Relationship Between Clinics Offering Telemedicine and Population Density in Japan: An Ecological Study.

Background: The number of clinics offering telemedicine in Japan has been increasing. Regional characteristics such as population density and the number of physicians may be associated with the provision of telemedicine. This study investigated the relationship between clinics offering telemedicine and such regional characteristics for each prefecture in Japan. Methods: Data were collected from publicly available information that included the percentage of clinics offering telemedicine (real-time synchronous type) among all clinics (in 2022), population density, and the number of physicians for each of Japan's 47 prefectures. An ecological study was carried out to determine the correlation between the percentage of clinics offering telemedicine and regional characteristics for each prefecture, and Pearson correlation analysis and multiple regression analysis adjusted for regional characteristics were performed. Results: The min-max and mean levels were, respectively, 3.4-39.2% and 15.6% of clinics offering telemedicine, 66.6-6402.6 and 657.1 people per square kilometer of population density, and 185.2-356.7 and 274.0 physicians per 100,000 people. Geographically, the northeastern regions appeared to show a high percentage of clinics offering telemedicine relative to the southwestern regions. There was a significant negative correlation between the percentage of clinics offering telemedicine and population density (r = -0.31, p < 0.05; ß = -0.31, p < 0.05). Discussion: The negative relationship of the provision of telemedicine in clinics with population density throughout Japan might be a reflection to ensure residents' access to clinics in less populated areas. Although further detailed studies are needed to confirm this, population density might be a useful measure for considering whether to offer telemedicine in clinics in Japan.

Feasibility of accelerated partial breast irradiation with strut-adjusted volume implant brachytherapy in Japan focusing on dosimetry and acute toxicity: a Japanese multi-institutional prospective study.

BACKGROUND: A Japanese multi-institutional prospective study was initiated to investigate the effectiveness and safety of accelerated partial breast irradiation (APBI) using strut-adjusted volume implant (SAVI) brachytherapy, with subjects registered between 2016 and 2021. Herein, we report the preliminary results on the feasibility of this treatment modality in Japan, focusing on the registration process, dosimetry, and acute toxicities. PATIENTS AND METHODS: Primary registration was conducted before breast-conserving surgery (BCS) and the eligibility criteria included the following: age ≥ 40 years, tumor unifocal and unicentric, ≤ 3 cm in diameter, cN0M0, proven ductal, mucinous, tubular, medullary, or lobular carcinoma by needle biopsy. Secondary registration was conducted after BCS had been performed leaving a cavity for device implantation and pathological evaluations, and the eligibility criteria were as follows: negative surgical margin, tumor ≤ 3 cm in diameter on gross pathological examination, histologically confirmed ductal, mucinous, tubular medullary, colloid, or lobular carcinoma, pN0, L0V0, no extensive ductal component, no initiation of chemotherapy within 2 weeks of the brachytherapy APBI planning with SAVI was performed for the patients successfully entered in the study by the secondary registration process, and the treatment was administered at the dose of 34 Gy in 10 fractions administered twice daily. RESULTS: Between 2016 and 2021, 64 women were enrolled in the study through primary registration, of which 19 were excluded from the secondary registration process, and in one, it was deemed impossible to comply with the dose constraints established during treatment planning. After the exclusion of these latter 20 patients, we treated the remaining 44 patients by APBI with SAVI. The dose constraints could be adhered to in all the patients, but re-planning was necessitated in 3 patients because of applicator movement during the treatment period. Grade 2 acute toxicities were observed in 18% of all patients, but more severe acute toxicities than Grade 2 were not observed in any of the patients. CONCLUSION: APBI with SAVI brachytherapy is feasible in Japan from the aspects of compliance with dose constraints and frequency of acute toxicities.

The Relationship between the Distribution of Home Medical Clinics and Home Care Service Offices in Japan.

The increasing number of older people in Japan has led to a need for cooperation between home medical and care services. The collaboration between medical and care provisions in home settings is thus a matter for concern. The present study examines the distribution of and relationship between the number of home medical clinics (HMCs) and home care service offices (HCOs) in Japan. We used national data, detailing the total population, percentage of older adults, and number of HMCs and HCOs. Overall, 23,428 HMCs and 35,612 HCOs were identified nationwide. While the southwestern region of Japan had a high number of HMCs relative to the northeastern region, there was not such a clear difference in the regional distribution of number of HCOs. A linear regression analyses, adjusted for the percentage of older people, revealed a significant positive correlation between the number of HMCs per 10,000 older people and HCOs per 10,000 older people (ß = 0.58, p < 0.001). These findings may allow us to understand advances in cooperation between home medical and care services in Japan.

Copy number alteration is an independent prognostic biomarker in triple-negative breast cancer patients.

BACKGROUND: Next-generation sequencing (NGS) has enabled comprehensive genomic profiling to identify gene alterations that play important roles in cancer biology. However, the clinical significance of these genomic alterations in triple-negative breast cancer (TNBC) patients has not yet been fully elucidated. The aim of this study was to clarify the clinical significance of genomic profiling data, including copy number alterations (CNA) and tumor mutation burden (TMB), in TNBC patients. METHODS: A total of 47 patients with Stage I-III TNBC with genomic profiling of 435 known cancer genes by NGS were enrolled in this study. Disease-free survival (DFS) and overall survival (OS) were evaluated for their association to gene profiling data. RESULTS: CNA-high patients showed significantly worse DFS and OS than CNA-low patients (p = 0.0009, p = 0.0041, respectively). TMB was not associated with DFS or OS in TNBC patients. Patients with TP53 alterations showed a tendency of worse DFS (p = 0.0953) and significantly worse OS (p = 0.0338) compared with patients without TP53 alterations. Multivariable analysis including CNA and other clinicopathological parameters revealed that CNA was an independent prognostic factor for DFS (p = 0.0104) and OS (p = 0.0306). Finally, multivariable analysis also revealed the combination of CNA-high and TP53 alterations is an independent prognostic factor for DFS (p = 0.0005) and OS (p = 0.0023). CONCLUSIONS: We revealed that CNA, but not TMB, is significantly associated with DFS and OS in TNBC patients. The combination of CNA-high and TP53 alterations may be a promising biomarker that can inform beyond standard clinicopathologic factors to identify a subgroup of TNBC patients with significantly worse prognosis.

Diagnostic performance of dedicated breast positron emission tomography.

BACKGROUND: Dedicated breast positron emission tomography (dbPET) has been developed for detecting smaller breast cancer. We investigated the diagnostic performance of dbPET in patients with known breast cancer. METHODS: Eighty-two preoperative patients with breast cancer were included in the study (84 tumours: 11 ductal carcinomas in situ [DCIS], 73 invasive cancers). They underwent mammography (MMG), ultrasonography (US), and contrast-enhanced breast magnetic resonance imaging (MRI) before whole-body PET/MRI (WBPET/MRI) and dbPET. We evaluated the sensitivity of all modalities, and the association between the maximum standard uptake value (SUVmax) level and histopathological features. RESULTS: The sensitivities of MMG, US, MRI, WBPET/MRI and dbPET for all tumours were 81.2% (65/80), 98.8% (83/84), 98.6% (73/74), 86.9% (73/84), and 89.2% (75/84), respectively. For 11 DCIS and 22 small invasive cancers (≤ 2 cm), the sensitivity of dbPET (84.9%) tended to be higher than that of WBPET/MRI (69.7%) (p = 0.095). Seven tumours were detected by dbPET only, but not by WBPET/MRI. Five tumours were detected by only WBPET/MRI because of the blind area of dbPET detector, requiring a wider field of view. After making the mat of dbPET detector thinner, all 22 scanned tumours were depicted. The higher SUVmax of dbPET was significantly related to the negative oestrogen receptor status, higher nuclear grade, and higher Ki67 (p < 0.001). CONCLUSIONS: The sensitivity of dbPET for early breast cancer was higher than that of WBPET/MRI. High SUVmax was related to aggressive features of tumours. Moreover, dbPET can be used for the diagnosis and oncological evaluation of breast cancer.

Identifying ductal carcinoma in situ cases not requiring surgery to exclude postoperative upgrade to invasive ductal carcinoma.

BACKGROUND: Prospective cohort studies are being conducted worldwide to identify a low-grade group of ductal carcinoma in situ (DCIS) that does not require surgery. However, to do this, it is necessary to predict which cases, diagnosed with preoperative DCIS, will be upgraded to invasive ductal carcinoma (IDC) after surgery. METHODS: In this study, we evaluated the frequency of IDC upgrades in patients who were preoperatively diagnosed with DCIS at Showa University using the criteria of ongoing clinical trials. We divided our cases into those that could be enrolled in the ongoing trial and those that could not. Moreover, we evaluated whether CNB, which is allowed only in Japanese clinical trials, is related to the IDC mixture. RESULTS: There were 211 (52.1%) cases that matched the criteria of the U.K. and Netherlands trials, of which 62 (29.4%) were upgraded to IDC. A total of 113 (27.9%) cases met the criteria for clinical trials in Japan and the U.S., 25 (22.1%) of which were upgraded to IDC and 47 (34.6%) which matched when considering biopsy methods. The number of cases upgraded to IDC decreased to four (8.5%). CONCLUSIONS: This study demonstrated that there were a certain number of mixed IDC. We will pay attention to the results of ongoing clinical trials regarding how the presence of this mixed IDC affects the prognosis in non-surgery cases. Careful follow-up is recommended for non-surgical treatment.

Magnetically Guided Localization Using a Guiding-Marker System® and a Handheld Magnetic Probe for Nonpalpable Breast Lesions: A Multicenter Feasibility Study in Japan.

Accurate pre-operative localization of nonpalpable lesions plays a pivotal role in guiding breast-conserving surgery (BCS). In this multicenter feasibility study, nonpalpable breast lesions were localized using a handheld magnetic probe (TAKUMI) and a magnetic marker (Guiding-Marker System®). The magnetic marker was preoperatively placed within the target lesion under ultrasound or stereo-guidance. Additionally, a dye was injected subcutaneously to indicate the extent of the tumor excision. Surgeons checked for the marker within the lesion using a magnetic probe. The magnetic probe could detect the guiding marker and accurately localize the target lesion intraoperatively. All patients with breast cancer underwent wide excision with a safety margin of ≥5 mm. The presence of the guiding-marker within the resected specimen was the primary outcome and the pathological margin status and re-excision rate were the secondary outcomes. Eighty-seven patients with nonpalpable lesions who underwent BCS, from January to March of 2019 and from January to July of 2020, were recruited. The magnetic marker was detected in all resected specimens. The surgical margin was positive only in 5/82 (6.1%) patients; these patients underwent re-excision. This feasibility study demonstrated that the magnetic guiding localization system is useful for the detection and excision of nonpalpable breast lesions.

Meta-analysis of nanoparticle albumin-bound paclitaxel used as neoadjuvant chemotherapy for operable breast cancer based on individual patient data (JBCRG-S01 study).

BACKGROUND: Nanoparticle albumin-bound paclitaxel (nab-PTX), a novel taxane formulation, was developed to avoid cremophor/ethanol-associated toxicities including peripheral neuropathy and hypersensitivity. At least 35 phase II studies using combined nab-PTX and anthracycline in neoadjuvant settings are registered in Japan. We analyzed the efficacy and safety of nab-PTX based on patient characteristics in these studies. METHODS: We conducted a meta-analysis using individual patient data (IPD) to investigate the average efficacy of nab-PTX-containing regimens as neoadjuvant chemotherapy for operable breast cancer. IPD were provided by principal investigators who agreed to participate. The primary endpoint was pathological complete response (pCR) rate of each breast cancer subtype. RESULTS: We analyzed the data of 16 studies involving 753 patients. The overall crude frequencies of pCR (ypT0 ypN0, ypT0/is ypN0, and ypT0/is ypNX) were 18.1, 26.0, and 28.6%, respectively. Specifically, the frequencies were 6.7, 10.2, and 13.4% for luminal (n = 343); 40.5, 63.5, and 68.9% for human epidermal growth factor receptor 2 (HER2)-rich, (n = 74); 21.9, 40.6, and 42.7% for luminal/HER2 (n = 96); and 26.3, 31.5, and 32.3% for triple-negative breast cancers (TNBC) (n = 232). The multivariate analyses indicated that HER2 positivity, TNBC, high Ki-67, high nuclear grade, and weekly nab-PTX administration were significantly associated with the pCR. The proportion of hematological toxicities (neutropenia (39.7%) and leukopenia (22.5%)), peripheral sensory neuropathy (9.7%), myalgia (5.7%), and arthralgia (4.7%) was higher than grade 3 adverse events, but most patients recovered. CONCLUSIONS: Nab-PTX is a safe and acceptable chemotherapeutic agent in neoadjuvant settings, particularly for aggressive cancers. UMIN-CTR#: UMIN000028774.

A Retrospective Analysis of the Relationship Between the Result of BRCA1/2 Genetic Testing and Surgical Method Selection in Japan.

BACKGROUND: We studied the extent of BRCA1/2 genetic testing to help select the surgical approach for patients with breast cancer in Japan remains unclear. PATIENTS AND METHODS: The study subjects were female patients with primary unilateral invasive breast cancer considered as candidates for breast-conserving surgery who underwent preoperative BRCA1/2 genetic testing. A retrospective analysis was performed on the results of BRCA1/2 genetic testing and surgical method selection using national registration data from the Japanese Hereditary Breast and Ovarian Cancer Syndrome Consortium. RESULTS: Our study included 318 female patients. Among these patients, 23.7% of patients with BRCA1/2 mutations and 61.8% of patients without these variants underwent breast-conserving surgery (P < .01). Among the patients with BRCA1/2 mutations, those who chose breast-conserving surgery tended not to undergo risk-reducing salpingo-oophorectomy (P < .05). Among the patients with BRCA1/2 mutations who underwent mastectomy for the affected side, 31.8% received contralateral risk-reducing mastectomy. Patients diagnosed with breast cancer under the age of 50 years were more likely to have contralateral risk-reducing mastectomy than patients over the age 50 years (P < .05). CONCLUSIONS: Patients with BRCA1/2 mutations tend to choose mastectomy. However, it is speculated that the final surgical method selection is made in consideration of not only the test results but also with careful consideration of the patient, taking into account other factors including individual values for risk-reducing surgeries and the age of breast cancer onset.

Risk Factors for Ipsilateral Breast Tumor Recurrence in Triple-Negative or HER2-Positive Breast Cancer Patients Who Achieve a Pathologic Complete Response After Neoadjuvant Chemotherapy.

BACKGROUND: Attention has been focused on attempts to eliminate breast surgery for breast cancer patients who achieve a pathologic complete response after neoadjuvant chemotherapy (NAC). However, there are few data on ipsilateral breast tumor recurrence (IBTR) among patients with triple-negative or epidermal growth factor receptor 2-positive (HER2+) tumors who achieve a pathologic complete response after NAC and breast-conserving treatment. METHODS: Using a multi-institutional retrospective database, this study evaluated the risk factors for IBTR among patients with newly diagnosed stages 1 to 3 breast cancer involving triple-negative or HER2+ tumors who achieved ypT0 after NAC and breast-conserving treatment. RESULTS: During a median follow-up period of 4.8 years (range, 0.1-15.5 years), the 5-year IBTR-free survival rate was 95.5%. The breast cancer subtype was not associated with IBTR-free survival. Patients younger than 40 years at diagnosis had significantly worse IBTR-free survival than those who were 40 years of age or older (5-year IBTR-free survival, 87.7 vs 96.9%; p = 0.002). CONCLUSIONS: This retrospective study demonstrated that age at diagnosis was independently associated with IBTR-free survival. Special caution is needed when clinical trials analyzing omission of breast surgery after NAC are enrolling younger patients (UMIN-CTR No. UMIN000037067).

BRCAness as a prognostic indicator in patients with early breast cancer.

BRCAness is defined as a phenotypic copy of germline BRCA mutations, which describes presence of homologous recombination defects in sporadic cancers. We detected BRCAness by multiplex ligation-dependent probe amplification (MLPA) and explored whether BRCAness can be used as a predictor of prognosis. BRCAness status was classified for total 121 breast cancer patients. Forty-eight patients (39.7%) were identified as BRCAness positive. Tumors of BRCAness were more likely to be hormone receptors negative (95.8% vs. 50.7%, P < 0.001), nuclear grade III (76.1% vs. 48.4%, P = 0.001) and triple-negative breast cancer subtype (91.6% vs. 42.5%, P < 0.001). Five-year disease free survival (DFS) (54.0% vs. 88.0%, P < 0.001) and overall survival (OS) (76.3% vs. 93.1%, P = 0.002) were significantly lower in BRCAness patients. In neoadjuvant chemotherapy subgroup analysis, clinical response rate for taxane-based regimen was significantly lower in BRCAness patients (58.3% vs. 77.8%, P = 0.041). Cox regression multivariate analysis showed that BRCAness was the independent prognostic factor for DFS (HR 2.962, 95%CI 1.184-7.412, P = 0.020), but not for OS (HR 2.681, 95%CI 0.618-11.630, P = 0.188). BRCAness is associated with specific characteristics and may suggest resistance to taxane-based chemotherapy. BRCAness can be used as a negative prognostic indicator for breast cancer.

COVID-19: clinical issues from the Japan Surgical Society.

In this unprecedented COVID-19 pandemic, several key issues must be addressed to ensure safe treatment and prevent rapid spread of the virus and a consequential medical crisis. Careful evaluation of a patient's condition is crucial for deciding the triage plan, based on the status of the disease and comorbidities. As functionality of the medical care system is greatly affected by the environmental situation, the treatment may differ according to the medical and infectious disease circumstances of the institution. Importantly, all medical staff must prevent nosocomial COVID-19 by minimizing the effects of aerosol spread and developing diagnostic and surgical procedures. Polymerase chain reaction (PCR) screening for COVID-19 infection, particularly in asymptomatic patients, should be encouraged as these patients are prone to postoperative respiratory failure. In this article, the Japan Surgical Society addresses the general principles of surgical treatment in relation to COVID-19 infection and advocates preventive measures against viral transmission during this unimaginable COVID-19 pandemic.

BRCA1/BRCA2 mutations in Japanese women with ductal carcinoma in situ.

BACKGROUND: Ductal carcinoma in situ (DCIS) is considered a component of the clinical spectrum of breast cancer even in those with BRCA1/2 mutation. The aim of this study was to report the feature of DCIS raised in Japanese women with BRCA1/2 mutations. METHODS: A total of 325 Japanese women with breast cancer (BC) (with or without invasive cancer) were referred for genetic counseling and underwent genetic testing for mutations in the BRCA1 and BRCA2 genes in Showa University Hospital between December 2011 and August 2016. And 49 of them who were pathologically diagnosed as DCIS were included in this study. Logistic regression models were fit to determine the associations between potential predictive factors and BRCA status. A Cox proportional hazards model is used to predictive value of parameters for Ipsilateral breast tumor recurrence (IBTR) and contralateral breast tumor recurrence (CBTR). RESULTS: (a) Of 325 patients (with or without invasive cancer), 19.1% (62/325) tested positive for BRCA1/BRCA2 mutations. And 18.4% (9/49) was positive for BRCA1/BRCA2 mutations in DCIS, compared with 19.2% (53/276) in IDC (p = 1.000). Among BRCA mutations, 14.5% (9/62) had DCIS compared with nonmutations (15.2%, 40/263). Incidence of DCIS was 3.0% (1/33) of BRCA1 mutations and 27.5% (8/29) of BRCA2 mutation (p = 0.009). (b) Median age of diagnosis in BRCA mutation carriers was 39 years, compared with 46 years in noncarriers. Age, Family history (FH) of BC, FH of first or second BC and total number of relatives with BC diagnosis (DX) has significant difference between BRCA mutation carriers and noncarriers in univariate analysis. In a multivariate logistic model, total relatives with BC DX ≥ 2 (odds ratio [OR], 5.128; 95% confidence interval [CI], 1.266-20.763; p = 0.022), age at diagnosis ≤35 years (OR 0.149, 95% CI 0.023-0.954, p = 0.045) and ER+/HER2+ status (OR 5.034, 95% CI 1.092-23.210, p = 0.038) remained as independent significant predictors for BRCA mutation. Ki67 index (cut off by 14% or 30%) did not differ between BRCA mutation carriers and noncarriers (p = 0.459 and p = 0.651). (c) There was a significant difference in ER-positive tumors among BRCA2 carriers and noncarriers (p = 0.042). Subgroup analysis showed BRCA2 carriers tend to be of higher grade (Grade 2 and 3), more frequently ER+/PR+ (p = 0.041) and lower proliferation (Ki67 index) than noncarriers, whereas differences in nuclear grade and ki67 index were not found significantly in our study. (d) BRCA mutation was not associated with an increased risk of IBTR and CBTR. CONCLUSION: DCIS is equally as prevalent in patients who were BRCA mutation carriers as in high familial-risk women who were noncarriers, but occurs at earlier age. BRCA2 carriers have higher incidence in DCIS than that of BRCA1 carriers, and tend to be higher grade and more frequently ER positive and lower proliferation. Total relatives with BC DX ≥2, age at diagnosis ≤35 years and ER+/HER2+ might be independent predictors for BRCA mutation in Japanese women with DCIS and patients of these risk factors should be recommended to receive genetic counseling and BRCA testing.

Research on Home Care Nursing in Japan Using Geographic Information Systems: A Literature Review.

Given Japan's super-ageing society and its need for developing community-based integrated care system, the role of home care nursing is becoming increasingly important. A central concern in home care nursing is regional/spatial placement of home nursing stations and accessibility for patients. Analysis based on geographic information systems (GIS) may be useful in home care nursing research. We conducted a literature review of home care nursing research based on GIS in Japan. A total of 4 articles were selected following a search of medical literature databases. The first report was published in 2014. Most subjects in the identified studies were older people. Most studies were implemented at a municipal level. Key themes in the identified studies were "placement of specialists and home nursing stations" and "placement of home nursing stations and target patients." Despite the paucity of research, as all identified studies examined the community areas with an aged population, it may point to the need to consider community-based integrated care systems, including home care nursing, in Japan. More GIS-based research on home care nursing is called for.

QOL Evaluation of Nab-Paclitaxel and Docetaxel for Early Breast Cancer.

OBJECTIVE: A previous randomized phase II study showed that neoadjuvant nab-paclitaxel (nab-PTX) 100 mg/m2) was effective and well-tolerated in patients with HER2-negative early-stage breast cancer, compared with docetaxel (DTX). We evaluated patient outcomes in terms of the Functional Assessment of Cancer Therapy-Breast (FACT-B), as a measure of health-related quality of life (HRQoL). MATERIALS AND METHODS: Stage I-III HER2-negative breast cancer patients from the previous study were included. They received either four cycles of nab-PTX (100 mg/m2 days 1/8/15) every 4 weeks, or DTX (75 mg/m2 day 1) every 3 weeks, both followed by four cycles of 5-fluorouracil/epirubicin/cyclophosphamide (FEC). Patients completed a health-related quality-of-life questionnaire at baseline, after one and four cycles of taxanes, before administration of FEC, and after administration of one and four cycles of FEC. RESULTS: Thirty-six eligible patients were enrolled. The baseline characteristics of the two groups were well balanced. FACT-B scores at baseline and after four cycles of taxanes were 115/108 (DTX/nab-PTX) and 99/92, respectively. There were no significant differences between DTX and nab-PTX for FACT-B, FACT-B-Trial Outcome Index (FACT-B-TOI) and FACT-General. FACT-B and FACT-B TOI scores tended to decrease after one cycle and after four cycles of chemotherapy which did not recover to the baseline scores through the end of chemotherapy in each group. CONCLUSION: There were no significant safety differences between nab-PTX and DTX. HRQoL tended to decrease during taxane-based anticancer treatment, with no significant differences between the treatments. We suggest that the HRQoL questionnaire has limited ability to evaluate different chemotherapy schedules. Trial registration UMIN000009855. Nov 20, 2012 registered.

Randomized Multicenter Phase II Trial of Neoadjuvant Therapy Comparing Weekly Nab-paclitaxel Followed by FEC With Docetaxel Followed by FEC in HER2- Early-stage Breast Cancer.

BACKGROUND: Weekly nanoparticle albumin-bound paclitaxel (nab-paclitaxel) demonstrated greater efficacy with less toxicity than docetaxel in metastatic breast cancer. We conducted a randomized phase II to compare these regimens as neoadjuvant chemotherapy for HER2- early-stage breast cancer. PATIENTS AND METHODS: Stage I-III human epidermal growth factor receptor-negative (HER2-) breast cancer patients were included in the present trial and received either docetaxel every 3 weeks or nab-paclitaxel on days 1, 8, and 15 every 28 days for 4 cycles, followed by FEC (5-fluorouracil, epirubicin, cyclophosphamide) every 3 weeks for 4 cycles. The primary endpoint was the pathologic complete response (pCR) rate, defined as ypT0 and ypN0. The secondary endpoints were pCR (ypT0/ypTis and ypN0), the clinical response rate (using the Response Evaluation Criteria In Solid Tumors criteria), histologic effect of treatment (using the Japanese Breast Cancer Society classification), breast conservation rate, and adverse events. RESULTS: A total of 152 eligible patients were enrolled at 6 centers. The baseline characteristics were well balanced. In comparing the 2 regimens (docetaxel/nab-paclitaxel), the pCR rate was 12% and 17% (P = .323). In the Ki67 > 20% group, the pCR rate was greater (24%) for the nab-paclitaxel arm than for the docetaxel arm (16%; P = .432). The most common grade 3/4 adverse event was neutropenia, observed in 40% and 36% of cases in the nab-paclitaxel and docetaxel arms, respectively. The nonhematologic adverse events of any grade were myalgia (34% and 32%), arthralgia (42% and 35%), and peripheral sensory neuropathy (55% and 65%) for the 2 treatment arms. No grade 3/4 peripheral sensory neuropathy was observed in the nab-paclitaxel arm. CONCLUSION: Weekly nab-paclitaxel administered at a dose of 100 mg/m2 showed equivalent efficacy and was well tolerated compared with docetaxel as neoadjuvant therapy. Nab-paclitaxel might be more effective in patients with highly proliferative cancer.

A genome-wide association study identifies three novel genetic markers for response to tamoxifen: A prospective multicenter study.

PURPOSE: Although association studies of genetic variations with the clinical outcomes of breast cancer patients treated with tamoxifen have been reported, genetic factors which could determine individual response to tamoxifen are not fully clarified. We performed a genome-wide association study (GWAS) to identify novel genetic markers for response to tamoxifen. EXPERIMENTAL DESIGN: We prospectively collected 347 blood samples from patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative, invasive breast cancer receiving preoperative tamoxifen monotherapy for 14 to 28 days. We used Ki-67 response in breast cancer tissues after preoperative short-term tamoxifen therapy as a surrogate marker for response to tamoxifen. We performed GWAS and genotype imputation using 275 patients, and an independent set of 72 patients was used for replication study. RESULTS: The combined result of GWAS and the replication study, and subsequent imputation analysis indicated possible association of three loci with Ki-67 response after tamoxifen therapy (rs17198973 on chromosome 4q34.3, rs4577773 on 6q12, and rs7087428 on 10p13, Pcombined = 5.69 x 10-6, 1.64 x 10-5, and 9.77 x 10-6, respectively). When patients were classified into three groups by the scoring system based on the genotypes of the three SNPs, patients with higher scores showed significantly higher after/before ratio of Ki-67 compared to those with lower scores (P = 1.8 x 10-12), suggesting the cumulative effect of the three SNPs. CONCLUSION: We identified three novel loci, which could be associated with clinical response to tamoxifen. These findings provide new insights into personalized hormonal therapy for the patients with breast cancer.

Actionable gene alterations in an Asian population with triple-negative breast cancer.

PURPOSE: It has been suggested that the biological characteristics of breast cancer may differ among different geographic or ethnic populations. Indeed, triple-negative breast cancer (TNBC), the most lethal breast cancer subgroup, has been reported to show a higher incidence in Japan than in the US. However, most genomic studies of these tumors are from Western countries and the genomic landscape of TNBC in an Asian population has not been thoroughly investigated. Here, we sought to elucidate the geographic and ethnic diversity of breast cancer by examining actionable driver alterations in TNBC tumors from Japanese patients and comparing them with The Cancer Genome Atlas (TCGA) database, which gather data primarily from non-Asian patients. MATERIALS AND METHODS: We performed comprehensive genomic profiling, including an analysis of 435 known cancer genes on Japanese TNBC patients (N=53) and compared the results to independent data obtained from TCGA (N=123). RESULTS: Driver alterations were identified in 51 out of 53 Japanese patients (96%). Although the overall alteration spectrum of Japanese patients was similar to that of the TCGA, we found significant differences in the frequencies of alterations in MYC and PTK2. We identified three patients (5.7%) with a high tumor mutation burden, although no microsatellite instability was observed in any of the Japanese patients. Importantly, pathway analysis revealed that 66.0% (35/53) of Japanese patients, as well as 66.7% (82/123) of the TCGA cohort, had alterations in at least one actionable gene targetable by an FDA-approved drug. CONCLUSION: Our study identified actionable driver alterations in Japanese patients with TNBC, revealing new opportunities for targeted therapies in Asian patients.

Digital volumetric measurement of mammographic density and the risk of overlooking cancer in Japanese women.

BACKGROUND: Breast density often affects cancer detection via mammography (MMG). Because of this, additional tests are recommended for women with dense breasts. This study aimed to reveal trends in breast density among Japanese women and determine whether differences in breast density differentially affected the detection of abnormalities via MMG. METHODS: We retrospectively analyzed 397 control women who underwent MMG screening as well as 269 patients who underwent surgery for breast cancer for whom preoperative MMG data were available. VolparaDensity™ (Volpara), a three-dimensional image analysis software with high reproducibility, was used to calculate breast density. Breasts were categorized according to the volumetric density grade (VDG), a measure of the percentage of dense tissue. The associations between age, VDG, and MMG density categories were analyzed. RESULTS: In the control group, 78% of women had dense breasts, while in the breast cancer group, 87% of patients had dense breasts. One of 36 patients with non-dense breasts (2.7%) was classified as category 1 or 2 (C-1 or C-2), indicating that abnormal findings could not be detected by MMG. The proportion of patients with breast cancer who had dense breasts and were classified as C-1 or C-2 was as high as 22.3%. CONCLUSIONS: The proportions of Japanese women with dense breasts were high. In addition, the false-negative rate for women with dense breasts was also high. Owing to this, Japanese women with dense breasts may need to commonly undergo additional tests to ensure detection of breast cancer in the screening MMG.

Significant Effect of Polymorphisms in CYP2D6 on Response to Tamoxifen Therapy for Breast Cancer: A Prospective Multicenter Study.

Purpose: CYP2D6 is the key enzyme responsible for the generation of the potent active metabolite of tamoxifen, "endoxifen." There are still controversial reports questioning the association between CYP2D6 genotype and tamoxifen efficacy. Hence, we performed a prospective multicenter study to evaluate the clinical effect of CYP2D6 genotype on tamoxifen therapy.Experimental Design: We enrolled 279 patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative, invasive breast cancer receiving preoperative tamoxifen monotherapy for 14 to 28 days. Ki-67 response in breast cancer tissues after tamoxifen therapy was used as a surrogate marker for response to tamoxifen. We prospectively investigated the effects of allelic variants of CYP2D6 on Ki-67 response, pathological response, and hot flushes.Results: Ki-67 labeling index in breast cancer tissues significantly decreased after preoperative tamoxifen monotherapy (P = 0.0000000000000013). Moreover, proportion and Allred scores of estrogen receptor-positive cells in breast cancer tissues were significantly associated with Ki-67 response (P = 0.0076 and 0.0023, respectively). Although CYP2D6 variants were not associated with pathologic response nor hot flushes, they showed significant association with Ki-67 response after preoperative tamoxifen therapy (P = 0.018; between two groups, one with at least one wild-type allele and the other without a wild-type allele).Conclusions: This is the first prospective study evaluating the relationship between CYP2D6 variants and Ki-67 response after tamoxifen therapy. Our results suggest that genetic variation in CYP2D6 is a key predictor for the response to tamoxifen in patients with breast cancer. Clin Cancer Res; 23(8); 2019-26. ©2016 AACR.