Background: Histone deacetylase 6 (HDAC6), belonging to class IIb of histone deacetylases, regulates theacetylation of the cytoplasmic protein α-tubulin. The overexpression of HDAC6 is linked to the development oftumors, and inhibiting HDAC6 is known to trigger apoptosis in multiple myeloma cells. In addition to its application in cancer treatment, bortezomib, a proteasome inhibitor, is widely used in managing multiple myeloma and has shown effectiveness in patients with both newly diagnosed and relapsed disease. However, the treatment regimen may be delayed or discontinued due to the risk of peripheral neuropathy, a significant non-hematologic side effect. Methods: Animal models of peripheral neuropathy induced by various anti-cancer drugs were established, confirming the potential of HDAC6 inhibitors as a treatment for this condition. Six- to eight-week-old male Sprague Dawley rats were utilized to create these models. Mechanical allodynia and electron microscopy served as indicators of peripheral neuropathy. The HDAC6 inhibitor CKD-011 was administered at doses of 5, 10, 20, and 40 mg/kg. Results: In an animal model of bortezomib-induced peripheral neuropathy, CKD-011, an HDAC6 inhibitor, effectively ameliorated peripheral neuropathy. Similarly, CKD-011 administration demonstrated recovery from peripheral neuropathy in models induced with oxaliplatin, paclitaxel, and cisplatin. Conclusions These findings suggest that HDAC6 inhibitors have the potential to mitigate peripheral neuropathy induced by chemotherapeutic agents.

Background: Epidermal growth factor receptor (EGFR) gene mutation testing is crucial for the administration of tyrosine kinase inhibitors to treat non–small cell lung cancer. In addition to traditional tissue-based tests, liquid biopsies using plasma are increasingly utilized, particularly for detecting T790M mutations. This study compared tissue- and plasma-based EGFR testing methods. Methods: A total of 248 patients were tested for EGFR mutations using tissue and plasma samples from 2018 to 2023 at Pusan National University Yangsan Hospital. Tissue tests were performed using PANAmutyper, and plasma tests were performed using the Cobas EGFR Mutation Test v2. Results: All 248 patients underwent tissue-based EGFR testing, and 245 (98.8%) showed positive results. Of the 408 plasma tests, 237 (58.1%) were positive. For the T790M mutation, tissue biopsies were performed 87 times in 69 patients, and 30 positive cases (38.6%) were detected. Plasma testing for the T790M mutation was conducted 333 times in 207 patients, yielding 62 positive results (18.6%). Of these, 57 (27.5%) were confirmed to have the mutation via plasma testing. Combined tissue and plasma tests for the T790M mutation were positive in nine patients (13.4%), while 17 (25.4%) were positive in tissue only and 12 (17.9%) in plasma only. This mutation was not detected in 28 patients (43.3%). Conclusions Although the tissue- and plasma-based tests showed a sensitivity of 37.3% and 32.8%, respectively, combined testing increased the detection rate to 56.7%. Thus, neither test demonstrated superiority, rather, they were complementary.

Pertussis is endemic worldwide, with epidemics occurring every 2 to 5 years despite a high vaccination coverage.After limited circulation during the coronavirus disease 2019 (COVID-19) pandemic, pertussis cases have increased rapidly worldwide since mid-late 2023, returning to pre-pandemic patterns. In Korea, 90 cases of pertussis were reported from April 2020 to May 2023, with elderly individuals aged ≥65 years accounting for 48.9%. Pertussis cases have increased sharply since June 2024, showing a nationwide epidemic, with a large increase among adolescents aged 13–15 years. As of August 2024, the national incidence rate of pertussis was estimated to be 37.75 per 100,000 population, with the highest incidence of 526.2 per 100,000 population in 13-year-olds. In Europe, during 2023–2024, an increase in pertussis incidence among infants was observed, along with large increases in 10–19-yearolds. In China, the number of reported cases of pertussis has increased rapidly since late 2023, with an age shift to older children, increase of vaccine escape, and a marked increase in the prevalence of macrolide-resistant Bordetella pertussis. The recent global resurgence of pertussis is due to decreased opportunities for boosting immunity by natural infection during the COVID-19 pandemic in combination with waning of immunity-induced pertussis vaccines.

The initial molecular cytogenetic characteristics of blasts plays a significant role in determining the treatment course of B-cell acute lymphoblastic leukemia (B-ALL).B-ALL with intrachromosomal amplification of chromosome 21 (iAMP21) has been well known to have unfavorable prognosis. Also, there are previously recognized germline mutations that increase the risk of ALL, such as trisomy 21, Down syndrome. This case report is about a 16-year-old girl who presented with lymphadenitis, purpura, and fever followed by initial lab of elevated white blood cell with blasts.She had some notable facial features, but no typical Down syndrome related one.Bone marrow biopsy and fluorescence in situ hybridization finalized the diagnosis as B-ALL with iAMP21, high-risk group. The minimal residual disease-negative complete remission was achieved after the induction chemotherapy with Korean multicenter high-risk protocol. However, abnormal karyotype was sustained in bone marrow. Microarrays with her buccal swab raised the possibility that the abnormal karyotype was not from the leukemic blasts but rather from the germline. Although she underwent scheduled chemotherapy uneventfully as slow early responder type, thrombocytopenia and abnormal karyotype persisted, leading to the diagnosis of acute myeloid leukemia. Additional chemotherapy and peripheral blood stem cell transplantation was performed which resulted in engraftment. This case highlights the discovery of a constitutional genetic aberration, which played like a silent yet critical background factor for B-ALL with iAMP21. As the number of reported cases are limited, the role of germline chromosome 21 mutation as the indicator for prognosis of B-ALL should be studied further.

Purpose: This study aimed to assess prognostic factors associated with combined hepatocellular-cholangiocarcinoma (cHCC-CCA) and to predict 5-year survival based on these factors. Materials and Methods: Patients who underwent definitive hepatectomy from 2006 to 2022 at a single institution was retrospectively analyzed. Inclusion criteria involved a pathologically confirmed diagnosis of cHCC-CCA. Results: A total of 80 patients with diagnosed cHCC-CCA were included in the analysis. The median progression-free survival was 15.6 months, while distant metastasis-free survival (DMFS), hepatic progression-free survival, and overall survival (OS) were 50.8, 21.5, and 85.1 months, respectively. In 52 cases of recurrence, intrahepatic recurrence was the most common initial recurrence (34/52), with distant metastasis in 17 cases. Factors associated with poor DMFS included tumor necrosis, lymphovascular invasion (LVI), perineural invasion, and histologic compact type. Postoperative carbohydrate antigen 19-9, tumor necrosis, LVI, and close/positive margin were associated with poor OS. LVI emerged as a key factor affecting both DMFS and OS, with a 5-year OS of 93.3% for patients without LVI compared to 35.8% with LVI. Based on these factors, a nomogram predicting 3-year and 5-year DMFS and OS was developed, demonstrating high concordance with actual survival in the cohort (Harrell C-index 0.809 for OS, 0.801 for DMFS, respectively). Conclusion The prognosis of cHCC-CCA is notably poor when combined with LVI. Given the significant impact of adverse features, accurate outcome prediction is crucial. Moreover, consideration of adjuvant therapy may be warranted for patients exhibiting poor survival and increased risk of local recurrence or distant metastasis.

Background: Histone deacetylase 6 (HDAC6), belonging to class IIb of histone deacetylases, regulates theacetylation of the cytoplasmic protein α-tubulin. The overexpression of HDAC6 is linked to the development oftumors, and inhibiting HDAC6 is known to trigger apoptosis in multiple myeloma cells. In addition to its application in cancer treatment, bortezomib, a proteasome inhibitor, is widely used in managing multiple myeloma and has shown effectiveness in patients with both newly diagnosed and relapsed disease. However, the treatment regimen may be delayed or discontinued due to the risk of peripheral neuropathy, a significant non-hematologic side effect. Methods: Animal models of peripheral neuropathy induced by various anti-cancer drugs were established, confirming the potential of HDAC6 inhibitors as a treatment for this condition. Six- to eight-week-old male Sprague Dawley rats were utilized to create these models. Mechanical allodynia and electron microscopy served as indicators of peripheral neuropathy. The HDAC6 inhibitor CKD-011 was administered at doses of 5, 10, 20, and 40 mg/kg. Results: In an animal model of bortezomib-induced peripheral neuropathy, CKD-011, an HDAC6 inhibitor, effectively ameliorated peripheral neuropathy. Similarly, CKD-011 administration demonstrated recovery from peripheral neuropathy in models induced with oxaliplatin, paclitaxel, and cisplatin. Conclusions These findings suggest that HDAC6 inhibitors have the potential to mitigate peripheral neuropathy induced by chemotherapeutic agents.

Background: Histone deacetylase 6 (HDAC6), belonging to class IIb of histone deacetylases, regulates theacetylation of the cytoplasmic protein α-tubulin. The overexpression of HDAC6 is linked to the development oftumors, and inhibiting HDAC6 is known to trigger apoptosis in multiple myeloma cells. In addition to its application in cancer treatment, bortezomib, a proteasome inhibitor, is widely used in managing multiple myeloma and has shown effectiveness in patients with both newly diagnosed and relapsed disease. However, the treatment regimen may be delayed or discontinued due to the risk of peripheral neuropathy, a significant non-hematologic side effect. Methods: Animal models of peripheral neuropathy induced by various anti-cancer drugs were established, confirming the potential of HDAC6 inhibitors as a treatment for this condition. Six- to eight-week-old male Sprague Dawley rats were utilized to create these models. Mechanical allodynia and electron microscopy served as indicators of peripheral neuropathy. The HDAC6 inhibitor CKD-011 was administered at doses of 5, 10, 20, and 40 mg/kg. Results: In an animal model of bortezomib-induced peripheral neuropathy, CKD-011, an HDAC6 inhibitor, effectively ameliorated peripheral neuropathy. Similarly, CKD-011 administration demonstrated recovery from peripheral neuropathy in models induced with oxaliplatin, paclitaxel, and cisplatin. Conclusions These findings suggest that HDAC6 inhibitors have the potential to mitigate peripheral neuropathy induced by chemotherapeutic agents.

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.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.