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: Various molecular methods are used to rapidly detect gastrointestinal pathogens, highlighting the importance of understanding the performance of the associated kits in detail. We comprehensively assessed the performance of Kogene PowerChek multiplex real-time PCR kits (PowerChek Bacterial/Viral Kits) with the FilmArray GI Panel. Methods: Residual stool specimens (N = 246), initially tested utilizing the FilmArray GI Panel (May 2023–Jan 2024), were reanalyzed using PowerChek Bacterial/Viral Kits. Discrepancies were resolved by performing additional molecular assays and reviewing culture results when available. True positives (TPs)/true negatives were defined by concordant results in at least two assays. We determined cycle threshold (Ct)/crossing point (Cp) distributions between the TP and false positive (FP) groups and analyzed melting curves for the FilmArray GI Panel FPs. Results: The positive-percent agreement (PPA) of the PowerChek Bacterial/Viral Kits was 50–100%, with lower values for Salmonella spp., rotavirus, and astrovirus, whereas the FilmArray GI Panel showed 100% PPA across all targets. Both platforms demonstrated > 99% negative-percent agreement, except for enteropathogenic Escherichia coli (EPEC) and adenovirus (PowerChek Bacterial/Viral Kits) or EPEC, enteroaggregative E. coli, norovirus, and Salmonella spp. (FilmArray GI Panel). The FPs showed higher Ct/Cp values with both kits, and these values were significantly higher for adenovirus (PowerChek Viral Kit), EPEC, and norovirus (FilmArray GI Panel). Melting curve analysis of four norovirus FPs (FilmArray GI Panel) revealed atypical patterns in three cases. Conclusions The FilmArray GI Panel demonstrated higher sensitivity than the PowerChek Kits. For norovirus, melting curve analysis will help avoid FPs.

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.