Hyeong Gon Moon

A Serum Protein Profile Predictive of the Resistance to Neoadjuvant Chemotherapy in Advanced Breast Cancers

Prediction of the responses to neoadjuvant chemotherapy (NACT) can improve the treatment of patients with advanced breast cancer. Genes and proteins predictive of chemoresistance have been extensively studied in breast cancer tissues. However, noninvasive serum biomarkers capable of such prediction have been rarely exploited. Here, we performed profiling of N-glycosylated proteins in serum from fifteen advanced breast cancer patients (ten patients sensitive to and five patients resistant to NACT) to discover serum biomarkers of chemoresistance using a label-free liquid chromatography-tandem MS method. By performing a series of statistical analyses of the proteomic data, we selected thirteen biomarker candidates and tested their differential serum levels by Western blotting in 13 independent samples (eight patients sensitive to and five patients resistant to NACT). Among the candidates, we then selected the final set of six potential serum biomarkers (AHSG, APOB, C3, C9, CP, and ORM1) whose differential expression was confirmed in the independent samples. Finally, we demonstrated that a multivariate classification model using the six proteins could predict responses to NACT and further predict relapse-free survival of patients. In summary, global N-glycoproteome profile in serum revealed a protein pattern predictive of the responses to NACT, which can be further validated in large clinical studies.

Proteomic approach reveals FKBP4 and S100A9 as potential prediction markers of therapeutic response to neoadjuvant chemotherapy in patients with breast cancer.

Although doxorubicin (Doxo) and docetaxel (Docet) in combination are widely used in treatment regimens for a broad spectrum of breast cancer patients, a major obstacle has emerged in that some patients are intrinsically resistant to these chemotherapeutics. Our study aimed to discover potential prediction markers of drug resistance in needle-biopsied tissues of breast cancer patients prior to neoadjuvant chemotherapy. Tissues collected before chemotherapy were analyzed by mass spectrometry. A total of 2,331 proteins were identified and comparatively quantified between drug sensitive (DS) and drug resistant (DR) patient groups by spectral count. Of them, 298 proteins were differentially expressed by more than 1.5-fold. Some of the differentially expressed proteins (DEPs) were further confirmed by Western blotting. Bioinformatic analysis revealed that the DEPs were largely associated with drug metabolism, acute phase response signaling, and fatty acid elongation in mitochondria. Clinical validation of two selected proteins by immunohistochemistry found that FKBP4 and S100A9 might be putative prediction markers in discriminating the DR group from the DS group of breast cancer patients. The results demonstrate that a quantitative proteomics/bioinformatics approach is useful for discovering prediction markers of drug resistance, and possibly for the development of a new therapeutic strategy.

Prediction of axillary lymph node metastasis in primary breast cancer patients using a decision tree-based model

BackgroundThe aim of this study was to develop a new data-mining model to predict axillary lymph node (AxLN) metastasis in primary breast cancer. To achieve this, we used a decision tree-based prediction method—the alternating decision tree (ADTree).MethodsClinical datasets for primary breast cancer patients who underwent sentinel lymph node biopsy or AxLN dissection without prior treatment were collected from three institutes (institute A, nu2009=u2009148; institute B, nu2009=u2009143; institute C, nu2009=u2009174) and were used for variable selection, model training and external validation, respectively. The models were evaluated using area under the receiver operating characteristics (ROC) curve analysis to discriminate node-positive patients from node-negative patients.ResultsThe ADTree model selected 15 of 24 clinicopathological variables in the variable selection dataset. The resulting area under the ROC curve values were 0.770 [95% confidence interval (CI), 0.689–0.850] for the model training dataset and 0.772 (95% CI: 0.689–0.856) for the validation dataset, demonstrating high accuracy and generalization ability of the model. The bootstrap value of the validation dataset was 0.768 (95% CI: 0.763–0.774).ConclusionsOur prediction model showed high accuracy for predicting nodal metastasis in patients with breast cancer using commonly recorded clinical variables. Therefore, our model might help oncologists in the decision-making process for primary breast cancer patients before starting treatment.

Risk Factors Associated with Distant Metastasis and Survival Outcomes in Breast Cancer Patients with Locoregional Recurrence

Purpose To decide the optimal treatment for breast cancer patients with locoregional recurrence (LRR), it is important to determine which group has the highest risk of subsequent distant metastasis (DM). We aimed to investigate the factors associated with DM in patients with LRR. Methods We reviewed the data of 208 patients with LRR as the first event after primary surgery for breast cancer at our institution between 1997 and 2010, to identify significant factors associated with DM. Subsequently, Kaplan-Meier curves and the Cox regression method were used to analyze the correlation between clinical factors and survival. Results DM occurred in 33.2% (68/208) of LRR patients. The median DM-free interval was 23 months. Some clinical factors were associated with DM in univariate analysis, including the type of primary surgery (p=0.026), tumor size (p=0.005), nodal status (p=0.011), and administration of initial adjuvant chemotherapy (p=0.001). In addition, regional rather than local recurrence and a disease-free interval (DFI; duration between primary surgery and LRR) ≤30 months were also significant (p<0.001 for both). However, only a shorter DFI reached significance in multiple logistic regression analysis. Cox regression analysis of DM-free survival showed that both a shorter DFI and regional recurrence were significant factors with hazard ratios of 2.1 (95% confidence interval [CI], 1.21-3.65) and 1.85 (95% CI, 1.04-3.28), respectively. Conclusion DFI was the most important factor associated with subsequent DM in patients with LRR as a first event of failure.

Validation of a Scoring System for Predicting Malignancy in Patients Diagnosed with Atypical Ductal Hyperplasia Using an Ultrasound-Guided Core Needle Biopsy

Purpose The need for surgical excision in patients with ultrasound-guided core needle biopsy (CNB)-diagnosed atypical ductal hyperplasia (ADH) remains an issue of debate. The present study sought to validate a scoring system (the U score, for underestimation) that we have previously developed for predicting malignancy in CNB-diagnosed ADH. Methods The study prospectively enrolled 85 female patients with CNB-diagnosed ADH who underwent subsequent surgical excision. Underestimation was defined as a surgical specimen having malignant foci. Results The overall underestimation rate was 37% (31/85). Multivariate analysis showed that a clinically palpable mass, microcalcification on imaging, size >15 mm and a patient age of ≥50 years were independently associated with underestimation. When applied to the scoring system, the validation score was significant (p<0.001; area under the curve, 0.852). No patient with a U score <3.5 had an underestimated lesion. Conclusion The present study successfully validated the efficacy of our scoring system for predicting malignancy in CNB-diagnosed ADH. A U score of ≤3.5 indicates that surgical excision may not be necessary.

Prognostic Influence of BCL2 on Molecular Subtypes of Breast Cancer

Purpose We aimed to reveal the prognostic influence of B-cell CLL/lymphoma 2 (BCL2) on molecular subtypes of breast cancer. Methods We analyzed 9,468 patients with primary breast cancer. We classified molecular subtypes according to the National Comprehensive Cancer Network (NCCN) and St. Gallen guidelines, mainly on the basis of the expression of hormonal receptor (HR), human epidermal growth factor receptor 2 (HER2), and Ki-67. Results Regarding NCCN classification, BCL2 was a strong favorable prognostic factor in the HR(+)/HER2(–) subtype (p<0.001) and a marginally significant favorable prognosticator in the HR(+)/HER2(+) subtype (p=0.046). BCL2 had no prognostic impact on HR(–)/HER2(+) and HR(–)/HER2(–) subtypes. In relation to St. Gallen classification, BCL2 was a strong favorable prognosticator in luminal A and luminal B/HER2(–) subtypes (both p<0.001). BCL2 was a marginally significant prognosticator in the luminal B/HER2(+) subtype (p=0.046), and it was not a significant prognosticator in HER2 or triple negative (TN) subtypes. The prognostic effect of BCL2 was proportional to the stage of breast cancer in HR(+)/HER2(–), HR(+)/HER2(+), and HR(–)/HER2(–) subtypes, but not in HR(–)/HER2(+) subtype. BCL2 was not a prognostic factor in TN breast cancer regardless of epidermal growth factor receptor expression. Conclusion The prognostic influence of BCL2 was different across molecular subtypes of breast cancer, and it was largely dependent on HR, HER2, Ki-67, and the stage of cancer. BCL2 had a strong favorable prognostic impact only in HR(+)/HER2(–) or luminal A and luminal B/HER2(–) subtypes, particularly in advanced stages. Further investigations are needed to verify the prognostic influence of BCL2 on molecular subtypes of breast cancer and to develop clinical applications for prognostication using BCL2.

Efficacy of Exemestane in Korean Patients with Metastatic Breast Cancer after Failure of Nonsteroidal Aromatase Inhibitors

Purpose Exemestane has shown good efficacy and tolerability in postmenopausal women with hormone receptor-positive metastatic breast cancer. However, clinical outcomes in Korean patients have not yet been reported. Methods Data on 112 postmenopausal women with metastatic breast cancer were obtained retrospectively. Clinicopathological characteristics and treatment history were extracted from medical records. All patients received 25 mg exemestane daily until objective disease progression. Progression-free survival (PFS) was the primary endpoint, and secondary endpoints were overall survival (OS), objective response rate (ORR), and clinical benefit rate (CBR=complete response+partial response+stable disease for 6 months). Results The median age of the subjects was 55 years (range, 28-76 years). Exemestane treatment resulted in a median PFS of 5.7 months (95% confidence interval [CI], 4.4-7.0 months) and median OS of 21.9 months (95% CI, 13.6-30.3 months). ORR was 6.4% and CBR was 46.4% for the 110 patients with evaluable lesions. Symptomatic visceral disease was independently associated with shorter PFS (hazard ratio, 3.611; 95% CI, 1.904-6.848; p<0.001), compared with bone-dominant disease in a multivariate analysis of PFS after adjusting for age, hormone receptor, human epidermal growth factor receptor 2, Ki-67 status, dominant metastasis site, and sensitivity to nonsteroidal aromatase inhibitor (AI) treatment. Sensitivity to previous nonsteroidal AI treatment was not associated with PFS, suggesting no cross-resistance between exemestane and nonsteroidal AIs. Conclusion Exemestane was effective in postmenopausal Korean women with hormone receptor-positive metastatic breast cancer who failed previous nonsteroidal AI treatment.

Different prognosis of young breast cancer patients in their 20s and 30s depending on subtype: a nationwide study from the Korean Breast Cancer Society

PurposeNumerous studies have demonstrated that breast cancer in young women (BCY) has unfavorable prognostic features and more unfavorable subtypes. However, few studies have evaluated the effect of subtype disparities on breast cancer prognosis by age, especially for BCY. We analyzed breast cancer mortality stratified by tumor subtype according to age among patients younger than 50xa0years.MethodsData from the Korean Breast Cancer Society Registry for patients diagnosed with invasive breast cancer when aged less than 50xa0years between 2003 and 2010 were reviewed retrospectively.ResultsWe identified 30,793 patients with breast cancer who were eligible for analysis. Of these, 793 (2.6%) were aged 20–29 and 8926 (28.8%) were aged 30–39. Median follow-up duration was 84xa0months. Mean age was 42.4xa0years. Patients in their 20s were more likely to have cancer of advanced stage and higher nuclear grade, present with lymphovascular invasion, and have unfavorable subtypes. Patients in the 20s group showed worse prognosis. In multivariate analysis for overall survival (OS), the hazard ratio (HR) for patients in the 20s group was higher than that for the 30s and 40s groups, and patients with triple-negative breast cancer (TNBC) showed higher HR than patients with HER-2 or luminal subtype (all pxa0<xa00.0001). When stratified by subtype, luminal subtype showed significantly worse prognosis in the 20s group than the 30s and 40s groups, whereas HER-2 and TNBC subtypes showed no significant difference.ConclusionPatients in their 20s with breast cancer had unfavorable characteristics and worse prognosis than patients in their 30s and 40s. When stratified by tumor subtype, patients in their 20s with luminal subtype of breast cancer showed worse prognosis than older patients, whereas HER-2 and TNBC subtypes showed no significant differences.

Malignant and borderline phyllodes tumors of the breast: a multicenter study of 362 patients (KROG 16-08)

PurposeTo identify risk factors for local recurrence (LR) and investigate roles of adjuvant local therapy for malignant and borderline phyllodes tumors of the breast.MethodsFrom 1981 to 2014, 362 patients with malignant (nu2009=u2009235) and borderline (nu2009=u2009127) phyllodes tumors were treated by breast-conserving surgery (BCS) or total mastectomy (TM) at 10 centers. Thirty-one patients received adjuvant radiation therapy (RT), and those who received adjuvant chemotherapy were excluded from the study.ResultsMedian follow-up was 5xa0years. LR developed in 60 (16.6%) patients. Regional recurrence occurred in 2 (0.6%) patientsxa0and distant metastasisxa0(DM) developed in 19 (5.2%) patients. Patients receiving BCS (pu2009=u20090.025) and those not undergoing adjuvant RT (pu2009=u20090.041) showed higher LR rates. For malignant subtypes, local control (LC) rates at 5 years for BCS alone, BCS with adjuvant RT, TM alone, and TM with adjuvant RT were 80.7, 93.3, 92.4, and 100%, respectively (pu2009=u20090.033). Multivariate analyses revealed BCS alone, tumoru2009sizexa0≥u20095xa0cm, and positive margins as independent risk factors for LR. Margin-positive BCS alone showed poorest LC regardless of tumor size (62.5%, pu2009=u20090.007). For margin-negative BCS alone, 5-year LC rates for tumorsu2009≥u20095xa0cm versus thoseu2009<u20095xa0cm were 71.8% versus 89.5% (pu2009=u20090.012). For borderline subtypes, only positive margins (pu2009=u20090.044) independently increased the risk of LR. DM developed exclusively in malignant subtypes and a prior LR event increased the risk of DM by sixfold (HR 6.2, 95% CI 1.6–16.1, pu2009=u20090.001).ConclusionsMalignant and borderline phyllodes tumors with positive margins after surgery have high LR rates. After treatment by margin-negative BCS alone, patients with large malignant phyllodes tumorsu2009≥u20095xa0cm also have heightened risk of LR. Thus, such patients should be considered for additional local therapy.