in 2 of 25 (8%), on 486p3/12 in 3 of 11 (27%) and on Lewis X in 4 of 43 (9.3%) were associated with tumor recurrence. Furthermore, negative results on BTA Stat in 2 of 39 patients (2%), on NMP22 in 2 of 36 (0.5%), on Lewis X in 0 of 18 (0%) and on 486p3/12 in 1 of 50 (2%) was associated with tumor recurrence during followup. CONCLUSIONS Immunocytology with mAbs against Lewis X showed higher sensitivity than all commercially available tests evaluated. Because of its high sensitivity and high negative predictive value, it may be useful for screening in a high risk population. Patients with a false-positive 486p3/12 test results are at increased risk for tumor recurrence compared with those with negative results.


The Journal of Urology | 2000

Detection rate of histologically insignificant prostate cancer with systematic sextant biopsies and fine needle aspiration cytology.

Stefan Hautmann; Stefan Conrad; Rolf Peter Henke; Andreas Erbersdobler; Jörg Simon; Michael Straub; Markus Graefen; Hartwig Huland

PURPOSE We evaluate the detection rate of insignificant prostate cancer and the rate of significant prostate cancer overlooked in the results of systematic sextant biopsy and fine needle aspiration biopsy of the prostate of asymptomatic men with serum prostate specific antigen concentrations less than 4.0 ng./ml. MATERIALS AND METHODS We analyzed specimens from 133 consecutive patients with a mean age of 60 years undergoing cystoprostatectomy for bladder cancer. Six systematic biopsy specimens and 2 fine needle aspiration cytology samples were taken from the prostate immediately after cystoprostatectomy. The specimens were step sectioned and examined for prostate cancer. Insignificant prostate cancer was defined as any cancer with an aggregate volume 0.5 cm.3 or less. RESULTS Incidental prostate cancer was found in 58 of the 133 patients (44%). Tumor volume was 0.5 cm.3 or less in 47 cases. Sextant biopsy detected 7 cancers, including 4 of 47 (9%) that were insignificant and 3 of 11 (27%) that were significant. Fine needle aspiration cytology also detected 7 cancers, including 3 (6%) and 4 (36%) that were insignificant and significant, respectively. CONCLUSIONS Systematic sextant biopsy and fine needle aspiration cytology each diagnose prostate cancer in about 5% of asymptomatic men who have normal digital rectal examination and serum prostate specific antigen less than 4.0 ng./ml. However, many of the cancers thus detected are insignificant and most of the significant cancers are missed. Therefore, routine screening of such patients with sextant biopsy or aspiration cytology does not appear to be justified.


European Urology | 2001

Relevance of p53 Gene Alterations for Tumor Recurrence in Patients with Superficial Transitional Cell Carcinoma of the Bladder

Martin G. Friedrich; Sabine Riethdorf; Andreas Erbersdobler; Christian Tiemer; Hartwig Schwaibold; Jan K. Sölter; E. Huland; Lutz Riethdorf; Stefan Conrad; Peter Hammerer; Hartwig Huland

Purpose: The prognostic relevance of p53 protein accumulation in muscle–invasive bladder carcinoma is well documented, but the prognostic relevance of p53 alterations in superficial bladder tumors remains uncertain. Immunohistochemical data are divergent, possibly because of the use of nonstandardized techniques. We therefore investigated the relevance of p53 gene point mutations and loss of heterozygosity (LOH) for tumor recurrence. The results of this molecular analysis were compared with accumulation of the p53 protein as shown by immunohistochemistry. Material and Methods: Representative tumor tissue was selected and microdissected from 40 patients (pTa, 18 patients; pT1, 22 patients; grade I, 7 patients; grade II, 28 patients; grade III, 5 patients). Polymerase chain reaction (PCR) was carried out with exons 5–8. All PCR products were screened for p53 mutations with temperature–gradient gel electrophoresis (TGGE). When mobility shift was observed, direct nucleotide sequencing was performed. Detection of LOH was performed with nonradioactive microsatellite analysis using three markers (TP 53, D17S513 and D17S786) on chromosome 17p. Immunohistochemistry was performed with the DO 7 antibody. Tumor samples with p53 accumulation of 5% or more positive nuclei were classified as positive. Univariate analysis for disease–free survival was performed using Kaplan–Meier analysis and the log–rank test. Results: TGGE and direct sequencing detected mutations in 10 of 40 patients (2 of 18 pTa and 8 of 22 pT1 patients). LOH was detected in 11 patients. Both a mutation and LOH were detected in 3 patients. p53 immunohistochemistry detected at least 5% positive nuclei in 28 of 40 patients (70%). After a median follow–up of 26 months 14 patients suffered disease recurrence. Whereas disease–free survival did not correlate with a mutation (p = 0.77, log–rank test), LOH (p = 0.2) or a mutation in combination with LOH (p = 0.23), a positive p 53 immunoreaction was significantly associated with short disease–free survival (p = 0.009). Conclusion: Despite the relatively high percentage of patients with p53 gene alteration in this population no significant correlation between the detection of molecular alteration and disease recurrence could be found. We conclude that, in contrast to immunohistochemical accumulation, gene alterations play only a minor role in tumor recurrence of p53 in patients with superficial transitional cell carcinoma of the bladder, and that immunohistochemical accumulation of the p53 protein has to be explained by mechanisms other than gene mutations.


The Journal of Urology | 1994

Endo-Urological Cold-Knife Incision for Ureteral Stenosis after Renal Transplantation

Stefan Conrad; Andreas W. Schneider; Werner Tenschert; Wolf-Hartmut Meyer-Moldenhauer; Hartwig Huland

Cold-knife incision of stenoses in the transplant ureter was performed in 11 patients with upper urinary tract obstruction in renal transplants. The operations were complicated by bleeding in 2 patients and the graft had to be removed in 1 of them. The stenoses could be treated successfully in 10 of the 11 patients (91%) and the mean serum creatinine concentration decreased significantly from 3.4 to 1.8 mg./dl. After a mean of 26 months only 1 obstruction recurred, so the long-term success rate was 82%. Because of the favorable long-term results and the low incidence of complications, we recommend endo-urological cold-knife incision of ureteral stenosis as the first-line treatment for upper urinary tract obstruction in renal transplants.


The Journal of Urology | 2002

URINARY CONCENTRATION AND TISSUE MESSENGER RNA EXPRESSION OF MONOCYTE CHEMOATTRACTANT PROTEIN-1 AS AN INDICATOR OF THE DEGREE OF HYDRONEPHROTIC ATROPHY IN PARTIAL URETERAL OBSTRUCTION

Miriam Stephan; Stefan Conrad; Thilo Eggert; Roman Heuer; Salvador Fernandez; Hartwig Huland

PURPOSE To find a potential prognostic marker of the induction of hydronephrotic atrophy in congenital hydronephrosis we investigated whether the messenger (m)RNA expression and urinary concentration of monocyte chemoattractant protein-1 (MCP-1) correlated with the degree of partial ureteral obstruction, and subsequent hydronephrotic atrophy and interstitial fibrosis. MATERIALS AND METHODS We created left partial ureteral obstruction in 96 juvenile Wistar rats and complete ureteral obstruction in 18, while 16 underwent sham operation. Depending on excretion of contrast medium into the renal pelvis after 3 days we defined 2 degrees of hydronephrosis. Renal mRNA expression of MCP-1, and renal pelvic and bladder urinary concentrations of MCP-1 were measured after 1, 2 and 3 weeks, and compared with the degree of hydronephrotic atrophy. RESULTS Grade 1 partial ureteral obstruction resulted in mild histological changes. Grade 2 partial and complete obstruction resulted in significant hydronephrotic atrophy. MCP-1 mRNA expression in the kidney remained unchanged in grade 1 partial obstruction but was moderately increased in grade 2 partial obstruction and clearly over expressed in complete ureteral obstruction. The renal pelvic urinary concentration of MCP-1 was not higher in rats with grade 1 partial obstruction than in sham operated animals but it was significantly increased in those with grade 2 partial and complete obstruction. CONCLUSIONS mRNA expression and the urinary concentration of MCP-1 correlate with the degree of obstruction and subsequent renal damage in hydronephrosis. They may serve as prognostic markers in children with congenital hydronephrosis.

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