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Featured researches published by Karin Hofmann.


Clinical Chemistry and Laboratory Medicine | 2011

The diagnostic accuracy of two human epididymis protein 4 (HE4) testing systems in combination with CA125 in the differential diagnosis of ovarian masses.

Miriam Lenhard; Petra Stieber; Linda Hertlein; Angela Kirschenhofer; Sophie Fürst; Doris Mayr; Dorothea Nagel; Karin Hofmann; Katja Krocker; Alexander Burges

Abstract Background: Cancer antigen 125 (CA125) is the best known single tumor marker for ovarian cancer (OC). We investigated whether the additional information of the human epididymis protein 4 (HE4) improves diagnostic accuracy. Methods: We retrospectively analyzed preoperative sera of 109 healthy women, 285 patients with benign ovarian masses (cystadenoma: n=78, leimyoma: n=66, endometriosis: n=52, functional ovarian cysts: n=79, other: n=10), 16 low malignant potential (LMP) ovarian tumors and 125 OC (stage I: 22, II: 15, III: 78, IV: 10). CA125 was analyzed using the ARCHITECT system, HE4 using the ARCHITECT(a) system and EIA(e) technology additionally. Results: The lowest concentrations of CA125 and HE4 were observed in healthy individuals, followed by patients with benign adnexal masses and patients with LMP tumors and OC. The area under the curve (AUC) for the differential diagnosis of adnexal masses of CA125 alone was not significantly different to HE4 alone in premenopausal (CA125: 86.7, HE4(a): 82.6, HE4(e): 81.6% p>0.05) but significantly different in postmenopausal [CA125: 93.4 vs. HE4(a): 88.3 p=0.023 and vs. HE4(e): 87.8% p=0.012] patients. For stage I OC, HE4 as a single marker was superior to CA125, which was the best single marker in stage II-IV. The combination of CA125 and HE4 using risk of malignancy algorithm (ROMA) gained the highest sensitivity at 95% specificity for the differential diagnosis of adnexal masses [CA125: 70.9, HE4(a): 67.4, HE4(e): 66.0, ROMA(a): 76.6 and ROMA(e): 74.5%], especially in stage I OC [CA125: 27.3, HE4(a): 40.9, HE4(e): 40.9, ROMA(a): 45.5 and ROMA(e): 45.5%]. Conclusions: CA125 is still the best single marker in the diagnosis of OC. HE4 alone and even more the combined analysis of CA125 and HE4 using ROMA improve the diagnostic accuracy of adnexal masses, especially in early OC.


Clinical Chemistry and Laboratory Medicine | 1993

Comparison of Cytokeratin Fragment 19 (CYFRA 21-1), Tissue Polypeptide Antigen (TPA) and Tissue Polypeptide Specific Antigen (TPS) as Tumour Markers in Lung Cancer

Petra Stieber; H. Dienemann; Ute Hasholzner; Christian Müller; Susanne Poley; Karin Hofmann; A. Fateh-Moghadam

Recently CYFRA 21-1, a new tumour marker measuring a fragment of cytokeratin 19, was introduced and proved to be suitable for the follow-up care and monitoring of the therapy of non-small cell lung carcinomas, especially squamous cell carcinomas of the lung. Besides CYFRA 21-1, there are two other tumour markers available, called tissue polypeptide antigen (TPA) and tissue polypeptide specific antigen (TPS), which also measure different cytokeratins in serum. In a retrospective study we investigated the clinical significance of these 3 cytokeratin markers in lung cancer compared with carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC) and neuron-specific enolase (NSE). We investigated the sera of 50 healthy persons, 273 patients with various benign diseases and 218 patients with histologically proven lung cancer. In a first step the specificity versus benign diseases of the lung was established for all the markers, and was fixed at 95%. Then the single and combined sensitivities were calculated. CYFRA 21-1 proved to possess the highest sensitivity in lung cancer in general (61%), in non-small cell lung carcinomas (64%), in squamous cell carcinomas (79%), in adenocarcinomas (54%) and in large cell carcinomas (65%). In small cell lung carcinomas, neuron-specific enolase proved again to be the marker of first choice (55%). Combined determinations proved clearly increased sensitivity only for large cell carcinomas (CYFRA 21-1 + TPA: 77%) and for small cell lung carcinomas (CYFRA 21-1 + NSE: 62%).(ABSTRACT TRUNCATED AT 250 WORDS)


Clinical Chemistry and Laboratory Medicine | 2012

Human epididymis protein 4 (HE4) in benign and malignant diseases

Linda Hertlein; Petra Stieber; Angela Kirschenhofer; Sophie Fürst; Doris Mayr; Karin Hofmann; Katja Krocker; Dorothea Nagel; Miriam Lenhard; Alexander Burges

Abstract Background: Human epididymis protein 4 (HE4) is described as a useful new biomarker in ovarian cancer. As HE4 is neither tumor nor organ specific, we intensively investigated the occurrence of this protein in female and male patients with various benign and malignant diseases in order to avoid misinterpretation and to identify potential additional clinical relevance. Methods: We retrospectively investigated HE4 (ARCHITECT®, Abbott Diagnostics, US) in the sera of 205 healthy individuals, 654 patients with benign disorders and 720 patients with cancer before initial treatment. Results: The lowest concentrations of HE4 were observed in healthy men (median 26.2 pmol/L) followed by healthy women (median 40.4 pmol/L). In benign diseases, highest HE4 concentrations were seen in both women and men with renal failure (women, median 1041 pmol/L; men, median 1368 pmol/L). In women, the highest HE4 levels in malignant diseases were observed in ovarian cancer (median 242 pmol/l), whereas the highest HE4 concentrations in men occurred in lung cancer (median 89.2 pmol/L). The area under the curve (AUC) of HE4 in women was highest in ovarian cancer and borderline tumors as compared to benign gynecological disorders (88.9%), with a sensitivity of 67.4% at 95% specificity. Also, significantly elevated concentrations of HE4 with reference to the respective group of benign diseases were observed in uterus corpus and breast cancer as well as in lung cancer for men and women. Conclusions: HE4 has the highest relevance in ovarian cancer but can be elevated in a variety of benign and malignant diseases.


International Journal of Biological Markers | 1994

Comparison of CYFRA 21-1, TPA and TPS in lung cancer, urinary bladder cancer and benign diseases.

Petra Stieber; H. Dienemann; Ute Hasholzner; P. G. Fabricius; C. Schambeck; M. Weinzierl; S. Poley; W. Samtleben; Karin Hofmann; W. Meier; Untch M; A. Fateh-Moghadam

Recently CYFRA 21–1, a new tumor marker measuring a fragment of cytokeratin 19, was introduced and proved to be suitable for therapy monitoring and follow-up of non-small cell lung carcinomas (NSCLC), in particular squamous cell carcinomas. Besides CYFRA 21–1 there are two other tumor markers, tissue polypeptide antigen (TPA) and tissue polypeptide-specific antigen (TPS), which also measure various cytokeratins in serum. In a retrospective study we investigated the clinical significance of these three cytokeratin markers in lung cancer and in carcinoma of the urinary bladder. For this purpose we investigated the sera of 50 healthy persons, 273 patients with various benign diseases, 218 patients with histologically proven lung cancer and 88 patients with carcinoma of the urinary bladder. In a first step the specificity was established for the different reference groups and the cutoff values were fixed at a specificity of 95%. In lung cancer the single and combined sensitivities were calculated versus benign lung diseases (n = 58) as reference group. With single determinations CYFRA 21–1 proved to have the highest sensitivity in lung cancer in general (61%), in non-small cell lung carcinomas (64%), in squamous cell carcinomas (79%), in adenocarcinomas (54%) and in large cell carcinomas (65%). In small cell lung carcinomas (SCLC) NSE was confirmed to be the marker of choice (55%). With combined determinations a clear increase in sensitivity could only be reached in large cell carcinomas (CYFRA 21–1 + TPA: 77%) and in small cell carcinomas (CYFRA 21–1 + NSE: 62%). In cancer of the urinary bladder the sensitivities were established versus benign urological diseases (n = 73). CYFRA 21–1 showed with 38% true positive test results the highest sensitivity compared to TPA (27%) and TPS (23%). From our investigations it was evident that TPA detects at least partially the same substance as CYFRA 21–1 (the sensitivities compared to the markers TPS, CEA, SCC and NSE were rather high, but not as high as for CYFRA 21–1) whereas TPS represents a completely different parameter of clinical chemistry (lowest number of true positive test results over the whole investigation), which apparently measures something completely different. These findings cleary correspond with the very recent results of immunoblotting comparing CYFRA 21–1, TPA and TPS.


Clinical Chemistry and Laboratory Medicine | 2003

Measurements of Complement Factor H-Related Protein (BTA-TRAK™ Assay) and Nuclear Matrix Protein (NMP22 Assay) - Useful Diagnostic Tools in the Diagnosis of Urinary Bladder Cancer?

Brigitte Mahnert; Stephan Tauber; Martin Kriegmair; Dorothea Nagel; Stefan Holdenrieder; Karin Hofmann; W. Reiter; N. Schmeller; Petra Stieber

Abstract Between 1997 and 2000 we investigated in a prospective study the voided urine samples of all consecutive patients undergoing cystoscopy independent from their clinical background (n = 705) with the BTA-TRAK™ assay (Bard Diagnostics, Redmont, USA) detecting a complement factor H-related protein (CFHrP) and the NMP22 assay (Matritech, Newton, USA) measuring a nuclear matrix protein, which is supposed to be specific for bladder cancer. The individuals were divided into three groups concerning the clinical background: 233 patients had urological diseases, 268 patients had urinary bladder cancer and 150 patients had other urological malignancies. Based on the clinical findings we compared our results with well established diagnostic methods for urinary bladder cancer such as cytology and the detection of hematuria. In addition, we investigated urine samples from 30 healthy individuals and 24 patients with urinary tract infection without performing cystoscopy. Following the recommendations of the European Group on Tumor Markers we used 95% specificity for benign urological diseases and urinary tract infections, which resulted in a sensitivity of 17% for active bladder cancer for the BTA-TRAK™ assay and 31% for NMP22. We compared these results with the detection of hematuria (specificity: 72%) and cytology, which had a sensitivity of 64% and 89%, respectively. Subsequently, we calculated sensitivity and specificity for the detection of relapse of the disease. Again using 95% specificity, in this case for patients with no evidence of disease (NED), in patients with recurrent disease the BTA-TRAK™ assay showed 8% sensitivity as compared to 12% for the NMP22 assay. Due to an insufficient specificity and sensitivity, both tests can neither be clinically useful in screening of high risk patients, nor in primary diagnosis of bladder cancer. They cannot replace neither cystoscopy nor cytology. In the follow-up care more investigations may be necessary to prove the benefit of existing diagnostic strategies for the discrimination between active and inactive bladder cancer.


Clinical Chemistry and Laboratory Medicine | 2009

Development and analytical performance evaluation of an automated chemiluminescent immunoassay for pro-gastrin releasing peptide (ProGRP)

Toru Yoshimura; Kenju Fujita; Hideki Kinukawa; Yoshiharu Matsuoka; Rahul D. Patil; Gangamani S. Beligere; Sabrina S. Chan; Barry L. Dowell; Lori J. Sokoll; Debra J. Elliott; Daniel W. Chan; Cornelia Scheuer; Karin Hofmann; Petra Stieber; Yousuke Sakurai; Masayuki Iizuka; Haruhisa Saegusa; Ken Yamaguchi

Abstract Background: Pro-gastrin releasing peptide (ProGRP) concentrations in blood play an important role in the diagnosis and treatment of patients with small cell lung cancer (SCLC). The automated quantitative ARCHITECT® ProGRP assay was developed to aid in the differential diagnosis and in the management of SCLC. The purpose of this study was to evaluate the analytical performance of this chemiluminescent microparticle immunoassay at multiple sites. Methods: ARCHITECT ProGRP measures ProGRP using a two-step sandwich using monoclonal anti-ProGRP antibodies coated on paramagnetic microparticles and labeled with acridinium. Analytical performance of the assay was evaluated at four sites: Abbott Japan, Denka Seiken, the Johns Hopkins University, and the University of Munich. Results: Total precision (%CV) for nine analyte concentrations was between 2.2 and 5.7. The analytical sensitivity of the assay was between 0.20 pg/mL and 0.88 pg/mL. The functional sensitivity at 20% CV was between 0.66 pg/mL and 1.73 pg/mL. The assay was linear up to 50,000 pg/mL using a 1:10 autodilution protocol. The calibration curve was stable for 30 days. Comparison with the Fujirebio microtiter plate enzyme-linked immunosorbent assay (EIA) ProGRP assay gave a slope of 0.93 and a correlation coefficient (r) of 0.99. Conclusions: These results demonstrate that the ARCHITECT ProGRP assay has excellent sensitivity, precision, and correlation to a reference method. This assay provides a convenient automated method for ProGRP measurement in serum and plasma in hospitals and clinical laboratories. Clin Chem Lab Med 2009;47:1557–63.


Labmedicine | 2015

Improved diagnosis of mesothelioma by a combination of soluble mesothelin-related peptide and CYFRA 21-1

Stefan Holdenrieder; Rudolf Hatz; Karin Hofmann; Andreas Schalhorn; Petra Stieber

Abstract Background: Soluble mesothelin-related peptide (sMRP) has shown great potential for malignant mesothelioma detection. However, data on comparison with other cancer and benign diseases as well as with other established lung cancer biomarkers are rare. Methods: In this study, SMRP was investigated in sera from 1506 individuals including 147 healthy donors, 285 patients with diverse benign diseases and 1074 patients with mesothelioma (n=39) and various malignant tumors (lung, gastrointestinal, gynecological, urological). For differential diagnosis of lung diseases, carcinoembryonic antigen, cytokeratin 19-fragments (CYFRA 21-1), neuron-specific enolase and squamous cell cancer antigen were determined additionally. Results: Ninety-fifth percentiles of sMRP serum levels in healthy persons were 1.2 nM, in patients with benign diseases between 2.0 and 3.8 nM and in cancer patients between 1.5 and 44.3 nM. Highest values were observed in mesothelioma (median 2.3 nM; 95th percentile 44.3 nM). When differential diagnostic capacity of cancer detection vs. the relevant benign control group was tested, sMRP showed best results for mesothelioma and ovarian cancer with a sensitivity of 45% and 37%, respectively, at 95% specificity. At 100% specificity vs. normal controls, sensitivity for mesothelioma detection was found to be 59% for sMRP, 73% for CYFRA 21-1 and 88% for the combination of both. At 95% specificity vs. all other lung diseases, sensitivity for mesothelioma was 48% for sMRP, 15% for CYFRA 21-1 and 46% for the combination of both. Conclusions: In summary, SMRP is a valuable serum biomarker that is specific at high concentrations for the detection of malignant mesothelioma. For screening purposes, the combination with CYFRA 21-1 improves the sensitivity at high specificity.


Labmedicine | 2013

Pattern of S100-release in benign and malignant diseases beside malignant melanoma/Freisetzung von S100 bei benignen und malignen Erkrankungen jenseits des malignen Melanoms

Stefan Holdenrieder; Fritz Spelsberg; Rudolf Hatz; Raphaela Waidelich; Michael Untch; Karin Hofmann; Birgit Wehnl; Volker Heinemann; Petra Stieber

Abstract Background: The usefulness of S100 as a prognostic marker and aid in follow-up care in patients with malignant melanoma as well as in individuals with various neurological pathologies is well known. The aim of this study was to investigate its release and clinical relevance in benign and malignant disorders beyond these indications to elucidate tumor and organ specificity of S100. Methods: S100 levels were studied in serum samples of 1856 untreated patients, among them 59 healthy individuals, 358 patients with benign disorders, and 1439 patients with malignant tumors. Results: Healthy individuals had low S100 levels reaching a median of 0.041 ng/mL and 95th and 100th percentiles of 0.096 ng/mL and 0.144 ng/mL, respectively. The medians of patient groups with benign diseases ranged from 0.030 to 0.057 ng/mL, patients with malignant diseases from 0.020 to 0.059 ng/mL, and thus were comparable to healthy individuals. Only 2% of patients with benign diseases, mainly suffering from infectious, autoimmune, or benign gastrointestinal diseases and 1% of patients with malignant diseases showed slightly higher values than healthy individuals, in most cases up to 0.5 ng/mL. Conclusions: In contrast to many other oncological biomarkers, S100 is only rarely released in elevated levels from most benign and malignant diseases apart from malignant melanoma and neurological diseases, resulting in superior organ and tumor specificity. As potentially influencing factors, severe infectious diseases have to be considered. Zusammenfassung Hintergrund: S100 ist als nützlicher Biomarker für die Prognoseaschätzung und die Verlaufsbeobachtung bei Patienten mit malignem Melanom und in Patienten mit verschiedenen neurologischen Erkrankungen anerkannt. Das Ziel dieser Studie war, die Freisetzung und klinische Relevanz von S100 bei anderen benignen and malignen Erkrankungen jenseits dieser Indikationen zu untersuchen, um die Tumor- und Organspezifität von S100 zu bewerten. Methoden: S100-Konzentrationen wurden in Serumproben von 1856 unbehandelten Patienten ermittelt, darunter 59 gesunde Personen, 358 Patienten mit benignen Erkrankungen und 1439 Patienten mit malignen Tumoren. Ergebnisse: Gesunde Personen hatten niedrige S100 Serumwerte, die einen Median von 0.041 ng/mL, eine 95. Perzentile von 0.096 ng/mL und ein Maximum von 0.144 ng/mL erreichten. Die Mediane der Patientengruppen lagen bei benignen Erkrankungen zwischen 0.030 und 0.057 ng/mL, bei Patienten mit malignen Tumoren zwischen 0.020 und 0.059 ng/mL – und waren somit vergleichbar zu gesunden Kontrollpersonen. Lediglich 2% der Patienten mit benignen Erkrankungen, v.a. infektiösen, autoimmunen oder benignen gastrointestinalen Erkrankungen, sowie 1% der Patienten mit malignen Tumoren wiesen im Vergleich zu gesunden Personen leicht erhöhte Werte auf – in den meisten Fällen bis 0.5 ng/mL. Schlussfolgerung: Im Gegensatz zu vielen anderen onkologischen Biomarkern wird S100 nur selten in höheren Konzentrationen von den meisten benignen und malignen Erkrankungen – mit Ausnahme des malignen Melanoms und neurologischer Erkrankungen – freigesetzt, was sich in einer sehr hohen Organ- und Tumorspezifität widerspiegelt. Als möglicher Einflussfaktor sind schwere infektiöse Erkrankungen zu berücksichtigen.


Laboratoriumsmedizin-journal of Laboratory Medicine | 1997

Pro-Gastrin-Releasing Peptide (ProGRP) - ein neuer Tumormarker beim kleinzelligen Bronchialkarzinom. Pro-Gastrin-Releasing Peptide (ProGRP) - A New Marker in Small-Cell Lung Carcinomas

Petra Stieber; Hendrik Dienemann; Ursula Schmitt; Ute Hasholzner; W. Reiter; Karin Hofmann; Andreas Schalhorn; K. Yamaguchi

Zusammenfassung: In den letzten Jahren ist wiederholt auf das gehäufte Vorkommen des Gastrin-Releasing-Peptides (GRP) beim kleinzelligen Bronchialkarzinom hingewiesen worden. Bei GRP handelt es sich um ein Hormon des Magens, welches das Korrelat der Säugetiere zum Bombesin der Amphibien darstellt. Yamaguchi et al. entwickelten auf der Basis von rekombinantem ProGRP einen Sandwich ELISA zum Nachweis des stabileren Vorläufers von GRP im Serum. Anhand von 604 Serumproben von Patienten mit verschiedensten benignen Erkrankungen sowie malignen Tumoren der Lunge untersuchten wir den Stellenwert von ProGRP beim kleinzelligen und nicht kleinzelligen Bronchialkarzinom im Vergleich zu bereits gut etablierten tumorassoziierten Antigenen wie der neuronspezifischen Enolase (NSE), CYFRA 21-1 (Cytokeratin 19-Fragmente) und dem karzinoembryonalen Antigen (CEA). Bei 95%iger Spezifität gegenüber benignen Lungenerkrankungen zeigte sich eine nahezu vergleichbare Empfindlichkeit von ProGRP und NSE (47% gegenüber 45%) für das kleinzellige Bronchialkarzinom, wobei sich ProGRP durch besonders hohe Wertlagen auszeichnete. Sowohl ProGRP als auch NSE waren isoliert in ähnlich vielen Fällen richtig positiv, die gemeinsame Bestimmung führt zu einer Steigerung der Empfindlichkeit *auf 62%. Beim nicht kleinzelligen Bronchialkarzinom erwies sich CYFRA 21-1 mit 63% richtig positiven Ergebnissen erneut als mit Abstand führender Marker. Insbesondere ProGRP, aber auch NSE, zeigten hier nur wenige positive Testergebnisse im niedrigen Wertebereich, so daß bei unklaren Lungenrundherden die Bestimung dieser Tumormarker differentialdiagnostisch unterstützend sein kann.


Tumor Biology 18(SUPPL | 1997

Is PSA-ACT superior to total PSA in prostate cancer?

Petra Stieber; N. Schmeller; W. Reiter; Ursula Schmitt; Karin Hofmann

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Daniel W. Chan

Johns Hopkins University

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Lori J. Sokoll

Johns Hopkins University

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