Long-term outcomes and risk profile of cT3N0 breast cancer treated with neoadjuvant chemotherapy and curative surgery.

INTRODUCTION: We evaluated the treatment outcomes and failure patterns in cT3N0 breast cancer patients classified for rigorous pretreatment evaluation and treated with neoadjuvant chemotherapy (NAC) and curative surgery. METHODS: We reviewed the records of 87 cT3N0 breast cancer patients who received NAC and curative surgery between 2000 and 2015. The clinical high-risk group was defined as having two or more risk factors: age < 40, histologic grade 3, lymphovascular invasion, hormone receptor negativity, and Ki-67 labeling index >20%. RESULTS: Of the patients, 84 (96.6%) and 79 (90.8%) were initially evaluated using magnetic resonance imaging and positron emission tomography/computed tomography. Most patients received anthracycline based NAC regimen (n = 69, 79.3%) and modified radical mastectomy (n = 61, 70.1%). During a 91.5-month median follow-up, ten patients experienced distant metastasis (DM) only, two had isolated local recurrence, one had local recurrence and DM, and another had local recurrence, regional recurrence, and DM. The 5-year rates of locoregional recurrence, DM, any recurrence (AR), and overall survival (OS) were 1.2%, 11.6%, 11.6%, and 90.8%, respectively. The risk group was an independent prognostic factor of recurrence, and the high-risk group had worse rates of DM (19.2% vs. 0%, P = 0.009), AR (19.2% vs. 0%, P = 0.016) and OS (82.8% vs. 100%, P = 0.001). CONCLUSION: Patients with cT3N0 breast cancer classified for rigorous pretreatment evaluation and treated with NAC and radical surgery had favourable oncological outcomes. A clinical risk group based on clinical and immunohistochemical risk factors was an excellent predictor of survival and recurrence.

Intensive Surveillance for Women With Breast Cancer: A Multicenter Retrospective Study in Korea.

PURPOSE: This study evaluated the effectiveness of different surveillance intensities on morbidity and mortality in women with breast cancer. METHODS: This retrospective study included patients who had undergone breast cancer surgery in the Republic of Korea between 2009 and 2011. The patients were divided into two groups based on the intensity of their postsurgical surveillance: intensive surveillance group (ISG) and less-intensive surveillance group. Surveillance intensity was measured based on the frequency and type of follow-up diagnostic tests conducted, including mammography, ultrasonography, computed tomography, magnetic resonance imaging, bone scans, and positron emission tomography scans. RESULTS: We included 1,356 patients with a median follow-up period of 121.2 months (range, 12.8-168.0 months). The analysis revealed no significant difference in the overall survival (OS) between the two groups within five years of surgery. However, patients with ISG exhibited significantly better breast cancer-specific survival (BCSS) and distant metastasis-free survival (DMFS) within the same period. Five years after surgery, the differences in survival outcomes between the groups were not statistically significant. CONCLUSION: Intensive surveillance did not demonstrate a significant improvement in OS for patients with breast cancer beyond five years postoperatively. However, within the first five years, intensive surveillance was associated with better BCSS and DMFS. These findings suggest that personalized surveillance strategies may benefit specific patient subsets, particularly in the early years after treatment. Further nationwide randomized studies are warranted to refine surveillance guidelines and optimize outcomes in patients with breast cancer.

Predicting Long-Term Engagement in mHealth Apps: Comparative Study of Engagement Indices.

BACKGROUND: Digital health care apps, including digital therapeutics, have the potential to increase accessibility and improve patient engagement by overcoming the limitations of traditional facility-based medical treatments. However, there are no established tools capable of quantitatively measuring long-term engagement at present. OBJECTIVE: This study aimed to evaluate an existing engagement index (EI) in a commercial health management app for long-term use and compare it with a newly developed EI. METHODS: Participants were recruited from cancer survivors enrolled in a randomized controlled trial that evaluated the impact of mobile health apps on recovery. Of these patients, 240 were included in the study and randomly assigned to the Noom app (Noom Inc). The newly developed EI was compared with the existing EI, and a long-term use analysis was conducted. Furthermore, the new EI was evaluated based on adapted measurements from the Web Matrix Visitor Index, focusing on click depth, recency, and loyalty indices. RESULTS: The newly developed EI model outperformed the existing EI model in terms of predicting EI of a 6- to 9-month period based on the EI of a 3- to 6-month period. The existing model had a mean squared error of 0.096, a root mean squared error of 0.310, and an R2 of 0.053. Meanwhile, the newly developed EI models showed improved performance, with the best one achieving a mean squared error of 0.025, root mean squared error of 0.157, and R2 of 0.610. The existing EI exhibited significant associations: the click depth index (hazard ratio [HR] 0.49, 95% CI 0.29-0.84; P<.001) and loyalty index (HR 0.17, 95% CI 0.09-0.31; P<.001) were significantly associated with improved survival, whereas the recency index exhibited no significant association (HR 1.30, 95% CI 1.70-2.42; P=.41). Among the new EI models, the EI with a menu combination of menus available in the app's free version yielded the most promising result. Furthermore, it exhibited significant associations with the loyalty index (HR 0.32, 95% CI 0.16-0.62; P<.001) and the recency index (HR 0.47, 95% CI 0.30-0.75; P<.001). CONCLUSIONS: The newly developed EI model outperformed the existing model in terms of the prediction of long-term user engagement and compliance in a mobile health app context. We emphasized the importance of log data and suggested avenues for future research to address the subjectivity of the EI and incorporate a broader range of indices for comprehensive evaluation.

Dual-Action Protein-siRNA Conjugates for Targeted Disruption of CD47-Signal Regulatory Protein α Axis in Cancer Therapy.

A series of successes in RNA interference (RNAi) therapies for liver diseases using lipid nanoparticles and N-acetylgalactosamine have heralded a current era of RNA therapeutics. However, alternative delivery strategies are required to take RNAi out of the comfort zone of hepatocytes. Here we report SIRPα IgV/anti-CD47 siRNA (vS-siCD47) conjugates that selectively and persistently disrupt the antiphagocytic CD47/SIRPα axis in solid tumors. Conjugation of the SIRPα IgV domain protein to siRNAs enables tumor dash through CD47-mediated erythrocyte piggyback, primarily blocking the physical interaction between CD47 on cancer cells and SIRPα on phagocytes. After internalization of the vS-siCD47 conjugates within cancer cells, the detached free-standing anti-CD47 siRNAs subsequently attack CD47 through the RNAi mechanism. The dual-action approach of the vS-siCD47 conjugate effectively overcomes the "don't eat me" barrier and stimulates phagocyte-mediated tumor destruction, demonstrating a highly selective and potent CD47-blocking immunotherapy. This delivery strategy, employing IgV domain protein-siRNA conjugates with a dual mode of target suppression, holds promise for expanding RNAi applications beyond hepatocytes and advancing RNAi-based cancer immunotherapies for solid tumors.

Longitudinal dynamics of circulating tumor DNA for treatment monitoring in patients with breast cancer recurrence.

The prevalence and dynamics of circulating tumor DNA (ctDNA) in patients with breast cancer recurrence or de novo metastatic cancer were examined in a retrospective analysis of a prospective observational cohort. Twenty-three recurrent/metastatic breast cancer cases (8 locoregional, 15 distant metastasis) were enrolled, and sequential plasma samples were obtained. Anchor mutations were selected from the target sequencing of each patient's primary and/or metastatic tumor. An in-house developed assay (UHS assay) was employed for a tumor-informed ctDNA assay during treatment and follow-up. A median of three (range 1-5) anchor mutations per case were applied for ctDNA detection. ctDNA was detected in 14 (63.6%, 14/22) cases at the time of enrollment and 18 (78.5%, 18/23) cases during follow-up. More anchor mutations and higher tumor burden were significantly related to higher ctDNA positive rates (p-value 0.036, 0.043, respectively). The mean enriched variant allele frequency (eVAF) at each time point was significantly higher for stable or progressive disease responses (ANOVA test p-value < 0.001). Eight patients showed an increase in their ctDNA eVAF prior to clinical progression with a mean lead time of 6.2 months (range 1.5-11 months). ctDNA dynamics measured using personalized assay reflected the clinical course of breast cancer recurrence.

Surveillance for Distant Metastasis in Breast Cancer Patients Who Underwent Contemporary Management: A Report from the Korean Breast Cancer Society Survivor Research Group.

BACKGROUND: Current guidelines recommend against the use of routine imaging tests to detect distant metastasis in asymptomatic breast cancer patients. However, recent advancements in effective therapeutics and diagnostic accuracy have raised the need to reassess the clinical efficacy of intensive metastasis surveillance. We report the results of a multicenter retrospective study to investigate the association between intensive imaging studies and survival outcomes. PATIENTS AND METHODS: We retrospectively reviewed the data of 4130 patients who underwent surgery from 11 hospitals in Korea between January 2010 and December 2011. Patients were divided into two groups on the basis of the intensity of metastasis imaging studies during their disease-free period. The types and intervals of the imaging studies were based on each physician's decisions. RESULTS: High-intensive screening showed a shorter distant metastasis-free survival [p < 0.001, hazard ratio (HR) 1.62; 95% confidence interval (CI) 1.29-2.04], especially for patients in whom bone or lung was the first site of metastasis. With a median follow-up period of 110.0 months, the 5-year breast cancer-specific survival (BCSS) rate was 96.5%. The high-intensity screening group showed significantly poorer BCSS compared with the low-intensity screening group (p < 0.001, HR 3.13; 95% CI 2.32-4.21). However, both multivariable analysis and propensity score matching analysis showed no significant association between the screening intensity and BCSS. CONCLUSIONS: Frequent imaging studies to detect distant metastasis were associated with earlier detection of distant metastasis, especially for lung and bone metastasis. However, intensive surveillance showed no apparent association with BCSS despite the use of currently available treatments.

Survival pattern in male breast cancer: distinct from female breast cancer.

Introduction: Male breast cancer (MBC) is a rare condition, and recent research has underscored notable distinctions between MBC and breast cancer in women. This study aimed to assess and contrast the long-term survival outcomes and disease patterns of MBC patients with those of their female counterparts. Methods: We analyzed data from 113,845 patients diagnosed with breast cancer who had undergone curative surgery from the Korean Breast Cancer Registry (KBCR) between January 1990 and August 2014 in Seoul, Korea. The five-year overall survival was analyzed according to clinicopathological characteristics. Results: Among 113,845 patients with breast cancer, 473 MBC cases were included. The median duration of follow-up was 72 months. The median age at diagnosis was 60 and 48 years for MBC and female breast cancer, respectively. Most male patients (92.6%) underwent total mastectomy, while 50.4% of female patients underwent breast-conserving surgery. Among MBC, 63.2% received chemotherapy, and 83.9% of hormone receptor-positive male patients received endocrine therapy. In survival analysis, MBC demonstrated distinct 5-year overall survival patterns compared with female breast cancer, according to age at diagnosis. In women with breast cancer, the younger age group (≤40 years) demonstrated worse 5-year overall survival than did the older age group (>40 years) (91.3% vs 92.7%, p <0.05). While in MBC, the younger age group (≤40 years) demonstrated better 5-year overall survival than did the older age group (>40 years) (97.4% vs 86.4%, p <0.05). Discussion: In conclusion within this extensive cohort, we have revealed unique survival patterns in MBC that diverge from those observed in women with breast cancer. This study enhances our comprehension of MBC prognosis and can potentially shed light on unresolved questions, paving the way for future research in the realm of MBC.

Targeted delivery of anti-miRNA21 sensitizes PD-L1high tumor to immunotherapy by promoting immunogenic cell death.

Rationale: Growing evidence has demonstrated that miRNA-21 (miR-21) upregulation is closely associated with tumor pathogenesis. However, the mechanisms by which miR-21 inhibition modulates the immunosuppressive tumor microenvironment (TME) and improves tumor sensitivity to immune checkpoint blockade therapies remain largely unexplored. In this study, we demonstrate the precise delivery of anti-miR-21 using a PD-L1-targeting peptide conjugate (P21) to the PD-L1high TME. Methods: Investigating miR-21 inhibition mechanisms involved conducting quantitative real-time PCR, western blot, flow cytometry, and confocal microscopy analyses. The antitumor efficacy and immune profile of P21 monotherapy, or combined with anti-PD-L1 immune checkpoint inhibitors, were assessed in mouse models bearing CT26.CL25 tumors and 4T1 breast cancer. Results Inhibition of oncogenic miR-21 in cancer cells by P21 efficiently activates tumor suppressor genes, inducing autophagy and endoplasmic reticulum stress. Subsequent cell-death-associated immune activation (immunogenic cell death) is initiated via the release of damage-associated molecular patterns. The in vivo results also illustrated that the immunogenic cell death triggered by P21 could effectively sensitize the immunosuppressive TME. That is, P21 enhances CD8+ T cell infiltration in tumor tissues by conferring immunogenicity to dying cancer cells and promoting dendritic cell maturation. Meanwhile, combining P21 with an anti-PD-L1 immune checkpoint inhibitor elicits a highly potent antitumor effect in a CT26.CL25 tumor-bearing mouse model and 4T1 metastatic tumor model. Conclusions: Collectively, we have clarified a miR-21-related immunogenic cell death mechanism through the precise delivery of anti-miR-21 to the PD-L1high TME. These findings highlight the potential of miR-21 as a target for immunotherapeutic interventions.

Evaluation of safety and operative time in tumescent-free robotic nipple-sparing mastectomy: a retrospective single-center cohort study.

Purpose: Tumescent in nipple-sparing mastectomy (NSM) has been reported to increase the risk of necrosis by impairing blood flow to the skin flap and nipple-areolar complex. At our institution, we introduced a tumescent-free robotic NSM using the da Vinci single-port system (Intuitive Surgical, Inc.). Methods: We conducted a retrospective analysis of patients who underwent tumescent-free robotic NSM between October 2020 and March 2023 at Asan Medical Center (Seoul, Korea). Clinicopathological characteristics, adverse events, and operative time were evaluated. Results: During the study period, 118 patients underwent tumescent-free robotic NSM. Thirty-one patients (26.3%) experienced an adverse event. Five patients (4.2%) were classified as grade III based on the Clavien-Dindo classification and required surgery. The mean total operative time was 467 minutes for autologous tissue reconstruction (n = 49) and 252 minutes for implants (n = 69). No correlation was found between the cumulative number of surgical cases and the breast operative time (P = 0.30, 0.52, 0.59 for surgeons A, B, C) for the 3 surgeons. However, a significant linear relationship (P < 0.001) was observed, with the operative time increasing by 13 minutes for every 100-g increase in specimen weight. Conclusion: Tumescent-free robotic NSM is a safe procedure with a feasible operative time and few adverse events.

Association of residual ductal carcinoma in situ with breast cancer treatment outcomes after neoadjuvant chemotherapy according to hormone receptor status.

PURPOSE: This research aimed to clarify the impact of residual ductal carcinoma in situ(DCIS) in surgical specimens obtained after neoadjuvant chemotherapy(NAC) for breast cancer on the associated prognosis outcomes. METHODS: This retrospective study was performed on a cohort of 1,009 patients who achieved pCR following NAC for breast cancer and underwent subsequent breast surgery at a single institution between January 2008 and December 2019. Overall survival, local recurrence-free survival, distant metastasis-free survival, and disease-free survival of the residual and non-residual DCIS groups were the outcomes compared, with further subgroup analysis performed according to hormone receptor status. RESULTS: 260 individuals (25.8%) presented with residual DCIS. Based on a median follow-up of 54.0 months, no significant differences in outcomes were observed between the two groups. Patients with residual DCIS and hormone receptor-negative (HR-) breast cancer demonstrated a significant decrease in distant metastasis-free survival (p = 0.030) compared to those without residual DCIS. In the HR + cohort, no significant difference was observed between the two groups. Multivariate analysis of the HR- cohort demonstrated a significant association between residual DCIS and an elevated risk for distant recurrence (hazard ratio = 2.3, 95% confidence interval = 1.01-5.20, p = 0.047). CONCLUSIONS: Residual DCIS following NAC may impact breast cancer outcomes, particularly with respect to the occurrence of distant metastasis in HR- patients. Therefore, clinicians must vigilantly monitor patients with residual DCIS after NAC, and further research is needed to expand our understanding of the clinical implications of residual DCIS.

Chemically induced cone degeneration in the 13-lined ground squirrel.

Animal models of retinal degeneration are critical for understanding disease and testing potential therapies. Inducing degeneration commonly involves the administration of chemicals that kill photoreceptors by disrupting metabolic pathways, signaling pathways, or protein synthesis. While chemically induced degeneration has been demonstrated in a variety of animals (mice, rats, rabbits, felines, 13-lined ground squirrels (13-LGS), pigs, chicks), few studies have used noninvasive high-resolution retinal imaging to monitor the in vivo cellular effects. Here, we used longitudinal scanning light ophthalmoscopy (SLO), optical coherence tomography, and adaptive optics SLO imaging in the euthermic, cone-dominant 13-LGS (46 animals, 52 eyes) to examine retinal structure following intravitreal injections of chemicals, which were previously shown to induce photoreceptor degeneration, throughout the active season of 2019 and 2020. We found that iodoacetic acid induced severe pan-retinal damage in all but one eye, which received the lowest concentration. While sodium nitroprusside successfully induced degeneration of the outer retinal layers, the results were variable, and damage was also observed in 50% of contralateral control eyes. Adenosine triphosphate and tunicamycin induced outer retinal specific damage with varying results, while eyes injected with thapsigargin did not show signs of degeneration. Given the variability of damage we observed, follow-up studies examining the possible physiological origins of this variability are critical. These additional studies should further advance the utility of chemically induced photoreceptor degeneration models in the cone-dominant 13-LGS.

Characteristics and risk factors of axillary lymph node metastasis of microinvasive breast cancer.

PURPOSE: To select patients who would benefit most from sentinel lymph node biopsy (SLNB) by investigating the characteristics and risk factors of axillary lymph node metastasis (ALNM) in microinvasive breast cancer (MIBC). METHODS: This retrospective study included 1688 patients with MIBC who underwent breast surgery with axillary staging at the Asan Medical Center from 1995 to 2020. RESULTS: Most patients underwent SLNB alone (83.5%). Seventy (4.1%) patients were node-positive, and the majority had positive lymph nodes < 10 mm, with micro-metastases occurring frequently (n = 37; 55%). Node-positive patients underwent total mastectomy and axillary lymph node dissection (ALND) more than breast-conserving surgery (BCS) and SLNB compared with node-negative patients (p < 0.001). In the multivariate analysis, independent predictors of ALNM included young age [odds ratio (OR) 0.959; 95% confidence interval (CI) 0.927-0.993; p = 0.019], ALND (OR 11.486; 95% CI 5.767-22.877; p < 0.001), number of lymph nodes harvested (≥ 5) (OR 3.184; 95% CI 1.555-6.522; p < 0.001), lymphovascular invasion (OR 6.831; 95% CI 2.386-19.557; p < 0.001), presence of multiple microinvasion foci (OR 2.771; 95% CI 1.329-5.779; p = 0.007), prominent lymph nodes in preoperative imaging (OR 2.675; 95% CI 1.362-5.253; p = 0.004), and hormone receptor positivity (OR 2.491; 95% CI 1.230-5.046; p = 0.011). CONCLUSION: Low ALNM rate (4.1%) suggests that routine SLNB for patients with MIBC is unnecessary but can be valuable for patients with specific risk factors. Ongoing trials for omitting SLNB in early breast cancer, and further subanalyses focusing on rare populations with MIBC are necessary.

Implementation of BRCA Test among Young Breast Cancer Patients in South Korea: A Nationwide Cohort Study.

PURPOSE: This study aimed to investigate the frequency of BRCA testing and related factors among young breast cancer patients (age < 40 years) in South Korea. MATERIALS AND METHODS: We conducted a nationwide retrospective cohort study using data from the Health Insurance Review and Assessment claims. Newly diagnosed breast cancer patients younger than 40 were included. Annual BRCA testing ratios (number of BRCA test recipients/the number of patients undergoing breast cancer surgery in each year) were analyzed by region and health care delivery system. We investigated the location of breast cancer diagnosis and BRCA testing. RESULTS: From January 2010 to December 2020, there were 25,665 newly diagnosed young breast cancer patients, of whom 12,186 (47.5%) underwent BRCA testing. The BRCA testing ratios increased gradually from 0.084 (154/1,842) in 2010 to 0.961 (1,975/2,055) in 2020. Medical aid (vs. health insurance) and undergoing surgery in metropolitan cities or others (vs. Seoul), general hospitals, and clinics (vs. tertiary hospitals) were associated with a lower likelihood of BRCA testing. While 97.8% of the patients diagnosed in Seoul underwent BRCA testing in Seoul, 22.9% and 29.2% of patients who were diagnosed in metropolitan areas and other regions moved to Seoul and underwent BRCA testing, respectively. CONCLUSION: The frequency of BRCA testing has increased over time in South Korea, with Seoul showing a particularly high rate of testing. About one-quarter of patients diagnosed with breast cancer outside of Seoul moved to Seoul and underwent BRCA testing.

Characterization of temperature-dependent subcritical water hydrolysis pattern of strong and floury rice cultivars and potential utilizations of their hydrolysates.

This study investigated the effects of subcritical water (SW) temperatures on the hydrolysis pattern and characteristics of hydrolysates prepared with strong rice (SR) and floury rice (FR). The characteristics of the hydrolysates were generally dependent on the rice cultivar in the SW temperature range of 150-250 °C, while the cultivar dependence was diminished at temperatures greater than 300 °C. Based on brix and reducing sugar content, an optimal production of rice hydrolysates was obtained at a SW temperature range of 200-250 °C. However, thermal conversion of sugar into acids, 5-hydroxymethylfurfural (HMF) and furfural was manifested at 250 °C. The rice hydrolysates prepared at 250 âˆ¼ 300 °C had the highest antioxidant activity with strong umami intensity, but they suppressed the growth of prebiotics. Therefore, the present study demonstrated that controlling the SW temperature is crucial to improve rice hydrolysis efficiency and to regulate the physiological activity of the hydrolysates.

Oncological Safety of Skipping Axillary Lymph Node Dissection in Patients with Clinical N0, Sentinel Node-Positive Breast Cancer Undergoing Total Mastectomy.

OBJECTIVE: This study aimed to determine whether sentinel lymph node biopsy (SLNB) alone could afford oncological outcomes comparable with axillary lymph node dissection (ALND) in patients with early breast cancer without palpable lymphadenopathy who underwent total mastectomy (TM) and were SLN-positive. METHODS: This study analyzed clinical data of 6747 patients with breast cancer who underwent TM between 2014 and 2018 in two tertiary hospitals in Korea. Overall, 643 clinical stage T1-3 N0 patients who did not receive neoadjuvant therapy and had one to two metastatic SLNs at the time of surgery were included. Propensity score matching was performed between the SLNB alone and ALND groups, adjusting for clinical T stage and number of metastatic SLNs. In total, 237 patients were allocated to each group. RESULTS: Mean number of metastatic SLNs was 1.2 for the SLNB group and 1.6 for the ALND group. With a median follow-up of 65.0 months, 5 year disease-free survival was 90.8% for the SLNB group and 93.9% for the ALND group (hazard ratio [HR] 1.35, 95% confidence interval [CI] 0.70-2.58; p = 0.36). 5 year ipsilateral locoregional recurrence-free survival (LRRFS) was not significantly different between the two groups (95.1% and 98.3% for the SLNB and ALND groups, respectively) [HR 1.86, 95% CI 0.69-5.04; p = 0.21]. In the SLNB group, patients who received radiation therapy (RT) showed superior 5 year LRRFS than patients who did not receive RT (100% vs. 92.9%; p = 0.02). CONCLUSION: Collectively, our findings suggest that SLNB could afford comparable outcomes to ALND in patients with early breast cancer and one to two metastatic SLNs who underwent TM. Importantly, RT could decrease locoregional recurrence in patients who underwent SLNB alone.

Comparison of long-term oncological outcomes after central lumpectomy versus nipple-sparing breast-conserving surgery for centrally located breast cancer: a propensity score-matched study.

PURPOSE: To compare the oncological safety of nipple-sparing breast-conserving surgery (BCS) versus central lumpectomy for centrally located breast cancer (CLBC). METHODS: Patients who underwent BCS for CLBC at Asan Medical Center from 2007 to 2018 were reviewed retrospectively. The oncological outcomes of nipple-sparing BCS (NS-BCS) and central lumpectomy were compared using univariate and multivariate Cox regression analyses and compared again after 1:1 propensity score matching (PSM). RESULTS: The study included 306 patients who underwent NS-BCS and 106 patients who underwent central lumpectomy (median follow-up: 111 months). On multivariate analysis, central lumpectomy had a lower risk of local recurrence compared to NS-BCS, albeit without statistical significance (HR 0.14, 95% CI 0.02-1.24; p = 0.077). There was no significant difference in the risk of death (HR 0.14, 95% CI 0.01-1.68, p = 0.12). After PSM, each group had 106 patients. The 5-year and 10-year local recurrence-free survival rates were 94.2% and 92.9% for NS-BCS, and 99.1% and 99.1% for central lumpectomy, respectively (p = 0.031). There were no significant differences in overall survival, regional recurrence-free survival, or distant recurrence-free survival. Fifteen patients (4.9%) who underwent NS-BCS had ipsilateral breast tumor recurrence (IBTR), of which 40% were in the nipple-areolar complex and previous surgical sites. One patient (0.9%) who underwent central lumpectomy experienced an IBTR in a different quadrant. CONCLUSION: NS-BCS showed more local recurrence than central lumpectomy. When deciding whether to spare the nipple during BCS in CLBC, patients should be sufficiently informed about the risk of IBTR.

Clinical Efficacy of Mobile App-Based, Self-Directed Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease: Systematic Review and Meta-Analysis.

Background: Pulmonary rehabilitation is well known to improve clinical symptoms (including dyspnea), quality of life, and exercise capacity in patients with chronic obstructive pulmonary disease (COPD). However, researchers have reported difficulties in practicing center-based pulmonary rehabilitation. Recently, mobile app-based pulmonary rehabilitation has become available in clinical practice. We investigated the clinical outcomes of mobile app-based pulmonary rehabilitation in patients with COPD. Objective: The objective of our study was to evaluate the clinical efficacy of mobile app-based pulmonary rehabilitation versus conventional center-based pulmonary rehabilitation for patients with COPD, using a systematic review and meta-analysis. Methods: A systematic search of the literature published between January 2007 and June 2023 was performed, using the PubMed, Embase, Cochrane, and CINAHL databases to identify relevant randomized controlled trials involving patients with COPD. Pulmonary rehabilitation programs needed to provide an exercise program on a smartphone app. Study outcomes, including exercise capacity, symptom scores, quality of life, and hospitalization, were evaluated. The meta-analysis evaluated mean differences in 6-minute walk test distances (6MWDs), COPD Assessment Test (CAT) scores, modified Medical Research Council (mMRC) dyspnea scale scores, St. George Respiratory Questionnaire (SGRQ) scores, and risk ratios for hospitalization resulting from disease exacerbation. Results: Of the 1173 screened studies, 10 were included in the systematic review and 9 were included in the meta-analysis. Further, 6 studies were multicenter studies. There were a total of 1050 participants, and most were aged ≥65 years. There were discrepancies in the baseline participant characteristics, smartphone apps, interventions, and study outcomes among the included studies. In the meta-analysis, 5 studies assessed 6MWDs (mean difference 9.52, 95% CI -3.05 to 22.08 m), 6 studies assessed CAT scores (mean difference -1.29, 95% CI -2.39 to -0.20), 3 studies assessed mMRC dyspnea scale scores (mean difference -0.08, 95% CI -0.29 to 0.13), 2 studies assessed SGRQ scores (mean difference -3.62, 95% CI -9.62 to 2.38), and 3 studies assessed hospitalization resulting from disease exacerbation (risk ratio 0.65, 95% CI 0.27-1.53). These clinical parameters generally favored mobile app-based pulmonary rehabilitation; however, a statistically significant difference was noted only for the CAT scores (P=.02). Conclusions: Despite some discrepancies in the baseline participant characteristics and interventions among studies, mobile app-based pulmonary rehabilitation resulted in favorable exercise capacity, symptom score, quality of life, and hospitalization outcomes when compared with conventional pulmonary rehabilitation. In the meta-analysis, the CAT scores of the mobile app-based pulmonary rehabilitation group were significantly lower than those of the control group (P=.02). In real-world practice, mobile app-based pulmonary rehabilitation can be a useful treatment option when conventional center-based pulmonary rehabilitation is not feasible.

Diagnostic yield of contrast-enhanced abdominal staging CT in patients with initially diagnosed breast cancer.

PURPOSE: To estimate the diagnostic yield (DY) of abdominal staging CT for detecting breast cancer liver metastasis (BCLM) in patients with initially diagnosed breast cancer and to determine the indications for abdominal staging CT. METHODS: Patients with newly diagnosed breast cancer who underwent abdominal CT as an initial staging work-up between January 2019 and December 2020 were retrospectively analyzed. DY was calculated and analyzed according to patient age, type of treatments, histologic type, histologic grade, lymphovascular invasion, Ki-67 status, hormone receptor status, subtype, and the American Joint Committee on Cancer anatomical staging. RESULTS: A total of 2056 patients (mean age, 51 ± 11 years) were included. The DY of abdominal staging CT for detecting BCLM was 1.1 % (22 of 2056). DY was significantly higher in stage III than in stage I or II cancers (3.9 % [18 of 467] vs. 0 % [0 of 412] or 0.4 % [4 of 1158], respectively, p < .001), and in human epidermal growth factor receptor-2 (HER2)-enriched cancers than in luminal or triple negative cancers (2.9 % [16 of 560] vs. 0.4 % [4 of 1090] or 0.5 % [2 of 406], respectively, p < .001). CONCLUSIONS: The DY of abdominal staging CT for detecting BCLM was low among all patients with initially diagnosed breast cancer. However, although abdominal staging CT for detecting BCLM is probably unnecessary in all patients, it can be clinically useful in patients with stage III or human epidermal growth factor receptor-2-enriched breast cancers.

21-gene expression assay and clinical outcomes of premenopausal patients with hormone receptor-positive breast cancer.

The prognostic role of the recurrence score (RS) based on the 21-gene expression assay in premenopausal women is not well delineated, and we investigated the association of outcomes and the RS in premenopausal patients who had 21-gene expression assay at Asan Medical Center, Seoul, Korea, between June 2005 and July 2018. Invasive breast cancer-free survival (IBCFS) by STEEP version 2.0 was compared according to the RS and clinical risk factors. A total of 554 patients were included in our study and 116 patients (20.9%) had age <40 years, 238 patients (43.0%) had luminal B subtype (Ki67 ≥ 20%), and 83 patients (15.0%) had RS >25. All patients received adjuvant tamoxifen ± chemotherapy. Overall, patients with RS >25 showed trend toward worse IBCFS from multivariable analysis (adjusted HR 1.89 [95% CI: 0.95-3.73], P = .069). When comparing outcomes according to age and luminal subtypes, patients with luminal B subtype and age <40 years (n = 60) showed significantly worse outcomes compared to the others (luminal A or luminal B + age ≥40 years, n = 494; adjusted HR 2.95 [95% CI: 1.49-5.82], log-rank P < .001). Among patients with luminal B subtype and age <40 years, there was no significant association observed between IBCFS and the RS (log-rank P = .51). In conclusion, while RS >25 showed association with poor outcomes in premenopausal women, it may have less prognostic significance among those with luminal B subtype and age <40 years.

Long-term outcome in patients with nodal-positive breast cancer treated with sentinel lymph node biopsy alone after neoadjuvant chemotherapy.

PURPOSE: Sentinel lymph node biopsy (SLNB) has yet to be accepted as the standard staging procedure in node positive (cN1) breast cancer patients who had clinical complete response in the axilla (cN0) following neoadjuvant chemotherapy (NAC), due to the presumed high false negative rate associated with SLNB in such scenario. This study aimed to determine whether there is a significant difference in the axillary recurrence rate (ARR) and long-term survival in this group of patients, receiving SLNB alone versus axillary lymph node dissection (ALND). METHODS: A retrospective cohort of cN1 patients who were rendered cN0 by NAC from January 2014 to December 2018 were identified from the Asan Medical Center database. Patients' characteristics and outcomes were collected and analyzed. RESULTS: 902 cN1 patients treated with NAC and turned cN0 were identified. 477 (52.9%) patients achieved complete pathological response in the axilla (ypN0). At a median follow up of 65 months, ARR was 3.2% in the SLNB only group and 1.8% in the ALND group (p = 0.398). DFS and OS were significantly worse in patients with ALND as compared to patients with SLNB only (p = 0.011 and 0.047, respectively). We noted more patients in the ALND group had T3-4 tumor. In the subgroup analysis, we showed that in the T1-2 subgroup (n = 377), there was no statistically significant difference in DFS and OS (p = 0.242 and 0.671, respectively) between SLNB only and ALND group. CONCLUSION: Our findings suggest that cN1 patients who were converted to ypN0 following NAC may be safely treated with SLNB only.