Japanese Breast Cancer Patients Research Articles

Abstract PO3-15-08: Validation for prognostic staging based AJCC 8th edition with nuclear grade in Japanese breast cancer patients: A multicenter retrospective study

Abstract Introduction. The American Joint Committee on Cancer (AJCC) 8th edition of breast cancer classification introduced the concept of "prognostic stage," which is based on anatomic classification (TNM classification) plus four biomarkers: estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER2), and histological grading (HG). In Japan, however, the introduction of histological classification has been passive and slow, and the nuclear grading (NG) has been used so far. Objective. Our aim is to compare the prognostic staging classification in the AJCC, 8th edition which substitutes NG for HG (AJCC8th-NG) with the TNM classification, and to confirm the usefulness of AJCC8th-NG classification. Methods. We collected 5229 patients with primary breast cancer operated on between 2005 and 2013 at six institutions affiliated with Kyushu University Hospital in Japan, for whom prognosis was available. We retrospectively evaluated the 7-year survival rates based on the TNM classification and the AJCC8th-NG classification, based on the pathological diagnosis of their surgeries. Results. Median age was 58 years (24-99), 5210 (99.6%) were female, and the 7-year survival rate of all eligible patients was 93.2%. The changes in the number of cases by stage were observed as follows: Stage 0 (16.5%), Stage IA (42.3% to 56.2%), Stage IB (0.3% to 8.8%), Stage IIA (21.5% to 6.9%), Stage IIB (9.7% to 3.1%), Stage IIIA (3.9% to 3.5%), Stage IIIB (1.5% to 1.9%), Stage IIIC (2.1% to 0.9%), Stage IV (1.9%). The changes in 7-year survival rates were observed as follows: Stage 0 (96.1%), Stage IA (96.8% → 96.5%), Stage IB (93.7% → 93.4%), Stage IIA (93.1% → 87.8%), Stage IIB (88.5% → 84.6%), Stage IIIA (86.9% → 80.4%), Stage IIIB (78 .7% to 84.4%), Stage IIIC (79.8% to 58.4%), and Stage IV (51.9%). (TNM classification →AJCC8th-NG classification) Both TNM classification and AJCC8th-NG classification were significantly associated with prognosis. AJCC8th-NG classification was more stratified. In AJCC 8th-NG Stage IB, which is the largest population in all patients, 42% of that were triple-negative type (TN) downstaging from TNM Stage IA and 58% were luminal type downstaging from TNM Stage II-IIIA. In AJCC 8th-NG Stage IIIC, which was changed the most with biomarkers, 52% of that were TN upstaging from TNM Stage IIIA-IIIB. On the other hand, 50% of AJCC 8th-NG Stage IIIB with a favorable prognosis were ER-positive or HER2-positive downstaged from TNM Stage IIIC. Discussion TN breast cancer generally has a poor prognosis. However, HER2-positive breast cancer, which used to have a poor prognosis, is said to have a favorable prognosis after the availability of anti-HER2 drugs. This time, we examined cases after 2005 when anti-HER2 drugs became available in Japan, but the results did not show that HER2-positive breast cancer had a better prognosis than HER2-negative breast cancer. In this study, we were unable to confirm the use of anti-HER2 drugs. In the AJCC 8th classification, it seems necessary to consider whether or not treatment is being provided. If all patients are treated, the prognostic stratification will become clearer. Conclusion. Our study could show that AJCC8th-NG classification was useful for predicting prognosis same as AJCC8th classification in the relatively large cohort. Citation Format: Kazuhisa Kaneshiro, Mai Yamada, Saori Hayashi, Kenichiro Koga, Michiyo Saimura, Naoki Otomo, Shuyo Umeda, Keisei Anan, Masayuki Okido, Takafumi Morisaki, Masafumi Nakamura, Makoto Kubo. Validation for prognostic staging based AJCC 8th edition with nuclear grade in Japanese breast cancer patients: A multicenter retrospective study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-15-08.

36P Fertility preservation & hboc genetic testing in young japanese breast cancer patients: The role of insurance coverage

36P Fertility preservation & hboc genetic testing in young japanese breast cancer patients: The role of insurance coverage

Actionability of comprehensive genomic profiling compared to the tissue-based and plasma-based assay in patients with metastatic breast cancer: A real-world study.

1101 Background: Comprehensive genomic profiling (CGP) was officially approved in August 2021 in Japan under the national health insurance system with three CGP tests in June 2019: FoundationOne CDx (F1CDx), OncoGuide NCC Oncopanel (NCC), which are tissue-based assay (TBA), and FoundationOne Liquid CDx (F1LCDx, starting in August 2021) which is plasma-based panel (PBA). The Center for Cancer Genomics and Advanced Therapeutics (C-CAT) has collected genomic and clinical data of 2,617 Japanese breast cancer patients as of October 2022. Here we assess these PBA and TBA to detect pathogenic or driver alterations informative for matched therapy in patients with metastatic breast cancer (mBC). Methods: We queried consecutive mBC patient clinical-genomic data through the C-CAT Research-Use Portal from June 2019 to October 2022 were categorized based on PBA or TBA. We used ClinVar to identify if the called somatic alterations were pathogenic or likely pathogenic, and BoostDM (https://www.intogen.org/boostdm/search) to identify potential driver mutations of breast cancer. The proposed rate of matched therapy was determined. The incidence rates were compared using the Pearson χ2 test. Results: Of 2,617 pts who underwent the CGP test, 2,259 (86%) received TBA (74% F1CDx and 12% NCC). The proportion of pts with ≥1 pathogenic variant with PBA and TBA was not significant (71.5%vs.72.7%; p=0.88), but the proportion of pts with ≥1 driver mutation was significantly higher with PBA than TBA (75.4% vs. 69.8%; p = 0.03). Regarding the proportion of pts who matched therapy or clinical trials presented among the pts for whom data were available, PBA was significantly lower than TBA (27.7% vs.38.5%, p < 0.001). Although data on post-treatment is still being collected, the proportion of tested patients that received matched therapies recommended by molecular tumor boards of each institute was significantly lower for PBA (4.2%vs. 8.3%; p = 0.007). Conclusions: This study is the first analysis of CGP for mBC in Japan using the C-CAT utilization program. Although significant alterations were well-detected in PBA, the proportion of pts who received matched-therapy post-testing was low for PBA. Possible causes include that PBA has fewer companion diagnoses than TBA in Japan and that PBA is more often used in later lines.

P292 Cell-free DNA (cfDNA) profiling using Guardant360 in Japanese metastatic breast cancer patients

P292 Cell-free DNA (cfDNA) profiling using Guardant360 in Japanese metastatic breast cancer patients

Characteristics of female breast cancer in japan: annual report of the National Clinical Database in 2018

Information regarding patients who were treated for breast cancer in 2018 was extracted from the National Clinical Database (NCD), which is run by Japanese physicians. This database continues from 1975, created by the Japanese Breast Cancer Society (JBCS). A total of 95,620 breast cancer cases were registered. The demographics, clinical characteristics, pathology, surgical treatment, adjuvant chemotherapy, adjuvant endocrine therapy, and radiation therapy of Japanese breast cancer patients were summarized. We made comparisons with other reports to reveal the characteristics of our database. We also described some features in Japanese breast cancer that changed over time. The unique characteristics of breast cancer patients in Japan may provide guidance for future research and improvement in healthcare services.

Correction to: Clinical outcome of embryo cryopreservation in Japanese breast cancer patients: pregnancy rates after transfer of thawed embryos

Correction to: Clinical outcome of embryo cryopreservation in Japanese breast cancer patients: pregnancy rates after transfer of thawed embryos

Clinical outcome of embryo cryopreservation in Japanese breast cancer patients: pregnancy rates after transfer of thawed embryos.

To examine pregnancy outcomes after cryopreserved embryo transfer (ET) in breast cancer patients and to investigate the effect of controlled ovarian hyperstimulation (COH) as well as that of aromatase inhibitor (AI) administration and of the random start (RS) ovarian stimulation method. This retrospective study covered 126 patients who underwent embryo cryopreservation between 2010 and 2019. Thirty-one patients underwent frozen embryo transfer (FET), and we examined resulting pregnancy rates (PRs) and live birth rates (LBRs) in those who did and did not undergo COH and in relation to the AI and RS methods. PR and LBR per patient were higher among patients who underwent COH than among those who did not. PR per ET did not differ from that documented for non-cancer infertility patients, after adjustment for age. The PR and LBR did not differ between use and non-use of AI (27.8% vs 35.2%). In addition, there was no significant difference in the PR or LBR between RS and conventional start ovarian stimulation (33.3% vs 30.8%). No prenatal fetal abnormalities were observed in 8 cases (including 5 AI cases and 2 RS cases). This study showed that the outcome of FET after FP was equivalent to that seen in non-cancer patients. Further, neither use of AI nor the RS method influenced LBR. COH including use of AI and the RS method are useful in FP for collecting and freezing many embryos within a short period and for increasing the per patient LBR after cancer treatment.

Abstract P1-15-02: Low incidence of hepatitis B reactivation after chemotherapy in Japanese breast cancer patients with resolved HBV

Abstract Background: Recently, chemotherapy-induced reactivation of hepatitis B virus (HBV) has been reported not only in patients with HBV surface antigen positive (HBsAg+) but also in patients with resolved HBV (HBsAg-, anti-HBV-core antibody positive (anti-HBc+). The incidnce of HBV reactivation after adjuvant/neo-adjuvant chemotherapy for breast cancer in patients with resolved HBV infection remains unclear. In this study, we surveyed the incidence of HBV reactivation in Japanese breast cancer patients who received adjuvant/neo-adjuvant chemotherapy. Methods: A total of 3042 breast cancer patients who received neoadjuvant and/or adjuvant chemotherapy from June 2008 to December 2016 were included in this study. HBsAg, anti-HBc and anti-HBV-surface antibody (anti-HBs) were tested before chemotherapy. Serum HBV-DNA levels were subsequently measured and monitored for one year after the completion of adjuvant/neo-adjuvant chemotherapy if the patient exhibited a resolved HBV infection. Results: Of the 3042 patients (pts), 32 (1.05%)cases were positive for HBsAg and 2992 pts were negative for HBsAg. 301 pts (9.9 %) were revealed resolved HBV infection; 221 pts were with anti-HBc+ and anti-HBs+, 40 pts were with anti-HBc+ and anti-HBs-, and 130 pts were with anti-HBc- and anti-HBs+. Of the 130 pts with anti-HBc- and anti-HBs+, 77 pts were previously vaccinated for hepatitis B. The antibody-positive rate by age group was 2.7% (1/37) for patients in their 20s, 4.1% (14/344) for those in their 30s, 6.5% (67/1037) for those in their 40s, 9.4% (77/817) for those in their 50s, 16.6% (109/655) for those in their 60s, 20% (30/150) for those in their 70s, and 0% (0/2) for those in their 80s. Among the 301 pts with resolved HBV infection, 71 pts were monitored for one year after the completion of their chemotherapy. The median monitoring period was 579 days (386-3458). In our monitoring period, only one patient (1.4%) was diagnosed with HBV reactivation based on a slightly elevated HBV-DNA level at 1-year-test. No death or hepatitis due to HBV reactivation occurred during the monitoring period. Conclusions: The prevalence of resolved HBV infection in Japan showed an increasing trend with age. Adjuvant/neoadjuvant chemotherapy for breast cancer patients with resolved HBV infection has a risk of HBV reactivation. Our study suggested the risk of reactivation was low and the risk of a flare of HBV disease could be controlled with screening and carefully monitoring. Citation Format: Takayo Fukuda, Masaya Hattori, Yukinori Ozaki, Lina Inagaki, Mari Hosonaga, Ippei Fukada, Kokoro Kobayashi, Fumikata Hara, Takayuki Kobayashi, Sachiyo Yoshio, Takayuki Ueno, Toshimi Takano, Shinji Ohno. Low incidence of hepatitis B reactivation after chemotherapy in Japanese breast cancer patients with resolved HBV [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-15-02.

Abstract P3-16-04: Estimation of willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A): The main study findings

Abstract Background In 2019, the Japanese government has introduced the economic valuation to healthcare system. However, the threshold for determining cost-effectiveness-analysis has yet to be adequately studied. Therefore, we have designed a study to examine the financial value of “life” and “health” based on willingness-to-pay (WTP) considered by patients with primary and metastatic breast cancer (PBC and MBC) in Japan. Methods This study is conducted by forty-five hospitals under the Breast Cancer Study Group of Japan Clinical Oncology Group (JCOG). In the preliminary study, 168 patients (84 patients with PBC and 84 patients with MBC) from 20 to 79 years of age paying medical costs were examined their WTP for setting up the dichotomous-choice method survey form for using in the main study. Virtual scenario-specific treatments to avoid the recurrence and death of breast cancer for one year for PBC patients, and to prolong the survival period for one year for the patients with MBC were presented. The patients were evaluated how much money would pay to receive the treatment in a self-written answer and the amount of WTP that would be presented in the main study was determined. In the main study, 1,620 patients (810 patients with PBC and 810 patients with MBC) were surveyed to their WTP for hypothetical scenarios using the dichotomous-choice method survey form. With the two-step dichotomous-choice method, if the first stage response was yes, a higher amount was displayed for the second stage. If the first stage response was no, a lower amount was shown for the second stage. For the main analysis, the acceptance probability curve was calculated using the parametric method. The calculation was based on the obtained responses and median WTP, which was determined by calculating the amount at which the acceptance probability curve is at 50%. The obtained amount was converted to WTP per one QALY based on the displayed question content. Results Completed surveys were collected from 716 PBC patients (88.4%) and 702 patients (86.7%). Based on the preliminary study, the amount of WTP offering in the first stage was set 5 million yen (JPY) (50,000 USD), and offering in the second stage was 7 million JPY (70,000 USD) for those who responded accepting the scenario treatment and 3 million JPY (30,000 USD) for those who responded refusing. We obtained point estimates of WTP for each virtual scenario treatments. The WTP of the two hypothetical scenarios for PBC patients were as follows; scenario 1) the treatment to gain one year without recurrence: 2.06 million JPY (20,600 USD), scenario 2) the treatment that reduces risk of recurrence by 40%: 2.40 million JPY (24,000 USD). The WTP of the two hypothetical scenarios for MBC patients were as follows; scenario 3) the treatment that can prolong survival for one year in current health condition: 2.81 million JPY (28,100 USD), scenario 4) the treatment that can prolong survival by one year in the health condition before having breast cancer: 2.92 million JPY (29,200 USD). Conclusion We created hypothetical 1-quality-adjusted survival year (QALY) scenarios for breast cancer patients with different disease status and validated them using the contingent valuation method. Our results demonstrate that WTP per 1QALY varies with the disease status of breast cancer. Therefore, we conclude that we cannot simply use a uniform threshold when examining the cost-effectiveness of medical interventions in breast cancer as a unit of cost/QALY. Citation Format: Tsuguo Iwatani, Fumikata Hara, Tadahiko Shien, Masato Takahashi, Norikazu Masuda, Yasuaki Sagara, Keita Sasaki, Junki Mizusawa, Haruhiko Fukuda, Takaru Shiroiwa, Hiroji Iwata. Estimation of willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A): The main study findings [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-16-04.

Self-Transcendence of Japanese Female Breast Cancer Patients with Hereditary Breast and Ovarian Cancer Syndrome

Objective:The present study examined self-transcendence of Japanese female breast cancer patients with hereditary breast and ovarian cancer (HBOC) syndrome.Methods:Semi-structured interviews were conducted with 13 women with HBOC in their thirties to sixties, who consented to participate in the study. The obtained data were analyzed using a modified grounded theory approach.Results:The analysis yielded seven categories of self-transcendence in women with HBOC: (1) the ability to face oneself while seeking optimal strategies to continue living; (2) the ability to come to terms with blood conditions inherited from previous generations; (3) the ability to use one's own experiences as a patient with HBOC to help others; (4) the ability to share mutual support with others; (5) the ability to accept the diverse views on HBOC; (6) the ability to break free from fixed ideas and live with HBOC; and (7) the ability to live with future perspectives.Conclusions:The self-transcendence of Japanese female breast cancer patients with HBOC can be described as not giving up; confronting one's lineage, which is passed down from generation to generation, even as one is haunted and emotionally affected by the lifelong risk of developing cancer or facing death; and valuing not just oneself but also others through interactions with them. These abilities formed the foundation for the self-transcendence of the women in this study. In addition, because the women with this condition started valuing not just themselves but also others, they developed the ability to accept the diverse views surrounding HBOC and to coexist with their condition while being forward-looking.

Impact of serum vitamin D on the response and prognosis in breast cancer patients treated with neoadjuvant chemotherapy

BackgroundSeveral studies have recently reported that the relationships between serum vitamin D and the prognosis or the pathological response to neoadjuvant chemotherapy (NAC) in breast cancer. However, there are no data regarding the clinical impacts of the vitamin D in Japanese breast cancer patients so far.Patients and methodsIn the present study, a total of 250 patients with clinical Stage I–III primary breast cancer who were treated with NAC and subsequently underwent definitive surgery were included. Serum 25-hydroxvitamin D (25(OH)D) levels were evaluated using blood samples obtained before NAC.ResultsThe serum 25(OH)D was positively associated with age, and the serum 25(OH)D was significantly higher in postmenopausal women than that in pre/peri-menopausal women. Serum 25(OH)D level was not associated with the achievement of pathological complete response (pCR) in this cohort. The low 25(OH)D levels were significantly associated with shorter time to distant recurrence (TTDR). According to the univariate analysis, high clinical stage before NAC (cStage III) and low serum 25(OH)D level were significantly associated with the shorter TTDR, and pCR was significantly associated with the longer TTDR. According to a multivariate analysis, low serum 25(OH)D level were independent poor prognostic factors for TTDR.ConclusionsThe low 25(OH)D levels were significantly associated with poorer prognosis in Japanese women with operable breast cancer patients treated with NAC.

Optimization of prediction methods for risk assessment of pathogenic germline variants in the Japanese population.

Predicting pathogenic germline variants (PGVs) in breast cancer patients is important for selecting optimal therapeutics and implementing risk reduction strategies. However, PGV risk factors and the performance of prediction methods in the Japanese population remain unclear. We investigated clinicopathological risk factors using the Tyrer‐Cuzick (TC) breast cancer risk evaluation tool to predict BRCA PGVs in unselected Japanese breast cancer patients (n = 1,995). Eleven breast cancer susceptibility genes were analyzed using target‐capture sequencing in a previous study; the PGV prevalence in BRCA1, BRCA2, and PALB2 was 0.75%, 3.1%, and 0.45%, respectively. Significant associations were found between the presence of BRCA PGVs and early disease onset, number of familial cancer cases (up to third‐degree relatives), triple‐negative breast cancer patients under the age of 60, and ovarian cancer history (all P < .0001). In total, 816 patients (40.9%) satisfied the National Comprehensive Cancer Network (NCCN) guidelines for recommending multigene testing. The sensitivity and specificity of the NCCN criteria for discriminating PGV carriers from noncarriers were 71.3% and 60.7%, respectively. The TC model showed good discrimination for predicting BRCA PGVs (area under the curve, 0.75; 95% confidence interval, 0.69‐0.81). Furthermore, use of the TC model with an optimized cutoff of TC score ≥0.16% in addition to the NCCN guidelines improved the predictive efficiency for high‐risk groups (sensitivity, 77.2%; specificity, 54.8%; about 11 genes). Given the influence of ethnic differences on prediction, we consider that further studies are warranted to elucidate the role of environmental and genetic factors for realizing precise prediction.

Development of Japanese Versions of the Control Preferences Scale and Information Needs Questionnaire: Role of Decision-Making and Information Needs for Japanese Breast Cancer Patients.

PurposeThe importance of shared decision-making (SDM) between physicians and patients is increasingly recognized. In Japan, patients have shown more willingness to participate in treatment if medical professionals provide sufficient information; however, relationships between physicians and patients have traditionally been asymmetric, with patients accepting information from physicians without discussion. To explore the benefits of SDM in cancer treatment, including confidence in treatment decisions, satisfaction with treatment, and trust in healthcare providers, this study developed Japanese versions of the Control Preference Scale (CPS) and Information Needs Questionnaire (INQ).Patients and MethodsReliability and validity of the CPS and INQ were tested with 49 breast cancer patients.ResultsThe CPS showed good test–retest reliability (kappa coefficient: 0.61, weighted kappa coefficient: 0.61, Kendall’s tau coefficient: 0.61) and acceptable criterion validity. The INQ showed adequate consistency; the mean number of circular triads and coefficient of consistency were 3 (range 0–19) and 0.9 (range 0.37–1), respectively. Using the CPS and INQ to identify patients’ roles in decision-making and information needs, results further suggested that breast cancer patients in Japan want to participate in SDM. Medical issues, including disease spread and cure, were found to be of high interest, while social and psychological issues, including sexual attractiveness, genetic risk, and family impact, tended to be low.ConclusionThe Japanese CPS and INQ can be used to assess patients’ needs to improve care. Further, as patients’ information needs change along the care trajectory, these tools should be used throughout treatment.

Prospective study of hair recovery after (neo)adjuvant chemotherapy with scalp cooling in Japanese breast cancer patients

PurposeScalp cooling during chemotherapy infusion to mitigate alopecia for breast cancer patients is becoming widespread; however, studies regarding hair recovery after chemotherapy with scalp cooling are limited. We conducted a prospective study of hair recovery after chemotherapy with scalp cooling.Patients and methodsOne hundred and seventeen Japanese female breast cancer patients who completed planned (neo)adjuvant chemotherapy using the Paxman Scalp Cooling System for alopecia prevention were evaluated for alopecia prevention in our prospective study. We evaluated their hair recovery 1, 4, 7, 10, and 13 months after chemotherapy. Primary outcomes were grades of alopecia judged by two investigators (objective grades) and patients’ answers to the questionnaire regarding the use of a wig or hat (subjective grades).ResultsOf 117 patients, 75 completed scalp cooling during the planned chemotherapy cycles (Group A), but 42 discontinued it mostly after the first cycle (Group B). Objective and subjective grades were significantly better in Group A than in Group B throughout 1 year, and at 4 and 7 months after chemotherapy. When we restricted patients to those with objective Grade 3 (hair loss of > 50%) at 1 month, Group A exhibited slightly faster hair recovery based on the objective grades than Group B. There was less persistent alopecia in Group A than in Group B.ConclusionsScalp cooling during chemotherapy infusion for Japanese breast cancer patients increased the rate of hair recovery and had preventive effects against persistent alopecia.

Abstract PS9-57: Estimation of willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A); preliminary study findings

Abstract BackgroundIn 2019, the Japanese government has decided to introduce the economic valuation to healthcare system. However, the threshold for determining cost-effectiveness-analysis has yet to be adequately studied. Therefore, we have designed a study to examine the financial value of “life” and “health” based on willingness-to-pay (WTP) considered by approximately 1,800 patients with primary and metastatic breast cancer (PBC and MBC) in Japan. Preliminary study has been conducted to set the amount of WTP prior to the main study. Methods This study is conducted by six leading hospitals under the Breast Cancer Study Group of Japan Clinical Oncology Group (JCOG). 168 patients (84 patients with PBC and 84 patients with MBC) from 20 to 79 years of age paying medical costs were examined their WTP for setting up the dichotomous-choice method survey form. Virtual scenario-specific treatments to avoid the recurrence and death of breast cancer for one year for PBC patients, and to prolong the survival period for one year for the patients with MBC were presented. The patients were evaluated how much money would pay to receive the treatment in a self-written answer. The amount of WTP that will be presented in the main study was determined by calculating the median price from these responses based on the protocol. In addition, we conducted surveys of quality-of-life by EQ-5D-5L, social background on patients, and of breast cancer medical condition on doctors. Results Completed surveys were collected from 166 doctors (98.8%) and 139 patients (82.7%). The range of the amount of WTP for scenario-specific treatments among the patients with the patients with PBC was from 0 to 5 million Japanese yen (JPY) (50,000 USD), and among the patients with MBC was from 0 to 10 million JPY (100,000 USD). In accordance with the criteria set forth in advance in the protocol, the amount of WTP that will be presented in the main study was set at 5 million JPY in both PBC and MBC patients. Conclusion We have fixed the cost that will be presented in the main study based on the findings of our preliminary study. The main study will commence around September 2020. Citation Format: Tsuguo Iwatani, Fumikata Hara, Tadahiko Shien, Masato Takahashi, Norikazu Masuda, Hiroyuki Yasojima, Yasuaki Sagara, Tomonori Mizutani, Keita Sasaki, Kenichi Nakamura, Haruhiko Fukuda, Takaru Shiroiwa, Hiroji Iwata. Estimation of willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A); preliminary study findings [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS9-57.

Validity of the prognostication tool PREDICT version 2.2 in Japanese breast cancer patients

IntroductionPREDICT is a prognostication tool that calculates the potential benefit of various postsurgical treatments on the overall survival (OS) of patients with nonmetastatic invasive breast cancer. Once patient, tumor, and treatment details have been entered, the tool will show the estimated 5‐, 10‐, and 15‐year OS outcomes, both with and without adjuvant therapies. This study aimed to conduct an external validation of the prognostication tool PREDICT version 2.2 by evaluating its predictive accuracy of the 5‐ and 10‐year OS outcomes among female patients with nonmetastatic invasive breast cancer in Japan.MethodsAll female patients diagnosed from 2001 to 2013 with unilateral, nonmetastatic, invasive breast cancer and had undergone surgical treatment at Kyushu University Hospital, Fukuoka, Japan, were selected. Observed and predicted 5‐ and 10‐year OS rates were analyzed for the validation population and the subgroups. Calibration and discriminatory accuracy were assessed using Chi‐squared goodness‐of‐fit test and area under the receiver operating characteristic curve (AUC).ResultsA total of 636 eligible cases were selected from 1, 213 records. Predicted and observed OS differed by 0.9% (p = 0.322) for 5‐year OS, and 2.4% (p = 0.086) for 10‐year OS. Discriminatory accuracy results for 5‐year (AUC = 0.707) and 10‐year (AUC = 0.707) OS were fairly well.ConclusionPREDICT tool accurately estimated the 5‐ and 10‐year OS in the overall Japanese study population. However, caution should be used for interpretation of the 5‐year OS outcomes in patients that are ≥65 years old, and also for the 10‐year OS outcomes in patients that are ≥65 years old, those with histologic grade 3 and Luminal A tumors, and in those considering ETx or no systemic treatment.

Prospective observational study estimating willingness-to-pay for breast cancer treatments through contingent valuation method in Japanese breast cancer patients (JCOG1709A).

In April 2016, the Japanese government introduced health technology assessment as a response to rising medical expenses due to ‘medical innovation’. This study investigates how Japanese breast cancer patients who received treatment in Japan consider the financial value (willingness-to-pay; WTP) for their life and health by using the contingent valuation method (CVM) prospectively. First, 168 patients (84 primary breast cancer patients and 84 metastatic breast cancer patients) were pre-examined their WTP with dichotomous-choice method survey form. Next, 1,596 patients (798 primary breast cancer patients and 798 metastatic breast cancer patients) will be surveyed to their WTP for hypothetical scenarios in CVM. Based on our results, we will construct an evaluation axis from the patients’ viewpoint for the cost-effectiveness of clinical trials to establish standard treatments for breast cancer. We believe this research can contribute to create a meaningful healthcare system for patients, clinicians, industries, and healthcare policymakers.

Evaluation of 12 Prognostic Biomarkers by 10 Years&apos; Disease-Free Survival and Cancer-Specific Survival Among Japanese Breast Cancer Patients

Evaluation of 12 Prognostic Biomarkers by 10 Years&apos; Disease-Free Survival and Cancer-Specific Survival Among Japanese Breast Cancer Patients

Frequency of high-risk hormone receptor-positive breast cancer patients was much higher in Japanese breast cancer patients with germline BRCA1/2 mutations than in sporadic breast cancer patients.

Frequency of high-risk hormone receptor-positive breast cancer patients was much higher in Japanese breast cancer patients with germline BRCA1/2 mutations than in sporadic breast cancer patients.

Clinicopathological characteristics, practical treatments, prognosis, and clinical issues of older breast cancer patients in Japan.

Minimal data are available to support the clinical management of older breast cancer patients. Consequently, the standard of care remains unclear. Our aim was to clarify the clinicopathological characteristics, practical treatments, and prognosis of older Japanese breast cancer patients and discuss clinical issues. We reviewed 132,240 cases, diagnosed between 2004 and 2011, from the Japanese Breast Cancer Registry. Focusing on older patients, we compared data among three age groups: 75years and over (n = 27,385), 65-74years (n = 43,839), and 55-64years (n = 61,016). Data revealed the proportions of mucinous and apocrine carcinoma were higher in older patients, and they more frequently had clinical stage II and III cancer. Their ER-positive rates were higher, in contrast to the lower HER2-positive, breast-conserving surgery (BCS), post-BCS irradiation, and adjuvant chemotherapy rates. Almost half of the older patients who underwent chemotherapy received CMF or oral 5FU, during hormone therapy, Tamoxifen was administered more frequently. The overall survival rate decreased with age, but the breast cancer-specific survival (BCSS) at 5years remained similar. The rate of other cause of death in the oldest group was about a half, and more than double that in those aged 55-64years. We showed clinical data of older breast cancer patients in Japan. Their disease was more advanced at the time of diagnosis, post-BCS irradiation and primary systemic chemotherapy were omitted more frequently, and overall, BCSS was similar among age categories, although the rate of other causes of death was higher.