Is there disparity between regions and facilities in surgical resident training in Japan? Insights from a national survey.

PURPOSE: This study sought to assess the disparity between regions and facilities in surgical resident training in Japan via a national level needs-assessment. METHODS: A survey was sent to all 909 graduating residents of 2016. Residents trained in the six prefectures with a population of 7 million or more were included in the large prefecture (LP) group. Residents trained in the other 41 prefectures were included in the small prefecture (SP) group. Each group was further divided into a university hospital (UH) group and a non-university hospital (NUH) group. RESULTS: The response rate was 56.3% (n = 512). Excluding nine residents who did not report their prefectures and facilities, surveys from 503 residents were analyzed. The UH group received significantly more years of training. In the SP and UH groups, there were significantly fewer residents who had performed 150 procedures or more under general anesthesia in comparison to the LP and NUH groups, respectively. Self-assessed competencies for several procedures were significantly lower in the SP and UH groups. CONCLUSION: Disparity in surgical resident training was found between regions and facilities in Japan. The surgical residency curriculum in Japan could be improved to address this problem.

Are graduating residents sufficiently competent? Results of a national gap analysis survey of program directors and graduating residents in Japan.

PURPOSE: To evaluate the self-assessed competency of graduating residents (GRs) in Japan upon completion of their residency and to identify the gap between their competency and the competency expected by their program directors (PDs). METHOD: A list of 31 essential surgical procedures was compiled according to the consensus of surgical educators from around the country. A survey with this list was sent to all 909 GRs and their 611 PDs in 2016. The GRs rated their competency to perform these procedures and the PDs were asked to evaluate the expected competency of their GRs using the Zwisch Scale. RESULT: The response rate was 56.3% for the GRs and 76.8% for the PDs. Fewer than half of the GRs who responded felt confident performing ten (32%) of the surgical procedures evaluated. For most procedures, the GRs' self-reported competency was lower than the expectation reported by their PDs. This gap was more than 10% for 13 of the procedures. CONCLUSION: More than half of the GRs in Japan lacked the confidence in their skill to perform one-third of the surgical procedures selected for evaluation in this study. These findings should be used to update the surgical education curriculum in Japan.

PF-05280014 (a trastuzumab biosimilar) plus paclitaxel compared with reference trastuzumab plus paclitaxel for HER2-positive metastatic breast cancer: a randomised, double-blind study.

BACKGROUND: This randomised, double-blind study compared PF-05280014 (a trastuzumab biosimilar) with reference trastuzumab (Herceptin®) sourced from the European Union (trastuzumab-EU), when each was given with paclitaxel as first-line treatment for HER2-positive metastatic breast cancer. METHODS: Between 4 April 2014 and 22 January 2016, 707 participants were randomised 1:1 to receive intravenous PF-05280014 plus paclitaxel (PF-05280014 group; n = 352) or trastuzumab-EU plus paclitaxel (trastuzumab-EU group; n = 355). PF-05280014 or trastuzumab-EU was administered weekly (first dose 4 mg/kg, subsequent doses 2 mg/kg), with the option to change to a 3-weekly regimen (6 mg/kg) from Week 33. Treatment with PF-05280014 or trastuzumab-EU could continue until disease progression. Paclitaxel (starting dose 80 mg/m2) was administered on Days 1, 8 and 15 of 28-day cycles for at least six cycles or until maximal benefit of response. The primary endpoint was objective response rate (ORR), evaluating responses achieved by Week 25 and confirmed by Week 33, based on blinded central radiology review. RESULTS: The risk ratio for ORR was 0.940 (95% CI: 0.842-1.049). The 95% CI fell within the pre-specified equivalence margin of 0.80-1.25. ORR was 62.5% (95% CI: 57.2-67.6%) in the PF-05280014 group and 66.5% (95% CI: 61.3-71.4%) in the trastuzumab-EU group. As of data cut-off on 11 January 2017 (using data up to 378 days post-randomisation), there were no notable differences between groups in progression-free survival (median: 12.16 months in the PF-05280014 group vs. 12.06 months in the trastuzumab-EU group; 1-year rate: 54% vs. 51%) or overall survival (median: not reached in either group; 1-year rate: 89.31% vs. 87.36%). Safety outcomes and immunogenicity were similar between the treatment groups. CONCLUSION: When given as first-line treatment for HER2-positive metastatic breast cancer, PF-05280014 plus paclitaxel demonstrated equivalence to trastuzumab-EU plus paclitaxel in terms of ORR. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01989676.

A snapshot of surgical resident training in Japan: results of a national-level needs assessment survey.

PURPOSE: To evaluate the status of surgical training in Japan through a national-level needs assessment. METHODS: A survey was sent to all 909 graduating residents (GRs) and their 611 program directors (PDs) for the year 2016. A working group of surgical educators from around the country was formed under the education committee of the Japan Surgical Society. The survey items were developed by consensus of this working group. The survey investigated the knowledge and problems of the current curriculum, and the status of the current residency training. RESULTS: The response rates were 56.3% of the GRs and 76.8% of the PDs. Among the participants, 47.6% of the GRs and 29.4% of the PDs believed that the residency curriculum did not match the clinical experience. Over 80% of the GRs and PDs agreed on the importance of training outside of the OR, whereas only 13% of the GRs had received such training regularly. Trainees also reported a lower satisfaction rate about the opportunity to train outside of the OR. CONCLUSION: This national-level needs assessment of surgical training in Japan identified several gaps in the curriculum. These results provide valuable data to assist the ongoing efforts for surgical residency curriculum improvement.

Clinical significance of plasma cell-free DNA mutations in PIK3CA, AKT1, and ESR1 gene according to treatment lines in ER-positive breast cancer.

The somatic activation of PI3K/AKT pathway mutations, PIK3CA and AKT1, and ESR1 mutations in plasma cell-free DNA (cfDNA) has been studied as a non-invasive procedure to quickly assess and monitor disease progression or therapeutic effect in breast cancer (BC) patients, but the clinical significance of these mutations in late treatment lines (TLs) remains unclear. The subjects of this study were a total of 251 plasma samples from 128 estrogen receptor-positive (ER+) BC patients. Of these plasma samples, 133 were from 73 primary BC (PBC) patients, and 118 plasma samples were from 68 metastatic BC (MBC) patients. We developed droplet digital PCR (ddPCR) assays to verify the clinical significance of PIK3CA, AKT1, and ESR1 mutations in these patients. cfDNA PIK3CA mutations were observed in 15.1% of the PBC patients, while a cfDNA AKT1 mutation was observed in 1.4% of patients, and cfDNA ESR1 mutations were observed in 2.7% of patients. Patients with detectable cfDNA PIK3CA mutations were not associated with clinical outcomes. According to the TL, the prevalence of the PIK3CA and ESR1 mutations in cfDNA were lower in early TLs compared with late TLs. In the early TL group, patients with cfDNA PIK3CA mutations had a shorter time to treatment failure (TTF) than patients without mutations (P = 0.035). However, there was no statistically significant difference between patients with or without cfDNA ESR1 mutations. However, in the late TL group, patients with cfDNA ESR1 mutations had a shorter TTF than patients without mutations (P = 0.048). However, there was no statistically significant difference between patients with or without cfDNA PIK3CA mutations. Since the prevalence of cfDNA AKT1 mutation is low in both PBC and MBC patients, the impact of AKT1 mutations on the prognosis remains unclear. We have demonstrated the difference in the clinical significance of the hotspot PIK3CA, AKT1, and ESR1 mutations in cfDNA for each TL in ER+ BC patients.

Therapeutic predictors of neoadjuvant endocrine therapy response in estrogen receptor-positive breast cancer with reference to optimal gene expression profiling.

PURPOSE: Neoadjuvant endocrine therapy (NAET) for estrogen receptor-positive primary breast cancer causes adequate tumor shrinkage, and is expected to be helpful for breast-conserving surgery, but the adaptation criteria, especially in regard to treatment duration, have never been elucidated. Re-visiting past gene expression profiles, we explored the data for specialized pre-therapeutic predictors and validated the results using our in-house clinical cohorts. METHODS: We sorted the genes related to a > 30% tumor volume reduction through NAET from a cDNA microarray data-set of GSE20181, then selected the top 40 genes. We validated these gene expression levels using pre-therapeutic biopsy samples obtained from patients treated with long-term NAET (over 4 months; N = 40). A short-term (2-8 weeks; N = 37) NAET cohort was also validated to clarify whether expression of these genes is also related to a rapid response of Ki67 and PEPI score. RESULTS: In the long-term group, higher expression of KRAS, CUL2, FAM13A, ADCK2, and LILRA2 was significantly associated with tumor shrinkage, and KRAS, MMS19, and IVD were related to lower PEPI score (≤ 3). Meanwhile in the short-term group, none of these genes except CUL2 showed a direct correlation with Ki67 reduction or PEPI score. This suggested that tumor shrinkage by NAET might be induced by response to the hypoxic environment (CUL2, FAM13A, KRAS) and activation of tumor immune system (LILRA2), without involving inhibition of proliferation. CONCLUSION: Expression of specific genes may allow selection of the most responsive patients for maximum tumor shrinkage with NAET.

Lenvatinib: A Promising Molecular Targeted Agent for Multiple Cancers.

Lenvatinib is a small-molecule tyrosine kinase inhibitor that inhibits vascular endothelial growth factor receptor (VEGFR1-3), fibroblast growth factor receptor (FGFR1-4), platelet-derived growth factor receptor α (PDGFRα), stem cell factor receptor (KIT), and rearranged during transfection (RET). These receptors are important for tumor angiogenesis, and lenvatinib inhibits tumor angiogenesis by inhibiting function of these receptors. Phase I trials of lenvatinib were conducted at the same time in Japan, Europe, and the United States, and tumor shrinkage effects were observed in thyroid cancer, endometrial cancer, melanoma, renal cell carcinoma, sarcoma, and colon cancer. Lenvatinib is a promising drug that has shown therapeutic effects against various solid tumors. Adverse events, such as hypertension, proteinuria, diarrhea, and delayed wound healing, can occur with lenvatinib treatment. Managing these adverse events is also important for the use of lenvatinib. In this mini-review article, we outline the current state, toxicity, and future prospects of lenvatinib toward thyroid cancer, hepatocellular carcinoma, renal cell carcinoma, and lung cancer.

Comparison of quality of life between 2-year and 3-or-more-year administration of leuprorelin acetate every-3-months depot in combination with tamoxifen as adjuvant endocrine treatment in premenopausal patients with endocrine-responsive breast cancer: a randomized controlled trial.

BACKGROUND: We conducted an open-label, randomized controlled trial evaluating the appropriate treatment duration of leuprorelin acetate 3-month depot, TAP-144-SR (3M), administered postsurgically every 3 months for 2 years versus 3 or more (up to 5) years, in combination with tamoxifen, for 5 years in premenopausal endocrine-responsive breast cancer patients and reported similar survival benefit in the two treatment groups. We hereby present patient-reported quality of life (QOL) data obtained from this trial. METHODS: Three self-administered QOL questionnaires (QOL-ACD, QOL-ACD-B, FACT-ES subscale) were used, and the difference in QOL score changes between the two groups was analyzed using a mixed-effects model for repeated measures. RESULTS: Eligible patients (N = 222) were randomly assigned to a 2-year (2YG, N = 112) or 3-or-more-year treatment group (3YG, N = 110). The time courses of the three QOL scores during the trial period were similar in the two groups. The mean changes in the QOL scores from week 96 were largely stable through week 240 in the 3YG, but showed significantly greater improvement in the score changes from week 96 in the 2YG than the 3YG. Symptoms associated with menopause such as hot flashes and sweating contributed to these results. Menstruation recovery was associated with significantly greater improvement of these symptoms in the 2YG than the 3YG. CONCLUSIONS: Patient-reported menopause-associated symptoms and QOL improved after discontinuation of the LH-RH agonist administration and menstruation recovery. QOL information should be a consideration in long-term treatment.

Analysis of gender-based differences among surgeons in Japan: results of a survey conducted by the Japan Surgical Society. Part. 2: personal life.

PURPOSE: To assess the true conditions and perceptions of the personal lives of men and women working as surgeons in Japan. METHODS: In 2014, all e-mail subscribed members of the Japan Surgical Society (JSS, n = 29,861) were invited to complete a web-based survey. The questions covered demographic information, work environment, and personal life (including marital status, childcare, and nursing care for adult family members). RESULTS: In total, 6211 surgeons (5586 men and 625 women) returned the questionnaires, representing a response rate of 20.8%. Based on the questionnaire responses, surgeons generally prioritize work and spend most of their time at work, although women with children prioritize their family over work; men spend significantly fewer hours on domestic work/childcare than do their female counterparts (men 0.76 h/day vs. women 2.93 h/day, p < 0.01); and both men and women surgeons, regardless of their age or whether they have children, place more importance on the role of women in the family. CONCLUSIONS: The personal lives of Japanese surgeons differed significantly according to gender and whether they have children. The conservative idea that women should bear primary responsibility for the family still pertains for both men and women working as surgeons in Japan.

Analysis of gender-based differences among surgeons in Japan: results of a survey conducted by the Japan Surgical Society. Part 1: Working style.

PURPOSE: To assess the working styles of men and women working as surgeons in Japan. METHODS: In July, 2014, the Japan Surgical Society invited all their members (n = 29,861), through an internet campaign, to participate in a nationwide survey of surgeons. The items investigated in this descriptive study included demographic information and working styles, based on a questionnaire. RESULTS: In total, 6211 surgeons participated (response rate 20.8%, 5586 men and 625 women). The largest age stratum was 40-49 years for men and 30-39 years for women. Overall, respondents identified their labor contract, including salary and work hours, as the highest priority for improvement. Women with children were more likely to be part-time employees, work fewer hours, and take fewer house calls/on-calls than their male counterparts. Moreover, women of all ages earned a lower annual income than men, irrespective of whether they had children. Perception scores for discrimination related to work and promotion were significantly higher among women than men (p < 0.01 and p = 0.011, respectively). CONCLUSIONS: A significant difference in working style was observed between men and women working as surgeons in Japan.

High density of CD204-positive macrophages predicts worse clinical prognosis in patients with breast cancer.

Recent studies have indicated the clinical significance of tumor-associated macrophages (TAM) in several malignant tumors including breast cancer. Although recent studies have focused on CD68-positive or CD163-positive TAM in breast cancer, no study has investigated the significance of CD204-positive TAM in breast cancer. We found that CD204 expression on macrophages was evaluated following stimulation with the conditioned medium (CM) of breast cancer cell lines. Paraffin sections of 149 breast cancer samples which were diagnosed as invasive ductal carcinoma were immunohistochemically analyzed for CD68, CD163 and CD204 expression. The results of analyses indicated that a high number of CD204-positive TAM was associated with worse clinical prognoses, including relapse-free survival, distant relapse-free survival and breast cancer-specific survival; however, neither the numbers of CD68-positive or CD163-positive TAM were associated with clinical courses. Of the clinicopathological factors investigated, estrogen receptor, Ki-67 index, hormone subtype, and histological grade were significantly related to the increased number of CD163-positive and CD204-positive TAM. These data indicate the clinical significance of CD204-positive TAM in breast cancer progression and CD204 is a marker for predicting clinical prognosis in breast cancer.

Safety and effectiveness of eribulin in Japanese patients with locally advanced or metastatic breast cancer: a post-marketing observational study.

Background This large-scale study was conducted to evaluate the safety and effectiveness of eribulin for the treatment of inoperable or recurrent breast cancer in real-world settings in Japan. Methods Between July and December 2011, eligible patients with inoperable or recurrent breast cancer receiving eribulin for the first time were centrally registered and observed for 1 year. Eribulin was administered intravenously (1.4 mg/m2) on days 1 and 8 of every 3-week cycle. The primary endpoint was the frequency and intensity of adverse drug reactions (ADRs). Secondary endpoints included overall response rate (ORR) and time to treatment failure (TTF). Results Of 968 patients registered at 325 institutions, 951 and 671 were included in the safety and effectiveness analyses, respectively. In the safety population, ADRs were observed in 841 patients (88.4%). The most common (≥15% incidence) were neutropenia (66.6%), leukopenia (62.4%), lymphopenia (18.4%), and peripheral neuropathy (16.8%). The most common grade ≥ 3 ADRs (>5% incidence) were neutropenia (59.8%), leukopenia (50.5%), lymphopenia (16.1%), and febrile neutropenia (7.7%). In the effectiveness population, ORR was 16.5% (95% confidence interval: 13.7, 19.4). The median TTF was 127 days (95% confidence interval: 120, 134). Conclusions The safety and effectiveness profile of eribulin was consistent with prior studies. Eribulin had a favorable risk-benefit balance when used in real-world clinical settings.

Prevalence of ESR1 E380Q mutation in tumor tissue and plasma from Japanese breast cancer patients.

BACKGROUND: ESR1 mutations have attracted attention as a potentially important marker and treatment target in endocrine therapy-resistant breast cancer patients. The E380Q mutation, which is one of the ESR1 mutations, is associated with estradiol (E2) hypersensitivity, increased DNA binding to the estrogen response element, and E2-independent constitutive trans-activation activity, but its frequency in ESR1 mutations remains unknown. The present study aimed to investigate the E380Q mutation in comparison with the other representative ESR1 mutations. METHODS: We screened a total of 62 patients (66 tumor tissues and 69 plasma cell-free DNA (cfDNA)) to detect ESR1 mutations (E380Q, Y537S, Y537N, Y537C, and D538G) using droplet-digital polymerase chain reaction. Plasma was collected at more than two points of the clinical course, in whom changes of ESR1 mutations under treatment were investigated. RESULTS: We detected ESR1 mutations in 21% (12/57) of MBCs. The E380Q ESR1 mutation was found in 16% (2/12) and the other ESR1 LBD mutations were five (41.6%) of Y537S, and four each (33.3%) of D538G, Y537N, and Y537C, in 12 ESR1 mutant breast cancer patients. Five tumors had multiple ESR1 mutations: three had double ESR1 mutations; Y537S/E380Q, Y37S/Y537C, and Y537S/D538G, and two had triple ESR1 mutations; Y537S/Y537N/D538G. In plasma cfDNA analysis, the E380Q mutation was not detected, but increases in other ESR1 mutations were detected in 46.2% (6/13) of MBC patients under treatment. CONCLUSIONS: We have shown that there are distinct populations of ESR1 mutations in metastatic tissue and plasma. Each ESR1 mutation may have different clinical significance, and it will be necessary to investigate them all.

Differential expression of estrogen receptor α, ß1, and ß2 in lobular and ductal breast cancer.

The role of estrogen receptor (ER) α as a target in treatment of breast cancer is clear, but those of ERß1 and ERß2 in the breast remain unclear. We have examined expression of all three receptors in surgically excised breast samples from two archives: (i): 187 invasive ductal breast cancer from a Japanese study; and (ii) 20 lobular and 24 ductal cancers from the Imperial College. Samples contained normal areas, areas of hyperplasia, and in situ and invasive cancer. In the normal areas, ERα was expressed in not more than 10% of epithelium, whereas approximately 80% of epithelial cells expressed ERß. We found that whereas ductal cancer is a highly proliferative, ERα-positive, ERß-negative disease, lobular cancer expresses both ERα and ERß but with very few Ki67-positive cells. ERß2 was expressed in 32% of the ductal cancers, of which 83% were postmenopausal. In all ERß2-positive cancers the interductal space was filled with dense collagen, and cell nuclei expressed hypoxia-inducible factor 1α. ERß2 expression was not confined to malignant cells but was strong in stromal, immune, and endothelial cells. In most of the high-grade invasive ductal cancers neither ERα nor ERß was expressed, but in the high-grade lobular cancer ERß was lost and ERα and Ki67 expression were abundant. The data show a clear difference in ER expression between lobular and ductal breast cancer and suggest (i) that tamoxifen may be more effective in late than in early lobular cancer and (ii) a potential role for ERß agonists in preventing in situ ductal cancers from becoming invasive.

Fibroblast growth factor receptor-1 protein expression is associated with prognosis in estrogen receptor-positive/human epidermal growth factor receptor-2-negative primary breast cancer.

Recently, research into the development of new targeted therapies has focused on specific genetic alterations to create advanced, more personalized treatment. One of the target genes, fibroblast growth factor receptor-1 (FGFR1), has been reported to be amplified in estrogen receptor (ER)-positive subtype breast cancer, and is considered one possible mechanism of endocrine resistance through cross-talk between ER and growth factor receptor signaling. We performed a comprehensive analysis of FGFR1 at the levels of gene copy number, transcript and protein expression, and examined the relationships between FGFR1 status and clinicopathological parameters, including prognosis in 307 ER-positive/HER2-negative primary breast cancer patients treated with standard care at our institute. Most notably, a high level of FGFR1 protein expression was observed in 85 patients (27.7%), and was positively associated with invasive tumor size (P = 0.039). Furthermore, univariate analysis revealed that high FGFR1 protein expression was significantly correlated with poor relapse-free survival rate (P = 0.0019, HR: 2.63, 95% confidence interval: 1.17-5.98), and showed a tendency towards an increase in recurrent events if the observation period extended beyond the 5 years of the standard endocrine treatment term. FGFR1 gain/amplification was found in 43 (14.0%) patients, which was only associated with higher nuclear grade (P = 0.010). No correlation was found between FGFR1 mRNA expression levels and any clinicopathological factors. Overall, the level of FGFR1 protein expression may be a biomarker of ER-positive/HER2-negative primary breast cancer with possible resistance to standard treatment, and may be a useful tool to identify more specific patients who would benefit from FGFR-1 targeted therapy.

GANP protein encoded on human chromosome 21/mouse chromosome 10 is associated with resistance to mammary tumor development.

Human chromosome 21 is known to be associated with the high risk of hematological malignancy but with resistance to breast cancer in the study of Down syndrome. In human cancers, we previously observed the significant alterations of the protein expression encoded by the ganp/MCM3AP gene on human chromosome 21q22.3. Here, we investigated GANP protein alterations in human breast cancer samples (416 cases) at various stages by immunohistochemical analysis. This cohort study clearly showed that expression of GANP is significantly decreased in human breast cancer cases with poor prognosis as an independent risk factor (relapse-free survival, hazard ratio = 2.37, 95% confidence interval, 1.27-4.42, P = 0.007 [univariate analysis]; hazard ratio = 2.70, 95% confidence interval, 1.42-5.13, P = 0.002 [multivariate analysis]). To investigate whether the altered GANP expression is associated with mammary tumorigenesis, we created mutant mice that were conditionally deficient in the ganp/MCM3AP gene using wap-cre recombinase transgenic mice. Mammary gland tumors occurred at a very high incidence in female mammary gland-specific GANP-deficient mice after severe impairment of mammary gland development during pregnancy. Moreover, tumor development also occurred in female post parous GANP-heterodeficient mice. GANP has a significant role in the suppression of DNA damage caused by estrogen in human breast cancer cell lines. These results indicated that the GANP protein is associated with breast cancer resistance.

Prediction of sentinel lymph node status using single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging of breast cancer.

PURPOSE: Single-photon emission computed tomography (SPECT)/computed tomography (CT) improves the anatomical identification of sentinel lymph nodes (SNs). We aimed to evaluate the possibility of predicting the SN status using SPECT/CT. METHODS: SN mapping using a SPECT/CT system was performed in 381 cases of clinically node-negative, operable invasive breast cancer. We evaluated and compared the values of SN mapping on SPECT/CT, the findings of other modalities and clinicopathological factors in predicting the SN status. RESULTS: Patients with SNs located in the Level I area were evaluated. Of the 355 lesions (94.8 %) assessed, six cases (1.6 %) were not detected using any imaging method. According to the final histological diagnosis, 298 lesions (78.2 %) were node negative and 83 lesions (21.7 %) were node positive. The univariate analysis showed that SN status was significantly correlated with the number of SNs detected on SPECT/CT in the Level I area (P = 0.0048), total number of SNs detected on SPECT/CT (P = 0.011), findings of planar lymphoscintigraphy (P = 0.011) and findings of a handheld gamma probe during surgery (P = 0.012). According to the multivariate analysis, the detection of multiple SNs on SPECT/CT imaging helped to predict SN metastasis. CONCLUSIONS: The number of SNs located in the Level I area detected using the SPECT/CT system may be a predictive factor for SN metastasis.

Clinical significance of estrogen receptor ß in breast and prostate cancer from biological aspects.

Breast and prostate cancers are among the most common of all cancers. They are referred to as hormone-dependent cancers, because estrogen and androgen are involved in their development and growth. The effects of these hormones are mediated by their respective receptors, estrogen receptor (ER) α and androgen receptor. Around 18 years ago, a second ER, ERß, which has a very similar structure to ERα, was discovered. Its function has been investigated using a variety of methods and biological systems, leading to our present understanding that ERß can interact with or inhibit ERα and androgen receptor function directly and/or indirectly, suppress cell growth, and influence responsiveness to endocrine therapy. In order to apply the "inhibition of cell growth" function to cancer treatment, several specific ERß agonists have been synthesized and are being tested for effectiveness in cancer treatment. We need to keep our eyes on ERß.

Prognostic role of PIK3CA mutations of cell-free DNA in early-stage triple negative breast cancer.

PIK3CA is an oncogene that encodes the p110α component of phosphatidylinositol 3-kinase (PI3K); it is the second most frequently mutated gene following the TP53 gene. In the clinical setting, PIK3CA mutations may have favorable prognostic value for hormone receptor-positive breast cancer patients and, during the past few years, PIK3CA mutations of cell-free DNA (cfDNA) have attracted attention as a potential noninvasive biomarker of cancer. However, there are few reports on the clinical implications of PIK3CA mutations for TNBC patients. We investigated the PIK3CA major mutation status of cfDNA as a noninvasive biomarker of cancer using droplet digital polymerase chain reaction (ddPCR), which has high level sensitivity and specificity for cancer mutation, in early-stage 49 triple negative breast cancer (TNBC) patients. A total of 12 (24.4%) of 49 patients had PIK3CA mutations of cfDNA. In a median follow up of 54.4 months, the presence of PIK3CA mutations of cfDNA had significant impacts on relapse-free survival (RFS; P = 0.0072) and breast cancer-specific survival (BCSS; P = 0.016), according to the log-lank test. In a Cox proportional hazards model, the presence of PIK3CA mutations of cfDNA had significant prognostic value in the univariate and multivariate analysis. Additionally, the presence of PIK3CA mutations of cfDNA was significantly correlated with positive androgen receptor phosphorylated form depending on PI3K signaling pathway (pAR) which is independent favorable prognostic factors of TNBC. We demonstrated that the presence of PIK3CA major mutations of cfDNA could be a discriminatory predictor of RFS and BCSS in early-stage TNBC patients and it was associated with PI3K pathway-dependent AR phosphorylation.

Clinical benefit of sequential use of endocrine therapies for metastatic breast cancer.

Sequential use of endocrine agents is common in estrogen receptor (ER)-positive metastatic breast cancer (MBC). In premenopausal women with MBC, tamoxifen and/or a luteinizing hormone-releasing hormone (LH-RH) agonist are options for endocrine treatment. Meta-analysis showed that the combination of the two agents is superior to either monotherapy. Under ovarian ablation or function-suppression, an agent used to treat postmenopausal women, such as the aromatase inhibitor (AI), fulvestrant, becomes possible as a subsequent therapy. In postmenopausal women, endocrine treatment options are widely available and an optimal sequence has not yet to be determined. Options for first-line therapy of metastatic disease include an AI for women who have received adjuvant tamoxifen, or tamoxifen for patients who have received adjuvant AI. In addition, data suggest that fulvestrant is a promising therapeutic option that has proven efficacy in the treatment of postmenopausal women with MBC. Other agents that may be used in the sequence include a steroidal AI or a progestin. Furthermore, estrogen additive therapy by with diethylstilbestrol or ethinylestradiol has recently been revived and showed a high response rate as a salvage endocrine therapy, although its mechanism of action is still unclear. Thus, sequential use of endocrine therapies, especially the use of a subsequent therapy with a different mechanism of action to the prior therapy, has a beneficial effect in maintaining a good quality of life and extending survival for MBC with hormone responsiveness.