Concurrent Versus Sequential Adjuvant Capecitabine-Based Chemoradiation in Residual Triple-Negative Breast Cancer After Neoadjuvant-Chemotherapy: A Multicenter Comparative Study.

Purpose: Given the aggressive nature and poor prognosis of triple-negative breast cancer (TNBC), adjuvant capecitabine has been the standard therapy for residual disease after preoperative systemic therapy (PST). However, the optimal sequence of postoperative radiation therapy (RT) and capecitabine remains unclear. This study evaluated the efficacy and safety of concurrent RT and capecitabine (RT+CAP) versus sequential RT followed by capecitabine (RT→CAP) in patients with residual TNBC after PST.

Impact of the ASTRO 2024 Guideline on Partial Breast Irradiation Eligibility in Breast Cancer Patients (KROG 24-01).

Purpose: The American Society for Radiation Oncology (ASTRO) has recently published new guidelines for the eligibility for partial breast irradiation (PBI). This study aims to evaluate the eligibility rates of PBI according to the ASTRO 2017 and 2024 guidelines.

Methods And Materials: Patients diagnosed with pTis-T2N0 breast cancer in 2019 from 3 tertiary medical centers were accrued.

Treatment Outcomes after Postoperative Radiotherapy in Triple-Negative Breast Cancer: Multi-Institutional Retrospective Study (KROG 17-05).

Background: We designed a multi-institutional retrospective study to investigate the previously unreported failure pattern, survivals, and prognostic factors after postoperative radiotherapy (PORT) in triple negative breast cancer (TNBC) patients in South Korea.

Materials And Methods: We retrospectively reviewed 699 patients with TNBC who underwent PORT at six institutions between 2008 and 2010. The median follow-up period was 94 months (range: 7-192 months).

Risk of radionecrosis in HER2-positive breast cancer with brain metastasis receiving trastuzumab emtansine (T-DM1) and brain stereotactic radiosurgery.

Objectives: To investigate the potential relationship between trastuzumab emtansine (T-DM1) treatment and radionecrosis induced by brain stereotactic radiosurgery (SRS) in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer.

Materials And Methods: Patients with HER2-positive breast cancer who were diagnosed with brain metastasis and received both SRS and HER2-targeted agents between 2012 and 2022 were retrospectively analyzed. Patients who received T-DM1 within 1 year (either before or after) of SRS were considered as 'T-DM1 exposure (+)'.

Evaluation of cosmetic outcomes in breast reconstruction patients undergoing radiotherapy using an anomaly generative adversarial network model.

Considering the rising prevalence of breast reconstruction followed by radiotherapy (RT), evaluating the cosmetic impact of RT is crucial. Currently, there are limited tools for objectively assessing cosmetic outcomes in patients who have undergone reconstruction. Therefore, we validated the cosmetic outcome using a previously developed anomaly Generative Adversarial Network (GAN)-based model and evaluated its utility.

The impact of the new ESTRO-ACROP target volume delineation guidelines for postmastectomy radiotherapy after implant-based breast reconstruction on breast complications.

The European Society for Radiotherapy and Oncology-Advisory Committee in Radiation Oncology Practice (ESTRO-ACROP) updated a new target volume delineation guideline for postmastectomy radiotherapy (PMRT) after implant-based reconstruction. This study aimed to evaluate the impact on breast complications with the new guideline compared to the conventional guidelines. In total, 308 patients who underwent PMRT after tissue expander or permanent implant insertion from 2016 to 2021 were included; 184 received PMRT by the new ESTRO-ACROP target delineation (ESTRO-T), and 124 by conventional target delineation (CONV-T).

Assessment of lymph node area coverage with total marrow irradiation and implementation of total marrow and lymphoid irradiation using automated deep learning-based segmentation.

Background: Total marrow irradiation (TMI) and total marrow and lymphoid irradiation (TMLI) have the advantages. However, delineating target lesions according to TMI and TMLI plans is labor-intensive and time-consuming. In addition, although the delineation of target lesions between TMI and TMLI differs, the clinical distinction is not clear, and the lymph node (LN) area coverage during TMI remains uncertain.

Estimating the risk and benefit of radiation therapy in (y)pN1 stage breast cancer patients: A Bayesian network model incorporating expert knowledge (KROG 22-13).

Background: We aimed to evaluate the risk and benefit of (y)pN1 breast cancer patients in a Bayesian network model.

Method: We developed a Bayesian network (BN) model comprising three parts: pretreatment, intervention, and risk/benefit. The pretreatment part consisted of clinical information from a tertiary medical center.

Assessment of Eligibility and Utilization of Accelerated Partial Breast Irradiation in Korean Breast Cancer Patients (KROG 22-15).

Purpose: We investigated the proportions of patients eligible for accelerated partial breast irradiation (APBI) among those with pT1-2N0 breast cancer, based on the criteria set by the American Society for Radiation Oncology (ASTRO), the Groupe Européen de Curiethérapie and the European Society for Radiotherapy and Oncology (GEC-ESTRO), the American Brachytherapy Society (ABS), and the American Society of Breast Surgeons (ASBS). Additionally, we analyzed the rate of APBI utilization among eligible patients.

Materials And Methods: Patients diagnosed with pT1-2N0 breast cancer in 2019 were accrued in four tertiary medical centers in Korea.

Assessment of deep learning-based auto-contouring on interobserver consistency in target volume and organs-at-risk delineation for breast cancer: Implications for RTQA program in a multi-institutional study.

Purpose: To quantify interobserver variation (IOV) in target volume and organs-at-risk (OAR) contouring across 31 institutions in breast cancer cases and to explore the clinical utility of deep learning (DL)-based auto-contouring in reducing potential IOV.

Methods And Materials: In phase 1, two breast cancer cases were randomly selected and distributed to multiple institutions for contouring six clinical target volumes (CTVs) and eight OAR. In Phase 2, auto-contour sets were generated using a previously published DL Breast segmentation model and were made available for all participants.

Developing prompts from large language model for extracting clinical information from pathology and ultrasound reports in breast cancer.

Purpose: We aimed to evaluate the time and cost of developing prompts using large language model (LLM), tailored to extract clinical factors in breast cancer patients and their accuracy.

Materials And Methods: We collected data from reports of surgical pathology and ultrasound from breast cancer patients who underwent radiotherapy from 2020 to 2022. We extracted the information using the Generative Pre-trained Transformer (GPT) for Sheets and Docs extension plugin and termed this the "LLM" method.

Concurrent Lapatinib With Brain Radiation Therapy in Patients With HER2+ Breast Cancer With Brain Metastases: NRG Oncology-KROG/RTOG 1119 Phase 2 Randomized Trial.

Purpose: Lapatinib plus whole brain radiation therapy (WBRT) or stereotactic radiosurgery (SRS) was hypothesized to improve the 12-week intracranial complete response (CR) rate compared with either option of radiation therapy (RT) alone for patients with brain metastases (BM) from human epidermal growth factor receptor 2-positive (HER2+) breast cancer.

Methods And Materials: This study included patients with HER2+ breast cancer with ≥1 measurable, unirradiated BM. Patients were randomized to WBRT (37.

A Survey of Practice Patterns for Clinical Nodal Staging Prior to Neoadjuvant Chemotherapy in Breast Cancer.

Background: The importance of clinical staging in breast cancer has increased owing to the wide use of neoadjuvant systemic therapy (NST). This study aimed to investigate the current practice patterns regarding clinical nodal staging in breast cancer in real-world settings.

Materials And Methods: A web-based survey was administered to board-certified oncologists in Korea, including breast surgical, medical, and radiation oncologists, from January to April 2022.

Patterns and Longitudinal Changes in the Practice of Breast Cancer Radiotherapy in Korea: Korean Radiation Oncology Group 22-01.

Purpose: We aimed to analyze contemporary practice patterns in breast cancer radiotherapy (RT) and assess longitudinal changes over five years in Korea.

Methods: In 2022, a nationwide survey was conducted among board-certified radiation oncologists. The survey consisted of 44 questions related to six domains: hypofractionated (HypoFx) whole breast RT, accelerated partial breast RT (APBI), regional nodal irradiation (RNI), RT for ductal carcinoma (DCIS), postmastectomy RT (PMRT), and tumor bed boost.

Evaluation of initial patient setup methods for breast cancer between surface-guided radiation therapy and laser alignment based on skin marking in the Halcyon system.

Background: This study was conducted to evaluate the efficiency and accuracy of the daily patient setup for breast cancer patients by applying surface-guided radiation therapy (SGRT) using the Halcyon system instead of conventional laser alignment based on the skin marking method.

Methods And Materials: We retrospectively investigated 228 treatment fractions using two different initial patient setup methods. The accuracy of the residual rotational error of the SGRT system was evaluated by using an in-house breast phantom.

Omission of axillary lymph node dissection in patients with ypN+ breast cancer after neoadjuvant chemotherapy: A retrospective multicenter study (KROG 21-06).

Background: We evaluated the impact of omitting axillary lymph node dissection (ALND) on oncological outcomes in breast cancer patients with residual nodal disease after neoadjuvant chemotherapy (NAC).

Methods: The medical records of patients who underwent NAC followed by surgical resection and had residual nodal disease were retrospectively reviewed. In total, 1273 patients from 12 institutions were included; all underwent postoperative radiotherapy.

Prediction of breast cancer-related lymphedema risk after postoperative radiotherapy multivariable logistic regression analysis.

Purpose: We identified novel clinical and dosimetric prognostic factors affecting breast cancer-related lymphedema after postoperative radiotherapy (RT) and developed a multivariable logistic regression model to predict lymphedema in these patients.

Methods And Materials: In total, 580 patients with unilateral breast cancer were retrospectively reviewed. All patients underwent breast surgery and postoperative RT with or without systemic treatment in 2015.

Protocol for the postoperative radiotherapy in N1 breast cancer patients (PORT-N1) trial, a prospective multicenter, randomized, controlled, non-inferiority trial of patients receiving breast-conserving surgery or mastectomy.

Background: Postoperative radiotherapy (PORT) could be useful for pN1 breast cancer patients who have undergone breast-conserving surgery (BCS) or mastectomy. However, the value of regional nodal irradiation (RNI) for BCS patients, and the indications for post-mastectomy radiotherapy (PMRT) for pN1 breast cancer mastectomy patients, have recently been challenged due to the absence of relevant trials in the era of modern systemic therapy. "PORT de-escalation" should be assessed in patients with pN1 breast cancer.

Intensity Modulated Radiotherapy and Volumetric Modulated Arc Therapy in the Treatment of Breast Cancer: An Updated Review.

Radiation therapy (RT) plays a critical role in breast cancer treatment. In the modern technological era, innovations and progress in breast RT and delivery techniques have greatly improved the clinical outcomes. Intensity-modulated RT (IMRT) is a modern RT technology that permits the modulation of RT beams, ensuring a more uniform dose distribution through the target tissue and better avoidance of underlying critical structures.