The diagnostic significance of nuclear deoxyribonucleic acid measurement in automated cytology.

Flow cytometric analysis of cytologic samples from four different organs shows that nuclear DNA content of malignant cell populations depends to a large extent on organ of origin of the tumor. This fact must be considered in planning screening systems.

DNA ploidy and protein synthesis in squamous cell carcinoma cell lines of the head and neck.

Aneuploidy as abnormal nuclear DNA content, is considered almost positive evidence of malignancy. In this study three diploid and three aneuploid squamous cell carcinoma (SCC) cell lines were examined for DNA content by flow cytometry. The DNA indices of the SCC cell lines were found to range from 1.0 to 2.1. The mitotic activity of the diploid cell lines was 1.6 times higher and the cells were smaller than aneuploid cells. To find a molecular basis for these differences, the pattern of the de-novo synthesized proteins was analyzed by means of [35S]methionine incorporation, electrophoresis, and autoradiography. In all aneuploid SCC cell lines tested in this experiment, the increase of nuclear DNA content is associated with the synthesis of a novel protein with a molecular mass of approximate 55 kDa as well as with altered synthesis rates of two preexisting proteins (50 kDa and 100 kDa). For determination of the amino acid uptake in diploid and aneuploid cells, the accumulation of [35S]methionine was measured as a function of time by liquid scintillation counting. No significant difference was found in the uptake rate between diploid and aneuploid cells with the same protein content. However, discrepancies were revealed when equal numbers of cells with different DNA index were used, suggesting, that protein turnover is different in diploid and aneuploid SCC cells.

The diagnostic significance of nuclear DNA measurement in cytologic smears of benign and malignant gastric lesions.

Gastric mucosa was obtained from 126 patients by endoscopic biopsy and subsequent cell brushing for histological, cytological and DNA cytophotometric studies. 23 cases were carcinomatous. DNA histogram evaluation for each case was carried out with special consideration of the position of the DNA stem line and the scatter of the measured DNA values. Additionally, DNA distribution characteristics were established for clinical or cytological diagnostic groups. By ascertaining relative mean ploidy values (U values) and relative frequency of euploid and polyploid values (Z values) in the sample populations, cell nuclear DNA determination was used as a criteria for differentiating between benign and malignant alterations of the stomach. The results allow optimistic prognosis concerning the use of cell nuclear DNA content as a significant, though not as the only measuring factor in automated diagnostic procedures.

The diagnostic significance of flow cytometric nuclear DNA measurement in gastroscopic diagnosis of the stomach.

Cell material obtained from 161 patients by gastroscopic aided brushing was compared cytologically and DNA flow cytometrically and evaluated by mathematical discriminant analysis. Whereas all but one of the cytologically confirmed malignant cases were also positive (malignant) in flow cytometry, the DNA determination failed in 6 of the 19 cytologically suspicious cases, having been classified as negative (benign) by cytometry. Out of all cytologically unequivocal malignant and suspected cases, 18% (7 cases) were false-negative in flow cytometry. The false-positive rate was 39% (47 cases). 5% of the material was classified as inadequate for diagnosis (8 cases) by flow cytometry. The false-negative rate of flow analysis in cytologically suspicious cases is apparently caused by a less pronounced increase of DNA content in the cell nuclei of these cases. Reactive gastric mucosa alterations such a inflammations, erosions or ulcers exhibited increased cell nuclear DNA. According to these results, DNA determination can be used as an automated diagnostic procedure for tumour detection only in combination with other measuring criteria.

The diagnosis of endometrial carcinoma by means of jet wash and DNA flow-through cytophotometry.

Flow-through cytophotometric determination of nuclear DNA content on jet wash material from the endometrium was employed in the diagnosis of endometrial carcinoma. One hundred and thirty cases were studied. In comparison to results from cytodiagnosis, flow-through photometry yielded a false negative rate of 31.6% and a false positive rate of 42.2%. The false negative findings resulted in part from the small relative frequency of atypical cells in a mixed population of normal and atypical cells in certain cases. Besides this, we often found carcinomas with a diploid DNA stem line, which could not be distinguished cytophotometrically from normal corpus endometrium (Sandritter, 1952; Atkin et al., 1959; Hustin, 1976). The flow-through photometrically false positive findings may have resulted either from cell aggregates or from a nuclear DNA content elevated over the diploid value in proliferating cells (D. Wagner et al., 1968; D. Wagner and Richard, 1968). The observed false negative and false positive rates demonstrate that flow-through photometric determination of nuclear DNA content is unsuitable for the diagnosis of endometrial carcinoma.

Malignant rhabdoid tumor. A morphological and flow cytometric study.

Sixteen cases of malignant rhabdoid tumor (MRT) were studied by conventional light microscopy, immunohistochemistry, electron microscopy and flow cytometry. The age of the 16 patients varied from two months to 25.9 years. There were 11 males and five females. Eleven tumors were located in the kidney. The remaining five were found in the chest wall (n = 2) and the head and neck (n = 3). Particular histopathological findings included myxoid, pseudoalveolar and hyalinized areas. By immunohistochemistry, 15/15 cases stained positively for vimentin, 9/14 for cytokeratin, 6/15 for desmin, 9/14 for epithelial membrane antigen (EMA), 10/14 for neuron specific enolase (NSE) and 10/15 for protein S-100. Stains for neurofilaments, myoglobin and Ulex europaeus aggl. I (UEA I) were negative. The characteristic finding by electron microscopy in three cases were large numbers of intermediate filaments arranged either randomly or in concentric whorls. None of the 11 cases studied revealed aneuploid DNA stem lines as determined by flow cytometry. Of the 16 patients 12 died, one is living with disease and three are living without evidence of disease. Postoperative treatment consisted of chemotherapy, in some cases combined with radiotherapy. Two patients developed a medulloblastoma in addition to a renal and extrarenal MRT, respectively. Our findings demonstrate that MRT may present more histopathological patterns than hitherto recognized. In addition, they show that MRT may express a wide range of antigenic "markers", similar to epithelioid sarcoma with which it may be confused on cytological grounds. Despite aggressive postoperative chemotherapy prognosis is still poor.

Cytophotometric studies in suspicious cervical smears.

Papanicolaou stained smears of various cervical lesions diagnosed as "suspicious" by routine cytology were reviewed with regard to different cell types leading to this diagnosis. The smears were then submitted to Feulgen hydrolysis and redyed by Acriflavin-SO2 for fluorescence-cytophotometry. In nine of 14 cases measured, the DNA content of all types of "suspicious" cells was increased with DNA modes at euploid levels of 2 n, 4 n and 8 n indicating that the "suspicious" cells in those cases are polyploid. However, in five cases aneuploid DNA-distribution patterns were found similar to those observed in carcinoma in situ or severe dysplasia. Since polyploidization may be considered as a cellular response to higher functional requirement (i.e. inflammation or regeneration) a "suspicious" cervical smear with a polyploid DNA-distribution pattern may reverse to normal cervical epithelium after normal conditions are restored. However, a "suspicious" smear with an aneuploid DNA-distribution pattern should be considered more seriously as being related to a precancerous lesion requiring immediate surgical treatment.

Differential diagnosis between follicular adenoma and follicular carcinoma of the thyroid by nuclear DNA determination.

Distinction between follicular adenomas and follicular carcinomas of the thyroid using fine needle aspiration cytology presents a problem. We investigated whether Feulgen photometric nucear DNA determination could offer additional, usable information for differential diagnosis. Since both diploid carcinomas and polyploid, widely scattered adenomas and nodular colloid goiter are seen, we found that nuclear DNA determinations proved useful in differential diagnosis only for occasional special cases.

The false negative rate in cervical cytology. Comparison of monolayers to conventional smears.

OBJECTIVE: To compare cervical monolayers prepared by a density gradient technique to conventional smears. STUDY DESIGN: The study evaluated 2,863 patient samples. After conventional smears were prepared, the residual samples (collected in preservative fluid) were processed by the monolayer preparation system, which disaggregates the cells, removes nonclinical debris and layers the diagnostic material onto a microscopic slide. Slides were screened in Germany and the United States in masked studies. RESULTS: In the U.S. study, the false negative rate for the conventional smears was 9.4% when endocervical components were present and 16.7% when absent. The false negative rate for the monolayer preparation was 4.0% when endocervical components were present and 5.7% when absent. A comparison of the diagnostic results showed that the monolayer made possible the detection of 48 cases of low grade disease or higher that were not found on the conventional smear. The German study was independent but used the same samples. The results, although based upon the Papanicolaou classification, were similar. CONCLUSION: Cervical samples that are preserved in a liquid suspension and prepared using the density gradient monolayer technology have many advantages over conventional cervical cytologic smear preparations. The quality of cell preservation and presentation is superior. Elimination of obscuring material, homogeneity of the sample and standardized quality work together to produce preparations that can be effectively and reliably screened by cytotechnologists. These preparations should greatly enhance the reliability of machine-based screening in the future.

[Significance of digital examination in early diagnosis of prostate carcinoma (author's transl)]. / Die Aussagekraft des rektalen Palpationsbefundes bei der Früherkennung des Prostatakarzinoms

Digital palpation of the prostate is not suitable for positive differentation between benign and malignant lesions of the prostate. Whenever a conspicuous finding is observed during a physical examination of the prostate a fine needle aspiration cytology is mandatory for eluidation of the disease. This procedure is simple and inexpensive, has a low rate of complications and high diagnostic validity.