Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: s/Aims: Minimally invasive pancreatoduodenectomy (MIPD), such as totally laparoscopic pancreatoduodenectomy (TLPD) or robot-assisted pancreatoduodenectomy (RAPD), is increasingly performed worldwide. This study aimed to compare the perioperative outcomes of TLPD and RAPD, and compare the oncologic outcomes between MIPD and open pancreatoduodenectomy (OPD) for malignant disease. Methods: This retrospective study was conducted at two hospitals that followed similar oncological surgical principles, including the extent of resection. RAPD was performed at Seoul National University Hospital, and TLPD at Seoul National University Bundang Hospital. Patient demographics, perioperative outcomes, and oncological outcomes were analyzed. Propensity score matching (PSM) analysis was performed to compare oncologic outcomes between MIPD and OPD. Results: Between 2015 and 2020, 332 RAPD and 178 TLPD were performed. The rates of Clavian–Dindo grade ≥ 3 complications (19.3% vs. 20.2%, p = 0.816), clinically relevant postoperative pancreatic fistula (9.9% vs. 11.8%, p = 0.647), and open conversions (6.6% vs. 10.5%, p = 0.163) were comparable between the two groups. The mean operation time (341 minutes vs. 414 minutes, p < 0.001) and postoperative hospital stay were shorter in the RAPD group (11 days vs. 14 days, p = 0.034). After PSM, the 5-year overall survival rate was comparable between MIPD and OPD for overall malignant disease (58.4% vs. 55.5%, p = 0.180). Conclusions Both RAPD and TLPD are safe and feasible, and MIPD has clinical outcomes that are comparable to those of OPD. Although RAPD exhibits some advantages, its perioperative outcomes are similar to those associated with TLPD. A surgical method may be selected based on the convenience of surgical movements, medical costs, and operator experience.

Background: We aimed to clarify the safety and efficacy of simultaneous skin exposure to blue, red, and infrared light. The purpose of this study was to confirm the mechanism by which multiple wavelengths increase hair development both in vivo and in vitro. Methods: Cultured human dermal papilla cells (hDPCs) were exposed to a 470/655/850 nm light-emitting diode (LED) array with a fixed energy density of 3.0 mW/cm 2 . We analyzed alkaline phosphatase (ALP) staining and activity. The relative expressions of ALP, VEGF, Shh, and OPN3 were examined using reverse transcriptasepolymerase chain reaction arrays 48 hours post-exposure and the protein levels related to extracellular signalregulated kinase (ERK)/protein kinase B (AKT)/glycogen synthase kinase 3 (GSK3)β signaling were assessed by western blotting. Next, we used H&E staining, hair growth scoring, skin thickness measurement, and the immunohistochemical analysis of the dorsal skin of C57BL/6 mice to investigate the effects of the mono- or combined-photobiomodulation (PBM) groups. Results: According to our findings, simultaneous irradiation with multi-wavelength LEDs at 470/655/850 nm increased the proliferation of hDPCs. Also, compared to the control group, the red wavelength and combined PBM groups had significantly improved skin thickness measurements. Overall, we concluded that the combined PBM therapy successfully induced the early onset of anagen and stimulated hair growth. Conclusion These results suggest that PBM therapy regulates hair growth by activating the ERK/AKT/GSK3βsignaling pathway. Thus, multiple-wavelength radiation from devices combining radiation emitted by lowpower lasers and LEDs could be a new approach for promoting PBM-induced beneficial effects.

Background: s/Aims: Minimally invasive pancreatoduodenectomy (MIPD), such as totally laparoscopic pancreatoduodenectomy (TLPD) or robot-assisted pancreatoduodenectomy (RAPD), is increasingly performed worldwide. This study aimed to compare the perioperative outcomes of TLPD and RAPD, and compare the oncologic outcomes between MIPD and open pancreatoduodenectomy (OPD) for malignant disease. Methods: This retrospective study was conducted at two hospitals that followed similar oncological surgical principles, including the extent of resection. RAPD was performed at Seoul National University Hospital, and TLPD at Seoul National University Bundang Hospital. Patient demographics, perioperative outcomes, and oncological outcomes were analyzed. Propensity score matching (PSM) analysis was performed to compare oncologic outcomes between MIPD and OPD. Results: Between 2015 and 2020, 332 RAPD and 178 TLPD were performed. The rates of Clavian–Dindo grade ≥ 3 complications (19.3% vs. 20.2%, p = 0.816), clinically relevant postoperative pancreatic fistula (9.9% vs. 11.8%, p = 0.647), and open conversions (6.6% vs. 10.5%, p = 0.163) were comparable between the two groups. The mean operation time (341 minutes vs. 414 minutes, p < 0.001) and postoperative hospital stay were shorter in the RAPD group (11 days vs. 14 days, p = 0.034). After PSM, the 5-year overall survival rate was comparable between MIPD and OPD for overall malignant disease (58.4% vs. 55.5%, p = 0.180). Conclusions Both RAPD and TLPD are safe and feasible, and MIPD has clinical outcomes that are comparable to those of OPD. Although RAPD exhibits some advantages, its perioperative outcomes are similar to those associated with TLPD. A surgical method may be selected based on the convenience of surgical movements, medical costs, and operator experience.

Background: s/Aims: Minimally invasive pancreatoduodenectomy (MIPD), such as totally laparoscopic pancreatoduodenectomy (TLPD) or robot-assisted pancreatoduodenectomy (RAPD), is increasingly performed worldwide. This study aimed to compare the perioperative outcomes of TLPD and RAPD, and compare the oncologic outcomes between MIPD and open pancreatoduodenectomy (OPD) for malignant disease. Methods: This retrospective study was conducted at two hospitals that followed similar oncological surgical principles, including the extent of resection. RAPD was performed at Seoul National University Hospital, and TLPD at Seoul National University Bundang Hospital. Patient demographics, perioperative outcomes, and oncological outcomes were analyzed. Propensity score matching (PSM) analysis was performed to compare oncologic outcomes between MIPD and OPD. Results: Between 2015 and 2020, 332 RAPD and 178 TLPD were performed. The rates of Clavian–Dindo grade ≥ 3 complications (19.3% vs. 20.2%, p = 0.816), clinically relevant postoperative pancreatic fistula (9.9% vs. 11.8%, p = 0.647), and open conversions (6.6% vs. 10.5%, p = 0.163) were comparable between the two groups. The mean operation time (341 minutes vs. 414 minutes, p < 0.001) and postoperative hospital stay were shorter in the RAPD group (11 days vs. 14 days, p = 0.034). After PSM, the 5-year overall survival rate was comparable between MIPD and OPD for overall malignant disease (58.4% vs. 55.5%, p = 0.180). Conclusions Both RAPD and TLPD are safe and feasible, and MIPD has clinical outcomes that are comparable to those of OPD. Although RAPD exhibits some advantages, its perioperative outcomes are similar to those associated with TLPD. A surgical method may be selected based on the convenience of surgical movements, medical costs, and operator experience.

Purpose: Notable effectiveness of trastuzumab deruxtecan in patients with human epidermal growth factor receptor 2 (HER2)–low advanced breast cancer (BC) has focused pathologists’ attention. We studied the incidence and clinicopathologic characteristics of HER2-low BC, and the effects of immunohistochemistry (IHC) associated factors on HER2 IHC results. Materials and Methods: The Breast Pathology Study Group of the Korean Society of Pathologists conducted a nationwide study using real-world data on HER2 status generated between January 2022 and December 2022. Information on HER2 IHC protocols at each participating institution was also collected. Results: Total 11,416 patients from 25 institutions included in this study. Of these patients, 40.7% (range, 6.0% to 76.3%) were classified as HER2-zero, 41.7% (range, 10.5% to 69.1%) as HER2-low, and 17.5% (range, 6.7% to 34.0%) as HER2-positive. HER2-low tumors were associated with positive estrogen receptor and progesterone receptor statuses (p < 0.001 and p < 0.001, respectively). Antigen retrieval times (≥ 36 minutes vs. < 36 minutes) and antibody incubation times (≥ 12 minutes vs. < 12 minutes) affected on the frequency of HER2 IHC 1+ BC at institutions using the PATHWAY HER2 (4B5) IHC assay and BenchMark XT or Ultra staining instruments. Furthermore, discordant results between core needle biopsy and subsequent resection specimen HER2 statuses were observed in 24.1% (787/3,259) of the patients. Conclusion The overall incidence of HER2-low BC in South Korea concurs with those reported in previously published studies. Significant inter-institutional differences in HER2 IHC protocols were observed, and it may have impact on HER2-low status. Thus, we recommend standardizing HER2 IHC conditions to ensure precise patient selection for targeted therapy.

Background: and Purpose Unlike other immune-mediated neuropathies, anti-myelin-associated glycoprotein (MAG) neuropathy is often refractory to immunotherapy. It is necessary to compare the relative efficacies of various immunotherapies and develop objective biomarkers in order to optimize its clinical management. Methods: This study recruited 91 patients with high anti-MAG antibody titers from 7 tertiary hospitals in South Korea. We analyzed the baseline characteristics, therapeutic outcomes, and nerve conduction study (NCS) findings of 68 patients and excluded 23 false positive cases. Results: The rate of positive responses to treatment was highest using zanubrutinib (50%) and rituximab (36.4%), followed by corticosteroids (16.7%), immunosuppressants (9.5%), intravenous immunoglobulin (5%), and plasma exchange (0%). Disability and weakness were significantly associated with multiple NCS parameters at the time of diagnosis, especially distal compound muscle action potential (CMAP) amplitudes. Moreover, the longitudinal trajectory of the average CMAP amplitudes paralleled the clinical courses, with a 16.2 percentile decrease as an optimal cutoff for predicting a clinical exacerbation (area under the receiver operating characteristic curve=0.792). Conclusions Our study supports the use of NCS as an objective marker for estimating disease burden and tracking clinical changes in patients with anti-MAG neuropathy. We have described the beneficial effects of rituximab and a new drug, zanubrutinib, compared with conventional immunotherapies.

Background: Limited data are available on the mortality rates of patients receiving extracorporeal membrane oxygenation (ECMO) support for coronavirus disease 2019 (COVID-19). We aimed to analyze the relationship between COVID-19 and clinical outcomes for patients receiving ECMO. Methods: We retrospectively investigated patients with COVID-19 pneumonia requiring ECMO in 19 hospitals across Korea from January 1, 2020 to August 31, 2021. The primary outcome was the 90-day mortality after ECMO initiation. We performed multivariate analysis using a logistic regression model to estimate the odds ratio (OR) of 90-day mortality. Survival differences were analyzed using the Kaplan–Meier (KM) method. Results: Of 127 patients with COVID-19 pneumonia who received ECMO, 70 patients (55.1%) died within 90 days of ECMO initiation. The median age was 64 years, and 63% of patients were male. The incidence of ECMO was increased with age but was decreased after 70 years of age. However, the survival rate was decreased linearly with age. In multivariate analysis, age (OR, 1.048; 95% confidence interval [CI], 1.010–1.089; P = 0.014) and receipt of continuous renal replacement therapy (CRRT) (OR, 3.069; 95% CI, 1.312–7.180; P = 0.010) were significantly associated with an increased risk of 90-day mortality. KM curves showed significant differences in survival between groups according to age (65 years) (log-rank P = 0.021) and receipt of CRRT (log-rank P = 0.004). Conclusion Older age and receipt of CRRT were associated with higher mortality rates among patients with COVID-19 who received ECMO.