Prognostic significance of the DNA content of human breast cancer

Silencing of E2F3 suppresses tumor growth of Her2+ breast cancer cells by restricting mitosis

The E2F transcriptional activators E2F1, E2F2 and E2F3a regulate many important cellular processes, including DNA replication, apoptosis and centrosome duplication. Previously, we demonstrated that silencing E2F1 or E2F3 suppresses centrosome amplification (CA) and chromosome instability (CIN) in Her2+ breast cancer cells without markedly altering proliferation. However, it is unknown whether and how silencing a single E2F activator, E2F3, affects malignancy of human breast cancer cells. Thus, we injected HCC1954 Her2+ breast cancer cells silenced for E2F3 into mammary fat pads of immunodeficient mice and demonstrated that loss of E2F3 retards tumor growth. Surprisingly, silencing of E2F3 led to significant reductions in mitotic indices relative to vector controls, while the percentage of cells undergoing S phase were not affected. Nek2 is a mitotic kinase commonly upregulated in breast cancers and a critical regulator of Cdk4- or E2F-mediated CA. In this report, we found that Nek2 overexpression rescued back the CA caused by silencing of shE2F3. However, the effects of Nek2 overexpression in affecting tumor growth rates of shE2F3 and shE2F3; GFP cells were inconclusive. Taken together, our results indicate that E2F3 silencing decreases mammary tumor growth by reducing percentage of cells undergoing mitosis.

Disparities in breast cancer outcomes between Caucasian and African American women: a model for describing the relationship of biological and nonbiological factors

Breast cancer is the most common malignancy in women in the United States but significant disparities exist for African American women compared to Caucasian women. African American women present with breast cancer at a younger age and with a greater incidence under the age of 50 years, develop histologically more aggressive tumors that are at a more advanced stage at presentation, and have a worse disease-free and overall survival than Caucasian women. The biological characteristics of the primary tumor play an important role in determining the outcome of the disparity, and significant differences have been identified between African American and Caucasian breast cancer in steroid receptor and growth factor receptor content, mutations in cell cycle components, chromosomal abnormalities, and tumor suppressor and other cancer genes. The consequences of the biological factors are influenced by a variety of nonbiological factors, including socioeconomic, health care access, reproductive, and confounding factors. The nonbiological factors may act directly to enhance (or inhibit) the consequences of the biological changes, indirectly to facilitate outcome of the disparity, or as a cofounding factor, driving the association between the biological factors and the disparity. The prevention and management of the disparities will require an understanding of the relationship of biological and nonbiological factors. The present review was undertaken to promote this understanding by describing the biological basis of the four major disparities - early age of onset, more advanced stage of disease, more aggressive histologic changes, and worse survival - and the important relationship to the nonbiological factors. A model is proposed to provide a comprehensive view of this relationship, with the goal of facilitating an understanding of each disparity and the issues that need to be addressed to eliminate the disparity.

Selective destabilization of tumor cells with pulsed electric and magnetic sequences: a preliminary report

BACKGROUND

Various studies in vitro suggest that low electric and magnetic fields may modify cancer cell growth and recent studies in vivo have revealed anti-tumoral effects. After screening different tumor cell lines, we identified specific sequences of localized magnetic and electric fields (MESQ) that reduce cancer cell survival in vitro. This finding led us to design an experiment to determine the actual efficacy of above sequences in selectively destabilizing tumor cells and their effect on healthy cells.

MATERIALS AND METHODS

We exposed the MCF7 cancer cell line and normal fibroblasts to MESQ for 1, 2, 3 and 6 hours, evaluating cell survival and induction of apoptosis.

RESULTS

Exposure to MESQ reduced MCF7 survival, inducing apoptosis in a timedependent way, whereas fibroblasts were completely unaffected.

CONCLUSION

These results have promising implications for the treatment of cancer and warrant further research.

Thymidine labeling index: prognostic role in breast cancer

The aim of this study is to evaluate the prognostic role of thymidine labeling index in patients with breast cancer. Cellular proliferation rates in 155 breast cancer specimens were investigated by 3H-thymidine labeling index (3H-TLI). Median age was 47 years (range: 23-76). At presentation, 11 patients (7.1%) had stage I disease, 76 (49%) had stage II, 64 (41.3%) had stage III disease, and 4 (2.6%) had metastatic involvement. Patients were placed in 2 groups based on their proliferative indices. The cut-off level was assigned as the median TLI value of the whole group. Correlations between proliferative activity of the tumors based on 3H-TLI levels and various previously established prognostic factors, as well as the influence of proliferative activity on survival as a clinical outcome, were analyzed. The mean and median TLI values for the whole group of patients were 4.36 +/- 4.96% and 2.76% (range: 0-23.6), respectively. There was a significant association of nuclear grade with TLI (P = 0.04). Patients who were alive with no sign of disease at the final follow-up examination had a significantly lower median TLI rate than those who were either alive with disease or those who had eventually died with disease progression (3.7% versus 1.9%, respectively; P = 0.04). Patients with locally advanced disease (N2 + N3 involvement) had a significantly higher median TLI rate than those with local nodal involvement (N1) (3.4% versus 1.7%, respectively, P = 0.026). Furthermore, TLI levels showed a significant association with overall survival in patients with node-negative disease (P = 0.02). Based on the results of this study, it can be concluded that TLI plays a significant prognostic role in a subset of patients with node-negative breast cancer. Furthermore, TLI appears to have a predictive value for the clinical outcome of patients with breast cancer. These findings may justify a more aggressive therapeutic approach in patients with high TLI levels. Further large-scale, prospective studies are required before a definite conclusion can be reached.reached.

Molecular evolutionary patterns in breast cancer

Geno-phenotypic patterns of pre-invasive and invasive lobular breast cancers and infiltrating ductal carcinomas of low, intermediate, and high grade are reviewed. One of the main differences between lobular breast cancers and ductal carcinomas is the presence of inactivating E-cadherin gene mutations in lobular breast cancers. In many other respects, lobular breast cancers and low-grade ductal carcinomas exhibit similar geno-phenotypic profiles. The development of p53 dysfunction may be a hallmark of infiltrating ductal cancers of intermediate and high grade. Sequential Her-2/neu and ras abnormalities define a subset of aggressive high-grade tumors, and the development of Rb dysfunction may define a separate subset of aggressive ductal cancers. Based on these observations, a branching molecular evolutionary model for the development and progression of breast cancer is proposed.

Two-color, cytokeratin-labeled dna flow cytometric analysis of 332 breast cancers: lack of prognostic value with 12-year follow-up

CONTEXT

DNA flow cytometry of breast cancer is a proposed tumor marker of prognostic significance that is of controversial clinical utility because of lack of standardization and confirmatory studies.

OBJECTIVE

To evaluate the prognostic significance of the more informative technique of multiparametric 2-color DNA flow cytometry as recommended by the 1992 DNA Cytometry Consensus Conference.

DESIGN

Three hundred thirty-two breast carcinomas with 7 to 12 years of follow-up were prospectively analyzed as fresh tumors that were mechanically dissociated into whole cell suspensions. These suspensions were dual fluorescence-labeled with propidium iodide (DNA) and antibodies to cytokeratin (epithelium) and leukocyte common antigen (internal leukocyte control) for gated analysis of subpopulations. Multicycle software with histogram-dependent algorithms employing background, aggregate, and debris correction were used in DNA and cell-cycle quantitation. Data were analyzed according to the DNA Flow Cytometry Consensus Conference recommendations.

RESULTS

DNA ploidy and proliferation stratified into 3 categories were not predictive of overall or disease-free survival. Sixty-five percent of tumors were nondiploid, and 35.4% were diploid. Two hundred six tumors were able to be evaluated for synthesis-phase fraction (SPF) analysis, with 74 of 206 cases in the low range (<13.4%), 36.4% in the intermediate range (>13.5 to <25.4%), and 27.6% in the high SPF (>25.5%) category. Aneuploid tumors tended to have a higher SPF. Univariate survival analysis showed prognostic significance of the following: tumor size, stage, TNM components, vascular invasion, nuclear grade, and histologic grade. Only T classification, presence of positive axillary lymph nodes, and distant metastases were significant independent predictors of survival in multivariate Cox regression models. Age and hormone receptor status showed no prognostic significance. Synthesis-phase fraction was significantly correlated with tumor size, stage, T classification, nuclear and histologic grade, presence of estrogen or progesterone receptors, and axillary lymph node status. None of the histologic parameters showed any significant association with DNA aneuploidy, except for high nuclear and histologic grade and the absence of estrogen receptors.

CONCLUSIONS

Despite the use of state-of-the-art processing and flow cytometry analytic techniques, DNA ploidy and proliferation measurements were not predictive of survival in any stage of breast cancer. However, select histopathologic parameters and TNM stage were significant predictors of survival in univariate and multivariate analyses. We conclude that DNA ploidy and proliferation measurements do not provide significant prognostic information for clinicians to integrate into therapeutic decision making for patients with breast cancer.

Preoperative assessment of prognostic factors in breast cancer

The adoption of preoperative diagnostic strategies involving fine needle aspiration cytology (FNAC) or core biopsy is well established, allowing the planning of operating lists and bed occupancy and patient involvement in therapeutic management. In addition to diagnosis, however, pathologists are increasingly being asked to provide pathological prognostic information from preoperative samples. This leader describes techniques for predicting prognosis and response to treatment on these specimens and some of the problems inherent in the determination of prognosis on small samples. For example, although histological grade can be assessed relatively reliably on either core or FNAC samples, the evaluation of tumour type (which includes an overall assessment of the architecture of a given tumour) may be less reliable on small preoperative samples. Other well recognised histological prognostic factors, such as vascular channel invasion or tumour size, cannot be determined accurately on small preoperative samples. For those patients who might benefit from neoadjuvant treatment, predicting the response to such treatments--for example, by the assessment of oestrogen receptor status--can readily be performed on either core biopsy or FNAC. In the future, other molecular markers such as C-erbB-2 might also prove beneficial in predicting response to newly developed treatments.

Fluorescence in situ hybridization assessment of chromosome 8 copy number in stage I and stage II infiltrating ductal carcinoma of the breast

A total of 34 cases of infiltrating ductal carcinoma of the breast, not otherwise specified (NOS), were selected, based on the clinical stage of the disease (17 cases stage I and 17 cases stage II). The histologic grade and the DNA content of each tumor were evaluated. Each specimen was analyzed and blinded cytogenetically for the frequency of chromosome 8 copy number using fluorescence in situ hybridization (FISH). Among the informative samples, 16 cases were disomic (47%) and 18 cases (53%) were trisomic. Of the 16 disomic tumors, 13 cases (81%) were classified clinically as stage I disease and 3 cases (19%) were stage II disease. Of the 18 trisomic tumors, 4 cases (22%) were stage I, and 14 cases (78%) were stage II. Microscopically, all trisomic tumors were of high histologic grade and aneuploid when analyzed by flow cytometry. We inferred from these data that a subset of infiltrating ductal carcinomas (NOS) is characterized by chromosome 8 trisomy. This chromosomal abnormality correlates well with other markers that predicate aggressive biological behavior of the tumor. While this observation needs to be further extended, the data suggest that chromosome 8 copy number may be used as a possible marker to identify a subgroup of patients with infiltrating ductal carcinoma associated with a poor prognosis.

Flow cytometric DNA hypertetraploidy is associated with unfavourable prognostic features in breast cancer

AIM

Breast tumours with a DNA content higher than 4N (hypertetraploidy) are not well characterised. The aim of this study was to evaluate the clinical and biological characteristics of 51 hypertetraploid breast carcinomas selected from a series of 860 consecutive cases analysed by flow cytometry.

METHODS

The clinicopathological characteristics of the hypertetraploid group were compared with those of a control group of 138 non-hypertetraploid breast carcinomas. Breast tumours from patients submitted to surgery as primary therapeutic approach (15 hypertetraploid and the 138 non-hypertetraploid) were TNM staged and classified according to the histological type and grade. The remaining 36 patients had advanced neoplastic disease at presentation and were classified by cytological criteria only. DNA flow cytometric analysis was performed on fresh-frozen samples stained with propidium iodide. Hormone receptors were analysed by immunocytochemistry.

RESULTS

The incidence of hypertetraploid breast tumours was 5.9% (51 of 860). All the patients were women and the mean age at diagnosis was 65 years. There was a family history of breast cancer in 21.6% of cases. In the group of operated patients, 33.3% had pT3 tumours and 53.3% had axillary lymph node metastases. All but one tumour were invasive ductal carcinomas; the remaining was an invasive papillary carcinoma. Ten (66.7%) tumours were classified as poorly differentiated carcinomas. Oestrogen and progesterone receptors were negative in 33 (64.7%) and 38 (74.5%) tumours, respectively. At last follow up, 35 (72.9%) patients were alive, while 13 (27.1%) died of disease within three years of diagnosis. Statistical comparison of the clinicopathological features of hypertetraploid v non-hypertetraploid breast carcinomas yielded a significant difference in tumour size (p < 0.001), histological grade (p < 0.001), hormone receptor status (p < 0.001), and overall survival (p < 0.001) between the two groups.

CONCLUSION

Flow cytometric DNA hypertetraploidy is related to clinicopathological features of breast cancer usually associated with unfavourable prognosis.

Histopathology grading in small breast cancers < or = 10 mm--results from an area with mammography screening

Histopathological malignancy grading using the Bloom-Richardson classification of ductal cancers was performed for 248 invasive ductal breast cancers < or = 10 mm operated 1978-1985. There were significantly more grade 1 lesions in the prevalence screening round. Grade 3 was correlated with aneuploidy, higher S-phase (SPF), and more receptor negative tumours. There were also significantly more positive lymph nodes in grade 3 lesions, 18% compared to 5% and 12% respectively for grades 1 and 2 (p < 0.05). In life table analysis for survival, when the high risk group of grade 3 lesions was compared to the grade 1 and 2 lesions combined, five-year disease-free survival was 84.6% vs. 99.1% (p < 0.001). With good training and care from the pathologist, malignancy grading seems useful for prognostication of eventual recurrence and death. In tumours 10 mm or smaller only grade 3 lesions need to be included in follow-up systems and should probably have adjuvant treatment. Malignancy grading is especially good in small ductal breast cancers where grading can always be performed while other prognostic determinations are hampered by shortage of material. Lymph node positivity is also low in this group.

S-phase fraction identifies high-risk subgroups among DNA-diploid breast cancers

The prognostic value of DNA content measured by means of flow cytometry was analyzed in formalin-fixed, paraffin-embedded samples from 231 breast cancer patients treated between 1984 and 1988, with a mean follow-up period of 55 months. We followed the guidelines of a Consensus Meeting held on this issue in Maine, USA, in 1992. DNA-diploid and -aneuploid tumors were evaluated separately for the fraction of cells in S-phase (SPF) contained in them, this being divided into three groups ('high', 'intermediate', and 'low'), defined by the 25th and 75th centile of the SPF-distribution corresponding to either DNA-diploid or DNA-aneuploid tumors. Unequivocally readable histograms were obtained from 174 samples (75.3%). A high SPF in diploid tumors was significantly associated with a higher recurrence rate (p = 0.015), a shorter disease-free survival (p = 0.014), advanced (IIIB) clinical stage (p = 0.034), and almost significantly with total survival (p = 0.055). In a multivariate Cox regression analysis, a high SPF in diploid tumors retained its independent prognostic power, being significantly associated with a shorter disease-free survival (p = 0.00049) and total survival (p = 0.0077). It also allowed to identify a subgroup with an ominous prognosis among patients < or = 50 years of age with early stage tumors. Our results fully validate the recommendations of the 1992 Maine Consensus Meeting.

Flow cytometry in node-positive breast cancer: cancer and leukemia group B protocol 8869

This report describes a companion flow cytometry study (Cancer and Leukemia Group B (CALGB)--8869) using tumors derived from patients enrolled in a large randomized clinical trial (CALGB-8541) performed on 1,572 patients with early stage, node-positive breast cancer. The CALGB initiated an adjuvant breast cancer trial in 1985 to determine if dose intensification (dose of drug per unit time) of chemotherapy was related to relapse-free and overall survival. Patients were randomized by pretreatment clinical variables to one of three different dosage regimens of chemotherapy. Using a tumor enrichment procedure, 442 paraffin-embedded blocks were analyzed by flow cytometry, and S-phase fraction (SPF) was analyzed by three different methods. Ploidy analysis was performed using standard procedures. Tissue from 90% of the patients was suitable for ploidy analysis, whereas only 68% could be assessed for SPF. With a median follow-up time of 80 months, our results show that ploidy status had no clinical utility, whereas high SPF predicted poorer overall survival. The rectangular fit model for SPF was more predictive of outcome than both the area fit model and a computer fit model (modfit) for SPF. In univariate analysis, patients with a low SPF (< 10%) had a better prognosis than those patients with a high SPF (> 10%), but they responded equally well to the different treatment regimens. Patients with high SPF (> 10%) had longer relapse-free and overall survival to high dose chemotherapy compared to low or standard dose chemotherapy. Multivariate analysis indicated that treatment intensity as well as the number of positive nodes, tumor size, steroid receptor status, and c-erb B-2 expression were significant in predicting overall and disease-free survival. The multivariate analysis, however, revealed that SPF was significant in predicting overall but not disease-free survival, but there was no longer any relationship among SPF, dose intensity, and outcome.

A search for prognostic factors in cancer of the pancreatic head: the significance of the DNA ploidy pattern

Using flow cytometry after the nuclear isolation and staining of tissue specimens, the significance of the DNA ploidy pattern as a prognostic factor in cancers of the head of the pancreas has been evaluated in 33 patients who underwent a pancreatic cancer resection. In addition to the DNA ploidy pattern, the size of the tumour, regional lymph node involvement, the tumour's histopathological grade and the results of a curative resection were also evaluated as prognostic factors. The results of a univariate analysis revealed that the survival rate was significantly higher for patients with a diploid tumour (n = 20) than for patients with an aneuploid tumour (n = 13) (P < 0.001). Furthermore, survival rates were significantly better for patients with a T1 tumour than with a T2 or T3 tumour (P < 0.001), for patients without positive lymph node involvement than for those with positive lymph nodes (P < 0.001), for patients with well-differentiated adenocarcinomas (G1) than for those with moderately differentiated (G2) or poorly differentiated (G3) adenocarcinomas, and for patients who underwent a curative resection than for those who underwent a non-curative resection (P < 0.005). A multivariate analysis revealed significant prognostic differences in the DNA ploidy pattern (P < 0.001), the frequency of a curative resection (P < 0.001), regional lymph node involvement (P < 0.05), and in the tumour's histopathological grading (P < 0.05) but not its size. This study has found the DNA ploidy pattern to be the most significant prognostic factor (chi 2 value: 38.1).

Reproducibility in DNA flow cytometric analysis of breast cancer: comparison of 12 laboratories' results for 67 sample homogenates

Flow cytometric (FCM) DNA analysis yields information on ploidy status and the S-phase fraction (SPF), variables of prognostic importance in breast cancer. The clinical value of the SPF is currently being evaluated in prospective randomized trials. The widespread use of FCM DNA analysis emphasizes the importance of reproducibility (both intra- and interlaboratory). In this study, 67 nuclear suspensions of breast cancer samples were analyzed by 12 laboratories routinely performing FCM DNA analysis in breast cancer. No general guidelines were imposed; each laboratory used its own standard protocols. For DNA ploidy status (diploid vs. non-diploid), agreement was complete for 79% (53/67) of the samples, compared with 64% (43/67) of samples when tetraploidy was considered [i.e., euploid (diploid+tetraploid) vs. aneuploid (the remaining non-diploid)]. For the SPF, pairwise comparison of the results of all 12 laboratories yielded a mean Spearman's rank correlation of 0.78 (range: 0.54-0.93). For those 39 samples being categorized in low or high SPF by all laboratories, all agreed in 14 samples (36%). Similar patterns were obtained with kappa measures, agreement being good for ploidy status (diploid vs. non-diploid; overall kappa = 0.87 and 0.74 for euploid vs. aneuploid), but moderate for the SPF [overall kappa = 0.47 (for low SPF vs. high SPF vs. "no SPF reported")]. Discrepancies were chiefly attributable to differences in the categorization of the S-phase values, rather than in FCM procedures, other critical differences being in the detection and interpretation of near-diploid and small non-diploid cell populations, the definition of tetraploidy, and the choice and execution of the method used for S-phase estimation. Based on the observations of this study, detailed guidelines for FCM analysis and interpretation of data are proposed in the Appendix. Some issues remain, however, e.g., to standardize a method for S-phase calculation and tetraploid definition.

DNA index and S phase fraction in uveal malignant melanomas

AIMS

To predict 5 year survival in patients with uveal malignant melanomas DNA indices were studied.

METHODS

Using 45 paraffin embedded uveal malignant melanomas, the DNA index and S phase fraction of each tumour were the predictor variables recorded.

RESULTS

Using the Cox proportional hazards model, aneuploid tumours and tumours which had an S phase fraction greater than 4% were significant predictors of early death. In order to demonstrate a biological gradient between a larger DNA index and shorter survival time, linear regression and transformed linear regression models were used. However, no such gradient could be demonstrated.

CONCLUSION

Although this study shows promise for the use of DNA studies in the prognosis of uveal malignant melanoma, the exact role of these techniques remains to be determined.

Relationship between low estrogen receptor values and other prognostic factors in primary breast tumors

BACKGROUND

The current study compared the immunocytochemical expression of estrogen (ER) and progesterone (PgR) receptors by malignant breast cells to the hormone receptor concentrations reported from radioligand assays. These values were examined in relation to DNA ploidy and the fraction of cells in S phase.

METHODS

ER and PgR concentrations, DNA ploidy, and S-phase fractions were measured by standard techniques with 124 samples of invasive ductal carcinoma. Suspensions of tumor cells were examined by immunocytochemical assay (ICA) for the percentages of ER and PgR positive cells.

RESULTS

Twenty-six of the 38 tumors from patients 50 years of age or younger were classified as high S-phase fraction, and 28 tumors had aneuploid levels of DNA. The 20 ER positive tumors each contained less than 100 fmol/mg. Thirty-nine of the 86 tumors from patients older than 50 years were classified as high S phase, and 41 were aneuploid. Sixty-five samples were considered ER positive by radioligand assay. ICA showed that tumors in either age group with less than 40 fmol/mg did not contain ER positive cells. The proportion of samples with PgR levels between 10 and 100 fmol/mg was small, and fewer PgR positive tumors were categorized as negative when examined by ICA for receptor containing cells. The reclassification of the hormone receptor status of a tumor based on ICA appeared to be independent of S-phase and ploidy values.

CONCLUSIONS

Tumors that are classified as ER or PgR positive based on accepted cutoff values for radioligand assays may actually be receptor negative because the tumors do not appear to contain receptor positive cells.

Flow cytometric DNA ploidy defines patients with poor prognosis in node-negative breast cancer

Flow cytometric DNA analysis was performed on fine-needle aspirates from frozen tumour biopsies from 421 node-negative, non-adjuvantly-treated breast-cancer patients with a median observation time of 6.75 years. Among premenopausal patients (n = 175), those having at least one DNA "hypoploid" subpopulation defined as DNA index (DI) < 0.96 or 1.44 < or = 1.92 (n = 81) were characterized by early recurrences (log-rank p = 0.05), Wilcoxon p = 0.007), poor overall survival (OS) (p < 0.001) and poor survival after recurrence (p < 0.001). In the postmenopausal group (n = 246), there were no significant difference among 7 different DI classes regarding either recurrence-free survival (RFS) or OS. S-phase fraction (SPF), divided into quartiles, predicted OS in premenopausal patients only (p = 0.02). Conventional multivariate Cox analysis of OS in the premenopausal group revealed hypoploidy to be the only independent prognostic factor involving a relative risk (RR) of 22.8. Age < or = 40 years was of marginal significance, whereas SPF, histological grade (WHO), oestrogen and progesterone receptor (PgR) content, tumour size and number of lymph nodes removed were excluded from the model. Application of the conventional Cox model to the premenopausal group regarding RFS was found inappropriate due to lack of proportionality of the hazards of hypoploidy due to lack of proportionately of the hazards of hypoploidy, SPF and histological grade. However, introduction of time-dependent co-variates using 2 years as cut-off level showed hypoploidy with a RR of 3.52 and age < or = 40 years with a RR of 3.28 to be independent prognostic factors. In the postmenopausal group, the conventional Cox model identified the number of lymph nodes removed to be the only independent prognostic factor regarding RFS as well as OS, whereas SPF < 9% (lowest quartile) was of marginal significance in RFS analysis. Hypoploidy was correlated to high SPF, low PgR content and low differentiation, indicating that hypoploid tumours proliferate rapidly and hormone-independently. These patients may therefore benefit from adjuvant chemotherapy administered while tumour burden and risk of drug resistance are still low.

DNA ploidy and S-phase fraction in medullary carcinoma of the breast--a flow cytometric analysis using archival material

In a population of 110 primary breast cancers with medullary features, registered in the Danish Breast Cancer Cooperative Group (DBCG) from 1977-82, we have determined ploidy and S-phase fraction (SF) by flow cytometry (FCM) on paraffin embedded tumour tissue. The distribution of DNA ploidy is not different from the distribution described for breast cancers in general. No difference is found between the subgroups of medullary and non-medullary cancer when using a new simplified histopathological definition of medullary carcinoma of the breast, recently proposed by us. When using the definition proposed by Ridolfi et al. in 1977, we find significantly more tumours with aneuploidy and high SF in the groups of typical medullary carcinoma (TMC) and atypical medullary carcinoma (AMC) than in the small group of non-medullary carcinoma (NMC), which seems a paradox, as patients with NMC have the worst prognosis. However, the number of patients in the NMC group is very small, and the percentage of aneuploid tumours is very low. In 84 protocolled patients we found no statistically prognostic importance of ploidy or SF, either in the whole group assessed or when stratifying for the histopathological subgroups. However, a prognostic influence of SF can be traced for the non-medullary cancers, according to the new definition, but not for the medullary cancers of the breast. The result emphasizes the impression of MC as being biologically different from other histological types of breast cancer.

DNA Cytometry Consensus Conference. Consensus review of the clinical utility of DNA cytometry in carcinoma of the breast

This is the consensus statement regarding the clinical utility of DNA cytometry in breast cancer from the DNA Cytometry Consensus Conference held in Prout's Neck, Maine, USA, on October 1-4, 1992. Guidelines for clinical DNA cytometry generated at that meeting also appear in this issue of Breast Cancer Research and Treatment.

DNA flow cytometry and pathologic grading as prognostic guides in axillary lymph node-negative breast cancer

BACKGROUND

The recurrence or mortality rate of axillary lymph node-negative invasive breast cancer has been associated with the tumor S-phase fraction, which is measured by DNA flow cytometry. Because many of the studies that established this association were performed using frozen, pulverized tumor specimens, this association could not be tested for independence from the established prognostic factors of histologic and nuclear grading.

METHODS

Histologic, nuclear, and mitotic grades, DNA ploidy, and S-phase fraction (SPF) were determined from paraffin-embedded tumors obtained from 280 women with node-negative invasive ductal carcinomas using standard grading schemes and flow cytometric techniques. These variables were compared with disease-free and cancer-specific survival (CSS) in univariate and multivariate analyses of these patients.

RESULTS

Tumor diameter, SPF, histologic grade, and nuclear grade were significant predictors of disease-free survival (DFS); diameter and SPF had significant associations with CSS. Cox analysis showed histologic grade to be the only independent predictor of relapse, whereas diameter and SPF were independent predictors of mortality. The patients with low nuclear or histologic grade tumors had only a 5% risk of recurrence at 5 years. In contrast, 36% of patients in this series with medium-grade or high-grade high SPF tumors had a 30% risk of recurrence over the same interval.

CONCLUSIONS

Histopathologic grading and flow cytometric determination of SPF appear to provide additive prognostic information for patients with early invasive ductal carcinomas of the breast.

Aneuploidy fraction but not DNA index is important for the prognosis of patients with stage I and II breast cancer--10-year results

BACKGROUND

Individual assessment of the prognosis of patients with breast cancer is crucial for the selection of risk-adapted adjuvant therapy and in follow-up. Parameters from DNA flow-cytometry have been shown to provide significant prognostic information, but published results are in conflict and there are only a few investigations with long-term follow-up. The aim of this study is to clarify the impact of tumor DNA data on the clinical course of stage I and stage II breast cancer patients.

PATIENTS AND METHODS

Several flow-cytometry DNA analyses were performed on tumor samples derived from 191 breast cancer patients entered in a controlled clinical trial after a median follow-up of more than 10 years. In addition to DNA index (DNI) and the percentage of cells in S phase (SPF), an index, designated aneuploidy fraction (AF), was determined. It ascertains the percentage of aneuploid cells out of all cells in the DNA flow-cytometry histogram, and its reproducibility has been tested by measurements of AF in two different samples of the same tumor. Univariate analyses and, in the 122 patients for whom complete information was available, a Cox model, were performed to investigate the individual prognostic impact of flow-cytometry parameters compared with established clinical factors.

RESULTS

AF proved to be a very valuable prognostic indicator both in univariate and multivariate analyses, whereas DNI and SPF failed to provide independent prognostic information. The combination of AF and lymph node status clearly identifies different prognostic subgroups in operable breast cancer.

CONCLUSIONS

Routine evaluation of patients with breast cancer should include tumor DNA flow-cytometry. Aneuploidy fraction is a valuable tool in assessing an individual patient's prognosis and thus can help in the choice of the appropriate adjuvant treatment strategy. Whether it, rather than DNI and SPF should be used, as we found, needs to be validated in a larger prospective investigation.

Nuclear DNA content of human breast carcinoma: a comparison of results obtained by microspectrophotometry and flow cytometry of paraffin embedded tissue

This study compares 2 techniques for estimating the nuclear DNA content of tumor cell lines: (i) static cytometry of smears taken from fresh tissue and (ii) flow cytometry of cells extracted from paraffin embedded tissue. Parallel determinations of DNA content, using both techniques, were made on samples of tissue taken from 130 female patients with breast carcinoma. Using a simple classification into diploid and non-diploid groups, the 2 techniques yielded discrepant results in 11% of cases. The most frequent causes of disagreement were (a) the inability of static cytometry to distinguish between a diploid and a near-diploid peak and (b) for flow cytometry, the difficulty of determining whether a minor peak in the tetraploid region represented the G2 peak of a diploid cell line or the G0/G1 peak of a tetraploid cell line. If it is deemed necessary to accurately assess ploidy status, flow cytometry on paraffin embedded tissue, using modern statistical programmes, would seem to be most practical for routine use, but some neoplasms, particularly those with an equivocal ploidy peak in the tetraploid range by this method, will require static cytometry to accurately assess nuclear DNA content. Using this approach, it appears that the disagreement between the 2 techniques would be less than 5%.

Flow cytometric DNA analysis as prognostic factor in human breast carcinoma

Fresh tumour tissue from 198 primary invasive breast carcinomas was analysed by DNA flow cytometry. 108 tumours were non-diploid. A significantly higher proportion of non-diploid tumours was found among node-positive patients, patients with oestrogen receptor negative tumours and among patients with ductal carcinomas. The survival of patients with diploid and non-diploid tumours was not significantly different (p = 0.1). Totally, 145 tumours were analyzed with respect to S-phase fraction (SPF). The distribution of SPF was different in diploid and non-diploid tumours. A low SPF group, defined as the lower SPF quartile (< or = 4.6% in diploid and < or = 8.5% in non-diploid tumours), was associated with highly differentiated tumours and oestrogen receptor positive tumours. Histological grading revealed a highly significant correlation to SPF. 57% of ductal carcinomas grade I (8 out of 14), 30% of ductal carcinomas grade II (20 out of 67) and 5% of ductal carcinomas grade III (2 out of 37) had a low SPF. Patients within the low SPF group had a significantly longer survival than had patients within the high SPF group (p = 0.006). In a multivariate analysis the SPF was found to be an additional prognostic factor next to node status and ER status.

High levels of DNA index heterogeneity in advanced breast carcinomas. Evidence for DNA ploidy differences between lymphatic and hematogenous metastases

BACKGROUND

The aim of this study was to investigate DNA ploidy status and DNA index heterogeneity of lymphatic and hematogenous metastases of advanced breast carcinomas and the relations among the various tumor sites.

METHODS

DNA ploidy status was analyzed by flow cytometry on frozen and paraffin-embedded tissue blocks taken from primary and metastatic tumor sites in 18 patients with advanced breast cancer.

RESULTS

Presumably because of the extensive sampling, high percentages of DNA aneuploidy, DNA multiploidy, and DNA index heterogeneity were found in primary breast carcinomas as well as in lymph node and distant metastases. DNA aneuploid tumor stemlines were frequently accompanied by DNA diploid tumor stemlines. Most of the DNA tumor stemlines found in the primary tumors recurred in lymph node (55%) and distant (59%) metastases, even after 17 years of relapse-free survival. DNA tumor stemlines found in distant metastases, however, often differed from those in lymph node metastases (61%).

CONCLUSIONS

A marked DNA index heterogeneity can be found in primary and metastatic tumor sites when appropriate sampling is applied. There were no DNA ploidy subclasses, notably absent in either type of metastasis, indicating similar metastatic capacities of both DNA aneuploid and DNA diploid tumor stemlines in advanced breast carcinomas. The difference in DNA ploidy status between lymphatic and hematogenous metastases suggest that these metastases can be generated independently.

Prognostic factors in canine mammary tumors: a multivariate study of 202 consecutive cases

The prognostic variables of 223 consecutively sampled spontaneous mammary tumors from female dogs were studied. These variables included flow cytometric DNA analysis and cell proliferation measured as cells in S-phase rate evaluated from DNA histograms. The dogs were surgically treated, in most cases with unilateral mastectomy (all mammary glands), and 202 of the 223 dogs were studied temporally following surgery. Univariate analysis with correction for age indicated that the variables of lymph node metastasis, elevated S-phase rate, presence of a sarcoma, DNA aneuploidy, and ulceration and infiltrative growth into underlying tissue had a statistically significant negative influence on the survival rates of dogs with a diagnosed malignant tumor. Similar results were obtained from tests on all dogs, but tumor size and its relative hazard increased with increasing size of the tumors, regardless of whether total or disease-specific mortality was considered. Using multivariate-analysis conducted Cox's proportional hazards model, elevated S-phase rate, increased age, and presence of a sarcoma remained statistically significant risk factors. The prognostic value of DNA ploidy and lymph node status varied depending on choice of end point. The study of tumor growth pattern and tumor size provided no prognostic information in the multivariate analysis. Flow cytometric cell analysis, including S-phase rate and DNA ploidy, is of value in predicting the prognosis of canine mammary tumors and can be used as a new prognostic tool to improve the preoperative diagnostics of canine mammary tumors.

Markers of prognosis in breast cancer--the relationship between binding of the lectin HPA and histological grade, SPF, and ploidy

Abnormal cellular glycosylation as demonstrated by the binding of a lectin from Helix pomatia (HPA) to paraffin-embedded sections has been shown in several studies to be associated with aggressive biological behaviour and poor long-term patient prognosis in breast cancer. This study aims to address the possibility that expression of the HPA binding ligand may be of prognostic significance through an association with increased cellular proliferation (as measured by S-phase fraction and histological grade), anaplasia (reflected in histological grade), or ploidy (DNA index). In a 24 year retrospective study, paraffin-embedded sections of 366 primary breast cancers were stained for binding of HPA. All tumours were assessed for histological grade. Flow cytometry was performed on all cases for which sufficient tumour tissue was available (358/366 cases) and S-phase fraction (SPF) and ploidy calculated. Data regarding patient age at diagnosis, nodal status, and tumour size were also recorded. Life table analyses revealed survival advantage for HPA 'non stainers' in comparison to 'stainers' (p < 0.001); for patients with tumours of low grade vs. high grade (p < 0.001); and for those with tumours of low SPF vs. high SPF (p < 0.001). No survival advantage was shown for those with diploid vs. aneuploid tumours (p = 0.17). No association was apparent between HPA binding and grade, SPF, or ploidy (Chi squared values not significant). This was confirmed by multivariate analysis in which nodal status, tumour size, and SPF were independently predictive of survival. There was no confounding effect of grade, SPF, or ploidy upon the correlation between survival and HPA binding. HPA was, however, not independently predictive owing to its strong association with nodal status. The results of this study suggest that the prognostic significance of altered glycosylation, as detected by HPA binding, is unlikely to be through an association with proliferative rate, degree of anaplasia, or cellular ploidy, but may rather be through a direct association with the presence of nodal metastases.

Effect of DNA ploidy classification on prognosis in breast cancer

A series of 327 breast cancers was analyzed for DNA ploidy by flow cytometry from paraffin-embedded tissue, and the resulting DNA histograms were classified independently by 6 researchers in the field as DNA diploid (Di), aneuploid (An), tetraploid (Te), multiploid (Mu), or technically uninterpretable. The frequency of diploid, aneuploid, tetraploid and multiploid cancers varied from 28 to 41%, 33 to 49%, 8 to 21% and 2 to 6%. According to the scale Di-An-Te-Mu, DNA ploidy was not significantly associated with breast-cancer mortality by 2 classifiers, but if DNA euploid cancers (Di+Te) were tested against non-euploid, or diploid cancers against non-diploid, all classifiers found DNA euploid and diploid cancers to have better prognosis. Mortality associated with diploid or tetraploid cancers decreased with improving histogram quality and increasing uniformity of classification, whereas that associated with aneuploid cancers remained unaltered. Among the cases where all classifiers agreed on ploidy, tetraploid, diploid and aneuploid cancers were associated with 100%, 88% and 68% 5-year survival rates. In this sub-set the S-phase fraction and possibly DNA ploidy were independent prognostic factors, together with histological grade, axillary node status, and primary tumor size.

Breast carcinoma growth rate described by mammographic doubling time and S-phase fraction. Correlations to clinical and histopathologic factors in a screened population

BACKGROUND

In a retrospective study, correlations among mammographic doubling times (DT), clinicopathologic prognostic factors, and cytometric predictors were examined.

METHODS

One hundred fifty-eight patients with the possibility to calculate mammographic tumor DT were selected and the tumors were histologically reexamined and flow cytometric analysis for ploidy and S-phase fraction (SPF) was performed.

RESULTS

The tumors were Stage I in 68%, and 45% were detected by mammographic screening. DT ranged from 0.6 months to an indefinite time (median, 9.0 months). Short DT was significantly correlated to large tumor size (P = 0.01) and advanced pathologic tumor stage (P = 0.016), but there was no correlation between DT and histologic grade. Ploidy analysis indicated that there were 57% aneuploid and 7% tetraploid tumors. There was a significant overrepresentation of euploid tumors among tumors smaller than 10 mm (P = 0.02). Ploidy was correlated to histologic grade (P less than 0.001) and DT (P = 0.009). SPF was calculated in 122 cases. SPF correlated significantly with pathologic stage (P = 0.002), tumor size (P = 0.037), histologic grade (P = 0.001), the presence of axillary lymph node metastases (P = 0.046), DT (P = 0.02), and DNA ploidy (P less than 0.001). Compared with interval carcinoma, screening-detected carcinoma showed favorable characteristics concerning size, stage, DT, ploidy, and SPF but not regarding histologic grade and axillary lymph node metastases.

CONCLUSIONS

DT shows great variations. Factors related to tumor biology (i.e., DT, DNA ploidy, and SPF) are strongly correlated with one another, but they have no correlation with axillary lymph node metastases. Cancer detected by screening is discovered at an early stage and shows favorable characteristics concerning DT, ploidy, and SPF.

The Nottingham Prognostic Index in primary breast cancer

In 1982 we constructed a prognostic index for patients with primary, operable breast cancer. This index was based on a retrospective analysis of 9 factors in 387 patients. Only 3 of the factors (tumour size, stage of disease, and tumour grade) remained significant on multivariate analysis. The index was subsequently validated in a prospective study of 320 patients. We now present the results of applying this prognostic index to all of the first 1,629 patients in our series of operable breast cancer up to the age of 70. We have used the index to define three subsets of patients with different chances of dying from breast cancer: 1) good prognosis, comprising 29% of patients with 80% 15-year survival; 2) moderate prognosis, 54% of patients with 42% 15-year survival; 3) poor prognosis, 17% of patients with 13% 15-year survival. The 15-year survival of an age-matched female population was 83%.

Prognostic significance of DNA ploidy in male breast carcinoma. A retrospective analysis of 32 cases

BACKGROUND

DNA aneuploidy has been prognostically significant in female breast carcinoma of low stage, but its value in male breast carcinoma remains undetermined.

METHODS

Flow cytometric DNA analyses were performed retrospectively on paraffin-embedded tissue from 32 men with breast carcinoma (mean follow-up time, 5.97 years [standard deviation +/- 4.63]; range, 1 to 18 years).

RESULTS

Multivariate discriminant function analysis showed only tumor size less than 2 cm to be independently predictive of better disease-free survival (P less than 0.05). DNA ploidy (aneuploid, 25 patients; diploid, 7 patients) and lymph node status (positive, 22 patients; negative, 10 patients) were not predictive of survival, regardless of tumor size.

CONCLUSIONS

The authors concluded that DNA ploidy may not significantly predict survival in male breast carcinoma.

An image cytometric DNA-analysis in breast neoplasms. Parameters of DNA-aneuploidy and their relationship with conventional prognostic factors

In this prospective study, an image cytometric DNA-analysis was performed in 86 women with breast neoplasms (72 primary invasive carcinomas and 14 benign lesions). Four DNA ploidy parameters were analysed: histogram type (according to AUER classification), DNA-index, tumor cells with DNA content above the 5n limit and DNA malignancy grade (DNA-MG, calculation according to Böcking). Their correlations with well established prognostic factors in breast carcinomas (tumor size, lymph node status, histologic grade, hormone receptor content) were studied. All but one benign lesions were diploid (13/14 cases), whereas the majority of the primary invasive breast carcinomas were aneuploid (58/72 cases). A predominance of carcinomas with a percentage of cells superior or equal to 1% with DNA content above the 5n limit was observed (54 cases out of 58). Most of the aneuploid tumors had a histogram type III or IV (53 cases) or a high DNA-index (50 cases). Of these 58 aneuploid cases, only 26 tumors had a DNA-MG superior to 1. Interestingly, 26 tumors had the 4 criteria of aneuploidy, 19 had 3 and 9 had 2 and only 4 tumors had one parameter. The DNA-MG was significantly related to hormonal receptors (p less than 0.001) and tumor size (p less than 0.01). The histogram types (Auer classification) and the DNA content above the 5n limit were correlated with histologic grade (SBR or SBRM) (p less than 0.02). Concerning the DNA-index no correlation was observed with well established prognostic factors. On the other hand no significant correlation was found between these new biologic variables and lymph node status.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationships of DNA ploidy, S-phase fraction and hormone receptor status to tumor stage in breast cancers detected by population screening. The South-East Sweden Breast Cancer Group

Cellular DNA content was analyzed by flow cytometry and estrogen and progesterone receptors by an immuno-biochemical method (EIA) in a consecutive series of 807 frozen breast-cancer samples. Before the beginning of the study, a mammography screening program had been introduced in the region where the tumors were diagnosed. Forty percent of the tumors were judged as DNA diploid, of which 86% were ER-positive. The proportion of ER-positive tumors among non-diploids was significantly lower, or 73% (p less than 0.001). S-phase fraction (SPF) was estimated in 691 cases (86%), with an overall mean of 8.4%. DNA ploidy as well as ER and PR status were independently related to SPF. Unlike the results obtained in most older series, the biological variables correlated significantly with tumor staging factors such as lymph-node status and tumor size. Patients with nodal involvement, especially those with 4 positive nodes or more, more often had tumors which were receptor-negative, DNA aneuploid and of high S-phase rate. Large tumor size was significantly related to lower frequencies of receptor positivity and strongly related to DNA aneuploidy and high S-phase fraction. Multiple linear regression analysis showed that these relationships were mainly due to the associations of SPF with the other variables. S-phase fraction was the only independent factor predicting nodal status, while DNA ploidy in addition to SPF was associated with tumor size. In fact, DNA ploidy (p less than 0.001), ER and PR status (p less than 0.001, p = 0.002), nodal status (p = 0.04) and tumor size (p less than 0.001) were all independently related to SPF.

Proliferation indices of invasive breast carcinomas after in vivo 5-bromo-2'-deoxyuridine labelling: a flow cytometric study of 75 tumours

In vivo labelling of human breast tumours with 5-bromo-2'-deoxyuridine and analysis of proliferation by multiparameter flow cytometry is a new tool by which the labelling index, S phase duration (TS) and potential doubling time (Tpot) of the tumour can be estimated. Tumour specimens from 75 patients with invasive breast carcinoma were studied. Six tumours could not be analysed, and the TS and Tpot values could not be calculated for a further 18. The median labelling index (n = 69) was 4.2 per cent. The median TS (n = 51) was 8.7 h and the median Tpot (n = 51) was 8.2 days. The median intra-assay coefficient of variation for determination of the labelling index was 0.29 in five tumours. There were no significant differences in the total labelling index, TS or Tpot when patients were stratified according to lymph node status, tumour size, tumour grade or menopausal status.

Aneuploid subpopulations in tumour-invaded lymph nodes from breast cancer patients

Fresh, paired primary tumours and lymph node metastases from breast cancer patients were compared by DNA flow cytometry. Although 65% of primary tumours were aneuploid, the detection of aneuploid peaks in corresponding nodal metastases was rare (only 6 cases out of 25) in single-parameter DNA analysis. Detection of aneuploid subpopulations in lymph nodes was greatly improved in dual-parameter DNA analysis using an anticytokeratin (CK) antibody which allowed ploidy determination on CK+ epithelial cells alone. Examination of 12 lymph nodes for CK+ cells revealed the presence of both diploid and aneuploid tumour cells in tumour invaded nodes. In patients with multiploid primary tumours, a subpopulation of the primary aneuploid cells was dominant in the nodal metastases. This suggests that aneuploidy is an integral property of metastatic cells and that within a primary tumour a subpopulation may have a higher metastatic potential.

DNA signal splitting improves detection and analysis of tetraploid populations

Detection of DNA tetraploid populations requires a high index of suspicion at the time of data acquisition and frequently requires subsequent off-line analysis for confirmation, including evaluation of the hypertetraploid region. To analyze these specimens, the flow cytometer operator must run all specimens with the G0G1 peak in low channels or rerun specimens in which tetraploidy is suspected with a lower photomultiplier tube (PMT) voltage or lower amplifier gain setting. Re-analysis may not be possible in specimens with few cells. A simple modification to the cytometer allows PMT signal splitting with simultaneous processing of the signal by two different amplifiers. This allows simultaneous acquisition of histograms optimized for both the hypotetraploid and hypertetraploid regions.

Cellular effects of tamoxifen in primary breast cancer

We have investigated the effect of tamoxifen on the biological characteristics of the primary tumour in 33 patients with breast cancer. All patients had pre-treatment biopsy of the primary breast cancer and subsequent trucut biopsy of the primary tumour after 1-4 months on tamoxifen therapy. The staining patterns in the primary tumour of each of the tumour antigens 115D8, DF3, NCRC-11, and carcinoembryonic antigen (CEA) were unaffected by tamoxifen therapy: there was 16%-31% change before vs. during tamoxifen therapy, but this did not reach significance for any of the four antigens. Comparison of the pattern of staining between the four antigens showed 115D8, DF3, and NCRC-11 to be similar to each other both before and during tamoxifen therapy. All three antigens were significantly different from the staining pattern shown by CEA before and during therapy. Tumour antigen expression pre-treatment did not correlate with therapeutic response for any of the four antigens. However, NCRC-11 staining during tamoxifen therapy did correlate with response (p = 0.004). There was no significant difference in oestrogen receptor status before and during tamoxifen therapy, both of which correlated with response. DNA ploidy of the tumour before tamoxifen did not correlate with response to therapy, but there was a weak correlation between response and DNA ploidy measured during tamoxifen therapy. In only a minority of tumours (up to 30%) did tamoxifen exert an effect on the biological characteristics studied. Changes in these biological markers were mainly in tumours which responded to tamoxifen, and the changes seen were a tendency to greater expression of differentiation antigens.(ABSTRACT TRUNCATED AT 250 WORDS)

Are DNA flow cytometry measurements providing useful information in the management of the node-negative breast cancer patient?

The appropriate management of the breast cancer patient with early stage disease is a controversial, frustrating issue. If laboratory tests could accurately predict tumor behavior, however, the clinician and patient would be greatly aided in their treatment decisions. Although imperfect, there are several new and significant factors that can be used to predict patient prognosis; the most promising and well studied of these factors are DNA flow cytometry measurements. There are at least two estimates of tumor aggressiveness that we can obtain from DNA flow cytometry: one is an estimate of the tumor DNA content or ploidy and the other is an estimate of the tumor proliferative capacity. These measurements have their greatest clinical impact in the node negative patient predicting for relapse-free survival and overall survival. Estimates of proliferative capacity are independent predictors of patient prognosis. Estimates of DNA content are at times controversial and yet still are helpful in distinguishing prognostic subgroups of proliferative activity and may have additional clinical relevance. This discussion will summarize the data obtained from DNA flow cytometry measurements supporting their use as clinically important markers of prognosis in the node-negative patient.

Interrelations between cellular DNA content, S-phase fraction, hormone receptor status and age in primary breast cancer. A series of 1,342 consecutively detected tumors. South-East Sweden Breast Cancer Group

Estrogen and progesterone receptors were assessed by an immuno-biochemical method and DNA content was analysed by flow cytometry in a consecutive series of 1,342 frozen breast cancer samples. Forty-six percent of the ER-positive tumors were DNA diploid compared to 23% among ER-negative cases. The proportion of ER-/PR- cases was highest among hypertetraploid tumors (45%) and lowest among DNA diploids (13%). While receptor positivity and DNA ploidy were strongly related, no differences in mean receptor levels were detected when comparing DNA diploid and aneuploid cases of receptor positive tumors. In receptor positive tumors ER content--but not PR content--increased with age. S-phase fraction (SPF) was estimated in 1,165 cases (87%) with an overall mean of 8.6%. Tumors with high S-phase levels and DNA hypodiploid tumors were significantly more often found in younger than in older patients. The frequency of DNA hypodiploidy was less than 1% among women older than 75 years, while it was 8% among those aged 40 years or younger. S-phase fraction was inversely related to ER and PR status. However, while mean SPF gradually decreased with increasing levels of PR, no significant difference in S-phase fraction was seen for ER concentrations just above the cut-off level for receptor positivity. Tumors positive for both receptors showed the same pattern of DNA ploidy as ER+/PR- tumors while differences in S-phase fraction were observed between the groups. These results support that PR status better than ER status reflects hormone dependent growth in breast cancer.

Flow cytometric DNA index and S-phase fraction in breast cancer in relation to other prognostic variables and to clinical outcome

One frequently used classification of flow cytometric DNA ploidy status (diploid versus nondiploid) was compared with a division into seven ploidy classes based on DNA index (DI) and number of cell populations (hypodiploid, diploid, near-hyperdiploid, hyperdiploid, tetraploid, hypertetraploid, and multiploid). The latter ploidy classification showed a better correlation with prognosis and other prognostic factors (i.e., lymph node involvement, estrogen and progesterone receptor status, and S-phase fraction). The improvement in correlation was mainly due to the identification of near-hyperdiploid cases (DI 1.00-1.14) which could be combined with the diploid cases to form a group with favourable prognosis. In contrast to cases with a small increase in DNA content (near-hyperdiploid), those with a small decrease of DNA content (hypodiploid) manifested a more aggressive disease. In multivariate analysis, S-phase fraction (SPF) was a more important prognostic factor than both the improved or the conventional ploidy classification.

Identification of subgroups with favorable prognosis in breast cancer

The prognostic significance of 16 factors was investigated in a series of 311 women with unilateral, invasive breast carcinoma without distant metastases (M0) and treated with mastectomy. The series consisted of 93% of such cases diagnosed histologically in the city of Turku, Finland, from 1980 to 1984. Mitotic count, histological and nuclear grades, extent of tumor necrosis, axillary nodal status (pN), tumor size (pT), estrogen and progesterone receptor (PR) contents, and S-phase fraction were the most powerful single factors (p = 0.0001 or less). Axillary node negative cancers with no or only spotty tumor necrosis (92% of all pN0 cases) were associated with a 96% 5-year survival rate corrected for intercurrent causes. Among the axillary node positive cases the combination of high PR content (greater than 60 fmol/mg protein) and a low mitotic count could identify a subgroup with a 96% 5-year corrected survival rate (25% of all pN+ cases). It is concluded that both pN0 and pN+ breast cancer contain identifiable subgroups with greatly different prognosis.

The relationship between lymph node metastases and DNA-ploidy status as prognostic factors in invasive breast cancer

We evaluated the relationship between the regional lymph node metastases and the DNA ploidy status in 207 patients with invasive breast cancer, as well as their prognostic values in estimating the prognosis of breast cancer. A significantly higher incidence of aneuploidy was found in patients with a large T3 or T4 tumor, a positive axillary lymph node status, more than 4 positive axillary lymph nodes or positive internal mammary lymph nodes. In a univariate study, the overall survival was significantly correlated with tumor size, axillary lymph node status, axillary and internal mammary lymph node metastases, and DNA ploidy status. In the multivariate analysis, however, only axillary and internal mammary lymph node metastases were recognized as important independent prognostic factors on survival. In this series, the DNA ploidy status did not appear to be an independent prognostic factor either in the entire series or in negative axillary node patients, since it was closely correlated with the axillary or internal mammary lymph node metastases, and the axillary node negative patients had an extremely favorable prognosis.

One or multiple samplings for flow cytometric DNA analyses in breast cancer-prognostic implications?

Flow cytometric assessments of DNA ploidy status and the S-phase fraction (SPF) have been shown to yield prognostic information in breast cancer. The aim of the present investigation was to elucidate the reproducibility of results with regard to tumor DNA heterogeneity, and to ascertain whether the prognostic value of DNA measurements might be enhanced by analyzing two pieces of a tumor instead of one. Agreement with regard to ploidy status (diploid versus non-diploid) was obtained in 90% of cases (71/79) when two adjacent sections of the tumor were investigated, and in 77% of cases (10/13) when four biopsies from different quadrants of the tumor specimen were investigated. The corresponding figures for agreement in SPF (divided into three categories, less than 7.0%, 7.0-11.9%, and greater than or equal to 12%) were 75% (59/79; 2-sample series) and 55% (7/13; 4-biopsy series). The main reason for variance in ploidy results was the difficulties in distinguishing near diploid cell populations. Discrepancies in SPF categories could be explained by minor fluctuations in SPF values near the cut-off levels, or by variance in ploidy status, the fraction of non-diploid nuclei, and background noise due to cell debris. There was a stepwise increase in recurrence rate (RR) among patients with increasing SPF category (RR: 20%, 41%, and 53%). Patients whose SPF categories varied, from low or intermediate in one part of the tumor to high in another, seemed to have a poor prognosis (RR = 57%).(ABSTRACT TRUNCATED AT 250 WORDS)

Image cytometric DNA analysis in human breast cancer analysis may add prognostic information in diploid cases with low S-phase fraction by flow cytometry

Measurements of DNA ploidy can be performed either with image cytometry (ICM) or flow cytometry (FCM); both methods provide independent prognostic information in primary breast cancer. The aim of the present investigation was to compare the two methods and to relate the findings to prognosis (median follow-up 42 months). Concordance in ploidy status (diploid, tetraploid, aneuploid) was obtained in 76% of the samples (168/222). When the fraction of S-phase cells (SPF) from FCM analysis was also taken into consideration, four different groups of samples were obtained (Flow I-IV), which were considered to correspond to the Auer classification (Auer I-IV) of DNA histograms obtained from image cytometry. Complete concordance between the two techniques now was 70% (155/222). Samples classified as Flow I (diploid or near-diploid with low SPF) and Auer I had a distant metastasis rate of 3/60 (5%), as compared to 62/154 (40%) for all other combinations of the Flow and Auer classifications taken together. Thus, the only findings of prognostic importance were that some samples were Flow I but not Auer I, or vice versa. These two groups represent 17 (7.7%) and 14 (6.3%), respectively, of the total number of samples, and had frequencies of distant metastasis similar to those of the other high-risk groups, namely, 7/17 and 5/14, respectively. In a multivariate analysis, flow cytometric S-phase value was a stronger prognostic factor than either the Flow and Auer classification. We conclude that when routine FCM DNA analysis is used, diploid or near-diploid samples with a low S-phase value should be reanalyzed with ICM.

The prognostic significance of ploidy analysis in operable breast cancer

The nuclear DNA content of 98 operable breast cancers was determined by flow cytometric analysis using paraffin-embedded tissue. All patients were on follow-up and failure of treatment or recurrences were identified. DNA ploidy data in the form of ploidy status and DNA index (DI) has been correlated with various clinical and histopathologic factors. The only significant correlation using univariate analysis exists between the histologic grade and DI (P less than 0.025), recurrence of the disease and ploidy status (P less than 0.005), and recurrence of the disease and DI (P less than 0.005). The absence of correlation of ploidy status with other tumor derived factors indicates the independent nature of ploidy as a prognostic factor. Multivariate analysis showed that in the whole-group ploidy (P less than 0.01), tumor margin (P less than 0.01), and menopausal status (P less than 0.01) were significant factors in the order mentioned. DI with a cut of at 1.29 is not found to be a significant factor in the multivariate analysis. The maximum prognostic value of ploidy status was observed in the postmenopausal group (P less than 0.0005). In the node-negative group ploidy status (P less than 0.05) is the only independent significant factor predicting for early relapse. It is concluded that ploidy status is an independent prognostic factor predicting for recurrence of the disease. In the node-negative subgroup this could be used to identify the subset of patients who may benefit from adjuvant treatment.

Pathological prognostic factors in breast cancer. I. The value of histological grade in breast cancer: experience from a large study with long-term follow-up

Morphological assessment of the degree of differentiation has been shown in numerous studies to provide useful prognostic information in breast cancer, but until recently histological grading has not been accepted as a routine procedure, mainly because of perceived problems with reproducibility and consistency. In the Nottingham/Tenovus Primary Breast Cancer Study the most commonly used method, described by Bloom & Richardson, has been modified in order to make the criteria more objective. The revised technique involves semiquantitative evaluation of three morphological features--the percentage of tubule formation, the degree of nuclear pleomorphism and an accurate mitotic count using a defined field area. A numerical scoring system is used and the overall grade is derived from a summation of individual scores for the three variables: three grades of differentiation are used. Since 1973, over 2200 patients with primary operable breast cancer have been entered into a study of multiple prognostic factors. Histological grade, assessed in 1831 patients, shows a very strong correlation with prognosis; patients with grade I tumours have a significantly better survival than those with grade II and III tumours (P less than 0.0001). These results demonstrate that this method for histological grading provides important prognostic information and, if the grading protocol is followed consistently, reproducible results can be obtained. Histological grade forms part of the multifactorial Nottingham prognostic index, together with tumour size and lymph node stage, which is used to stratify individual patients for appropriate therapy.