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Objective: To establish if measurements of DNA ploidy could be used to assist cytopathologists and cytotechnologists in population based cervical cancer screening programs in countries where manually reading the slides is impossible due to the lack of sufficient skilled cytotechnologists. The goal of such program is to identify only clinically significant lesions, i.e. those where a clinical intervention to remove the lesion is required immediately. Study Design: A total of 9905 women were enrolled in the study. Cervical samples were taken with a cervix brush that was then placed into a fixative solution. The cells were separated from mucus by mechanical and chemical treatment and then deposited onto microscope slides by a cytocentrifuge. Two slides were prepared from each case; one slide was stained by Papanicolaou stain for manual cytology examination, while the other slide was stained by a DNA specific stain. The latter slide was used to determine the relative amount of DNA in the cell nuclei. Results: A total of 876 women were followed by colposcopy examination where biopsies were taken from the visible lesions or from suspicious areas and histopathology diagnosed 459 as normal or benign cases, 325 as CIN1, 36 as CIN2, 25 as CIN3/CIS, and 31 as invasive cancer. Of these 876 cases, manual cytology called 655 normal or ASCUS, 197 as LSIL, 16 cases as HSIL, and 8 as cancer. DNA measurements found 704 cases having no cells with DNA greater than 5c, 98 cases where there were 1 or 2 cells having DNA amount greater than 5c, and 74 cases where there were 3 or more cells having DNA amount greater than 5c. If manual cytology were to be used to refer all cases of HSIL and cancer to colposcopy and biopsy, 23 lesions that had to be removed would have been discovered (2 CIN2, 11 CIN3/CIS, and 10 cancers), for a sensitivity of 25.0±5.2% at specificity of 99.9±0.1%. If DNA assisted cytology were to be used instead, and all cases having 3 or more cells with DNA amount greater than 5c were to be referred to colposcopy and biopsy, then 50 lesions that had to be removed would have been discovered (10 CIN2, 15 CIN3/CIS and 25 cancers) for the sensitivity of 54.3±6.2% at specificity of 96.9±0.6%. Conclusions: The study suggests that screening for high grade cervical neoplastic lesions and cervical cancer by DNA assisted cytology could be implemented with minimal use of skilled cytotechnologists, at least in those countries where it would be difficult to introduce population based screening for cervical cancer due to the lack of availability of such skilled cytotechnologists.

Objectives: The common subtypes of renal tumors are conventional or clear cell carcinoma, papillary carcinoma, chromophobe carcinoma and oncocytoma. Each subtype has its distinct histogenesis and clinical evolution. DNA ploidy is viewed as a marker of gross genomic aberrations. The aim of this study is to evaluate the DNA ploidy in the common subtypes of renal tumors to increase our understanding of renal tumor biology and to broaden clinical application of DNA ploidy. Methods: 38 renal tumor samples (13 clear cell RCCs, 12 papillary RCCs, 7 chromophobe RCCs, and 6 oncocytomas) were studied. Five biopsies of different parts of each fresh tumor were subjected to a flow cytometric analysis of DNA ploidy. Results: All tumors except one papillary RCC generated interpretable DNA histograms. Flow cytometric analysis of oncocytomas showed the diploid pattern (29/30 frequencies) while the chromophobe RCC never showed the diploid pattern (0/55 frequencies) (p < 0.01). 3/7 chromopbobe RCCs possessed the hypodiploid stemline. The hypodiploid stemline appeared neither in conventional RCCs (0/63 frequencies) nor in papillary RCCs (0/50 frequencies). The diploid pattern was dominant in conventional and papillary RCCs. 10/13 (76.9%) of clear cell RCCs and 9/11 (81.8%) of papillary RCCs possessed a homogeneous DNA ploidy pattern while only 1/7 (14.3%) has a homogeneous DNA ploidy pattern. 6/7 chromophobe RCCs had multiple aneuploid stemlines. Conclusions: Flow cytometric analysis reveals that conventional and papillary RCCs are more homogeneous than chromophobe RCC. Each subtype of renal tumors possesses a specific DNA ploidy pattern. The analysis of DNA ploidy is useful for the differentiation of common subtypes of renal tumors in morphologically difficult cases.

Background: Confocal Laser Scanning Microscopy (CLSM) provides the opportunity to perform 3D DNA content measurements on intact cells in thick histological sections. So far, sample size has been limited by the time consuming nature of the technology. Since the power of DNA histograms to resolve different stemlines depends on both the sample size and the coefficient of variation (CV) of histogram peaks, interpretation of 3D CLSM DNA histograms might be hampered by both a small sample size and a large CV. The aim of this study was to analyze the required CV for 3D CLSM DNA histograms given a realistic sample size. Methods: By computer simulation, virtual histograms were composed for sample sizes of 20000, 10000, 5000, 1000, and 273 cells and CVs of 30, 25, 20, 15, 10 and 5%. By visual inspection, the histogram quality with respect to resolution of G0/1 and G2/M peaks of a diploid stemline was assessed. Results: As expected, the interpretability of DNA histograms deteriorated with decreasing sample sizes and higher CVs. For CVs of 15% and lower, a clearly bimodal peak pattern with well distinguishable G0/1 and G2/M peaks were still seen at a sample size of 273 cells, which is our current average sample size with 3D CLSM DNA cytometry. Conclusions: For unambiguous interpretation of DNA histograms obtained using 3D CLSM, a CV of at most 15% is tolerable at currently achievable sample sizes. To resolve smaller near diploid stemlines, a CV of 10% or better should be aimed at. With currently available 3D imaging technology, this CV is achievable.

This analysis of DNA‐ploidy heterogeneity in advanced gastric carcinomas is consistent with the hypothesis of the emergence of a single aneuploid cell clone as a crucial mechanism in the progression from early gastric carcinoma to advanced gastric cancer. The prognostic value of DNA‐ploidy in gastric cancers has been a matter of controversy. Tumour DNA‐ploidy heterogeneity, the presence within the same tumour of multiple stemlines differing in DNA content, has been described in various tumours including gastric cancers. The occurrence of such heterogeneity has been accepted as an explanation for the divergent DNA‐ploidy results in this type of tumours. A previous study of early gastric cancers suggested that in pure diploid superficial carcinomas, genetic instability might lead to a cell clone which has undergone a ploidy shift and is more aggressive. If so, this would initially result in DNA‐ploidy heterogeneity. Proliferative dominance of the aneuploid clone could eventually evolve to a homogeneous aneuploid tumour. In order to test this hypothesis, we studied DNA‐aneuploidy and DNA‐ploidy heterogeneity in advanced gastric carcinomas. We performed DNA cytophotometry on multiple samples collected from 16 advanced gastric carcinomas and found 15 DNA‐aneuploid tumours (94%) and one diploid tumour. Multiple DNA‐stemlines were found in 4 cases (26%). Analysis of proliferative activity performed on the same samples revealed higher proliferation rate in DNA‐ploidy homogeneous tumours than in aneuploid heterogeneous tumours. Heterogeneous tumours did not overexpress p53. These results confirm that DNA‐aneuploidy is frequent in advanced gastric cancer and demonstrate that a majority of these aneuploid tumours are not DNA‐ploidy heterogeneous. Furthermore, the higher proliferative activity in homogeneous‐aneuploid carcinomas and their more frequent overexpression of p53 support the hypothesis that in gastric cancer tumour progression implies the development of a dominant and more aggressive (higher proliferative activity, p53 overexpression) aneuploid cell clone.

Purpose: Leiomyosarcomas (LMS) of deep and superficial tissues were examined to identify prognostic markers explaining their different biological behaviour and to define differences between cutaneous and subcutaneous LMS. LMS and leiomyomas (LM) of the skin were compared to and consistent differences that could aid in the (sometimes difficult) diagnosis.Patients: Material was obtained from 27 patients with a deep LMS, 14 with a superficial LMS, and 21 with a LM.Methods: Proliferation markers (mitotic and Ki-67 indices), DNA ploidy, size, grade, and the amount of apoptosis were studied. Statistical analysis was performed and survival curves were constructed by the Kaplan-Meier method and compared by the log-rank test.Results: Superficial LMS were smaller than deep LMS (p < 0.05), and the overall survival of patients with a superficial LMS was better than with a deep LMS (p < 0.05).Within the group of superficial LMS only entirely subcutaneous, and not cutaneous tumors metastasized.No differences were found in the other examined parameters. Proliferation and apoptotic indices were significantly higher in superficial LMS compared to superficial LM.Discussion: The difference in clinical outcome between patients with a superficial and deep LMS, seems to be related to site and size.The metastatic potential of subcutaneous LMS, however, seems to be related to location alone and not to size.The amount of apoptosis and proliferation can be used as additional criteria in the differentiation between superficial LMS and LM.

Background. Heterogeneity of prostate carcinoma is one of the reasons for pretreatment underestimation of tumor aggressiveness. We studied tumor heterogeneity and the probability of finding the highest tumor grade and DNA aneuploidy with relation to the number of biopsies. Material and methods. Specimens simulating core biopsies from five randomly selected tumor areas from each of 16 Böcking’s grade II and 23 grade III prostate carcinomas were analyzed for tumor grade and DNA ploidy by flow‐ and fluorescence image cytometry (FCM, FICM). Cell cycle composition was measured by FCM. Results. By determination of ploidy and cell cycle composition, morphologically defined tumors can further be subdivided. Heterogeneity of tumor grade and DNA ploidy (FCM) was 54% and 50%. Coexistence of diploid tumor cells in aneuploid specimens represents another form of tumor heterogeneity. The proportion of diploid tumor cells decreased significantly with tumor grade and with increase in the fraction of proliferating cell of the aneuploid tumor part. The probability of estimating the highest tumor grade or aneuploidy increased from 40% for one biopsy to 95% for 5 biopsies studied. By combining the tumor grade with DNA ploidy, the probability of detecting a highly aggressive tumor increased from 40% to 70% and 90% for one and two biopsies, respectively. Conclusion. Specimens of the size of core biopsies can be used for evaluation of DNA ploidy and cell cycle composition. Underestimation of aggressiveness of prostate carcinoma due to tumor heterogeneity is minimized by simultaneous study of the tumor grade and DNA ploidy more than by increasing the number of biopsies. The biological significance of coexistent diploid tumor cell in aneuploid lesions remains to be evaluated.

Backgound: Epithelial cell proliferation activity has been reported both to be unaltered and increased inHelicobacter pylori(H. pylori) associated chronic gastritis. The proliferation rate decreased followingH. pylorieradication, but results are controversial whether this change is dependent on the success of eradication. We compared the cell proliferation activity ofH. pyloripositive and negative gastric epithelial biopsies in chronic gastritis with and without intestinal metaplasia (IM) and gastric cancer by the expression of proliferation cell nuclear antigen (PCNA) and Tv image cytometry, and assessed the effect ofH. pylorieradication on the cell proliferation rate in the gastric epithelium.Methods: Brush smears and antral biopsies were taken from 70 patients (42 men, 28 women, mean age 58 ± 15 y.o.) on routine endoscopy. Patients were divided into four groups according to the histology; normal epithelia (n=10), chronic gastritis without IM (n=24), chronic gastritis with IM (n=20), and gastric carcinoma (n=16). Thirty‐three patients wereH. pyloripositive, and success of eradication was controlled in 24 cases. Cell proliferation was measured by immunohistochemistry using PCNA labeling index (LI) and by Tv image cytometry evaluating 12 morpho‐ and densitometric parameters of each nuclei and 6 additional parameters of each smear.Results: PCNA LI, DNA index and S + G2 ratio were all higher in chronic gastritis than in the normal epithelium, and were further increased in carcinoma. The lower PCNA LI observed in chronic gastritis with IM corresponds to the lower S phase ratio determined by Tv image analysis. InH. pyloripositive cases, the proliferation activity was 69.3 ± 13.05% prior to the eradication and it decreased to 55.8 ± 23.31% after the successful eradication therapy. When immunohistochemistry was compared with Tv image cytometry, PCNA LI significantly correlated with the percentage of cells in G1 phase (r=−0.415) and S phase (r=0.385), Integrated Optical Density mean (r=0.598), density maximum (r=0.608), surface (r=0.670), layers (r=0.638), diameter minimum (r=0.619), diameter maximum (r=0.730) and perimeter (r=0.501), respectively (p< 0.05).Conclusions: Epithelial cell turnover is increased in chronic gastritis with or without IM, and in gastric carcinoma. The lower PCNA LI observed in chronic gastritis with IM corresponds to the lower S phase ratio determined by Tv image analysis. Cell proliferation decreases after successfulH. pylorieradication. Both methods proved to be reliable for the determination of epithelial cell proliferation.

The aim of the present study is to propose alternative automatic methods to time consuming interactive sorting of elements for DNA ploidy measurements. One archival brain tumour and two archival breast carcinoma were studied, corresponding to 7120 elements (3764 nuclei, 3356 debris and aggregates). Three automatic classification methods were tested to eliminate debris and aggregates from DNA ploidy measurements (mathematical morphology (MM), multiparametric analysis (MA) and neural network (NN)). Performances were evaluated by reference to interactive sorting. The results obtained for the three methods concerning the percentage of debris and aggregates automatically removed reach 63, 75 and 85% for MM, MA and NN methods, respectively, with false positive rates of 6, 21 and 25%. Information about DNA ploidy abnormalities were globally preserved after automatic elimination of debris and aggregates by MM and MA methods as opposed to NN method, showing that automatic classification methods can offer alternatives to tedious interactive elimination of debris and aggregates, for DNA ploidy measurements of archival tumours.

Flow Cytometry (FC) has been incorporated into cancer research in relation to its prognostic value together with histological parameters and TNM stages. We have studied by means of FC the cell cycle of 132 samples from male patients with Squamous Cell Lung Carcinoma (SQCLC). All of the patients received curative surgery and the clinical follow-up was 60 months. The clinical and cytometric parameters were evaluated in order to predict the patients’ outcome. The presence of tumoural recurrence and the tumoural stage showed statistical significance associated with survival. The multivariant analysis reveals radiotherapy (p= 0.004) as protective variable and the high S-phase fraction (SPF) (p= 0.001) and stage IIIA (p= 0.012) as risk factors. The SPF appears as an independent prognostic factor for overall survival time. We can build a prognostic index representative of different prognostic groups, which allows us to improve the individual monitoring of these patients.

DNA flow cytometry has been extensively studied in female breast carcinoma. However, there is limited data evaluating DNA ploidy in male breast cancer. In order to further assess the prognostic significance of DNA ploidy in male breast carcinoma, we retrospectively reviewed 55 cases (52 patients) of histologically proven male breast carcinoma treated at our institution from January 1971 through January 1992. Of the 55 cases, 32 paraffin-embedded blocks were available for DNA flow cytometry analysis. As of June 1993, median follow-up is 7.0 years. In the overall population of 55 cases, univariate analysis identified TNM stage, tumor size, and nodal status as significant prognostic indicators of overall survival and disease-free survival. In the 32 cases available for DNA flow cytometry, both local recurrences and distant metastases were more frequent in the aneuploid population. Univariate analysis revealed DNA ploidy to be a significant prognostic factor for local recurrence-free survival and distant metastasis-free survival. DNA ploidy correlated significantly with stage at diagnosis (p =.04), tumor size (p =.04) and nodal status (p =.02). In a multivariate analysis of 26 patients on whom all data were available (DNA ploidy, tumor size, clinical stage and nodal status), DNA ploidy was an independent predictor of disease-free survival (p =.05). In this retrospective analysis, we conclude that DNA ploidy has prognostic significance in male breast carcinoma.