Publications by authors named "Sung Gwe Ahn"
Background: In HER2+ early breast cancer (EBC), we investigated tumor and immune changes during neoadjuvant treatment and their impact on residual disease (RD) biology and prognostic implications across 4 neoadjuvant studies of trastuzumab with or without lapatinib, and with or without chemotherapy: CALGB 40601, PAMELA, NeoALTTO and NSABP B-41.
Patients And Methods: We compared tumor and immune gene expression changes during neoadjuvant treatment and their association with with event-free survival (EFS) by uni- and multivariable Cox regression models in different cohorts and timepoints: 452 RD samples at baseline including 169 with a paired RD, and biomarker changes during neoadjuvant therapy, evaluating model performance via the c-index.
Results: Analysis of 169 paired tumor samples revealed a shift in intrinsic subtype proportions from HER2-Enriched at baseline (50.
Background: Immunochemotherapy with pembrolizumab has been integrated into clinical practice as part of the standard-of-care for non-metastatic triple-negative breast cancer (TNBC) with high risk. We conducted a real-world study in TNBC patients treated with neoadjuvant chemotherapy to compare pathologic complete response (pCR) rates relative to stromal tumor-infiltrating lymphocytes (sTIL) across different regimens: non-carboplatin, carboplatin-, and pembrolizumab-chemotherapy.
Patients And Methods: We analyzed a cohort of 450 patients with TNBC who underwent surgery following neoadjuvant chemotherapy between March 2007 and February 2024.
Background: The mutation is one of the most frequently identified mutations in human cancers and is typically associated with a poor prognosis. However, there are conflicting findings regarding its impact. We aimed to clarify the clinical relevance of mutations across all breast cancer subtypes and treatments utilizing long-term follow-up data.
View Article and Find Full Text PDFThis study explores differences in immune cell (IC) composition and spatial distribution between triple-negative breast cancer (TNBC) and hormone receptor-positive, HER2-negative breast cancer (HR + HER2-BC) in high-TIL (≥60%) cases, focusing on PD-L1 status. Using multiplex immunofluorescence on resected tumor tissues from 18 TNBC and 14 HR + HER2-BC cases, we analyzed IC types (CD20, CD8, CD4, FOXP3) and their spatial interactions. TNBC showed a unique IC composition characterized by a higher proportion of CD8 + IC (stroma: 27% vs 17%, p < 0.
View Article and Find Full Text PDFArticle Synopsis
- Young patients under 45 with ER-positive, ERBB2-negative breast cancer experience poor outcomes, with a focus on understanding factors that lead to late recurrence.
- This study aimed to see if age affects the chances of late distant recurrence (DR) in patients who had no previous metastasis within 5 years post-surgery.
- Out of 2772 patients analyzed, those aged 21-35 exhibited worse tumor grades and higher chemotherapy usage compared to older groups, indicating they may have a higher risk of late DR.
Background: HER2-positivity is an essential marker for therapeutic decisions, while HER2 expression is heterogenous. In recent years, there has been increasing recognition of a subgroup of breast cancer patients who have low levels of HER2 expression, also known as HER2-low because trastuzumab deruxtecan offers clinical benefit for patients with HER2-low metastatic breast cancer. Despite the growing interest in HER2-low breast cancer, there is limited research on how multigene assays can help differentiate between HER2-low and HER2-negative breast cancer.
View Article and Find Full Text PDFArticle Synopsis
- The study investigates the role of micrometastases in axillary lymph nodes after neoadjuvant systemic therapy (NST) in breast cancer patients, aiming to understand their impact on prognosis.
- Among 978 analyzed patients, 9.1% had micrometastases, showing a higher prevalence of additional metastases compared to those without node involvement.
- The findings suggest that while micrometastases do not affect recurrence-free survival, they are linked to worse outcomes, indicating that further axillary lymph node dissection may be necessary for affected patients.
Article Synopsis
- The study aimed to identify factors that differentiate between patients with limited brain metastases (1-4) and those with extensive metastases (5 or more) in breast cancer patients.
- Analyzed data from 100 women with brain metastases revealed that the status of de novo vs. recurrent metastatic disease significantly affects the extent of brain metastasis.
- The findings suggest that patients with newly diagnosed stage IV breast cancer are more likely to have extensive brain metastases, indicating a need for tailored monitoring and treatment strategies, especially through routine brain screenings.
Article Synopsis
- A previous study established a classification system for triple-negative breast cancer (TNBC) that aligns with molecular subtypes.
- The current study aims to validate this classification by assessing predictor variables and genomic alterations using an external test dataset.
- The classification divides TNBC into luminal androgen receptor (LAR) and non-LAR subtypes, with further stratification of non-LAR into lymphocyte-related groups, revealing distinct genomic characteristics for each subtype.
Article Synopsis
- The ASLAN trial aims to assess the safety of skipping axillary surgery in patients with HER2-positive or triple-negative breast cancer who have responded well to neoadjuvant chemotherapy after undergoing breast-conserving surgery and radiation.
- The study will recruit 178 patients from five hospitals in South Korea, with the goal of completing enrollment by December 2023 and focusing on patients expected to achieve breast pathological complete response after treatment.
- The trial's main goal is to evaluate 5-year recurrence-free survival, along with various secondary outcomes related to breast cancer recurrence and patient quality of life.
Article Synopsis
- The study assessed the feasibility of sentinel lymph node biopsy (SLNB) after neoadjuvant systemic therapy (NAST) in breast cancer patients with high nodal involvement.
- A total of 388 patients were analyzed, and outcomes were compared based on MRI responses and cancer subtypes, specifically focusing on hormone receptor-positive HER2- and HER2+/triple-negative breast cancers (TNBC).
- Results indicated that SLNB is reliable for evaluating nodal status in patients with complete MRI responses, particularly among HER2+ and TNBC patients, with notably low false-negative rates.
Article Synopsis
- The study investigated the clinical importance of tumor stiffness in breast cancer and its relationship with tumor-infiltrating lymphocyte (TIL) levels using shear-wave elastography (SWE), examining 803 patients from January 2016 to August 2020.
- Results showed that higher tumor stiffness was linked to larger tumor size and more advanced disease stages, but negatively associated with TIL levels, especially in hormone receptor-positive and HER2-negative subtypes.
- The findings suggest that tumor stiffness has different clinical meanings depending on the breast cancer type, with increased stiffness indicating more aggressive behavior primarily in hormone receptor-positive and HER2-negative tumors, while high TIL levels are associated with lower stiffness across all subtypes.
Article Synopsis
- Sentinel lymph node biopsy (SLNB) is commonly recommended for patients with ductal carcinoma in situ (DCIS) who undergo mastectomy, although it may lead to unnecessary treatments due to favorable prognosis and changing management trends in DCIS.
- A study reviewed 385 DCIS patients to evaluate the rates of invasive carcinoma upgrades and axillary lymph node metastasis, finding that 42.6% experienced upgrades and only 4.4% had metastasis.
- Factors such as being 50 years old or younger and having suspicious axillary lymph nodes were associated with higher rates of metastasis, indicating that SLNB might be safely omitted in older patients or those without suspicious lymph nodes.
Article Synopsis
- The study investigates clinical factors linked to breast cancer (BRCA) dural metastases (DMs) and compares their outcomes to brain parenchymal metastases (BPMs).
- It analyzes data from 119 patients, revealing that DMs are associated with extracranial metastases and specific breast cancer subtypes, but do not significantly impact overall survival compared to BPMs.
- The findings highlight differences in characteristics and prognosis among DM subtypes, particularly noting the relationship between nodular and diffuse DM types with various cancer indicators.
Article Synopsis
- The study evaluates whether patients who are predicted to have a pathologic complete response (pCR) after neoadjuvant systemic therapy (NST) for breast cancer can safely skip surgery, using MRI and vacuum-assisted biopsy (VAB) as diagnostic tools.
- It involves a multicenter trial across 17 hospitals in South Korea, focusing on patients who meet specific criteria, including having a clip marker in the tumor and favorable MRI results post-NST.
- The research aims to potentially change clinical practices by demonstrating that omitting surgery could lead to a similar 5-year disease-free survival rate, ultimately enhancing the quality of life for patients who respond exceptionally well to treatment.
Article Synopsis
- - In a study of 348 patients with HER2-positive breast cancer treated with neoadjuvant therapy (TCHP), about 80% showed a positive HER2 immunochemistry (IHC) status, and a significant percentage had high levels of tumor-infiltrating lymphocytes (TIL).
- - Factors like estrogen receptor (ER) status, HER2 expression level, and TIL levels were found to significantly influence the rate of pathologic complete response (pCR) after treatment.
- - The study concluded that ER and HER2 expression, and TIL levels are key predictors of how well patients respond to treatment, with ER-negative cases showing particularly strong responses regardless of other factors.
Article Synopsis
- The study focused on creating a machine learning model to predict risk categories for multi-gene assays (MGA) in patients with estrogen receptor-positive (ER+)/HER2- breast cancer, using data from Oncotype DX (ODX) and MammaPrint (MMP).
- It utilized various machine learning techniques, including XGBoost and soft voting among multiple models, achieving high accuracy rates of 84.8% for MMP, 87.9% for ODX, and 86.8% for the combined ensemble model.
- The model showed particularly high predictive accuracy, reaching 95.7% in certain subgroups, suggesting its potential to enhance existing testing methods for risk assessment in this type of breast
Article Synopsis
- Shear-wave elastography (SWE) is a useful method for identifying malignant breast lesions and lymph node metastasis in breast cancer patients, but its relationship with chemotherapy response is still unclear.
- In a study of 830 patients undergoing neoadjuvant chemotherapy, those with lower baseline stiffness values (E-mean and E-max) showed significantly higher rates of pathological complete response (pCR) to treatment.
- The findings suggest that low elasticity values from SWE could be independent predictors of treatment success and are associated with high tumor-infiltrating lymphocytes (TILs), particularly in hormone receptor-positive HER2-negative and triple-negative breast cancers.
Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with inferior outcomes owing to its low treatment response and high invasiveness. Based on abundant cancer-associated fibroblasts (CAFs) and frequent mutation of breast cancer-associated 1 (BRCA1) in TNBC, the characteristics of CAFs in TNBC patients with BRCA1 mutation compared to wild-type were investigated using single-cell analysis. Intriguingly, we observed that characteristics of inflammatory CAFs (iCAFs) were enriched in patients with BRCA1 mutation compared to the wild-type.
View Article and Find Full Text PDFArticle Synopsis
- * Analyzing data from 401 patients, researchers found that higher YAP1 expression was associated with lower risk scores and better clinical outcomes, especially in estrogen receptor-positive patients.
- * The findings suggest that YAP1 could serve as a promising prognostic marker and a potential target for therapy in this specific group of breast cancer patients.
We investigated a prognostic impact of radiotherapy-induced lymphopenia (RIL) in breast cancer patients treated with breast-conservative surgery (BCS). We included 531 breast cancer patients who were treated with BCS and adjuvant radiotherapy. None of these received (neo)adjuvant chemotherapy.
View Article and Find Full Text PDF