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Volker Schneider

Publications and source records attributed to Volker Schneider.

7 recordsLinked to original sources
PubMed2004

[Molecular diagnosis of cervical neoplasia: future potential or academic playground?].

Despite major progress in the reduction of incidence and mortality of cervical carcinoma through systematic screening by cytology, there are areas which deserve further improvement, one of them being the obvious overtreatment of CIN 3 which has to be removed in all patients although the invasive potential is limited to a minority of those lesions. Based on new knowledge of cervical carcinogenesis uncovered in the last few years, new potential targets for an individualized determination of prognostic behaviour may become possible. Infection by high-risk HPV types has been recognized as an essential step in the development of cervical carcinoma. In virally induced cervical carcinogenesis, dysregulation of the cell cycle is induced by an overexpression of the oncogenes E6 and E7. Direct determination of these oncogenes may become possible by mRNA measurements. Other biomarkers of cell cycle dysregulation such as p16 may serve in the future to determine the invasive potential of the precursors of cervical carcinoma. Further discoveries in molecular carcinogenesis may possibly allow to develop new diagnostic markers and possibly therapeutic agents in the future.

Cervix Uteri↗
PubMed2003

Symposium part 2: Should the Bethesda System terminology be used in diagnostic surgical pathology?: Counterpoint.

The criteria currently used for grading cervical intraepithelial neoplasia (CIN) are arbitrary and subjective with consequent considerable intra- and interobserver variability. None of the currently used criteria make a clear-cut case for changing terminology. The combination of CIN 2 and CIN 3 into a high-grade lesion is not supported by biologic behavior or HPV typing and leads to overtreatment. The various shifts in nomenclature over the last 50 years through the dysplasia, CIN, and Bethesda systems, although intellectually stimulating, have neither improved diagnostic accuracy nor patient management. On the contrary, they often caused confusion and duplication, leading to the common and ironic practice that several terminologies are now being used in an additive fashion. New diagnostic markers are on the horizon as a result of the rapid development in the areas of genomics and proteomics. It seems likely that specific molecular biomarkers will become available, allowing the consistent and accurate discrimination between those intraepithelial lesions that will ultimately become invasive from the vast majority of lesions that will regress or persist. It is preferable at this time to maintain the current three-tier system, which is well entrenched and accepted around the world, until a novel approach places the classification of cervical precursor lesions on a new and solid footing. Ideally, we will then have a single-tier system identifying reliably those lesions that have the potential to become invasive.

Female↗
PubMedDate not supplied

Morphologic characteristics of p16INK4a-positive cells in cervical cytology samples.

OBJECTIVE: Overexpression of p16INK4a has been proposed as a biomarker helpful for the identification of dysplastic cervical epithelial cells on histologic slides as well as in cervical smears. Since a few nontransformed cells in the genital tract in some instances may also express p16INK4a, we evaluated whether applying established morphologic criteria for cervical dysplasia allows a distinction of dysplastic from nondysplastic p16INK4a-stained cells in cytologic samples. STUDY DESIGN: Liquid-based cytology samples were obtained from a screening population (n=50), and from patients attending a dysplasia clinic (n=40). Slides prepared from these samples were stained with the conventional Papanicolaou stain procedure. From each specimen, a second slide was prepared in parallel and immunostained for p16INK4a. Cytologic diagnoses for most patients attending the dysplasia clinic could be compared to the reported histologic diagnoses on punch biopsy samples taken from the patients at the time of colposcopy. This allowed a comparison of the cytology and p16INK4a immunostaining results with subsequent hematoxylin and eosin-based histologic diagnoses. RESULTS: Overall, in 10% of slides obtained from patients with nonsuspicious smears, few p16INK4a-positive cells were found. Using established morphologic criteria and applying these criteria on cells showing any p16INK4a immunoreactivity, p16INK4a-positive normal or metaplastic cells could be discriminated from p16INK4a-expressing dysplastic cells. In 21 of 22 cases (95%) of high grade lesions (cervical intraepithelial neoplasia 2 or higher in follow-up histology), easily recognizable p16INK4a-positive dysplastic cells could be detected, with the remaining case lacking dysplastic cells in the thin-layer slide used for p16INK4a immunostaining. CONCLUSION: Established morphologic criteria for cervical dysplasia can be readily applied to p16INK4a-immunostained cytologic specimens. Thus, p16INK4a immunostaining may help to avoid ambiguities in the interpretation of cervical cytology samples and facilitate more rapid diagnosis and possibly even automated screening of cytologic slides.

Aged↗