DNA index, S-phase fraction, histological grade and prognosis in breast cancer

DNA index and S-phase fraction (SPF) were measured by flow cytometry on paraffin embedded tissue from 140 primary breast tumours. The results of DNA analysis were compared with the size, degree of axillary node involvement, histological grade and steroid receptor content of the tumours, as well as with the patients' subsequent clinical course. Forty-four (31.4%) of the 140 tumours were diploid. S-phase fraction was evaluable for 134 (95.7%). The median SPF of the whole population was 7.1%, with diploid tumours having a significantly lower median SPF (3.2%) than aneuploid (10.1%, P less than 0.001). Both aneuploidy (P = 0.002) and high SPF (P less than 0.001) were strongly associated with high histological grade. There was no significant association between either DNA ploidy or SPF and tumour size, nodal status or steroid receptor content. An SPF below the median was strongly associated with better relapse-free survival (P = 0.008), overall survival (P = 0.004) and survival after relapse (P less than 0.001). Ploidy did not correlate significantly with clinical course. Multivariate analysis using the Cox model suggested that, while SPF gave prognostic information independent of tumour size or nodal status, this independent significance was lost when histological grade was included in the analysis.     

The relationship between c-erbB-2 expression, S-phase fraction and prognosis in breast cancer.

The relationship between c-erbB-2 gene expression (assessed immunohistochemically), S-phase fraction (SPF) and prognosis has been analysed in 172 women with primary breast cancer. c-erbB-2 staining was independent of age, tumour size, number of nodes involved, tumour grade and DNA ploidy, but was more common in oestrogen receptor (ER) negative tumours (P = 0.02) and progesterone receptor (PgR) negative tumours (P = 0.03). A weak correlation between c-erbB-2 staining and SPF was observed (r = 0.18). Amongst women with node negative disease, SPF was significantly related to relapse free survival (RFS, P = 0.04) while c-erbB-2 staining was not (P = 0.2). In contrast, both SPF (P = 0.002) and c-erbB-2 staining (P = 0.016) provided significant prognostic information on RFS for women with node positive disease. Multivariate analysis showed that c-erbB-2 staining and SPF gave independent information on RFS for women with node positive disease.     

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

Summary Abnormal cellular glycosylation as demonstrated by the binding of a lectin fromHelix 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.     

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” sub-population defined as DNA index (DI) <0.96 or 1.44 ≤ Dl < 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 differences among 7 different Dl 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 ≤ 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, 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 ≤ 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. © 1994 Wiley-Liss, Inc.     

Tumour DNA ploidy as an independent prognostic factor in breast cancer

We determined nuclear DNA content from 308 archival paraffin-embedded malignant breast tumours and evaluated the survival of the patients by univariate and multivariate statistical analyses. The overall 8-year survival rate of stage I-III breast cancer patients was 74.3% in DNA-diploid and 51.2% in DNA-aneuploid tumours (P less than 0.0001). DNA ploidy had prognostic significance in both node-negative and node-positive breast cancer, primarily in cases with steroid receptor-positive tumours. In a Cox multivariate analysis DNA ploidy (P = 0.001), primary tumour size (P = 0.0007), nodal status (P = 0.04) and the content of progesterone receptors (P = 0.0008) emerged as significant independent prognostic factors, whereas oestrogen receptor status, age and menopausal status of the patients had no significant independent prognostic value. If the histological grade of ductal carcinomas was also included in the Cox model, both grade and DNA ploidy had independent prognostic effect. In conclusion, our results indicate that the analysis of DNA ploidy is a useful adjunct in the assessment of prognosis for breast cancer patients.     

The influence of tumour cell DNA content on survival in colorectal cancer: a detailed analysis

We have investigated the influence of tumour cell DNA content (ploidy) on survival of 416 patients undergoing excisional surgery for colorectal cancer. Two hundred and eleven (51%) tumours had an abnormal DNA content (aneuploid or tetraploid). There was no correlation between ploidy status, sex, age and pathological stage, histological grade, tumour site, local tumour extension or assessment of curability. Patients with tumours with an abnormal DNA content had a poorer survival 68/211 (32%) than patients with near normal (diploid) DNA content 88/205 (43%) (test statistic 5.0, P = 0.02). The patient subgroups in which DNA content exerted an influence on survival were: stage B tumours (P = 0.0058), moderately differentiated tumours (P = 0.004), rectal tumours (P = 0.02), and mobile tumours (P = 0.02). Multivariant analysis showed that pathological stage, local tumour extension and DNA ploidy were all independent prognostic indicators whereas histological grade, tumour site and assessment of 'curability' were not. The influence of pathological stage, however, was much greater than that of local tumor extension or DNA ploidy. Tumour cell DNA content together with pathological stage and local tumour extension may be used in a prognostic index and may be important in planning adjuvant therapy.     

Cell kinetics in human breast cancer: Comparison between the prognostic value of the cytofluorimetric S-phase fraction and that of the antibodies to Ki-67 and PCNA antigens detected by immunocytochemistry

The determination of cell proliferation is one of the more widely used tools for assessing prognosis. However, additional research in this field is warranted because today there are several methodological procedures available for monitoring cell kinetics and it has still not been established which is the most reliable marker of proliferation and which possesses the greatest prognostic value. We performed this study in a series of primary invasive breast cancers to compare the prognostic value of S-phase fraction (SPF) by flow cytometry, the most widely used method for detecting proliferation at present, with that of antibodies to Ki-67 and PC-10 to proliferating-cell nuclear antigen (PCNA) detected by immunocytochemical methods. A significant linear relationship was observed only between SPF and Ki-67. In univariate analysis SPF and Ki-67 values, nodal status, histological grading and peritumoral lymphatic-vessel invasion were significant predictors of relapse-free survival (RFS). As far as overall survival (OS) is concerned, only SPF, Ki-67 and nodal status were significantly associated with the risk of death. PCNA had no prognostic value for either RFS or OS. In multivariate analysis only SPF and nodal status retained a significant and independent prognostic value. Neither the cell-kinetics parameters assessed by immunocytochemistry (i. e. Ki-67 and PCNA) nor histological grading were independent prognosticators. In conclusion, our results provide evidence that the determination of SPF by flow cytometry was the strongest cell-kinetics marker used to assess prognosis in this series of breast cancers. However, different and novel markers of cell kinetics need to be compared in larger series in order to identify the best one. © 1994 Wiley-Liss, Inc.     

DNA flow cytometry, nuclear morphometry, mitotic indices and steroid receptors as independent prognostic factors in female breast cancer.

Clinical features, 8 histological variables, 7 nuclear morphometric variables, 2 mitotic indices, oestrogen-receptor (ER) and progesterone-receptor content (PR), DNA ploidy and S-phase fraction (SPF) were entered in a Cox's model to assess their independent predictive value in 216 breast-cancer patients followed up for over 9 years. In the whole series, histological type (p = 0.007), volume-corrected mitotic index (M/V index) (p = 0.01), axillary-lymph-node (pN) status (p = 0.024) and the year of treatment (p = 0.045) predicted independently the recurrence-free survival (RFS). In a sub-analysis including SPF (n = 148), the year of treatment (p = 0.003), tumour diameter (p = 0.004), SPF (p = 0.022) and nuclear pleomorphism (p = 0.056) independently predicted the RFS. In a Cox's analysis of the whole series, tumour diameter (p less than 0.001), pN status (p = 0.001), PR status (p = 0.002) and the year of treatment (p = 0.021) were independent predictors of survival. In a separate analysis including also SPF (n = 148), tumour diameter (p less than 0.001), SPF (p = 0.003), pN status (p = 0.008) and the year of treatment (p = 0.015) proved to be independent prognostic factors. The results show that tumour diameter, pN status, M/V-index, histological type, SPF and PR status comprise a sufficient combination of prognostic factors in female breast cancer. In pN patients, age and SDPE may be of additional prognostic significance. The prognostic scores combining the independent prognostic variables reflecting both the proliferative rate and metastatic potential of the tumours are accurate predictors of the RFS and overall survival.     

DNA content in high and intermediate grade non-Hodgkin's lymphoma-prognostic significance and clinicopathological correlations

Flow cytometric (FCM) estimation of DNA content has been performed on tumour tissue from 197 patients with high and intermediate grade non-Hodgkin's lymphoma (NHL) to investigate the clinicopathological correlations and prognostic significance of DNA ploidy and proliferative activity. Fifty-one per cent of tumours were diploid; the remaining non-diploid tumours were near diploid (14%), aneuploid (28%) and tetraploid (7%). In 81 tumours multiple analyses were performed from different regions of the tumour, ploidy discrepancy was seen within the same tumour in 13/81 tumours (16%), and intra-tumour variation in proliferative index (PI) in 72 tumours was estimated at +/- 5%. Ploidy status did not correlate with histological subtype (Kiel or Rappaport), Ann Arbor stage or the site of disease at presentation. There was no significant difference in response rate, relapse-free survival (RFS) or overall survival rate between the different ploidy categories. Tumour proliferative index (PI) varied markedly between patients (range 2-51%, median 14%). A significant association was observed between PI and histological subtype in the Kiel classification (P = 0.001). The median PI for the lymphoblastic lymphomas was 20% compared with 10% for the centrocytic tumours. An elevated PI was significantly associated with a reduced rate (P = 0.023), with 71% of patients with a low PI (less than 20%) achieving complete remission (CR) compared with 49% patients with a high PI (greater than 20%). Despite this correlation with CR, PI was not significantly associated with overall survival. When the DNA data was combined with over 20 other potential prognostic factors in multivariate analysis, ploidy and proliferative activity did not prove to be of independent prognostic significance for response, RFS or overall survival. In 20 patients additional biopsy material was available from the site of subsequent relapse. In these cases, although the histology at relapse remained unchanged, ploidy status altered in 13/20 patients, and there was a significant rise in tumour PI at relapse compared with the initial pre treatment biopsy (P = 0.017). We conclude that in high and intermediate grade NHL, DNA ploidy as assessed using conventional FCM analysis is not significantly associated with clinical outcome. However, proliferative activity does correlate with histological subtype and response to therapy, and this parameter warrants further evaluation in future studies.     

DNA aneuploidy and low S-phase fraction as favourable prognostic signs in metastatic melanoma

The prognostic value of cellular DNA content in melanoma metastases was investigated by flow cytometric analysis of fresh or paraffin-embedded tumour blocks from 95 consecutive patients referred to the Helsinki University Central Hospital Melanoma Team. Thirty-three per cent of the tumours were DNA diploid and 67% DNA aneuploid. S-phase fractions were lower in DNA diploid than in DNA aneuploid tumours (10.7% and 17.6%). Tumour ploidy and S-phase fraction were shown by multivariate Cox model analysis to be independent prognostic variables and major determinants of survival after first recurrence. Surprisingly, patients with DNA aneuploid tumours and with tumours with low SPF survived significantly longer than those with DNA diploid or high SPF tumours. This exceptional finding of favourable prognosis for DNA aneuploid tumours was more prominent among patients receiving intensive systemic therapy and among patients with stage IV disease, probably indicating a tendency for DNA aneuploid tumours to have higher sensitivity to systemic therapy.     

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

PURPOSE: To assess the significance of S-phase fraction (SPF) and DNA ploidy evaluated by DNA flow cytometry as prognostic markers in stage I or II breast cancer. PATIENTS AND METHODS: A series of 271 patients, treated by surgery, radiotherapy+/-systemic therapy was analysed (median follow up: 64 months). Standardized flow cytometry cell preparation from frozen samples and consensus rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. Four groups were defined based on combinations of DNA ploidy (DIP: diploid; ANEUP: aneuploid) and SPF: DIP and low SPF (DL, N=37), DIP and medium or high SPF (DMH, N=76), ANEUP and low SPF (AL, N=24), ANEUP and medium or high SPF (AMH, N=68). Local control rate (LCR), disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS) were correlated with DNA ploidy, SPF, DL to AMH groups, T and N stages, SBR grading, age, and hormonal status on univariate and multivariate analysis (Cox model). RESULTS: On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N- patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N- stage I and II breast cancer.     

c-erbB-2 oncoprotein overexpression identifies a subgroup of estrogen receptor positive (ER+) breast cancer patients with poor prognosis

Purpose:To investigate the predictive value of c-erbB-2 oncoprotein expression as compared with established histopathological and cytometric indicators of disease evolution in breast carcinoma. Patients and methods:A short-term retrospective study was conducted on a series of 306 breast cancer patients. Classic prognostic factors included tumour size, nodal involvement, histological grading, and hormone receptor status. Flow cytometric DNA ploidy and S-phase fraction (SPF) were also assessed. A Cox proportional hazards regression model was used for multivariate statistical analysis. Results:c-erbB-2 overexpression was present in 43 out of 295 (14.6%) tumours, and showed a statistically significant correlation with high histological grade, DNA aneuploidy, high SPF and lack of estrogen receptors (ER). Univariate analysis revealed its association with worse disease-free survival (DFS) and overall survival (OS). The combined evaluation of c-erbB-2 with ploidy and SPF defines a variable (P + S + c) that showed a significant correlation with disease outcome. By multivariate analysis, only nodal status (P < 0.001) and P + S + c subgrouping (group 2: P = 0.002; group 3: P = 0.001) in relation to DFS, and nodal status (P = 0.001) and DNA ploidy (P = 0.006) in relation to OS, retained independent prognostic significance. Subset analyses showed that cytometric parameters, P + S + c subgrouping and hormone receptors were significantly correlated with disease outcome in node-positive patients, whereas in node-negative subgroup no prognostic indicators were found. c-erbB-2 overexpression exhibited a trend in node-positive breast cancer (DFS: P = 0.068; OS: P = 0.086), and significant correlation with poor clinical evolution in ER positive patients (DFS: P = 0.015; OS: P = 0.004), mostly receiving tamoxifen. Conclusions:c-erbB-2 is an independent prognostic indicator of DFS when evaluated in conjunction with ploidy and SPF. It also seems to predict response to tamoxifen therapy, by identifying a subgroup of ER positive (ER+) breast cancer patients with poor prognosis.     

Tumour growth rate and DNA flow cytometry parameters as prognostic factors in metastatic melanoma.

The prognostic value of flow cytometric parameters and tumour growth rate of melanoma metastases under the mouse renal capsule was investigated for tumours from 117 consecutive patients referred to the Helsinki University Central Hospital Melanoma Team. DNA flow cytometry (FCM) was interpretable for the tumours of 114 patients, and growth rate analysis for 82 patients, both results being available from 79 patients. Thirty-six percent of the tumours were DNA diploid and 64% DNA aneuploid. Tumour ploidy and S-phase fraction were shown by multivariate Cox model analysis to be independent prognostic variables and major determinants of survival after first recurrence. Patients with DNA diploid or aneuploid tumours survived a median 16 and 27 months, respectively. A high growth rate of tumour sample in vivo under the mouse renal capsule tended to be a sign of poor prognosis, although not reaching statistical significance. Combining the results of FCM, tumour growth rate and TNM stage, we propose a highly efficient prognostic scoring method. Patients with a score above 0.75 had a median survival of 11 months compared to 30 months among patients scoring under 0.75 (P less than 0.0001). This score was the most significant (P less than 0.0001) prognostic factor in the Cox model when TNM stage, age, ploidy, SPF, and tumour growth rate were analysed as covariates.     

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

Purpose. To assess the significance of S-phase fraction (SPF) and DNA ploidy evaluated by DNA flow cytometry as prognostic markers in stage I or II breast cancer.Patients and methods. A series of 271 patients, treated by surgery, radiotherapy ± systemic therapy was analyzed (median follow up: 64 months). Standardized flow cytometry cell preparation from frozen samples and consensus rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. Four groups were defined based on combinations of DNA ploidy (DIP: diploid; ANEUP: aneuploid) and SPF: DIP and low SPF (DL, n=37), DIP and medium or high SPF (DMH, n=76), ANEUP and low SPF (AL, n=24), ANEUP and medium or high SPF (AMH, n=68). Local control rate (LCR), disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS) were correlated with DNA ploidy, SPF, DL to AMH groups, T and N stages, SBR grading, age, and hormonal status on univariate and multivariate analysis (Cox model).Results. On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N(–) patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N(–) stage I and II breast cancer.     

Flow cytometry in comparison with mitotic index in predicting disease outcome in transitional-cell bladder cancer

The DNA content and S-phase fraction were measured by flow cytometry in 448 tumour biopsy specimens from transitional-cell bladder cancer (TCC). The samples were also analyzed for mitotic index, WHO grade and papillary status, and histological and flow cytometric data were then correlated to clinical behaviour of turnours during a mean follow-up period of 9.9 years. TNM classification, WHO grade, papillary status, mitotic index, DNA ploidy and S phase fraction were significantly interrelated. Twenty-four percent of tumours showed heterogeneous DNA indices when measured from multiple samples (measured in 94 cases). Of the histological parameters, independent predictors of progression in superficial tumours were the S-phase fraction and mitotic index. In superficial tumours, S-phase fraction and the mitotic index included all the available independent prognostic information in survival analysis, whereas in muscle-invasive tumours T category was the most important prognostic factor. The results suggest that DNA ploidy has no independent prognostic value in transitional-cell bladder cancer, whereas proliferation indices (SPF, mitotic index) are important prognostic factors. Accordingly, malignancy classification of papillary bladder tumours can be based on proliferation indices alone. Nodular tumours run an unfavourable course and their malignancy grading by flow cytometry or by mitotic index is not relevant.     

Gastric lymphomas in Turkey. Analysis of prognostic factors with special emphasis on flow cytometric DNA content

BACKGROUND: In contrast to DNA ploidy, to the authors' knowledge the prognostic significance of S-phase fraction (SPF) in gastric lymphomas has not been determined. In the current study, the prognostic significance of various parameters including SPF and DNA aneuploidy were analyzed and some distinct epidemiologic and biologic features of gastric lymphomas in Turkey were found. METHODS: A series of 78 gastric lymphoma patients followed at Hacettepe University is reported. DNA flow cytometry was performed for 34 patients. The influence of various parameters on survival was investigated with the log rank test. The Cox proportional hazards model was fitted to identify independent prognostic factors. RESULTS: The median age of the patients was 50 years. There was no correlation between patient age and tumor grade. DNA content analysis revealed 4 of the 34 cases to be aneuploid with DNA index values < 1.0. The mean SPF was 33.5%. In the univariate analysis, surgical resection of the tumor, modified Ann Arbor stage, performance status, response to first-line chemotherapy, lactate dehydrogenase (LDH) level, and SPF were important prognostic factors for disease free survival (DFS). The same parameters, excluding LDH level, were important for determining overall survival (OS). In the multivariate analysis, surgical resection of the tumor, disease stage, performance status, and age were found to be important prognostic factors for OS. CONCLUSIONS: To the authors' knowledge the current study is the first to demonstrate the prognostic significance of SPF in gastric lymphomas. The distinguishing features of Turkish gastric lymphoma patients are 1) DNA indices of aneuploid cases that all are < 1.0, which is a unique feature; 2) a lower percentage of aneuploid cases; 3) a higher SPF; 4) a younger age distribution; and 5) lack of an age-grade correlation. The authors conclude that gastric lymphomas in Turkey have distinct biologic and epidemiologic characteristics.     

DNA ploidy, S-phase fraction and mitotic indices as prognostic predictors of female breast cancer.

DNA ploidy, S-phase fraction (SPF), mitotic index (MI), volume corrected mitotic index (M/V index) and standard prognostic factors were related to disease outcome in a series of 363 women with breast cancer followed-up for over 10 years in our clinic. DNA ploidy and SPF were significantly related to histological type, tumour grade and mitotic indices (p < 0.001). In univariate survival analysis, pN status (p < 0.0001), tumour diameter (p < 0.0001), MI (p = 0.001), M/V index (p = 0.0003) and SPF (p = 0.015) predicted survival. In pN(-) tumours. MI (p = 0.059) was related to survival. In pN(+) tumours, tumour diameter (p = 0.0004), M/V index (p = 0.023) and SPF (p = 0.045) predicted survival. In multivariate survival analysis, tumour diameter (p < 0.001). M/V index (p < 0.007), pN status (p = 0.014) and patient age (p = 0.09) were independently related to survival. In pN(-) tumours, tumour diameter independently predicted survival (p = 0.033). In pN(+) tumours, tumour diameter (p < 0.001), M/V index (p = 0.006) and the year of treatment (p = 0.08) were independent predictors. The results show that tumour diameter, pN status and proliferative activity of cancer cells are important prognostic factors in breast cancer. Of the proliferation indices, M/V index and SPF are equally powerful predictors, and the use of M/V index is advocated due to simplicity of the assessment.     

A comparison between flow cytometric assessment of S-phase fraction and Nottingham histologic grade as prognostic instruments in breast cancer

Flow cytometric DNA analysis with assessment of S-phase fraction and DNA ploidy was compared to Nottingham histologic grade. The study population consisted of 654 patients who presented between 1987 and 1996 with primary operable breast cancer and whose tumours had been analysed for S-phase fraction and DNA ploidy at the time of surgery. Grade, tumour size, node status, steroid receptor status, age, S-phase fraction and DNA ploidy were analysed univariately and multi-variately in a Cox proportional hazard analysis. In the univariate analyses all parameters were statistically significantly associated with breast cancer mortality during the follow-up period of 2–11 years. The most powerful predictor of death from breast cancer in the multiple regression analysis was grade. Patients with grade 1 tumours have excellent prognosis. We conclude that tumour grade is a strong prognostic indicator applicable to all breast cancer patients, regardless of size and nodal status, and advocate its general use.     

Predicting outcome for patients with node negative breast cancer: a comparative study of the value of flow cytometry and cell image analysis for determination of DNA ploidy.

This study was aimed at determining whether tumour DNA content measured by cell image analysis could provide additional prognostic information when compared to that provided by flow cytometry. Sections cut from paraffin blocks of tumours from 101 patients with node negative breast cancer were analysed by both methods and the results related to other prognostic variables and to patient relapse and overall survival. DNA ploidy measured by flow cytometry classified 46 tumours as diploid and 55 as aneuploid, whereas by cell image analysis 30 were diploid and 71 aneuploid (P less than 0.002). There were 20 tumours with discrepancies between the two methods; 18 of these were tumours with only one peak in flow analysis, but determined to be aneuploid with image analysis. DNA content as measured by both methods was significant for predicting relapse and survival by log-rank test, as were tumour histological grade, c-erbB-2 expression and tumour size. Multivariate analysis showed DNA ploidy measured by flow cytometry to be the only variable of independent significance (P less than 0.02) for both relapse and overall survival. Compared with cell image analysis, flow cytometry demonstrated a significantly higher proportion of diploid tumours, which may be related to differences in the internal standards applied to each method. We suggest that cell image analysis techniques can provide more sensitive information on the DNA content of tumour cells by direct measurement of nuclear DNA density of both normal lymphocytes and tumour cells in the same section. However, although image analysis appears to be more sensitive than flow cytometry in detecting DNA aneuploidy, the image technique appears to lack the specificity of flow cytometry in correlation with clinical outcome.