The application of flow cytometric DNA analysis in detecting the presence of malignant cells in ovarian carcinoma peritoneal fluids

Heparanase expression: a potential ancillary diagnostic tool for distinguishing between malignant cells and reactive mesothelium in body cavity effusions

OBJECTIVE

Heparanase, an endoglycosidase that cleaves heparan sulphate, is frequently expressed in carcinomas and was suggested to play a role in cell invasion and metastasis. We investigated whether heparanase expression may serve as a reliable marker to discriminate benign mesothelial cells from malignant cells shed into body cavities.

METHODS AND RESULTS

Cytological smears of effusions from 51 hospitalized patients were immunostained for heparanase. Strong immunoreactivity was noted in 35 of 40 (88%) carcinoma samples and in all three malignant mesothelioma cases. Only rare (<3%) reactive mesothelial cells were noted showing a faint negligible staining. Specificity was 100%, sensitivity 88%, and positive and negative predictive values were 100% and 89% respectively.

CONCLUSIONS

Our results suggest that heparanase may be of value as a complementary component in a diagnostic panel of markers, contributing to its reliability and accuracy.

Detection of tumor cells in body cavity fluids by flow cytometric and immunocytochemical analysis

Measurement of electronic volume versus DNA content of nuclei can be used to discriminate between normal and malignant cells. Epithelial membrane antigen immunocytochemistry (EMA-ICC), a helpful ancillary test in body cavity fluids, is not universally accurate for detecting malignancy in effusions. The current study was undertaken to determine if multiparametric flow cytometry (based on simultaneous analysis of light scatter, nuclear volume, DNA, and nuclear protein content) in combination with (EMA-ICC) could be used for the detection of malignant cells in peritoneal and pleural fluids. We studied 130 body cavity fluids (68 peritoneal and 62 pleural fluids) by conventional cytology and multiparametric laser flow cytometry. EMA-ICC was performed using EMA antibodies and L-SAB detection system (DakoCytomation, Carpinteria, CA). EMA-ICC had significantly higher sensitivity than conventional cytology (79% versus 59%, P = 0.016) and ploidy (79% versus 38%, P = 0.001). Cytology had significantly higher specificity than ploidy (97% versus 82%, P = 0.012). The differences in specificity between EMA-ICC and ploidy (87% versus 82%, P= 0.607) or EMA-ICC and cytology (87% versus 97%, P = 0.109) were not statistically significant. However, assuming serial testing, sensitivity increased significantly for the combinations of cytology and EMA-ICC (79.4%, P = 0.016) and cytology and ploidy (73.5%, P = 0.004) as compared to cytology alone (58.8%). Also, the combination of cytology and ploidy had a higher sensitivity than ploidy alone (73% versus 38%, P < 0.0001). However, the sensitivity associated with the three tests used in serial (85.3%) was not significantly different from the sensitivities corresponding to the combination of cytology and EMA-ICC (79%) or cytology and ploidy (73%). Multiparametric flow cytometry utilizing high resolution DNA, nuclear volume, protein measurement, and ICC, in combination with cytomorphology, may be a valuable tool for rapid identification of malignant cells in body cavity fluids.

Flow cytometry in the diagnosis of peritoneal carcinomatosis

OBJECTIVES

Peritoneal carcinomatosis is the second major cause of ascites. Because of its frequency and poor prognosis, it is important to establish an accurate diagnosis. The aim of this study was to analyze the use of a DNA index, detemined by flow cytometry in the differential diagnosis of ascites, and to compare it to the cytopathological examination.

METHODS

A prospective analysis was carried out on 67 patients (39 female, 28 male; mean age, 53+/-14 yr [range, 5-82]) with ascites of various etiologies. Peritoneal carcinomatosis was detected in 21 patients, whereas in 46 the ascites was of noncarcinomatosis origin.

RESULTS

The sensitivity of the cytopathological examination for the diagnosis of peritoneal carcinomatosis was 42.9%, and the specificity was 100%. The mean DNA index determined by flow cytometry was similar for peritoneal carcinomatosis and noncarcinomatosis patients, being 1.28 versus 1.01, respectively, in the preparations without control lymphocytes and 1.28 versus 1.04, respectively, when control lymphocytes were added. The sensitivity of DNA index cytometry was 57.1% and specificity, 93.5%. The combined use of the DNA index and cytopathological examination did not show an advantage over the use of any of the tests individually, although the DNA index was able to detect half of the cases of peritoneal carcinomatosis in which cytopathological examination was negative. Although the sensitivity was higher when the parameters were associated, the DNA index did not offer a statistically significant advantage over the use of cytopathological examination alone, which in turn had higher specificity.

CONCLUSION

The DNA index presented lower sensitivity for the diagnosis of peritoneal carcinomatosis when used alone, showing no advantage over conventional cytopathological examination. However, the DNA index was able to detect 50.0% of peritoneal carcinomatosis cases whose conventional cytopathological examinations were negative, and could be valuable in these situations.

Diagnostic value of a second generation CA 15-3 antibody to detect adenocarcinoma in body cavity effusions

BACKGROUND

Detecting malignant cells in body cavity effusions can be diagnostically challenging. Several monoclonal antibodies have been studied to improve the diagnostic yield of effusion cytology but without widespread acceptance. The CA 15-3 antibody has demonstrated high sensitivity but limited specificity for breast carcinoma in surgical pathology. A second generation CA 15-3 antibody has been developed that has not been studied in serous effusions to the authors' knowledge. The authors examined this second generation CA 15-3 antibody for its diagnostic utility in detecting adenocarcinomas in this cytologic setting.

METHODS

Cell block material from 114 cases of unequivocally benign or malignant body cavity effusions were studied. Slides were stained for CA 15-3 by using the avidin-biotin complex method. The percentage of cells exhibiting strong staining was estimated both for breast carcinoma and for all adenocarcinomas as a group. These results were compared with CA 15-3 staining exhibited by benign mesothelium.

RESULTS

CA 15-3 was expressed in at least 10% of tumor cells in 97% of breast carcinoma cases and in 90% of adenocarcinomas overall. The highest sensitivity was observed in carcinomas of the breast, ovary, and lung. Of 40 cases of benign mesothelium, only 4 (10%) were positive (P < 0.001). The sensitivity of CA 15-3 was 97% for breast carcinoma and 91% for adenocarcinomas overall. Specificity was 95% for breast carcinoma and 91% for adenocarcinomas.

CONCLUSIONS

CA 15-3 is an immunostain with high specificity and sensitivity for adenocarcinomas in cell block material from effusions. The antibody holds particular promise for detecting breast carcinoma. Cancer (Cancer Cytopathol)

FHIT protein is expressed in benign mesothelium and has no clinical value in detecting carcinoma in body cavity effusions

The fragile histidine triad (FHIT) protein is a suspected tumor-suppressor gene frequently expressed in adenocarcinomas of the lung and other organs. Its expression in benign mesothelium has not been reported. This study examined the expression of FHIT in mesothelium from benign body cavity effusions. FHIT expression was also examined in a diversity of malignant effusions to evaluate any value of the FHIT protein to discriminate carcinomas from benign mesothelium. Fifty-eight cases of benign and malignant effusions were immunostained using cell block material and two different antigen retrieval methods with the ABC method. Benign and malignant cases were scored for percentage of cells with strong immunoreactivity. Benign mesothelium exhibited strong immunoreactivity for the FHIT protein in 32 of 32 (100%) cases, with 26 of 32 (81%) cases having expression in at least 50% of cells. Seventeen of 21 (81%) cases of adenocarcinomas also exhibited the FHIT protein in at least 50% of tumor cells. FHIT expression was also noted in small numbers of other malignancies. The FHIT protein is expressed consistently in benign mesothelium as well as many types of adenocarcinomas. Immunostaining for this protein has no value in discriminating adenocarcinomas from reactive mesothelium.

Ras gene activation in malignant cells of human ovarian carcinoma peritoneal fluids

In this study, we showed, for the first time, the pattern of point mutations at codon 12 of the K-ras, H-ras and N-ras genes, using polymerase chain reaction and restriction fragment length polymorphism analysis in 47 malignant cytologic specimens of ovarian adenocarcinoma peritoneal fluids. Forty-seven % of the samples were found to carry a point mutation at codon 12 of K-ras gene. Also, 21 cystadenoma peritoneal fluids were used as control specimens for the detection of ras mutations. Fourteen % of these samples were found to carry a point mutation at codon 12 of the K-ras gene. The prevalence of K-ras gene mutations were statistically correlated with FIGO and surgical stage of the malignant specimens. Our data demonstrates that the K-ras gene mutations are mainly affected (47%) in the malignant cells of the peritoneal washings or ascites of women with ovarian adenocarcinomas and may have value for the early diagnosis and monitoring of these neoplasms.

Detection of chromosomal aberrations in tumor cells and tumor infiltrating lymphocytes by molecular cytogenetics in patients with gynecological cancer

Conventional cytogenetic studies of tumor cells from patients with breast or ovarian cancer have shown multiple chromosomal abnormalities including chromosomes 7, 12, and 17. This study was designed to analyze the cytogenetic features of tumor cells and tumor infiltrating lymphocytes (TILs) by using a combination of magnetic activated cell sorting (MACS) and fluorescence in situ hybridization (FISH). Tumor cell, peripheral blood (PB), and TIL samples from 37 patients (20 ovarian tumors, 13 breast cancers, 3 uterine sarcoma, 1 carcinoma of the filamentary tube) were analyzed for the presence of numerical aberrations of chromosomes 7, 12, and 17. All of the tumor cells showed a high frequency of numerical aberrations of chromosomes 7, 12, and 17, especially trisomies or tetrasomies. There was no statistically significant difference in the incidence of chromosomal abnormalities in tumor tissue and effusions, or between primary and relapsed disease in patients with breast or ovarian tumors. However, tumor cells from patients with solid metastatic disease had significantly higher numbers of aberrations of chromosome 7 in the primary tumor than in tumors from patients without metastases (P = 0.049), suggesting that chromosome 7 is frequently involved in the progression of disease. Monosomies and trisomies of chromosomes 7 and 12 also occurred at a low percentage of TILs without any statistically significant difference between primary and relapsed tumors. The presence of these aneuploidies might be responsible for treatment failures in the immunotherapy of gynecological cancer.

Flow cytometry in diagnostic cytology

Flow cytometry (FCM) is a useful adjunct to cytologic examination, because the quantitative biochemical information it provides complements the morphologic information gained during visual examination. It aids in the interpretation of bladder washings, and is particularly useful for the assessment of lymphoid lesions, whether they originate from fine-needle aspiration, cerebrospinal fluid, or effusions. Optimal use of FCM frequently requires assessment of more than one parameter; simultaneous use of cell differentiation markers and nuclear DNA quantitation is often significantly more useful than either alone. Despite the utility of FCM, however, the potential for future development appears to be limited. Improvements in image cytometry allow reasonable assessment of ploidy and S-fraction to be made from specimens prepared on glass slides. Multiparameter measurements may also be accomplished with imaging techniques, which allow the further advantage of visual identification of cells with equivocal morphologic changes. The development of artificial intelligence methods for use with imaging technology has also significantly exceeded that of FCM. Finally, image cytometry is often more useful for samples with few cells. Other challenges are posed by immunocytochemical methods which compete with flow cytometry as tools for assessment of proliferation. Given the relatively high cost of FCM instrumentation, survival of FCM as an ancillary technique in cytopathology will require further technical refinements to offset the advantages currently associated with image cytometry and immunocytochemistry.