Wolfgang Kuehn - Academia.edu (original) (raw)

Papers by Wolfgang Kuehn

Research paper thumbnail of DNA-Zytometrie am Abstrich der klinisch und zytologisch auffälligen Portio

Geburtshilfe und Frauenheilkunde, 1998

Research paper thumbnail of Errata: Evaluation of Raman spectroscopic macro raster scans of native cervical cone biopsies using histopathological mapping

Journal of Biomedical Optics, 2014

Research paper thumbnail of The prognostic significance of determining DNA content in breast cancer by DNA image cytometry: the role of high grade aneuploidy in node negative breast cancer

Journal of Clinical Pathology, 2007

To investigate the role of DNA aneuploidy, particularly in patients with node negative breast can... more To investigate the role of DNA aneuploidy, particularly in patients with node negative breast cancer, in order to identify the different risk profiles within the pool of heterogeneous breast cancers. Methods: Imprint smears from 370 breast carcinomas were Feulgen-stained and measured by DNA image analysis. DNA aneuploidy was graded by the amount of aneuploid cells (DNA content .5c) and highly aneuploid cells (DNA content .9c) in a breast tumour population. These results were correlated to the clinical long-term follow-up. A statistical cutoff value of .10 aneuploid cells (.5c) and of .1 highly aneuploid cell (.9c) was evaluated as significant for disease-free survival (DFS) and overall survival (OS). Results: Subgroups among patients with breast cancer with aneuploid cells below the cutoff value showed a significantly longer DFS and OS than those with aneuploid cells above this value. Patients with node negative breast cancer with .10 aneuploid cells (.5c) and .1 highly aneuploid cell (.9c) showed an unfavourable prognosis similar to patients with node positive breast cancer with ,10 aneuploid cells (.5c) and ,1 highly aneuploid tumour cell (.9c) in DFS and OS. Conclusion: Nuclear DNA content, as an objective marker of tumour aggressiveness, provides prognostic information in patients with both node negative and node positive breast cancer. Based on DNA aneuploidy, the clinically inhomogeneous group of patients with node negative breast cancer can be stratified into low-risk and high-risk subgroups. Therefore, DNA ploidy analysis may identify high-risk patients with lymph node negative breast cancer who might benefit from additional adjuvant therapy.

Research paper thumbnail of New Research on Colposcopy: Results of a Two-phase Study to Test Digital Colposcopy and Telecolposcopy in Clinical Practice

Journal of the Turkish German Gynecology Association Artemis

Objective: It is proposed that digital colposcopy and telecolposcopy should facilitate the medica... more Objective: It is proposed that digital colposcopy and telecolposcopy should facilitate the medical decision-making process and raise the validity of the diagnosis of cervical carcinoma thereby lowering the incidence and mortality rate of the disease. In order to test this, a digital colposcopy system was developed and clinically evaluated within the framework of a twophase scientific study at the Charité Dysplasia Clinic Berlin. Materials and Methods: In Phase 1 of the evaluation, a total of 315 patients were examined with the digital colposcopy system consisting of a binocular colposcope supplemented with a colour camera and PC, to see whether colposcopic findings can be re-evaluated on the basis of the stored digital images alone, i.e. without the patient being present. Phase 2 was used to test the technical feasibility and reliability of sending colposcopic images by electronic mail. A total of 30 patients from four selected gynecological practices in Berlin had been referred for diagnostic clarification to the Charité Dysplasia Clinic. The digital colposcopic images made there were sent as e-mails to the referring doctors, who in turn evaluated the data transfer. Results: In Phase 1, the primary and secondary examiners were in total agreement in 69% of the cases (κ=0.60). No significant bias in terms of under-or overrating was observed (p<0.05 by McNemar's test). In Phase 2, in 57% (n=17) of the cases, a lack of experience with the new technique led to difficulties with downloading the images. When the practices had become more familiar with the procedure, the incidence of problems fell from 90% (9/10), in the first half of the project, to 40% (8/20) in the second half. In 87% of the cases, the diagnosis of the consulting specialist at the Charité Dysplasia Clinic was comprehensible to the practising physicians. Discussion: Digital colposcopy and telecolposcopy can be effectively used in colposcopy to compensate for the inherent disadvantages of the method, i.e. a high level of inter-and intra-observer variability, inadequate reproducibility and objectivity of colposcopic findings, data storage, data transmission. In practice, there are clear advantages for the diagnosis documentation, follow-up monitoring, further medical education, as well as interdisciplinary communication.

Research paper thumbnail of Long Term Follow Up of Borderline Ovarian Tumors in Oncologic Center in Warsaw

International Journal of Gynecologic Cancer, 2003

Research paper thumbnail of DNA-Zytometrie am Abstrich der klinisch und zytologisch auffälligen Portio

Geburtshilfe und Frauenheilkunde, 1998

Research paper thumbnail of Errata: Evaluation of Raman spectroscopic macro raster scans of native cervical cone biopsies using histopathological mapping

Journal of Biomedical Optics, 2014

Research paper thumbnail of The prognostic significance of determining DNA content in breast cancer by DNA image cytometry: the role of high grade aneuploidy in node negative breast cancer

Journal of Clinical Pathology, 2007

To investigate the role of DNA aneuploidy, particularly in patients with node negative breast can... more To investigate the role of DNA aneuploidy, particularly in patients with node negative breast cancer, in order to identify the different risk profiles within the pool of heterogeneous breast cancers. Methods: Imprint smears from 370 breast carcinomas were Feulgen-stained and measured by DNA image analysis. DNA aneuploidy was graded by the amount of aneuploid cells (DNA content .5c) and highly aneuploid cells (DNA content .9c) in a breast tumour population. These results were correlated to the clinical long-term follow-up. A statistical cutoff value of .10 aneuploid cells (.5c) and of .1 highly aneuploid cell (.9c) was evaluated as significant for disease-free survival (DFS) and overall survival (OS). Results: Subgroups among patients with breast cancer with aneuploid cells below the cutoff value showed a significantly longer DFS and OS than those with aneuploid cells above this value. Patients with node negative breast cancer with .10 aneuploid cells (.5c) and .1 highly aneuploid cell (.9c) showed an unfavourable prognosis similar to patients with node positive breast cancer with ,10 aneuploid cells (.5c) and ,1 highly aneuploid tumour cell (.9c) in DFS and OS. Conclusion: Nuclear DNA content, as an objective marker of tumour aggressiveness, provides prognostic information in patients with both node negative and node positive breast cancer. Based on DNA aneuploidy, the clinically inhomogeneous group of patients with node negative breast cancer can be stratified into low-risk and high-risk subgroups. Therefore, DNA ploidy analysis may identify high-risk patients with lymph node negative breast cancer who might benefit from additional adjuvant therapy.

Research paper thumbnail of New Research on Colposcopy: Results of a Two-phase Study to Test Digital Colposcopy and Telecolposcopy in Clinical Practice

Journal of the Turkish German Gynecology Association Artemis

Objective: It is proposed that digital colposcopy and telecolposcopy should facilitate the medica... more Objective: It is proposed that digital colposcopy and telecolposcopy should facilitate the medical decision-making process and raise the validity of the diagnosis of cervical carcinoma thereby lowering the incidence and mortality rate of the disease. In order to test this, a digital colposcopy system was developed and clinically evaluated within the framework of a twophase scientific study at the Charité Dysplasia Clinic Berlin. Materials and Methods: In Phase 1 of the evaluation, a total of 315 patients were examined with the digital colposcopy system consisting of a binocular colposcope supplemented with a colour camera and PC, to see whether colposcopic findings can be re-evaluated on the basis of the stored digital images alone, i.e. without the patient being present. Phase 2 was used to test the technical feasibility and reliability of sending colposcopic images by electronic mail. A total of 30 patients from four selected gynecological practices in Berlin had been referred for diagnostic clarification to the Charité Dysplasia Clinic. The digital colposcopic images made there were sent as e-mails to the referring doctors, who in turn evaluated the data transfer. Results: In Phase 1, the primary and secondary examiners were in total agreement in 69% of the cases (κ=0.60). No significant bias in terms of under-or overrating was observed (p<0.05 by McNemar's test). In Phase 2, in 57% (n=17) of the cases, a lack of experience with the new technique led to difficulties with downloading the images. When the practices had become more familiar with the procedure, the incidence of problems fell from 90% (9/10), in the first half of the project, to 40% (8/20) in the second half. In 87% of the cases, the diagnosis of the consulting specialist at the Charité Dysplasia Clinic was comprehensible to the practising physicians. Discussion: Digital colposcopy and telecolposcopy can be effectively used in colposcopy to compensate for the inherent disadvantages of the method, i.e. a high level of inter-and intra-observer variability, inadequate reproducibility and objectivity of colposcopic findings, data storage, data transmission. In practice, there are clear advantages for the diagnosis documentation, follow-up monitoring, further medical education, as well as interdisciplinary communication.

Research paper thumbnail of Long Term Follow Up of Borderline Ovarian Tumors in Oncologic Center in Warsaw

International Journal of Gynecologic Cancer, 2003