The effect of exercise and educational programs for breast cancer patients on the development of breast cancer-related lymphoedema: secondary endpoint from a randomized controlled trial in the Setouchi Breast Project-10.

BACKGROUND: Although the association between higher physical activity and preventive effect on breast-cancer-related lymphoedema (BCRL) has been reported, it is unclear what intervention is optimal. We aimed to investigate the effect of exercise and educational programs on BCRL development. METHODS: This study was a secondary endpoint analysis from a prospective randomized controlled trial. We enrolled patients with stage 0-III breast cancer from March 2016 to March 2020 and randomly assigned them to the control (n = 111), education (n = 115), or exercise (n = 104) group. As secondary endpoint, we assessed the incidence of and preventive effect on BCRL at 12 months post-intervention. RESULTS: There were no significant differences in the incidence of BCRL at 12 months post-intervention between the exercise and control groups (9.8% and 10.8%, P = 0.83) and the education and control groups (11.6% and 10.8%, P = 1.00). There were no significant differences in time to BCRL onset from the day of surgery between the exercise and control groups (event rate at 12 months: 20.7% and 17.2%, log-rank, P = 0.54) and the education and control groups (18.8% and 17.2%, log-rank, P = 0.57). The multivariable analyses indicated that axillary dissection and obesity significantly increased the risk of BCRL [hazard ratio (HR): 2.36, 95% confidence interval (CI) 1.52-3.67 and HR: 1.68, 95% CI 1.07-2.63, respectively]. CONCLUSIONS: The intervention did not decrease the risk of BCRL, and axillary dissection and obesity were the risk factors of BCRL. TRIAL REGISTRATION NUMBER: UMIN000020595 at UMIN Clinical Trial Registry.

Baseline gut microbiota as a predictive marker for the efficacy of neoadjuvant chemotherapy in patients with early breast cancer: a multicenter prospective cohort study in the Setouchi Breast Project-14.

PURPOSE: Various studies have demonstrated the causal relationship between gut microbiota and efficacy of chemotherapy; however, the impact of gut microbiota on breast cancer has not been fully elucidated. This study aimed to evaluate the associations between the gut microbiota before neoadjuvant chemotherapy and its consequent efficacy in breast cancer. METHODS: This prospective observational study included patients who received neoadjuvant chemotherapy for primary early breast cancer at eight institutions between October 1, 2019, and March 31, 2022. We performed 16S rRNA analysis of fecal samples and α and ß diversity analyses of the gut microbiota. The primary endpoint was the association between the gut microbiota and pathological complete response (pCR) to neoadjuvant chemotherapy. RESULTS: Among the 183 patients, the pCR rate after neoadjuvant chemotherapy was 36.1% in all patients and 12.9% (9/70), 69.5% (41/59), and 29.6% (16/54) in those with the luminal, human epidermal growth factor receptor 2, and triple-negative types, respectively. The α diversity of the gut microbiota did not significantly differ between patients with pCR and those without pCR. Among the gut microbiota, two species (Victivallales, P = 0.001 and Anaerolineales, P = 0.001) were associated with pCR, and one (Gemellales, P = 0.002) was associated with non-pCR. CONCLUSION: Three species in the gut microbiota had potential associations with neoadjuvant chemotherapy efficacy, but the diversity of the gut microbiota was not associated with response to chemotherapy. Further research is needed to validate our findings.

Lung Oligometastasis of Breast Cancer: Prospective Cohort Study of Treatment Strategies (SBP-06).

While local treatment of metastases is considered to be unrelated to prognosis, previous studies have suggested that local treatment of isolated lung metastases may have positive prognostic impact. We designed this prospective cohort study to investigate the clinical situation and its outcomes. We enrolled patients with fewer than 3 lung nodules suspected of being oligometastases after curative breast cancer surgery. Treatments, including local and systemic therapy, were selected by the physician and patient in consultation. The primary outcome was overall survival (OS); secondary outcomes were the efficacy and the safety of the surgery for lung oligometastases. Between May 2015 and May 2019, 14 patients were enrolled. Resection of lung nodules (metastasectomy) was performed in 11 (78.6%) of 14 patients, and one of these cases was diagnosed as primary lung cancer. Metastasectomies were all performed employing video-assisted thoracic surgery (VATS) without perioperative complications. Systemic therapies were administered to all patients except one. The respective 3-year and 5-year OS rates of patients with lung oligometastases were 91.6% and 81.5%, respectively. Progression occurred in 6 patients: 3 of the 10 with metastasectomy and all 3 without this surgical procedure. Lung metastasectomy was worthwhile as a diagnostic evaluation and may provide long-term benefit in some patients.

Pilot trial of an electronic patient-reported outcome monitoring system in patients with metastatic breast cancer undergoing chemotherapy.

BACKGROUND: Electronic patient-reported outcomes monitoring (ePROM) is a useful communication tool for patients and healthcare providers in cancer chemotherapy. In this study, we examined the feasibility of our newly developed ePROM system, which we refer to as "Hibilog". METHODS: An ePROM app was developed by extracting 18 items from the Patient-Reported Outcome-Common Terminology Criteria for Adverse Events (PRO-CTCAE). Symptom monitoring was conducted every two weeks for patients with metastatic breast cancer undergoing chemotherapy. The primary outcome was the response rate to the ePROM system. The secondary outcomes were response time, item missing rate, and distribution of responses for each symptom. RESULTS: A total of 71 cases (mean age 52.6 years) were analyzed. Performance status was 0 in 76% of the cases and 1 or higher in 24%. First-line treatment was being administered in 30% of cases, second-line treatment in 17%, and third-line or higher treatment in 53%. The response rate to the ePROM system from registration to week 40 remained high at around 80%, indicating good compliance. The average response time was 5.5 min and the missing rate for each item was below 0.4%. Among 1,093 responses, the top 3 symptoms causing interference with daily life were Fatigue (63%), Numbness and tingling (48%), and General pain (46%). CONCLUSION: Our developed ePROM system was able to capture symptoms accurately in patients with metastatic breast cancer undergoing chemotherapy while maintaining a high response compliance.

Long-Term Physical Activity and Body Composition After Exercise and Educational Programs for Breast Cancer: A Randomized Controlled Trial From the Setouchi Breast Project-10.

BACKGROUND: It is unclear what interventions can sustain long-term higher physical activity (PA) to improve breast cancer outcomes. Thus, this study aimed to evaluate the long-term effects of interventions on PA after breast cancer treatment. METHODS: This was a prospective randomized controlled trial for patients with stage 0 to III breast cancer evaluating the efficacy of exercise and educational programs on long-term PA compared with usual care. The primary endpoint was proportion of patients with recreational PA (RPA) ≥5 metabolic equivalents (METs)/week at 1 year after registration. RESULTS: From March 16, 2016, to March 15, 2020, breast cancer patients were registered in the control (n = 120), education (n = 121), or exercise (n = 115) group. There were no significant differences in proportion of RPA ≥5 METs/week at 1 year between the exercise and control groups (54% and 53%, P = .492) and between the education and control groups (62% and 53%, P = .126). Significant difference in reductions from baseline at 1 year were noted on body weight (P = .0083), BMI (P = .0034), and body fat percentage (P = .0027) between education and control groups. Similarly, the exercise group showed significant difference in reduction in body fat percentage (P = .0038) compared to control group. CONCLUSION: Although there were no significant effects on RPA 1 year after exercise and educational programs for breast cancer survivors, both interventions reduced body composition. Future studies on PA should investigate appropriate interventions to improve overall survival.

Systemic immunity markers are associated with clinical outcomes of atezolizumab treatment in patients with triple-negative advanced breast cancer: a retrospective multicenter observational study.

Immune checkpoint inhibitors (ICI) are reportedly efficacious against triple-negative breast cancer (TNBC) and are now recommended as first-line therapy. Systemic immunity markers, the absolute lymphocyte count (ALC) and the neutrophil-to-lymphocyte ratio (NLR), have been identified as predict ICI efficacy in patients with various cancers. We retrospectively enrolled 36 TNBC patients who received atezolizumab treatment between September 2019 and May 2021 at eight Japanese medical institutions. We evaluated systemic immunity markers, including dynamic changes in these markers, as predictors of survival benefit derived from atezolizumab treatment. Median time-to-treatment failure (TTF) and overall survival (OS) were 116 days and "not reached", respectively. Patients with low NLR at baseline and decreased NLR at the start of the second cycle (SO2nd) had significantly longer OS than those with high NLR at baseline and increased NLR (SO2nd) (log-rank P < 0.001 and log-rank P = 0.049, respectively). Multivariate analyses identified high ALC at baseline and decreased NLR (SO2nd) as independent predictive markers for longer TTF (P = 0.043 and P = 0.002, respectively), and low NLR at baseline and decreased NLR (SO2nd) as independent predictive markers for longer OS (P < 0.001 and P = 0.013, respectively). The safety profile was consistent with those of previous trials. This retrospective multicenter observational study showed the clinical efficacy and safety of atezolizumab treatment. Furthermore, systemic immunity markers, including their dynamic changes, were found to be associated with clinical outcomes of atezolizumab treatment in patients with advanced or metastatic TNBC.

Development and validation of a symptom illustration scale from the patient-reported outcome common terminology criteria for adverse events for patients with breast cancer.

PURPOSE: Emojis are commonly used for daily communication and may be useful in assessing patient-reported outcomes (PROs) in breast cancer. The purpose of this study is to develop and validate a Symptom Illustration Scale (SIS) as a new PRO measurement. METHODS: Eighteen original SIS items were developed from the PRO-CTCAE. In cohort one, the SIS validity and reliability were examined in patients with breast cancer, using a semi-structured five-question survey to investigate content validity. PROs with PRO-CTCAE and SIS were examined twice to determine criteria validity and test-retest reliability. In cohort two, the responsiveness of the scales were examined in patients treated with anthracycline, docetaxel, paclitaxel, and endocrine therapy. PROs with PRO-CTCAE and SIS were investigated two or three times, depending on the therapy. RESULTS: Patients were enrolled from August 2019 to October 2020. In cohort one (n = 70), most patients had no difficulties with the SIS, but 16 patients indicated that it was difficult to understand severities in the SIS. For criterion validity, Spearman rank correlation coefficients (rs) between PRO-CTCAE and SIS items were ≥ 0.41, except for "Decreased appetite." For test-retest reliability, κ coefficients of the SIS were ≥ 0.41 for 16/18 items (88.9%). Response time was significantly shorter for the SIS than for PRO-CTCAE (p < 0.001). In cohort two (n = 106), score changes between PRO-CTCAE and SIS for relevant symptoms all had correlations with rs ≥ 0.41. CONCLUSION: An original SIS from the PRO-CTCAE for patients with breast cancer were verified the validity, reliability, and responsiveness. Further studies to improve and validate the SIS are needed.

Impact of Immediate Breast Reconstruction on Survival of Breast Cancer Patients: A Single-Center Observational Study.

Although immediate breast reconstruction following mastectomy has become increasingly common, its oncological safety has been debated. We enrolled patients with breast cancer who underwent surgery at Okayama University Hospital between 2007 and 2013. The primary outcome was relapse-free survival (RFS). Secondary outcomes were overall survival and the duration from the surgery to the initiation of adjuvant chemotherapy. We divided into immediate breast reconstruction, mastectomy alone, and breast conservative surgery groups. Outcomes were compared using Cox's regression analysis. A total of 614 patients were included (reconstruction: 125, mastectomy: 128, breast conservative surgery: 361). The median follow-up duration was 79.0±31.9 months. The immediate-reconstruction patients were younger, had more lymph node metastases, and more often received postoperative chemotherapy. The RFS was better after the breast conservative surgery compared to after reconstruction (hazard ratio 0.33, 95% confidence interval: 0.144-0.763). The proportion of local recurrence was highest in the reconstruction group. No patients in the reconstruction group underwent postoperative radiation therapy. However, reconstruction did not affect overall survival or the time to the initiation of adjuvant chemotherapy. Surgeons should explain the risks of breast reconstruction to their patients preoperatively. Careful long-term follow-up is required after such procedures.

An observational study of the impact of immediate breast reconstruction on perioperative inflammatory cytokines.

PURPOSE: Perioperative inflammatory cytokines may be related to cancer proliferation, although few studies have investigated this issue in patients undergoing breast reconstruction surgery. METHODS: We conducted a prospective study of patients scheduled for mastectomy only, mastectomy plus deep inferior epigastric perforator flap reconstruction (DIEP), or mastectomy plus tissue expander reconstruction (TE), with or without axial dissection (Ax), for primary breast cancer. Blood samples were collected for analysis of serum IL-6 and VEGF preoperatively, then within 24 h postoperatively (POD 1), and 4-6 days postoperatively (POD 4-6). We investigated the difference in serum cytokine levels over time for each surgical procedure and the difference in serum cytokine levels among the procedures at the three measurement time points. RESULTS: There were 120 patients included in the final analysis. Serum IL-6 was significantly higher than the preoperative level on POD 1 in patients who underwent mastectomy only, DIEP, or TE and Ax (+), with higher values persisting on POD 4-6 except in those who underwent DIEP. IL-6 was significantly higher after DIEP than after mastectomy only on POD 1, but no differences were observed at POD 4-6. VEGF did not differ significantly among the surgical procedures at any time. CONCLUSIONS: The increase in IL-6 was short term and immediate breast reconstruction is considered a safe procedure.

Safety and Efficacy of a Well-Fitting Brassiere after Breast Reconstruction: A Qualitative Study.

The importance of a well-fitted, comfortable brassiere to overall quality of life after breast reconstruction has not been evaluated. Our aim was to determine the impact of a semi-customized brassiere on patients' health-related quality of life after breast reconstruction. The subjects were prospective patients with mastectomy who were to undergo immediate or delayed breast reconstruction at our hospital. After surgery, a professional bra fitter sized each patient for a semi-customized brassiere and provided follow-up consultations. A self-reported questionnaire on breast aesthetics, postoperative pain, and satisfaction was used to assess the primary outcomes. Data were prospectively collected at baseline (before surgery) and at 1, 3, 6, and 12 months after surgery and analyzed. Forty-six patients (50 breasts) were included in the analysis. Consistent wearing of the brassiere reduced pain (p<0.05), with good overall satisfaction (p<0.001). Aesthetic scores on breast shape and size were higher with than without the custom brassiere at 3 months (p=0.02) and 6 months (p=0.03) after surgery. Wearing the brassiere reduced anxiety at all time points of measurement. A well-fitting brassiere ensured safety and provided a high degree of satisfaction without anxiety for patients after breast reconstruction.

Predictive value of immune genomic signatures from breast cancer cohorts containing data for both response to neoadjuvant chemotherapy and prognosis after surgery.

BACKGROUND: Previous studies of immune genomic signatures (IGSs) in breast cancer have attempted to predict the response to chemotherapy or prognosis and were performed using different patient cohorts. The purpose of this study was to evaluate the predictive functions of various IGSs using the same patient cohort that included data for response to chemotherapy as well as the prognosis after surgery. METHODS: We applied five previously described IGS models in a public dataset of 508 breast cancer patients treated with neoadjuvant chemotherapy. The prognostic and predictive values of each model were evaluated, and their correlations were compared. RESULTS: We observed a high proportion of expression concordance among the IGS models (r: 0.56-1). Higher scores of IGSs were detected in aggressive breast cancer subtypes (basal and HER2-enriched) (P < 0.001). Four of the five IGSs could predict chemotherapy responses and two could predict 5-year relapse-free survival in cases with hormone receptor-positive (HR +) tumors. However, the models showed no significant differences in their predictive abilities for hormone receptor-negative (HR-) tumors. CONCLUSIONS: IGSs are, to some extent, useful for predicting prognosis and chemotherapy response; moreover, they show substantial agreement for specific breast cancer subtypes. However, it is necessary to identify more compelling biomarkers for both prognosis and response to chemotherapy in HR- and HER2 + cases.

Association of Genetic Polymorphism with Taxane-induced Peripheral Neuropathy: Sub-analysis of a Randomized Phase II Study to Determine the Optimal Dose of 3-week Cycle Nab-Paclitaxel in Metastatic Breast Cancer Patients.

Chemotherapy-induced peripheral neuropathy (CIPN) is an important clinical challenge that threatens patients' quality of life. This sub-study of the ABROAD trial investigated the influence of single nucleotide polymorphisms (SNPs) on CIPN, using genotype data from a randomized study to determine the optimal dose of a 3-week-cycle regimen of nab-paclitaxel (q3w nab-PTX) in patients with metastatic breast cancer (MBC). Patients with HER2-negative MBC were randomly assigned to three doses of q3w nab-PTX (SD: 260 mg/m2 vs. MD: 220 mg/m2 vs. LD: 180 mg/m2). Five SNPs (EPHA4-rs17348202, EPHA5-rs7349683, EPHA6-rs301927, LIMK2-rs5749248, and XKR4-rs4737264) were analyzed based on the results of a previous genome-wide association study. Per-allele SNP associations were assessed by a Cox regression to model the cumulative dose of nab-PTX up to the onset of severe or worsening sensory neuropathy. A total of 141 patients were enrolled in the parent study; 91(65%) were included in this sub-study. Worsening of CIPN was significantly greater in the cases with XKR4 AC compared to those with a homozygote AA (HR 1.86, 95%CI: 1.00001-3.46, p=0.049). There was no significant correlation of CIPN with any other SNP. A multivariate analysis showed that the cumulative dose of nab-PTX was most strongly correlated with CIPN (p<0.01).

Gene Expression Profiling between Patient Groups with High and Low Ki67 Levels after Short-term Preoperative Aromatase Inhibitor Treatment for Breast Cancer.

According to a recent report, a low Ki67 level after short-term preoperative hormone therapy (post-Ki67) might suggest a more favorable prognosis compared with a high post-Ki67 level in patients with hormone receptorpositive/human epidermal growth factor 2-negative (HR+/HER2-) breast cancer with high levels of Ki67. This study aimed to evaluate the pre-treatment genetic differences between these two patient groups. Forty-five luminal B-like patients were stratified into two groups, namely, a group with high (H→H) and one with low (H→L) Ki67 levels after short-term preoperative aromatase inhibitor (AI) treatment. We compared pre-treatment gene expression profiles between the two groups. In gene level analysis, there was no significant difference between the two groups by the class comparison test. In pathway analysis, five metabolism-related gene sets were significantly upregulated in the H→L group (p≤0.05). In the search for novel targets, five genes (PARP, BRCA2, FLT4, CDK6, and PDCD1LG2) showed significantly higher expression in the H→H group (p≤0.05). Several metabolism-related pathways were associated with sensitivity to AI. In the future, it will be necessary to seek out new therapeutic strategies for the poor prognostic group with high post-Ki67.

Evaluation of a novel medical device for pegfilgrastim administration.

Pegfilgrastim, a pegylated form of granulocyte colony-stimulating factor, has reduced the risk of developing febrile neutropenia, which is associated with an increase in severe infection and prolonged hospitalization. However, pegfilgrastim administration requires that patients visit hospital following cancer chemotherapy, thus imposing a burden on patients and those around them. An on-body injector (OBI), which automatically administers pegfilgrastim about 27 hours after chemotherapy, was used in this study. The OBI, which consists of a main pump unit and infusion set, is a drug delivery device designed to be attached to the patient's body, with a timer-controlled dosing function. This study was conducted in breast cancer patients to evaluate the safety of pegfilgrastim administered subcutaneously via the OBI. The study period consisted of screening and treatment observation periods involving four cycles of neoadjuvant or adjuvant chemotherapy with docetaxel plus cyclophosphamide. One 3.6-mg pegfilgrastim dose was administered subcutaneously via OBI during each cycle of chemotherapy. The study enrolled 35 patients, and no serious adverse events or febrile neutropenia occurred. Administration of pegfilgrastim was successfully completed at all times when the OBI was attached to the patient, and no safety concerns associated with OBI function arose. For outpatients requiring pegfilgrastim following cancer chemotherapy, the use of an OBI was considered to be a safe option to reduce the need for outpatient visits that restrict their activities of daily living.

YES1 as a Therapeutic Target for HER2-Positive Breast Cancer after Trastuzumab and Trastuzumab-Emtansine (T-DM1) Resistance Development.

Trastuzumab-emtansine (T-DM1) is a therapeutic agent molecularly targeting human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC), and it is especially effective for MBC with resistance to trastuzumab. Although several reports have described T-DM1 resistance, few have examined the mechanism underlying T-DM1 resistance after the development of acquired resistance to trastuzumab. We previously reported that YES1, a member of the Src family, plays an important role in acquired resistance to trastuzumab in HER2-amplified breast cancer cells. We newly established a trastuzumab/T-DM1-dual-resistant cell line and analyzed the resistance mechanisms in this cell line. At first, the T-DM1 effectively inhibited the YES1-amplified trastuzumab-resistant cell line, but resistance to T-DM1 gradually developed. YES1 amplification was further enhanced after acquired resistance to T-DM1 became apparent, and the knockdown of the YES1 or the administration of the Src inhibitor dasatinib restored sensitivity to T-DM1. Our results indicate that YES1 is also strongly associated with T-DM1 resistance after the development of acquired resistance to trastuzumab, and the continuous inhibition of YES1 is important for overcoming resistance to T-DM1.

Optimizing the timing of 3.6 mg Pegfilgrastim Administration for Dose-Dense Chemotherapy in Japanese Patients with Breast Cancer.

Perioperative dose-dense chemotherapy (DDCT) with pegfilgrastim (Peg) prophylaxis is a standard treatment for high-risk breast cancer. We explored the optimal timing of administration of 3.6 mg Peg, the dose approved in Japan. In the phase II feasibility study of DDCT (adriamycin+cyclophosphamide or epirubicin+cyclophosphamide followed by paclitaxel) for breast cancer, we investigated the feasibility, safety, neutrophil transition, and optimal timing of Peg treatment by administering Peg at days 2, 3, and 4 post-chemotherapy (P2, P3, and P4 groups, respectively). Among the 52 women enrolled, 13 were aged > 60 years. The anthracycline sequence was administered to P2 (n=33), P3 (n=5), and P4 (n=14) patients, and the taxane sequence to P2 (n=38) and P3 (n=6) patients. Both sequences showed no interaction between Peg administration timing and treatment discontinuation, treatment delay, or dose reduction. However, the relative dose intensity (RDI) was significantly different among the groups. The neutrophil count transition differed significantly among the groups receiving the anthracycline sequence. However, the neutrophil count remained in the appropriate range for both sequences in the P2 group. The timing of Peg administration did not substantially affect the feasibility or safety of DDCT. Postoperative day 2 might be the optimal timing for DDCT.

Protocol for a multicentre, prospective, cohort study to investigate patient satisfaction and quality of life after immediate breast reconstruction in Japan: the SAQLA study.

INTRODUCTION: The aim of breast reconstruction (BR) is to improve patients' health-related quality of life (HRQOL). Therefore, measuring patient-reported outcomes (PROs) would clarify the value and impact of BR on a patient's life and thus would provide evidence-based information to help decision-making. The Satisfaction and Quality of Life After Immediate Breast Reconstruction study aimed to investigate satisfaction and HRQOL in Japanese patients with breast cancer who undergo immediate breast reconstruction (IBR). METHODS AND ANALYSIS: This ongoing prospective, observational multicentre study will assess 406 patients who had unilateral breast cancer and underwent mastectomy and IBR, and were recruited from April 2018 to July 2019. All participants were recruited from seven hospitals: Okayama University Hospital, Iwate Medical University Hospital, The Cancer Institute Hospital of Japanese Foundation for Cancer Research, Showa University Hospital, University of Tsukuba Hospital, Osaka University Hospital and Yokohama City University Medical Center. The patients will be followed up for 36 months postoperatively. The primary endpoint of this study will be the time-dependent changes in BREAST-Q satisfaction with breast subscale scores for 12 months after reconstructive surgery, which will be collected via an electronic PRO system. ETHICS AND DISSEMINATION: This study will be performed in accordance with the Ethical Guidelines for Medical and Health Research Involving Human Subjects published by Japan's Ministry of Education, Science and Technology and the Ministry of Health, Labour and Welfare, the modified Act on the Protection of Personal Information and the Declaration of Helsinki. This study protocol was approved by the institutional ethics committee at the Okayama University Graduate School of Medicine, Dentistry, on 2 February 2018 (1801-039) and all other participating sites. The findings of this trial will be submitted to an international peer-reviewed journal. TRIAL REGISTRATION NUMBER: UMIN000032177.

Effect of isoflavones on breast cancer cell development and their impact on breast cancer treatments.

PURPOSE: Epidemiological studies have suggested that intake of soy isoflavones is associated with a reduced risk of development of breast cancer and an improved prognosis in patients with breast cancer. In addition, basic research has demonstrated the antitumor effects of these compounds on breast cancer cell lines. However, the detailed effects of the intake of equol, which is one of the metabolites of the soy isoflavones, are yet to be clarified on the risk of development and recurrence of breast cancer and its interactions with drugs used for treating breast cancer. This study aimed to determine the antitumor effects of equol and investigate the impact of adding equol to therapeutic agents for breast cancer using breast cancer cell lines. METHODS: We examined the antitumor effect of equol on breast cancer cell lines using MTS assay. We also studied the combined effect of equol and the existing hormonal or chemotherapeutic agents using combination index. We evaluated the expressions of the related proteins by Western blot analysis and correlated the findings with the antitumor effect. RESULTS: Equol showed bi-phasic protumor and antitumor effects; at a low concentration, it promoted the tumor growth in hormone receptor-positive cell lines, whereas antitumor effects were generally observed when an excessive amount of dose unexpected in the blood and the tissue was administered. When used with tamoxifen, equol might have some antagonistic effect, although it depends on equol concentration and the type of cancer cells. CONCLUSIONS: We confirmed that equol has dual action, specifically a tumor growth-promoting effect and an antitumor effect. Although the results suggested that equol might exert an antagonistic effect against tamoxifen depending on the concentration, equol did not exert an antagonistic effect on other therapeutic agents.

A Multicenter Study of Docetaxel at a Dose of 100 mg/m2 in Japanese Patients with Advanced or Recurrent Breast Cancer.

Objective This study examined the pharmacokinetics, safety and anti-tumor activity of docetaxel at a dose of 100 mg/m2 in Japanese patients with advanced or recurrent breast cancer. Methods Japanese patients with advanced or recurrent breast cancer received docetaxel at a dose of 100 mg/m2 intravenously every three weeks. The pharmacokinetics were assessed during the first cycle. The patients were allowed to receive supportive care drugs based on the indications and dosages in Japan. Results Six eligible patients aged 39-65 years old and 27 treatment cycles were analyzed. All patients experienced one or more adverse events (AEs). The common AEs were neutropenia, thrombocytopenia, alopecia, rash, diarrhea, neuropathy (sensory), fatigue, nausea, fever, hypoalbuminemia, alanine transaminase (ALT) increased, constipation, and taste alteration. Grade 3 or 4 AEs included neutropenia, leukopenia, anemia, lymphopenia, decreased appetite, γ-glutamyl transpeptidase (GTP) increased, aspartate transaminase (AST) increased, ALT increased, hypertension and cellulitis which were all reversible. There were no cases of febrile neutropenia, serious AEs or deaths. The median number of cycles was six. Dose reductions were not observed and most cycles were administered at their intended doses. No complete response and three partial responses were observed in four assessable patients with evaluable lesions. The maximum concentration and area under the blood concentration-time curve were 3,417.5 ng/mL and 4.35 µg・hr/mL (mean), respectively. Conclusion Docetaxel at a dose of 100 mg/m2 was tolerable with acceptable safety profiles and effective for Japanese patients with advanced or recurrent breast cancer with appropriate supportive therapies, and pharmacokinetic (PK) profiles which corresponded approximately with the findings of previous clinical studies.

Relationships of physical and breast cancer phenotypes with three single-nucleotide polymorphisms (rs2046210, rs3757318, and rs3803662) associated with breast cancer risk in Japanese women.

BACKGROUND: Recent genome-wide association studies have shown that many single-nucleotide polymorphisms (SNPs) are associated with breast cancer risk. However, it is often unclear how these SNPs are related to breast cancer. Analysis of associations between SNPs and phenotypes may be important for determining mechanisms of action, including carcinogenesis. METHODS: In previous case-control studies, we found three SNPs (rs2046210, rs3757318, and rs3573318) associated with breast cancer risk in Japanese women. Among these SNPs, two (rs2046210 and rs3757318) are located at 6q25.1, in proximity to the estrogen receptor 1 gene (ESR1). Using data from these studies, we examined associations between factors related to breast cancer risk, such as height, weight, and breast density, and the three SNPs in cases and controls. We also investigated whether the SNPs correlated with breast cancer features, such as estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor type-2 (HER2) status, and clinical stage. RESULTS: There was a significant difference in mean height between risk and non-risk allele carriers for rs2046210 (156.0 ± 5.8 vs. 154.3 ± 5.5 cm, p = 0.002), and rs3757318 (155.8 ± 5.7 vs. 154.7 ± 5.6 cm, p = 0.035) in cases, but no significant associations between height and these SNPs in controls. There was also a significant difference in breast density between risk and non-risk allele carriers for rs2046210 (p = 0.040) and rs3757318 (p = 0.044) in cases. rs2046210 and rs3757318 risk allele carriers tended to have higher breast density in all subjects and in controls. In cases, rs3757318 risk allele carriers were also significantly more likely to be ER-negative compared to non-risk allele carriers (ER-positive rate: 77% vs. 84%, p = 0.036). CONCLUSIONS: SNPs rs2046210 and rs3757318, which are associated with breast cancer risk in Japanese women, were significantly associated with height and high breast density, and this association was particularly strong in those with breast cancer. These findings suggest that SNPs in the ESR1 gene region affect phenotypes such as height and breast density.