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.

Phase III study of long-term prognosis of estrogen receptor-positive early breast cancer treated with neoadjuvant endocrine therapy with/without adjuvant chemotherapy.

PURPOSE: Neoadjuvant endocrine therapy (NET) is a treatment option for estrogen receptor-positive (ER+) postmenopausal early breast cancer (EBC). This phase III trial evaluated the prognosis of EBC patients treated with/without chemotherapy (CT) following NET. METHODS: ER+/HER2-, T1c-2, and clinically node-negative EBC patients were enrolled in 2008-2013 and treated with endocrine therapy (ET) in weeks 24-28. All patients, excluding those with progressive disease (PD) during NET or ≥ 4 positive lymph nodes after surgery, were randomized to ET for 4.5-5 years with/without CT. The primary endpoint was disease-free survival (DFS). Secondary endpoints included distant DFS (DDFS), overall survival (OS), and DFS/DDFS/OS according to clinical response to NET. RESULTS: Of 904 patients, 669 were randomized to CT+ET (n = 333) or ET alone (n = 336). The median follow-up was 7.8 years. DFS (CT+ET, 47 events; ET alone, 70 events) and DDFS did not reach the planned numbers of events. Eight-year DFS/DDFS rates were 86%/93% and 83%/92%, respectively. DFS was significantly better in CT+ET than ET alone in subgroups aged < 60 years (P = 0.016), T2 (P = 0.013), or Ki67 > 20% (P = 0.026). Progesterone receptor and histological grade were predictive markers for clinical responses to NET. CONCLUSION: NET may be used as standard treatment for patients with ER+EBC. Although it is difficult to decide whether to administer adjuvant CT based solely on the effect of NET, the response to NET may help to inform this decision. TRIAL REGISTRATION: This study was registered at the UMIN Clinical Trials Registry under UMIN000001090 (registered 20 March 2008).

Gradient Boosted Tree Approaches for Mapping European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 Onto 5-Level Version of EQ-5D Index for Patients With Cancer.

OBJECTIVES: This study aimed to develop direct and response mapping algorithms from the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 onto the 5-level version of EQ-5D index based on the gradient boosted tree (GBT), a promising modern machine learning method. METHODS: We used the Quality of Life Mapping Algorithm for Cancer study data (903 observations from 903 patients) for training GBTs and testing their predictive performance. In the Quality of Life Mapping Algorithm for Cancer study, patients with advanced solid tumor were enrolled, and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and 5-level version of EQ-5D were simultaneously evaluated. The Japanese value set was used for direct mapping, whereas the Japanese and US value sets were used for response mapping. We trained the GBTs in the training data set (80%) with cross-validation and tested the predictive performance measured by the root mean squared error (RMSE), mean absolute error (MAE), and mean error in the test data set (20%). RESULTS: The RMSE and MAE in the test data set were larger in the GBT approaches than in the previously developed regression-based approaches. The mean error in the test data set tended to be smaller in the GBT approaches than in the previously developed regression-based approaches. CONCLUSIONS: The predictive performances in the RMSE and MAE did not improve by the GBT approaches compared with regression approaches. The flexibility of the GBT approaches had the potential to reduce overprediction and underprediction in poor and good health, respectively. Further research is needed to establish the role of machine learning methods in mapping a nonpreference-based measure onto health utility.

Impacts of the preceding cancer-specific health-related quality of life instruments on the responses to the subsequent EQ-5D-5L.

BACKGROUND: In clinical studies, the EQ-5D-5L is often employed with disease-specific health-related quality of life instruments. The questions in the former are more general than the latter; however, it is known that responses to general questions can be influenced by preceding specific questions. Thus, the responses to the EQ-5D-5L have the possibility of being influenced by the preceding disease-specific health-related quality of life instruments. This may lead to bias in the cost-effectiveness analysis results. Therefore, this study aimed to evaluate the impact of the preceding cancer-specific health-related quality of life instruments on the EQ-5D-5L responses. METHODS: We prepared questionnaire booklets containing the EQ-5D-5L, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30, and the Functional Assessment of Cancer Therapy General with different orders. Using a quasi-randomized design, they were distributed to the patients undergoing drug therapy for advanced cancer, who were classified into three groups: Groups 1, 2, and 3 (the EQ-5D-5L placed first, second, and last, respectively). We compared the EQ-5D-5L index and the missingness of EQ-5D-5L among the groups. RESULTS: The mean EQ-5D-5L index was 0.796, 0.760, and 0.789 for groups 1 (n = 300), 2 (n = 306), and 3 (n = 331), respectively. The difference between Groups 2 and 1 was - 0.036 (95% CI - 0.065 to - 0.007; p = 0.015). The proportion of patients with an incomplete EQ-5D-5L was 0.11, 0.11, and 0.05 for Groups 1, 2, and 3, respectively. The difference of the proportions between group 3 and 1 and between 3 and 2 was - 0.06 (95% CI - 0.10 to - 0.02; p = 0.003) and - 0.06 (95% CI - 0.10 to - 0.02; p = 0.003), respectively. CONCLUSIONS: Although the EQ-5D-5L index differed according to the instrument orders, the difference size would not be considerably larger than the minimally important difference. The patients tended to complete the EQ-5D-5L when they were placed at the end of the questionnaire.

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.

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.

Switch maintenance endocrine therapy plus bevacizumab after bevacizumab plus paclitaxel in advanced or metastatic oestrogen receptor-positive, HER2-negative breast cancer (BOOSTER): a randomised, open-label, phase 2 trial.

BACKGROUND: Anticancer treatment regimens typically cause unpleasant side-effects. We aimed to investigate the benefit of switch maintenance endocrine therapy plus bevacizumab after fixed cycles of first-line induction chemotherapy with weekly paclitaxel plus bevacizumab in patients with oestrogen receptor (ER)-positive, HER2-negative advanced or metastatic breast cancer. METHODS: BOOSTER was a prospective, open-label, multicentre, randomised, controlled, phase 2 study done in 53 hospitals in Japan. Eligible patients were women aged 20-75 years, with an Eastern Cooperative Oncology Group performance status of 0-1, who had not received chemotherapy for ER-positive, HER2-negative advanced or metastatic breast cancer. All patients received four to six cycles (in which 4 weeks of treatment constitute one cycle) of weekly paclitaxel plus bevacizumab induction therapy (weekly paclitaxel 90 mg/m2, administered intravenously on days 1, 8, and 15 of each cycle, plus bevacizumab 10 mg/kg administered intravenously on days 1 and 15 of each cycle; first registration). Patients with a complete response, partial response, or stable disease after induction therapy (responders) were then randomly assigned (1:1) using the randomisation enrolment form to either continue weekly paclitaxel plus bevacizumab or switch to maintenance endocrine therapy (an aromatase inhibitor or fulvestrant with or without ovarian-function suppression) plus bevacizumab. Randomisation was stratified by induction therapy period, response to induction therapy, age, history of endocrine therapy, and study site. Patients could receive weekly paclitaxel plus bevacizumab reinduction if they had disease progression with maintenance endocrine therapy plus bevacizumab. The primary endpoint was time to failure of strategy (TFS). Efficacy and safety analyses were done in all treated patients (full analysis set). This study is registered with ClinicalTrials.gov, NCT01989780, and registration and follow-up are closed. FINDINGS: Between Jan 1, 2014, and Dec 31, 2015, we enrolled 160 patients who began weekly paclitaxel plus bevacizumab induction therapy. 125 (78%) patients (responders) were randomly assigned to endocrine therapy plus bevacizumab (n=62; n=61 in the full analysis set) or weekly paclitaxel plus bevacizumab (n=63; n=63 in the full analysis set). Among 61 patients in the switch maintenance endocrine therapy plus bevacizumab group, 32 (52%) were reinitiated on weekly paclitaxel plus bevacizumab. At a median follow-up of 21·3 months (IQR 13·0-28·2), TFS was significantly longer in the endocrine therapy plus bevacizumab group than in the weekly paclitaxel plus bevacizumab group (median 16·8 months [95% CI 12·9-19·0] vs 8·9 months [5·7-13·8]; hazard ratio 0·51 [0·34-0·75]; p=0·0006). The most common grade 3-4 non-haematological adverse events after randomisation were proteinuria (in ten [16%] of 61 patients in the endocrine therapy plus bevacizumab group vs eight [13%] of 63 patients in the weekly paclitaxel plus bevacizumab group), hypertension (six [10%] vs six [10%]), and peripheral neuropathy (one [2%] vs six [10%]). One treatment-related death was reported in the weekly paclitaxel plus bevacizumab group (duodenal ulcer perforation). INTERPRETATION: Switch to maintenance endocrine therapy plus bevacizumab with the possibility of weekly paclitaxel reinduction if needed is an efficacious alternative, with a better safety profile, to continuing weekly paclitaxel plus bevacizumab in patients with ER-positive, HER2-negative advanced or metastatic breast cancer who have responded to induction therapy. FUNDING: Chugai Pharmaceutical. TRANSLATION: For the Japanese translation of the abstract see Supplementary Materials section.

Pertuzumab retreatment for HER2-positive advanced breast cancer: A randomized, open-label phase III study (PRECIOUS).

No standard options existed for human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer that progresses after second-line trastuzumab emtansine therapy before 2020. The purpose of this study was to examine the efficacy of pertuzumab retreatment after disease progression following pertuzumab-containing therapy for HER2-positive locally advanced or metastatic breast cancer for the first time. This randomized, open-label, multicenter phase III trial was undertaken in 93 sites in Japan. Eligible patients with HER2-positive breast cancer who had received pertuzumab, trastuzumab, and chemotherapy as first- and/or second-line therapy were randomly assigned (1:1) to: (i) pertuzumab, trastuzumab, and physician's choice chemotherapy (PTC), or (ii) trastuzumab and physician's choice chemotherapy (TC). The primary end-point was investigator-assessed progression-free survival (PFS). Between August 1, 2015 and December 31, 2018, 219 patients were randomized to PTC (n = 110) or TC (n = 109). Median follow-up was 14.2 months (interquartile range, 9.0-22.2), and median PFS was 5.3 months (95% confidence interval [CI], 4.0-6.6) with PTC and 4.2 months (95% CI, 3.2-4.8) with TC (stratified hazard ratio 0.76 [95% CI upper limit 0.967]; p = 0.022). Progression-free survival was improved by adding pertuzumab in all prespecified subgroups. The PTC arm showed a trend towards better overall survival and duration of response, but similar objective response and health-related quality of life. The incidence of treatment-related adverse events was similar between groups except for diarrhea. Pertuzumab retreatment contributes to disease control for HER2-positive locally advanced or metastatic breast cancer previously treated with pertuzumab-containing regimens.

Association of change in health-related quality of life and treatment discontinuation in metastatic breast cancer: a post hoc, exploratory analysis of two randomized clinical trials.

PURPOSE: Identifying factors associated with treatment alteration (treatment discontinuation and dose reduction) may help to attain the treatment goals for metastatic breast cancer. The value of changes in the quality of life (QOL) in predicting treatment alteration remained unclear. This study aimed to examine the relationship between changes in the QOL and treatment alteration of first-line chemotherapy for metastatic breast cancer. METHODS: We merged data from two randomized clinical trials in Japan, conducted from 2006 to 2017, that included patients who were diagnosed with human epidermal growth factor receptor 2-negative and endocrine treatment-resistant breast cancer, with metastatic disease at presentation or recurrence after surgery. The European Organisation for the Research and Treatment of Cancer Quality of Life Questionnaire Core 30 was used to assess QOL. The association between change in time-dependent QOL (worsening by 10-point or not) and time to treatment alteration was assessed using the Cox regression models controlling for patient characteristics (age, liver metastasis, hormone status, and treatment regimen) and baseline QOL. RESULTS: Worsening physical functioning, global health status, and dyspnea were significantly associated with treatment discontinuation. Worsening role functioning, global health status, and fatigue were significantly associated with dose reduction. The threshold for defining worsening did not have a significant impact on the relationship. CONCLUSION: Changes in QOL are associated with the probability of treatment alteration among metastatic breast cancer patients. Physical functioning, role functioning, global health status, dyspnea, and fatigue should be prioritized for symptom management in patients with metastatic breast cancer.

Minimal important differences of EORTC QLQ-C30 for metastatic breast cancer patients: Results from a randomized clinical trial.

PURPOSE: To establish minimal important differences (MIDs) for the European Organisation for Research and Treatment for Cancer Quality of life Questionnaire core 30 (EORTC QLQ-C30) in patients with metastatic breast cancer. METHODS: The dataset was obtained from the SELECT BC-CONFIRM randomized clinical trial. Anchors obtained from patients (transition items) and clinicians (performance status) were used for anchor-based methods. Anchors obtained through 6 months after starting treatment were used for this analysis. Correlation coefficients of anchor and change in QLQ-C30 and effect size were used to qualify for estimating MIDs. Mean change method and generalized estimating equation were applied to estimate MIDs. Distribution-based methods were used for comparison. RESULTS: We analyzed a dataset of 154 metastatic breast cancer patients. MIDs were estimated in 8 of 15 scales of QLQ-C30. Estimated MIDs for within-group improvement varied from 7 to 15 and those for deterioration varied from - 7 to - 17. Estimated MIDs for between-group improvement varied from 5 to 11 and those for deterioration varied from - 5 to - 8 across QLQ-C30 scales. Patient-reported anchors were more susceptible to early changes in health status than clinician-reported anchors. CONCLUSION: We provided the MIDs of the QLQ-C30 using both patient- and clinicians-reported anchors measured in a randomized trial of Japanese patients with metastatic breast cancer. We recommend patient-reported anchors for anchor-based estimation of MID. Our results can aid patients and clinicians, as well as researchers, in the interpretation of QLQ-C30.

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.

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).

Impact of chemotherapy on cognitive functioning in older patients with HER2-positive breast cancer: a sub-study in the RESPECT trial.

PURPOSE: To investigate whether postoperative adjuvant trastuzumab plus chemotherapy negatively affected cognitive functioning during the post-chemotherapy period compared with trastuzumab monotherapy in older patients with HER2-positive breast cancer. METHODS: In the randomized RESPECT trial, women aged between 70 and 80 years with HER2-positive, stage I to IIIA invasive breast cancer who underwent curative operation were randomly assigned to receive either 1-year trastuzumab monotherapy or 1-year trastuzumab plus chemotherapy. Cognitive functioning was assessed using the Mini-Mental State Examination (MMSE) test at enrollment and 1 and 3 years after initiation of the protocol treatment. The primary outcome was change in the MMSE total score from baseline. Secondary outcomes included prevalence of suspected mild cognitive impairment (MMSE total score < 28) and suspected dementia (MMSE total score < 24). RESULTS: The analytical population consisted of 29 and 26 patients in the trastuzumab monotherapy and trastuzumab plus chemotherapy groups, respectively. The group differences in mean changes of the MMSE total score were 0.6 (95% confidence interval [CI] - 0.3 to 1.6) at 1 year and 0.9 (95% CI - 1.0 to 2.8) at 3 years (P = 0.136 for the group difference pooling the two visits). The prevalence of suspected mild cognitive impairment at 3 years was 41.7% in the trastuzumab monotherapy group and 28.6% in the trastuzumab plus chemotherapy group (P = 0.548). CONCLUSION: This randomized sub-study did not show worse cognitive functioning during the post-chemotherapy period with trastuzumab plus chemotherapy than with trastuzumab monotherapy in older patients with HER2-positive breast cancer. TRIAL REGISTRATION NUMBER: NCT01104935 (first posted April 16, 2010).

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.

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.

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.

Response Shift-Adjusted Treatment Effect on Health-Related Quality of Life in a Randomized Controlled Trial of Taxane Versus S-1 for Metastatic Breast Cancer: Structural Equation Modeling.

OBJECTIVE: We investigated the quantification of the response shift-adjusted treatment effect on quality-of-life (QOL) data in a randomized controlled trial of taxane versus S-1 for patients with metastatic breast cancer (SELECT-BC). METHODS: This study was a secondary data analysis of a previously published trial. The response shift-adjusted treatment effect on health-related QOL (HRQOL) data measured by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) was estimated using structural equation modeling techniques in addition to quantifying the "true" treatment effect. Measurement invariances in the values of the common factor loadings, intercepts, and residual variances between before treatment and at the 3-, 6-, and 12-month visits were considered the response shift effects. RESULTS: In the taxane group, we observed positive recalibration effects for role functioning and positive reprioritization and negative recalibration effects for emotional functioning. The observed change of -4.56 for role functioning comprised +2.26 response shifts and -6.82 "true" change. The observed change of +9.41 for emotional functioning comprised +12.43 response shifts and -1.17 "true" change. In the S-1 group, we observed positive reprioritization and negative recalibration effects for emotional functioning and positive reprioritization effects for social functioning. The observed change of +10.54 for emotional functioning comprised +10.07 response shifts and +0.47 "true" change. The observed change of +2.43 for social functioning comprised +3.50 response shifts and -1.07 "true" change. CONCLUSION: Detailed analysis of the response shift effects will improve the evaluation reliability of observed HRQOL data during clinical trials.

Mapping EORTC QLQ-C30 and FACT-G onto EQ-5D-5L index for patients with cancer.

BACKGROUND: To develop direct and indirect (response) mapping algorithms from the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy General (FACT-G) onto the EQ-5D-5L index. METHODS: We conducted the QOL-MAC study where EQ-5D-5L, EORTC QLQ-C30, and FACT-G were cross-sectionally evaluated in patients receiving drug treatment for solid tumors in Japan. We developed direct and indirect mapping algorithms using 7 regression methods. Direct mapping was based on the Japanese value set. We evaluated the predictive performances based on root mean squared error (RMSE), mean absolute error, and correlation between the observed and predicted EQ-5D-5L indexes. RESULTS: Based on data from 903 and 908 patients for EORTC QLQ-C30 and FACT-G, respectively, we recommend two-part beta regression for direct mapping and ordinal logistic regression for indirect mapping for both EORTC QLQ-C30 and FACT-G. Cross-validated RMSE were 0.101 in the two methods for EORTC QLQ-C30, whereas they were 0.121 in two-part beta regression and 0.120 in ordinal logistic regression for FACT-G. The mean EQ-5D-5L index and cumulative distribution function simulated from the recommended mapping algorithms generally matched with the observed ones except for very good health (both source measures) and poor health (only FACT-G). CONCLUSIONS: The developed mapping algorithms can be used to generate the EQ-5D-5L index from EORTC QLQ-C30 or FACT-G in cost-effectiveness analyses, whose predictive performance would be similar to or better than those of previous algorithms.