Interobserver concordance of Ki67 labeling index in breast cancer: Japan Breast Cancer Research Group Ki67 Ring Study

The standardized assessment of Ki67 labeling index (LI) is of clinical importance to identify patients with primary breast cancer who could benefit from chemotherapy. In this study, we evaluated the interobserver concordance of Ki67 LI assessment. Six surgical pathologists participated and all the slides were prepared from archival breast cancer tissues fixed in 10% buffered formalin for 24 h and stained with MIB‐1. Three independent studies were conducted. In the first study, 30 stained slides were assessed using two different methods: the scoring system, with a positive rate scored from 1 (0–9%) to 10 (90–100%) by visual estimate; and the counting method, with approximately 1000 cells counted in hot spots. In the second study, 20 tumors with Ki67 LI 5–25% were assessed, and in the third study, 15 printed photographs of stained slides were assessed to avoid variations by selecting different fields. In study 1, the counting system (intraclass correlation coefficient [ICC], 0.66 [95% confidence interval 0.52–0.78]) demonstrated a better correlation than the scoring system (ICC, 0.57 [0.42–0.72]). In study 2, the assessment for Ki67 LI of 5–25% demonstrated a correlation (ICC, 0.68 [0.50–0.81]) similar to that of study 1 (unrestricted range of Ki67 LI). In study 3, the assessment of Ki67 LI by counting yielded a good concordance (ICC, 0.94 [0.88–0.97]). In conclusion, there was better concordance with the counting system, and concordance was high when the assessed field was predetermined, indicating that the selection of the evaluation area is critical for obtaining reproducible Ki67 LI in breast cancer.     

Ki67 index changes, pathological response and clinical benefits in primary breast cancer patients treated with 24 weeks of aromatase inhibition

Aromatase inhibitor shows efficacy for hormone receptor positive postmenopausal breast cancer. We evaluated the activity of 24 weeks of aromatase inhibition with exemestane for primary breast cancer in a neoadjuvant setting. Patients with stage II/IIIA invasive breast cancer with estrogen receptor (ER) and/or progesterone receptor (PgR)-positive status were eligible. Primary endpoints were objective response rate (ORR) and safety. A steroidal aromatase inhibitor exemestane of 25 mg/day was administered for 16 weeks with an 8-week extension. Secondary endpoints were rates of breast-conserving surgery (BCS), and change of Ki67 index and ER/PgR expression in central laboratory analyses. Between March 2006 and December 2007, 116 patients were enrolled. Among those, 102 patients completed 24 weeks of administration. The ORR was 47% (55/116) at Week 16 and 51% (59/116) at Week 24, respectively. No serious toxicity was seen. ORR was associated with ER Allred scores but not with PgR scores. The significant reduction in Ki67 index was confirmed. No progression was experienced in tumors with less than 15% Ki67 index. Pathological response was observed in 28 (30%) of 94 evaluated cases. No statistical correlation between pre-treatment Ki67 index and pathological response was detected; however, a trend of correlation was found between the post-treatment preoperative endocrine prognostic index (PEPI), a prognostic score and the pathological response. At diagnosis, 59 patients (51%) would have required mastectomy but 40 patients were converted to BCS, showing an increase in the rate of BCS (77%). The 24-week aromatase inhibition provided preferable clinical benefits with significant reduction in Ki67 index. More precise mechanisms of the response need to be investigated.     

Prognostic value of Ki-67 labeling index in patients with node-negative, triple-negative breast cancer

The aim of this analysis was to investigate the usefulness of Ki-67 labeling index (LI) for the identification of different prognostic subgroups in primary node-negative, triple negative breast cancer (TNBC) patients. From January 1997 to December 2005, 1,053 patients operated for TNBC were identified through the institutional clinical database. The study was performed in accordance with REMARK criteria. The relationship between Ki-67LI and the risk of breast-related deaths was evaluated with a multivariable Cox regression model. Cubic splines were used to model Ki-67LI as a continuous variable. We selected 496 consecutive patients with node-negative TNBC. Median age was 52 years, median Ki-67LI 48% (range 4-95), and median follow up 6 years (range 0.5-13). Total deaths and deaths from BC were 52 (10.5%) and 38 (7.7%), respectively. Ki-67LI increased with decreasing age (P<0.01), increasing tumor size (P<0.01), and grade (P<0.01). When analyzing Ki-67LI as a continuous variable, the risk of death from BC increased steeply with increasing Ki-67LI up to about 35% and remained flat for higher values (adjusted effect of Ki-67 P=0.049; adjusted nonlinear effect P=0.021). Accordingly, when dividing patients into lower (≤35%) and higher (>35%) Ki-67LI subgroups, the 5-year cumulative incidence of breast-related deaths were 2.3 and 9.0%, respectively, with an adjusted HR(>35 vs ≤35) of 2.3 (95% CI 1.0-5.8, P=0.046). Within the group of patients with node-negative TNBC, Ki-67LI was associated with different prognoses subgroups. Ki-67LI might be useful in the design of trials of risk-adapted adjuvant therapies.     

Influence of body mass index on clinicopathological factors including estrogen receptor,progesterone receptor,and Ki67 expression levels in breast cancers

Background

High body mass index (BMI) is associated not only with a higher incidence of breast cancers but also with poorer prognosis. It is speculated that both enhanced production of estrogens and other factors associated with obesity are involved in these associations, but the biological characteristics associated with high BMI have yet to be thoroughly identified.

Methods

We studied 525 breast cancers, focusing on biological differences between tumors associated with high and low BMI and by immunohistochemically defined intrinsic subtype. Ki67 expression levels were used to differentiate luminal A from luminal B estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)-breast cancers.

Results

Premenopausal patients with high BMI showed a significantly higher frequency of lymph node metastasis (46.4 % vs. 22.9 %, P = 0.005) and tended to have a larger tumor size (P = 0.05) and higher nuclear grade (P = 0.07) than those with low BMI. These differences were not observed among postmenopausal patients. BMI was not associated with distribution of breast cancer subtypes, and ER, progesterone receptor (PR), and Ki67 expression levels of each subtype showed no differences between high and low BMI among premenopausal patients.

Conclusion

Higher BMI might influence aggressive tumor characteristics among premenopausal patients, but its influence on ER, PR, and Ki67 expression levels seems to be limited.     

Immunohistochemical Ki67 labeling index has similar proliferation predictive power to various gene signatures in breast cancer

The objective of this study was to examine the association between the immunohistochemical Ki67 labeling index (IHC Ki67), Ki67 mRNA expression level, and first-generation gene signatures in a cohort of breast cancer patients. We assessed associations between IHC Ki67 and first-generation gene signatures in a panel of 39 tumor samples, using an oligonucleotide microarray. Gene expression analyses included Ki67 alone (MKi67), 21-gene signature, mitosis kinome score signature, and genomic grade index. Correlation coefficients were calculated by Spearman's rank correlation test. In all cases, IHC Ki67, MKi67, and three genetic markers were highly correlated (ρ, 0.71-0.97). Estrogen receptor (ER)-positive cases showed strong correlations between IHC Ki67 and other signatures (ρ, 0.79-0.83). The ER-negative cases showed slightly lower correlations (ρ, 0.58-0.73). In ER-positive cases, the low IHC Ki67 group showed significantly longer relapse-free survival than the high IHC Ki67 group (P = 0.007). This difference was confirmed by multivariate analysis. Our data indicate that IHC Ki67 shows similar predictive power for proliferation in ER-positive cancers as genomic markers. Further study of IHC Ki67 is needed to define prognostic factors and predictive factors for chemotherapy using central laboratory assessment.     

Confirmation of a prognostic index for patients with metastatic breast cancer treated by endocrine therapy

Summary We have previously reported a retrospectively constructed index which can accurately predict survival at the time of diagnosis of symptomatic metastatic breast cancer. The index, derived from a Cox model, is scored: Index score = (4 × Grade) – (6 × ER) + (4 × SIMD) – (0.1 × DFI), where histological grade is scored 1–3 (good, moderate, or poor), oestrogen receptor (ER) is scored 0 (negative) or 1 (positive), site of initial metastasis (SIMD) is scored 1–4 for bone only, lung only, bone and lung, or visceral metastases, respectively, and disease-free interval (DFI) is measured in months. Patients were divided into three prognostic groups on the basis of index score.In the present study we have tested this index prospectively on a new group of 147 patients with metastatic breast cancer. The percentage of patients in each of the three groups was similar between the retrospective and prospective studies. In the prospective study the difference in survival between the 3 groups was highly significant (p<0.001), confirming our retrospective analysis. No single one of the four factors was as powerful in predicting survival as the index itself. We now use this index in our patient management.     

P-glycoprotein immunostaining correlates with ER and with high Ki67 expression but fails to predict anthracycline resistance in patients with advanced breast cancer

Summary In an attempt to further define the clinical utility of p-glycoprotein immunostaining in breast cancer, we examined 101 specimens from patients with advanced breast cancer. There was a significant correlation between estrogen receptor status and p-glycoprotein expression but only for low levels of p-glycoprotein. Premenopausal status appeared to correlate with increased p-glycoprotein expression, but this probably reflects patient selection as premenopausal patients had higher prior exposure to anthracyclines and were more likely to have received chemotherapy as initial treatment. P-glycoprotein expression was highly significantly correlated with expression of the proliferation related antigen Ki67, suggesting that p-glycoprotein expression may well be cell cycle dependent, with overexpression occurring in rapidly cycling cells. These findings may explain reported findings of modulation of p-glycoprotein expression by agents such as anti-oestrogens. P-glycoprotein positive staining did not, however, predict chemotherapy treatment failure or survival duration.     

Relationship between estrogen receptor,progesterone receptor,HER-2 and Ki67 expression and efficacy of aromatase inhibitors in advanced breast cancer

BackgroundSurprisingly few data are published on the relevance of even commonly used biomarkers of response to aromatase inhibitors (AIs) in advanced breast cancer. Here, we aim to determine the effectiveness of AIs in that setting according to quantitative levels of estrogen receptor (ER), progesterone receptor (PgR) and Ki67 or human epithelial growth factor receptor-2 (HER-2) status.Patients and methodsER, PgR, HER-2 and Ki67 protein expressions were centrally assessed in 177 archival formalin-fixed paraffin-embedded primary or locally recurrent breast tumours from women who subsequently received AI treatment of advanced disease.ResultsAmong ER-positive patients (n = 146), higher PgR, but not ER, levels were associated with increased time to AI treatment failure (TTF). Higher Ki67 staining was associated with decreased TTF. ER-positive/HER-2-positive patients showed a non-significant trend for decreased TTF compared with ER-positive/HER-2-negative patients. PgR level, but not Ki67, remained a significant predictor of TTF in multivariate analysis of ER-positive patients.ConclusionsHigher PgR and Ki67 levels are significantly associated with increased and decreased TTF, respectively, in ER-positive patients receiving AI treatment of advanced disease. The higher proliferation seen in PgR-negative tumours does not explain the poorer clinical responsiveness of this subgroup.     

Proliferating macrophages associated with high grade, hormone receptor negative breast cancer and poor clinical outcome

Macrophages, a key cell in the inflammatory cascade, have been associated with poor prognosis in cancers, including breast cancer. In this study, we investigated the relationship of a subset of macrophages??proliferating macrophages (promacs)??with clinico-pathologic characteristics of breast cancer, including tumor size, grade, stage, lymph node metastases, hormone receptor status, subtype, as well as early recurrence, and survival. This study included a discovery and validation set that was conducted at two institutions and laboratories (University of California, San Francisco and University of Chicago) using two independent cohorts of patients with breast cancer. Formalin-fixed, paraffin-embedded sections and/or tissue microarrays were double-stained with anti-CD68 (a macrophage marker) and anti-PCNA (a proliferation marker) antibodies. The presence of intratumoral promacs was significantly correlated with high grade, hormone receptor negative tumors, and a basal-like subtype. In contrast, there was no correlation between promacs and tumor size, stage, or the number of the involved lymph nodes. These findings were consistent between the two study cohorts. Finally, promac numbers were a significant predictor of recurrence and survival. In the pooled analysis, elevated promac levels were associated with a 77% increased risk of dying (P?=?0.015). The presence of promacs in human breast cancer may serve as a prognostic indicator for poor outcomes and early recurrence and serve as a potential cellular target for novel therapeutic interventions.     

High estrogen receptor expression and low Ki67 expression are associated with improved time to progression during first-line endocrine therapy with aromatase inhibitors in breast cancer

Background  

Aromatase inhibitors have played a central role in endocrine therapy for estrogen receptor (ER)-positive breast cancer in postmenopausal women. However, many breast cancer patients with tumors expressing ER are unresponsive to aromatase inhibitors, and all patients with advanced disease eventually develop resistance to the therapy.     

Androgen receptor genotypes predict response to endocrine treatment in breast cancer patients

Background:

The androgen receptor (AR) is frequently expressed in breast cancers. The AR genotype may affect disease-free survival and response to endocrine therapy.

Methods:

In all, 634 women undergoing breast cancer surgery between 2002 and 2008 were followed until 30 June 2010. Six haplotype-tagging single-nucleotide polymorphisms in the AR, and the resulting AR diplotypes, were examined in relation to breast cancer patient characteristics, tumour characteristics, disease-free survival, and response to endocrine treatment.

Results:

Five common AR diplotypes were found. Seventeen rare variants were combined into a composite group. The resulting six AR diplotype groups were clustered into two subgroups, groups A (n=128) and B (n=499), with three diplotypes in each. Patients in group B had larger total breast volume (P=0.024), higher body mass index (BMI) (P=0.050), more axillary lymph node involvement (P_trend=0.020), and higher histological grade (P_trend=0.031). There were 59 breast cancer events in the 569 patients with invasive cancers and no preoperative treatment. Patients in group B also had shorter disease-free survival (P=0.037) than patients in group A. Among patients in group B with oestrogen receptor α positive tumours, tamoxifen (TAM) treatment was associated with longer disease-free survival (P=0.008), while treatment with aromatase inhibitors (AIs) was not (P=0.94). Response to endocrine treatment could not be predicted based on BMI, suggesting that the effect of AR diplotypes went beyond that of a higher BMI.

Conclusion:

A marker for a group of patients who responded to TAM, but not to AIs, was identified. If this finding is confirmed, AR genotyping may provide useful information for selection of endocrine treatment of breast cancer patients.     

Comparison between Ki67 labeling index determined using image analysis software with virtual slide system and that determined visually in breast cancer

Background

In recent papers, Ki67 labeling index (LI) has been used to classify breast cancer patients into the low and high Ki67LI groups for comparison studies, which showed significant differences in many prognostic factors. It has not been clarified whether image analysis software can be used for calculating LI in breast cancer. In our study, we examined whether Ki67LI in breast cancer calculated using image analysis software correlates with that measured on the basis of visual.

Methods

Fifty patients were randomly selected among breast cancer patients who underwent surgical operation from March, 2010 to May, 2010 in our hospital without preoperative chemotherapy. In this study, for the virtual slide system (VSS: VS120-L100, Olympus, Tokyo, Japan), the high-resolution VSs of all the 50 patients were prepared as samples. The image analysis software use for calculating LI was Tissuemorph Digital Pathology (Tissuemorph DP: Visiopharm, Hoersholm, Denmark). The calculated LI was extracted from 3 to 5 views containing hot spots. The LI calculated using Tissuemorph DP was designed as LI/image/T. The digital image of 3 to 5 LI/image/T views was printed out, and on the digital photograph, we counted visually the number of Ki67-immunopositive cells in exactly the same area, and the percentage of Ki67-immunopositive cells was designed as LI/direct. Moreover, a pathologist’s assistant (PA) determined the tumor area in the same specimen using VSS and calculated LI using Tissuemorph DP, which was designed as LI/image/PA. The chief pathologist (CP) similarly calculated LI which was designed as LI/image/CP. We evaluated the degree of agreement between different data sets “LI/image/T and LI/direct” and “LI/image/T, LI/image/CP, and LI/image/PA” by using interclass correlation coefficient (ICC).

Results

The average counts of cells were as follows: LI/direct, 3209.7 ± 1970.4 (SD); LI/image/T, 2601.6 ± 1697.1; LI/image/PA, 2886.5 ± 2027.5; LI/image/CP, 18805.5 ± 22293.4. The values of LI/direct and LI/image/T showed almost perfect agreement as showed by an ICC of 0.885 (95 % CI, 0.806–0.933; p < 0.001). The agreement among three investigators was almost perfect. The obtained ICC was 0.825 (95 % CI, 0.739–0.890; p < 0.001) among the data of LI/image/T, LI/image/CP and LI/image/PA. There were five cases that immunopositivity for Ki67 showed a more than 10 % disagreement between LI/direct and LI/image/T.

Conclusion

The merits of calculating Ki67 LI using Tissuemorph DP are as follows. First, the staining intensity of the cells to be counted can be adjusted. Second, the portion of a tumor including “hot spots” for counting can be chosen. Third, many cancer cells can be counted more rapidly using Tissuemorph DP than by visual observation. However, it is important that pathologist should check and carry out the final decision of the data, when Ki67 LI using Tissuemorph DP is calculated.

     

Biology of progesterone receptor loss in breast cancer and its implications for endocrine therapy.

The response to endocrine therapy in breast cancer correlates with estrogen receptor (ER) and progesterone receptor (PR) status. ER-positive/PR-negative breast cancers respond less well to selective ER modulator (SERM) therapy than ER-positive/PR-positive tumors. The predictive value of PR has long been attributed to the dependence of PR expression on ER activity, with the absence of PR reflecting a nonfunctional ER and resistance to hormonal therapy. However, recent clinical and laboratory evidence suggests that ER-positive/PR-negative breast cancers may be specifically resistant to SERMs, whereas they may be less resistant to estrogen withdrawal therapy with aromatase inhibitors, which is a result inconsistent with the nonfunctional ER theory. Novel alternative molecular mechanisms potentially explaining SERM resistance in ER-positive/PR-negative tumors have been suggested by recent experimental indications that growth factors may downregulate PR levels. Thus, the absence of PR may not simply indicate a lack of ER activity, but rather may reflect hyperactive cross talk between ER and growth factor signaling pathways that downregulate PR even as they activate other ER functions. Therefore, ER-positive/PR-negative breast tumors might best be treated by completely blocking ER action via estrogen withdrawal with aromatase inhibitors, by targeted ER degradation, or by combined therapy targeting both ER and growth factor signaling pathways. In this review, we will discuss the biology and etiology of ER-positive/PR-negative breast cancer, highlighting recent data on molecular cross talk between ER and growth factor signaling pathways and demonstrating how PR might be a useful marker of these activities. Finally, we will consider the clinical implications of these observations.     

Stage III and oestrogen receptor negativity are associated with poor prognosis after adjuvant high-dose therapy in high-risk breast cancer

We report on the efficacy and toxicity of a sequential high-dose therapy with peripheral blood stem cell (PBSC) support in 85 patients with high-risk stage II/III breast cancer. There were 71 patients with more than nine tumour-positive axillary lymph nodes. An induction therapy of two cycles of ifosfamide (total dose, 7.5 g m(-2)) and epirubicin (120 mg m(-2)) was given, and PBSC were harvested during G-CSF-supported leucocyte recovery following the second cycle. The PBSC-supported high-dose chemotherapy consisted of two cycles of ifosfamide (total dose, 12,000 mg m(-2)), carboplatin (900 mg m(-2)) and epirubicin (180 mg m(-2)). Patients were autografted with a median number of 3.7 x 10(6) CD34+ cells kg(-1) (range, 1.9-26.5 x 10(6)) resulting in haematological reconstitution within approximately 2 weeks following high-dose therapy. The toxicity was moderate in general, and there was no treatment-related toxic death. Twenty-one patients relapsed between 3 and 30 months following the last cycle of high-dose therapy (median, 11 months). The probability of disease-free and overall survival at 4 years were 60% and 83%, respectively. According to a multivariate analysis, patients with stage II disease had a significantly better probability of disease-free survival (74%) in comparison to patients with stage III disease (36%). The probability of disease-free survival was also significantly better for patients with oestrogen receptor-positive tumours (70%) compared to patients with receptor-negative ones (40%). Bone marrow samples collected from 52 patients after high-dose therapy were examined to evaluate the prognostic relevance of isolated tumour cells. The proportion of patients presenting with tumour cell-positive samples did not change in comparison to that observed before high-dose therapy (65% vs 71%), but a decrease in the incidence and concentration of tumour cells was observed over time after high-dose therapy. This finding was true for patients with relapse and for those in remission, which argues against a prognostic significance of isolated tumour cells in bone marrow. In conclusion, sequential high-dose chemotherapy with PBSC support can be safely administered to patients with high-risk stage II/III breast cancer. Further intensification of the therapy, including the addition of non-cross resistant drugs or immunological approaches such as the use of antibodies against HER-2/NEU, may be envisaged for patients with stage III disease and hormone receptor-negative tumours.     

Pre-treatment hormonal receptor status and Ki67 index predict pathologic complete response to neoadjuvant trastuzumab/taxanes but not disease-free survival in HER2-positive breast cancer patients

Trastuzumab-containing neoadjuvant chemotherapy achieves a pathologic complete response (pCR) rate of about 40?% in HER2-positive breast cancers, and pCR predicts better survival. A cohort of 102 consecutive Chinese HER2-positive stage II/III patients with neoadjuvant trastuzumab/taxanes were retrospectively analyzed, to evaluate the role of hormonal receptor (HR) status and Ki67 index, along with other parameters, in pCR and survival prediction. pCR rate of the cohort was 44.1?% (45/102). Fifty-three patients were HR-positive and 49 were HR-negative. Median Ki67 index was 40?%, and 49 patients had a high Ki67 index (>40?%) whereas 53 had a low Ki67 index (??40?%). HR status and Ki67 index were confirmed as the only two parameters associated with pCR in multivariate analysis (hazard ratio?=?2.952; 95?% CI, 1.227?C7.105; P?=?0.016 for HR status and hazard ratio?=?2.583, 95?% CI 1.107?C6.026, P?=?0.028 for Ki67 index). Patients with coexisting HR-negative and high Ki67 index had higher pCR rate (69.2?%), compared to those with either HR-negative alone or high Ki67 alone (hazard ratio?=?3.038; 95?% CI, 1.102?C8.372; P?=?0.029), and to those with coexisting HR-positive and low Ki67 index as well (hazard ratio?=?7.071; 95?% CI, 2.150?C23.253; P?=?0.001). In a median follow-up duration of 25.9?months, 11 disease-free survival events (DFS) were recorded. pCR predicted better DFS (log rank P?=?0.018) and was the only significant factor in Cox regression analysis (hazard ratio?=?0.184; 95?% CI, 0.038?C0.893; P?=?0.036). Our study indicates that HR status and Ki67 index are predictors for pCR but not for DFS in HER2-positive patients with neoadjuvant trastuzumab/taxanes, which deserves further investigations.     

Effect of tamoxifen on Ki67 labelling index in human breast tumours and its relationship to oestrogen and progesterone receptor status.

This study aimed to investigate the effect of tamoxifen on breast tumour levels of oestrogen and progesterone receptor (ER and PR) and proliferation as defined by the Ki67 antibody. A group of primary breast cancer patients was randomised to receive either tamoxifen (n = 59) or placebo (n = 44) treatment in the interval between clinic and surgery (median 21 days). Frozen sections of breast tumour biopsies obtained before and after treatment were stained immunocytochemically to obtain the percentage of nuclei containing ER and PR, and a Ki67 labelling index (LI). Tamoxifen-treated patients had a median Ki67 LI of 5.6% in the first biopsy falling to 3.0% in the second biopsy (P < 0.001 by Wilcoxon''s matched pairs test), whereas placebo-treated patients had a median Ki67 LI of 5.4% in the first biopsy and 5.75% in the second (no significant difference). No significant differences were observed when the median %ER or %PR staining before and after treatment were compared. The Ki67 LI tended to increase with increasing histological grade and was greater in tumours that were ER - ve compared to those that were ER + ve (> 5% nuclei stained), median 7.8% and 4.3% respectively (P = 0.011 by Mann-Whitney U-test). However, the decline in tumour Ki67 LI following anti-oestrogen treatment failed to correlate with ER and PR status or to predict recurrence over a short follow-up period. To our knowledge, this is the first time that tamoxifen treatment has been shown to reduce the Ki67 LI in human breast tumours in vivo. These data indicate that staining with the Ki67 antibody may be useful in monitoring response to anti-oestrogen therapy.     

Tumor nuclear grade,estrogen receptor,and progesterone receptor: Their value alone or in combination as indicators of outcome following adjuvant therapy for breast cancer

Summary Previous reports by us have shown that the outcome of breast cancer patients who have received systemic adjuvant therapy is influenced by tumor estrogen or progesterone receptor (ER or PR) content or by nuclear grade. This publication provides information regarding the relative merit of those three markers. Findings from patients receiving L-PAM plus 5-FU (PF) or PF plus tamoxifen (PFT) indicate that the disease-free survival and survival within each regimen was almost identical when related to either ER, PR, or nuclear grade. Those having tumors with either of the receptors 10 fmol or a good nuclear grade had a better outcome through five postoperative years than did those with ER or PR 0–9 fmol or poor nuclear grade. The magnitude of the difference was similar for each of the three discriminants. Since they were found to be of equal predictive value, one marker might well serve as a substitute for another. Cox regression analyses, however, clearly indicate that ER, PR, and nuclear grade have an independent influence on outcome and that a more accurate assessment of outcome is obtained when more than one marker is employed. Thus, information should be obtained on as many markers as possible. This conclusion is supported by observations presented which indicate that nuclear grade in combination with either or both of the receptors is a better predictor than either marker alone and that, as indicated by life table probability values and relative odds ratios, an increasing number of favorable tumor prognostic indicators results in a better patient outcome particularly in PFT-treated patients. A possible explanation is considered for why the separation of receptor/nuclear grade categories is more orderly and pronounced in PF-treated patients receiving tamoxifen than in those given PF alone. See Appendix I     

Ki67 measured in metastatic tissue and prognosis in patients with advanced breast cancer

The purpose of this study is to determine the prognostic role of Ki67 evaluated in relapse biopsies from patients with metastatic breast cancer (MBC). Two hundred and ten patients diagnosed with MBC in Stockholm, Sweden between 1998 and 2009 and with Ki67 assessed at time of first systemic relapse (mKi67) were retrospectively identified and divided into two groups according to mKi67 fraction (low ≤20 %, high >20 %). Post-relapse survival was compared between the groups using Kaplan–Meier and Cox regression methods. Death rate as function of continuous mKi67 was also evaluated. Furthermore, the prognostic role of intra-individual change in Ki67 between primary tumor and matched metastasis was explored by Kaplan–Meier plots. One hundred and twenty-five patients had low and 85 had high mKi67. Median survival was 25 and 17 months in low- and high-mKi67 group, respectively [hazard ratio (HR) 0.69, 95 % confidence intervals (CI) 0.51–0.92, P = 0.01]. In a multivariate model adjusted for prognostic confounders, low-mKi67 showed a non-significant trend toward better survival (HR 0.85, 95 %CI 0.62–1.16, P = 0.30). Nevertheless, mKi67 independently correlated with survival when compared with primary tumor proliferation (HR 0.56, 95 %CI 0.38–0.81, P = 0.002). The 2-year death rate steeply increased as mKi67 increased. Moreover, the change from high in primary tumor to low in metastasis significantly correlated with longer survival when compared with stable Ki67 levels (HR 0.48, 95 %CI 0.31–0.76, P = 0.002). In this cohort of MBC patients, mKi67 inversely but not independently correlated with survival. However, a significant association between mKi67 and survival was shown regardless of primary tumor proliferation.