Prognosis according to the timing of recurrence in breast cancer

Purpose@#Clinically, breast cancer can be divided into 4 subtypes based on the presence of hormone receptors, human epidermal growth factor receptor 2 (HER2), and Ki-67. Because the pattern and time of recurrence vary according to the subtype, we evaluated whether there was a difference in overall survival (OS) among the subtypes according to the time and type of recurrence. @*Methods@#A total of 2,730 patients who underwent breast cancer surgery were analyzed. Early and late recurrence were defined as recurrence within and after 5 years of diagnosis, respectively. Recurrence type was categorized as locoregional recurrence or systemic recurrence. @*Results@#Hormone receptor-positive tumors were significantly more frequent in the late recurrence group than in the early recurrence group (estrogen receptor positive, 47.8% [early] vs. 78.7% [late]). However, there was no difference in the rate of HER2 overexpression (HER2+, 38.1% [early] vs.39.0% [late]). In subgroup analysis, early recurrence was a significant prognostic factor for OS in all subtypes. However, late recurrence was a significant prognostic factor for OS only in the luminal B subtype (hazard ratio of 4.30). In addition, the luminal B type had the highest proportion in late recurrence patients (63.2%). @*Conclusion@#The luminal B subtype had a high rate of late recurrence, and late recurrence was a poor prognostic factor for OS only in this subgroup. Therefore, further targeted treatments for luminal B breast cancer are needed and patients with this subtype require close long-term surveillance.

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.

Breast Cancer Statistics in Korea, 2018 / 한국유방암학회지

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.

Breast Cancer Statistics in Korea, 2018 / 한국유방암학회지

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.

Differences in prognosis by p53 expression after neoadjuvant chemotherapy in triple-negative breast cancer

Purpose@#Our previous studies suggested that p53-positive triple-negative breast cancer (TNBC) should be more sensitive to chemotherapy than p53-negative TNBC. The aim of this study was to determine whether p53 expression in TNBC could predict response to neoadjuvant chemotherapy and the resulting prognosis. @*Methods@#From January 2009 to December 2017, TNBC patients who underwent neoadjuvant chemotherapy were reviewed, including a total of 31 TNBC patients who had clinical lymph node metastasis. The status of p53 expression in patients before and after chemotherapy was evaluated. @*Results@#Two patients (22.2%, 2 of 9) achieved pCR in p53(+) TNBC and 4 patients (50%, 5 of 10) achieved pCR in p53(-) TNBC. There was no correlation between pCR rate and p53 expression (P = 0.350). Based on prechemotherapy p53 expression, there was no significant difference in disease-free survival (DFS) between p53(+) TNBC and p53(-) TNBC (P = 0.335). However, after chemotherapy, p53(+) TNBC had shown higher DFS than p53(-) TBNC (P = 0.099). Based on prechemotherapy p53 expression, p53(+) TNBC had better overall survival (OS) than p53(-) TNBC, but the difference was not statistically significant (P = 0.082). After chemotherapy, p53(+) TNBC showed significantly better OS than p53(-) TNBC (P = 0.018). @*Conclusion@#Immunohistochemically detected p53 expression in TNBC could not predict the response to neoadjuvant chemotherapy. However, p53(+) TNBC had a better OS than p53(-) TNBC in patients who underwent neoadjuvant chemotherapy.

Differences in prognosis by p53 expression after neoadjuvant chemotherapy in triple-negative breast cancer

Purpose@#Our previous studies suggested that p53-positive triple-negative breast cancer (TNBC) should be more sensitive to chemotherapy than p53-negative TNBC. The aim of this study was to determine whether p53 expression in TNBC could predict response to neoadjuvant chemotherapy and the resulting prognosis. @*Methods@#From January 2009 to December 2017, TNBC patients who underwent neoadjuvant chemotherapy were reviewed, including a total of 31 TNBC patients who had clinical lymph node metastasis. The status of p53 expression in patients before and after chemotherapy was evaluated. @*Results@#Two patients (22.2%, 2 of 9) achieved pCR in p53(+) TNBC and 4 patients (50%, 5 of 10) achieved pCR in p53(-) TNBC. There was no correlation between pCR rate and p53 expression (P = 0.350). Based on prechemotherapy p53 expression, there was no significant difference in disease-free survival (DFS) between p53(+) TNBC and p53(-) TNBC (P = 0.335). However, after chemotherapy, p53(+) TNBC had shown higher DFS than p53(-) TBNC (P = 0.099). Based on prechemotherapy p53 expression, p53(+) TNBC had better overall survival (OS) than p53(-) TNBC, but the difference was not statistically significant (P = 0.082). After chemotherapy, p53(+) TNBC showed significantly better OS than p53(-) TNBC (P = 0.018). @*Conclusion@#Immunohistochemically detected p53 expression in TNBC could not predict the response to neoadjuvant chemotherapy. However, p53(+) TNBC had a better OS than p53(-) TNBC in patients who underwent neoadjuvant chemotherapy.

Breast Cancer Statistics in Korea in 2017: Data from a Breast Cancer Registry / 한국유방암학회지

This article describes the breast cancer statistics in Korea, including the incidence, type of surgical procedure, stage, and molecular subtype, using the Korean Breast Cancer Society (KBCS) and Korea Central Cancer Registry data. There were a total of 26,534 new breast cancer diagnoses in 2017 in Korea, of which 4,139 were carcinoma in situ cases and 22,395 were invasive cancer cases. The age standardized rate of breast cancer was 75.3 per 100,000 women in 2017 (63.0 of invasive carcinoma and 12.3 of carcinoma in situ), and it has been steadily increasing across all age groups. Breast cancer occurred most commonly in the 40–49 age group. Compared to 2016, breast conserving surgery (BCS) has increased, and 67.4% of patients were treated with BCS in 2017. The proportions of stage 0 and stage I have continued to increase, accounting for 60.7%. The most common subtype of breast cancer was hormone receptor (HR) positive and human epidermal growth factor receptor-2 (HER2) negative type comprising 65.9% of the cases, whereas HR negative and HER2 positive type was the rarest comprising 10.2% of the cases. The 5-year relative survival rate of breast cancer patients had increased by 14.0% from 79.2% in 1993–1995 to 93.2% in 2013–2017. It is essential to actively enter breast cancer data into the KBCS registry to improve our understanding.

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

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.

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

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 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.

Fertility Rates in Young Korean Breast Cancer Patients Treated with Gonadotropin-Releasing Hormone and Chemotherapy / 한국유방암학회지

PURPOSE: Gonadotropin-releasing hormone (GnRH) agonists have been used with adjuvant chemotherapy to protect ovarian function. However, there are no data on the actual pregnancy rates among young breast cancer patients receiving GnRH agonists and concurrent chemotherapy in Korea. METHODS: Among patients who underwent surgery from January 2002 to April 2012, premenopausal patients aged between 20 and 40 years were included in the analysis. We retrospectively reviewed clinicopathologic features (e.g., age, obstetric and menstruation history), recurrence, and survival status. The rate of resumption of menstruation was calculated in all patients. In the married group, pregnancy and delivery rates were also recorded. RESULTS: Among 101 patients, 19 were lost to follow-up and 82 were eligible for the analysis. Among them, 31 were married, 10 of 51 got married, and 41 remained unmarried through the follow-up period. Among the married patients, 15 became pregnant and gave birth to 19 babies, whereas 26 did not become pregnant. The pregnancy rate in the married group was 50.0% (15/30). Three of 15 pregnancies (20.0%) were multiparous. Most of the delivered babies were healthy and 80.0% of patients had no problems breastfeeding (12/15). More than half the patients in all groups recovered menstrual status within 12 months. CONCLUSION: Fifty percent of young breast cancer patients who attempted pregnancy succeeded in pregnancy after adjuvant chemotherapy and GnRH agonists. Further studies that include control groups are required to confirm whether the use of GnRH agonists improves pregnancy.

Erratum: Validation of a Web-Based Tool to Predict the Ipsilateral Breast Tumor Recurrence (IBTR! 2.0) after Breast-Conserving Therapy for Korean Patients / 한국유방암학회지

This article was published with a misspelled the date of acceptance. The date of acceptance should be corrected as “March 7, 2013”.

Comparison of Prognosis according to Tumor Size in Small Breast Cancer with Lymph Node Involvement

PURPOSE: Larger tumor size and more extensive lymph node (LN) involvement have been considered independent factors for poor prognosis of breast cancer. We evaluated whether smaller tumor size may be a factor of worse prognosis compared with larger tumor size in small-sized breast cancer with LN involvement. METHODS: A retrospective analysis was conducted at a single center for 1,400 patients with small-sized (≤2 cm) and LN involved (N1–N3) breast cancer who underwent radical surgery, had no distant metastases, and were diagnosed between 2004 and 2014. We subdivided their tumor size into four subgroups (T1mi, T1a, T1b, T1c) graded using the 7th American Joint Committee on Cancer staging and two subgroups (T1ab [≤1 cm] and T1c [>1 cm]) divided by tumor size. The relationship between tumor size, prognosis and specific features were analyzed using the Chi-square test, Kaplan-Meier method, and Cox regression analysis. RESULTS: There were significant differences in estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2) and HER2 amplified type among the four subgroups in all patients. Especially, HER2-amplified type also appeared in distribution significantly between the two subgroups in all patients (T1ab [13.0%] vs. T1c [8.0%], p=0.008). The overall survival of the T1N1 staged patients in the smaller-sized tumor group (T1ab) was lower than that of those in the larger-sized group (T1c) (p=0.005). In the multivariate Cox regression analysis of all patients, the T1ab group showed a higher mortality risk compared with the T1c group (adjusted hazard ratio, 2.540; 95% confidence interval, 1.195–5.397; p=0.015). CONCLUSION: Smaller-sized tumors with LN involvement indicated worse prognosis compared with larger-sized tumors.

Association between Mutation and Expression of TP53 as a Potential Prognostic Marker of Triple-Negative Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: TP53, the most frequently mutated gene in breast cancer, is more frequently altered in HER2-enriched and basal-like breast cancer. However, no studies have clarified the role of TP53 status as a prognostic and predictive marker of triple-negative breast cancer (TNBC). MATERIALS AND METHODS: We performed p53 immunohistochemistry (IHC), nCounter mRNA expression assay, and DNA sequencing to determine the relationship between TP53 alteration and clinical outcomes of TNBC patients. RESULTS: Seventy-seven of 174 TNBC patients were found to harbor a TP53 mutation. Patients with missense mutations showed high protein expression in contrast to patients with deletion mutations (positivity of IHC: wild type vs. missense vs. deletion mutation, 53.6% vs. 89.8% vs. 25.0%, respectively; p < 0.001). TP53 mRNA expression was influenced by mutation status (mRNA expression [median]: wild type vs. missense vs. deletion mutation, 207.36± 132.73 vs. 339.61±143.21 vs. 99.53±99.57, respectively; p < 0.001). According to survival analysis, neither class of mutation nor protein or mRNA expression status had any impact on patient prognosis. In subgroup analysis, low mRNA expression was associated with poor prognosis in patients with a TP53 missense mutation (5-year distant recurrence-free survival [5Y DRFS]: low vs. high, 50.0% vs. 87.8%; p=0.009), while high mRNA expression with a TP53 deletion mutation indicated poor prognosis (5Y DRFS: low vs. high, 91.7% vs. 75.0%; p=0.316). CONCLUSION: Association between TP53 mutation and expression indicates a potential prognostic marker of TNBC; hence both DNA sequencing and mRNA expression analysis may be required to predict the prognosis of TNBC patients.

Clinicopathologic Features and Long-Term Outcomes of Elderly Breast Cancer Patients: Experiences at a Single Institution in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to assess the tumor characteristics and long-term clinical outcomes of adjuvant treatments after surgery with a curative aim for patients with breast cancer who are 65 years and older. MATERIALS AND METHODS: Patients with breast cancer who underwent curative surgery from 2000 to 2009 were analyzed (n=4,388). Tumor characteristics and survival outcome were compared by dividing the patients into two age groups (< 65 and ≥ 65 years old). The Kaplan-Meier method was used for comparison of survival rates by log-rank test, and a Cox regression model was used to examine the effect of variables. RESULTS: Among 4,388 patients with invasive breast cancer, 317 patients (7.2%) were 65 years or older and the median age of all patients was 47 years (range, 18 to 91 years). Tumor characteristics were similar between the two age groups, but the older patients were treated less often with adjuvant treatments. During a median follow-up period of 122 months, recurrence-free survival (RFS) was equivalent for patients 65 years and older compared to younger patients, but significantly worse in overall survival (OS) and breast cancer–specific survival (BCSS) (5-year OS, 94.3% vs. 90.5%; p < 0.001 and 5-year BCSS, 94.7% vs. 91.8%; p=0.031). In the multivariate model, age ≥ 65 years old was identified as an independent risk factor for OS and RFS. CONCLUSION: Elderly breast cancer appeared to have worse outcomes with very low prevalence in Korea, despite similar tumor characteristics. More active adjuvant therapies would have a role for aggressive subtypes for fit, elderly patients.

Sentinel Lymph Node Biopsy Alone after Neoadjuvant Chemotherapy in Patients with Initial Cytology-Proven Axillary Node Metastasis / 한국유방암학회지

PURPOSE: Neoadjuvant chemotherapy (NAC) has been recently used to downstage breast cancer. However, in patients with initial axillary lymph node (ALN) metastasis, ALN dissection regardless of the NAC response remains the standard treatment. The purpose of this study was to identify the feasibility and accuracy of sentinel lymph node biopsy (SLNB) after NAC in patients with ALN metastasis at diagnosis. METHODS: From January 2007 to August 2013, data of patients who were diagnosed with invasive breast cancer and ALN metastasis and treated with NAC followed by definitive surgery in two centers were collected retrospectively. A total of 386 patients were enrolled and classified into five groups according to surgical procedure for the ALNs and pathologic results. RESULTS: At SLNB after NAC, sentinel lymph nodes (SLNs) that stained blue or were hot, including suspicious nodes, were identified; the SLN identification and false-negative rates was 96% and 10%, respectively. There was no difference in the overall survival among the groups. For patients who revealed a pathologic complete node response, there was a significant difference in the disease-free survival rate between the SLNB only and complete ALN dissection groups (p=0.031). However, the rate of axillary recurrence demonstrated no significant differences among the groups (p>0.050). CONCLUSION: SLNB after NAC in breast cancer patients with initial ALN metastasis may help identify downstaging to negative nodal status and thereby reduce the surgical morbidity by avoiding standard ALN dissection.

Independent Prognostic Factors for Overall Survival after Salvage Operation for Ipsilateral Breast Tumor Recurrence Following Breast-Conserving Surgery / 한국유방암학회지

PURPOSE: Few studies address independent prognostic factors after ipsilateral breast tumor recurrence (IBTR) following breast-conserving surgery (BCS). Locoregional recurrence is associated with distant metastases and increased mortality rates. Therefore anticipating prognoses after IBTR and evaluating risk factors for overall survival following a second salvage operation are important. We evaluated independent prognostic factors affecting overall survival after a second operation for IBTR. METHODS: We retrospectively identified 11,073 patients who underwent breast cancer surgery between November 1995 and December 2011. Locoregional recurrence occurred in 787 patients. Among them, IBTR developed in 165 patients selected for analysis. Excluding eight patients who refused further treatment, we analyzed 157 patients who underwent a second operation (partial mastectomy, 28 [17.8%]; total mastectomy, 129 [82.2%]) for IBTR. Excluding 26 patients with incomplete data, we evaluated the clinicopathol-ogical features influencing overall survival at the first and the second operation in the 131 patients who underwent a second operation. RESULTS: The median age of patients at the first operation was 43.6 years (range, 27-69 years). The median duration from the first to the second operation was 45.0 months (range, 2.5-164.6 months). The 5-year overall survival rate after IBTR was 87.1%. In the multivariable analyses, duration from the first to the second operation, histopathology, lymph node status, and adjuvant chemotherapy, radiotherapy, and endocrine therapy at the first operation were independent prognostic factors for overall survival. Positive estrogen receptor status and endocrine therapy at the second operation were also associated with increased overall survival following salvage operations for IBTR. CONCLUSION: The time interval to IBTR following BCS is related to overall survival after salvage operation for IBTR and it is important to undergo optimal adjuvant treatments according to risk factors after the first operation because those risk factors affect overall survival for IBTR following BCS.

The Clinical Impact of 21-Gene Recurrence Score on Treatment Decisions for Patients with Hormone Receptor-Positive Early Breast Cancer in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The 21-gene (Oncotype DX) recurrence score (RS) assay is useful in predicting the benefits of adjuvant chemotherapy for early breast cancer patients and is widely used in Western countries. However, to date, it has not gained much popularity in East Asia. We analyzed the results from five institutions' experience from using the 21-gene assay and examined the impact of assay results on decision making of chemotherapy in Korean breast cancer patients and the associations between RS and clinicopathologic characteristics. MATERIALS AND METHODS: The 21-gene assay was performed on 212 patients with estrogen receptor-positive early breast cancer in five institutions. Each center made systemic treatment decisions both before and after the knowledge of assay results. RESULTS: Among the 212 patients, 132 (62.3%) had a low RS of or = 31. Histologic grade, presence of micrometastases, Ki-67, and presence of lymphatic invasion were statistically associated with the RS results. Treatment decisions were changed in 115 of 212 patients (54.2%) in 109 of 212 (51.4%) from chemotherapy plus hormone therapy to hormone therapy, and in six of 212 (2.8%) from hormone therapy to chemotherapy plus hormone therapy. CONCLUSION: The 21-gene breast cancer assay proved to have a significant impact on treatment decision- making. The test reduces chemotherapy use in more than 50% of Korean estrogen receptor-positive, early breast cancer patients.

Validation of a Web-Based Tool to Predict the Ipsilateral Breast Tumor Recurrence (IBTR! 2.0) after Breast-Conserving Therapy for Korean Patients / 한국유방암학회지

PURPOSE: IBTR! 2.0 is a web-based nomogram that predicts the 10-year ipsilateral breast tumor recurrence (IBTR) rate after breast-conserving therapy. We validated this nomogram in Korean patients. METHODS: The nomogram was tested for 520 Korean patients, who underwent breast-conserving surgery followed by radiation therapy. Predicted and observed 10-year outcomes were compared for the entire cohort and for each group, predefined by nomogram-predicted risks: group 1, 10%. RESULTS: In overall patients, the overall 10 year predicted and observed estimates of IBTR were 5.22% and 5.70% (p=0.68). In group 1, (n=124), the predicted and observed estimates were 2.25% and 1.80% (p=0.73), in group 2 (n=177), 3.95% and 3.90% (p=0.97), in group 3 (n=181), 7.14% and 8.80% (p=0.42), and in group 4 (n=38), 11.66% and 14.90% (p=0.73), respectively. CONCLUSION: In a previous validation of this nomogram based on American patients, nomogram-predicted IBTR rates were overestimated in the high-risk subgroup. However, our results based on Korean patients showed that the observed IBTR was higher than the predicted estimates in groups 3 and 4. This difference may arise from ethnic differences, as well as from the methods used to detect IBTR and the healthcare environment. IBTR! 2.0 may be considered as an acceptable nomogram in Korean patients with low- to moderate-risk of in-breast recurrence. Before widespread use of this nomogram, the IBTR! 2.0 needs a larger validation study and continuous modification.

Neoadjuvant human epidermal growth factor receptor-2 targeted therapy in patients with locally advanced breast cancer / 대한외과학회지

PURPOSE: We analyzed the responses of patients with locally advanced breast cancer to neoadjuvant chemotherapy (NAC) and NAC combined with neoadjuvant human epidermal growth factor receptor-2 (HER2) targeted therapy (NCHTT). METHODS: We retrospectively reviewed 59 patients with HER2 amplified locally advanced breast cancer among patients who were treated surgically after neoadjuvant therapy at Samsung Medical Center between 2005 and 2009. Thirty-one patients received conventional NAC and 28 patients received NCHTT. Pathologic responses were assessed according to response evaluation criteria in solid tumors (RECIST) guidelines. RESULTS: Pathologic complete response (pCR) was achieved in 13 out of 28 patients treated with NCHTT and in 6 out of 31 patients treated with NAC alone (46.4% vs. 19.4%, respectively, P = 0.049). Breast conserving surgery (BCS) was more frequently performed in the NCHTT group than in the NAC only group (71.4% vs. 19.4%, P < 0.001). The 3-year recurrence-free survival (RFS) rate was 100% in the NCHTT group and 76.4% in the NAC group (P = 0.014). Together, NCHTT, type of operation (BCS vs. mastectomy) and pathologic nodal status were significant prognostic factors for RFS in univariate analysis. CONCLUSION: We found that NCHTT produced higher pCR rates than NAC alone in locally advanced breast cancer.

Aromatase inhibitor-associated musculoskeletal symptoms: incidence and associated factors / 대한외과학회지

PURPOSE: Arthralgia is the most common side effect in breast cancer patients receiving aromatase inhibitor (AI) therapy. Few studies have evaluated the risk factors, onset, and incidence of musculoskeletal pain in these patients. This study identifies the risk factors of AI-related severe arthralgia and their prevalence. METHODS: All the clinical and pathological records of postmenopausal patients diagnosed with invasive breast cancer using AI at Samsung Medical Center from January 2005 to November 2007 were reviewed. Multivariate logistic regression analyses were performed to evaluate the risk factors of AI-associated musculoskeletal symptoms (AIMSS) and factors associated with AI discontinuance. RESULTS: Among 299 patients, 69 patients (23%) experienced musculoskeletal symptoms attributed to AI use. In multivariate logistic regression analysis, no statistically significant outcome was found to confirm the risk factors for the development of AIMSS. Among the 69 patients who experienced AI-associated musculoskeletal symptoms, 29 (39.7%) discontinued AI use. Multivariate logistic regression analyses revealed an association of prior tamoxifen use with discontinuance of AI (P < 0.01; odds ratio, 4.27; 95% confidence interval, 1.74 to 10.50). CONCLUSION: Prior use of tamoxifen is related to discontinuation of AI due to AI-associated severe arthralgia. Special monitoring and proper pain control for these patients should be considered during the treatment period.