Overall survival in Japanese patients with ER+/HER2- advanced breast cancer treated with first-line palbociclib plus letrozole.

BACKGROUND: An open-label, single-arm, Japanese phase 2 study (J-Ph2) investigated the efficacy and safety of first-line (1L) palbociclib (PAL) + letrozole (LET) in postmenopausal Japanese women with ER+/HER2- advanced breast cancer (ABC). In the final analysis, median progression-free survival was 35.7 months (95% CI 21.7-46.7); but overall survival (OS) data were immature. Here, we report the findings from a follow-up study of J-Ph2 (NCT04735367) evaluating OS and subsequent therapy in these Japanese women. METHODS: Patients (N = 42) who participated in J-Ph2 were enrolled in the OS follow-up study. The primary endpoint was OS and secondary endpoints included type and duration of subsequent therapy. RESULTS: Patients were a median age of 62.5 years; 48% had visceral metastases. At a median follow-up of 89.7 months, the median OS was 85.4 months (95% CI 64.3-not estimable). Median OS was longer in patients with nonvisceral versus visceral metastases (not reached vs 67.3 months), or with treatment-free interval > 12 months versus ≤ 12 months (85.4 vs 45.4 months), or with treatment duration ≥ 24 months versus < 24 months (not reached vs 47.5 months). Of patients who received a first subsequent therapy (81%), most (67%) continued endocrine-based therapy, while 7% received chemotherapy. The median duration of the first subsequent therapy was 8.3 months (95% CI 3.9-12.2), and the median chemotherapy-free survival was 69.1 months (95% CI 24.2-85.4). CONCLUSIONS: In this population of Japanese women with ER+/HER2- ABC, median OS was over 7 years with 1L PAL + LET, supporting the use of 1L PAL + endocrine therapy. TRIAL NUMBER: NCT04735367.

Efficacy and safety of pegfilgrastim biosimilar MD-110 in patients with breast cancer receiving chemotherapy: Single-arm phase III.

INTRODUCTION: Pegfilgrastim is indicated to decrease the incidence of chemotherapy-induced febrile neutropenia. It is the first granulocyte-colony stimulating factor approved for prophylactic use regardless of carcinoma type and is marketed in Japan as G-LASTA (Kyowa Kirin Co., Ltd., Tokyo, Japan). MD-110 is a biosimilar of pegfilgrastim. This phase III, multicenter, open-label, single-arm study investigated the efficacy and safety of MD-110 in early-stage breast cancer patients receiving neoadjuvant or adjuvant myelosuppressive chemotherapy. METHODS: A total of 101 patients received the study drug. Each patient received docetaxel 75 mg/m2 and cyclophosphamide 600 mg/m2 (TC) for four cycles on day 1 of each cycle. MD-110 (3.6 mg) was administered subcutaneously on day 2 of each cycle. The primary efficacy endpoint was the duration of severe neutropenia during cycle 1 (days with absolute neutrophil count < 500/mm3 ). The safety endpoints were adverse events and the presence of antidrug antibodies. RESULTS: The mean (SD) duration of severe neutropenia for MD-110 was 0.2 (0.4) days. The upper limit of the two-sided 95% confidence interval for the mean duration of severe neutropenia was 0.2 days, below the predefined threshold of 3.0 days. The incidence of febrile neutropenia, the secondary efficacy endpoint, was 6.9% (7/101). Adverse events, occurring in more than 50% of patients, were alopecia, constipation, and malaise, which are common side effects of TC chemotherapy. Antidrug antibodies were negative in all patients. CONCLUSION: MD-110 was effective against chemotherapy-induced neutropenia. No additional safety concern, compared with the originator, was observed in patients with breast cancer receiving TC chemotherapy.(JapicCTI-205230).

Granzyme B Expression in the Tumor Microenvironment as a Prognostic Biomarker for Patients with Triple-Negative Breast Cancer.

Tumor-infiltrating lymphocytes in the tumor microenvironment are important in the treatment of triple-negative breast cancer (TNBC). Cytotoxic T cells produce cytokines and cytotoxic factors, such as perforin and granzyme, which induce apoptosis by damaging target cells. To identify biomarkers of these cells, we investigated granzyme B (GZMB) in the tumor microenvironment as a biomarker of treatment response and prognosis in 230 patients with primary TNBC who underwent surgery without preoperative chemotherapy between January 2004 and December 2014. Programmed cell death ligand 1 (PD-L1) positivity was defined as a composite positive score ≥10 based on the PD-L1 immunostaining of tumor cells and immune cells. GZMB-high was defined as positivity in ≥1% of tumor-infiltrating lymphocytes (TILs). Among the 230 TNBC patients, 117 (50.9%) had CD8-positive infiltrating tumors. In the PD-L1-positive group, a Kaplan-Meier analysis showed that GZMB-high TNBC patients had better recurrence-free survival (RFS) and overall survival (OS) than GZMB-low patients and that OS was significantly longer (RFS: p = 0.0220, OS: p = 0.0254). A multivariate analysis also showed significantly better OS in PD-L1- and GZMB-high patients (hazard ratio: 0.25 (95% IC: 0.07-0.88), p = 0.03). Our findings indicate that GZMB is a useful prognostic biomarker in PD-L1-positive TNBC patients.

An evaluation of lymphovascular invasion in relation to biology and prognosis according to subtypes in invasive breast cancer.

Lymphovascular invasion (LVI) is associated with a poor outcome in breast cancer. The purpose of the present study was to evaluate the clinical significance of LVI in primary breast cancer and to investigate disease-free survival as a prognostic marker according to the breast cancer subtypes. This study examined 4,652 consecutive cases of invasive breast cancer excluding the patients with non-invasive cancer, stage IV and those who underwent neo-adjuvant therapy from February 2002 to February 2021. The clinicopathological characteristics and prognosis of LVI-positive and -negative tumors were compared. LVI was evaluated in H&E staining specimens from surgically resected samples. The LVI expression rates were 29.2% (low, 19.7%; high, 9.5%) in all primary cases. The LVI-positive rate was significantly associated with specimens with the following characteristics: ER/PgR-negative, HER2-positive, p53 overexpression, higher Ki-67 index values, higher nuclear grade, positive nodes and larger tumors. Moreover, the subtypes were significantly associated with LVI positivity; 20% in Luminal A, 34.6% in Luminal B, 40.9% in Lumina/HER2, 38.1% in HER2-enriched and 29.8% in triple negative (TN). There were significant differences in disease-free survival between LVI status in Luminal A, Luminal B and TN subtypes, but there was no difference in the Luminal/HER2 and HER2-enriched subtypes. A multivariate analysis revealed that LVI was a significant factor in Luminal B and TN subtypes. Overall, LVI was significantly associated with the advanced and aggressive characteristics in breast cancer. Luminal A type had a lower LVI rate, and HER2 type had a higher LVI rate. Moreover, LVI was a significant prognostic factor in Luminal B and TN subtypes. These data suggested that the LVI status was useful in predicting the prognosis in HER2 negative breast cancer cases.

Triple Negative Breast Cancer: An Analysis of the Subtypes and the Effects of Menopausal Status on Invasive Breast Cancer.

BACKGROUND: Triple negative breast cancer (TNBC) is a subtype of breast cancer which lacks hormone receptor (HR) expression and HER2 gene amplification and is the most aggressive subtype, with a heterogeneous genetic profile. The aim of this retrospective study was to evaluate the clinical significance of menopausal status in breast cancer cases with TNBC. METHODS: Primary breast cancer patients who underwent curative surgery were enrolled in this retrospective study. A total of 5153 invasive breast cancer cases with Stage I-III were analyzed. The distribution of cases according to the menopausal status and subtypes was investigated and the clinicopathological characteristics and prognosis were compared between pre- and postmenopausal TNBC patients. RESULTS: TNBC was frequently seen in postmenopausal patients and Luminal B and Luminal/HER2 subtypes were more common in premenopausal patients. There was no difference in DFS in the Luminal A/B and HER2 subtypes, but a significant difference was seen in the TNBC patients. Premenopausal patients with TNBC frequently had an overexpression of the p53 protein, a significantly higher Ki-67 index value, and a higher nuclear grade. A multivariate analysis revealed that menopausal status, nodal status, and tumor size were significant factors for DFS in TNBC cases. CONCLUSION: Menopausal status significantly correlates with breast cancer subtypes. TNBC was often seen in postmenopausal patients and these patients tend to have more favorable factors and a better DFS than premenopausal patients. These findings suggest that menopausal status is an important factor for evaluating biology and prognosis in TNBC cases.

The efficacy and safety of pertuzumab plus trastuzumab and docetaxel as a first-line therapy in Japanese patients with inoperable or recurrent HER2-positive breast cancer: the COMACHI study.

PURPOSE: In the CLEOPATRA study of patients with human epidermal growth factor receptor 2 (HER2)-positive recurrent or metastatic breast cancer, the Japanese patient subgroup did not demonstrate the improved progression-free survival (PFS) of pertuzumab plus trastuzumab and docetaxel vs. placebo that was seen in the overall population. Therefore, COMACHI was conducted to confirm the efficacy and safety of this treatment regimen in this patient subgroup. METHODS: This was a phase IV study of pertuzumab plus trastuzumab and docetaxel in Japanese patients with histologically/cytologically confirmed inoperable or recurrent HER2-positive breast cancer. All patients received pertuzumab, trastuzumab, and docetaxel intravenously every 3 weeks until disease progression/unacceptable toxicity. The primary endpoint was investigator-assessed PFS. Secondary endpoints were overall survival (OS), investigator-assessed objective response rate, and duration of response (DoR). Safety was also assessed. RESULTS: At final analysis, median investigator-assessed PFS was 22.8 months (95% CI 16.9-37.5). From first dose, OS rate at 1 year was 97.7%; and at 2 and 3 years were 88.5% and 79.1%, respectively. Of the 118 patients with measurable disease at baseline, response rate was 83.9% (95% CI 77.3-90.5) and median investigator-assessed DoR was 26.3 months (95% CI 17.1-not evaluable). Treatment was well tolerated, with no new safety signals detected. CONCLUSIONS: Our results suggest similar efficacy and safety for pertuzumab plus trastuzumab and docetaxel in Japanese patients compared with the overall population of CLEOPATRA, providing further support for this combination therapy as standard of care for Japanese patients with inoperable or recurrent HER2-positive breast cancer.

Microsatellite instability in Japanese female patients with triple-negative breast cancer.

BACKGROUND: It is important to identify biomarkers for triple-negative breast cancers (TNBCs). Recently, pembrolizumab, an immune checkpoint inhibitor (ICI) for programmed cell death 1 (PD-1), was approved as a treatment strategy for unresectable or metastatic tumor with high-frequency microsatellite instability (MSI-H) or mismatch repair deficiency, such as malignant melanoma, non-small cell lung cancer, renal cell cancer and urothelial cancer. In addition, results from clinical trials suggested that ICI was a promising treatment for TNBCs with accumulated mutations. However, the frequency of MSI in Japanese TNBCs still remains unclear. We aimed to analyze the presence of MSI-H in TNBCs as a biomarker for ICI therapy. METHODS: In this study, we retrospectively evaluated the MSI of 228 TNBCs using an innovative method, MSI Analysis System Version 1.2 (Promega), consisting of 5 microsatellite markers: BAT-26, NR-21, BAT-25, MONO-27 and NR-24 without a normal tissue control. RESULTS: Among 228 tumors, 222 (97.4%) were microsatellite stable, 4 (1.7%) low-frequency MSI and 2 (0.9%) MSI-H, respectively. Two MSI-H tumors were potentially aggressive pathologically as indicated by nuclear grade 3 and high Ki-67 (> 30%), and were classified as basal-like and non-BRCA-like, but were not consistent regarding tumor-infiltrating lymphocytes, CD8 and PD-L1 expression. CONCLUSIONS: Although we found that MSI-H was uncommon (0.9%) in TNBCs, potential targets for ICIs exist in TNBCs. Therefore, MSI-H breast cancer patients should be picked up using not only conventional methods but also platforms for comprehensive genomic profiling.

T-bet+ lymphocytes infiltration as an independent better prognostic indicator for triple-negative breast cancer.

PURPOSE: T-box transcription factor 21 (T-bet), which is the master regulator of effector T-cell activation, is derived by stimulation of T-cell receptors. In this study, we focused on T-bet and examined the function of activated T cells. METHODS: This study included 242 patients with primary triple-negative breast cancer (TNBC) who underwent resection without neoadjuvant chemotherapy between January 2004 and December 2014. The immunohistochemistry scoring for CD8 and T-bet expression on tumor-infiltrating lymphocytes (TILs) was defined as ≥ 30 per 6.25 × 10-3 mm2. RESULTS: Of the 242 TNBC cases, CD8 was positively expressed in 127 (52.5%) tumors, and T-bet was positively expressed in 67 (27.7%) tumors. T-bet expression was significantly correlated with CD8 expression (p < 0.0001). Patients with T-bet+ tumors had longer overall survival (OS) compared with patients with T-bet- tumors (p = 0.047). The combination of CD8+ and T-bet+ was associated with a better recurrence-free survival (RFS) and OS compared to CD8+/T-bet- tumors (p = 0.037 and p = 0.024, respectively). Adjuvant chemotherapy provided significantly greater benefit to patients with T-bet+ tumors (p = 0.031 for RFS, p = 0.0003 for OS). Multivariate analysis revealed that T-bet expression on TILs was an independent and positive prognostic indicator (HR = 0.36, 95% confidence interval (CI) 0.12-0.94, p = 0.037 for RFS, HR = 0.30, 95% CI 0.07-0.95, p = 0.039 for OS). CONCLUSIONS: OS was significantly improved for patients with high T-bet-expressing TILs in TNBC. Thus, T-bet may be a predictive indicator for survival and various immunotherapy strategies in TNBC.

Ki-67 index value and progesterone receptor status can predict prognosis and suitable treatment in node-negative breast cancer patients with estrogen receptor-positive and HER2-negative tumors.

Gene profiling has identified at least 4 breast cancer subtypes, including Luminal A, Luminal B, HER2-enriched and basal-like, and immunohistochemistry is used as a guide to determine these subtypes. In the present study, patients with ER-positive, HER2-negative and negative nodes were classified into 4 groups according to the PgR and the Ki-67 status and were retrospectively examined. The analysis was based on the clinicopathological findings, and includes the recurrence score (RS) and disease-free survival (DFS) rates. Patients with invasive breast cancer (n=1866) were classified as LA (high PgR/low Ki-67), LB-1 (high PgR/high Ki-67), LB-2 (low PgR/high Ki-67), and LB-3 (low PgR/low Ki-67). In addition, 41 of the cases underwent a 21-gene expression assay. The data revealed that T1 tumors were more prevalent in the LA group and rare in the LB-2 group. Furthermore, nuclear grade 3 and p53 overexpression was revealed to be significantly correlated with LB-2. In terms of prognosis, LA had a significantly more favorable DFS; however, no differences were observed in the LB-3 group. LB-2 had a significantly worse DFS in all cases, and in the cases administered with endocrine therapy alone. Chemotherapy in combination with endocrine therapy was administered to cases with a higher risk of recurrence. In the LB-2 group, there was no difference in the DFS rates between the cases with endocrine therapy and chemo-endocrine therapy. These findings suggest that chemotherapy could improve the DFS in the LB-2 group. In addition, the majority of cases with LA, LB-3 and LB-1 had a RS of ≤25 and the majority of the LB-2 cases had a RS of >25. The patients with LA and LB-3 had a favorable DFS even in the group that received endocrine therapy alone. LB-2 was significantly correlated with a higher degree of malignancy and benefited from chemotherapy. These data suggest that the PgR and the Ki-67 status are effective in predicting prognosis, and for deciding on the most effective treatment strategy in patients with breast cancer.

Associations in tumor infiltrating lymphocytes between clinicopathological factors and clinical outcomes in estrogen receptor-positive/human epidermal growth factor receptor type 2 negative breast cancer.

The value of assessing tumor infiltrating lymphocytes (TILs) in estrogen receptor (ER) positive/human epidermal growth factor receptor type 2 (HER2) negative breast cancer has yet to be determined. In the present study, a total of 184 cases with early distant recurrence detected within 5 years following the primary operation, 134 with late distant recurrence diagnosed following 5 years or longer and 321 controls without recurrence for >10 years following starting the initial treatment for ER-positive/HER2 negative breast cancer, registered in 9 institutions, were analyzed. The distributions of TILs and their clinical relevance were investigated. TIL distributions did not differ significantly among the early, late and no recurrence groups, employing a 30% cut-off point as a dichotomous variable. In those who had received adjuvant chemotherapy as well as endocrine therapy, a trend toward higher TIL proportions was detected when the early recurrence group was compared with the no recurrence group employing the 30% cut-off point (P=0.064). The TIL distributions were significantly associated with nodal metastasis (P=0.004), ER status (P=0.045), progesterone receptor (PgR) status (P=0.002), tumor grade (P=0.021), and the Ki67 labeling index (LI) (P=0.002) in the no recurrence group and with the Ki67 LI in the recurrence groups (P=0.002 in early recurrence group, P=0.023 in late recurrence group). High TIL distributions also predicted shorter survival time following the detection of recurrence (P=0.026). However, these prognostic interactions were not significant in multivariate analysis (P=0.200). The present retrospective study demonstrated no significant interaction between TIL proportions and the timing of recurrence. However, higher TIL proportions were observed in breast cancer patients with aggressive biological phenotypes, which tended to be more responsive to chemotherapy. The clinical relevance of stromal TILs for identifying patients who would likely benefit from additional therapies merits further investigation in a larger patient population.

The combination of PD-L1 expression and decreased tumor-infiltrating lymphocytes is associated with a poor prognosis in triple-negative breast cancer.

This study included patients with primary triple-negative breast cancer (TNBC) who underwent resection without neoadjuvant chemotherapy between January 2004 and December 2014. Among the 248 TNBCs studied, programmed cell death ligand-1 (PD-L1) expression was detected in 103 (41.5%) tumors, and high levels of tumor-infiltrating lymphocytes (TILs) were present in 118 (47.6%) tumors. PD-L1 expression correlated with high levels of TILs, but was not a prognostic factor. Patients with TILs-high tumors had better overall survival than those with TILs-low tumors (P = 0.016). There was a strong interaction between PD-L1 expression and TILs that was associated with both recurrence-free survival (P = 0.0018) and overall survival (P = 0.015). Multivariate Cox proportional hazards model analysis showed that PD-L1-positive/TILs-low was an independent negative prognostic factor for both recurrence-free survival and overall survival. Our findings suggest that PD-L1-positive/TILs-low tumors are associated with a poor prognosis in patients with TNBC, and that it is important to focus on the combination of PD-L1 expression on tumor cells and TILs present in the tumor microenvironment. These biomarkers may be useful for stratification of TNBCs and for predicting prognosis and developing novel cancer immunotherapies.

Post-relapse survival in patients with the early and late distant recurrence in estrogen receptor-positive HER2-negative breast cancer.

BACKGROUND: Few studies have been performed on post-relapse survival in patients with the early and late distant recurrence in estrogen receptor (ER)-positive, HER2-negative breast cancer. METHODS: A total of 205 patients with the early distant recurrence and 134 patients with the late distant recurrence of ER-positive, HER2-negative breast cancer who had undergone breast surgery or neoadjuvant chemotherapy between January 2000 and December 2004 were registered from nine institutions. Prognostic factors for post-relapse survival in patients with the early and late recurrence were analyzed. RESULTS: Post-relapse survival was significantly longer in patients with the late recurrence than in patients with the early recurrence. Predictive factors for post-relapse survival in patients with the early recurrence were lack of adjuvant chemotherapy, a long disease-free interval, and long durations of endocrine therapies and chemotherapies after relapse. In patients with the late recurrence, post-relapse survival was significantly improved for those individuals with one metastatic organ at relapse and individuals who were treated with the first-line and subsequent endocrine therapies for prolonged periods. Moreover, ER expression in primary breast tumors of late recurrence patients was significantly higher with a duration of the first-line endocrine therapy >6 months than in those with a duration ≤6 months. CONCLUSION: Predictors for prognosis after relapse differed between patients with the early and late distant recurrence. Endocrine responsiveness after relapse is a key factor for improved post-relapse survival, and it is thus important to establish whether metastatic tumors are endocrine-resistant in ER-positive, HER2-negative recurrent breast cancer.

BRCAness as a Biomarker for Predicting Prognosis and Response to Anthracycline-Based Adjuvant Chemotherapy for Patients with Triple-Negative Breast Cancer.

BACKGROUND: Triple-negative breast cancer (TNBC) is a heterogeneous tumor that encompasses many different subclasses of the disease. In this study, we assessed BRCAness, defined as the shared characteristics between sporadic and BRCA1-mutated tumors, in a large cohort of TNBC cases. METHODS: The BRCAness of 262 patients with primary TNBCs resected between January 2004 and December 2014 was determined through the isolation of DNA from tumor tissue. Classification of BRCAness was performed using multiple ligation-dependent probe amplification (MLPA). The tumor subtypes were determined immunohistochemically using resected specimens. RESULTS: Of the 262 TNBCs, the results of the MLPA assays showed that 174 (66.4%) tumors had BRCAness. Patients with BRCAness tumors were younger than patients with non-BRCAness tumors (P = 0.003). There was no significant difference between the two groups regarding their pathological stages. The BRCAness group had a significantly shorter recurrence-free survival (RFS) compared with the non-BRCAness group (P = 0.04) and had a shorter overall survival (OS) although this did not reach statistical significance. Adjuvant treatments with anthracycline-based regimens provided significantly greater benefits to the BRCAness group (P = 0.003 for RFS, and P = 0.03 for OS). Multivariate Cox proportional hazard model analysis showed that BRCAness was an independent negative prognostic factor, and the anthracycline-based adjuvant chemotherapy was an independent positive prognostic factor for both RFS and OS in TNBC. CONCLUSIONS: The 66.4% patients of TNBCs showed BRCAness. BRCAness is essential as a biomarker in the subclassification of TNBCs and might be of use for predicting their prognosis. Furthermore, this biomarker might be a predictive factor for the effectiveness of anthracycline-based adjuvant chemotherapy for patients with TNBCs.

Differences in expression of the cancer stem cell marker aldehyde dehydrogenase 1 among estrogen receptor-positive/human epidermal growth factor receptor type 2-negative breast cancer cases with early, late, and no recurrence.

BACKGROUND: The significance of the expression of aldehyde dehydrogenase 1 (ALDH1), a cancer stem cell marker, for predicting the recurrence of estrogen receptor (ER)-positive/human epidermal growth factor receptor type 2 (HER2)-negative breast cancer is still poorly understood. The value of ALDH1 in predicting the time of recurrence remains unknown. METHODS: In total, 184 patients with early distant recurrence, 134 patients with late distant recurrence, and 321 control patients without recurrence for more than 10 years after starting initial treatment for ER-positive/HER2-negative breast cancer, registered in 9 institutions, were analyzed. We assessed relationships between ALDH1 and other clinicopathological features, and ALDH1 expression was compared among the three groups. The relationship between ALDH1 expression and overall survival after recurrence was also evaluated in each group. RESULTS: The rates of ALDH1 expression positivity (more than 1 %) in the early, late, and no recurrence groups were 18.4 %, 13.4 %, and 8.4 %, respectively. ALDH1 expression correlated significantly with lymph node metastases (p = 0.048) and the Ki-67 labeling index (p < 0.001) in the early recurrence group. Multivariate analysis revealed ALDH1 expression to be significantly higher in the early recurrence group than in the no recurrence group (adjusted OR 2.140, 95 % CI 1.144-4.003, p = 0.016). Moreover, there was a significant difference in ALDH1 expression between the early and no recurrence groups receiving adjuvant endocrine therapy and chemotherapy (adjusted OR 4.625, 95 % CI 1.881-12.474, p < 0.001). However, there was no difference in ALDH1 expression between the late and no recurrence groups in univariate analysis (OR 1.507, 95 % CI 0.738-2.998, p = 0.253). In multivariate analysis, ALDH1 was not a factor independently predicting overall survival after the detection of recurrence (adjusted OR 1.451, 95 % CI 0.985-2.085, p = 0.059). CONCLUSIONS: Among patients with ER-positive/HER2-negative breast cancer, ALDH1 expression was more common in those with early recurrence, and this expression was found to be associated with a more aggressive breast cancer phenotype than that in the patients without recurrence. Further study is needed to clarify the prognostic significance of the heterogeneity of cancer stem cells and to confirm their role in resistance to chemotherapy.

Clinicopathological factors predicting early and late distant recurrence in estrogen receptor-positive, HER2-negative breast cancer.

BACKGROUND: Most studies analyzing prognostic factors for late relapse have been performed in postmenopausal women who received tamoxifen or aromatase inhibitors as adjuvant endocrine therapy for estrogen receptor (ER)-positive breast cancer. METHODS: A total of 223 patients (108 premenopausal and 115 postmenopausal) with early distant recurrence and 149 patients (62 premenopausal and 87 postmenopausal) with late distant recurrence of ER-positive, HER2-negative breast cancer who were given their initial treatment between 2000 and 2004 were registered from nine institutions. For each late recurrence patient, approximately two matched control patients without relapse for more than 10 years were selected. Clinicopathological factors and adjuvant therapies were compared among the three groups by menopausal status and age. RESULTS: Factors predicting early recurrence in premenopausal women were large tumor size, high lymph node category and high tumor grade, whereas predictors for late recurrence were large tumor size and high lymph node category. In postmenopausal women under 60 years of age, factors predicting early recurrence were bilateral breast cancer, large tumor size, high lymph node category, low PgR expression and high Ki67 labeling index (LI), while predictors for late recurrence were large tumor size and high lymph node category. On the other hand, in postmenopausal women aged 60 years or older, factors predicting early recurrence were bilateral breast cancer, large tumor size, high lymph node category, high tumor grade, low ER expression and high Ki67 LI, whereas predictors for late recurrence were high lymph node category, low ER expression and short duration of adjuvant endocrine therapy. CONCLUSION: Predictors of early and late distant recurrence might differ according to menopausal status and age.

The importance of tissue handling of surgically removed breast cancer for an accurate assessment of the Ki-67 index.

AIM: Insufficient attention for the Ki-67 immunohistochemistry has been given to the importance of tissue handling for surgical breast cancer specimens. We sought to investigate the effect of fixation status on the Ki-67. METHODS: We examined the effect of fixative, time to and duration of fixation using surgical specimens, and finally, compared the paired Ki-67 index in the tumour between core needle and surgical specimen. RESULTS: The Ki-67 was significantly higher when 10% neutral buffered formalin was used (p=0.0276). Insufficient fixation caused a drastic reduction in the Ki-67 index (p=0.0177), but not significant in oestrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2). Sixteen hours delayed time to fixation also caused a reduction of the Ki-67 (p=0.0284), but not significant in ER. Prolonged fixation significantly led to a gradual reduction in the Ki-67 in a time-dependent manner, but not in both ER and HER2. Finally, cutting the tumour before fixation improved fixation status and consequently caused an increased level of the Ki-67 index (p=0.0181), which resulted in a strong correlation of the Ki-67 between core needle and surgical specimen (r=0.8595). CONCLUSIONS: Tissue handling of surgical specimen is critical for assessing the Ki-67 compared with ER and HER2. We should pay more attention to tissue fixation status for the standard assessment of the Ki-67 index.

A Comparison of the Hot Spot and the Average Cancer Cell Counting Methods and the Optimal Cutoff Point of the Ki-67 Index for Luminal Type Breast Cancer.

OBJECTIVE: In this case-control study, we investigated the most suitable cell counting area and the optimal cutoff point of the Ki-67 index. METHODS: Thirty recurrent cases were selected among hormone receptor (HR)-positive/HER2-negative breast cancer patients. As controls, 90 nonrecurrent cases were randomly selected by allotting 3 controls to each recurrent case based on the following criteria: age, nodal status, tumor size, and adjuvant endocrine therapy alone. Both the hot spot and the average area of the tumor were evaluated on a Ki-67 immunostaining slide. RESULTS: The median Ki-67 index value at the hot spot and average area were 25.0 and 14.5%, respectively. Irrespective of the area counted, the Ki-67 index value was significantly higher in all of the recurrent cases (p < 0.0001). The multivariate analysis revealed that the Ki-67 index value of 20% at the hot spot was the most suitable cutoff point for predicting recurrence. Moreover, higher x0394;Ki-67 index value (the difference between the hot spot and the average area, ≥10%) and lower progesterone receptor expression (<20%) were significantly correlated with recurrence. CONCLUSION: A higher Ki-67 index value at the hot spot strongly correlated with recurrence, and the optimal cutoff point was found to be 20%.

Evaluation of an Optimal Cut-Off Point for the Ki-67 Index as a Prognostic Factor in Primary Breast Cancer: A Retrospective Study.

The Ki-67 index is an important biomarker for indicating the proliferation of cancer cells and is considered to be an effective prognostic factor for breast cancer. However, a standard cut-off point for the Ki-67 index has not yet been established. Therefore, the aim of this retrospective study was to determine an optimal cut-off point in order to establish it as a more accurate prognostic factor. Immunohistochemical analysis of the Ki-67 index was performed on 4329 patients with primary breast cancer from August 1987 to March 2012. Out of this sample, there were 3186 consecutive cases from September 1997 with simultaneous evaluations of ER, PgR and HER2 status. Cox's proportional hazard model was used to perform univariate and multivariate analyses of the factors related to OS. The hazard ratios (HR) and the p values were then compared to determine the optimal cut-off point for the Ki-67 index. The median Ki-67 index value was 20.5% (mean value 26.2%). The univariate analysis revealed that there was a statistically significant negative correlation with DFS and OS and the multivariate analysis revealed that the Ki-67 index value was a significant factor for DFS and OS. The top seven cut-off points were then carefully chosen based on the results of the univariate analysis using the lowest p-values and the highest HR as the main selection criteria. The multivariate analysis of the factors for OS showed that the cut-off point of 20% had the highest HR in all of the cases. However, the cutoff point of 20% was only a significant factor for OS in the Luminal/HER2- subtype. There was no correlation between the Ki-67 index value and OS in any of the other subtypes. These data indicate that the optimal cut-off point of 20% is the most effective prognostic factor for Luminal/HER2- breast cancer.

Efficacy of intraoperative entire-circumferential frozen section analysis of lumpectomy margins during breast-conserving surgery for breast cancer.

BACKGROUND: Intraoperative frozen section analysis of the surgical margins during breast-conserving surgery (BCS) for breast cancer can reliably achieve clear surgical margins and prevent re-operations. The aim of this study was to assess intraoperative entire-circumferential frozen section analysis (IEFSA) of the lumpectomy margins during BCS. METHODS: A total of 1029 patients who underwent BCS with IEFSA between June 2007 and July 2013 were available for assessment. The inner surfaces of the shaved lumpectomy margins were examined as frozen sections during BCS. The margins were defined as positive when the cancer cells were present within 5 mm from the edge of the outermost margins of the specimens. RESULTS: Out of 1029 patients, 312 patients (30.3 %) had positive margins after the initial lumpectomy and underwent additional resections during BCS. Fourteen patients (1.4 %) underwent mastectomy following the results of additional resections during the first surgery. Of 1015 patients who completed BCS, 60 patients (5.9 %) were found to have positive margins in the final pathology. One patient (0.1 %) underwent re-operation after BCS while the residual diseases of the other 59 patients were judged to be minimal. Of the 312 patients who were judged to have positive margins after the initial lumpectomy with IEFSA, 53 patients (16.9 %) were found to have negative margins in the final pathology. At a median follow-up time of 54.1 months, one patient (0.1 %) had a recurrence of breast cancer in the preserved breast. CONCLUSION: IEFSA is useful for preventing the need for re-operation and local recurrence after BCS.