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U Schenck

Publications and source records attributed to U Schenck.

At least 37 records · Page 2Linked to original sources
PubMed1989

Difficulties in evaluating urinary specimens after local mitomycin therapy of bladder cancer.

In order to describe the cytological changes induced by mitomycin in urinary specimens, we re-examined cytological specimens from patients with recurring bladder cancer treated by long-term intravesical mitomycin therapy after transurethral resection. Local mitomycin therapy causes an increase of leukocytes and urothelial cells, especially of the umbrella-cell type, in urinary specimens. During and after the application of mitomycin, the nucleus and the cytoplasm of urothelial cells are enlarged, usually proportionally. Urothelial cells frequently show a giant nucleus, multiple prominent nucleoli, and an enlarged foamy cytoplasm of the umbrella-cell type. Anisokaryosis is also seen. Such cytological changes are more remarkable later in the course of therapy and after the end of therapy, and they often confuse cytological interpretation. However, the nuclei of urothelial cells are usually translucent and not hyperchromatic, and there is rarely a coarse chromatin pattern. On the other hand, in positive specimens during or after local mitomycin therapy, usually a number of tumor cells showing nuclear enlargement, hyperchromatic nuclei, coarse chromatin pattern, and/or increased nuclear-cytoplasmic ratio are found beside the atypical cells changed by mitomycin.

Aged↗
PubMed1988

[Hormone receptor determination in breast cancer using the dextran- coated charcoal method and monoclonal antibodies: correlation with cytomorphologic grading].

In 129 cases, results from ER-ICA (Estrogen receptor immunocytochemical assay) applied to breast carcinoma biopsy smears and results from ER-EIA (Estrogen receptor enzyme immunoassay) applied to cytosols of breast carcinoma were compared to the results of ER(DCC), PR(DCC) and a cytomorphological grading. Using 500x magnification, the cases were graded visually in 7 groups, groups 1-4 without and groups 5-7 with nucleoli. Cases with high estrogen receptor values as determined by ER-EIA had the best chance of being detected also by the ER-ICA method. There is a relation between the visual nuclear grade from the Pappenheim stained specimens and ER-ICA and ER-EIA. The 48 cases without nucleoli had a mean ER-EIA-value of 100 fmol/mg (median = 59 fmol/mg). The 57 cases with nucleoli (groups 5-7) had a mean ER-EIA value of 37 fmol/mg (median = 14 fmol/mg). For 28 cases with prominent or multiple prominent nucleoli (groups 6-7) the mean ER-EIA value was only 15 fmol/mg (median = 5 fmol/mg). With increasing ER-EIA values we found decreasing average nuclear grades: 31 cases ER-EIA less than 10 fmol/mg, mean nuclear grade = 5.4; 34 cases ER-EIA greater than or equal to 10 less than 50 fmol/mg, mean nuclear grade = 4.6; 20 cases ER-EIA greater than or equal to 50 less than 100 fmol/mg, mean nuclear grade = 4.2; 19 cases ER-EIA greater than or equal to 100 fmol/mg, mean nuclear grade = 3.8. Our present data show clearly that there is a closer correlation of cytomorphology with ER-EIA than with ER(DCC) and PR(DCC). In the present study even ER-EIA alone correlated better with morphology than ER(DCC) and PR(DCC) taken together.

Antibodies, Monoclonal↗
PubMed1986

[Cytomorphological grading and hormone receptor status in breast carcinoma. Visual studies of smear preparations].

From 923 breast cancers sent in for hormone receptor determination, 745 diagnostically utilizable Pappenheim-stained biopsy smears at 500-fold magnification were classified into eight atypia groups (1-4 without nucleoli, 5-8 with nucleoli) visually in terms of the severity of the cellular malignancy criteria. The hormone receptor status was determined with the dextran-coated charcoal method. Values from 10 fmol/mg estrogen receptor (ER) and (or) progesterone receptor (PR) content were designated as receptor-positive. There was a decrease in the proportion of receptor-positive results with increasing degree of atypia from 97% in group 2 (cases with only small nuclei without nucleoli) to 37% in group 7 (cases with multiple prominent nucleoli). When the average atypia values of subgroups were compared, the highest values were found for the 222 receptor-negative carcinomas. The marginally receptor-positive values were on average between the receptor-negative and the receptor-positive cases with high values. Both the low-ER and the low-PR have more pronounced criteria of malignancy compared to the respective high-receptor reference group.

Biopsy↗
PubMed1986

Investigation of the visual cytoscreening of conventional gynecologic smears. II. Analysis of eye movement.

The perception of visual information in cytoscreening was studied: eye movements were recorded while the cytotechnologist was screening cervical smears by means of a projection screen. Four phases of eye movement could be distinguished: small, aimless movements during the stage movement; a latency period with a duration of about 180 milliseconds; saccadic movement to the position of an object; and fixation on an object. These components explain the two-phase behavior of cytoscreening found in our previous investigations of the stage movement. Visual perception during the period of latency was found to be the most important since only those objects that are recognized by peripheral vision during this period can trigger the necessary saccadic movement before fixation takes place. The scanpath of search in the stationary field of view is determined by the conspicuousness of the objects; the main features of conspicuousness are size and contrast. Even with the comparatively small fields of view (24 degrees and 29 degrees in diameter) used in these experiments, it was found that the detection threshold of peripheral vision increases towards the margin of the field of view. This raises the question of whether the use of large-field binoculars (with 40-degree visual angles) may cause higher false-negative rates for samples with only a few atypical cells.

Cytodiagnosis↗
PubMed1986

Investigation of the visual cytoscreening of conventional gynecologic smears. I. Analysis of slide movement.

In order to elucidate the process of visual cytoscreening, graphic and electronic recordings of the stage movements in visual screening of conventional gynecologic smears were carried out. More than 400 recordings have been evaluated. The screening consisted of alternating movements, with a mean duration of 180 milliseconds, and stops of about 230 milliseconds. Variations of the screening pattern due to the specimen diagnosis were hidden behind the rather obvious individual behavior and reactions to inhomogenity of material distribution. The detection threshold was found to vary with the diagnostic situation. A lowering of the detection threshold was especially reflected by an increase of the overlap in screening direction and an increased number of fields of view with stop times of more than 350 milliseconds. A substantial part of the specimen was only seen during movements; the fraction of the specimen area covered during the stops was found to vary between 41% and 93% for screenings in the daily routine work.

Evaluation Studies as Topic↗
PubMed1985

[Puncture cytology of the breast: correlation of visual and image analysis studies with hormone receptor status].

It is possible to predict to some extent the hormone receptor status of carcinomas of the breast via cytomorphology of fine needle biopsy specimens. In most cases the cytologically highly differentiated carcinomas are receptor-positive and the poorly differentiated ones receptor-negative if the cases are arranged in the sequence of increasing conspicuousness of cellular criteria of malignancy. Since visual microscopic examination is subjective by nature, quantification was carried out by means of high-resolution image analysis using Pappenheim stained slides. The quantitative image analysis grading system basing on this method proved to be even more efficient than visual diagnosis.

Biopsy, Needle↗
PubMed1983

[Registration of slide movement in conventional cytodiagnosis - relevance for automated cytodiagnosis].

Registration of slide-movements in conventional gynecological smears - its relevance for automated cytology - The information contained in conventional cytologic smears can only be obtained by means of a very scrutinizing scanning of the slide. This is one of the reasons, why people are interested in automated cytology. In the present study slide movements during 216 visual screenings of conventional gynecologic smears were graphically and electronically recorded. The recordings show alternating movements and stops. The time of stops shows a high variation with a mean value of about 0,3 seconds. The moving times are mostly below 0,2 seconds. The relation of total stop times to total movement times is in most cases between two and three. The percentage of total stop times, the total screening time, the relation of stop times to movement times and the number of microscopic fields evaluated while standing rise in difficult specimens. There are obvious differences between the screening patterns of different cytotechnologists. An analysis of the recordings concerning the number of stops shows that even in smears which are screened very carefully a considerable percentage of the smear is not seen during the stops. The pattern of mechanical slide movements allows conclusions about the "data acquisition" by the human cytoscreener.

Autoanalysis↗
PubMed1983

Effect of the special properties of monolayer cell preparations for automated cervical cytology on visual evaluation and classification. With an estimation of the number of cells required to be screened.

Monolayer preparations used in cell image analysis show some peculiarities as compared with conventional cytologic smears, such as homogeneous distribution of cells, distinct appearance of cells and a reduced number of background elements. However, for use in gynecologic cytology, monolayer preparations must be accessible to visual examination and classification. To investigate the consequences of the special features of these preparations on the strategy of visual evaluation, we estimated the minimum number of cells needed for a diagnostic decision. Cell counts were made of gynecologic monolayer preparations from 50 women with no suspicion of malignancy and 50 women with invasive squamous-cell carcinoma of the uterine cervix and its precursors. Our results showed that the more serious the lesion, the lower the number of cells needed for a diagnostic decision. The highest mean values of numbers of cells needed for an effective diagnosis were estimated in cases of mild and moderate dysplasia (734 cells) and in non-suspicious cases (731 cells). The number of cells needed did not exceed 1,700 in any case. The false-negative and false-positive rates were 6% and 2%, respectively, including the cases of mild to moderate dysplasia.

Carcinoma, Squamous Cell↗
PubMed1982

[Psammoma bodies in cervical smears (author's transl)].

Two cases with the finding of psammoma bodies in the cervical smear are reported. The first patient was 44 years old and without clinical evidence of disease. A routine Papanicolaou smear showed multiple psammoma bodies either free or surrounded by an epithelium without striking atypia. The cytologic findings were reported as suspicious of ovarian or endometrial adenocarcinoma. Histologically a serous papillary cystadenocarcinoma was found. Three years later there is no sign of recurrence. The second patient was 72 years old and presented pleural and ascitic effusions, with tumour cells of adenocarcinoma. The cervical smear showed psammoma bodies and tumour cells of adenocarcinoma. She died without histological examination.

Adenocarcinoma↗
PubMed1979

[Evaluation of cytophotometric DNA-measurements of samples from the uterine cervix (author's transl)].

Results of DNA-cytophotometric studies of samples from the uterine cervix are evaluated in normal cervical epithelia, inflammation, dysplasia, carcinoma in situ, and invasive squamous cell carcinoma. As to their significance for cytology-automation the results suggest an arbitrary DNA-value in the range of 4.5 to 5 c by which precancerous lesions and invasive squamous cell carcinoma can be distinguished from benign squamous epithelia. Possibly a higher DNA-value is acceptable if larger cell populations are analyzed.

Carcinoma, Squamous Cell↗