Significance of S-phase fraction and hormone receptor content in the management of young breast cancer patients

Proliferative markers as prognostic and predictive tools in early breast cancer: where are we now?

In the last few decades, proliferative markers have been broadly evaluated as prognostic and predictive factors for early stage breast cancer patients. Several papers evaluating one or more markers have been published, often with contradictory results. As a consequence, there is still uncertainty about the role of these proliferative markers. The present paper critically reviews the current knowledge about the following markers: thymidine labeling index, S phase fraction/flow cytometry, Ki 67, thymidine kinase (TK), cyclins E, cyclin D, the cyclin inhibitors p27 and p21, and topoisomerase IIalpha. For each marker, the prognostic and predictive role was separately analyzed. Only papers published in English in peer-reviewed journals before June 2004 that include at least 100 evaluable patients were selected. In addition, the prognostic and predictive role of the proliferative markers had to be assessed through multivariate analyses. One hundred and thirty-two papers fulfilled these criteria and 159 516 patients were analyzed. Unfortunately, several methodological problems in the research to date prevent us from including any one of these proliferative markers among the standard prognostic and predictive factors. Early incorporation of translational research and new technologies with clinical trials are needed to prospectively validate biological markers and allow their use in clinical practice.

Flow cytometry in primary breast carcinomas: Prognostic impact of S-phase fraction according to different analysis patterns

BACKGROUND

The aim of the present work was to study the prognostic impact of ploidy and S-phase fraction (SPF) assessed according to recently described methods. These methods of analysis combine different ploidy groups and separate euploid (good) prognostic groups from noneuploid (bad) prognostic groups. The definition of euploidy varied according to the author; some of them even included aneuploid peaks with few events. A comparison was also drawn to the average SPF and the diploid peak SPF observed in aneuploid histograms.

METHODS

From January 3, 1990 to January 7, 1999, 1,984 previously untreated, invasive breast carcinoma samples were snap-frozen and processed for FCM. The present study evaluated all nondiploid and nonmultiploid histograms, using different analysis patterns and the values of the average SPF and diploid SPF.

RESULTS

SPF is a salient prognostic factor even after multivariate analysis for DFS and MFS. Using several methods of analysis of ploidy and SPF shows that the classical method of analysis involving separation of ploidy according to diploidy versus aneuploidy and analysis of SPF restricted to the aneuploid peak in nondiploid and nonmultiploid histograms is as relevant as other recently proposed patterns of analysis, and that the average SPF or the diploid SPF of aneuploid tumors does not add significant prognostic information.

CONCLUSIONS

SPF is a valuable predictor of survival and can be confidently assessed in a simple way by restricting the analysis to the peak of interest (except for multiploid tumors).

Proliferative activity in primary breast carcinomas is a salient prognostic factor

BACKGROUND

The goal of the current study was to investigate the prognostic impact of proliferative activity, together with the other classic clinicopathologic prognostic factors (tumor size, tumor grade, receptor status, ploidy, and lymph node status), in breast carcinoma by counting mitoses and evaluating S phase fraction (SPF) in fresh and frozen tumor samples.

METHODS

From March 1, 1990, to July 1, 1999, a total of 1984 previously untreated invasive breast carcinoma samples were snap-frozen for flow cytometry.

RESULTS

After multivariate analysis incorporating all classic prognostic factors, SPF combined with mitotic activity (i.e., proliferative activity) remained the sole prognostic factor in the lymph node-negative group; proliferative activity was accompanied by tumor size as a prognostic factor in patients with lymph node-positive disease and by lymph node status, lymphatic invasion, and receptor status in the overall population. The predictive value of proliferative activity was superior to that of the reference standards (classic prognostic predictors according to the guidelines of our institution [common oncology practice] and the St. Gallen classification). A review of the literature, focusing on series in which fresh material was used, allowed us to demonstrate that there is widespread agreement regarding the correlation between SPF and prognosis, even after multivariate analysis.

CONCLUSIONS

S phase fraction is a valuable predictor of survival and can confidently be assessed in approximately 80% of cases. In conjunction with mitotic activity, SPF should become a prognostic factor that is used in daily practice by oncologists for the management of breast carcinoma.

Flow cytometry in primary breast carcinomas: prognostic impact of multiploidy and hypoploidy

BACKGROUND

The aims of the present work were to study the prognostic impact of multiploidy and/or hypoploidy in breast cancers and their relation to other classic clinicopathologic prognostic factors (T, grade, receptors, and lymph node status).

METHODS

From 3 January 1990 to 7 January 1999, 1984 previously untreated, invasive breast carcinoma samples were snap frozen for flow-cytometry.

RESULTS

Multiploid tumors had the same prognosis as the aneuploid ones, and those with one hypoploid peak had a better prognosis than did the other aneuploid tumors. However, the presence of both multiploid and hypoploid peaks was correlated with a poor outcome, even after multivariate analysis. In this series after quality control, 93.4% of the histograms could be evaluated concerning ploidy; of these 81.6% could be assessed concerning S-phase fraction (SPF) in the entire population and 77.1% in the multiploid population. In the entire population, we performed a multivariate analysis including all relevant prognostic factors remaining after monovariate analysis by using a compound factor (proliferative activity) regrouping SPF and mitotic activity. This analysis showed that lymph node status and proliferative activity correlates with every type of survival, whereas receptor status correlates with all types of survival except recurrence free survival size, correlated with non-metastasis and overall survival. Grade and age correlated only with overall survival and vascular permeations only with disease-free survival.

CONCLUSIONS

SPF is a valuable predictor of survival, can be confidently assessed in multiploid histograms, and thus improves the yield of flow cytometry. When combined with mitotic activity, the prognostic impact of SPF is the same as that of lymph node status. Tumors that are hypoploid and multiploid have a significantly worse prognosis.

Flow cytometry and quantitative immunohistochemical study of cell cycle regulation proteins in invasive breast carcinoma: prognostic significance

BACKGROUND

Between January 11, 1991 and January 8, 1992, 104 patients with previously untreated, invasive, primitive breast carcinoma were admitted to the authors' hospital.

METHODS

For each patient, flow cytometry DNA analyses on frozen samples and on immunohistochemical staining were performed, including Ki-67, cyclin A, p53, and p21(waf1) (p21), with assessment of the percentages of positive nuclei were assessed. Correlations with classic clinicopathologic data and survival (overall, metastasis free, or recurrence free) and a multivariate analysis were performed.

RESULTS

After a multivariate analysis according to a Cox model that was stratified by age, tumor size, tumor grade, lymph node status, and receptor status, among the factors studied, the presence of p21 was the unique remaining prognostic factor for patients with invasive breast carcinoma. Because of the lack of a correlation between p21 and proliferative factors (Ki-67, S-phase, and cyclin A), the authors combined p21 with those markers and found that, for the different combinations, after statistical analysis, only p21 combined with S-phase or with cyclin A and lymph node status were salient survival prognostic factors.

CONCLUSIONS

Immunohistochemical study of proteins involved in the cell cycle and assessment of proliferative activity using flow cytometric DNA analysis aided the authors in singling out correlations of cyclin A and S-phase, along with p21, with metastasis free survival and overall survival in patients with invasive breast carcinoma. These promising results will require confirmation in a larger series of patients.

[Temporary dependency of steroid-receptor prognostic value in breast cancer]

BACKGROUND

The influence of prognostic factors in breast cancer may change during follow-up. Our aim was therefore to look for time-related changes in hazard ratios for steroid receptor status and the risk of relapse.

PATIENTS AND METHOD

We studied 455 patients with operable primary breast cancer during a mean follow-up period of 72 months (range, 42-130 months). Clinical and histological characteristics were assessed and estrogen receptor (ER) and progesterone receptor (PgR) status were determined and compared to disease-free survival (DFS) and overall survival (OS). Analysis of DFS included fitting a multivariate Cox proportional hazards model, testing for non-proportionality, and examining diagnostic plots.

RESULTS

A total of 66.8% of the tumors were ER positive and 54.7% PgR positive. Receptor status is highly associated with menopausal status, histological grade, peritumoral lymphatic or blood vessel invasion and mitotic index. No correlation was found between steroid receptor status and tumor size, node status or tumor stage. In univariate analysis, ER/PR vs ER+/PR+ display a hazard ratio of 2.15 (IC del 95%, 1.59-2.99) for DFS (p = 0.001) and 1.95 (IC del 95%, 1.38-2.59) for OS (p = 0.0043). In multivariate analysis, steroid receptor status, node status and mitotic index were independent prognostic factors for DFS and OS. By using Cox regression time-dependent covariates model, we show that the steroid receptor status hazard ratio is 5.6 at diagnosis, decreases after 4 years, and loses its significance after 10 years of follow-up.

CONCLUSION

In patients with breast cancer the status steroid receptor have a relatively limited prognostic value and is lost within the first years.

Flow cytometry in primary breast carcinomas. Prognostic impact of proliferative activity

From 1990 to 1996, 607 previously untreated, node-negative, invasive breast carcinomas were sampled by a pathologist for flow-cytometric DNA analysis. The aim of the present work was to study the correlations between flow cytometric results obtained thanks to the American Consensus (AC) guidelines of 1993 and the established clinico-pathological prognostic factors (T, grade, receptors), and despite a short global follow-up (mean of 4 years), to correlate flow cytometry with the outcome of the patients. In this study S-phase fraction (SPF) correlated strongly with tumor size, histological grade, lack of steroid receptors, histological type and was together with the mitotic activity a paramount prognostic factor even after multivariate analysis. This study compared also the technical criteria proposed by the AC with our own more stringent ones and concluded that the criteria of the AC are relevant and allow, thanks to the use of tertiles in the reporting of SPF values, a comparison of values obtained by different teams. Our review of the literature, focused on series using fresh material, enabled us to show that there is a rather wide agreement concerning the relationship between SPF and prognosis most often after multivariate analysis. This despite the lack of standardization in the design of the studies (implementation of the technical steps or reporting of results). When estimated from fresh or frozen material following AC's guidelines. SPF along with mitotic activity should become a prognostic factor used in the daily practice by oncologists in the management of breast carcinomas.

Indicators of loco-regional recurrence in breast cancer. The South East Swedish Breast Cancer Group

AIM

The aim of the investigation was to contribute to the identification of patients who have increased or decreased risk of loco-regional recurrence.

METHODS

Six hundred and twenty-nine consecutive patients with primary breast cancer diagnosed between 1988 and 1990 were studied. Two-thirds of the patients underwent mastectomy. Radiotherapy was administered if patients were node positive or breast conserved. The Nottingham histological grading protocol was used and presence of lymphovascular invasion was assessed. Investigated parameters were: age, size, grade, steroid receptor content, surgical radicality, vascular invasion and nodal status. Statistically significant risk factors for loco-regional recurrence using univariate or Cox proportional hazard analysis were grade and lymphovascular invasion.

RESULTS

Women with grade 1-2, node-negative tumours without vascular invasion had a very low loco-regional recurrence rate-3.1%. Seventeen percent of patients with grade 3 tumours and vessel invasion had loco-regional recurrence.

CONCLUSIONS

Our findings, and those of others, indicate that the use of adjuvant radiotherapy should be influenced to a greater extent by grade and lymphovascular invasion.

Results of two or five years of adjuvant tamoxifen correlated to steroid receptor and S-phase levels. South Sweden Breast Cancer Group, and South-East Sweden Breast Cancer Group

A Swedish cooperative trial demonstrated that 5 years of adjuvant tamoxifen was more beneficial than 2 years of tamoxifen in the treatment of postmenopausal women with estrogen receptor (ER) positive, early stage, invasive breast cancer. The main aim of the present study was to investigate the importance of progesterone receptor (PgR) and ER concentration levels for patients participating in the trial and still distant recurrence free two years after the primary operation. Subgroup analyses revealed that only patients with ER positive and PgR positive breast cancer had improved distant recurrence free survival (DRFS) by prolonged tamoxifen therapy (p = 0.0016). Patients with ER negative and PgR negative as well as ER positive and PgR negative tumors showed no significant effect of prolonged tamoxifen (p = 0.53 and p = 0.80, respectively). The percentage of ER negative and PgR positive breast cancers was too small (2.2%) for any meaningful subgroup analysis. There was a significant positive trend that the concentration level of PgR (high positive vs. low positive vs. negative) decreased the recurrence rate for those with prolonged therapy. No corresponding pattern was found for the ER content. S-phase fraction did not correlate to the recurrence rate of PgR positive breast cancers. Patients recurring during tamoxifen therapy had receptor negative tumors to a greater extent than those recurring after tamoxifen treatment. In conclusion, prolonged tamoxifen therapy for 5 years instead of 2 years was found to be beneficial for patients with ER positive and PgR positive breast cancer, whereas three extra years of tamoxifen had little or no effect for patients with ER positive but PgR negative tumors as well as for steroid receptor negative patients.

S-phase fraction and breast cancer--a decade of experience

During the past decade, more than 300 articles, abstracts, and book chapters have been published about S-phase fraction (SPF) determined by DNA flow cytometry and its clinical utility for patients with breast cancer. However, the use of SPF for making treatment decisions for breast cancer patients remains controversial. After reviewing 273 published articles, we conclude: 1) Despite different techniques and cutpoints, correlations between SPF and other prognostic markers are relatively consistent across studies; higher SPF is generally associated with worse tumor grade, absence of steroid receptors, larger tumors, and positive axillary lymph nodes. 2) Higher SPF is generally associated with worse disease-free and overall survival in both univariate and multivariate analyses; SPF values from laboratories that have conducted validation studies can be used, in combination with other factors, to estimate the prognosis of patients with primary breast cancer. 3) There is considerable variability among laboratories regarding assay methodology, cell-cycle analysis techniques, and cutpoints for classifying and interpreting SPF; use of SPF values from different laboratories is problematic, and there remains a need for standardization of these processes and well-designed confirmation studies. We conclude that measurement of SPF does have clinical utility for patients with breast cancer, but standardization and quality control must be improved before it can be routinely used in community settings.

Applying the Nottingham Prognostic Index to a Swedish breast cancer population. South East Swedish Breast Cancer Study Group

The aim of this study was to assess the applicability of histopathological grading according to the protocol of Elston/Ellis and the Nottingham Prognostic Index (NPI) to a defined breast cancer population. The NPI is the sum of the individual scores concerning grade, tumour size, and lymph node status, each weighted according to regression coefficients of a Cox proportional hazard analysis and calculated for each individual breast cancer patient. 630 consecutive patients with invasive breast cancer diagnosed 1988-91 were retrospectively followed up and their tumours reviewed and graded. A Cox proportional hazard analysis was performed. Grade, lymph node status, and tumour size were statistically significant predictors of survival within the follow up period (median 7.2 years). Similar to NPI, a temporary index (Kalmar Prognostic Index, KPI) was derived and normalised to NPI for comparison (KPI(norm)). NPI and KPI(norm) gave similar prognostic power in spite of the differences of the patient populations from which the 2 indices were derived. Patients with NPI 4 or less had 0.66% breast cancer specific mortality during the follow up time. 14% of the patients with NPI 4.1-5 and 32% of those with an index sum 5.1-6 died from breast cancer during this time. Younger patients tended to have higher grade tumours. We advocate the common use of grade and the NPI in order to increase the comparability of groups of patients receiving different therapies.

Prognostic value of steroid receptors after long-term follow-up of 2257 operable breast cancers

The prognostic value of oestrogen receptor (ER) and progesterone receptor (PR) was estimated through a multicentric study of 2257 operable breast cancer patients followed up for a median of 8.5 years. None of the patients had received adjuvant therapy. The series included 33.3% stage I patients, 57.1% stage II, 5.7% stage IIIa and 2.4% stage IIIb. At the end point of the study 589 metastases and 537 deaths from cancer were recorded. Receptor measurements were performed by radiolgand assay according to a uniform protocol. A total of 68.8% of the tumous were ER positive and 54.0% PR positive ( > or = 10 fmol mg-1 cytosol protein). In univariate analysis, ER and PR status (positive/negative) were of prognostic value (P < 0.001) for the disease-free interval (DFI), the metastases-free interval (MFI) and the overall survival (OS). The OS of the patients after a first metastasis was also significantly different between ER-positive and -negative tumours (P < 0.001). In multivariate analysis (Cox proportional hazard model, 1665 patients), only the ER status showed a significant difference (P < 0.01) between positive and negative groups regarding the DFI, MFI and OS. By using Cox non-proportional, time-dependent models, we show that the predictive value of ER status of the primary tumour decreases by approximately 20% per year, losing its significance after 8 years of follow-up. Overall, when compared with TNM and histological grading, ER and PR status have a low prognostic value, their major interest remaining solely in the domain of therapeutic decision.

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.

Improved detection of DNA aneuploidy in primary breast cancer using quantitative DNA image analysis in combination with fluorescent in situ hybridization technique

To obtain more information about the relationship between numerical aberrations of chromosome 1 and the overall DNA content of breast cancer cells, fluorescent in situ hybridization with a pericentromeric probe for this chromosome and image analysis based densitometry were carried out on imprints of benign (15 cases, mainly fibroadenomas) and malignant breast disease (31 invasive ductal carcinomas out of 45 cases). The most pronounced aneuploidy was observed in invasive ductal and lobular carcinoma cases both by in situ hybridization and DNA content (76.7 and 75.0% were aneuploid). The frequency of cells with two spots for chromosome 1 was 48.3 and 51.5%, respectively, as compared to 80.3% in control lymphocytes. There was a weak overall correlation (r2 = 0.83) between DNA content and copy number of chromosome 1 in the malignant samples, although some of the DNA diploid/near diploid carcinomas showed a marked aneusomy for this chromosome. Also, some aberrations were present in the benign breast disease samples. Classification of cases by a linear discriminant analysis was most accurate when both techniques were combined (77% of cases correctly classified, according to anatomo-pathological diagnosis). The variables which received the highest weight in the linear discriminant function are the percentage DNA-diploid cells and the fraction of cells with two spots for chromosome 1. The sensitivity and sources of error of both techniques is considered.

S-phase fraction and survival benefit from adjuvant chemotherapy or radiotherapy of breast cancer

Cancer chemotherapy interacts with cell proliferation, but data on the relationship between cancer cell replication and the effect of adjuvant chemotherapy are scarce. We have investigated the S-phase fractions of the primary tumour from premenopausal breast cancer patients who participated in a randomised trial comparing 12 cycles of polychemotherapy (CMF) with post-operative radiotherapy. DNA flow cytometry was performed on frozen tissues from 208 primary breast carcinomas, of which the S-phase fraction was estimated in 176 cases. There was a significantly higher benefit from CMF among patients with a high S-phase fraction (P = 0.0033). The relative risk of distant recurrence or death in the chemotherapy group as compared with the radiotherapy group was 0.19 for patients whose tumours had an S-phase fraction of 10% or over (95% CI 0.07-0.51) and 1.55 (0.88-2.73) for patients whose tumours showed lower S-phase levels. The interaction was still significant in multivariate analysis (P = 0.0057), including lymph node metastases, tumour size and oestrogen receptor content. We conclude that the benefit from adjuvant chemotherapy compared with radiotherapy is largely confined to patients with highly proliferative tumours.

Aneuploidy for chromosome 1 and overall DNA content in benign and malignant breast disease

Fluorescence in situ hybridization (FISH) with a probe for the pericentromeric region of chromosome 1 and DNA content measurements by image-analysis-based densitometry have been carried out on imprints of benign and malignant breast tissue. In general, an increase in the number of spots per nucleus was observed in the invasive carcinomas, with a large intercellular variation. In comparison with lymphocytes from controls, some cases of benign breast disease already had an increased frequency of aneusomy of chromosome 1, although they were all (near)diploid by DNA-content. However, an overall concordance between the DNA content measurements and the results of FISH was observed, although some exceptions were seen. A statistically significant correlation between the DNA index and the mean number of spots for chromosome 1 per nucleus was found. A linear discriminant analysis was applied on the data; the resulting classification of patients was most accurate when parameters describing DNA content and FISH results were combined.

Relationship of DNA ploidy and S-phase fraction to survival after first recurrence of breast cancer

Flow cytometry was performed on frozen specimens from the primary tumour of 184 women with recurrent breast cancer. No significant association was seen between DNA ploidy and the other prognostic factors investigated. Patients with a high S-phase fraction had more often a negative estrogen receptor (ER) status and a short disease-free interval. A shorter survival after disease recurrence was seen both in patients with DNA aneuploid tumours and among those with a high S-phase fraction. Patients with DNA tetraploid tumours showed the longest survival after recurrence. In this subgroup, half of the patients survived more than 3 years after recurrence and the estimated survival rate at 10 years was 17%. In a Cox's regression analysis including 116 patients, site of recurrence, number of positive nodes at time of primary operation, size and ER content of the primary tumour as well as DNA ploidy showed additional prognostic value.