Combined flow cytometry determination of S-phase fraction and DNA ploidy is an independent prognostic factor in node-negative invasive breast carcinoma: analysis of a series of 271 patients with stage I and II breast cancer

Clinical Implications of Chromosomal Instability (CIN) and Kinetochore Abnormalities in Breast Cancers

Genetic instability is a defining property of cancer cells and is the basis of various lesions including point mutations, copy number alterations and translocations. Chromosomal instability (CIN) is part of the genetic instability of cancer and consists of copy number alterations in whole or parts of cancer cell chromosomes. CIN is observed in differing degrees in most cancers. In breast cancer, CIN is commonly part of the genomic landscape of the disease and has a higher incidence in aggressive sub-types. Tumor suppressors that are commonly mutated or disabled in cancer, such as p53 and pRB, play roles in protection against CIN, and as a result, their dysfunction contributes to the establishment or tolerance of CIN. Several structural and regulatory proteins of the centromeres and kinetochore, the complex structure that is responsible for the correct distribution of genetic material in the daughter cells during mitosis, are direct or, mostly, indirect transcription targets of p53 and pRB. Thus, despite the absence of structural defects in genes encoding for centromere and kinetochore components, dysfunction of these tumor suppressors may have profound implications for the correct function of the mitotic apparatus contributing to CIN. CIN and its prognostic and therapeutic implications in breast cancer are discussed in this article.

Metastatic and triple-negative breast cancer: challenges and treatment options

The major current conventional types of metastatic breast cancer (MBC) treatments include surgery, radiation, hormonal therapy, chemotherapy, or immunotherapy. Introducing biological drugs, targeted treatment and gene therapy can potentially reduce the mortality and improve the quality of life in patients with MBC. However, combination of several types of treatment is usually recommended. Triple negative breast cancer (TNBC) accounts for 10-20% of all cases of breast carcinoma and is characterized by the low expression of progesterone receptor (PR), estrogen receptor (ER), and human epidermal growth factor receptor 2 (HER2). Consequently, convenient treatments used for MBC that target these receptors are not effective for TNBC which therefore requires special treatment approaches. This review discusses the occurrence of MBC, the prognosis and predictive biomarkers of MBC, and focuses on the novel advanced tactics for treatment of MBC and TNBC. Nanotechnology-based combinatorial approach for the suppression of EGFR by siRNA and gifitinib is described.

DNA aneuploidy and breast cancer: a meta-analysis of 141,163 cases

BACKGROUND & AIMS

DNA ploidy, a DNA flow cytometry parameter, reflects tumor cell cycle. In breast cancer (BC), ploidy status characterizes genotypic stability and potential metastatic capacity. It is suggested that aneuploidy is an independent prognosticator for BC patients and could aid for individualized medicine. There are extensive studies concerning the prognostic significance of DNA aneuploidy, however, its clinical utility remains controversial. Herein we conducted a meta-analysis to determine the correlation between DNA ploidy status and BC characteristics and survival.

METHODS

The electronic databases PubMed, EMBASE, and Web of Science were searched for relevant studies. The major investigated parameters were the BC aneuploidy rates in relation to tumor stage, size, lymph node metastasis, grading, estrogen receptor (ER) status, disease-free survival (DFS), and overall survival (OS). Hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) for DFS and OS were extracted from each study before meta-analyzed. Risk ratios (RRs) were computed using the fixed-effect or random-effects model according to data heterogeneity, and the Mantel-Haenszel or the inverse-variance method was adopted where appropriate to obtain pooled estimates using RevMan 5.3. The Egger's test was conducted with Stata 11.

RESULTS

Pooled analyses of data from 29 studies involving a total of 141,163 cases showed that BC patients with more advanced tumors (stage I vs. stages II-IV, RR=0.84; 95% CI, 0.74 to 0.96; P=0.01), larger tumors (≤2 cm vs. >2 cm: RR=0.82; 95% CI, 0.77 to 0.87; P<0.00001), lymph node metastasis (pN0 vs. pN1-3: RR=0.85; 95% CI, 0.83 to 0.87, P<0.00001), poorer tumor proliferation (G2 vs. G1: RR=1.58; 95% CI, 1.40 to 1.79; P<0.00001; G3 vs. G1: RR=2.17; 95% CI, 1.77 to 2.67; P<0.00001; G3 vs. G2: RR=1.41; 95% CI, 1.25 to 1.60; P<0.00001), and ER- status (ER-vs. ER+: RR=1.32; 95% CI, 1.22 to 1.43; P<0.00001) were significantly more frequently aneuploid. BC patients with diploid tumors had better clinical outcomes than those with aneuploid cancers. The pooled HR estimates were0.73 (P<0.0001) for DFS and 0.72 (P=0.0001) for OS, respectively.

CONCLUSION

This meta-analysis implies that DNA aneuploidy is a significant predictor for BC progression and survival, and should be focused on in the therapeutic planning.

Revisiting tumour aneuploidy - the place of ploidy assessment in the molecular era

Chromosome instability (CIN) is gaining increasing interest as a central process in cancer. CIN, either past or present, is indicated whenever tumour cells harbour an abnormal quantity of DNA, termed 'aneuploidy'. At present, the most widely used approach to detecting aneuploidy is DNA cytometry - a well-known research assay that involves staining of DNA in the nuclei of cells from a tissue sample, followed by analysis using quantitative flow cytometry or microscopic imaging. Aneuploidy in cancer tissue has been implicated as a predictor of a poor prognosis. In this Review, we have explored this hypothesis by surveying the current landscape of peer-reviewed research in which DNA cytometry has been applied in studies with disease-appropriate clinical follow up. This area of research is broad, however, and we restricted our survey to results published since 2000 relating to seven common epithelial cancers (those of the breast; endometrium, ovary, and uterine cervix; oesophagus; colon and rectum; lung; prostate; and bladder). We placed particular emphasis on results from multivariate analyses to pinpoint situations in which the prognostic value of aneuploidy as a biomarker is strong compared with that of existing indicators, such as clinical stage, histological grade, and specific molecular markers. We summarize the implications of our findings for the prognostic use of ploidy analysis in the clinic and for the theoretical understanding of the role of CIN in carcinogenesis.

Techniques for intraoperative radiation therapy for early-stage breast carcinoma

ABSTRACT 

Intraoperative radiation therapy (IORT) is a method of accelerated partial breast irradiation developed to replace other longer courses of radiotherapy with a single radiation session administered at the time of breast-conserving surgery. The purpose of this review is to summarize the advantages and disadvantages of breast IORT techniques that are currently available, as well to consider potential alternative techniques for breast IORT or ultra-short course breast radiotherapy. Furthermore, we highlight the published outcomes for the IORT treatment approaches including: electron therapy, superficial photon therapy and other techniques. Potential future directions of IORT are explored including novel IORT techniques utilizing intraoperative brachytherapy with in-room imaging and rapid treatment planning.

Is there a correlation between HPV and urinary bladder carcinoma?

AIMS

To detect human papilloma virus (HPV) infection, p21 oncogene, DNA content of urothelial cells in different bladder lesions with and without schistosomiasis and to correlate them with histopathological grade and stage.

METHODS

Eighty-five patients were enrolled: 25 chronic cystitis and 60 malignant bladder lesions; 15 schistosomal squamous cell carcinoma (SQCC), 45 urothelial carcinoma (transitional cell carcinoma TCC) schistosomal and non-scistosomal. Ten healthy individuals served as controls. Genotyping of HPV 6/11 and 16/18 were done using in situ hybridization and p21 protein expression by Immunohistochemical technique in formalin-fixed, paraffin-embedded tissues. DNA content of urothelial cells were stained with felugen stains and measured using Automated Image analysis System.

RESULTS

HPV DNA 6/11 and 16/18 expression was increased from cases of schistosomal cystitis with dysplasia to TCC with schistosomiasis compared to TCC and SQCC. The expression increased with statistical significance in invasive TCC and high-grade compared with superficial and low grade. Over-expression of p21 in invasive TCC group was compared with superficial TCC, high-grade TCC was compared low grade and TCC was compared with SQCC. Almost all cases of TCC associated with schistosomiasis exhibit aneuploid histogram compared to SQCC and all invasive TCC exhibited aneuploid histograms.

CONCLUSIONS

Both HPV infection and p21 gene abnormalities may contribute to bilharzial bladder carcinogenesis. DNA image cytometric features may predict stage progression in TCC. Expression of p21, DNA HPV 6/11 and 16/18 may be used as biological markers of bladder carcinoma.

Effects of DNA ploidy and S-phase fraction on fluorine-18 FDG uptake of primary breast cancer lesions

BACKGROUND

Flow cytometry (FCM) evaluating DNA content is emerging as the tool to monitor cell proliferation and malignant potential in several cancers such as stomach, lung, and salivary gland tumor. The purpose of this study was to correlate (18)F-FDG uptake of dual-time-point (DTP) positron emission tomography (PET) imaging with DNA ploidy and S-phase fraction (SPF) in primary breast cancer lesions.

PATIENTS AND METHODS

Seventy-two consecutive female patients (mean age ± SD, 52.7 ± 11.1 years; range, 28-81 years) had undergone (18)F-FDG DTP PET/computed tomography (CT) imaging for staging of breast malignancy in our institution during a 5-month period. FCM was performed on fresh-frozen samples of specimens obtained from surgery. (18)F-FDG uptake was then compared with DNA content.

RESULTS

Forty-four malignant lesions were included in this study. On FCM, DNA aneuploidy was detected in 14 lesions (31.8%). The maximum standardized uptake values (SUV(max1) and SUV(max2)) (SUV(max1), 6.8 ± 4.6 vs. 3.4 ± 2.4; P = .017), (SUV(max2), 7.9 ± 5.7 vs. 3.6 ± 2.7; P = .015) and retention index (RI) (12.8 ± 11.6 vs. 2.4 ± 10.8; P = .010) were significantly higher in DNA aneuploidy cancer than in DNA diploidy cancer. The value of RI (11.3 ± 11.5 vs. 2.6 ± 11.2; P = .022) was significantly higher in high SPF (> 15%) breast cancer than in low SPF (≤ 15%) breast cancer.

CONCLUSIONS

High (18)F-FDG uptake in breast cancer might be an indicator of DNA aneuploidy and high SPF. We propose that (18)F-FDG PET/CT imaging may be a noninvasive and useful tool for predicting the DNA content in breast cancer.

Can the centrosome be a marker for DNA ploidy in breast cancer?

Background:

The role of DNA ploidy in genomic instability of cancer cells and prognosis has been described in a number of studies. The role of the centrosome in cell cycle has also been reported.

Aim:

In this study, we aimed to investigate the correlation between the centrosome and DNA ploidy in breast cancer in a search for a cytologic predictive and prognostic marker.

Materials and Methods:

Cell prints were prepared from cell culture of mesothelial cells, fibroblast cell line MRC5 and breast cancer cell lines MCF7 and T47D. Indirect immunofluorescence was used with anti-γ-tubulin and centrosomes were quantified using a fluorescence microscope. DNA ploidy was scored with the DNA index analyzed by flow cytometry.

Results:

The normal mesothelial cells (94% of the cells with one detected centrosome) and MRC5 diploid cells (68% with two centrosomes) were used as quality controls. A correlation between the number of centrosomes and DNA ploidy was found in MCF7 cell lines (64% of the cells with a number of centrosomes ≥ 3). It was not observed in invasive breast cancer samples; however, the frequency of cells with centrosomes ≥ 3 was found to be slightly higher in DNA aneuploid samples than in DNA diploid samples (15% vs 13.3%).

Conclusion:

Quantification of centrosome appears to be correlated to DNA ploidy in breast cancer cell lines and slightly associated to DNA aneuploidy in invasive breast cancer. Studies analyzing a larger number of samples as well as morphological abnormalities of the centrosome are needed.

Expression of connexin 32 and connexin 43 in acute myeloid leukemia and their roles in proliferation

Connexins (Cxs), a conserved family of trans-membrane proteins, function in the organization of cell-cell communicatin via gap junctions in multicellular organisms. However, the role of Cxs in acute myeloid leukemia (AML) is poorly understood. In this study, we investigated the relationship between cell proliferation and expression of connexin 43 (Cx43) and connexin 32 (Cx32) mRNA and proteins in acute myeloid leukemia in vitro. Proliferation was observed using a growth curve and the rate of proliferation was detected by MTT assay in the acute myeloid leukemia cell lines OCI-AML3 and OCIM2. Cell cycle and cell proliferation index were assessed by flow cytometry analysis. The mRNA expression of the gap junction genes Cx43 and Cx32 was detected by RT-PCR. The expression of Cx43 and Cx32 proteins in the cell lines was analyzed by western blot analysis and immunofluorescence. The doubling time of OCI-AML3 and OCIM2 was 48 h and 36 h, respectively. In OCIM2, the percentage of cells in the S phase fraction was 59.47±9.6%, and the proliferation rate was 78.12±8.9%; however, in OCI-AML3, the percentage of cells in the S phase was 24.95±5.8%, and the proliferation rate was 35.21±6.7%. At the mRNA level, both cell lines expressed Cx43 and Cx32, and there was no significant difference in the expression of Cx43 and Cx32 mRNA in the two cell lines. At the protein level, there was a significant difference in the expression of Cx43, but not of Cx32. The proliferation ability of OCIM2 was higher than OCI-AML3, and OCIM2 exhibited higher Cx43 western blot and fluorescence intensities compared with OCI-AML3. The results suggest that a higher expression of Cx43 in AML cells may play a significant role in the proliferation ability.

Prognostic significance of DNA image cytometry in Libyan breast cancer

BACKGROUND

We evaluated the relation of nuclear DNA content and clinicopathological features and prognosis in primary breast cancer of female Libyan patients with variable stage and grade and different treatment regimes.

PATIENTS AND METHODS

Histological samples from 104 patients of breast carcinoma were retrospectively studied by computerized nuclear DNA cytometry. Isolated nuclei from paraffin sections were stained with Feulgen stain and DNA was measured using a computer-assisted image analysis cytometry system. In each case, 200 nuclei were measured and the DNA histograms, S phase fraction (SPF) and number of cells above 5c and 9c were determined. We applied different approaches in the analysis of DNA to compare the DNA histograms with different clinicopathological features and survival.

RESULTS

The mean of DNA ploidy mode for all tumors was 3.43; 82.7% of tumors were aneuploid and 17.3% were diploid. The median SPF was 3.5% for DNA diploid and 13.5% for DNA aneuploid tumors. DNA aneuploid tumors and high SPF were associated with advanced stage, distant metastasis, high histological grade and lymph node involvement. The SPF was also associated with large tumor size and with younger patients (<50 years). In the overall population (median follow-up 51 months), patients with aneuploid DNA histograms and high SPF values had shorter survival times than those with diploid DNA histograms and low SPF values (p = 0.001, p < 0.0001, respectively). Also, short survival was associated with a multiploid DNA histogram and with DNA aneuploid cells ≥5 cells (p < 0.0001, p = 0.001, respectively). In a Cox multivariate analysis, DNA ploidy (p = 0.010), age (p = 0.038) and clinical stage (p = 0.001) were independent predictors of overall survival, and DNA ploidy (p = 0.018) and clinical stage (p = 0.001) also proved to be independent predictors of disease-specific survival. The SPF cutoff point of 11% might be applied to separate patients into good and poor prognosis groups.

CONCLUSIONS

DNA image cytometry with careful analysis of the histograms may provide valuable prognostic information in Libyan breast cancer, with potential clinical implications in patient management, particularly in predicting the patients at high risk for metastasis and recurrence who should be considered as candidates for combined adjuvant therapy.

Spontaneously occurring micronuclei in infiltrating ductal carcinoma of breast: a potential biomarker for aggressive phenotype detection?

Chromosomal instabilities (CIN) manifesting as structural or numerical alterations in the chromosomes are common in malignancies like breast cancer. Assessment of CIN in breast cancer may help to understand its etiopathogenesis. Micronucleus (MN) scoring and aneuploidy have been used to assess the presence of CIN in lymphocytes of various malignancies in the past. In this study, spontaneously occurring MN were counted in epithelial cells on fine needle aspiration cytology (FNAC) smears from 50 patients with benign and malignant breast lesions. Further, the ploidy status and S-phase fraction (SPF) of the samples was determined by flow cytometry. All these were then correlated with grades of breast cancer at cytology. Most IDC cases showed variable number of MN (n = 16, MN mean = 9.3), in contrast to the benign lesions (n = 26) where they were consistently absent. Aneuploidy and SPF analysis also showed a significant difference between benign (n = 10, mean DNA index [DI] = 0.96 ± 0.04, mean SPF= 8.07% ± 2.93) and malignant (n = 10, mean DI = 1.5 ± 0.41, mean SPF = 25.05% ± 10.35) lesions. On statistical analysis, a positive correlation was observed between the grades of IDC and presence of aneuploidy and high SPF (P-values < 0.05); however, the difference between the MN scores of grade 2 and 3 cancers was not significant. The study suggests that MN scoring and aneuploidy may be used to assess the presence of underlying CIN in IDC on FNAC smears. Further, collectively they may be explored for their role as biomarkers for predicting the tumor behavior in the breast cancer patients.

Flow cytometric analysis of DNA ploidy and S-phase fraction in primary localized myxofibrosarcoma: correlations with clinicopathological factors, Skp2 expression, and patient survival

BACKGROUND

Histological assessment for prognostication of myxofibrosarcomas remains challenging. We previously reported independent prognostic value of Skp2, an oncoprotein promoting S-phase progression (Clin Cancer Res 2006;12:487-98).

METHODS

We evaluated S-phase fraction (SPF) and ploidy of myxofibrosarcomas and the association between SPF and Skp2. Flow cytometric findings were analyzed for 75 cases and correlated with clinicopathological factors, Skp2 labeling index (LI), metastasis-free survival (MeFS), and overall survival (OS).

RESULTS

Forty-seven and 28 cases were classified as diploid and nondiploid, respectively. High SPF (>or=20%) was detected in 32 of 61 interpretable cases. Skp2 overexpression (LI >or= 10%) was seen in 36 of 72 cases with scoring. Nondiploidy correlated with higher French Federation of Cancer Centers (FNCLCC) grades (P = .006), remarkable necrosis (P = .010), and Skp2 overexpression (P = .018). Noticeably, SPF was significantly related to Skp2 LI (P < .001, r = .458), FNCLCC grade, American Joint Committee on Cancer stage, and mitotic rate. Nondiploidy predicted shorter OS (P = .0045) and MeFS (P = .0489), whereas SPF >or= 20% was only associated with inferior MeFS (P = .0252). In multivariate analyses, nondiploidy independently correlated with both OS (P = .020, RR = 3.337) and MeFS (P = .013, RR = 5.780), together with Skp2 overexpression (P = .014 for OS; P = .017 for MeFS) and disease-positive margins (P = .004 for OS; P = .002 for MeFS).

CONCLUSION

Skp2 promotes S-phase progression in myxofibrosarcomas. SPF provides no independent prognostic usefulness; it is probably overshadowed by Skp2. Nondiploidy adds another predictive value to Skp2 overexpression and disease-positive margins in prognostication.

Characterization of Primary Breast Carcinomas Grown in Three-Dimensional Cultures

BACKGROUND

The process of progression and spread of cancer is not easily replicated in animal models and is difficult to examine in vitro. This is particularly true for human primary breast carcinoma cells, whose in vitro growth is shown to be limited to one or two passages in monolayer culture. Three-dimensional (3D) growth of breast cancer cells suggests that cell aggregates grown in this manner have many similarities to in vivo behavior.

MATERIALS AND METHODS

Primary tumors obtained from five breast cancer patients were grown in 3D cultures using the rotating-wall vessel bioreactor. Tumor aggregates were assessed for DNA ploidy, cell cycle kinetics, and expression of tumor markers and cytokines. Comparisons between fresh tumor cells and 3D aggregates were performed.

RESULTS

All five breast cancers were found to be aneuploid after 3D culture, with elevated S-phase fractions. Reverse transcription-polymerase chain reaction analyses revealed mRNA expression of HER2/neu, H-ras, K-ras, p53, transforming growth factor-alpha, transforming growth factor-beta, interleukin-1, and interleukin-6 in 3D-grown tumor cells; in most cases, expression appeared increased when compared with mRNA obtained from freshly isolated primary tumor cells.

CONCLUSIONS

After prolonged 3D growth in the rotating wall bioreactor, complex tissue-like constructs of primary breast tumor cells exhibited significantly increased proliferative activity in conjunction with oncogene activation and developed into aggressive aneuploid populations.

Lymph node status as a guide to selection of available prognostic markers in breast cancer: the clinical practice of the future?

Prognosticators evaluating survival in breast cancer vary in significance in respect to lymph node status. Studies have shown e.g. that HER2/neu immunohistochemistry or HER2/neu gene amplification analysis do perform well as prognosticators in lymph node positive (LN +) patients but are less valuable in lymph node negative (LN -) patients. We collected data from different studies and tried to evaluate the relative significance of different prognosticators in LN+/LN- patient groups. In LN+ patients HER2/neu and E-cadherin immunohistochemistry were the statistically most significant prognosticators followed by proliferation associated features (mitotic counts by SMI (standardised mitotic index) or MAI (mitotic activity index), or S-phase fraction). Bcl-2 immunohistochemistry was also significant but p53 and cystatin A had no significance as prognosticators. In LN- patients proliferation associated prognosticators (SMI, MAI, Ki-67 index, PCNA immunohistochemistry, S-phase fraction) are especially valuable and also Cathepsin D, cystatin A, and p53 are significant, but HER2/neu or bcl-2, or E-cadherin less significant or without significance. We find that in studies evaluating single prognosticators one should distinguish between prognosticators suitable for LN+ and LN- patients. This will allow the choice of best prognosticators in evaluating the prospects of the patient. The distinction between LN+ and LN- patients in this respect may also be of special value in therapeutic decisions.

Prognostic impact of Deoxyribonucleic acid (DNA) image analysis cytometry and immunohistochemical expression of Ki67 in surgically resected non-small cell lung cancers

BACKGROUND

The aim of the present study was to evaluate the prognostic significance of DNA ploidy and Ki67 expression in non-small cell lung carcinoma (NSCLC).

METHODS

This prospective study included 96 patients with stages I-IIIA NSCLC who underwent surgical excision. DNA image analysis cytometry was applied on imprints. Calculation of the DNA index (DI) and the 5c exceeding rate (5cER) was performed and the histograms were classified as peridiploid, peritetraploid, and x-ploid-multiploid. The Ki67 immunoreactivity was determined according to the avidin-biotin complex immunoperoxidase method.

RESULTS

DNA histogram classification disclosed 30 peridiploid cases, 15 peritetraploid and 51 x-ploid-multiploid. Forty-eight cases (50%) had 5cER > 5%. The Ki67 immunoreactivity was below 25% in 53 tumors (62.4%) and above 25% in 32 (32.6%). Our results revealed the existence of a statistically significant relationship of DNA ploidy with nodal status (p = 0.042) and grade (p = 0.005). Adenocarcinomas and large cell carcinomas were more frequently encountered in x-ploid-multiploid tumors as compared to squamous cell carcinomas, which were more frequently peridiploid (p = 0.003). 5cER showed statistically significant association with nodal status (p = 0.037). Univariate analysis with respect to survival revealed significant association with stage (p < 0.001), nodal status (p < 0.001), tumor status (p < 0.001), DNA ploidy (p = 0.008) and 5cER (p = 0.0124). Multivariate analysis revealed stage and ploidy status as independent factors: peridiploid tumors were associated with better survival as compared to x-ploid-multiploid tumors (p = 0.022).

CONCLUSION

Our results suggest that DNA ploidy, as determined by image analysis, provides an independent prognostic parameter for patients with NSCLC and thus, could be used to identify a subset of patients with more aggressive tumors.

Deoxyribonucleic acid content as an indicator of progression of squamous cell carcinogenesis in the esophagus: Comparative analysis on imprint-cytospin and tissue section preparation

BACKGROUND

The purpose of this study was to explore the potential use of image analysis on tissue sections preparation as a predictive marker of early malignant changes during squamous cell (SC) carcinogenesis in the esophagus. Results of DNA ploidy quantification on formalin-fixed, paraffin-embedded tissue using two different techniques were compared: imprint-cytospin and 6 microm thick tissue sections preparation.

METHODS

This retrospective study included 26 surgical specimens of squamous cell carcinoma (SCC) from patients who underwent surgery alone at the Department of Surgery in CHUV Hospital in Lausanne between January 1993 and December 2000. We analyzed 53 samples of healthy tissue, 43 tumors and 7 lymph node metastases.

RESULTS

Diploid DNA histogram patterns were observed in all histologically healthy tissues, either distant or proximal to the lesion. Aneuploidy was observed in 34 (79%) of 43 carcinomas, namely 24 (75%) of 32 early squamous cell carcinomas and 10 (91%) of 11 advanced carcinomas. DNA content was similar in the different tumor stages, whether patients presented with single or multiple synchronous tumors. All lymph node metastases had similar DNA content as their primary tumor.

CONCLUSIONS

Early malignant changes in the esophagus are associated with alteration in DNA content, and aneuploidy tends to correlate with progression of invasive SCC. A very good correlation between imprint-cytospin and tissue section analysis was observed. Although each method used here showed advantages and disadvantages; tissue sections preparation provided useful information on aberrant cell-cycle regulation and helped select the optimal treatment for the individual patient along with consideration of other clinical parameters.