This report presents the latest statistics on the stroke population in South Korea, sourced from the Clinical Research Collaborations for Stroke in Korea-National Institute for Health (CRCS-K-NIH), a comprehensive, nationwide, multicenter stroke registry. The Korean cohort, unlike western populations, shows a male-to-female ratio of 1.5, attributed to lower risk factors in Korean women. The average ages for men and women are 67 and 73 years, respectively.Hypertension is the most common risk factor (67%), consistent with global trends, but there is a higher prevalence of diabetes (35%) and smoking (21%). The prevalence of atrial fibrillation (19%) is lower than in western populations, suggesting effective prevention strategies in the general population. A high incidence of large artery atherosclerosis (38%) is observed, likely due to prevalent intracranial arterial disease in East Asians and advanced imaging techniques.There has been a decrease in intravenous thrombolysis rates, from 12% in 2017–2019 to 10% in 2021, with no improvements in door-to-needle and door-to-puncture times, worsened by the coronavirus disease 2019 pandemic. While the use of aspirin plus clopidogrel for noncardioembolic stroke and direct oral anticoagulants for atrial fibrillation is well-established, the application of direct oral anticoagulants for non-atrial fibrillation cardioembolic strokes in the acute phase requires further research. The incidence of early neurological deterioration (13%) and the cumulative incidence of recurrent stroke at 3 months (3%) align with global figures. Favorable outcomes at 3 months (63%) are comparable internationally, yet the lack of improvement in dependency at 3 months highlights the need for advancements in acute stroke care.

Background: To date, there has been no practical guidelines for the prescription of antiepileptic drugs (AEDs) in brain tumor patients in Korea. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for AED usage in brain tumors since 2019. Methods: The Working Group was composed of 27 multidisciplinary medical experts in Korea.References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of the keywords. Results: The core contents are as follows. Prophylactic AED administration is not recommended in newly diagnosed brain tumor patients without previous seizure history. When AEDs are administered during peri/postoperative period, it may be tapered off according to the following recommendations. In seizure-naïve patients with no postoperative seizure, it is recommended to stop or reduce AED 1 week after surgery. In seizure-naïve patients with one early postoperative seizure (<1 week after surgery), it is advisable to maintain AED for at least 3 months before tapering. In seizure-naïve patients with ≥2 postoperative seizures or in patients with preoperative seizure history, it is recommended to maintain AEDs for more than 1 year. The possibility of drug interactions should be considered when selecting AEDs in brain tumor patients. Driving can be allowed in brain tumor patients when proven to be seizure-free for more than 1 year. Conclusion The KSNO suggests prescribing AEDs in patients with brain tumor based on the current guideline. This guideline will contribute to spreading evidence-based prescription of AEDs in brain tumor patients in Korea.

Background: There have been no guidelines for the management of adult patients with diffuse midline glioma (DMG), H3K27M-mutant in Korea since the 2016 revised WHO classification newly defined this disease entity. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for DMG since 2019. Methods: The Working Group was composed of 27 multidisciplinary medical experts in Korea.References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. As ‘diffuse midline glioma’ was recently defined, and there was no international guideline, trials and guidelines of ‘diffuse intrinsic pontine glioma’ or ‘brain stem glioma’ were thoroughly reviewed first. Results: The core contents are as follows. The DMG can be diagnosed when all of the following three criteria are satisfied: the presence of the H3K27M mutation, midline location, and infiltrating feature. Without identification of H3K27M mutation by diagnostic biopsy, DMG cannot be diagnosed. For the primary treatment, maximal safe resection should be considered for tumors when feasible. Radiotherapy is the primary option for tumors in case the total resection is not possible. A total dose of 54 Gy to 60 Gy with conventional fractionation prescribed at 1-2 cm plus gross tumor volume is recommended. Although no chemotherapy has proven to be effective in DMG, concurrent chemoradiotherapy (± maintenance chemotherapy) with temozolomide following WHO grade IV glioblastoma’s protocol is recommended. Conclusion The detection of H3K27M mutation is the most important diagnostic criteria for DMG. Combination of surgery (if amenable to surgery), radiotherapy, and chemotherapy based on comprehensive multidisciplinary discussion can be considered as the treatment options for DMG.

Background: To date, there has been no practical guidelines for the prescription of antiepileptic drugs (AEDs) in brain tumor patients in Korea. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for AED usage in brain tumors since 2019. Methods: The Working Group was composed of 27 multidisciplinary medical experts in Korea.References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of the keywords. Results: The core contents are as follows. Prophylactic AED administration is not recommended in newly diagnosed brain tumor patients without previous seizure history. When AEDs are administered during peri/postoperative period, it may be tapered off according to the following recommendations. In seizure-naïve patients with no postoperative seizure, it is recommended to stop or reduce AED 1 week after surgery. In seizure-naïve patients with one early postoperative seizure (<1 week after surgery), it is advisable to maintain AED for at least 3 months before tapering. In seizure-naïve patients with ≥2 postoperative seizures or in patients with preoperative seizure history, it is recommended to maintain AEDs for more than 1 year. The possibility of drug interactions should be considered when selecting AEDs in brain tumor patients. Driving can be allowed in brain tumor patients when proven to be seizure-free for more than 1 year. Conclusion The KSNO suggests prescribing AEDs in patients with brain tumor based on the current guideline. This guideline will contribute to spreading evidence-based prescription of AEDs in brain tumor patients in Korea.

Background: There have been no guidelines for the management of adult patients with diffuse midline glioma (DMG), H3K27M-mutant in Korea since the 2016 revised WHO classification newly defined this disease entity. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for DMG since 2019. Methods: The Working Group was composed of 27 multidisciplinary medical experts in Korea.References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. As ‘diffuse midline glioma’ was recently defined, and there was no international guideline, trials and guidelines of ‘diffuse intrinsic pontine glioma’ or ‘brain stem glioma’ were thoroughly reviewed first. Results: The core contents are as follows. The DMG can be diagnosed when all of the following three criteria are satisfied: the presence of the H3K27M mutation, midline location, and infiltrating feature. Without identification of H3K27M mutation by diagnostic biopsy, DMG cannot be diagnosed. For the primary treatment, maximal safe resection should be considered for tumors when feasible. Radiotherapy is the primary option for tumors in case the total resection is not possible. A total dose of 54 Gy to 60 Gy with conventional fractionation prescribed at 1-2 cm plus gross tumor volume is recommended. Although no chemotherapy has proven to be effective in DMG, concurrent chemoradiotherapy (± maintenance chemotherapy) with temozolomide following WHO grade IV glioblastoma’s protocol is recommended. Conclusion The detection of H3K27M mutation is the most important diagnostic criteria for DMG. Combination of surgery (if amenable to surgery), radiotherapy, and chemotherapy based on comprehensive multidisciplinary discussion can be considered as the treatment options for DMG.

Purpose: Alpha-fetoprotein (AFP) is a prognostic marker for hepatocellular carcinoma (HCC). We investigated the prognostic value of AFP levels in patients who achieved complete response (CR) to transarterial chemoembolization (TACE) for HCC. Materials and Methods: Between 2005 and 2018, 890 patients with HCC who achieved a CR to TACE were recruited. An AFP responder was defined as a patient who showed elevated levels of AFP (>10 ng/mL) during TACE, but showed normalization or a >50% reduction in AFP levels after achieving a CR. Results: Among the recruited patients, 569 (63.9%) with naïve HCC and 321 (36.1%) with recurrent HCC after complete resection were treated. Before TACE, 305 (34.3%) patients had multiple tumors, 219 (24.6%) had a maximal tumor size >3 cm, and 22 (2.5%) had portal vein tumor thrombosis. The median AFP level after achieving a CR was 6.36 ng/mL. After a CR, 473 (53.1%) patients experienced recurrence, and 417 (46.9%) died [median progression-free survival (PFS) and overall survival (OS) of 16.3 and 62.8 months, respectively]. High AFP levels at CR (>20 ng/mL) were independently associated with a shorter PFS [hazard ratio (HR)=1.403] and OS (HR=1.284), together with tumor multiplicity at TACE (HR=1.518 and 1.666, respectively). AFP non-responders at CR (76.2%, n=359 of 471) showed a shorter PFS (median 10.5 months vs. 15.5 months, HR=1.375) and OS (median 41.4 months vs. 61.8 months, HR=1.424) than AFP responders (all p=0.001). Conclusion High AFP levels and AFP non-responders were independently associated with poor outcomes after TACE. AFP holds clinical implications for detailed risk stratification upon achieving a CR after TACE.

Background: : The Guideline Working Group of the Korean Society for Neuro-Oncology (KSNO)conducted the nationwide questionnaire survey for diverse queries facing to treat patients with braintumor. As part III of the survey, the aim of this study is to evaluate the national patterns of clinical practicefor patients with brain metastasis and primary central nervous system lymphoma (PCNSL). Methods: : A web-based survey was sent to all members of the KSNO by email. The survey included7 questions of brain metastasis and 5 questions of PCNSL, focused on the management strategiesin specific situations. All questions were developed by consensus of the Guideline WorkingGroup. Results: " In the survey about brain metastasis, respondents preferred surgical resection withadjuvant treatment for patients with a surgically accessible single brain metastatic lesion less than 3cm in size without extracranial systemic lesions. However, most respondents considered radiosurgeryfor surgically inaccessible lesions. As the preferred treatment of multiple brain metastases according tothe number of brain lesions, respondents tended to choose radiotherapy with increasing number of lesions.Radiosurgery was mostly chosen for the brain metastases of less than or equal to 4. In the surveyabout PCNSL, a half of respondents choose high-dose methotrexate-based polychemotherapy asthe first-line induction therapy for PCNSL. The consolidation and salvage therapy showed a little variationamong respondents. For PCNSL patients with cerebrospinal fluid dissemination, intrathecal chemotherapywas most preferred. Conclusion : The survey demonstrates the prevailing clinical practice patterns for patients withbrain metastasis and PCNSL among members of the KSNO. This information provides a point of referencefor establishing a practical guideline in the management of brain metastasis and PCNSL.

Background: : The Guideline Working Group of the Korean Society for Neuro-Oncology (KSNO)conducted a nationwide questionnaire survey for diverse queries faced in the treatment of brain tumors.As part I of the survey, the aim of this study is to evaluate national patterns of clinical practiceabout antiepileptic drug (AED) and steroid usage for management of brain tumors. Methods: : A web-based survey was sent to all members of the KSNO by email. The survey included9 questions of AED usage and 5 questions of steroid usage for brain tumor patients. All questionswere developed by consensus of the Guideline Working Group. Results: : The overall response rate was 12.8% (54/423). Regarding AED usage, the majority ofrespondents (95.2%) routinely prescribed prophylactic AEDs for patients with seizure at the peri/postoperativeperiod. However, as many as 72.8% of respondents prescribed AED routinely for seizure-naïvepatients, and others prescribed AED as the case may be. The duration of AED prophylaxis showedwide variance according to the epilepsy status and the location of tumor. Levetiracetam (82.9%) wasthe most preferred AED for epilepsy prophylaxis. Regarding steroid usage, 90.5% of respondents usesteroids in perioperative period, including 34.2% of them as a routine manner. Presence of peritumoraledema (90.9%) was considered as the most important factor determining steroid usage followed bydegree of clinical symptoms (60.6%). More than half of respondents (51.2%) replied to discontinue thesteroids within a week after surgery if there are no specific medical conditions, while 7.3% preferredslow tapering up to a month after surgery. Conclusion : The survey demonstrated the prevailing practice patterns on AED and steroid usagein neuro-oncologic field among members of the KSNO. This information provides a point of referencefor establishing a practical guideline in the management of brain tumor patients.

Background: : The Guideline Working Group of the Korean Society for Neuro-Oncology (KSNO)conducted a nationwide questionnaire survey for diverse queries faced in the treatment of brain tumors.As part II of the survey, the aim of this study is to evaluate the national patterns of clinical practicefor patients with diffuse midline glioma and meningioma. Methods: : A web-based survey was sent to all members of the KSNO by email. The survey included4 questions of diffuse midline glioma and 6 questions of meningioma (including 2 case scenarios).All questions were developed by consensus of the Guideline Working Group. Results: : In the survey about diffuse midline glioma, 76% respondents performed histologicconfirmation to identify H3K27M mutation on immunohistochemical staining or sequencing methods.For treatment of diffuse midline glioma, respondents preferred concurrent chemoradiotherapy withtemozolomide (TMZ) and adjuvant TMZ (63.8%) than radiotherapy alone (34.0%). In the surveyabout meningioma, respondents prefer wait-and-see policy for the asymptomatic small meningiomawithout peritumoral edema. However, a greater number of respondents had chosen surgical resectionas the first choice for all large size meningiomas without exception, and small size meningiomaswith either peritumoral edema or eloquent location. There was no single opinion with major consensuson long-term follow-up plans for asymptomatic meningioma with observation policy. As many as68.1% of respondents answered that they would not add any adjuvant therapies for World Health Organizationgrade II meningiomas if the tumor was totally resected including dura. Conclusion : The survey demonstrates the prevailing clinical practice patterns for patients with diffusemidline glioma and meningioma among members of the KSNO. This information provides a pointof reference for establishing a practical guideline in the management of diffuse midline glioma andmeningioma.

Purpose: Although surgical resection is usually considered for a single tumor, several reports have suggested that resection can be considered for multiple tumors. The objective of this study was to determine whether resection could provide better long-term outcome for patients with multiple hepatocellular carcinomas (HCCs) within Milan criteria. Methods: A total of 276 patients with multiple HCCs within Milan criteria with liver function preserved who underwent resection, radiofrequency ablation (RFA), or transarterial chemoembolization (TACE) between 2009 and 2013 were analyzed. Propensity-score (PS) matching was conducted. Results: Five-year overall survival (OS) and recurrence-free survival (RFS) were better in the resection group than that in the RFA or TACE group. Patients who underwent resection had more preserved liver function and different tumor characteristics compared to those received RFA or TACE. With similar baseline characteristics generated in the PS model, there was no difference in 5-year OS among 3 groups (79.5% vs. 72.3% or 62.0%, P = 0.232), but the 5-year RFS was better for patients who received resection than those who received RFA or TACE (51.9% vs. 22.0% or 0.0%, P < 0.001). Although the major complication rate was slightly higher than RFA or TACE, there was no significant difference between the 3 groups before and after PS matching. Conclusion Resection was associated with better RFS than RFA or TACE and showed comparable OS in multiple HCC patients within the Milan criteria, but at a cost of slightly increased risk of complication. Resection can be considered as a first-line option if selected appropriately.