A Swoboda

University Hospital Essen, Essen, North Rhine-Westphalia, Germany

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Publications (10)23.68 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Zusammenfassung Hintergrund Studienziel war die Verbesserung der Fallfindungsrate des Prostatakarzinoms mit unauffälligem Tastbefund im PSA-Bereich von 4–10 ng/ml durch die Vernetzung von tPSA, f/tPSA-Ratio, Prostatavolumen, PSA-Dichte, Patientenalter und transrektalem Ultraschallbefund. Methoden Bei 619 Patienten im Altersbereich von 45 bis 75 Jahren mit unauffälligem Tastbefund und PSA-Werten von 4–10 ng/ml wurde eine Sextantenbiopsie der Prostata durchgeführt. Bei allen Patienten wurde die f/tPSA-Ratio (freies PSA zum Gesamt-PSA) bestimmt, eine transrektale Ultraschalluntersuchung durchgeführt, das Prostatavolumen ermittelt und die PSA-Dichte berechnet. Mit Hilfe der logistischen Regression wurden die Abhängigkeit der einzelnen Prüfgrößen und deren Kombination von dem Ergebnis der Histologie überprüft. Ergebnisse Bei 131 der 619 Patienten wurde in der Stanzbiopsie ein Prostatakarzinom gefunden. Die Analyse der genannten Prüfgrößen durch die logistische Regression zeigt, dass die Prüfgrößen Prostatavolumen, Ultraschallbefund und tPSA innerhalb von 4–10 ng/ml nicht zu einer Verbesserung der Fallfindung führen. Die Kombination der Parameter f/tPSA-Ratio, PSA-Dichte und Patientenalter kann die Sensitivität und Spezifität von PSA in der Vorhersage eines Prostatakarzinoms signifikant gegenüber der isolierten Anwendung verbessern. Die ROC-Kurve („receiver operator characteristic“) für die berechnete Karzinomwahrscheinlichkeit schließt eine Fläche von 0,755 ein. Bei einer berechneten Karzinomwahrscheinlichkeit von 5% beträgt die Sensitivität der Fallfindung 97%, die Spezifität liegt bei 35%. In der Praxis können bei einem angenommenen Grenzwert von 5% zur Durchführung einer Stanzbiopsie 31% der Biopsien vermieden werden. In diesem Fall würden nur 3% aller Prostatakarzinome nicht detektiert. Schlussfolgerung Der kombinierte Einsatz von f/tPSA-Ratio, PSA-Dichte und Patientenalter kann im PSA-Bereich von 4–10 ng/ml die Sensitivität der Fallfindung signifikant verbessern.
    Der Urologe 09/2011; DOI:10.1007/s00120-011-2577-8 · 0.44 Impact Factor
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    ABSTRACT: The aim of the study was to improve the case detection rate of prostate cancer for patients who had unremarkable palpation findings and a PSA value in the range of 4 to 10 ng/ml by combination of the parameters total PSA (tPSA), f/tPSA ratio, prostate volume, PSA density, patient's age and transrectal ultrasound findings. Sextant biopsy of the prostate was performed for 619 patients aged 45-75 years who had unremarkable palpation findings and PSA values in the range of 4 to 10 ng/ml. The f/tPSA ratio was determined, transrectal ultrasound examination was performed, the prostate volume was measured and the PSA density calculated. The relationship between the various test variables - and their combination - and the histology results was investigated using logistic regression. Prostate cancer was detected in 131 of 619 patients. Analysis of the aforementioned test variables by means of logistic regression revealed that the combination of the parameters f/tPSA ratio, PSA density and patient's age can significantly increase the sensitivity and specificity of PSA in predicting prostate cancer compared with the use of these parameters on an individual basis. With an assumed limit value of 5% for performance of punch biopsy, 31% of biopsies could be avoided in practice. In such a case, only 3% of instances of prostate cancer would have gone undetected. The combined use of f/tPSA ratio, PSA density and patient's age can significantly enhance the case detection sensitivity for the PSA range of 4 to 10 ng/ml.
    Der Urologe 05/2011; 50(9):1095-100. · 0.44 Impact Factor
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    ABSTRACT: It is common to start with PSA (prostate-specific antigen)-testing at the age of 50. If patients with a PSA value greater than 4 ng/mL should be considered for prostate biopsy, approximately 20% of all men undergoing test are considered for biopsy at the time of first early-detection examination. We have screened 2,592 asymptomatic men younger than 45 years. With a short questionnaire, we assessed age, body mass index (BMI), concomitant diseases, last sexual intercourse, and last bicycle riding. We compared this cohort with a group of 11,656 men aged 45-75 years from a nationwide prostate cancer screening trial. In this cohort, only 4 men with a PSA value greater than 4 ng/mL and 10 with a PSA greater than 3 ng/mL were identified. More than 99% of all men younger than 45 years had a PSA lesser than 4 ng/mL. Sexual intercourse, bicycle riding, or BMI had a significant but minimal influence on the PSA value. It is reasonable to start with PSA testing at the age of 40 years. The advantage of screening younger patients is that almost no one should be considered for biopsy at the time of first early-detection examination. We identified a baseline value at which only a minimal influence was exerted by benign prostatic hypertrophy. In comparison with many current guidelines, we gained a lead time of 10 years for observation of PSA dynamics. The importance of PSA velocity for stratification of patients at risk for development of significant prostate cancer will grow.
    Cancer Epidemiology Biomarkers & Prevention 03/2011; 20(6):1190-5. DOI:10.1158/1055-9965.EPI-10-1198 · 4.32 Impact Factor
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    ABSTRACT: Especially in the setting of total prostate-specific antigen (PSA) in the intermediate range of 4-10 ng/ml and a negative digital rectal examination, the use of the free/total (F/T) PSA ratio has proved to be an effective tool in prostate cancer screening. Whole blood should be analyzed as soon as possible after venipuncture to ensure optimal effectiveness of the F/T PSA ratio. If an immediate serum analysis is not possible, the serum should be frozen or stored at a maximum of 4 degrees C for a short period. Otherwise, when applying the F/T PSA cutoffs as recommended in the literature to a cohort with delayed analysis, a lack of specificity arises, and the initial advantage of reducing biopsies is minimized. To prevent loss of quality in a setting with delayed F/T PSA measurement, we recommend that physicians compare their own data critically with presented results and eventually adapt the cutoffs individually.
    Der Urologe 09/2009; 48(9):1002, 1004, 1006-7. · 0.44 Impact Factor
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    ABSTRACT: Urinary cytology is a non-invasive adjunct to cystoscopy in the diagnosis of bladder cancer. In order to assess the diagnostic accuracy of urinary cytology as an office-based method for clinically relevant high grade (G3) bladder cancer, three nationwide cytology survey tests were performed. Urine specimens from seven patients, three patients with high grade (G3) bladder cancer and four patients with urinary tract infections, were collected. A total of 1,000 cytology slides were produced from each urine specimen. Each set contained five slides (two malignant, three benign) which were sent to all participating German urologists. Three nationwide tests were performed from 1998-2000. The specimen sets were kept the same for the first and second test and in the third test two new slides were introduced. In addition to validity, the reliability was calculated for the first and second test as interobserver and intraobserver reliability according to Cohen's kappa statistics. Due to the change of two specimens in the third test in 2000 only sensitivity and specificity were calculated. A total of 335 urologists took part in the first survey test, 329 in the second and 292 in the third The sensitivity for G3 cytologies was 81.34% in the first, 87.08% in the second and 85.1% in the third survey test and the specificity was 85.87%, 83.58% and 89.15%, respectively. Interobserver reliability showed a weighted kappa value of 0.58 for the first and 0.59 for the second survey test. Calculation of intraobserver reliability was possible for 169 urologists taking part in the first and second survey test and showed a mean kappa value of 0.62. The results of the three nationwide urinary cytology tests indicate that urinary cytology has a high sensitivity in the detection of clinically relevant high grade bladder cancer. The kappa values achieved demonstrate a clear agreement of cytological diagnoses.
    Der Urologe 09/2009; 48(9):1018, 1020-2, 1024. · 0.44 Impact Factor
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    ABSTRACT: Die Urinzytologie ist ein nichtinvasives Instrument zur Charakterisierung von Urothelkarzinomen der ableitenden Harnwege. Um die Genauigkeit der Urinzytologie für klinisch relevante High-grade- (G3-)Harnblasenkarzinome einzuschätzen, wurden 3 bundesweite Zytologieringversuche durchgeführt. Urinproben von 7Patienten, 3Patienten mit High-grade-Harnblasenkarzinomen und 4Patienten mit Harnweginfektionen (HWI) wurden asserviert. Aus jeder gewonnenen Urinprobe wurden 1000 Zytologieobjektträger hergestellt. Sets aus 5 Objektträgern mit jeweils 2 malignen und 3 benignen Urinzytologien wurden an alle teilnehmenden Urologen versand. Drei Ringversuche wurden zwischen 1998 und 2000 durchgeführt. Die Proben der ersten beiden Ringversuche waren identisch. Im III. Ringeversuch wurden 2 neue Präparate eingesetzt. Neben der Validität wurde mittels Cohens Kappa-Statistik für die ersten beiden Ringversuche die Reliabilität als Inter- und Intraobserver-Reliabilität berechnet. Aufgrund des Probenaustausches wurden für den III. Ringversuch nur die Spezifität und Sensitivität bestimmt. 335 niedergelassene Urologen nahmen am I., 329 am II. und 292 am III. Ringversuch teil. Die Sensitivität für G3-High-grade-Zytologien betrug 81,34% im I., 87,08% im II. und 85,1% im III. Ringversuch, die Spezifität lag bei jeweils 85,87%, 83,58% und 89,15%. Die Interobserver-Reliabilität zeigte im I. Rinversuch ein κ=0,58 und 0,59 im II. Ringversuch. Für 169Teilnehmer des I. und II. Ringversuchs war die Berechnung der Intraobserver-Reliabilität möglich und zeigte im Durchschnitt ein κ=0,62. Die Resultate der 3 deutschlandweiten Urinzytologieringtests zeigen eine hohe Sensitivität in der Detektion von klinisch relevanten High-grade-Urothelkarzinomen. Die erreichten κ-Werte repräsentieren eine gute Übereinstimmung der zytologischen Beurteilung. Urinary cytology is a non-invasive adjunct to cystoscopy in the diagnosis of bladder cancer. In order to assess the diagnostic accuracy of urinary cytology as an office-based method for clinically relevant high grade (G3) bladder cancer, three nationwide cytology survey tests were performed. Urine specimens from seven patients, three patients with high grade (G3) bladder cancer and four patients with urinary tract infections, were collected. A total of 1,000 cytology slides were produced from each urine specimen. Each set contained five slides (two malignant, three benign) which were sent to all participating German urologists. Three nationwide tests were performed from 1998-2000. The specimen sets were kept the same for the first and second test and in the third test two new slides were introduced. In addition to validity, the reliability was calculated for the first and second test as interobserver and intraobserver reliability according to Cohen’s kappa statistics. Due to the change of two specimens in the third test in 2000 only sensitivity and specificity were calculated. A total of 335 urologists took part in the first survey test, 329 in the second and 292 in the third The sensitivity for G3 cytologies was 81.34% in the first, 87.08% in the second and 85.1% in the third survey test and the specificity was 85.87%, 83.58% and 89.15%, respectively. Interobserver reliability showed a weighted kappa value of 0.58 for the first and 0.59 for the second survey test. Calculation of intraobserver reliability was possible for 169 urologists taking part in the first and second survey test and showed a mean kappa value of 0.62. The results of the three nationwide urinary cytology tests indicate that urinary cytology has a high sensitivity in the detection of clinically relevant high grade bladder cancer. The kappa values achieved demonstrate a clear agreement of cytological diagnoses.
    Der Urologe 09/2009; 48(9):1018-1024. DOI:10.1007/s00120-009-2077-2 · 0.44 Impact Factor
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    ABSTRACT: In der Prostatakarzinomfrüherkennung hat sich bei einer tPSA-Erhöhung im Bereich von 4–10ng/ml und negativem Palpationsbefund die zusätzliche Bestimmung des f/t-PSA-Quotienten als effektives Werkzeug in der Entscheidungsfindung pro oder contra Prostatabiopsie etabliert. Um eine optimale Effektivität des f/t-PSA-Quotienten zu gewährleisten, sollte aufgrund der relativen Instabilität des fPSA ein schnellstmögliches Abseren und eine Probenanalyse erfolgen. Falls eine unmittelbare Analyse nicht möglich ist, sollte das abzentrifugierte Serum bis zur Analyse möglichst eingefroren oder bei maximal 4°C gelagert werden. Wie die präsentierten Daten zeigen, kommt es ansonsten bei Anwendung der literaturseits etablierten fPSA-Schwellenwerte zu einem deutlichen Spezifitätsverlust des f/t-PSA-Quotienten. Der eigentliche Vorteil des f/t-PSA-Quotienten, den Biopsieanteil zu reduzieren, wird dadurch deutlich verringert. Um diesem Qualitätsverlust bei verzögerter Probenprozessierung vorzubeugen, empfiehlt es sich, die eigenen Ergebnisse, z.B. aus der niedergelassenen Praxis kritisch mit den präsentierten Daten zu vergleichen und ggf. eine individuelle Anpassung der Grenzwerte für den f/t-PSA-Quotienten vorzunehmen. Especially in the setting of total prostate-specific antigen (PSA) in the intermediate range of 4–10ng/ml and a negative digital rectal examination, the use of the free/total (F/T) PSA ratio has proved to be an effective tool in prostate cancer screening. Whole blood should be analyzed as soon as possible after venipuncture to ensure optimal effectiveness of the F/T PSA ratio. If an immediate serum analysis is not possible, the serum should be frozen or stored at a maximum of 4°C for a short period. Otherwise, when applying the F/T PSA cutoffs as recommended in the literature to a cohort with delayed analysis, a lack of specificity arises, and the initial advantage of reducing biopsies is minimized. To prevent loss of quality in a setting with delayed F/T PSA measurement, we recommend that physicians compare their own data critically with presented results and eventually adapt the cutoffs individually.
    Der Urologe 09/2009; 48(9):1002-1007. DOI:10.1007/s00120-009-2075-4 · 0.44 Impact Factor
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    ABSTRACT: In the prostate specific antigen (PSA) range of 4-10 ng/ml after a negative digital rectal examination, the PSA value indicates a lack of specificity with a carcinoma detection rate of roughly 20%. To improve the biopsy/carcinoma ratio, the interdisciplinary consensus recommends free PSA (fPSA) measurement. This does not take into account the pre-analysis when the cutoff value is established for biopsy indication. In the present study, an in-patient cohort whose blood samples were immediately analysed was compared with an out-patient cohort whose sample processing was delayed by between 24 and 48 h. The in-patient cohort comprises 382 patients with 99 prostate carcinomas, the out-patient cohort 987 patients with 235 carcinomas. In the in-patient cohort a sensitivity of 90% with a cutoff value of 25% for the f/t-PSA ratios is achieved with the theoretical possibility of reducing the number of punch biopsies by 34.6%. A sensitivity of 90% in the out-patient cohort necessitates a cutoff value of 18% for the f/t-PSA ratios. The specificity is 35.3% with a possible biopsy reduction of 29.1%. The cutoff values from cohorts with an immediate fPSA measurement cannot be adopted for a typical out-patient cohort whose analyses are delayed. On the contrary, an individual adjustment is necessary which corresponds to the pre-analysis.
    World Journal of Urology 07/2009; 27(5):581-5. DOI:10.1007/s00345-009-0441-x · 3.42 Impact Factor
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    ABSTRACT: While international screening studies for prostate cancer are by now almost reaching the estimated number of recruitments mandatory for the necessary power to investigate an effect on mortality of prostate cancer, no statistical figures on the detection of prostate cancer in Germany - apart from historical data before the use of prostate-specific antigen (PSA) are available. In order to generate a database and to investigate the diagnostic efficacy of the primarily practice-based urological care system, a case finding study designed as a nationwide longitudinal early detection trial was initiated. In one week in November 1997, 963 urologists prospectively examined 11,644 men between 45 and 75 years of age by digital rectal examination (DRE) and PSA with 4.0 ng/ml as cutoff. Data of family history and physical examination were collected by questionnaire. At this time participants were not aware of their PSA value. PSA was determined in the study center. Indication for sextant biopsy was a PSA value above 4.0 ng/ml or a suspicious lesion on DRE. Any indicated biopsy not performed had to be clarified. In a second questionnaire results of prostate biopsy, treatment and tumor status were documented. The mean age of the study population was 62 years (median 62). The PSA median was 1.4 ng/ml with 82.8% presenting with < 4.0 ng/ml, 12.8% with 4-10 ng/ml and 4.4% with >10 ng/ml. From 1,115 men (47.7%) biopsied, 262 cancers were detected resulting in a detection rate of 23.5%. While 399 men refused biopsy, further investigation was not recommended in 387 men by their urologist, because prostatitis or benign hyperplasia was thought to be the cause for elevated PSA. From the 143 patients undergoing radical prostatectomy, 93 (65%) cancers were organ confined. T(1c) cancers with elevated PSA > 10 ng/ml could be treated with curative intent in 44% only. The positive predictive value (PPV) was estimated to be 16% for DRE alone (14/90), 17% for PSA alone (143/819) and 51% for the combination of both (105/206). In that cohort, use of age-adjusted PSA values and PSA density increased the PPV of PSA testing nonsignificantly. Significant higher PPV indicated that utilizing a combination of both DRE and PSA is most effective in the early detection of prostate cancer. Unnecessary biopsies can be avoided using either age-adjusted PSA value or PSA density, but the PPV is not significantly changed and potentially curable cancer is missed in up to 25%. Given the substantial variability of the diagnostic approach despite the study design, uniform guidelines are necessary to ensure countrywide sufficient screening.
    European Urology 03/2001; 39(2):131-7. DOI:10.1159/000052427 · 12.48 Impact Factor
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    ABSTRACT: Measurement of serum prostate-specific antigen (PSA) is widely used as an aid in early detection of prostate cancer. Most patients with prostate cancer and a PSA level less than 10.0 ng/ml have early-stage disease. Thus, the detection of prostate cancer in its potentially curable stages requires the use of low PSA cutoffs, inevitably leading to many unnecessary biopsies. The combined use of free PSA and total PSA increases specificity of early detection. To develop risk assessment guidelines and a cutoff value of ratio of free (f) to total (t) PSA with a high predictive value for prostate cancer in men to whom the test would be applied in real life practice, a multicenter early detection trial was initiated. In one week in November 1997, 963 urologists prospectively examined 11,644 men between 45 and 75 years by digital rectal examination (DRE) and prostate-specific antigen with 4.0 ng/ml as cutoff. Data of physical examination were collected by questionnaire. At this time participants were not aware of their PSA values. Suspicious findings were further investigated with sextant biopsy. Prostate volume was determined with transrectal ultrasound (TRUS). Different cutoff levels were correlated to age and detection rate. From1,115 biopsied men, the data of 633 men fulfilled the criteria DRE-negative, TRUS-estimated volume, and PSA 4.0-10.0 ng/ml. In that cohort 91 cancers were detected. Percentage of fPSA was significantly more predictive of cancer than tPSA (p < 0.001). The area under the ROC curve was 0.72 for percent fPSA (% fPSA) and 0.62 for total PSA. The cancer risk nearly doubled using a cutoff of 10% fPSA, the median %PSA level of the detected cancers. A better discrimination of cancer and noncancer especially in the age group above 70 years is possible. Using a cutoff of 16% fPSA increases positive predictive value (PPV) to 25% missing only 4% of cancers. Nearly 45% of the biopsies could be avoided. In the age group 45-69 years, a cutoff of 20% fPSA leads to PPV of 15%, missing 6% of cancers. Unnecessary biopsies could be avoided in 12%. Using % fPSA in early detection of prostate cancer reduces the number of unnecessary biopsies, especially in men with negative rectal examination in the PSA range of 4.0-10.0 ng/ml. In order to diminish biopsy rate in men 70 years or older a cutoff of 16% fPSA should be used. A cutoff of 20% fPSA in men younger than 70 years is recommended to increase sensitivity in that age group.
    Onkologie 03/2001; 24(1):33-7. DOI:10.1159/000050279 · 0.84 Impact Factor

Publication Stats

56 Citations
23.68 Total Impact Points

Institutions

  • 2001–2011
    • University Hospital Essen
      • Klinik für Urologie
      Essen, North Rhine-Westphalia, Germany
    • Martin Luther University Halle-Wittenberg
      Halle-on-the-Saale, Saxony-Anhalt, Germany