Randomized, phase II trial to evaluate the efficacy and safety of atezolizumab plus capecitabine adjuvant therapy compared to capecitabine monotherapy for triple receptor-negative breast cancer with residual invasive cancer after neoadjuvant chemotherapy (MIRINAE trial, KCSG-BR18-21).

Triple-negative breast cancer (TNBC) is an aggressive subtype with poor prognosis, especially in patients with residual disease post-neoadjuvant chemotherapy. This phase II MIRINAE trial (KCSG-BR18-21) evaluates the efficacy and safety of atezolizumab combined with capecitabine versus capecitabine monotherapy as adjuvant treatment in TNBC patients with residual invasive cancer. The primary endpoint is the 5-year invasive disease-free survival (IDFS) rate.

Prevalence of germline pathogenic variants in unselected Korean patients with HER2-negative metastatic breast cancer: a nationwide prospective study (KCSG BR19-10).

Background: Assessment of germline (g) status is recommended for all patients with HER2-negative metastatic breast cancer (MBC) to identify candidates for poly(ADP-ribose) polymerase (PARP) inhibitor therapy, which is not always possible in clinical practice due to limited testing resources. In this study, we investigate the cross-sectional prevalence of g pathogenic variant (PV) carriers in unselected Korean patients with HER2-negative MBC.

Methods: Patients diagnosed with HER2-negative metastatic BC receiving palliative systemic treatment were eligible for inclusion in the study.

Nationwide real-world practice pattern and clinical data of palbociclib in HR (+), HER2 (-) metastatic breast cancer patients in Korea (KCSG BR21-15).

Background: Cyclin-dependent kinase (CDK) 4/6 inhibitors have remarkably improved the survival outcome in hormone-receptor-positive (HR+)/human epidermal growth factor-2-negative (HER2-) metastatic breast cancer (mBC). Although PALOMA-2 has met its primary outcome, overall survival (OS) was relatively shorter compared to ribociclib and abemaciclib. In Korea, use of palbociclib + aromatase inhibitor (AI) + gonadotropin-releasing hormone agonist (GnRHa) in premenopausal women is limited, and bilateral salpingo-oophorectomy (BSO) is necessary before treatment.

Spatial Transcriptomic Landscape of Brain Metastases from Triple-Negative Breast Cancer: Comparison of Primary Tumor and Brain Metastases Using Spatial Analysis.

Purpose: Triple-negative breast cancer (TNBC) is a particularly aggressive subtype of breast cancer, with approximately 30% of patients eventually developing brain metastases (BM), which result in poor outcomes. An understanding of the tumor microenvironment (TME) at both primary and metastatic sites offers insights into the mechanisms underlying BM and potential therapeutic targets.

Materials And Method: Spatial RNA sequencing (spRNA-seq) was performed on primary TNBC and paired BM tissues from three patients, one of whom had previously received immune checkpoint inhibitors before BM diagnosis.

Clinical relevance of clinical treatment score post-5 years (CTS5) in HR-positive, HER2-positive breast cancer.

There is currently no reliable predictive tool for late recurrence in hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-positive breast cancer. This study aimed to explore the potential of the clinical treatment score post-5l̥years (CTS5) as a predictive tool for long-term survival beyond 5 years in patients with specifically HR-positive, HER2-positive breast cancer. We collected patient-level data from the HERceptin Adjuvant (HERA) (BIG1-01; ClinicalTrials.

Stromal tumor-infiltrating lymphocytes and pathologic response to neoadjuvant chemotherapy with the addition of platinum and pembrolizumab in TNBC: a single-center real-world study.

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.

Adjuvant Trastuzumab Plus Pertuzumab Versus Trastuzumab Alone in Patients Achieving Pathologic Complete Response After Chemotherapy With Trastuzumab and Pertuzumab: A Retrospective Cohort Study.

Background: For patients who achieve pathologic complete response (pCR) after neoadjuvant chemotherapy with trastuzumab (T) and pertuzumab (P), the benefit of adding P to T remains uncertain. We compared survival outcomes according to the type of adjuvant anti-HER2 therapy in patients with pCR after chemotherapy with TP.

Method: Patients who achieved pCR in both the breast and axilla after neoadjuvant chemotherapy with TP were included.

Immune environment of high-TIL breast cancer: triple negative and hormone receptor positive HER2 negative.

This 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.

Feasibility of Intraoperative Radiotherapy Tumor Bed Boost in Patients with Breast Cancer after Neoadjuvant Chemotherapy.

Purpose: This study aimed to assess the feasibility and safety of administering intraoperative radiotherapy (IORT) as a boost during breast-conserving surgery (BCS) following neoadjuvant chemotherapy for patients at high risk of breast cancer recurrence.

Materials And Methods: Patients who underwent neoadjuvant chemotherapy received a single 20-Gy dose of IORT during BCS, followed by external beam radiotherapy 4-6 weeks after surgery.

Results: The median follow-up duration was 31.

Copy number aberrations in circulating tumor DNA enables prognosis prediction and molecular characterization of breast cancer.

Background: Low-pass whole-genome sequencing (LP-WGS)-based circulating tumor DNA (ctDNA) analysis is a versatile tool for somatic copy number aberration (CNA) detection, and this study aims to explore its clinical implication in breast cancer.

Methods: We analyzed LP-WGS ctDNA data from 207 metastatic breast cancer (MBC) patients to explore prognostic value of ctDNA CNA burden and validated it in 465 stage II-III triple-negative breast cancer (TNBC) patients who received neoadjuvant chemotherapy in phase III PEARLY trial (NCT02441933). The clinical implication of locus level LP-WGS ctDNA profiling was further evaluated.

Efficacy of Limited Dose Modifications for Palbociclib-Related Grade 3 Neutropenia in Hormone Receptor-Positive Metastatic Breast Cancer.

Purpose: Frequent neutropenia hinders uninterrupted palbociclib treatment in patients with hormone receptor (HR)-positive breast cancer. We compared the efficacy outcomes in multicenter cohorts of patients with metastatic breast cancer (mBC) receiving palbociclib following conventional dose modification or limited modified schemes for afebrile grade 3 neutropenia.

Materials And Methods: Patients with HR-positive, human epidermal growth factor receptor 2-negative mBC (n=434) receiving palbociclib with letrozole as first-line therapy were analyzed and classified based on neutropenia grade and afebrile grade 3 neutropenia management as follows: group 1 (maintained palbociclib dose, limited scheme), group 2 (dose delay or reduction, conventional scheme), group 3 (no afebrile grade 3 neutropenia event), and group 4 (grade 4 neutropenia event).

Resolution of Nonmass Enhancement Extension to the Nipple at Breast MRI after Neoadjuvant Chemotherapy: Pathologic Response and Feasibility for Nipple-sparing Mastectomy.

Background Nipple-sparing mastectomy (NSM) is usually contraindicated in patients with nonmass enhancement (NME) extension to the nipple at breast MRI. However, little is known about the feasibility of NSM when NME extension to the nipple resolves after neoadjuvant chemotherapy (NAC). Purpose To evaluate whether NSM is an appropriate surgical procedure for patients in whom NME extension to the nipple resolves after NAC.

On-treatment derived neutrophil-to-lymphocyte ratio and survival with palbociclib and endocrine treatment: analysis of a multicenter retrospective cohort and the PALOMA-2/3 study with immune correlates.

Background: Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors have been established as a standard treatment for hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC); however, predictive biomarkers with translational relevance have not yet been elucidated.

Methods: Data from postmenopausal women who received the CDK4/6 inhibitor palbociclib and letrozole for HR-positive, HER2-negative ABC from tertiary referral centers were analyzed (N = 221; exploratory cohort). Pre- and on-treatment neutrophil-to-lymphocyte ratio (NLR) and derived NLR (dNLR; neutrophil/[leukocyte-neutrophil]) were correlated with survival outcomes.

Hyperprogressive disease during PD-1 blockade in patients with advanced gastric cancer.

Background: Investigations for programmed cell death-1 (PD-1) blockade-induced hyperprogressive disease (HPD) have not been stringently conducted in patients with advanced gastric cancer (AGC). We explored the occurrence of HPD and its clinical implications in patients with AGC and treated with PD-1 inhibitors.

Methods: We enrolled 169 patients with AGC and treated with either the PD-1 blockade (nivolumab or pembrolizumab; N = 112) or irinotecan monotherapy (N = 57) as a single agent.