Comparison between flow cytometry and image cytometry in ploidy distribution assessments in gynecologic cancer

Calibration-Aimed Comparison of Image-Cytometry- and Flow-Cytometry-Based Approaches of Ploidy Analysis

Ploidy analysis is the fundamental method of measuring DNA content. For decades, the principal way of conducting ploidy analysis was through flow cytometry. A flow cytometer is a specialized tool for analyzing cells in a solution. This is convenient in laboratory environments, but prohibits measurement reproducibility and the complete detachment of sample preparation from data acquisition and analysis, which seems to have become paramount with the constant decrease in the number of pathologists per capita all over the globe. As more open computer-aided systems emerge in medicine, the demand for overcoming these shortcomings, and opening access to even more (and more flexible) options, has also emerged. Image-based analysis systems can provide an alternative to these types of workloads, placing the abovementioned problems in a different light. Flow cytometry data can be used as a reference for calibrating an image-based system. This article aims to show an approach to constructing an image-based solution for ploidy analysis, take measurements for a basic comparison of the data produced by the two methods, and produce a workflow with the ultimate goal of calibrating the image-based system.

Biological Characteristics of Cervical Precancerous Cell Proliferation

High-grade squamous intraepithelial lesions (HSILs) are regarded as precancerous lesions that can progress to cervical carcinoma; however, it is very difficult to effectively differentiate these precancerous cells from cancerous cells based on morphology alone. Additionally, the difference between precancerous cells and cancerous cells in regard to biological behaviour remains unclear. We previously cultured primary normal uterine cervical keratinocytes from human normal cervical tissue and cervical precancerous cells that were naturally infected with human papillomavirus from small-sized neoplastic cervical tissues. Here, we extended our study to further observe the in vitro proliferative characteristics of cervical precancerous cells at the cellular and molecular levels. In this study, we found that the growth rate of precancerous cells was significantly faster than that of normal cervical cells and slower than that of Caski cells. However, the proliferative capacity of such precancerous cells was similar to that of cancerous cells of the cervix at the molecular level. These results suggest that the surrounding environment of the cells may play an important role in the development of cervical cancer, which provides an important basis for the further study of precancerous and cancerous lesions of the cervix.

DNA ploidy status, S-phase fraction, and p53 are not independent prognostic factors for survival in endometrioid endometrial carcinoma FIGO stage I–III

Objectives

To assess the effects on relative survival of established and new prognostic factors in stage I–III grade 1–3 endometrioid endometrial carcinoma and in the subgroup of stage I grade 1–2.

Methods

This was a population-based, retrospective study including all women (n=1113) in the western Swedish healthcare region diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I–III grade 1–3 endometrioid endometrial carcinoma in 2006–2011. Histology, grade, stage, and age were prospectively reported to the regional clinical and national cancer registers. DNA ploidy and S-phase fraction were analyzed by flow cytometer. S-phase fraction cut-off was set at ≥8%. Tumor biopsies were classified as diploid if there was one G0/G1 peak or the DNA index was 1.0±0.04. Overexpression of p53 as determined by immunohistochemistry was positive if strong nuclear staining was found in >30% of the neoplastic cells.

Results

Based on univariable statistical analyses we found that 5-year relative survival was significantly associated with S-phase fraction, DNA ploidy, p53, stage, grade, and age. Excess mortality for S-phase fraction ≥8%, aneuploidy, and p53 overexpression was 8, 14, and 8 and times higher, respectively. However, in a multivariable regression model, adjusted for stage, grade, and age, S-phase fraction, DNA ploidy, and p53 were not statistically independent prognostic factors (p=0.413, p=0.107, p=0.208, respectively) for 5-year relative survival in stage I–III grade 1–3 endometrioid endometrial carcinoma. In a subgroup analysis of stage I grade 1–2, aneuploidy identified a subgroup with impaired 5-year relative survival.

Conclusion

We can conclude that S-phase fraction, DNA ploidy, and p53 overexpression did not improve identification of high-risk patients by stage, grade, and age in stage I–III endometrioid endometrial carcinoma. In stage I, aneuploidy and grade 2 predicted lower relative survival rates than other variables.

Short-Term Effects of Y-27632, a Rho-Associated Protein Kinase Inhibitor, on Chromatin Supraorganization and DNA Amount in Epithelial Cells of the Rat Cornea and Limbus

PURPOSE

To assess the short-term effects of instilling Y-27632, an inhibitor of Rho/Rho-associated protein kinases, on the chromatin supraorganization and DNA amount of corneal and limbal epithelial cells of healthy rats.

METHODS

Longitudinal sections (7 μm) of enucleated eyes of healthy rats that received, by instillation, balanced salt solution with or without 10 mM of Y-27632 daily for 7 or 15 days, were subjected to the Feulgen reaction. Feulgen-stained nuclei of corneal and limbal epithelial cells were studied by microscopy and video image analysis to establish the nuclear size (area and perimeter), supraorganization of chromatin (texture and degrees of condensation), and the Feulgen-DNA amount.

RESULTS

Instillation of Y-27632 for up to 15 days did not change the size of the nucleus or the chromatin texture of corneal and limbal epithelial cells. Samples treated with Y-27632 for 7 days showed condensed chromatin and a high Feulgen-DNA amount. Both corneal and limbal epithelium showed the presence of near-tetraploid nuclei corresponding to cells in the S and G2 phases of the cell cycle. The degrees of condensation and Feulgen-DNA amount of the nuclei of epithelial cells of the cornea and limbus of eyes from rats receiving Y-27632 for 15 days did not differ from control (no drug).

CONCLUSIONS

Changes in chromatin supraorganization and DNA amount, such as seen in this study, are indicative of cell proliferation and do not seem to be associated with disturbances in gene activity and transcription of DNA.

Risk factors for lymph node metastases in women with endometrial cancer: A population-based, nation-wide register study-On behalf of the Swedish Gynecological Cancer Group

The role of lymphadenectomy in the management of early endometrial cancer remains controversial. In the recent ESMO-ESGO-ESTRO guidelines, lymphadenectomy is recommended for patients with endometrioid adenocarcinoma Grade 3 with deep myometrial invasion, but complete agreement was not achieved. In Sweden, DNA aneuploidy has been included as a high-risk factor. The aim of our study was to evaluate the impact of tumor histology, FIGO grade, DNA ploidy and myometrial invasion (MI) on occurrence of lymph node metastasis (LNM) in patients with endometrial cancer. The study design is a retrospective cohort study based on prospectively recorded register data. Endometrial cancer patients registered in the Swedish Quality Registry for Gynecologic Cancer 2010-2015 with FIGO Stages I-III and verified nodal status were included. Data on DNA ploidy, histology, FIGO grade and MI were included in multivariable log-binomial regression analyses with LNM as dependent variable. 1,165 cases fulfilled the inclusion criteria. The multivariable analyses revealed increased risk of LNM in patients with tumors with MI ≥ 50% (risk ratio [RR] = 4.1; 95% confidence interval [CI] 3.0-5.6), nonendometrioid compared to endometrioid histology (RR 1.8; CI 1.4-2.4) and FIGO Grade 3 compared to Grade 1-2 tumors (RR 1.5; CI 1.1-2.0). No statistically significant association between DNA ploidy status and LNM was detected. This population-based, nation-wide study in women with endometrial cancer confirms a strong association between MI ≥ 50%, nonendometrioid histology and FIGO Grade 3, respectively, and LNM. DNA ploidy should not be included in the preoperative decision making of removing nodes or not.

Morphometric and DNA Image Analysis of Endometrial Hyperplasia and Carcinoma

Endometrial hyperplasia is believed to increase the risk of endometrial carcinoma and represents a spectrum of morphologic and biological alterations of endometrial glands and stroma ranging from an exaggerated physiological state to carcinoma in situ. Considering the overlap between the various entities, it is not surprising that the morphologic assessment of endometrial lesions is particularly challenging. This work aimed to evaluate endometrial lesions according to their nuclear and glandular morphometric parameters, their D score, and their DNA ploidy, which help in making an accurate diagnosis. In this study, 50 endometrial biopsy specimens were stained with hematoxylin and eosin for their histopathologic and morphometric study and Feulgen stain for DNA analysis. The cases were classified into 20 cases of simple hyperplasia, 10 cases of atypical hyperplasia, and 20 cases of endometrial carcinoma. Morphometric analysis of nuclear, glandular, and stromal parameters was performed using the Leica Qwin 500 image analysis system. In the studied cases, a significant difference was found in the mean values of the morphometrical parameters of endometrial lesions, including the nuclear area and the nuclear roundness, and all glandular measurements including their complexity, area, volume percentage of stroma, and D score were significantly different. The DNA index and diploid and aneuploid values could differentiate significantly between endometrial lesions. We conclude that nuclear morphometric evaluation of the hyperplastic and carcinomatous endometrium may be used as an ancillary technique in the diagnosis of atypical changes occurring in precancerous endometrial lesions. In addition, DNA and D score assessment may be a reproducible and accurate predictor of the outcome of endometrial hyperplasia and may add some objective criteria for the correct diagnosis of difficult cases.

Cell proliferation, measured as flow cytometric S-phase fraction, is a strong prognostic indicator in FIGO stage I endometrioid endometrial carcinoma: a population-based study

INTRODUCTION

In early-stage endometrial carcinoma, there is controversy regarding the prognostic value of the flow cytometric variables DNA ploidy (diploid vs. aneuploid) and S-phase fraction. In Sweden, the former is included in national guidelines despite poor scientific support and the latter is not used clinically. This study investigates the prognostic properties of these variables, together with classical histopathological variables, in multivariate analysis in a stringently stratified material.

MATERIAL AND METHODS

Consecutive, population-based patient material restricted to International Federation of Gynecology and Obstetrics (FIGO) 2009 stage I endometrioid endometrial carcinoma (n = 1140) was retrospectively collected from routinely reported data from medical records. Data on age, FIGO stage, degree of differentiation, S-phase fraction, DNA ploidy status, and adjuvant treatment were included in the study. Cumulative incidence curves with other causes of death as a competing risk were used for univariable analysis for the primary endpoint endometrial cancer death. Cox proportional hazards regression analysis was used for multivariate modeling of all endpoints, and for univariable analysis for the secondary endpoints overall survival and time to progression.

RESULTS

An S-phase fraction value of >5.5% was associated with worse outcome (for endometrial cancer death: hazard ratio 2.25; 95% CI 1.38-3.67; p = 0.001, adjusted) and DNA ploidy status was not, for all endpoints tested.

CONCLUSIONS

In FIGO stage I endometrioid endometrial carcinoma, DNA ploidy status had no prognostic value, whereas the S-phase fraction may be used to identify those with a higher risk of adverse clinical outcome.

BRCA1 mutation site may be linked with nuclear DNA ploidy in BRCA1-mutated ovarian carcinomas

AIMS

BRCA1 has a role in maintaining normal nuclear DNA content during cell division and its inactivation may result in DNA aneuploidy and cancer progression. BRCA1-linked breast cancers are more aneuploid and have a worse prognosis, but this has not been elucidated in ovarian cancers. This study explores the potential difference in ploidy status between BRCA1-mutated and sporadic ovarian carcinomas. It also explores the potential association between BRCA1 mutation site and DNA ploidy status.

METHODS

This study compared DNA ploidy status of tumor blocks from 23 BRCA1-mutated ovarian carcinomas with that of 23 sporadic ovarian carcinomas matched for histologic subtype, patient age, stage and grade. DNA content of the nuclei was measured by Feulgen-Schiff staining followed by image cytometry and compared.

RESULTS

BRCA1-linked tumors with a stop codon closer to the N-terminal (between 1 and 500 aa; 6/6, 100%) had a significantly higher frequency of nondiploidy compared with those with stop codon above 500 aa (7/12, 58%) (P = 0.033). A diploid peak was detected in 28% of BRCA1-mutated ovarian cancers and in 33% of sporadic ovarian cancers.

CONCLUSIONS

The present study concluded that ovarian tumors with mutations closer to the N-terminal of BRCA1 may have a higher risk of DNA aneuploidy. There is no significant difference between BRCA1-mutated and sporadic ovarian carcinomas with respect to the DNA content.

Clinical value of DNA content assessment in endometrial cancer

Endometrial carcinoma (EC) is the most common gynecologic cancer in industrialized countries. Traditional prognostic markers include FIGO stage, histologic subtype, and histologic grade. DNA ploidy was introduced as a prognostic marker 30 years ago, and the majority of published literature demonstrates significant associations between tumor aneuploidy and poorer prognosis in EC. However, ploidy analysis is not routinely implemented in the clinic. We reviewed the literature on clinical value of ploidy measured by DNA content as a prognostic marker, and its potential role as a predictive marker in EC.  PubMed was searched for papers evaluating the prognostic or predictive role of ploidy in EC. Search criteria were "DNA ploidy prognosis/predictive value endometrial cancer/carcinoma". Only articles written in English, published year 2000 or later were included.  The majority of the studies demonstrated highly significant correlation between DNA index (DI) and survival, in univariate analysis including stages I-IV, and in subgroup analysis of stage I and stage I-II EC. Several studies also showed significant association between DI and survival in multivariate analysis. Few studies have evaluated DI as a prognostic marker in a prospective setting. No studies evaluating DI as a predictive marker in EC were identified. In other cancer types, ploidy has been linked to prediction of response to hormonal therapy and chemotherapy.  Ploidy assessment in EC by DI is a strong prognostic marker. Still, its clinical applicability needs validation in a routine diagnostic, prospective setting with sufficient number of patients, characterized by state of the art histopathological evaluation and surgical staging.

DNA ploidy measured on archived pretreatment biopsy material may correlate with prostate-specific antigen recurrence after prostate brachytherapy

PURPOSE

To explore whether DNA ploidy of prostate cancer cells determined from archived transrectal ultrasound-guided biopsy specimens correlates with disease-free survival.

METHODS AND MATERIALS

Forty-seven failures and 47 controls were selected from 1006 consecutive low- and intermediate-risk patients treated with prostate (125)I brachytherapy (July 1998-October 2003). Median follow-up was 7.5 years. Ten-year actuarial disease-free survival was 94.1%. Controls were matched using age, initial prostate-specific antigen level, clinical stage, Gleason score, use of hormone therapy, and follow-up (all P nonsignificant). Seventy-eight specimens were successfully processed; 27 control and 20 failure specimens contained more than 100 tumor cells were used for the final analysis. The Feulgen-Thionin stained cytology samples from archived paraffin blocks were used to determine the DNA ploidy of each tumor by measuring integrated optical densities.

RESULTS

The samples were divided into diploid and aneuploid tumors. Aneuploid tumors were found in 16 of 20 of the failures (80%) and 8 of 27 controls (30%). Diploid DNA patients had a significantly lower rate of disease recurrence (P=.0086) (hazard ratio [HR] 0.256). On multivariable analysis, patients with aneuploid tumors had a higher prostate-specific antigen failure rate (HR 5.13). Additionally, those with "excellent" dosimetry (V100 >90%; D90 >144 Gy) had a significantly lower recurrence rate (HR 0.25). All patients with aneuploid tumors and dosimetry classified as "nonexcellent" (V100 <90%; D90 <144 Gy) (5 of 5) had disease recurrence, compared with 40% of patients with aneuploid tumors and "excellent" dosimetry (8 of 15). In contrast, dosimetry did not affect the outcome for diploid patients.

CONCLUSIONS

Using core biopsy material from archived paraffin blocks, DNA ploidy correctly classified the majority of failures and nonfailures in this study. The results suggest that DNA ploidy can be used as a useful marker for aggressiveness of localized prostate cancer. A larger study will be necessary to further confirm our hypothesis.

Prognostic importance of DNA ploidy and DNA index in stage I and II endometrioid adenocarcinoma of the endometrium

BACKGROUND

We evaluated the prognostic importance of DNA ploidy in stage I and II endometrioid adenocarcinoma (EAC) of the endometrium with a focus on DNA index.

PATIENTS AND METHODS

High-resolution DNA ploidy analysis was carried out in tumor material from 937 consecutive patients with International Federation of Gynecology and Obstetrics (FIGO) stage I and II EAC of the endometrium.

RESULTS

Patients with diploid (N = 728), aneuploid tumor with DNA index ≤ 1.20 (N = 118), aneuploid tumors with DNA index >1.20 (N = 39) and tetraploid tumor (N = 52) had 5-year recurrence rates 8%, 14%, 20% and 12%, respectively. Patients with aneuploid tumor with DNA index >1.20 had a poorer 5-year progression-free survival (67%) and overall survival (72%) compared with the patients with aneuploid tumor with DNA index ≤ 1.20 (81% and 89%, respectively). Aneuploid tumors with DNA index ≤ 1.20 relapsed mainly in the vagina and pelvis, whereas aneuploid tumors with DNA index >1.20 relapsed predominantly outside pelvis.

CONCLUSIONS

The recurrence risk for the patients with aneuploid tumor is higher than the patients with diploid tumor in EAC of the endometrium. Based on DNA index with cut-off 1.20, aneuploid tumors can be separated into two subgroups with different recurrence pattern and survival.

Comparison of nuclear texture analysis and image cytometric DNA analysis for the assessment of dysplasia in Barrett's oesophagus

Background:

Dysplasia is a marker of cancer risk in Barrett's oesophagus (BO), but this risk is variable and diagnosis is subject to inter-observer variability. Cancer risk in BO is increased when chromosomal instability is present. Nucleotyping (NT) is a new method that uses high-resolution digital images of nuclei to assess chromatin organisation both quantitatively and qualitatively. We aimed to evaluate NT as a marker of dysplasia in BO and compare with image cytometric DNA analysis (ICM).

Methods:

In all, 120 patients with BO were studied. The non-dysplastic group (n=60) had specialised intestinal metaplasia only on two consecutive endoscopies after 51 months median follow-up (IQR=25–120 months). The dysplastic group (n=60) had high-grade dysplasia or carcinoma in situ. The two groups were then randomly assigned to a training set and a blinded test set in a 1 : 1 ratio. Image cytometric DNA analysis and NT was then carried out on Feulgen-stained nuclear monolayers.

Results:

The best-fit model for NT gave a correct classification rate (CCR) for the training set of 83%. The test set was then analysed using the same textural features and yielded a CCR of 78%. Image cytometric DNA analysis alone yielded a CCR of 73%. The combination of ICM and NT yielded a CCR of 84%.

Conclusion:

Nucleotyping differentiates dysplastic and non-dysplastic BO, with a greater sensitivity than ICM. A combination score based on both techniques performed better than either test in isolation. These data demonstrate that NT/ICM on nuclear monolayers is a very promising single platform test of genomic instability, which may aid pathologists in the diagnosis of dysplasia and has potential as a biomarker in BO.

Image cytometry accurately detects DNA ploidy abnormalities and predicts late relapse to high-grade dysplasia and adenocarcinoma in Barrett's oesophagus following photodynamic therapy

Background and aims:

DNA ploidy abnormalities (aneuploidy/tetraploidy) measured by flow cytometry (FC) are strong predictors of future cancer development in untreated Barrett's oesophagus, independent of histology grade. Image cytometric DNA analysis (ICDA) is an optical technique allowing visualisation of abnormal nuclei that may be undertaken on archival tissue. Our aim was to determine the accuracy of ICDA vs FC, and evaluate DNA ploidy as a prognostic biomarker after histologically successful treatment with photodynamic therapy (PDT).

Methods:

Nuclei were extracted from 40 μm sections of paraffin-embedded biopsies and processed for ICDA at UCL and FC at UW using standardised protocols. Subsequently, DNA ploidy was evaluated by ICDA on a cohort of 30 patients clear of dysplasia 1 year after aminolaevulinic acid PDT for high-grade dysplasia (HGD). The results were correlated with long-term outcome.

Results:

In the comparative study, 93% (41 out of 44) of cases were classified identically. Errors occurred in the near-diploid region by ICDA and the tetraploid region by FC. In the cohort study, there were 13 cases of late relapse (7 cancer, 6 HGD) and 17 patients who remained free of dysplasia after a mean follow-up of 44 months. Aneuploidy post-PDT was highly predictive for recurrent HGD or cancer with a hazard ratio of 8.2 (1.8–37.8) (log-rank P=0.001).

Conclusions:

ICDA is accurate for the detection of DNA ploidy abnormalities when compared with FC. After histologically successful PDT, patients with residual aneuploidy are significantly more likely to develop HGD or cancer than those who become diploid. DNA ploidy by ICDA is a valuable prognostic biomarker after ablative therapy.

Prognostic factors in surgical stage I endometrial carcinoma

The prognostic impact of DNA ploidy, MIB-1 and p53 was evaluated in relation to clinical and histopathological features in surgical stage I endometrial carcinoma (n = 284) and in the histopathological endometrioid subgroup (n = 257). Tumour material from 284 consecutive patients was analysed regarding image cytometric DNA ploidy and the immunohistochemical MIB-1 and p53 expression. Twenty-four tumours relapsed. In univariate analysis, histopathological subgroup (endometrioid vs. non-endometrioid), grade, DNA ploidy and p53 were highly significant prognostic factors (p < or = 0.001). MIB-1 was also significant (p = 0.039). In the endometrioid subgroup only DNA ploidy and p53 were significant (p < 0.001). In multivariate analysis of the entire material, ploidy and histopathological subgroup retained their significance (p = 0.001, p = 0.004), whereas only ploidy was significant in the endometrioid subgroup (p = 0.001). DNA ploidy was the strongest predictor of relapse-free survival and the only independent prognostic factor in the endometrioid subgroup.

Ovarian carcinoma cells in effusions show increased S-phase fraction compared to corresponding primary tumors

The objective of this study was to analyze large-scale genomic patterns during disease progression from primary tumor to effusion in ovarian carcinoma, and to study the association between DNA ploidy parameters in effusions, proliferation/survival markers, and clinicopathologic characteristics. DNA ploidy status, DNA index (DI), and S-phase fraction (SPF) were compared in 22 matched primary carcinomas (all prechemotherapy specimens) and effusions (14 prechemotherapy and 8 postchemotherapy specimens) using image analysis. The association between these parameters and previously studied cell survival/proliferation biomarkers, previous administration of chemotherapy, chemotherapy response and survival was analyzed in a larger series of 54 effusions. The majority of specimens were aneuploid irrespective of anatomic site, with no significant differences in DI. SPF was significantly higher in effusions compared to matched primary tumors (P = 0.007 for all 22 pairs, P = 0.011 for 14 matched prechemotherapy specimens). Higher SPF was related to higher Ki-67 score (P = 0.045), and both SPF and DI were directly associated with higher level of Survivin (P < 0.001 for both). DI and SPF in effusions showed no association with histological grade, FIGO stage, residual disease volume, previous chemotherapy, response to chemotherapy at primary disease, recurrence or survival. Ovarian carcinoma cells in effusions have increased proliferation compared to corresponding primary tumors, as evidence of disease progression. DNA ploidy parameters in cancer cells in effusions are unaltered by chemotherapy and appear to be unrelated to chemotherapy response and to survival, suggesting that large-scale genomic patterns at this anatomic site are not useful in segregating patients into prognostic groups.

DNA ploidy analysis in salivary gland tumours by image cytometry

AIM

To determine whether DNA ploidy by image cytometry is a good diagnostic tool to distinguish benign and malignant salivary gland tumours.

METHODS

A total of 62 salivary gland tumours were studied. Cases were histologically diagnosed [haematoxylin and eosin (H&E)]. According to the World Health Organization (WHO) classification, there were 14 mucoepidermoid carcinomas (MEC), 11 adenoid cystic carcinomas (ACC), 10 pleomorphic adenomas (PA), 10 carcinoma ex PA (CEPA), 9 acinic cell carcinomas (ACCa), 3 polymorphous low-grade adenocarcinomas (PLGA), 2 papillary cystadenocarcinomas (PC), 1 myoepithelial carcinoma (MC), 1 undifferentiated carcinoma (UC) and 1 mucinous adenocarcinoma (MA). Paraffin sections (40 microm) were micro-dissected to isolate tumour areas; cell nuclei were extracted and Feulgen-stained cytospin monolayers were analysed using a DNA image cytometry system. For each case, DNA index (DI) was calculated relative to internal controls (lymphocytes; DI=1.0). Cases were categorized as diploid or aneuploid and the proportion of cells over 5c was also calculated.

RESULTS

Fifty-three of 62 salivary gland tumours were uniformly diploid. Only nine cases were aneuploid: five CEPA, one low-grade MEC, one PC, one UC and one MA.

CONCLUSIONS

The vast majority of salivary gland tumours were diploid. High-grade malignancies may be aneuploid, and ploidy may be useful to identify malignant change in atypical PA. Further, larger studies are needed to confirm our results and to further evaluate the usefulness of the technique in high-grade lesions.

Image cytometry DNA ploidy correlates with histological subtypes in endometrial carcinomas

Image cytometric DNA ploidy analysis of endometrial carcinomas was performed to determine whether ploidy status and ploidy-related parameters like DNA index, percentage of cells exceeding 5c and 9c, correlate with histologic subtype. This is a prospective study of 391 patients with stage I endometrial carcinoma which included 331 (85%) endometrioid adenocarcinoma, 22 (6%) serous adenocarcinoma, 7 (2%) clear cell adenocarcinoma, 2 (0.5%) small cell carcinoma, 1 (0.3%) undifferentiated carcinoma, and 28 (7%) unclassifiable adenocarcinoma. Twenty-five percent of endometrioid adenocarcinomas were non-diploid. In contrast, all clear cell adenocarcinomas and 21/22 (95%) of serous adenocarcinomas were non-diploid. Hyperdiploidy (25 cases) was found only in endometrioid adenocarcinomas. Mean DNA index of the stemline in serous adenocarcinoma (1.72) and clear cell adenocarcinoma (1.81) was higher than in endometrioid adenocarcinoma (1.1). The difference in ploidy-related parameters between endometrioid adenocarcinoma and serous adenocarcinoma was highly significant (P<0.001). In addition, Grade 3 endometrioid adenocarcinoma showed significant difference in all ploidy-related parameters compared with grade 1 and grade 2 tumors (P<0.001). Our results show that DNA ploidy-related parameters may be valuable in subtyping histologically difficult cases of endometrial carcinomas.

Prognostic factors in ovarian carcinoma stage III patients. Can biomarkers improve the prediction of short- and long-term survivors?

The aim of the study was to determine if biomarker expression could help discriminate between short-term and long-term survivors in women with advanced ovarian cancer. Fifty-one patients with stage III ovarian cancer were selected for the study, which included 28 short-term survivors (death from ovarian cancer within 18 months) and 23 long-term survivors (alive for more than 5 years). There was no difference between the two groups with respect to FIGO substage, age, World Health Organization score, and first-line platinum therapy. Classic clinical pathologic parameters were examined together with p53, Bcl-2, Ki-67, PDGFRalpha, P-glycoprotein, BRCA1, and DNA ploidy. Immunohistochemistry was used for scoring biomarker expression and image cytometry for DNA ploidy. All patients had primary debulking surgery followed by first-line platinum therapy. On multivariate analysis, the presence of ascites, debulking surgery and repeat laparotomy, clear-cell histology, elevated CA125, and high Ki-67 score were all found to be of prognostic importance. The long-term survivors were characterized by primary optimal cytoreduction surgery (<1 cm residual disease), attempt at maximal tumor debulking by experienced gynecological oncologic surgeons, and the absence of ascites. Normal CA125 level before platinum therapy and negative Ki-67 expression also predicted a more favorable prognosis.

Large-scale genomic instability predicts long-term outcome for women with invasive stage I ovarian cancer

BACKGROUND

The objective was to evaluate the value of DNA ploidy using high-resolution image cytometry in predicting long-term survival of patients with early ovarian cancer.

PATIENTS AND METHODS

A retrospective analysis of 284 cases with FIGO stage I ovarian carcinoma treated during the period 1982-1989 was performed. Clinical follow-up information was available for all patients.

RESULTS

Patients with diploid and tetraploid tumors had a 10-year relapse-free survival of 95% and 89%, respectively, compared with 70% and 29% for polyploid and aneuploid tumors, respectively. DNA ploidy analysis was the strongest predictor of survival in multivariate analysis (diploid/tetraploid versus polyploid/aneuploid; relative hazard 9.0) followed by histological grade, including clear cell tumors in the group of poorly differentiated tumors (grade 1-2 versus grade 3 or clear cell; relative hazard 2.7), and FIGO stage (Ib/Ic versus Ia; relative hazard 2.0). In a stratified Kaplan-Meier analysis, patients with grade 1-2, diploid or tetraploid tumors had a 10-year relapse-free survival of 95%, forming a low-risk group. Patients with grade 3 or clear cell, diploid or tetraploid tumors had 10-year relapse-free survival of 86%, forming an intermediate-risk group, while all patients with aneuploid/polyploid tumors formed a high-risk group, with 10-year relapse-free survival of 34%.

CONCLUSIONS

This study points to the importance of including DNA ploidy analysis by image cytometry when selecting patients with early ovarian cancer for adjuvant treatment after surgery.

Nuclear DNA content, proliferative activity, and p53 expression related to clinical and histopathologic features in endometrial carcinoma

The purpose of this study was to evaluate the prognostic impact of image cytometry DNA ploidy, MIB-1, and p53 in relation to clinicopathologic variables in 376 consecutive patients with endometrial carcinoma stages I-IV. Following primary treatment 358 patients were considered tumor-free. Relapses and tumor-specific deaths of these patients were noted. Image cytometry DNA ploidy (n = 340) and expression of MIB-1 (n = 318) and p53 (n = 323) were studied. In univariate analysis, stage (P < 0.001), histopathologic subtype (P < 0.001), degree of differentiation (P < 0.001), HRT (P = 0.034), DNA ploidy (P < 0.001), and p53 (P < 0.001) were significant predictors of relapse. Patient age showed that the estimated mean risk of relapse increases with nearly 64% per decade in life (P 0.003), and the MIB-1 expression with 21% per 10-unit increment (P 0.004). In multivariate analysis, degree of differentiation, MIB-1, and p53 lost their prognostic capability. However, after stage and histopathologic subtype, image cytometry DNA ploidy was the strongest predictor of outcome and was of value in predicting the risk for relapse. The combination of DNA ploidy, MIB-1, and p53 expression was an even stronger predictor of relapse-free survival than the individual prognostic factors.

Prognostic significance of DNA content and S-phase fraction in epithelial ovarian carcinomas analyzed by image cytometry

The objective of this study was to evaluate the prognostic significance of DNA ploidy and S-phase fraction (SPF) in epithelial ovarian carcinomas analyzed by image cytometry. Frozen tissue of 103 epithelial ovarian carcinomas was analyzed for DNA ploidy and SPF with a Cell Analysis System Image Analyser (CAS 200, Becton-Dickinson) and correlations with clinical and histomorphologic factors and time to progression and overall survival were evaluated by univariate and multivariable analysis. Fifty-four percent of the ovarian carcinomas were found to be diploid, 38% aneuploid, and 8% tetraploid. The S-phase fraction was low (<5%) in 27%, intermediate (5-14.5%) in 47%, and high (>/=14.5%) in 26% of the patients. By univariate analysis overall survival and time to progression were significantly correlated with the S-phase fraction (P = 0.003 and P = 0.003), but not with DNA ploidy (P = 0. 31 and P = 0.51). A DNA index > 1.4 was correlated with poor outcome but the result did not achieve formal statistical significance (P = 0.08 and P = 0.12). A high SPF was a strong predictor of early recurrence, while a low SPF identified patients with a favorable long-term outcome. Other significant predictors of survival were FIGO stage, grade of differentiation, presence of distant metastasis, residual tumor, lymph node metastasis, and patient age. In multivariable statistical analysis only FIGO stage, histologic grade, and residual tumor after surgery were independent predictors of overall survival and time to progression.

Heterogeneity of DNA ploidy pattern in carcinoma of the gallbladder: primary and metastatic sites

There are few detailed reports on the heterogeneity of the nuclear DNA ploidy pattern in carcinoma of the gallbladder. We studied twelve autopsied cases who died of extended gallbladder carcinoma. Multiple samples were taken from the primary site (Pri), from direct invasion of the liver (Hinf), from hematogenous metastasis to the liver (H), from lymphatic metastasis (LN) and from peritoneal dissemination (P). The DNA ploidy pattern was investigated by image cytometry. Heterogeneity of the DNA ploidy pattern in Pri, Hinf, H, LN and P was found in 7/11, 2/10, 5/10, 2/6 and 3/6 cases, respectively. Aneuploidy was more frequently found in Hinf than at the Pri. The DNA index of Hinf was significantly higher than that of Pri. Several stemlines, with different quantities of DNA, were found in Pri. Most of these stemlines were also observed in other sites. These facts may suggest that polyclonal cancer cells rather than one cancer cell or monoclonal cancer cells of a Pri metastasize or infiltrate, and that various polyclonal cancer cells proliferate to different degrees under different circumstances.

Microsatellite instability in cervical and endometrial carcinomas

Microsatellite instability has been found preferentially in tumours associated with the hereditary non-polyposis-colorectal-cancer (HNPCC) syndrome. This phenotype, manifested as new alleles at microsatellite loci, and often the result of a defective mismatch-repair gene, is seen as allelic mobility shifts during electrophoretic runs. We examined possible alterations at 8 dinucleotide loci mapping to 6 different chromosomes in endometrial cancers (n = 20) and cervical cancers (n = 82). Overall instability was found in 30% of the endometrial cancers and in 6% of the cervical cancers, including 3 (15%) and 2 (2%) tumours, respectively, unstable at more than one locus. In contrast to the endometrial cancer sub-group, the affected cervical cancers were characterized by one or two new alleles at one or few loci. By DNA ploidy measurements 5 diploid endometrial cancers were microsatellite-unstable vs. one diploid of 6 unaltered cases (p = 0.015; Fisher's exact test). Our data confirm that a sub-set of diploid sporadic endometrial cancers are characterized by a mutator phenotype similar to that found in colorectal cancer. In contrast, among cervical cancers, not characterized by the HNPCC-tumour spectrum, this mutator phenotype is seen infrequently, and positive cases appear to display only minor alterations.

DNA image cytometry on sections as compared with image cytometry on smears and flow cytometry in melanoma

DNA measurements of 130 melanomas were carried out by flow cytometry (FCM) and image cytometry (ICM). ICM was applied to cytological preparations of fresh material (cICM) and to sections of formalin-fixed paraffin embedded tissue (sICM). The DNA ploidy, the DNA index of G0/G1 peaks (DI), and the proliferation index (PI) were used to compare all the methods. The following parameters reflecting malignancy were calculated only from ICM histograms: the 5c exceeding rate (5cER) and the malignancy grade (MG). In cases found to be DNA aneuploid by FCM, the PI values (FCM versus cICM) and the DIs (between all methods) showed a high correlation, and the concordance in relation to the DNA ploidy status was 96% (FCM versus cICM) and 94% (FCM versus sICM). However, we ascertained essential differences between FCM and ICM in melanomas classified as DNA diploid by FCM. The concordance in DNA ploidy was only 66% (FCM versus cICM) and 64% (FCM versus sICM). In contrast, cICM and sICM yielded similar results in most cases. With the exception of the near diploid range, ICM is superior to FCM in detecting DNA aneuploidy. In particular, DNA tetraploid stem lines can easily be overlooked by FCM. Therefore, DNA measurements of tumours judged to be DNA diploid by FCM must be verified by ICM. ICM on sections proved to be applicable and yielded reliable results provided that a suitable thickness was used, and the measuring of sectioned and overlapping nuclei was largely avoided by careful focusing in either direction.

An evaluation of prognostic factors in advanced ovarian cancer

A summary is presented of currently available prognostic factors in advanced ovarian cancer of the common epithelial types. The emphasis is on the most promising clinical, classical pathological, biochemical, immunohistochemical, molecular biological and quantitative pathological factors.

Cytology, flow cytometry, image analysis, and interphase cytogenetics by fluorescence in situ hybridization in the diagnosis of transitional cell carcinoma in bladder washes: a comparative study

The diagnosis of transitional cell carcinoma (TCC) in bladder washes is a diagnostic challenge to cytology. This study assessed the role of flow cytometry (FCM), image analysis (IA), and interphase cytogenetics by fluorescence in situ hybridization (FISH) as adjuncts in the cytodiagnosis of TCC in bladder washes. Forty separate samples of bladder washes were prospectively evaluated by conventional cytology (CY), FCM, IA, and FISH, and the results were compared with the subsequent surgical biopsy specimens which revealed 26 TCC (3 GR I, 6 GR II, 17 GR III) and 14 benign lesions. Using histology as the "gold standard" and following the previously published criteria for detection of TCC by CY, FCM, IA, and FISH, the concordance rates between histology and CY, FCM, IA, and FISH were 75, 74, 89, and 83%, respectively. CY, FCM, IA, FISH, and histology were concordant in 54% of the cases. The sensitivity of CY, FCM, IA, and FISH were 61, 72, 91, and 73%, respectively, while the specificity were 100, 80, 83, and 100%, respectively. The combined sensitivity of all the parameters was 96%. Interestingly, the false positive cases by FCM and IA showed cystitis. We conclude that IA has the highest sensitivity in detecting TCC in bladder washes followed by FISH, FCM, and CY, while CY and FISH have the highest specificity. This study indicates that FCM, IA, and FISH are useful adjuncts to cytology in the diagnosis of TCC in bladder washes. The finding of DNA-aneuploidy in cystitis warrants further investigation.

Cytophotometric and flow cytometric DNA content of isolated glands in gastric neoplasia

The gland isolation method was applied to various gastric lesions to measure DNA content by cytophotometry and flow cytometry for the first time. By incubating and agitating fresh specimens from surgically resected stomachs in calcium-magnesium free Hanks's balanced salt solution (CMFH) containing EDTA, many neoplastic glandular epithelial cells were successfully isolated from the stroma, and their characteristic three dimensional features were seen morphologically. The DNA content of pure nuclear suspensions of isolated glands was obtained by cytophotometry and flow cytometry staining with 4',6-diamino-2-phenylindole dihydrochloride (DAPI) and propidium iodide, respectively. Compared with histological grading, the frequency of the DNA aneuploidy of cancer with moderate or poor differentiation by cytophotometry (75%) was significantly higher than that of well differentiated cancer (25%), but the histological typing of gastric cancer DNA frequency were not correlated. This method allowed us to detect small aneuploid peaks by flow cytometry, which were previously masked by contaminating interstitial cells. The frequency of DNA aneuploidy detected by flow cytometry (87.5%) was higher than detected by cytophotometry (58.3%). The results of these studies shows the feasibility of this technique for analysing the DNA content of various lesions of the stomach.

Prognostic significance of DNA cytometry in comparison with histologic measurements in malignant melanomas

In the present study we evaluated the prognostic impact of both DNA cytometry and quantitative histology in patients with malignant melanoma (MM). In contrast to previous investigations on sections, rapid image analysis (IA) of imprint specimens was performed to measure DNA cytometric features; 34 cases of stage I MM with low (< 1.5 mm, n = 20) and higher tumor thickness (TTH) (> 1.5 mm, n = 14) were analyzed. We found significant correlations between cytometric features and TTH, which is accepted as the most important prognostic criterion in MM. Higher TTH was closely correlated with the rate of markedly aneuploid nuclei, which is indicated by the 5c exceeding rate (5cER; r, 0.89; p < 0.001). The gain of chromatin in thicker tumors was accompanied by higher mean nuclear area (MAREA; r, 0.60; p < 0.001) and mean DNA content (MDNA; r, 0.58; p < 0.001). Additional evidence for prognostic significance of cytometry was obtained by preliminary survival analysis of 16 cases (four patients died within 2 1/2 years and 12 patients survived for at least 4 1/2 years). Applying multivariate stepwise discriminant analysis, a combination of TTH, level of invasion (LEV), 2c deviation index (2cDI), and modified standard deviation of the DNA values (SDNAM) proved to be most effective. One hundred percent of the cases were correctly classified as survivors or nonsurvivors. TTH and the 5cER were found to be the best univariate criteria for prognosis. In the U test according to Mann and Whitney, a significant discrimination of survivors and nonsurvivors was possible using either TTH or the 5cER, respectively (p < 0.02). Thus, we would like to conclude that IA of imprint specimens can be recommended as a rapid and simple additional method for grading.

Quantitative DNA measurement by flow cytometry and image analysis of human nonseminomatous germ cell testicular tumors

Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30-40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M + S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only.

Flow cytometric DNA ploidy and S-phase heterogeneity in advanced ovarian carcinoma

BACKGROUND

The prognostic significance of flow cytometric DNA ploidy and S-phase fraction (SPF) in ovarian cancer has been controversial. In the current study, the authors analyzed tumor heterogeneity in respect to DNA index DI and SPF.

METHODS

Flow cytometric variation in DI and SPF among representative fresh tumor material from the primary tumor, metastasis, and malignant effusions from the same patient was analyzed.

RESULTS

One hundred thirty-two samples from 47 patients were analyzed, and 119 samples from 42 patients were evaluable. Stable DI between different samples was found in 34 patients, whereas heterogeneity was found in 8 patients (19%). The metastases showed stable DNA content. The malignant effusion samples often lacked tumor cells. The representative ones were often DNA diploid. In 21% of the aneuploid samples, the SPF could not be analyzed. In 38% of the aneuploid samples, the stem line constituted less than 15% of measured nuclei. In these samples, a negative correlation between SPF and percentage of aneuploid cells was found, making SPF unreliable. Correct SPF measurement was thus possible in only 41% of the aneuploid samples, and in these tumors, SPF values varied considerably among different samples from the same patient, illustrated by a median SPF difference of 11% (range, 0-28%).

CONCLUSIONS

Tumor DI heterogeneity existed in 19% of tumors. SPF depended on the amount of aneuploid cells in case of small stem lines and varied considerably, making its use as a prognostic factor doubtful. To ensure that all tumor stem lines are represented, at least two biopsy specimens from any solid tumor should be analyzed.

Evaluation of deoxyribonucleic acid ploidy and S-phase fraction as prognostic parameters in advanced epithelial ovarian carcinoma: a prospective study

OBJECTIVE

Our goal was to study the prognostic value of deoxyribonucleic acid ploidy and S-phase fraction in advanced ovarian carcinoma.

STUDY DESIGN

Prognostic factors for corrected survival were evaluated in a prospective study including 169 patients with stage III and IV ovarian cancer treated between 1985 and 1990.

RESULTS

A total of 79% of the tumors were deoxyribonucleic acid aneuploid. Deoxyribonucleic acid aneuploidy was associated with grade of differentiation. S-phase fraction could be calculated in all deoxyribonucleic acid euploid tumors and 76% of the deoxyribonucleic acid aneuploid tumors. By multivariate analysis deoxyribonucleic acid ploidy, histologic type and grade, age, International Federation of Gynecology and Obstetrics stage, and amount of residual tumor were independent prognostic variables for corrected survival. On the basis of Cox regression a relative risk for the individual patient could be calculated.

CONCLUSION

Deoxyribonucleic acid ploidy gives additive prognostic information and is a useful parameter for dividing patients with advanced ovarian cancer into risk groups for treatment decisions.