Korean Breast Cancer Research Articles

Abstract P6-06-42: Impact of molecular subtype on overall survival according to age in Korean women

Abstract Introduction: Breast cancer is a heterogeneous diseases, which is based on expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Using these factors, molecular subtype can be determined as luminal A, luminal B, HER2+, and TNBC. This is considered as an important prognostic factor. In breast cancer, age is the one of the important prognostic factors and prognosis is varied according to patients’ age. We performed this study to analyze the impact of molecular subtypes on prognosis of breast cancer according to patients’ age. Patients and methods: We performed this study by using Korean Breast Cancer Society Registration Program data. Total 15,286 patients are included into this study, and they underwent surgery during the period Jan. 2001 to Dec. 2006. All patients were divided into two groups according to age (younger: age≤34, older: age≥35) and molecular subtypes were classified into four groups as follows: luminal A (ER+ and/or PR+, HER2-), luminal B (ER+ and/or PR+ HER2+), HER2+ (ER-, PR-, HER2+), and triple-negative (ER-, PR-, HER2-). We determined prognostic impact of molecular subtype on overall survivals (OS). Clinicopathologic results and OS were compared by chi-square test, Kaplan Meier test, and Cox's hazards model. Results: Younger group more frequently had tumors with negative hormone receptor (ER-/PR-), worse prognostic factors and diagnosed with more advanced stage compared to older group. In univariate analysis, molecular subtype was not related with OS in younger group (p = 0.069), but not in older group (p<0.001). In multivariate analysis, molecular subtype was an independent prognostic factor for OS only in older group (p = 0.690 vs p<0.001). Conclusion: In young breast cancer patients, less than 35 years, the impact of molecular subtypes on overall survival was not significant compared to other age group. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-42.

Effect of Axillary Lymph Node Dissection after Sentinel Lymph Node Biopsy on Overall Survival in Patients with T1 or T2 Node-positive Breast Cancer: Report from the Korean Breast Cancer Society

The effect of axillary lymph node dissection (ALND) after sentinel lymph node biopsy (SLNB) in patients with clinically node-negative patients in preoperative evaluations on overall survival (OS) is uncertain. The study aimed to evaluate the difference of survival between node-positive patients who underwent SLNB alone and those who received ALND after SLNB using the Korean Breast Cancer Society registry. We enrolled 2,581 patients who met the eligibility criteria. All enrolled patients had T1 or T2 breast cancer, and received mastectomy or breast-conserving treatment followed by documented adjuvant systemic therapy. There were 197 patients with SLNB alone and 2,384 patients with ALND after SLNB. Smaller tumor size, lower number of nodal metastasis, and higher proportion of breast-conserving surgery were found in patients with SLNB alone than in those with ALND after SLNB. There was no significant difference in OS between the two groups by the log-rank test. ALND after SLNB showed no significant improvement in OS in multivariate analysis. ALND in patients with sentinel metastasis who have T1 or T2 breast cancer receiving adjuvant systemic therapy may not have improved OS.

Korean Risk Assessment Model for Breast Cancer Risk Prediction

PurposeWe evaluated the performance of the Gail model for a Korean population and developed a Korean breast cancer risk assessment tool (KoBCRAT) based upon equations developed for the Gail model for predicting breast cancer risk.MethodsUsing 3,789 sets of cases and controls, risk factors for breast cancer among Koreans were identified. Individual probabilities were projected using Gail's equations and Korean hazard data. We compared the 5-year and lifetime risk produced using the modified Gail model which applied Korean incidence and mortality data and the parameter estimators from the original Gail model with those produced using the KoBCRAT. We validated the KoBCRAT based on the expected/observed breast cancer incidence and area under the curve (AUC) using two Korean cohorts: the Korean Multicenter Cancer Cohort (KMCC) and National Cancer Center (NCC) cohort.ResultsThe major risk factors under the age of 50 were family history, age at menarche, age at first full-term pregnancy, menopausal status, breastfeeding duration, oral contraceptive usage, and exercise, while those at and over the age of 50 were family history, age at menarche, age at menopause, pregnancy experience, body mass index, oral contraceptive usage, and exercise. The modified Gail model produced lower 5-year risk for the cases than for the controls (p = 0.017), while the KoBCRAT produced higher 5-year and lifetime risk for the cases than for the controls (p<0.001 and <0.001, respectively). The observed incidence of breast cancer in the two cohorts was similar to the expected incidence from the KoBCRAT (KMCC, p = 0.880; NCC, p = 0.878). The AUC using the KoBCRAT was 0.61 for the KMCC and 0.89 for the NCC cohort.ConclusionsOur findings suggest that the KoBCRAT is a better tool for predicting the risk of breast cancer in Korean women, especially urban women.

Weight Gain and its Correlates among Breast Cancer Survivors

Weight gain after diagnosis of breast cancer is a profound issue that may negatively impact cancer prognosis. However, most existing research on weight change has been conducted in Western countries. In addition, several factors related to weight gain have been reported; however, the evidence is inconsistent. The purpose of this study was to examine weight gain and its correlates among Korean breast cancer survivors. A total of 132 female breast cancer survivors were recruited from one university hospital in South Korea. Participants completed anthropometric measurements (i.e., body weight, height) and a self-reported questionnaire, including the International Physical Activity Questionnaire Short Form and Mini Dietary Assessment. The mean weight change was-0.09kg (SD=4.28). Only 27 women (19.7%) gained more than 5% of their weight at diagnosis, 59.1% maintained weight, and 21.2% lost weight. In multivariate logistic regression analysis, significant correlates of weight gain were younger age, obesity at diagnosis, duration of more than 36 months since diagnosis, and low diet quality. Younger women, women who were obese at diagnosis, women with more than 36 months since diagnosis, or women who showed lower diet quality should be considered at high-risk for weight gain. Findings from our study suggest that optimal weight management strategies should be developed using ethnically- or culturally-appropriate approaches.

Acute skin toxicity in Korean breast cancer patients carrying BRCA mutations

Purpose: In contrast to in vitro studies, most clinical trials testing the radiosensitivity of BRCA (Breast cancer susceptibility gene) mutations do not find a correlation between BRCA status and enhanced radiosensitivity. These trials include different ethnicities, and there is a lack of clinical data on BRCA1/2 mutation carriers and radiosensitivity in non-Caucasian patients. The goal of this study was to investigate acute skin toxicity, as a part of radiosensitivity, in breast cancer patients with BRCA1/2 mutations.Material and methods: BRCA mutation analysis was performed for 213 patients who underwent breast-conserving therapy using radiotherapy. Skin toxicity was scored according to the Radiation Therapy Oncology Group (RTOG) criteria during treatment and during one-month follow-up after radiation therapy.Results: Forty-six patients had BRCA1/2 mutations and 57 patients showed higher than grade 2 (RTOG) skin toxicity. In multivariate analysis, significant associations were found between mean breast volume and acute skin toxicity. BRCA mutation status, however, failed to show a significant correlation.Conclusions: Our results indicate that carriers of BRCA1/2 mutations among non-Caucasian breast cancer patients showed no enhancement in radiation sensitivity. Multiple genetic markers may be correlated with normal tissue responses after radiotherapy. Further studies are needed to identify genetic predispositions to normal tissue responses after radiotherapy.

Effect of multiple invasive foci on breast cancer outcomes according to the molecular subtypes: a report from the Korean Breast Cancer Society

BackgroundIn this study, the prognostic impact of the presence of the multifocal or multicentric tumor (MMT) and its association with molecular subtypes were investigated. Patients and methodsWe investigated the breast cancer metastasis and survival in patients with multifocal or multicentric invasive foci in the same breast. The study population includes 2882 patients in the Seoul National University Hospital Breast Care Center (SNUHBCC) dataset and 41 179 patients in Korean Breast Cancer Registry (KBCR) dataset. ResultsFrom SNUHBCC dataset, we observed a significant role of MMT in developing distant metastasis and death when the tumors were triple-negative subtype. This subtype-specific prognostic importance of MMT in overall survival was also seen in KBCR dataset (HR, 1.32; 95% CI, 1.02–1.69). In tumors <2 cm, the hazard ratios (HRs) for node metastasis and death were similar along the tumor size change in triple-negative subtype, while other subtypes showed a stepwise increment, suggesting the biologic importance of small invasive foci in this subtype. ConclusionsOur results demonstrate the prognostic importance of MMT in patients with triple-negative breast cancers. Small additional invasive foci in triple-negative breast cancer patients should be considered as clinically relevant tumor deposits.

Application of the Adjuvant! Online Model to Korean Breast Cancer Patients: An Assessment of Prognostic Accuracy and Development of an Alternative Prognostic Tool

Adjuvant! Online (AOL) is a Web-accessible risk-assessment model that predicts the mortality and the benefits of adjuvant therapy for breast cancer. Using the Yonsei Tumor Registry database, patients with T1-3, N0-3, M0 breast cancer who were treated at the Yonsei Cancer Center between 1986 and 1999 were entered into AOL version 8.0 to calculate survival. The median age of the study population was 45years (range, 23-76years) and the median follow-up duration was 10.8years (range, 0.1-25.9years) for all 699 patients. AOL significantly overestimated overall survival (OS) (by 11.1%, P<0.001), breast cancer-specific survival (BCSS) (by 11.6%, P<0.001), and event free-free survival (EFS) (by 9.25%, P<0.001) in Korean patients. Therefore, we developed a Korean version of AOL (KAOL), which is a new model for prognosis based on AOL's parameters. The observed 10-year OS (61.4%), BCSS (62.3%), and EFS (59.1%) and the KAOL predicted OS (61.5%), BCSS (63.5%) and EFS (57.6%) were not different (P=0.976, P=0.771, and P=0.674, respectively). AOL was not found to be suitable in Korean patients with breast cancer. The newly developed KAOL accurately predicted 10-year outcomes in Korean breast cancer patients.

Impact of local surgical treatment on survival in young women with T1 breast cancer: long-term results of a population-based cohort

The aim of this study was to analyze the effect of the type of local surgical treatment on survival in young women aged less than 40years with T1 breast cancer. We analyzed data from 3,512 patients aged ≤40years old who were diagnosed with T1 breast cancer from the Korean Breast Cancer Registry database between January 1988 and December 2006 and underwent either breast-conserving therapy (BCT) or mastectomy. The overall survival (OS) and breast-cancer-specific survival (BCSS) were compared between BCT and mastectomy. Of the 3,512 patients analyzed, 1,951 (55.6%) underwent BCT, and 1,561 (44.4%) underwent mastectomy. The median follow-up period was 111.0 (79.0-131.5)months. Overall, the 10-year OS rates for BCT and mastectomy were 95 and 92.1%, respectively (p=00004), and the 10-year BCSS rates for BCT and mastectomy patients were 96.9 and 94.9%, respectively (p=0.12). In node-negative patients, no significant difference was observed in either the OS (adjusted hazard ratio [HR] 1.072; 95% CI, 0.750-1.5332, p=0.704) or BCSS (adjusted HR 0.988; 95% CI, 0.620-1.574, p=0.960) rate between the BCT and mastectomy groups. In node-positive patients, no significant difference was observed in the OS (adjusted HR 1.634; 95% CI, 0.982-2.272, p=0.59) and BCSS (adjusted HR 1.410; 95% CI, 0.755-2.633, p=0.281) rates between the BCT and mastectomy groups. In this large, population-based analysis of young women with T1 breast cancer, the OS and BCSS were not different between BCT and mastectomy.

Toxicity and quality of life of Korean breast cancer patients treated with docetaxel-containing chemotherapy without primary G-CSF prophylaxis

The aim of this study was to evaluate the toxicity and quality of life (QoL) of breast cancer patients treated with a docetaxel-containing chemotherapeutic regimen and to compare adriamycin and cyclophosphamide (AC) for four cycles followed by docetaxel (D) for four cycles with docetaxel, adriamycin, and cyclophosphamide (TAC) for six cycles without primary granulocyte colony-stimulating factor (G-CSF) prophylaxis. Node-positive breast cancer patients who received surgery from three hospitals were included. Subjects received docetaxel-containing chemotherapy and completed a questionnaire on QoL (EORTC QLQ-C30 and QLQ-BR23) at each cycle. Toxicity was assessed using the National Cancer Institute Common Toxicity Criteria. All 78 eligible subjects and 542 cycles were analyzed. The incidence of dose reduction and grade 3 edema was higher in the AC-D group. The incidence of febrile neutropenia was significantly increased in the TAC group (63.4 %) compared to the AC-D group (29.7 %). Grade 3 or 4 anemia was higher in the TAC group, and grade 3 or 4 arthralgia was higher in the AC-D group. There were no significant differences in severe nausea and vomiting, fatigue, neuropathy, and peripheral edema. Baseline quality of life showed no difference between the two groups. The global health status decreased during chemotherapy and recovered to baseline level 3 months after chemotherapy. Although the incidence of febrile neutropenia was high without primary G-CSF prophylaxis and was more severe in the TAC group, QoL revealed comparable results in both regimens; therefore, it could be one of the considerations in the choice of treatment strategy.

Effect Modification of Hormonal Therapy by p53 Status in Invasive Breast Cancer

PurposeWe aimed to confirm the prognostic and predictive value of p53 expression, particularly in invasive breast cancer patients, according to immunohistochemical hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status.MethodsImmunohistochemical data for p53, estrogen receptor, progesterone receptor, and HER2 expression from a total of 15,598 patients were retrospectively retrieved from the web-based database of the Korean Breast Cancer Society. Overall survival (OS) and breast cancer-specific survival (BCSS) were calculated and compared using the Kaplan-Meier method and log-rank test, respectively. Multivariate analyses were performed using a stratified Cox proportional hazard regression model. A model evaluating interactions between p53 expression and both hormonal therapy and chemotherapy was used to determine the treatment benefit from both modalities.ResultsThe prognostic value of p53 for OS and BCSS was most significant in the HR+/HER2- subgroup, with hazard ratios of 1.44 (95% confidence interval [CI], 1.08-1.93) and 1.47 (95% CI, 1.09-1.99), respectively. The p53 overexpression hazard ratios were of borderline significance for the HR+/HER2+ subgroup and were not significant for the HR-/HER2+ and HR-/HER2- subgroups. The model with interaction terms revealed that hormonal therapy significantly interacts with p53 status (p=0.002 and p=0.007 for OS and BCSS, respectively), suggesting an insignificant prognostic value for p53 status (p=0.268 and p=0.296 for OS and BCSS, respectively). An interaction between chemotherapy and p53 status was not found in this model.Conclusionp53 overexpression has independent prognostic value, particularly in cases of HR+/HER2- invasive breast cancer, which may be due to effect modification of hormonal therapy dependent on p53 status.

Association of Human Epidermal Growth Factor Receptor 2 with Radiotherapy Resistance in Patients with T1N0M0 Breast Cancer

PurposePreclinical studies have shown that human epidermal growth factor receptor 2 (HER2) status is associated with resistance to radiotherapy (RT). In this study, we evaluated the overall survival of a T1N0M0 breast cancer cohort in Korea according to the use of RT and the HER2 status.MethodsWe analyzed data collected from 11,552 patients with invasive breast cancer who were enrolled in the Korean Breast Cancer Society Registration Program between 1999 and 2007. Data on the TNM stage, estrogen receptor status, progesterone receptor status, HER2 status, operation method, and the use of RT were analyzed.ResultsThe median follow-up period was 51 months. A significant improvement in overall survival after RT was observed only in the HER2(-) group. In this group, the 10-year overall survival rate was 95.5% for patients who did not receive RT and 96.3% for patients who received RT (p=0.037). In contrast, in the HER2(+) group, RT was not associated with a survival benefit (p=0.887). Multivariate analysis showed that RT was significantly associated with a reduction in mortality in the HER2(-) group (hazard ratio, 0.738; 95% confidence interval, 0.549-0.993; p=0.045).ConclusionWe found that postoperative RT was not associated with a survival benefit in HER2(+) breast cancer patients, suggesting that HER2(+) breast cancers could be RT resistant.

The Korean Version of the Body Image Scale-Reliability and Validity in a Sample of Breast Cancer Patients

ObjectiveThe Body Image Scale (BIS) developed in collaboration with the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Study Group is a brief questionnaire for measuring body image concerns in patients with cancer. This study sought to assess the reliability and validity of the Korean version of the Body Image Scale (K-BIS).MethodsThe participants consisted of 155 postoperative breast cancer patients (56 breast conserving surgery, 56 mastectomy, and 43 oncoplastic surgery). Subjects were evaluated using the K-BIS, the Body-Esteem Scale for Adolescents and Adults (BESAA), the Rosenberg Self-Esteem Scale (RSES), the Hospital Anxiety and Depression Scale (HADS), and the World Health Organization Quality of Life Scale Abbreviated Version (WHOQOL-BREF). Test-retest reliability and internal consistency were examined as a measure of reliability and validity was evaluated by convergent validity, discriminant validity and factor analysis.ResultsCronbach's α value was 0.943. The total score of the K-BIS was negatively correlated with the BESAA (r=0.301, p<0.001) and the body image facet in the WHOQOL-BREF (r=0.315, p<0.001). The total score of K-BIS positively correlated with the HADS (HAD-A: r=0.501, p<0.001, HAD-D: r=0.466, p<0.001). As for determining discriminant validity, scores were compared between the BCS subgroup, mastectomy subgroup, and oncoplastic surgery subgroup. Difference between the mastectomy subgroup and oncoplastic surgery subgroup was statistically significant (p=0.017). Factor analysis resulted in a single factor solution in three out of four anlyses, accounting for >59% variance.ConclusionThe K-BIS showed good reliability and validity for assessment of body image in Korean breast cancer patients.

Abstract P5-18-23: The prognosis of T1a, T1b N0 M0, HER2+ patients in Korea.

Abstract Backgrounds: Increased expression of HER-2 or amplification of the HER-2/neu gene has been associated with a worse prognosis than with other breast cancer phenotypes. Especially in cases of size of 0.5∼1cm and node-negative status, adjuvant chemotherapy with or without Trastuzumab treatment is suggested by recent National Comprehensive Cancer Network(NCCN) guidelines. In Korea, the breast cancer patient pool is more younger than western data, and there could be some ethnic differences. Methods: The Korean Breast Cancer Society (KBCS) has been collaborating with the Korean Central Cancer Registry (KCCR) to improve the completeness and validity of the breast cancer registry and the mortality data. Data of T1a, bN0M0 breast cancer patients from 1999 to 2006 from KBCS on-line registry was obtained, and a total of 2,962 patients were included for survival analysis. Results: 711 patients (24.0%) was HER-2 positive. Hormone receptor and HER2 status was used to classify 4 molecular subtypes; Hormone receptor(HR)+/HER2−, HR+/HER2+, HR−/HER2+, HR−/HER2−. The median follow-up was for 55.82 month (±24.196). Breast cancer specific survival rate was lowest at HR−/HER2+ subtype(97.9%). It's 1.0∼1.8% lower than other subtypes. Between all T1N0M0 cases, especially T1b HR−/HER2+ cases showed lowest survival of 96.4%. Conclusion: This study calculated the nationwide survival rates of Korean breast cancer patients with T1a, bN0M0 disease for the first time. HER2 gene positivity was associated with worse prognosis and it's concordant with western studies. But prognosis of T1N0M0 lesion is much better than that of other nations. So, the usage of chemotherapy and Trastuzumab treatment should be considered more carefully in Korea. Further analysis of the long-term survival and a nationwide collaborative study should be performed to estimate the survival trend of Korean breast cancer patients. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-18-23.

Lack of Either Estrogen or Progesterone Receptor Expression Is Associated with Poor Survival Outcome among Luminal A Breast Cancer Subtype

This study was designed to evaluate the impact of lack of either estrogen receptor (ER) or progesterone receptor (PR) on characteristics and outcomes among luminal A breast cancer subtype treated with endocrine with or without chemotherapeutic agents. The luminal A subtype was categorized into three subgroups: ER+/PR+, ER+/PR-, and ER-/PR+. All tumors were human epidermal growth factor receptor 2 (HER2) negative. Clinicopathological features and survival were analyzed using the Severance Hospital dataset (n = 1,180) and were validated by the nationwide Korean Breast Cancer Society (KBCS) registry (n = 9,916). Despite the different distribution of ER/PR status, tumor stage, grade, and local therapies between the two datasets, similarly ER+/PR+ showed smaller size and good differentiation, ER+/PR- patients had the oldest age at diagnosis, and ER-/PR+ was associated with the youngest age at onset and grade III tumor. Single hormone receptor-positive subgroups demonstrated worse disease-related outcomes than the ER+/PR+ subgroup. These associations were confirmed by the KBCS dataset. This trend was also demonstrated in the subpopulation of 1,944 patients with Ki-67 < 14 %. Inferior survival of single receptor-positive tumors was more definite among node-positive patients even when receiving both chemo-endocrine therapies. Current results suggest that the luminal A subtype is also heterogeneous and each subgroup has unique clinicopathologic characteristics. Lack of either ER or PR expression is associated with worse survival, especially among node-positive luminal A subtype.

Abstract B95: Higher breast density is positively associated with larger tumor size and lymph node metastasis: A cross-sectional study of 910 Korean breast cancer patients

Abstract Although many western studies have demonstrated high breast density as a strong risk factor for breast cancer, it is poorly understood whether breast density differentially affects the diverse phenotypes of breast cancer. We examined the association between various tumor characteristics and mammographic breast density in women with breast cancer. We conducted a cross-sectional analysis in 910 Korean women diagnosed with in situ or invasive breast cancer to evaluate the associations between breast density and tumor size, lymph node (LN) status, lymphatic or vascular invasion, histologic grade, estrogen receptor (ER), progesterone receptor (PR), HER2, p53, and CK5/6. Breast density was classified as fatty (percent density less than 50% by a computer-assisted thresholding program, named “Cumulus TM”; n = 470) or dense (percent density 50% or more; n = 440) for the cancer-free breast at the time of operation. A single pathologist measured all tumor markers. Blinded to the tumor markers' status, percent densities were also calculated by a single rater. Logistic regression was used to examine whether the relationships were modified by adjustment for body mass index, age at diagnosis, age at first birth, menopausal status, history of breast-feeding, and breast cancer staging. The mean age was 48 (range 20-82) years old and mean percent density was 49.1% (SD = 15.2%: normally distributed, Kolmogorov-Smirnov test p=0.32). Women with a tumor size &amp;gt;0.5cm were more likely to have dense breasts compared with women with a tumor size &amp;lt;=0.5 cm (ORadj = 4.2, 95% CI = 1.6-11.2 for tumor sizes 0.6-1.0cm; ORadj = 3.4, 95% CI = 1.4-8.2 for tumor sizes 1.1-1.5cm; ORadj = 3.3, 95% CI = 1.4-7.9 for tumor sizes 1.6-2.0cm; and ORadj = 2.0, 95% CI = 0.7-5.5 for tumor sizes 2.1cm or more). An association between LN positivity and percent density had borderline significance (ORadj = 1.8, 95% CI = 0.997-3.215 for positive LN status). Percent density was not significantly associated with lymphatic or vascular invasion (p = 0.77), ER (p = 0.39), PR (p = 0.83), HER2 (p = 0.40), p53 (p=0.22), and CK5/6 (p = 0.62). An inverse association was suggested between tumor grade and percent density (OR = 0.56, 95% CI = 0.33-0.97), but insignificant after the adjustment (ORadj = 0.65, 95% CI = 0.31-1.37). These results suggest that breast density is associated with tumor size and LN status. Additional studies are needed to address whether these associations are due to just density masking the detection of some tumors, biological causation, or both. Citation Format: Jong won Lee, Ja Young Cho, Sei-hyun Ahn. Higher breast density is positively associated with larger tumor size and lymph node metastasis: A cross-sectional study of 910 Korean breast cancer patients. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr B95.

Factors influencing health-promoting behaviors in Korean breast cancer survivors

PurposeThe purpose of this study was to examine the relationships among internal health locus of control, depression, social support, and health-promoting behaviors in Korean breast cancer survivors and to identify factors influencing health-promoting behaviors. MethodA predictive design was used. The data were collected by questionnaires from a convenience sample of 258 breast cancer survivors in Korea during 2007. The data were analyzed using descriptive statistics, t-tests, one-way ANOVA, Pearson's correlation coefficients, and stepwise multiple regression. ResultsWhen differences of health-promoting lifestyle based on demographic and illness-related characteristics were examined, no significant differences were found except for undergoing chemotherapy. Internal health locus of control, depression, and social support were correlated significantly with the health-promoting lifestyle. As a result of stepwise multiple regression analysis, social support, depression, and chemotherapy were discovered to account for 34.98% of the variance in health-promoting lifestyle. The variable that most affected a health-promoting lifestyle was social support, followed by chemotherapy and depression. ConclusionsThe results of the study clearly demonstrate the importance of social support and depression in explaining the occurrence of a health-promoting lifestyle among Korean breast cancer survivors.

Evaluation of the willingness‐to‐pay for cancer treatment in Korean metastatic breast cancer patients: A multicenter, cross‐sectional study

To evaluate the inherent value of breast cancer therapy a willingness-to-pay (WTP) study was conducted in Korean patients with metastatic breast cancer. Patients were prospectively enrolled from four study centers and completed quality of life questionnaires to reflect their status pre-cancer and their current health status. Clinical and socioeconomic data were collected to characterize the population and utilize during modeling. Patients' WTP for breast cancer treatment was assessed using an open-ended question following three rounds of bidding to better hone in on their maximal WTP, starting with one of three randomly assigned start bids. Predictors of patient WTP was evaluated using linear regression models. Associations between WTP and other parameters were evaluated with correlations. Korean metastatic breast cancer patients were WTP an average of KRW 8 696 329 (US$7555) per month to return to their pre-cancer health state, with those who were recently diagnosed as WTP the most (KRW 12 955 000 [$11 254]). WTP was closely associated with the patient's education level, income, personal financial difficulties, Eastern Cooperative Oncology Group performance status, and their experience of arm symptoms. The results suggest that patients are WTP significant amounts per month for treatment. Breast cancer patients are heavily burdened physically, mentally and financially, and the present study indicated this significant financial burden by disclosing its relationship with WTP. Providing a better understanding of the inherent value of treatment will allow Koreans to better evaluate treatment in the coming era of personalized medicine.

Perception, Attitudes, Preparedness and Experience of Chemotherapy-Induced Alopecia among Breast Cancer Patients: a Qualitative Study

Regardless of its negative impact on quality of life, little is known about the importance of alopecia from the patients' perspective. This study aimed to explore the whole experience of chemotherapy- induced alopecia among Korean breast cancer patients including perception, attitudes, preparedness, and changes after alopecia. Patients expected to experience or had experienced alopecia were recruited at a tertiary hospital in Seoul, Korea. Semi-structured in-depth interviews were performed in 21 patients. Recurrent issues were identified and placed into thematic categories. All patients think that appearance is important and they pay attention to how they look like. They had negative perceptions about alopecia. Patients were not well prepared for alopecia, and experienced substantial physical, psychological and social distress. Lack of information and limited social support combined with negative images of cancer made it difficult for patients to overcome the trauma and deterred them from usual daily activities resulting in poor quality of life. Patients were not well prepared for alopecia and negative perceptions, lack of preparedness, and limited social support and resources increased alopecia- related distress. Educational programs for preparing patients to cope with alopecia distress and advocate activities to change people's negative perception about alopecia are needed to reduce the burden imposed by alopecia in cancer patients.

Accuracy of BRCA1/2 mutation prediction models in Korean breast cancer patients

BRCAPRO and Myriad II are widely used models for predicting BRCA1/2 mutation probability before genetic testing. However, the accuracy of these models in Koreans is not known. This study was performed to evaluate the accuracy of the BRCAPRO and Myriad II models. Two hundred thirty-six women with breast cancer who underwent comprehensive BRCA1/2 genetic testing at our hospital between 2003 and 2010 were included in this study. We evaluated the performance of each model by comparing the numbers of observed versus predicted mutation carriers. We calculated sensitivity, specificity, and predictive values at 10 % estimated probability. Forty-six individuals were identified to carry a deleterious BRCA mutation. The prevalence of BRCA mutation (19.5 %) was significantly higher than that predicted by BRCAPRO (9.0 %, p = 0.001) and Myriad (5.6 %, p < 0.001). In familial breast cancer patients, BRCA mutation rate (observed 22.7 %) was underestimated by both BRCAPRO (expected 11.4 %, p = 0.006) and Myriad II (expected 6.4 %, p < 0.001). Subgroup analyses showed that both models underestimated the risk of BRCA mutation in patients with a family history of breast cancer (probands' age at breast cancer diagnosis >50 years), with only one relative with breast cancer, and with non-familial early-onset breast cancer or bilateral breast cancer. Using a 10 % cut-off, the sensitivities were 47.8 % (BRCAPRO) and 50.0 % (Myriad), and positive predictive values were 44.9 % (BRCAPRO) and 43.4 % (Myriad). Both BRCAPRO and Myriad II underestimated the risk of BRCA1/2 mutation in Koreans. Our findings suggest that these models are less sensitive in Korean women, and therefore a new BRCA mutation prediction model based on Korean data is needed for proper genetic counseling.

Prevalence of BRCA1 and BRCA2 mutations in non-familial breast cancer patients with high risks in Korea: The Korean Hereditary Breast Cancer (KOHBRA) Study

Prevalence and phenotype of BRCA mutation can vary by race. The purpose of this study is to evaluate the prevalence of BRCA1/2 mutations in non-familial breast cancer patients with high risks in Korea. A subset of 758 patients was selected for this study from the KOHBRA nationwide multicenter prospective cohort study. Mutations in BRCA1/2 genes were tested using fluorescent-conformation sensitive gel electrophoresis, denaturing high performance liquid chromatography or direct sequencing. Mutation of BRCA1/2 genes were identified in 65 (8.6%) patients among total 758 patients [BRCA1 mutation: 25 (3.3%), BRCA2 mutation: 40 (5.3%)]. According to risk groups, mutation of BRCA1/2 genes were identified in 53 (8.5%) of 625 early onset patients (age ≤40), in 22 (17.7%) of 124 bilateral breast cancer patients, in 3 (50.0%) of 6 breast and ovarian cancer patients, in one (5.9%) of 17 male breast cancer patients, in 5 cases (7.6%) of 66 multiple organ cancer patients. The most common mutation was 509C>A for BRCA1 and 7708C>T for BRCA2. The prevalence of BRCA1/2 mutations by age in early onset patients was significantly different (age <35 vs age ≥35; 10.0 vs 2.9%, p = 0.0007). BRCA1/2 mutations for non-familial Korean breast cancer patients were detected at a high rate, particularly, in patients with early onset of less than 35 years of age, bilateral breast cancer, and breast and ovarian cancer. Individualized genetic counseling should be offered for non-familial breast cancer patients with these risk factors.