Heung Kyu Park

The Basic Facts of Korean Breast Cancer in 2012: Results from a Nationwide Survey and Breast Cancer Registry Database

The Korean Breast Cancer Society (KBCS) has reported a nationwide breast cancer data since 1996. We present a comprehensive report on the facts and trends of breast cancer in Korea in 2013. Data on the newly diagnosed patients in the year 2013 were collected from 99 hospitals by using nationwide questionnaire survey. Clinical characteristics such as stage of cancer, histologic types, biological markers, and surgical management were obtained from the online registry database. A total of 19,316 patients were newly diagnosed with breast cancer in 2013. The crude incidence rate of female breast cancer including carcinoma in situ was 76.2 cases per 100,000 women. The median age at diagnosis was 50 years, and the proportions of postmenopausal women with breast cancer accounted for more than half of total patients. The proportion of early breast cancer increased consistently, and the pathologic features have changed accordingly. Breast-conserving surgery was performed in more cases than total mastectomy in the year. The total number of breast reconstruction surgeries markedly increased approaching 3-fold in last 11 years. According to annual percentile change of invasive cancer incidence, the incidence increased rapidly until 2010. And thereafter the increase of it became steadier. For ductal carcinoma in situ, the incidence consistently increased during the same period without any joinpoint. Analysis of nationwide registry data will contribute to defining of the trends and characteristics of breast cancer in Korea.

Nation-Wide Korean Breast Cancer Data from 2008 Using the Breast Cancer Registration Program

Purpose Since 1996, the Korean Breast Cancer Society has collected nation-wide breast cancer data and analyzed the data using their online registration program biannually. The purpose of this study was to evaluate the characteristics of Korean breast cancer from 2008 and examine chronological based patterns. Methods Data were collected from 38 medical schools (67 hospitals), 20 general hospitals, and 10 private clinics. The data on the total number, gender, and age distribution were collected through a questionnaire as well as other detailed data analyzed via the online registration program. Results In 2008, there were 13,908 patients who were newly diagnosed with breast cancer. The crude incidence rate of female breast cancer was 57.3 among 100,000 and the median age was 49 years. The age distribution had not changed since the initial survey; however the proportion of postmenopausal patients had increased and median age was older than the past. In staging distribution, the proportion of early breast cancer (stage 0, I) was 47.2% with, breast-conserving surgery performed in 58% and mastectomy in 39.5%. Conclusion Compared to past data, the incidence of breast cancer in Korea continues to rise. Furthermore, the proportion of those detected by screening and breast conservation surgery has increased remarkably. To understand the patterns of Korean breast cancer, the nation-wide data should continuously investigated.

Ki-67 as a Predictor of Response to Neoadjuvant Chemotherapy in Breast Cancer Patients

Purpose The objectives of this study were to assess the potential value of Ki-67 in predicting response to neoadjuvant chemotherapy in breast cancer patients and to suggest a reasonable cutoff value for classifying Ki-67 expression. Methods This study included 74 breast cancer patients who underwent surgery after anthracycline-based neoadjuvant chemotherapy between 2007 and 2012. We analyzed the clinical and immunohistochemical characteristics using core biopsy specimens obtained before neoadjuvant chemotherapy to determine their correlations with the response to chemotherapy. Results A clinical complete response was observed in 6 patients (8.1%); a clinical partial response, in 44 patients (59.5%); and clinical stable disease, in 24 patients (32.4%). A pathologic complete response (pCR) was observed in 10 patients (13.5%). In univariate analysis, estrogen receptor (ER) negativity (p=0.031), human epidermal growth factor receptor 2 (HER2) positivity (p=0.040), and high Ki-67 expression (p=0.036) were predictive factors for a pCR. In multivariate analysis, Ki-67 was the only independent predictor of a pCR (p=0.049). The analysis of Ki-67 values revealed that 25% was a reasonable cutoff value for predicting the response to chemotherapy. In subgroup analysis, a higher Ki-67 value (≥25%) was a significant predictive factor for the response to neoadjuvant chemotherapy, especially in ER-negative and HER2-positive breast cancer patients. Conclusion Ki-67 expression in breast cancer tissue may be an effective factor for predicting the response to neoadjuvant chemotherapy. We suggest that a 25% level of Ki-67 expression is a reasonable cutoff value for predicting a response to chemotherapy. Moreover, Ki-67 is a useful predictive factor for pCR, especially in patients with ER-negative and HER2-positive breast cancer.

Breast Sonographic Elastography Using an Advanced Breast Tissue-Specific Imaging Preset Initial Clinical Results

The purpose of this study was to evaluate the interpretation criteria, such as the size ratio, stain ratio, and elasticity score, and to assess the diagnostic performance of sonographic elastography by using an advanced breast tissue‐specific imaging preset compared with that of conventional sonography for the differentiation of benign and malignant breast masses.

The Risk Factors Influencing between the Early and Late Recurrence in Systemic Recurrent Breast Cancer

Purpose Patients with recurrent breast cancer usually die of their disease, even after radical surgery and adjuvant therapies which could reduce the odds of dying. Many studies analyzed and compared patients who died of recurrent disease with those that died without recurrent disease. However, less attention has been paid to evaluating factors associated with the timing of recurrence. Thus, the objective of this study is to investigate the correlation between various factors and the timing of recurrence. Methods We retrospectively reviewed the data of 95 recurrent breast cancer patients who underwent curative surgery to determine the prognostic factors such as menopausal status, operation method, stage, nodal status, histologic grade, nuclear grade, extensive intraductal carcinoma component, hormone receptor, p53, c-erbB-2, Ki-67, and molecular subtype. We had attempted to compare the recurrent patients within 2 years after operation and adjuvant chemotherapies as the early recurrence with those over 2 years as the late recurrence. Results Histologic grade (p=0.005), nuclear grade (p<0.001), p53 (p=0.022), and Ki-67 (p<0.001) were significant different factors that influenced the systemic recurrence between early recurrence and late recurrence. In stage I/II, histologic grade (p=0.001), nuclear grade (p<0.001), and Ki-67 (p=0.005) were significant factors that influenced the systemic early recurrence. In stage III, nuclear grade (p=0.024), and Ki-67 (p=0.001) were significant factors that influenced the systemic early recurrence. But subtypes (p=0.189, p=0.132, p=0.593, p=0.083) are not associated with the timing of recur rence. Conclusion In systemic recurrent breast cancer patients, the risk factors such as histologic grade, nuclear grade, p53 and Ki-67 are also associated with the timing of recurrence. We sug gest that these patients should be proper treated and be closely followed up.

Eccrine spiradenoma arising in the breast misdiagnosed as an epidermal inclusion cyst.

Eccrine spiradenomas are rare, benign, cutaneous tumors that originate in the sweat glands. Eccrine spiradenomas in the breast are very rare and only a few cases have been reported. We report here on the case of a 47-year-old woman with superficial masses in the breast and these masses had gradually increased in size during follow-up. They were confirmed to be an eccrine spiradenoma on pathologic examination. There have been a few reports about the radiologic findings of eccrine spiradenomas of the breast. This is the first case of an eccrine spiradenoma in the breast that was characterized by multiple imaging modalities, including mammography, ultrasonography and MRI. The lesion in our patient was first diagnosed as an epidermal inclusion cyst based on the imaging findings and the masss superficial location. Although the mammographic and ultrasonographic imaging findings of eccrine spiradenomas and epidermal inclusion cysts are similar, the MRI findings are different between epidermal inclusion cysts and eccrine spiradenomas. Eccrine spiradenomas should be considered in the differential diagnosis of cutaneous and subcutaneous lesions of the breast.

A comparison of the clinical outcomes of patients with invasive lobular carcinoma and invasive ductal carcinoma of the breast according to molecular subtype in a Korean population

BackgroundTo investigate the clinicopathological characteristics and the survival outcomes of invasive lobular carcinoma (ILC) patients compared to invasive ductal carcinoma (IDC) patients according to their molecular subtype.MethodsWe compared the clinicopathological characteristics, breast cancer-specific survival (BCSS) and overall survival (OS) between patients with IDC (n = 14,547) and ILC (n = 528).ResultsThe ILC presented with a larger tumor size, more advanced cancer stage, increased rate of hormonal receptor positivity, human epidermal growth factor 2 (HER2) negativity and mastectomy than the IDC. The ILC patients more frequently presented with the luminal A subtype, whereas the IDC patients more frequently presented with the luminal B, HER2-overexpression, or triple negative subtype. The BCSS and OS were not significantly different between the IDC and ILC for each molecular subtype.ConclusionsSimilar to IDC patients, molecular subtype should be considered when determining the prognosis and treatment regimen for ILC patients.

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

PurposeThe 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.MethodsA 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.ResultsA 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.ConclusionsWe 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.

Prognostically Distinctive Subgroup in Pathologic N3 Breast Cancer

Purpose The aim of this retrospective study was to investigate whether there are prognostically different subgroups among patients with pathologic N3 (pN3) breast cancer. Methods The records of 220 patients who underwent surgery for pN3 breast cancer from January 2006 to September 2012 were reviewed. All patients received adjuvant therapy according to standard protocols. The primary outcome was disease-free survival (DFS). Results Patients were followed for a median time of 68.3 months after their primary surgery (range, 10–122 months), during which time 75 patients (34.1%) had developed disease recurrence and 48 patients (21.8%) had died. The DFS and overall survival were 67.8% and 86.1%, respectively, at 5 years. Multiple logistic regression analysis showed that young age (<35 years, p=0.009), high serum neutrophil/lymphocyte ratio (>3.0) (p=0.020), high nodal ratio (number of metastatic lymph nodes divided by number of removed nodes) (>0.65) (p=0.062), and molecular phenotype (p=0.012) were significantly associated with tumor recurrence. Tumor biological subtype was the most significant predictor of recurrence. The 5-year DFS rates in patients with hormone receptor (HR) positive and human epidermal growth factor receptor 2 (HER2) negative, HR+HER2+, HR–HER2+, and triple negative subtypes were 82%, 63%, 58%, and 37%, respectively. Conclusion Clinical outcomes of patients with extensive nodal metastasis were heterogeneous in terms of prognosis. Tumor biological subtype was the most important prognostic factor for pN3 disease. The prognosis of patients with HR+HER2– subtype in pN3 breast cancer was similar to that of patients with stage II breast cancer.

Is radiotherapy necessary for intermediate risk ductal carcinoma in situ after breast conserving surgery

Identifying ductal carcinoma in situ (DCIS) patients at highest risk for recurrence after breast conserving surgery (BCS) remains a clinical concern. Subjecting all such patients to radiotherapy may be unnecessary. The Van Nuys Prognostic Index (VNPI) is a simple scoring system for predicting the risk of local recurrence in patients with DCIS. We reviewed patients with DCIS applying the VNPI score system. A total of 184 DCIS patients who underwent surgery at our institution between January 2003 and December 2011 were identified. Patients were not treated according to VNPI guidelines; rather, radiation therapy was applied at each surgeon’s discretion. All patients with hormonal receptor positive tumors were treated with hormonal therapy. Pathology reports were reviewed and VNPI scores of each DCIS calculated. Of the 184 patients, 52 (28.3%), 115 (62.5%) and 17 (9.2%) had low, intermediate and high VNPI scores, respectively. Six of the 184 patients (3.3%) developed ipsilateral local recurrence, five in the intermediate and one in the high VNPI score group. Of the five in the intermediate group, three (60%) were in patients with ER-negative tumors. VNPI score itself was not associated with recurrence (P = 0.145). Factors associated with recurrence included tumor size (hazard ratio [HR] 6.88), grade (HR 9.07) and hormone receptor status (HR 11.75). Radiotherapy did not significantly improve recurrence rates in patients with low and intermediate risk DCIS, especially in those with ER-positive tumors. Radiotherapy can be omitted in patients with ER-positive intermediate score DCIS and in patients with low score DCIS.