The Basic Facts of Korean Breast Cancer in 2013: Results of a Nationwide Survey and Breast Cancer Registry Database

Assessment of hair loss and skin changes during treatment in Asian breast cancer patients: A prospective cohort study

With the increasing number of young breast cancer (BC) patients worldwide, concerns about hair loss and skin change persist among BC survivors. This study aimed to evaluate the hair loss and skin changes in Asian BC patients and to compare them according to the treatment regimens. This study enrolled 322 patients scheduled to undergo BC surgery. Hair loss and skin changes were assessed at the following two time points: one day before surgery and 6 months after surgery. Patients who had received systemic anticancer treatment before surgery were assigned to the neoadjuvant treatment group, while patients who were scheduled to receive systemic anticancer treatment were assigned to the adjuvant treatment group. In the adjuvant treatment group, patients with taxane-based chemotherapy had significantly higher odds of increased hair loss, a higher melanin index, and an increased volume of wrinkles (p < 0.0001, p = 0.0110, and p = 0.0371, respectively). In the neoadjuvant treatment group, hair loss was reversed in most patients at 6 months after surgery. Clinicians should inform BC patients about the potential for hair loss and skin changes and provide supportive care to mitigate the effects on the patients' quality of life.

Comprehensive Young Age Breast Cancer registry from clinical, genomics, and patient-reported outcomes measured with 15 years follow-up: the CHARM cohort profile

BACKGROUND

In recognition of the distinct clinical challenges and research gaps in young breast cancer (YBC) patients, we established the Comprehensive Young Age Breast Cancer (CHARM) registry to collect prospective data.

METHODS

This prospective cohort included patients who were newly diagnosed with histologically confirmed breast cancer without prior treatment at the Samsung Medical Center (SMC) in April 2013. We included patients who were either 40 years old or younger at the time of diagnosis, pregnant at breast cancer diagnosis or diagnosed with breast cancer within 1 year of delivery. All data were collected using Medidata's Rave Electronic Data. Clinical data were obtained from electronic medical records. Two experienced pathologists reviewed the pathologic data. Bone mineral densitometry tests have been conducted annually. To obtain multi-omics data, tumor tissues and blood samples were prospectively collected from consenting patients in the registry during surgery. The fertility-related factor also collected collaborated with the Department of Obstetrics and Gynecology. Anti-Müllerian hormone, estradiol, follicle-stimulating hormone, and luteinizing hormone levels were measured using an additional blood sample from baseline to last follow-up. Patient-reported outcomes were assessed using mobile questionnaires.

RESULTS

A total of 1868 participants were included in the SMC YBC study. The average (standard deviation) age was 35.57 (3.79) and 99.8% of the participants were premenopausal. Among them, 1062 participants completed the PRO questionnaires.

CONCLUSIONS

The SMC YBC cohort serves as a comprehensive registry for YBC to optimize care and improve knowledge regarding the management of YBC.

Characteristics and chronologically changing patterns of late-onset breast cancer in Korean women of age ≥ 70 years: A hospital based-registry study

BACKGROUND

Women from Asian and western countries have vastly different ages of onset of breast cancer, with the disease tending to occur at an older age in the West. Through an investigation of the patterns of old-onset breast cancer (OBC) in Korean women, we aimed to identify the characteristics of Korean OBC and evaluate whether these patterns are changing in relation to increasing westernization.

METHODS

This study retrospectively evaluated 102,379 patients who underwent surgical treatment of primary breast cancer between January 1, 2000 and December 31, 2013 in Korea. We used hospital -based breast cancer registry and analyzed data from these patients using multiple linear regression analysis to compare the characteristics and chronologically changing patterns between OBC (70 years of age or older) and non-OBC (40-69 years of age) patients in Korea.

RESULTS

A total of 6% of the 102,379 patients had OBC. Overall, OBC had more favorable biological features, such as a higher incidence of luminal A subtype, than did non-OBC, except for a higher incidence rate of triple-negative breast cancer (TNBC). However, OBC also presented with a higher overall disease stage, including higher T and M stages. Although the incidence rates of both OBC and non-OBC have increased overtime, the relative proportion of OBC patients has slightly increased, whereas that of non-OBC has slightly decreased. The increase in the incidence of both OBC and non-OBC was primarily due to the luminal A subtype.

CONCLUSIONS

Based on a hospital-based registry, overall, Korean OBC had favorable biological features but showed a higher rate of TNBC and advanced cancer stages. The incidence trend of breast cancer in Korea is slowly shifting toward an older age at onset, largely due to the luminal A subtype. Our results may provide novel insights into OBC in Asia, and aid in the development of optimal management of the disease in Asia.

TRIAL REGISTRATION

Retrospectively registered.

The different prognostic impact of age according to individual molecular subtypes in breast cancer

Purpose

Young age at diagnosis has been considered a poor prognostic factor. However, considering young age itself as an independent poor prognostic factor for all breast cancers is unwarranted. We analyzed the different prognostic effects of age as a prognostic factor according to molecular subtype.

Methods

We retrieved data from 1,819 patients with primary breast cancer at the breast cancer center between 2007 and 2012. We classified each molecular subtype in 3 age cohorts (<40, 40–50, and >50 years). The associations of age and molecular subtypes with relapse-free survival (RFS) and disease-specific survival (DSS) were assessed.

Results

Patients aged <40 years showed a poor histologic grade, hormone receptor negative expression than older patients, and had a higher proportion of triple-negative breast cancer (TNBC) (P < 0.001). This was thought to have led to a significantly shorter RFS than that of older patients (P < 0.001). In the subgroup analysis according to molecular subtypes, the poorer RFS was observed only in patients aged <40 years with luminal type breast cancer (P < 0.001). Age was an independent prognostic factor of RFS in luminal-type breast cancer (P = 0.001). However, no difference in RFS between age groups was found for patients with other subtypes (human epidermal growth factor receptor 2 overexpression, TNBC). No significant effect between age groups was found in DSS for patients with all molecular subtypes.

Conclusion

Age at diagnosis of breast cancer affected prognosis differently according to molecular subtype. Age itself is not an independent prognostic factor. Age of <40 years showed a limited worse prognostic impact of recurrence in luminal type breast cancer only.

Relationship between the type of hormone replacement therapy and incidence of breast cancer in Korea

OBJECTIVE

This study aimed to investigate the relationship between hormone replacement therapy (HRT) types and breast cancer (BC) incidence in postmenopausal women in Korea.

METHODS

The nested case-control study used data from the National Health Insurance Service database. Among the women aged ≥50 years who menopaused between 2004 and 2007, BC incidence up to 2017 was analyzed in 36,446 women using or having used HRT for >1 year and in 36,446 women who did not use any HRT for more than 1 year. HRT types and duration were classified into three categories.

RESULTS

BC risk (BCR) decreased with tibolone use for all ages. With HRT initiation in women aged ≥50 years, BCR was lower with tibolone and estrogen-progestogen therapy. HRT for <3 years showed lower BCR with tibolone, while higher BCR was observed with estrogen-only therapy. BCR was lower in women of all ages on HRT for >5 years than in the control group.

CONCLUSIONS

For women in their 50s, tibolone use lowers BCR; for all ages, the use of any HRT for >5 years showed lower BCR in Korea. These divergent results from western countries could be associated with the specific characteristics of BC in Korea.

Low incidence of lymph node metastasis in patients with microinvasive breast cancer: a Korean nationwide study

Purpose

Microinvasive breast cancer (MIBC) is an invasive carcinoma with a tumor dimension not exceeding 1 mm. Owing to its low incidence, the rate of axillary node metastasis and its management are not well established. The aim of this study was to assess the incidence of lymph node metastasis (LNM) and identify variables associated with LNM, as well as to evaluate the need for axillary staging in MIBC patients by analyzing nationwide data.

Methods

The Korean Breast Cancer Society registry was searched to identify MIBC patients diagnosed between January 1996 and April 2020. Patients without neoadjuvant chemotherapy experiences, systemic metastasis, and missing or discordant data were eligible for the analysis. The incidence rate of LNM was determined, and variables associated with LNM were identified by multivariable regression analysis.

Results

Of 2,427 MIBC patients identified, 98 (4.0%) had LNM and 12 (0.5%) had N2/3 disease. Type of breast operation (odds ratio [OR], 2.093; 95% confidence interval [CI], 1.332–3.290; P = 0.001), age (OR, 2.091; 95% CI, 1.326–3.298; P = 0.002), hormone receptor status (OR, 2.220; 95% CI, 1.372–3.594; P = 0.001), and lymphovascular invasion (OR, 11.143; 95% CI, 6.354–19.540; P < 0.001) were significantly related to LNM.

Conclusion

The incidence of LNM in MIBC patients was only 4.0% in our study, suggesting that de-escalation of axillary surgical interventions could be carefully considered. The indications for axillary staging should be individualized considering tumor volume, age, hormone receptor status, and lymphovascular invasion to improve the quality of life of MIBC survivors.

Comparison of clinicopathological characteristics and prognosis in breast cancer patients with different Breast Imaging Reporting and Data System categories

Purpose

The Breast Imaging Reporting and Data System (BI-RADS) is a systematic and standardized scheme of the radiological findings of breast. However, there were different BI-RADS categories between breast cancers as the clinical characteristics in previous studies. We analyzed the association of BI-RADS categories with the clinicopathological characteristics and prognosis of breast cancer.

Methods

A total of 44,184 patients with invasive breast cancers assigned to BI-RADS category 3, 4, or 5 in preoperative mammography or ultrasonography were analyzed retrospectively using large-scale data from the Korean Breast Cancer Society registration system. The difference in the clinicopathological factors and prognoses according to the BI-RADS categories (BI-RADS 3–4 and BI-RADS 5) were compared between the mammography and ultrasonography groups. Comparisons of the clinicopathological factors in both groups were made using logistic regression analysis, while the prognoses were based on the breast cancer-specific survival using the Kaplan-Meier method and Cox proportional hazards model.

Results

The factors associated with BI-RADS were T stage, N stage, palpability, histology grade, and lymphovascular invasion in the mammography group; and N stage, palpability, histology grade, and lymphovascular invasion in the ultrasonography group. In the survival analysis, there were significant differences in the breast cancer-specific survival of the BI-RADS category groups in both of the mammography (hazard ratio [HR], 3.366; P < 0.001) and ultrasonography (HR, 2.877; P < 0.001) groups.

Conclusion

In this study, the BI-RADS categories of preoperative mammography and ultrasonography of patients with invasive breast cancer were associated with prognosis and could be an important factor in making treatment decisions.

Body mass index and type 2 diabetes and breast cancer survival: a Mendelian randomization study

The causal relationship between body mass index (BMI) and type 2 diabetes (T2D) and breast cancer prognosis is still ambiguous. The aim of this study was to investigate the prognostic effect of BMI and T2D on breast cancer disease-free survival (DFS) among Asian individuals. In this two-sample Mendelian randomization (MR) study, the instrumental variables (IVs) were identified using a genome-wide association study (GWAS) among 24,000 participants in the Taiwan Biobank. Importantly, the validity of these IVs was confirmed with a previous large-scale GWAS (Biobank Japan Project, BBJ). In this study, we found that a genetic predisposition toward higher BMI (as indicated by BMI IVs, F = 86.88) was associated with poor breast cancer DFS (hazard ratio [HR] = 6.11; P < 0.001). Furthermore, higher level of genetically predicted T2D (as indicated by T2D IVs) was associated with an increased risk of recurrence of and mortality from breast cancer (HR = 1.43; P < 0.001). Sensitivity analyses, including the weighted-median approach, MR-Egger regression, Radial regression and Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) supported the consistency of our findings. Finally, the causal relationship between BMI and poor breast cancer prognosis was confirmed in a prospective cohort study. Our MR analyses demonstrated the causal relationship between the genetic prediction of elevated BMI and a greater risk of T2D with poor breast cancer prognosis. BMI and T2D have important clinical implications and may be used as prognostic indicators of breast cancer.

Changes in Korean National Healthcare Insurance Policy and Breast Cancer Surgery Trend in Korea

BACKGROUND

Since April 2015, the Korean National Health Insurance (NHI) has reimbursed breast cancer patients, approximately 50% of the cost of the breast reconstruction (BR) procedure. We aimed to investigate NHI reimbursement policy influence on the rate of immediate BR (IBR) following total mastectomy (TM).

METHODS

We retrospectively analyzed breast cancer data between April 2011 and June 2016. We divided patients who underwent IBR following TM for primary breast cancer into "uninsured" and "insured" groups using their NHI statuses at the time of surgery. Univariate analyses determined the insurance influence on the decision to undergo IBR.

RESULTS

Of 2,897 breast cancer patients, fewer uninsured patients (n = 625) underwent IBR compared with those insured (n = 325) (30.0% vs. 39.8%, P < 0.001). Uninsured patients were younger than those insured (median age [range], 43 [38-48] vs. 45 [40-50] years; P < 0.001). Pathologic breast cancer stage did not differ between the groups (P = 0.383). More insured patients underwent neoadjuvant chemotherapy (P = 0.011), adjuvant radiotherapy (P < 0.001), and IBR with tissue expander insertion (P = 0.005) compared with those uninsured.

CONCLUSION

IBR rate in patients undergoing TM increased after NHI reimbursement.

Pre-Menopausal Women With Breast Cancers Having High AR/ER Ratios in the Context of Higher Circulating Testosterone Tend to Have Poorer Outcomes

Purpose

Women with breast tumors with higher expression of AR are in general known to have better survival outcomes while a high AR/ER ratio is associated with poor outcomes in hormone receptor positive breast cancers mostly in post menopausal women. We have evaluated the AR/ER ratio in the context of circulating androgens specifically in patients younger than 50 years most of whom are pre-menopausal and hence have a high estrogenic hormonal milieu.

Methods

Tumor samples from patients 50 years or younger at first diagnosis were chosen from a larger cohort of 270 patients with median follow-up of 72 months. Expression levels of ER and AR proteins were detected by immunohistochemistry (IHC) and the transcript levels by quantitative PCR. Ciculating levels of total testosterone were estimated from serum samples. A ratio of AR/ER was derived using the transcript levels, and tumors were dichotomized into high and low ratio groups based on the third quartile value. Survival and the prognostic significance of the ratio was compared between the low and high ratio groups in all tumors and also within ER positive tumors. Results were further validated in external datasets (TCGA and METABRIC).

Results

Eighty-eight (32%) patients were ≤50 years, with 22 having high AR/ER ratio calculated using the transcript levels. Circulating levels of total testosterone were higher in women whose tumors had a high AR/ER ratio (p = 0.02). Tumors with high AR/ER ratio had significantly poorer disease-free survival than those with low AR/ER ratio [HR-2.6 (95% CI-1.02-6.59) p = 0.04]. Evaluation of tumors with high AR/ER ratio within ER positive tumors alone reconfirmed the prognostic relevance of the high AR/ER ratio with a significant hazard ratio of 4.6 (95% CI-1.35-15.37, p = 0.01). Similar trends were observed in the TCGA and METABRIC dataset.

Conclusion

Our data in pre-menopausal women with breast cancer suggest that it is not merely the presence or absence of AR expression but the relative activity of ER, as well as the hormonal milieu of the patient that determine clinical outcomes, indicating that both context and interactions ultimately influence tumor behavior.

Breast Cancer Statistics in Korea, 2018

Breast cancer is the most common malignancy in Korean women, and its incidence continues to increase. The Korean Breast Cancer Society (KBCS) established a nationwide breast cancer database through its online enrollment program in 1996. This study aimed to analyze the clinical characteristics of breast cancer in Korea, and to assess the pattern of changes in breast cancer management in 2018. We analyzed the KBCS and Korea Central Cancer Registry (KCCR) databases in 2018. In 2018, 28,157 patients were newly diagnosed with breast cancer, of whom 4,510 had noninvasive breast cancer and 23,647 had invasive breast cancer. The age-standardized rate of breast cancer in 2018 was 79.0 per 100,000 women (65.6 invasive, 13.4 noninvasive). The median age of female patients diagnosed with breast cancer in 2018 was 52 years, and the incidence of breast cancer was the highest in the 40–49-years age group (9,432 patients, 33.6%). The proportion of patients with stage 0 and stage I breast cancer continued to increase, accounting for 63.8% of cases, and breast-conserving surgery was performed more often than mastectomy (66.2% vs. 33.0%). The most common subtypes of breast cancer were hormone receptor [HR]-positive and human epidermal growth factor receptor-2 (HER2)-negative types (65.9% of cases), while the HR-negative and HER2-positive types accounted for 9.2% of cases. According to the KCCR data, from 2014 to 2018, the 5-year relative survival rate of patients with breast cancer was 93.3%, which was 14.0% higher than that from 1993 to 1995 (79.3%). The clinical characteristics of breast cancer in Korea have been changing, and national databases can improve our understanding of the disease characteristics of Korean women. Therefore, updating the KBCS registry is important for the effective management of breast cancer in Korea.

Effect of Treatment with the PD-1/PD-L1 Inhibitors on Key Health Outcomes of Cancer Patients

BACKGROUND

Recent studies have shown that treatment with the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitor class could significantly improve survival outcomes in several oncology indications. However, there is some clinical uncertainty.

OBJECTIVE

This study aimed to obtain high-level estimates of the impact of treatment with PD-1/PD-L1 inhibitor class to oncology treatment on key health outcomes in real-world situations and to inform public health policy decisions about cancer care after reducing uncertainties around new immuno-oncology therapy options in South Korea.

METHODS

A model was developed to estimate the impact of PD-1/PD-L1 inhibitors on outcomes in situations wherein both anti-PD-1/PD-L1s and standard of care (SOC) were available versus SOC only. A partitioned survival model was utilized to estimate the impact of introducing anti-PD-1/PD-L1s on outcomes, including life-years gained, quality-adjusted life-years gained, progression-free survival-years obtained, and grade 3 or higher adverse events avoided for six indications over 5 years. An exponential distribution was fitted to the survival function of the SOC based on visual inspection. Outcomes associated with anti-PD-1/PD-L1s were estimated using a piecewise modeling approach with Kaplan-Meier analysis followed by best-fitting survival analysis. The incident number of patients and market share of anti-PD-1/PD-L1s during 2020-2024 were projected using published literature and Korean market survey data. Sensitivity analyses were performed to test the uncertainty of input parameters.

RESULTS

During the next 5-year period (2020-2024), introducing the anti-PD-1/PD-L1 class led to a gain of 22,001 life-years (+ 31%), 19,073 quality-adjusted life-years (+ 38%), and 22,893 progression-free survival-years (+ 82%); it also avoided 3610 adverse events (- 11%) compared with SOC alone. Most adverse events associated with anti-PD-1/PD-L1s were attributed to combination therapy with cytotoxic chemotherapy (91%). In a scenario wherein the time to reimbursement of the anti-PD-1/PD-L1s was accelerated by 1 year, the life-years gained increased by 14% compared with the base-case scenario.

CONCLUSIONS

Anti-PD-1/PD-L1 therapy is expected to provide marked survival benefits for patients with cancer. This study demonstrated the potentially beneficial health impacts of utilizing the anti-PD-1/PD-L1 class at the population level. The findings could inform health policy decision makers about cancer care and ultimately enhance population health through rapid access to innovative cancer drugs.

Post-mastectomy radiation therapy in breast reconstruction: a patterns of care study of the Korean Radiation Oncology Group

PURPOSE

The details of breast reconstruction and radiation therapy (RT) vary between institutions; therefore, we sought to investigate the practice patterns of radiation oncologists who specialize in breast cancer.

MATERIALS AND METHODS

We identified the practice patterns and inter-hospital variations from a multi-center cohort of women with breast cancer who underwent post-mastectomy RT (PMRT) to the reconstructed breast at 16 institutions between 2015 and 2016. The institutions were requested to contour the target volume and produce RT plans for one representative case with five different clinical scenarios and answer questionnaires which elicited infrastructural information. We assessed the inter-institutional variations in RT in terms of the target, normal organ delineation, and dose-volume histograms.

RESULTS

Three hundred fourteen patients were included; 99% of them underwent immediate reconstruction. The most irradiated material was tissue expander (36.9%) followed by transverse rectus abdominis musculocutaneous flap (23.9%) and silicone implant (12.1%). In prosthetic-based reconstruction with tissue expander, most patients received PMRT following partial deflation. Conventional fractionation and hypofractionation RT were used in 66.6% and 33.4% patients, respectively (commonest: 40.05 Gy in 15 fractions [17.5%]). Furthermore, 15.6% of the patients received boost RT and 53.5% were treated with bolus. Overall, 15 physicians responded to the questionnaires and six submitted their contours and RT plans. There was a significant variability in target delineations and RT plans between physicians, and between clinical scenarios.

CONCLUSION

Adjuvant RT following post-mastectomy reconstruction has become a common practice in Korea. The details vary significantly between institutions, which highlights an urgent need for standard protocol in this clinical setting.

Prognosis of BRCA1/2-negative breast cancer patients with HBOC risk factors compared with sporadic breast cancer patients without HBOC risk factors

OBJECTIVE

Demands for genetic counseling with BRCA1/2 examination have markedly increased. Accordingly, the incidence of uninformative results on BRCA1/2 mutation status has also increased. Because most patients examined for BRCA1/2 mutation have a high risk of hereditary breast and/or ovarian cancer, many patients suffer psychological distress even when the BRCA1/2 result is negative. We compared oncological outcomes between BRCA1/2-negative breast cancer with high risk of hereditary breast and/or ovarian cancer and sporadic breast cancer without risk of hereditary breast and/or ovarian cancer.

METHODS

The criteria for high risk for hereditary breast and/or ovarian cancer were defined as family history of breast and/or ovarian cancer in first- or second-degree relative, early onset breast cancer at <35 years old and bilateral breast cancer. Patients were matched maximally 1:3 into those who identified as negative for BRCA1/2 mutation with risk of hereditary breast and/or ovarian cancer (study group) and those who were not examined for BRCA1/2 mutation without risk for hereditary breast and/or ovarian cancer (control group). Matched variables were pathologic stage, estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2 status.

RESULTS

All matching variables were successfully matched. Median follow-up duration was 57.8 months. There was no significant difference between the groups in disease-free survival (log-rank P = 0.197); however, the study group showed significantly better overall survival and breast cancer-specific survival (both P < 0.0001). We conducted subgroup analysis in the middle-aged group (36-54) and showed no significant difference for disease-free survival (P = 0.072) but significantly better overall survival and breast cancer-specific survival in the study group (P = 0.002 and P < 0.0001).

CONCLUSIONS

BRCA1/2-negative breast cancer patients who had hereditary breast and/or ovarian cancer risk factors showed similar disease-free survival and better overall survival and breast cancer-specific survival compared with those with sporadic breast cancer without hereditary breast and/or ovarian cancer risk factors.

A N0 Predicting Model for Sentinel Lymph Node Biopsy Omission in Early Breast Cancer Upstaged From Ductal Carcinoma in Situ

BACKGROUND

A prediction model with high sensitivity for the detection of negative axillary involvement can reduce additional axillary surgery in patients with ductal carcinoma in situ (DCIS) upstaged to invasive cancer while saving patients with pure DCIS from unnecessary axillary surgeries. Using a nationwide database, we developed and validated a scoring system for guidance in selective sentinel lymph node biopsy omission.

PATIENTS AND METHODS

A total of 41,895 patients with clinically node-negative breast cancer from the Korean Breast Cancer Registry were included. The study cohort was randomly divided for the development and validation of the prediction model. Missing data were filled in using multiple imputation. Factors that were significantly associated with axillary lymph node (ALN) metastasis in > 50% of datasets were included in the final prediction model.

RESULTS

The frequency of ALN metastasis in the total cohort was 24.5%. After multivariable logistic regression analysis, variables that were associated with ALN metastasis were palpability, multifocality, location, size, histologic type, grade, lymphovascular invasion, hormone receptor expression, and Ki-67 level. A scoring system was developed using these factors. The areas under the receiver operating characteristic curve for the scoring system was 0.750 in both training and validating sets. The cutoff value for performing sentinel lymph node biopsy was determined as a score of 4 to obtain prediction sensitivity higher than 95%.

CONCLUSIONS

A scoring system to predict the probability of ALN metastasis was developed and validated. The application of this system in the clinic may reduce unnecessary axillary surgeries in patients with DCIS and minimize additional axillary surgery for upstaged patients with invasive cancer.

Comparison of GenesWell BCT Score With Oncotype DX Recurrence Score for Risk Classification in Asian Women With Hormone Receptor-Positive, HER2-Negative Early Breast Cancer

Introduction: The GenesWell Breast Cancer Test (BCT) is a recently developed multigene assay that predicts the risk of distant recurrence in patients with early breast cancer. Here, we analyzed the concordance of the BCT score with the Oncotype DX recurrence score (RS) for risk stratification in Asian patients with pN0-N1, hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

Methods: Formalin-fixed, paraffin-embedded breast cancer tissues previously analyzed using the Oncotype DX test were assessed using the GenesWell BCT test. The risk stratification by the two tests was then compared.

Results: A total of 771 patients from five institutions in Korea were analyzed. According to the BCT score, 527 (68.4%) patients were classified as low risk, and 244 (31.6%) as high risk. Meanwhile, 134 (17.4%), 516 (66.9%), and 121 (15.7%) patients were categorized into the low-, intermediate-, and high-risk groups, respectively, according to the RS ranges used in the TAILORx. The BCT high-risk group was significantly associated with advanced lymph node status, whereas no association between RS risk groups and nodal status was observed. The concordance between the two risk stratification methods in the overall population was 71.9% when the RS low-risk, and intermediate-risk groups were combined into one group. However, poor concordance was observed in patients aged ≤50 years and in those with lymph node-positive breast cancer.

Conclusions: The concordance between the BCT score and RS was low in women aged ≤50 years or with lymph node-positive breast cancer. Further studies are necessary to identify more accurate tests for predicting prognosis and chemotherapy benefit in this subpopulation.

Novel Germline Mutations of BRCA1 and BRCA2 in Korean Familial Breast Cancer Patients

Breast cancer is the second most common cancer in Korean women. Germline mutations in the BRCA1 and BRCA2 genes cause hereditary breast cancer and are detected in 15–20% of hereditary breast cancer. We investigated the BRCA1 and BRCA2 mutations in 114 familial breast cancer patients using next-generation sequencing. We confirmed 20 different mutations of BRCA1 and BRCA2 in 25 subjects (21.9%). Two such mutations in eight patients were novel (not reported in any variant database or previous study). Six mutations have been reported as disease-causing mutations in public databases. Seven mutations were found only in a single nucleotide polymorphism database and one mutation has been reported in Korea. The BRCA1/2 mutation frequency was similar to that of other studies on familial breast cancer patients in the Korean population. Further studies should examine more cases and mutations of whole exons.

Five-Year Overall Survival of Interval Breast Cancers is Better than Non- Interval Cancers from Korean Breast Cancer Registry

Objective: Interval breast cancer (IC) is a limitation of breast cancer screening. We investigated data from a large scaled breast cancer dataset of patients with breast cancer who underwent breast cancer screening in order to recapitulate the overall survival (OS) of patients with ICs compared to those with non-ICs. Methods: A total of 27,141 patients in the Korean breast cancer registry with breast cancer who had ever participated in biannual national breast cancer screening programs between 2009 and 2013 were enrolled. We compared the social, pregnancy-associated, and pathologic characteristics between the IC and non-IC groups and identified the significant prognostic factors for OS. Results: The proportion of ICs was 1.3% (370/27,141) in this study population. ICs were correlated with age 45-55 years at diagnosis, higher levels of education, early menopause (<50 years), hormone replacement therapy, specific provinces (Kangwon, Kyungnam, Jeju, and Dae-jeon), and family history of breast cancer. Low-to-intermediate nuclear grade, early stage (stage 0-I), and low Ki-67 level were also correlated with IC proportion. Non-ICs were associated with an increased risk of five-year mortality (hazard ratio [HR] 7.4; 95% confidence interval [CI]:1.85-29.66; p = 0.005) compared to ICs. Lymph node metastasis, residence (Kyung-nam province), low education status, high histologic grade, and asymptomatic cancers increased the HR of five-year OS. Conclusion: ICs occurred unequally in specific province and relatively high-educated women in Korea. They were also diagnosed with early-stage breast cancer with a favorable recurrence risk, and their outcome was better than those of patients with other breast cancers in breast cancer screening.

Prognostic role of body mass index is different according to menopausal status and tumor subtype in breast cancer patients

PURPOSE

Although controversial, obesity and underweight may have a negative impact on breast cancer outcome. However, the relationship between body mass index (BMI) and breast cancer outcomes according to tumor subtype and menopausal status remains unclear.

METHODS

This study investigated the association between BMI and breast cancer outcome in stage I-III breast cancer patients. The relationships were further evaluated according to tumor subtype and menopausal status.

RESULTS

A total of 5919 patients, 3475 (58.7%) hormone receptor (HR)(+) human epidermal growth factor receptor 2 (HER2)(-), 608 (10.3%) HR(+)HER2(+), 621 (10.5%) HR(-)HER2(+), and 1079 (18.2%) HR(-)HER2(-) were included. Underweight and obesity had a negative impact on relapse-free survival but did not affect overall survival. Importantly, the prognostic role of BMI was different according to tumor subtype and menopausal status. In HR(+)HER2(-) patients, underweight was associated with poor relapse-free survival and overall survival in pre-menopausal women. In contrast, obesity had negative impact on relapse-free survival and overall survival in HR(+)HER2(-) post-menopausal patients. Underweight may have a negative prognostic role in HR(+)HER2(+) patients. However, BMI did not impact the outcome of HR(-)HER2(+) and HR(-)HER2(-) patients.

CONCLUSIONS

The impact of BMI on breast cancer outcome was dependent on tumor subtype and menopausal status. In HR(+)HER2(-) patients, underweight and obesity had a negative prognostic role in pre-menopausal and post-menopausal women, respectively. These findings in Asian population should be further evaluated and compared in Western population.

miR-106b-5p and miR-17-5p could predict recurrence and progression in breast ductal carcinoma in situ based on the transforming growth factor-beta pathway

PURPOSE

Ductal carcinoma in situ (DCIS) is well-known precursor of invasive ductal carcinoma (IDC). Parts of patients show recurrence as DCIS or IDC after local treatment, but there are no established markers predicting relapse. We analyzed changes in miRNA and oncogene expression during DCIS progression/evolution to identify potential markers predicting recurrence.

METHODS

Forty archival tissues diagnosed as primary or recurrent DCIS and DCIS adjacent to IDC were analyzed. MiRNA hierarchical clustering showed up-regulation of miR-17-5p and miR-106b-5p in recurrent DCIS and DCIS adjacent to IDC. Target genes were predicted based on pre-formed miRNA databases and PanCancer Pathway panel. MiRNAs were transfected into MCF-10A and MCF-7 cells; western blot analysis was performed with MCF-7 cell line to evaluate the effects on TGF-β downstream pathway.

RESULTS

miRNA hierarchical clustering showed 17 dysregulated miRNAs, including miR-17-5p and miR-106b-5p. Based on miRNA database and nCounter Pancancer pathway analysis, TGFβRII was selected as target of miR-106b-5p and miR-17-5p. MiR-106b-5p- and miR-17-5p-transfected MCF-7 cells showed decreased expression of TGFβRII, especially in cells transfected with both miRNAs.

CONCLUSION

miR-106b-5p and miR-17-5p might have a role in breast cancer recurrence and progression by suppressing TGF-β activity, leading to early breast cancer carcinogenesis.

Parity Differently Affects the Breast Cancer Specific Survival from Ductal Carcinoma In Situ to Invasive Cancer: A Registry-Based Retrospective Study from Korea

Purpose:

Multiparity might increase general mortality for women, but has inconclusive in patients with breast cancer. Here, we aim to discover their effect in terms of the breast cancer development hypothesis: from ductal carcinoma in situ to invasive carcinoma.

Methods:

We included 37 947 patients from the web-based breast cancer registration program of the Korean Breast Cancer Society and analyzed survivals using multivariate Cox regression analysis and whether the associations of these factors displayed linear trends. They were divided into the following groups: (1) pure ductal carcinoma in situ (DCIS), (2) invasive ductal carcinoma (IDC) mixed with intraductal component (DCIS-IDC), and (3) node negative pure IDC.

Results:

The mean age was 48.9 ± 9.9 years including premenopausal women was 61.8%. Although patients with parities of 1-3 had better prognosis compared with patients with nulliparous women, high parity (⩾4) increased the hazard ratio (HR) of overall survival (OS) (DCIS: HR, 1.52; 95% confidence interval [CI] 0.62-3.78; IDC: HR, 1.43, 95% CI 0.89-2.31; and DCIS-IDC: HR, 1.44, 95% CI 0.45-4.59) during 84.2 (±10.7) months. For breast cancer specific survival (BCSS), the HR of the IDC group (P-value for trend = .04) increased along with increasing parity and was worse than nulliparous patients, and the HR of the DCIS-IDC group increased but was better than nulliparous patients (P-value for trend = .02). Compared with nulliparous patients, any age at first birth (AFB) decreased HR of OS in the DCIS and IDC groups (DCIS: P = .01; IDC: P = .04).

Conclusions:

Parity show dual effects on OS of women with all ductal typed breast cancer but show different effects on BCSS in Korea.

Immediate Breast Reconstruction Does Not Have a Clinically Significant Impact on Adjuvant Treatment Delay and Subsequent Survival Outcomes

Purpose

The use of immediate breast reconstruction (IBR) has been debated because it may be a causative factor in adjuvant treatment delay and may subsequently increase the probability of recurrence. We investigated whether IBR was related to adjuvant treatment delay and survival outcomes.

Methods

We retrospectively analyzed the duration from operation to adjuvant treatment administration and survival outcomes according to IBR status among patients with breast cancer who underwent mastectomy followed by adjuvant chemotherapy from January 2005 to December 2014. Propensity score matching was performed to balance the clinicopathologic baseline characteristics between patients who did and did not undergo IBR.

Results

Of 646 patients, 107 (16.6%) underwent IBR, and the median follow-up was 72 months. The median duration from surgery to adjuvant chemotherapy was significantly longer in patients who underwent IBR than in those who did not (14 vs. 12 days, respectively, p = 0.008). Based on propensity score matching, patients who underwent IBR received adjuvant therapy 3 days later than those who did not (14 vs. 11 days, respectively, p = 0.044). The duration from surgery to post-mastectomy radiation therapy (PMRT) did not significantly differ between the 2 groups. Local recurrence-free survival, regional recurrence-free survival, systemic recurrence-free survival, and overall survival were also not significantly different between the 2 groups (p = 0.427, p = 0.445, p = 0.269, and p = 0.250, respectively). In the case-matched cohort, survival outcomes did not change.

Conclusion

IBR was associated with a modest increase in the duration from surgery to chemotherapy that was statistically but not clinically significant. Moreover, IBR had no influence on PMRT delay or survival outcomes, suggesting that it is an acceptable option for patients with non-metastatic breast cancer undergoing mastectomy.

Neoadjuvant Chemotherapy and Prognosis of Pregnancy-Associated Breast Cancer: A Time-Trends Study of the Korean Breast Cancer Registry Database

Purpose

Pregnancy-associated breast cancer (PABC) is rare, and its cause and prognosis are not well known. Additionally, treatment is limited with respect to the risk to the fetus. The purpose of this study was to investigate the characteristics and treatment trends of PABC and the survival rate according to the treatment.

Methods

In the Korean Breast Cancer Society Registry database, women younger than 50 years and who were diagnosed with breast cancer from 1996 to 2015 were included. PABC was defined as breast cancer diagnosed during pregnancy or within 1 year after delivery.

Results

We examined 411 patients with PABC and 83,381 patients with non-PABC. Over time, the proportions of patients undergoing breast-conserving surgery and sentinel lymph node biopsy increased, and neoadjuvant chemotherapy and radiation therapy administration rates also increased. In the past, the overall survival of patients with PABC was poorer than that of patients with non-PABC, but there was no difference in overall survival rates in more recent years. There was no difference in overall survival rates between patients who received neoadjuvant chemotherapy (hazard ratio [HR], 1.28; 95% confidence interval [CI], 0.66–2.49; p=0.459), but PABC conferred poorer prognosis than non-PABC in patients receiving adjuvant chemotherapy (HR, 1.63; 95% CI, 1.27–2.08; p<0.001).

Conclusion

There was no difference in the prognosis between patients with PABC and those with non-PABC receiving neoadjuvant chemotherapy. The increase in neoadjuvant chemotherapy according to current treatment guidelines is expected to improve the survival rate of patients with PABC.

Questionnaire study of the dietary habits of breast cancer survivors and their relationship to quality of life (KROG 14-09)

We evaluated the dietary habits of breast cancer survivors and investigated the relationship with quality of life (QoL), with 1,156 survivors recruited from 17 institutions. We used the Questionnaire Survey of Dietary Habits of Korean Adults (Q-DH-KOR) comprising 25 questions. The following indices were derived as follows: (1) quality of healthy dietary habits (Q-HD)-eight questions on number of meals, regularity, quantity, duration, skipping breakfast, dinner with companion(s), overeating and late-night snacks; (2) habits of nutritional balance (H-NB)-questions on consuming five food categories (grains, fruits, proteins, vegetables and dairy products); and (3) habits of unhealthy foods (H-UF)-questions on consuming three food categories (fatty, instant and fast foods). The times and regularity of meals, frequency of skipping breakfast, dinner with companion(s) and overeating were better in groups with high symptomatic and functional QoL. Symptomatic QoL positively affected Q-HD and H-NB (p < 0.001 and p = 0.024 respectively) and negatively affected H-UF (p = 0.02). Breast cancer survivors more frequently ate from the fruit, protein and vegetable categories than did the control group, with lower H-UF and higher Q-HD values (p < 0.001 and p < 0.001 respectively). Our findings supported the relationship between QoL and dietary habit and showed healthier dietary habits of breast cancer survivors than controls.

Cancer risk after renal transplantation in South Korea: a nationwide population-based study

Background

This study aimed to evaluate patterns of posttransplant malignancies among renal transplant recipients (RTRs) in South Korea using nationwide data.

Methods

The nationwide cohort assessed in this study included RTRs from January 1, 2010, to December 31, 2014. We analyzed cancer incidence during the time course after renal transplantation. Additionally, we calculated standardized incidence ratios (SIRs) to evaluate the risk of malignancies in RTRs.

Results

A total of 1343 RTRs (871 males and 472 females, mean age 48.5 ± 11.6 years) were assessed. Among them, 104 (7.7%) developed malignancies after transplantation, most commonly in the thyroid cancer (23.1%). The SIR for all cancers was 3.54; particularly, the SIRs for renal cancer, myeloma, and non-Hodgkin lymphoma were 16.31, 24.02, and 28.64, respectively. Females showed a higher risk of malignancy than males (SIRs: 4.04 for women and 3.26 for men). The median interval between transplantation and malignancy diagnosis was 27.2 months (range 12.3–54.8 months).

Conclusions

RTRs in South Korea demonstrated a high risk of malignancy after transplantation compared with the general population. This indicates that close surveillance and routine screening for cancer in RTRs are needed.

Clinical implication of subcategorizing T2 category into T2a and T2b in TNM staging of breast cancer

Regarding TNM staging in breast cancer, T2 category is currently not divided into subcategories even though it covers a wider range of tumor sizes than T1 category. Using Korean Breast Cancer Registry database, data of 41 071 women diagnosed as non-metastatic T2 breast cancer between 2001 and 2014 were analyzed. Cutoff value for optimal tumor size was approximated by receiver operating characteristic (ROC) curve to subcategorize T2 tumors. Overall survival (OS) was compared between two subcategories. Median follow-up period was 65 months. Of 41 071 patients, 4504 (11.0%) died. Based on ROC curve analysis, 3.0 cm was selected as the cutoff value. Five-year OS rate was 91% in patients with breast tumors ≤3.0 cm (T2a) and 86% in patients with breast tumors >3.0 cm (T2b) (log-rank P < 0.001). T2b subcategory showed worse OS than T2a subcategory regardless of node status (log-rank P < 0.001 for all node categories). Within every subgroup defined by primary OS analysis covariates, T2b subcategory consistently showed worse outcome compared to T2a subcategory. By multivariate analysis, T2b subcategory was a significant independent prognostic factor of OS (hazard ratio: 1.26, 95% CI = 1.18-1.34). T2 category of breast cancer could be subcategorized into T2a and T2b with a cutoff value of 3 cm. These subcategories definitely showed different OSs even after adjusted for known prognostic factors. Subcategorization of T2 category might be useful for predicting prognosis more accurately and tailoring adjuvant therapy.

The Shiraz Breast Cancer Registry (SBCR): study design and primary reports

AIM

This is a description of the largest breast cancer (BC) registry in Iran, termed the Shiraz Breast Cancer Registry (SBCR).

METHODS

Data on baseline and clinical characteristics, socioeconomic status, imaging, physical examination, histopathology, treatment and prognosis have been recorded for each individual.

RESULTS

Overall, 5937 were included in the report. Mean age of first presentation was 49.05 ± 11.69 years. Mean tumor size was 2.78 ± 1.76 cm. Most patients had stage 2 (46.9%) and 3 (25.5%) BCs, respectively. Most common type of BC was invasive ductal carcinoma (83.3%), followed by medullary carcinoma (3.8%). Overall, 12.9% were triple negative (HER2-, ER- and PR-).

CONCLUSION

The study provides an overview on the status of BC's in Iran and a wide opportunity for future studies.

Discordance of the PAM50 Intrinsic Subtypes Compared with Immunohistochemistry-Based Surrogate in Breast Cancer Patients: Potential Implication of Genomic Alterations of Discordance

Purpose

We aimed to analyze the discordance between immunohistochemistry (IHC)-based surrogate subtyping and PAM50 intrinsic subtypes and to assess overall survival (OS) according to discordance.

Materials and Methods

A total of 607 patients were analyzed. Hormone receptor (HR) expression was evaluated by IHC, and human epidermal growth factor receptor 2 (HER2) expression was analyzed by IHC and/or fluorescence in situ hybridization. PAM50 intrinsic subtypes were determined according to 50 cancer genes using the NanoString nCounter Analysis System. We matched concordant tumor as luminal A and HR+/HER2–, luminal B and HR+/HER2+, HR–/HER2+ and HER2–enriched, and triple-negative breast cancer (TNBC) and normal- or basal-like. We used Ion Ampliseq Cancer Panel v2 was used to identify the genomic alteration related with discordance. The Kaplan-Meier method was used to estimate OS.

Results

In total, 233 patients (38.4%) were discordant between IHC-based subtype and PAM50 intrinsic subtype. Using targeted sequencing, we detected somatic mutation–related discordant breast cancer including the VHL gene in the HR+/HER2– group (31% in concordant group, 0% in discordant group, p=0.03) and the IDH and RET genes (7% vs. 12%, p=0.02 and 0% vs. 25%, p=0.02, respectively) in the TNBC group. Among the luminal A/B patients with a discordant result had significantly worse OS (median OS, 73.6 months vs. not reached; p < 0.001), and among the patients with HR positivity, the basal-like group as determined by PAM50 showed significantly inferior OS compared to other intrinsic subtypes (5-year OS rate, 92.2% vs. 75.6%; p=0.01).

Conclusion

A substantial portion of patients showed discrepancy between IHC subtype and PAM50 intrinsic subtype in our study. The survival analysis demonstrated that current IHC-based classification could mislead the treatment and result in poor outcome. Current guidelines for IHC might be updated accordingly.

The effect of adjuvant chemotherapy on survival in Korean patients with node negative T1c, triple negative breast cancer

Background

The present study investigated the prognostic role of adjuvant systemic chemotherapy in patients with node negative, T1c triple negative breast cancer (TNBC) from a nationwide cohort. In addition, the prognostic effect between 3 different chemotherapy regimens were compared in node-negative T1c TNBC patients by subgroup analysis.

Methods

From the Korean breast cancer registry database, 1,151 T1c node negative TNBC patients were included in this study. Patients were categorized into four treatment groups according to chemotherapy regimen: (1) no chemotherapy, (2) adriamycin plus cyclophosphamide (AC), (3) adriamycin/epirubicin plus cyclophosphamide plus 5-FU (FAC/FEC), and (4) cyclophosphamide plus 5-FU plus methotrexate (CMF). Overall survival (OS) was evaluated between each patient group.

Results

Of the 1,151 T1c node negative TNBC patients, 1,006 received adjuvant chemotherapy, while 145 received no chemotherapy. Among the patients receiving adjuvant chemotherapy the distribution of regimens was: 586 AC, 168 FAC/FEC (126 FAC, 42 FEC), and 252 CMF. The mean follow-up time of the full study cohort was 87.98 ± 33.56 months (range = 6–192 months). Patients in the no chemotherapy group showed significantly worse OS compared to each chemotherapy regimen group. However, when OS was compared between each chemotherapy regimen, no significant difference was found.

Conclusions

This study showed that adjuvant systemic chemotherapy improved OS in T1c node negative TNBC patients, regardless of chemotherapy between AC, FAC/FEC, and CMF regimens.

Trends in breast reconstruction: Implications for the National Health Insurance Service

Background

Breast reconstruction has become more common as mastectomy has become more frequent. In Korea, the National Health Insurance Service (NHIS) began covering breast reconstruction in April 2015. This study aimed to investigate trends in mastectomy and breast reconstruction over the past 10 years and to evaluate the impact of NHIS coverage on breast reconstruction.

Methods

Nationwide data regarding mastectomy and breast reconstruction were collected from the Korean Breast Cancer Society registry database. Multiple variables were analyzed in the records of patients who underwent breast reconstruction from January 2005 to March 2017 at a single institution.

Results

At Seoul National University Hospital, the total number of reconstruction cases increased 13-fold from 2005 to 2016. The proportion of immediate breast reconstruction (IBR) cases out of all cases of total mastectomy increased from 4% in 2005 to 52.0% in 2016. The proportion of delayed breast reconstruction (DBR) cases out of all cases of breast reconstruction and the overall number of DBR cases increased from 8.8% (20 cases) in 2012 to 18.3% (76 cases) in 2016. After NHIS coverage was initiated, the proportions of IBR and DBR showed statistically significant increases (P<0.05). Among the IBR cases, the percentage of prosthesis-based reconstructions increased significantly (P<0.05), but this trend was not found with DBR. Total mastectomy became significantly more common after the expansion of NHIS coverage (P<0.05).

Conclusions

Over the last decade, there has been an increase in mastectomy and breast reconstruction, and the pace of increase accelerated after the expansion of NHIS coverage. It is expected that breast reconstruction will be a routine option for patients with breast cancer under the NHIS.

Value of ultrasound-guided fine needle aspiration in diagnosing axillary lymph node recurrence after breast cancer surgery

BACKGROUND

This article aims to assess the diagnostic performance of ultrasound-guided fine needle aspiration (US-FNA) in diagnosing axillary lymph node (ALN) recurrence in patients with a history of breast cancer.

METHODS

From January 2005 to June 2015, 231 US-FNA examinations performed for suspicious axillary lesions in 218 patients with a history of breast cancer were included. Diagnostic performance of US-FNA for ALN recurrence were evaluated.

RESULTS

Of the 231 US-FNA examinations, 172 (74.5%) obtained negative and 59 (25.5%) obtained positive cytological results. All US-FNA-negative axillary lesions were considered imaging-cytology concordant and underwent follow-up, with one false-negative result (false negative rate, 1.6% [1/60]). The overall sensitivity, specificity, PPV and NPV of US-FNA for diagnosing ALN recurrence/metastasis per examination were 98.3% (59/60), 100% (171/171), 100% (59/59) and 99.4% (171/172). When excluding nine patients with newly developed contralateral breast cancer, the sensitivity, specificity, PPV and NPV of US-FNA for diagnosing ALN recurrence was 98.1% (51/52),100% (170/170),100% (51/51) and 99.4% (170/171).

CONCLUSIONS

US-FNA is a reliable method for diagnosing axillary recurrence in patients with a history of breast cancer.

Validating the efficacy of single-stage breast-conserving therapy using multicatheter partial-breast brachytherapy based on updated ASTRO guidelines

Based on the accumulating evidence for equivalent results of partial-breast irradiation (PBI) and whole-breast irradiation (WBI) in breast-conserving therapy (BCT), the American Society for Radiation Oncology (ASTRO) updated the consensus statement (CS) to expand the range of potential candidates for PBI outside clinical trials. Of the various techniques, PBI using multicatheter interstitial brachytherapy (MCB) is the oldest and has long-term data. In this study, the efficacy of single-stage BCT using MCB-PBI achieved by an intraoperative catheter placement was validated on updated ASTRO guidelines. We retrospectively examined patients undergoing BCT using MCB-PBI or WBI. The updated CS distinguished patients aged 40-49 years with ER+, tumor ≤2 cm, and margin ≥2 mm from unsuitable patients in the previous CS. We compared the ipsilateral breast tumor recurrence (IBTR) rate in MCB-PBI with that in WBI patients with suitable or cautionary (S/C) categories on the updated CS. Between November 2007 and September 2017, 641 patients with 647 lesions underwent BCT (MCB-PBI, 407; WBI, 240). At the median follow-up time of 54.4 months, we observed 8 (1.97%; 95% CI: 0.62-3.31%) and 7 (2.92%; 95% CI: 0.79-5.05%) IBTRs, respectively. Updating the CS increased the S/C patients receiving MCB-PBI from 232 patients (57.0%) to 319 (78.4%). Comparison of clinical outcomes at the 12-month minimum follow-up between 291 MCB-PBI and 103 WBI in S/C patients showed no significant differences in the 4-year rate of IBTR-free (100% vs 98.9%; P = 0.29) and disease-free survival (98.7% vs 95.5%; P = 0.24). Overall, single-stage BCT using MCB-PBI offered similar tumor control rates, compared with WBI, on the updated ASTRO CS.

Multi-omics profiling of younger Asian breast cancers reveals distinctive molecular signatures

Breast cancer (BC) in the Asia Pacific regions is enriched in younger patients and rapidly rising in incidence yet its molecular bases remain poorly characterized. Here we analyze the whole exomes and transcriptomes of 187 primary tumors from a Korean BC cohort (SMC) enriched in pre-menopausal patients and perform systematic comparison with a primarily Caucasian and post-menopausal BC cohort (TCGA). SMC harbors higher proportions of HER2+ and Luminal B subtypes, lower proportion of Luminal A with decreased ESR1 expression compared to TCGA. We also observe increased mutation prevalence affecting BRCA1, BRCA2, and TP53 in SMC with an enrichment of a mutation signature linked to homologous recombination repair deficiency in TNBC. Finally, virtual microdissection and multivariate analyses reveal that Korean BC status is independently associated with increased TIL and decreased TGF-β signaling expression signatures, suggesting that younger Asian BCs harbor more immune-active microenvironment than western BCs.

While breast cancer incidence in the Asia Pacific region is rising, the molecular basis remains poorly characterized. Here the authors perform genomic screening of 187 Korean breast cancer patients and find differences in molecular subtype distribution, mutation pattern and prevalence, and gene expression signature when compared to TCGA.

Basic Findings Regarding Breast Cancer in Korea in 2015: Data from a Breast Cancer Registry

The Korean Breast Cancer Society (KBCS) has established a nationwide breast cancer database using an online registration program in 1996. The present study aimed to analyze the basic findings and trends of breast cancer in Korea in 2015 using the data provided by the Korea Central Cancer Registry and the KBCS. In 2015, a total of 22,550 patients were newly diagnosed with breast cancer, of which 3,331 were carcinoma in situ cases and 19,219 were invasive cancer cases. The incidence rate of breast cancer in Korea has steadily increased since the nationwide database was established, and the crude rate and age-standardized rate including that of carcinoma in situ, were 88.1 and 66.0 cases per 100,000 women, respectively. In terms of age, the incidence of breast cancer was the highest in the 40–49-year-old age group (7,889 patients, 35.0%). With regard to surgical procedure, breast-conserving surgery was frequently performed (62.3%). However, the rate of mastectomy has been gradually increasing since 2012, that is, from 32.3% in 2014 to 36.1% in 2015. The rate of early breast cancer has continued to increase, and that of stages III and IV breast cancer was only 9.1% at the time of diagnosis. However, the 5-year survival rate of patients with carcinoma in situ from 2011 to 2015 was 92.3%, which was 14.4% higher than that from 1993 to 1995 (77.9%). Analysis of data from the nationwide registry of breast cancer will not only help to understand the characteristics of breast cancer in individuals in Korea, but will also significantly contribute to the treatment and research of breast cancer. Therefore, a high quality database for breast cancer in Korea must be established by further initiating registration project and establishing an objective legal basis.

Clinical Characteristics and Prognosis Associated with Multiple Primary Cancers in Breast Cancer Patients

Purpose

Breast cancer is one of the most common malignancies worldwide and the second most common cancer among Korean women. The prognosis of breast cancer is poor in patients with other primary cancers. However, there have been few clinical studies regarding this issue. Therefore, we analyzed the characteristics and prognosis of patients with breast cancer with multiple primary cancers (MPCs).

Methods

Data from the Korean Breast Cancer Society Registry were analyzed. Data from enrolled patients who underwent surgery for breast cancer were analyzed for differences in prognosis dependent on the presence of MPCs, and which MPC characteristics affected their prognosis.

Results

Among the 41,841 patients analyzed, 913 patients were found to have MPCs, accounting for 950 total MPCs. There was a significant difference in survival rates between the breast cancer only group and the MPC group. The 5-year survival rates were 93.6% and 86.7% and the 10-year survival rates were 87.5% and 70.4%, respectively. Among the 913 patients with MPCs, patients with two or more MPCs had significantly worse prognoses than patients with a single MPC. With respect to the time interval between breast cancer and MPC occurrence, patients with a 5-year or greater interval had significantly better prognoses than patients with less than 1 year between occurrences. Among MPCs, thyroid cancer was the most common primary cancer. However, this type was not related to the prognosis of breast cancer. Gynecologic cancer, colorectal cancer, upper gastrointestinal cancer, and lung cancer were related to breast cancer prognosis.

Conclusion

MPCs were a poor prognostic factor for patients with breast cancer. Two or more MPCs and a shorter time interval between occurrences were worse prognostic factors. Although MPCs were a poor prognostic factor, thyroid cancer did not affect the prognosis of patients with breast cancer.

Chronological Improvement in Survival of Patients with Breast Cancer: A Large-Scale, Single-Center Study

Purpose

This study aimed to chronologically evaluate survival of patients with breast cancer in Korea and investigate the observed changes during the last 20 years. We also sought to determine factors that may influence outcomes and changes in the duration of survival over time.

Methods

We retrospectively analyzed a total of 10,988 patients with breast cancer who were treated at our institution between January 1993 and December 2008. We divided the study period into three periods (P1, 1993–1997; P2, 1998–2002; and P3, 2003–2008). We retrospectively reviewed the collected data from the Asan database, including age at diagnosis, clinical manifestations, pathology report, surgical methods, types of adjuvant treatment modalities, type of recurrence, and follow-up period.

Results

At a median follow-up of 8.2 years, we observed that survival outcomes have improved recently. The 5-year breast cancer-specific survival (BCSS) rate also increased from 82.8% in P1 to 92.6% in P3 (p<0.001). The survival rate in patients with tumors at each stage increased in similar patterns in all patients, and, remarkably, there was a significant survival improvement in patients with stage III breast cancer (P1 vs. P3: 5-year BCSS, 57.4% vs. 80.0%, p<0.001). The time period was a significant prognostic factor in multivariate analysis (P1 vs. P2: hazard ratio [HR], 0.83, p=0.035; P1 vs. P3: HR, 0.75, p=0.015).

Conclusion

The study results suggest an improvement in breast cancer survival in Korea, which is consistent with the development of treatments and early detection.

The usefulness of fluorodeoxyglucose-PET/CT for preoperative evaluation of ductal carcinoma in situ

Purpose

PET/CT is useful in preoperative evaluation of invasive breast cancer (IBC) to predict axillary metastasis and staging workup. The usefulness is unclear in cases of ductal carcinoma in situ (DCIS) diagnosed at biopsy before surgery, which sometimes is upgraded to IBC after definitive surgery. The aim of this study is to find out the usefulness of PET/CT on DCIS as a preoperative evaluation tool.

Methods

We investigated 102 patients preoperatively diagnosed with DCIS who subsequently underwent definitive surgery between 2010 and 2015. The uptake of ¹⁸F-fluorodeoxyglucose was graded by visual and semiquantitative methods. We analyzed the maximum standardized uptake value (SUVmax) of each patient with clinicopathologic variables. We determined optimal cutoff values for SUVmax by receiver operating characteristic curve analysis.

Results

Fifteen cases out of 102 cases (14.7%) were upgraded to IBC after surgery. The SUVmax was higher in patients upgraded to IBC (mean: 2.56 vs. 1.36) (P = 0.007). The SUVmax was significantly higher in patients who had symptoms, palpable masses, lesions over 2 cm in size and BI-RAD category 5. Both visual and semiquantitative analysis were significant predictors of IBC underestimation. SUVmax of 2.65 was the theoretical cutoff value in ROC curve analysis in predicting the underestimation of IBC. The underestimation rate was significantly higher in patients with SUVmax >2.65 (P < 0.001), over the moderate enhanced uptake on visual analysis (P < 0.001).

Conclusion

PET/CT can be used as a complementary evaluation tool to predict the underestimation of DCIS combined with the lesion size, palpable mass, symptomatic lesion, and BI-RAD category.

Fertility preservation for patients with breast cancer: The Korean Society for Fertility Preservation clinical guidelines

With advances in the methods of cancer treatment used in modern medicine, the number of breast cancer survivors has been consistently rising. As the number of women who wish to become pregnant after being diagnosed with breast cancer increases, it is necessary to consider fertility preservation in these patients. However, medical doctors may be unaware of the importance of fertility preservation among cancer patients because most patients do not share their concerns about fertility with their doctors. Considering the time spent choosing and undergoing treatment, an early referral to a reproductive specialist is the best way to prevent a delay in cancer treatment. Since it is not easy to make decisions on matters related to cancer diagnosis and fertility, patients should be provided with enough time for decision-making, and to allow for this, an early referral will provide patients with sufficient time to choose an appropriate method of fertility preservation. The currently available options of fertility preservation for patients with breast cancer include cryopreservation of embryos, oocytes, and ovarian tissue and gonadotropin-releasing hormone agonist treatment before and during chemotherapy. An appropriate method of fertility preservation must be selected through consultations between individual patients and health professionals and analyses of the pros and cons of different options.

Selective Radiation Therapy for Ductal Carcinoma In Situ Following Breast-Conserving Surgery According to Age and Margin Width: Korean Radiation Oncology Group 11-04 and 16-02 Studies

Purpose

The optimal indications for omitting adjuvant radiation therapy (RT) after breast-conserving surgery are still controversial in ductal carcinoma in situ (DCIS) of the breast. The purpose of this study was to validate the role of postoperative RT in DCIS patients aged ≤50 years and with tumor margin widths of <1 cm, both of which have been proven to be high-risk features for recurrence in cohorts not receiving RT.

Methods

Using two multicenter retrospective studies on DCIS, a pooled analysis was performed among patients aged ≤50 years and with margin widths <1 cm. All patients underwent breast-conserving surgery. Two hundred thirty-two patients received postoperative RT, while 54 did not. The median follow-up period was 77 months (range, 2-190 months) and 70 months (range, 5-166 months) in the patients who received RT and those who did not, respectively.

Results

The patients who received RT had larger tumors (p<0.001), higher nuclear grade (p<0.001), closer margin width (p<0.001), and negative estrogen receptor expression (p=0.010) compared with those who did not receive RT. During the follow-up period, there were 17 ipsilateral breast tumor recurrences (IBTRs) as follows: invasive carcinoma in 10 patients and DCIS in seven. In the univariate analysis, the treatment with RT and human epidermal growth factor receptor 2 (HER2) status were significant risk factors for IBTR. The 7-year IBTR rates with and without postoperative RT were 3.6% and 13.1%, respectively (p=0.008). HER2-positive tumors had a higher IBTR rate than the HER2-negative tumors (7-year rate, 13.6% vs. 3.9%; p=0.003).

Conclusion

Postoperative RT following breast-conserving surgery significantly reduced the 7-year IBTR rate in the DCIS patients aged ≤50 years and with margin widths <1 cm. HER2 positivity was associated with increased IBTR in these patients.

Predictive and prognostic value of sphingosine kinase 1 expression in patients with invasive ductal carcinoma of the breast

Sphingosine kinase 1 (SPHK1) has been found to be upregulated in many different types of human malignancy and plays a crucial role in cancer development and progression. However, the potential of SPHK1 to act as a predictive and prognostic biomarker in breast cancer remains to be clarified. In the present study, SPHK1 expression was evaluated in breast cancer cell lines and 224 breast cancer tissue samples using immunohistochemical staining. Compared to the normal mammary epithelial cell line MCF-10A, SPHK1 mRNA and protein expression levels increased in the breast cancer cell lines SK-BR-3, MDA-MB-231, MDA-MB-436, and MCF-7. Immunohistochemical staining revealed SPHK1 expression to be significantly increased in breast cancer tissue compared to normal breast tissue, with 85 (37.9%) of the 224 invasive ductal carcinomas (IDC) exhibiting high SPHK1 expression. High SPHK1 expression in IDC showed a significant association with higher histological grade, distant metastasis, and triple negativity, and was shown to be an independent predictor for distant metastasis development. In addition, patients with high SPHK1 expression had significantly lower progression-free survival and overall survival rates compared to those with low SPHK1 expression. Our data suggest that SPHK1 is involved in the development and progression of breast cancer and can serve as a potential predictive biomarker of distant metastasis and patient outcome.

Comparison of the association of mammographic density and clinical factors with ductal carcinoma in situ versus invasive ductal breast cancer in Korean women

BACKGROUND

In spite of the increasing incidence of in situ breast cancer, the information about the risk factors of in situ breast cancer (DCIS) is scarce as compared to the information available for invasive ductal breast cancer (IDC), with inconsistent findings regarding the difference in risk factors between DCIS and IDC.

METHODS

We enrolled 472 women with IDC and 90 women with DCIS and 1088 controls matching for age and menopausal status. Information on risk factors was collected through self-administered questionnaire. Percent mammographic dense area (PDA), absolute mammographic dense area (ADA), and nondense area were assessed using a computer-assisted thresholding technique. Odds ratio (OR) and 95% confidence intervals (CI) were estimated by conditional logistic regression model with adjustment for covariates.

RESULTS

Later age at menarche and regular physical exercise were associated with decreased risk of IDC, whereas alcohol consumption, previous benign breast disease, and family history of breast cancer were associated with increased risk of IDC. For DCIS, previous benign breast disease and alcohol consumption were associated with the increased risk, and regular physical exercise was associated with decreased risk. Increase of ADA by 1-quartile level and PDA increase by 10% were associated with 1.10 (95% CI: 1.01, 1.21) and 1.10 (95% CI: 1.01, 1.19) times greater risk of IDC, respectively. The increase of ADA by 1-quartile level and PDA increase by 10% were associated with 1.17 (95% CI: 0.91, 1.50) times and 1.11 (95% CI:0.90,1.37) times greater risk of DCIS, respectively, but the associations were not statistically significant. There was no significant difference in the association with risk factors and mammographic density measures between IDC and DCIS (P > 0.1).

CONCLUSIONS

Differential associations of DCIS with mammographic density and risk factors as compared with the associations of IDC were not evident. This finding suggests that IDC and DCIS develop through the shared causal pathways.

Comparison of outcomes of surgeon-performed intraoperative ultrasonography-guided wire localization and preoperative wire localization in nonpalpable breast cancer patients undergoing breast-conserving surgery: A retrospective cohort study

This study aimed to determine the efficacy of intraoperative ultrasonography-guided wire localization guided breast-conserving surgery (BCS) for nonpalpable breast cancer and compare it to conventional preoperative wire localization (PWL) guided surgery.We retrospectively analyzed the medical charts of 214 consecutive nonpalpable breast cancer patients who underwent BCS using intraoperative ultrasonography-guided wire localization by a surgeon (IUWLS) and PWL, between April 2013 and March 2017. Positive surgical margins, reexcision rates, and resection volumes were investigated.Of the total cohort, 124 patients underwent BCS with IUWLS and 90 patients with PWL. The following did not differ between the IUWLS and PWL groups: positive margin status, re-excision rate, conversion rate, permanent positive margin status, reoperation rate, median optimal resection volume (ORV), median total resection volume (TRV), and median closest tumor-free margin. Rather, median (range) widest tumor-free margin was significantly smaller in the IUWLS group (9 mm [5-12]) than in the PWL group (14 mm [9-20]; P = .003]). Median (range) calculated resection ratio (CRR) was significantly lower in the IUWLS group (1.67 [0.87-9.38]) than in the PWL group (4.83 [1.63-21.04]; P = .02).In nonpalpable breast cancer patients undergoing BCS, IUWLS showed positive resection margins and reexcision rates equivalent to those of the conventional PWL method. Additionally, excision volume and widest tumor-free margin were smaller with IUWLS, confirming that healthy breast tissue is less likely to be resected with this method. Our results suggest that IUWLS offers an excellent alternative to PWL, while avoiding PWL-induced patient discomfort.

Meeting Highlights: The Second Consensus Conference for Breast Cancer Treatment in Korea

The Korean clinical practice guideline recently developed by the Korean Breast Cancer Society to address the national clinical situation is currently under revision ahead of a seventh recommendation. A second consensus conference was held to further develop this guideline by soliciting opinions regarding important issues related to surgery, radiotherapy, and medical oncology. Several issues were discussed, and the discussion progressed to pros and cons in the context of cases in various clinical situations. The panels discussed and voted on issues regarding surgical treatment for non-axillary regional lymph nodes, regional nodal irradiation of pN1 disease, and ovarian functional suppression (OFS) as an adjuvant treatment in premenopausal patients with hormone receptor-positive breast cancer. Regarding the surgical treatment of non-axillary regional lymph node, most panelists agreed with the recommendation of preoperative chemotherapy and postoperative radiotherapy for patients with biopsy-diagnosed metastases, whereas surgery or radiotherapy of non-axillary regional lymph nodes was suggested for clinical partial responders. Discussions on radiotherapy addressed the need for adjuvant radiotherapy and radiation field of regional lymph node in the context of various N1 breast cancer cases. The participants reached a consensus to recommend that N1 patients should receive regional nodal irradiation for a large tumor burden (e.g., three positive nodes, perinodal extension, or large primary tumor). Finally, the panels favored OFS in addition to endocrine therapy for premenopausal women with high risk factors such as a large tumor size, involvement of more than three nodes, and a high histologic grade.

Identifying long-term survivors among metastatic breast cancer patients undergoing primary tumor surgery

PURPOSE

The prognostic role of primary tumor surgery in women with metastatic breast cancer at diagnosis is contentious. A subset of patients who will benefit from aggressive local treatment is needed to be identified. Using a nationwide database, we developed and validated a predictive model to identify long-term survivors among patients who had undergone primary tumor surgery.

METHODS

A total of 150,043 patients were enrolled in the Korean Breast Cancer Registry between January 1990 and December 2014. Of these, 2332 (1.6%) presented with distant metastasis at diagnosis. Using Cox proportional hazards regression, we developed and validated a model that predicts survival in patients who undergo primary tumor surgery, based on the clinicopathological features of the primary tumor.

RESULTS

A total of 2232 metastatic breast cancer patients were reviewed. Of these, 1541 (69.0%) patients had undergone primary tumor surgery. The 3-year survival rate was 62.6% in this subgroup. Among these patients, advanced T-stage, high-grade tumor, lymphovascular invasion, negative estrogen receptor status, high Ki-67 expression, and abnormal CA 15-3 and alkaline phosphatase levels were associated with poor survival. A prediction model was developed based on these factors, which successfully identified patients with remarkable survival (score 0-3, 3-year survival rate 87.3%). The clinical significance of the model was also validated with an independent dataset.

CONCLUSIONS

We have developed a predictive model to identify long-term survivors among women who undergo primary tumor surgery. This model will provide guidance to patients and physicians when considering surgery as a treatment modality for metastatic breast cancer.

Care Pathway for Cancer Survivorship in Korea: Trend of Breast Cancer Pathway from 2003 to 2010

Objectives

The survival rate of cancer patients has exceeded 60%. Although cancer survivors may die of other diseases except cancer, the health management system including chronic disease prevention-management for cancer survivors, has not been established in the diverse aspects. Therefore, services according to care pathway of cancer patients need to be provided through a support system based on a platform concept that can be used to meet patient needs in various ways.

Methods

A sample cohort database (2002–2010) of approximately 1 million persons—2% of the whole nation (50 million)—was used to estimate cancer survivors through a principal care pathway for cancer management. The sample cohort database was built to estimate the number of breast cancer survivors in the five stage: ‘Diagnosis and treatment,’ ‘Supportive care,’ ‘Monitoring,’ ‘Progress illness,’ and ‘Hospice care’. In this way, the scale of breast cancer survivors was estimated.

Results

There were 330 (9.8%) cases of the incidence of cancer in 2010 in the ‘Diagnosis and treatment.’ Among the cases of the incidence of cancer in the previous year, the number of one-year survivors was 328 (9.7%); these were included in the category ‘Supportive care.’ In the ‘Monitoring’ category, 2,593 (76.9%) who maintained health lives were included. A total of 84 (2.5%) survivors were checked to identify an ongoing disease; these were included in the category ‘Progress illness.’ In the category ‘Hospice care,’ 36 (1.1%) end-stage cancer patients requiring hospice care were included.

Conclusions

We established a care pathway by survival stage in order to fulfill prevention and health management services post-treatment management steps.

Basic Facts of Breast Cancer in Korea in 2014: The 10-Year Overall Survival Progress

We, the Korean Breast Cancer Society (KBCS), present the facts and the trends of breast cancer in Korea in 2014. Data on the total number of newly diagnosed patients was obtained from the Korea Central Cancer Registry database, other data were collected from the KBCS online registry database, and the overall survival data of patients were updated from Statistics Korea. A total of 21,484 female patients were newly diagnosed with breast cancer in 2014. The crude incidence rate and the age-standardized incidence rate (ASR) of breast cancer in female patients, including carcinoma in situ, were 83.4 cases and 63.9 cases per 100,000 women, respectively. The ASR showed an annual increase of 6.1% from 1999 to 2014; however, although the increase of the ASR had slowed since 2008, the incidence rate itself continuously increased. The proportion of early breast cancer increased consistently, and the pathological features changed accordingly. While breast-conserving surgery was mainly performed, the proportion of total mastectomy was slightly increased. The total number of breast reconstruction surgeries increased rapidly. The 5-year and 10-year overall survival rates for all stages of breast cancer patients were 91.2% and 84.8%, respectively. The overall survival rate of Korean patients with breast cancer was extremely high, compared with other developed countries. Thus, we consider that the clinical characteristics of breast cancer have changed over the past decade. A nationwide registry data will contribute to a better understanding of the characteristics of breast cancer in Korea.

Oncologic Outcomes after Immediate Breast Reconstruction Following Total Mastectomy in Patients with Breast Cancer: A Matched Case-Control Study

Purpose

The use of immediate breast reconstruction (IBR) following total mastectomy (TM) has increased markedly in patients with breast cancer. As the indications for IBR have been broadened and more breast-conserving surgery-eligible patients are undergoing IBR, comparing the oncologic safety between TM only and IBR following TM becomes more difficult. This study aimed to analyze the oncologic outcomes between TM only and IBR following TM via a matched case-control methodology.

Methods

A retrospective review was conducted to identify all patients who underwent TM between 2008 and 2014. We excluded patients who underwent neoadjuvant chemotherapy, including palliative chemotherapy, and had a follow-up duration <12 months, inflammatory breast cancer, or incomplete data. We divided the remaining patients into two groups: those who underwent TM only (control group) and those who underwent IBR following TM (study group). The groups were propensity score-matched. Matched variables included age, pathologic stage, estrogen or progesterone receptor status, human epidermal growth factor receptor 2 status, and year of operation.

Results

After matching, 878 patients were enrolled in the control group and 580 patients in the study group. The median follow-up duration was 43.4 months (range, 11–100 months) for the control group and 41.3 months (range, 12–100 months) for the study group (p=1.000). The mean age was 47.3±8.46 years for the control group and 43.9±7.14 years for the study group (p>0.050). Matching was considered successful for the matching variables and other factors, such as family history, histology, multiplicity, and lymphovascular invasion. There were no significant differences in overall survival (log-rank p=0.454), disease-free survival (log-rank p=0.186), local recurrence-free survival (log-rank p=0.114), or distant metastasis-free survival rates (logrank p=0.537) between the two groups.

Conclusion

Our results suggest that IBR following TM is a feasible treatment option for patients with breast cancer.

Clinicopathologic and Prognostic Significance of Transducin-Like Enhancer of Split 1 Protein Expression in Invasive Breast Cancer

Purpose

Transducin-like enhancer of split 1 (TLE1) is a member of the TLE family of transcriptional co-repressors that control the transcription of a wide range of genes. We investigated the prognostic significance of TLE1 protein expression in breast cancers by using immunohistochemistry and explored the relationship of TLE1 with clinicopathological parameters.

Methods

Immunohistochemistry was performed on 456 cases of breast cancer tiled on tissue microarrays. The relationship between TLE1 expression in normal breast specimens and ductal carcinoma in situ (DCIS) was also analyzed.

Results

TLE1 was highly expressed in 57 of 456 (12.5%) carcinoma samples. TLE1 was more frequently expressed in DCIS and invasive breast cancers than in normal breast tissue (p=0.002). High expression of TLE1 significantly correlated with negative lymph node (LN) metastasis (p=0.007), high histologic grade (p<0.001), estrogen receptor negativity (p<0.001), progesterone receptor negativity (p<0.001), human epidermal growth factor receptor 2 (HER2) positivity (p<0.001), and high Ki-67 proliferation index (p<0.001). Based on intrinsic subtypes, high TLE1 expression was strongly associated with HER2+ and triple-negative breast cancers (TNBC) (p<0.001). Survival analysis demonstrated no significant association between TLE1 expression and disease-free survival (DFS) (p=0.167) or overall survival (OS) (p=0.286). In subgroup analyses, no correlation was found between TLE1 expression and DFS or OS according to LN status or intrinsic subtype.

Conclusion

High TLE1 expression is significantly associated with the HER2+ and TNBC subtypes. This is the first study documenting immunohistochemical expression of TLE1 in invasive breast cancer and its association with clinicopathological parameters, prognosis, and intrinsic subtype.

Education Level Is a Strong Prognosticator in the Subgroup Aged More Than 50 Years Regardless of the Molecular Subtype of Breast Cancer: A Study Based on the Nationwide Korean Breast Cancer Registry Database

Purpose

This study investigated the role of the education level (EL) as a prognostic factor for breast cancer and analyzed the relationship between the EL and various confounding factors.

Materials and Methods

The data for 64,129 primary breast cancer patients from the Korean Breast Cancer Registry were analyzed. The EL was classified into two groups according to the education period; the high EL group (≥ 12 years) and low EL group (< 12 years). Survival analyses were performed with respect to the overall survival between the two groups.

Results

A high EL conferred a superior prognosis compared to a low EL in the subgroup aged > 50 years (hazard ratio, 0.626; 95% confidence interval [CI], 0.577 to 0.678) but not in the subgroup aged ≤ 50 years (hazard ratio, 0.941; 95% CI, 0.865 to 1.024). The EL was a significant independent factor in the subgroup aged > 50 years according to multivariate analyses. The high EL group showed more favorable clinicopathologic features and a higher proportion of patients in this group received lumpectomy, radiation therapy, and endocrine therapy. In the high EL group, a higher proportion of patients received chemotherapy in the subgroups with unfavorable clinicopathologic features. The EL was a significant prognosticator across all molecular subtypes of breast cancer.

Conclusion

The EL is a strong independent prognostic factor for breast cancer in the subgroup aged > 50 years regardless of the molecular subtype, but not in the subgroup aged ≤ 50 years. Favorable clinicopathologic features and active treatments can explain the main causality of the superior prognosis in the high EL group.

Recurrence outcomes after omission of postoperative radiotherapy following breast-conserving surgery for ductal carcinoma in situ of the breast: a multicenter, retrospective study in Korea (KROG 16-02)

PURPOSE

To evaluate the loco-regional recurrence (LRR) rate after breast-conserving surgery without postoperative radiotherapy (RT) for ductal carcinoma in situ (DCIS) of the breast.

METHODS

Between 2000 and 2010, 311 DCIS patients from 9 institutions were analyzed retrospectively. The median age was 47 (range, 20-82). The median tumor size was 7 mm (range, 0.01-76). Margin width was <1 cm in 85 patients (27.3%), and nuclear grade was high in 37 patients (11.9%). Two hundred and three patients (65.3%) received tamoxifen.

RESULTS

With a median follow-up of 74 months (range, 5-189), there were 11 local recurrences (invasive carcinoma in 6 and DCIS in 5) and 1 regional recurrence. The 7-year LRR rate was 3.8%. On univariate analysis, age and margin width were significant risk factors influencing LRR (p = 0.017 and 0.014, respectively). When age and margin width were combined among 211 patients whose margin width were available, the 7-year LRR rates were as follows (p < 0.001): (1) 0% in patients with age >50 years and any margin width status (n = 64), (2) 1.2% in age ≤50 years and margin width ≥1 cm (n = 93), (3) 13.1% in age ≤50 years and margin width <1 cm (n = 54).

CONCLUSIONS

The LRR rate was very low in selected DCIS patients treated with breast-conserving surgery without postoperative RT. However, adjuvant RT should be considered for those with age ≤50 years and margin width <1 cm.