Antiamoebic activities of flavonoids against pathogenic free-living amoebae, Naegleria fowleri and Acanthamoeba species.

Free-living amoebae (FLA) rarely cause human infections but can invoke fatal infections in the central nervous system (CNS). No consensus treatment has been established for FLA infections of the CNS, emphasizing the urgent need to discover or develop safe and effective drugs. Flavonoids, natural compounds from plants and plant-derived products, are known to have antiprotozoan activities against several pathogenic protozoa parasites. The anti-FLA activity of flavonoids has also been proposed, while their antiamoebic activity for FLA needs to be emperically determined. We herein evaluated the antiamoebic activities of 18 flavonoids against Naegleria fowleri and Acanthamoeba species which included A. castellanii and A. polyphaga. These flavonoids showed different profiles of antiamoebic activity against N. fowleri and Acanthamoeba species. Demethoxycurcumin, kaempferol, resveratrol, and silybin (A+B) showed in vitro antiamoebic activity against both N. fowleri and Acanthamoeba species. Apigenin, costunolide, (‒)-epicatechin, (‒)-epigallocatechin, rosmarinic acid, and (‒)-trans-caryophyllene showed selective antiamoebic activity for Acanthamoeba species. Luteolin was more effective for N. fowleri. However, afzelin, berberine, (±)-catechin, chelerythrine, genistein, (+)-pinostrobin, and quercetin did not exhibit antiamoebic activity against the amoeba species. They neither showed selective antiamoebic activity with significant cytotoxicity to C6 glial cells. Our results provide a basis for the anti-FLA activity of flavonoids, which can be applied to develope alternative or supplemental therapeutic agents for FLA infections of the CNS.

Sports Value Consciousness Moderates the Effect of Exercise Behavior on Sport Activity Loyalty: A Moderated Mediation Model with Sports YouTube Engagement.

This study aims to address a lack of research on sports value consciousness among Korean university students by examining the moderated mediating effect of sports value consciousness on the relationship between university students' sports YouTube engagement and their sport activity loyalty. A total of 231 Korean university students were recruited for this study. The analytical model was validated using the SPSS PROCESS Macro (Model no. 8). Exercise behavior was found to have a significant positive effect on both sports YouTube engagement and sport activity loyalty, while sports YouTube engagement had a significant positive effect on sport activity loyalty. Furthermore, the interaction between exercise behavior and sports value consciousness had a significant positive effect on sport activity loyalty at a low to moderate level. Results suggest that, for Korean university students, sports value consciousness is more important at a low to moderate level of sport activity loyalty than at a high level. The importance of sports value consciousness is highlighted in the context of the development of sports media and the sociological aspects of sports engagement among university students.

Feasibility of partial-orbit irradiation as a treatment strategy for patients with orbital mucosa-associated lymphoid tissue lymphoma.

OBJECTIVE: For early-stage orbital mucosa-associated lymphoid tissue lymphoma (MALToma), radiotherapy (RT) is known to be the treatment of choice. The classical recommended treatment field is the entire ipsilateral orbit, exposing normal orbital structures such as the lacrimal gland and lens, which are sensitive to moderate doses of radiation, to the full treatment dose. Herein we aimed to evaluate the clinical outcomes and dosimetric values in patients with orbital MALToma who received RT. DESIGN: This study was a retrospective study. PARTICIPANTS: Forty patients with orbital MALToma treated with curative RT. METHODS: The patients were classified into the conjunctival RT (n = 23), partial-orbit RT (n = 10), and whole-orbit RT (n = 7) groups. The treatment outcomes and dosimetric values of the orbital structures were reviewed. RESULTS: We found the 5-year local, contralateral orbit, and overall relapse rates to be 5.0%, 5.9%, and 16.0%, respectively. Local relapse events occurred in 2 patients in the conjunctival RT group. No relapse was observed in the partial-orbit RT group. Whole-orbit RT caused significantly higher rates of dry eyes during treatment. The partial-orbit RT group showed a significantly lower ipsilateral eyeball mean dose and ipsilateral eyelid mean dose than the other groups. CONCLUSION: Partial-orbit RT showed encouraging clinical, toxicity, and dosimetric outcomes in patients with orbital MALToma and has the potential to be a treatment option for such patients.

Recent Trends in Continuum Modeling of Liquid Crystal Networks: A Mini-Review.

This work aims to provide a comprehensive review of the continuum models of the phase behaviors of liquid crystal networks (LCNs), novel materials with various engineering applications thanks to their unique composition of polymer and liquid crystal. Two distinct behaviors are primarily considered: soft elasticity and spontaneous deformation found in the material. First, we revisit these characteristic phase behaviors, followed by an introduction of various constitutive models with diverse techniques and fidelities in describing the phase behaviors. We also present finite element models that predict these behaviors, emphasizing the importance of such models in predicting the material's behavior. By disseminating various models essential to understanding the underlying physics of the behavior, we hope to help researchers and engineers harness the material's full potential. Finally, we discuss future research directions necessary to advance our understanding of LCNs further and enable more sophisticated and precise control of their properties. Overall, this review provides a comprehensive understanding of the state-of-the-art techniques and models used to analyze the behavior of LCNs and their potential for various engineering applications.

Team Cohesion in Individual/Team Sports Athletes: Transformational Leadership and the Role of Social norms.

Team cohesion is a critical factor in sports, yet few studies have comparatively analyzed individual and team sport athletes in sporting situations. The purpose of this study was to identify the relationship between transformational leadership, social norms, and team cohesion, and to analyze the moderating effects of individual/team sports athletes. In 2022, a total of 196 baseball, judo, soccer, taekwondo, and hockey players registered with the Korean Sport & Olympic Committee completed a questionnaire using transformational leadership, social norms, and team cohesion scales. Transformational leadership had a significant positive effect on social norms and team cohesion. Social norms had a significant positive effect on team cohesion. Transformational leadership and the interaction of individual/team sports athletes had a significant effect on team cohesion. At this time, individual sports athletes appeared to have somewhat higher team cohesion. This study sheds light on the social norms and team cohesion of athletes from a social moral perspective based on transformational leadership theory. It can also help young athletes who are just starting out to learn the culture and sociology of sports.

The Relationship between Exercise Re-Participation Intention Based on the Sports-Socialization Process: YouTube Sports Content Intervention.

Few studies have used a quantitative research methodology to examine the socialization process model, and such studies were conducted to verify a new model by intervening in the variables of YouTube sports content. To understand this process, we tested the moderated mediating effect by intervening in YouTube sports content based on the sports socialization process model. We recruited 274 participants from the Jeju Residents' Jeju Sports Festival, Korea. The PROCESS Macro program was performed to test the research hypotheses. The findings indicate that social support had a significant effect on re-participation intention. Social support had a significant mediation effect on exercise interruption intention, re-participation intention, and exercise performance satisfaction. Furthermore, through the relationship between social support and exercise interruption intention, YouTube sports content showed a significant interaction of re-participation intention in exercise. These results extend sports socialization theory by discovering a new model that explains the relationship between the sports socialization process and YouTube sports content. In addition, it will provide a basis for delivering educational information to the public so that they can recognize the importance of physical activity and exercise skills.

What is sport activity loyalty? Verifying the relationship between passion and psychological well-being.

BACKGROUND: The variables of sport activity loyalty are being utilized actively in the fields of sports management and marketing. This study seeks to understand sport activity loyalty and verify the causal relationship between passion and psychological well-being to discover a new convergent and comprehensive research model in the field of Kinesiology. METHODS: Passion, psychological well-being, and sport activity loyalty were measured for 198 college athletes who were registered as athletes in the 2021 Korean Sport & Olympic Committee (KSOC). To analyze the data, the SPSS 24.0, PROCESS Macro (V.2.13), and Amos 24.0 programs were used. RESULTS: First, harmonious passion had a significant positive effect on sport activity loyalty. Second, harmonious passion had a significant positive effect on psychological well-being, and obsessive passion had a significant positive effect on all variables of psychological well-being except self-realization. Third, the results of testing the mediating effect based on the direct effect revealed that harmonious and obsessive passion had significant indirect effects on sport activity loyalty through feelings of competence and hedonic enjoyment. CONCLUSIONS: It is hereby provided that we have examined the causal relationship between sport activity loyalty and sports psychology variables and discovered a new research model convergent between variables in the field of physical education (psychology-sociology, business administration).

Phragmites australis (Cav.) Trin. ex Steud. Extract Induces Apoptosis-like Programmed Cell Death in Acanthamoeba castellanii Trophozoites.

Acanthamoeba keratitis (AK) is an infectious ocular disease which is difficult to diagnose correctly and cure. Development of an effective and safe therapeutic drug for AK is needed. Our preliminary screening of more than 200 extracts from wild plants collected in Korea suggested the potential amoebicidal activity of Phragmites australis (Cav.) Trin. ex Steud. extract (PAE) against Acanthamoeba species. Here, we aimed to analyze the amoebicidal activity of PAE on Acanthamoeba and its underlying amoebicidal mechanism. PAE induced amoebicidal activity against both A. castellanii and A. polyphaga trophozoites, while it showed low cytotoxicity in human corneal epithelial cells (HCE-2) and human retinal pigment epithelial cells (ARPE-19). Transmission electron microscopy analysis showed subcellular morphological changes, such as increased granules, abnormal mitochondria, and atypical cyst wall formation, in the PAE-treated A. castellanii. Fluorometric apoptosis assay and TUNEL assay revealed apoptosis-like programmed cell death (PCD) in the PAE-treated A. castellanii. The PAE treatment increased reactive oxygen species production and reduced mitochondrial membrane potential in the amoeba. The enhanced expression of autophagy-associated genes was also detected. These results suggested that PAE exerted a promising amoebicidal effect on A. castellanii trophozoites via the PCD pathway. PAE could be a potential candidate for developing a therapeutic drug for AK.

The Effect of Coaching Types on Moral Disengagement in Taekwondo Athletes: The Mediating Role of Pride.

The purpose of this study was to examine how coaching styles affect athletes' moral disengagement. To achieve our objectives, we examined the relationships among perceived coaching types, pride, and moral disengagement in the context of elite taekwondo athletes (N = 322). Direct and indirect effects among coaching types, pride, and moral disengagement were assessed through path analysis. The results indicated that the autonomy-support coaching type reduced moral disengagement by decreasing hubristic pride, while the controlled coaching type increased moral disengagement through hubristic pride. Our study found a chain of effects according to the controlled coaching type perceived by taekwondo athletes, hubristic pride, and moral disengagement; therefore, the controlled coaching type and hubristic pride should be closely managed in sport society, as they elicit greater moral disengagement. Managerial strategies to diminish hubristic pride through the autonomy-support coaching type are recommended.

Analysis of thromboembolic events in head and neck cancer patients who underwent concurrent chemoradiotherapy with cisplatin.

BACKGROUND/AIMS: The study investigated the incidence of thromboembolic events (TEE) in head and neck (H&N) cancer patients who received concurrent chemoradiotherapy (CCRT) with cisplatin, and analyzed the factors affecting TEE occurrence. METHODS: Two hundred and fifty-seven patients who started CCRT with cisplatin for H&N cancer from January 2005 to December 2019 were analyzed. RESULTS: TEE occurred in five patients, an incidence rate of 1.9%. The 2-, 4-, and 6-month cumulative incidences of TEE were 0.8%, 1.6%, and 1.9%, respectively. Khorana score was the only factor associated with TEE occurrence (p = 0.010). CONCLUSION: The incidence of TEE in H&N cancer patients who underwent CCRT with cisplatin was relatively low when compared to other types of cancer. However, patients with a high Khorana score require more careful surveillance for possible TEE occurrence.

Verification of causal relationships between passion, social behavior and the exercise dependence of athletes.

BACKGROUND: Factors strengthening exercise dependence are found in the temperamental disposition of athletes and environmental variables. We aim to understand the antecedents that engender exercise dependence and unearth the environmental variables that can control exercise-dependent symptoms. The purpose of this study is to verify causal relationships between passion, social behavior and exercise dependence. METHODS: Passion, social behavior and exercise dependence of 216 university athletes registered as players with the Korean Sports & Olympic Committee as of 2021 were measured. SPSS 24.0, PROCESS Macro (V.2.13), and Amos 24.0 programs were used for data analysis. RESULTS: First, passion (harmonious, obsessive) had a significantly positive effect on social behavior (prosocial and antisocial behavior). Second, antisocial behavior had a significantly positive effect on the subfactors of exercise dependence such as tolerance, withdrawal, time, reduction in other activities, and continuance. Third, as a result of verifying the mediating effects based on direct effects, harmonious passion had significant indirect effects on all factors, except tolerance, by mediating antisocial behavior, and obsessive passion had significant indirect effects on all variables, except intention effects and lack of control, by mediating antisocial behavior. CONCLUSIONS: We discovered implications on a new variable in the relationship between passion and exercise dependence. In the future, sport-psychology sociologists must continuously seek variables that can control this.

Mediating effect of social behavior on passion and aggression of Taekwondo athletes: validation of three instruments in the Korean language.

BACKGROUND: Researchers have reported a close relationship between the passion and aggression among athletes. However, studies that verify their causal relationship in terms of social behavior are insufficient. This study was conducted to test the causal relationship between the passion, social behavior, and aggression of Taekwondo athletes. METHODS: The study recruited 193 Taekwondo athletes in Korea and Passion, social behavior, and aggression composed of Korean language were measured. The SPSS 23.0, PROCESS Macro (V.2.13), and Amos 23.0 were used for data analysis. RESULTS: First, the harmonious passion exerted significant positive and negative effects on the prosocial and antisocial behaviors, respectively. Moreover, obsessive passion exerted a significant positive effect on antisocial behavior. Second, the prosocial behavior exerted a significant negative effect on anger, whereas the antisocial behavior had a significant positive effect on anger and aggressiveness. Third, upon examining the mediating effect based on the direct effect, the harmonious passion exerted a partially, significantly negative indirect effect on anger and aggressiveness with the social behavior as the mediator. Lastly, the obsessive passion exerted a partially, significantly positive indirect effect on anger and aggressiveness with the social behavior as the mediator. CONCLUSIONS: This study verified the causal relationship between aggressions through the social behavior and derived a very meaningful result from the sports psychology and sociological aspect in that it expanded the theoretical scope and discovered a new research model. This finding suggests that the study can contribute to understand the social behavior of humans and the development of physical education.

The efficacy of EGFR-tyrosine kinase inhibitor in non-small cell lung cancer patients with synchronous brain metastasis: a real-world study.

BACKGROUND/AIMS: The optimal treatment (Tx) for epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients with brain metastasis (BM) remains to be determined. METHODS: A retrospective review was conducted on 77 NSCLC patients with synchronous BM who underwent first-line EGFR-tyrosine kinase inhibitor (TKI) Tx. The outcomes of patients were analyzed according to the clinicopathological characteristics including local Tx modalities. RESULTS: Fifty-nine patients underwent local Tx for BM (gamma knife surgery [GKS], 37; whole brain radiotherapy [WBRT], 18; others, four) concurrently or sequentially with EGFR-TKI. Patients treated with TKI alone showed significantly lower incidence of central nervous system (CNS) symptoms. The median progression-free survival (PFS) and overall survival (OS) after the initiation of EGFR-TKI for all patients were 9 and 19 months, respectively. In 60 patients with follow-up brain imaging, the median time to CNS progression was 15 months. Patients with EGFR exon 19 deletion had a significantly longer median OS than those with other mutations including L858R (23 months vs. 17 months). Other clinical characteristics, including CNS symptoms, number of BM, and the use of local Tx were not associated with OS, as well as PFS. In terms of the local optimal Tx modality, no difference was found between GKS and WBRT in the OS and PFS. CONCLUSION: This study suggests that EGFR-TKI may result in a favorable outcome in NSCLC patients with synchronous BM, especially in deletion 19 mutant, regardless of the extent of BM lesions or local Tx modalities. Patients with asymptomatic BM can be treated with EGFR-TKI and careful surveillance.

Relationship between passion and psychological well-being of taekwondo athletes: testing the mediating effects of social behavior.

BACKGROUND: The study uses PROCESS Macro statistical model and examines the causal relationship of passion, social behavior, and psychological well-being of taekwondo athletes. METHODS: Passion, social behavior, and psychological well-being were measured among 261 registered athletes at Korea Taekwondo Association in 2021 in South Korea. The collected data was analyzed using SPSS 24.0 (SPSS Inc., Chicago, IL, USA), PROCESS Macro (Calgary, AB, Canada), Amos 24.0 (IBM Corp, Armonk, NY, USA). RESULTS: Harmonious passion had a significant indirect effect through prosocial behavior on the feelings of self-realization, confidence, and flow and through antisocial behavior on the feeling of flow. Obsessive passion had a significant indirect effect through prosocial behavior on the feelings of self-realization, confidence, and flow and through antisocial behavior on feeling of flow, hedonic enjoyment. CONCLUSIONS: The results of the study suggest that the level of perceiving psychological well-being differs based on the level of taekwondo athletes' dualistic passion. social behavior, the study is expected to serve as a model study that enables applying psychological well-being.

Survey of radiation field and dose in human papillomavirus-positive oropharyngeal cancer: is de-escalation actually applied in clinical practice?

PURPOSE: Studies on de-escalation in radiation therapy (RT) for human papillomavirus-related (HPV(+)) oropharyngeal cancer (OPC) are currently ongoing. This study investigated the current practice regarding the radiation dose and field in the treatment of HPV(+) OPC. MATERIALS AND METHODS: The Korean Society for Head and Neck Oncology conducted a questionnaire on the primary treatment policy. Among them, for HPV(+) OPC scenarios, radiation oncologists were questioned regarding the field and dose of RT. RESULTS: Forty-two radiation oncologists responded to the survey. In definitive concurrent chemoradiotherapy (CCRT) treatment for stage T2N1M0 OPC, most respondents prescribed a dose of >60 Gy to the primary tonsil and involved ipsilateral lymph nodes. However, eight of the respondents prescribed a relatively low dose of ≤54 Gy. For stage T2N1M0 OPC, postoperative adjuvant RT was prescribed by eight and nine respondents with a lower dose of ≤50 Gy for the ipsilateral tonsil and involved neck, respectively. In definitive CCRT in complete remission after induction chemotherapy for initial stage T2N3M0 OPC, de-escalation of the tonsil and involved neck were performed by eight and seven respondents, respectively. Regarding whether de-escalation is applied in radiotherapy for HPV(+) OPC, 27 (64.3%) did not do it at present, and 15 (35.7%) were doing or considering it. CONCLUSION: The field and dose of prescribed treatment varied between institutions in Korea. Among them, dose de-escalation of RT in HPV(+) OPC was observed in approximately 20% of the respondents. Consensus guidelines will be set in the near future after the completion of ongoing prospective trials.

Whole-Brain Radiotherapy vs. Localized Radiotherapy after Resection of Brain Metastases in the Era of Targeted Therapy: A Retrospective Study.

Whether targeted therapy (TT) and radiotherapy impact survival after resection of brain metastases (BM) is unknown. The purpose of this study was to analyze the factors affecting overall survival (OS), local control (LC), distant control (DC), and leptomeningeal metastases (LMM) in patients who had undergone resection of BM. We retrospectively analyzed 124 consecutive patients who had undergone resection of BM between 2004 and 2020. Patient information about age, sex, Karnofsky Performance Scale (KPS), origin of cancer, synchronicity, tumor size, status of primary cancer, use of TT, extent of resection, and postoperative radiotherapy was collected. Radiation therapy was categorized into whole-brain radiotherapy (WBRT), localized radiotherapy (local brain radiotherapy or stereotactic radiosurgery (LBRT/SRS)), and no radiation. We identified factors that affect OS, LC, DC, and LMM. In multivariable analysis, significant factors for OS were higher KPS score (≥90) (HR 0.53, p = 0.011), use of TT (HR 0.43, p = 0.001), controlled primary disease (HR 0.63, p = 0.047), and single BM (HR 0.55, p = 0.016). Significant factors for LC were gross total resection (HR 0.29, p = 0.014) and origin of cancer (p = 0.041). Both WBRT and LBRT/SRS showed superior LC than no radiation (HR 0.32, p = 0.034 and HR 0.38, p = 0.018, respectively). Significant factors for DC were use of TT (HR 0.54, p = 0.022) and single BM (HR 0.47, p = 0.004). Reduced incidence of LMM was associated with use of TT (HR 0.42, p = 0.038), synchronicity (HR 0.25, p = 0.028), and controlled primary cancer (HR 0.44, p = 0.047). TT was associated with prolonged OS, improved DC, and reduced LMM in resected BM patients. WBRT and LBRT/SRS showed similar benefits on LC. Considering the extended survival of cancer patients and the long-term effect of WBRT on cognitive function, LBRT/SRS appears to be a good option after resection of BM.

Effective Organs-at-Risk Dose Sparing in Volumetric Modulated Arc Therapy Using a Half-Beam Technique in Whole Pelvic Irradiation.

BACKGROUND: Although there are some controversies regarding whole pelvic radiation therapy (WPRT) due to its gastrointestinal and hematologic toxicities, it is considered for patients with gynecological, rectal, and prostate cancer. To effectively spare organs-at-risk (OAR) doses using multi-leaf collimator (MLC)'s optimal segments, potential dosimetric benefits in volumetric modulated arc therapy (VMAT) using a half-beam technique (HF) were investigated for WPRT. METHODS: While the size of a fully opened field (FF) was decided to entirely include a planning target volume in all beam's eye view across arc angles, the HF was designed to use half the FF from the isocenter for dose optimization. The left or the right half of the FF was alternatively opened in VMAT-HF using a pair of arcs rotating clockwise and counterclockwise. Dosimetric benefits of VMAT-HF, presented with dose conformity, homogeneity, and dose-volume parameters in terms of modulation complex score, were compared to VMAT optimized using the FF (VMAT-FF). Consequent normal tissue complication probability (NTCP) by reducing the irradiated volumes was evaluated as well as dose-volume parameters with statistical analysis for OAR. Moreover, beam-on time and MLC position precision were analyzed with log files to assess plan deliverability and clinical applicability of VMAT-HF as compared to VMAT-FF. RESULTS: While VMAT-HF used 60%-70% less intensity modulation complexity than VMAT-FF, it showed superior dose conformity. The small intestine and colon in VMAT-HF showed a noticeable reduction in the irradiated volumes of up to 35% and 15%, respectively, at an intermediate dose of 20-45 Gy. The small intestine showed statistically significant dose sparing at the volumes that received a dose from 15 to 45 Gy. Such a dose reduction for the small intestine and colon in VMAT-HF presented a significant NTCP reduction from that in VMAT-FF. Without sacrificing the beam delivery efficiency, VMAT-HF achieved effective OAR dose reduction in dose-volume histograms. CONCLUSIONS: VMAT-HF led to deliver conformal doses with effective gastrointestinal-OAR dose sparing despite using less modulation complexity. The dose of VMAT-HF was delivered with the same beam-on time with VMAT-FF but precise MLC leaf motions. The VMAT-HF potentially can play a valuable role in reducing OAR toxicities associated with WPRT.

Impact of Body Mass Index on Local Recurrence according to Intrinsic Subtype Approximation in Korean Women with Early Stage Invasive Breast Cancer Receiving Contemporary Treatments.

Purpose: We investigated the prognostic impact of body mass index (BMI) on local recurrence (LR) according to intrinsic subtype in Korean women with early stage, invasive breast cancer. Materials and methods: We included 907 patients with pathological stage T1-2 and N0-1 breast cancer who underwent curative surgery between 2007 and 2012. Systemic treatments were administered in 876 patients (96.6%). In total, 701 patients (77.3%) received radiotherapy. Intrinsic subtypes were determined using immunohistochemical staining results. Results: During the median follow-up period of 72 months, LR as the first failure occurred in 29 patients, including 24 patients with isolated LR. The 5-year cumulative incidence rate of LR was 3.2% among all patients. In the luminal A subtype, a BMI of <18.5 kg/m2 was an independent risk factor for LR, as determined by a competing-risk regression model (relative risk, 3.33; p = 0.041). Severely obese patients (BMI >30 kg/m2) with the triple negative subtype had an increased risk of LR (relative risk, 3.81; p = 0.048). Conclusion: The present study identified traditionally underestimated risk groups for LR. BMI may diversely influence the rate of LR across intrinsic subtypes in Korean patients with breast cancer.

Local Recurrence in Young Women with Breast Cancer: Breast Conserving Therapy vs. Mastectomy Alone.

We compared the cumulative incidence of local recurrence in young patients (≤40 years) with breast cancer between breast conserving therapy (BCT) and mastectomy alone. Among 428 women with early-stage breast cancer who were treated between 2001 and 2012, 311 underwent BCT and 117 underwent mastectomy alone. Adjuvant systemic treatments were administered to 409 patients (95.6%). We compared the cumulative incidence of LR and survival rates between two groups. During a median follow-up period of 91 months, the 10-year cumulative incidence of LR was 9.3% (median interval of 36.5 months from surgery). Patients treated with BCT tended to have a higher risk for local recurrence (11.1% for BCT vs. 4.1% for mastectomy alone, p = 0.078). All patients with isolated LR after BCT (n = 23) underwent salvage mastectomy followed by systemic treatments. The 5-year distant metastasis-free survival and overall survival of patients with isolated LR after BCT were 44.2% and 82.2%, respectively. The BCT group exhibited an approximately 2.5-fold higher risk of LR than mastectomy alone group. Patients with isolated LR after BCT showed poor prognosis despite undergoing aggressive salvage treatments. The development of novel treatments should be investigated to reduce LR for improving prognosis and preserving cosmetic outcomes in young women.