Imaging-Based Versus Pathologic Survival Stratifications of Diffuse Glioma According to the 2021 WHO Classification System

Objective@#Imaging-based survival stratification of patients with gliomas is important for their management, and the 2021 WHO classification system must be clinically tested. The aim of this study was to compare integrative imaging- and pathology-based methods for survival stratification of patients with diffuse glioma. @*Materials and Methods@#This study included diffuse glioma cases from The Cancer Genome Atlas (training set: 141 patients) and Asan Medical Center (validation set: 131 patients). Two neuroradiologists analyzed presurgical CT and MRI to assign gliomas to five imaging-based risk subgroups (1 to 5) according to well-known imaging phenotypes (e.g., T2/FLAIR mismatch) and recategorized them into three imaging-based risk groups, according to the 2021 WHO classification: group 1 (corresponding to risk subgroup 1, indicating oligodendroglioma, isocitrate dehydrogenase [IDH]-mutant, and 1p19q-codeleted), group 2 (risk subgroups 2 and 3, indicating astrocytoma, IDH-mutant), and group 3 (risk subgroups 4 and 5, indicating glioblastoma, IDHwt). The progression-free survival (PFS) and overall survival (OS) were estimated for each imaging risk group, subgroup, and pathological diagnosis. Time-dependent area-under-the receiver operating characteristic analysis (AUC) was used to compare the performance between imaging-based and pathology-based survival model. @*Results@#Both OS and PFS were stratified according to the five imaging-based risk subgroups (P < 0.001) and three imagingbased risk groups (P < 0.001). The three imaging-based groups showed high performance in predicting PFS at one-year (AUC, 0.787) and five-years (AUC, 0.823), which was similar to that of the pathology-based prediction of PFS (AUC of 0.785 and 0.837). Combined with clinical predictors, the performance of the imaging-based survival model for 1- and 3-year PFS (AUC 0.813 and 0.921) was similar to that of the pathology-based survival model (AUC 0.839 and 0.889). @*Conclusion@#Imaging-based survival stratification according to the 2021 WHO classification demonstrated a performance similar to that of pathology-based survival stratification, especially in predicting PFS.

Clinical and Genetic Features of Korean Inherited Arrhythmia Probands

Background and Objectives@#Inherited arrhythmia (IA) is a more common cause of sudden cardiac death in Asian population, but little is known about the genetic background of Asian IA probands. We aimed to investigate the clinical characteristics and analyze the genetic underpinnings of IA in a Korean cohort. @*Methods@#This study was conducted in a multicenter cohort of the Korean IA Registry from 2014 to 2017. Genetic testing was performed using a next-generation sequencing panel including 174 causative genes of cardiovascular disease. @*Results@#Among the 265 IA probands, idiopathic ventricular fibrillation (IVF) and Brugada Syndrome (BrS) was the most prevalent diseases (96 and 95 cases respectively), followed by long QT syndrome (LQTS, n=54). Two-hundred-sixteen probands underwent genetic testing, and 69 probands (31.9%) were detected with genetic variant, with yield of pathogenic or likely pathogenic variant as 6.4%. Left ventricular ejection fraction was significantly lower in genotype positive probands (54.7±11.3 vs. 59.3±9.2%, p=0.005). IVF probands showed highest yield of positive genotype (54.0%), followed by LQTS (23.8%), and BrS (19.5%). @*Conclusions@#There were significant differences in clinical characteristics and genetic yields among BrS, LQTS, and IVF. Genetic testing did not provide better yield for BrS and LQTS. On the other hand, in IVF, genetic testing using multiple gene panel might enable the molecular diagnosis of concealed genotype, which may alter future clinical diagnosis and management strategies.

The Clinicopathological Features of Mixed Carcinoma in 7,215Patients with Gastric Cancer in a Tertiary Hospital in South Korea

Background/Aims@#There are few reports regarding mixed carcinoma, defined as a mixture of glandular and poorly cohesive components, in patients with gastric cancer (GC). The aim of this study was to evaluate the proportion and characteristics of mixed carcinoma in GC patients. @*Methods@#A total of 7,215 patients diagnosed with GC at Seoul National University Bundang Hospital were enrolled from March 2011 to February 2020. GC was divided into four groups (wellmoderately differentiated GC, poorly differentiated GC, poorly cohesive carcinoma, and mixed carcinoma). The proportion of each GC type and the clinicopathological features were analyzed and divided into early GC and advanced GC. @*Results@#The proportion of mixed carcinoma was 10.9% (n=787). In early GC, submucosal invasion was the most common in poorly differentiated (53.7%), and mixed carcinoma ranked second (41.1%). Mixed carcinoma showed the highest proportion of lymph node metastasis in early GC (23.0%) and advanced GC (78.3%). In advanced GC, the rate of distant metastasis was 3.6% and 3.9% in well-moderately differentiated GC and mixed carcinoma, respectively, lower than that in poorly differentiated GC (6.4%) and poorly cohesive carcinoma (5.7%), without statistical significance. @*Conclusions@#Mixed carcinoma was associated with lymph node metastasis compared to other histological GC subtypes. And it showed relatively common submucosal invasion in early GC, but the rates of venous invasion and distant metastasis were lower in advanced GC. Further research is needed to uncover the mechanism underlying these characteristics of mixed carcinoma (Trial registration number: NCT04973631).

Tumor Habitat Analysis Using Longitudinal Physiological MRI to Predict Tumor Recurrence After Stereotactic Radiosurgery for Brain Metastasis

Objective@#It is difficult to predict the treatment response of tissue after stereotactic radiosurgery (SRS) because radiation necrosis (RN) and tumor recurrence can coexist. Our study aimed to predict tumor recurrence, including the recurrence site, after SRS of brain metastasis by performing a longitudinal tumor habitat analysis. @*Materials and Methods@#Two consecutive multiparametric MRI examinations were performed for 83 adults (mean age, 59.0 years; range, 27–82 years; 44 male and 39 female) with 103 SRS-treated brain metastases. Tumor habitats based on contrastenhanced T1- and T2-weighted images (structural habitats) and those based on the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) images (physiological habitats) were defined using k-means voxel-wise clustering. The reference standard was based on the pathology or Response Assessment in Neuro-Oncologycriteria for brain metastases (RANO-BM). The association between parameters of single-time or longitudinal tumor habitat and the time to recurrence and the site of recurrence were evaluated using the Cox proportional hazards regression analysis and Dice similarity coefficient, respectively. @*Results@#The mean interval between the two MRI examinations was 99 days. The longitudinal analysis showed that an increase in the hypovascular cellular habitat (low ADC and low CBV) was associated with the risk of recurrence (hazard ratio [HR], 2.68; 95% confidence interval [CI], 1.46–4.91; P = 0.001). During the single-time analysis, a solid low-enhancing habitat (low T2 and low contrast-enhanced T1 signal) was associated with the risk of recurrence (HR, 1.54; 95% CI, 1.01–2.35; P= 0.045). A hypovascular cellular habitat was indicative of the future recurrence site (Dice similarity coefficient = 0.423). @*Conclusion@#After SRS of brain metastases, an increased hypovascular cellular habitat observed using a longitudinal MRI analysis was associated with the risk of recurrence (i.e., treatment resistance) and was indicative of recurrence site. A tumor habitat analysis may help guide future treatments for patients with brain metastases.

Impact of Body Mass Index on Survival Depending on Sex in 14,688 Patients with Gastric Cancer in a Tertiary Hospital in South Korea

Background/Aims@#The incidence and prognosis of gastric cancer (GC) shows sex difference.This study aimed to evaluate the effect of body mass index (BMI) on GC survival depending on sex. @*Methods@#The sex, age, location, histology, TNM stages, BMI, and survival were analyzed in GC patients from May 2003 to February 2020 at the Seoul National University Bundang Hospital. @*Results@#Among 14,688 patients, there were twice as many males (66.6%) as females (33.4%).However, under age 40 years, females (8.6%) were more prevalent than males (3.1%). Cardia GC in males showed a U-shaped distribution for underweight (9.6%), normal (6.4%), overweight (6.1%), obesity (5.6%), and severe obesity (9.3%) but not in females (p=0.003). Females showed decreased proportion of diffuse-type GC regarding BMI (underweight [59.9%], normal [56.8%], overweight [49.5%], obesity [44.8%], and severe obesity [41.7%]), but males did not (p<0.001). Both sexes had the worst prognosis in the underweight group (p<0.001), and the higher BMI, the better prognosis in males, but not females. Sex differences in prognosis according to BMI tended to be more prominent in males than in females in subgroup analysis of TNM stages I, II, and III and the operative treatment group. @*Conclusions@#GC-specific survival was affected by BMI in a sex-dependent manner. These differences may be related to genetic, and environmental, hormonal factors; body composition; and muscle mass (Trial registration number: NCT04973631).

Kidney Transplantation From Deceased Donors With Bloodstream Infection: A Multicenter Retrospective Study

Background@#The use of organs from donors with infection is limited because of the possibility of transmission. We aimed to investigate the transmission after deceased donor transplantation with bloodstream infection (BSI). @*Methods@#A retrospective study of patients undergoing kidney or pancreas transplantation at five tertiary centers in Korea from January 2009 and November 2019 was performed. We analyzed the outcomes after transplantation from deceased donors with BSI. @*Results@#Eighty-six recipients received transplantation from 69 donors with BSI. The most common isolated pathogens from donors were Gram-positive bacteria (72.0%), followed by Gram-negative bacteria (22.7%), and fungi (5.3%). Appropriate antimicrobial agents were used in 47.8% of donors before transplantation. Transmission occurred only in 1 of 83 recipients (1.2%) from bacteremic donors and 1 of 6 recipients (16.7%) from fungemic donors. One-year patient and graft survival was 97.5%and 96.3%, respectively. There was no significant difference in graft and patient survival between patients who received organs from infected donors and noninfected donors. @*Conclusion@#Using organs from donors with bacteremia seems to be a safe option with low transmission risk. The overall prognosis of using organs from donors with BSI is favorable.

Four-Tier Pathologic Tumor Regression Grading System Predicts the Clinical Outcome in Patients Who Undergo Surgical Resection for Locally Advanced Pancreatic Cancer after Neoadjuvant Chemotherapy

Background/Aims@#Neoadjuvant chemotherapy is increasingly utilized in patients with borderline or locally advanced pancreatic cancer (LAPC). However, the pathologic evaluation of tumor regression is not routinely performed or well established. We aimed to evaluate the prognostic value of three tumor regression grading systems frequently used in LAPC and to determine the correlation between pathologic and clinical response. @*Methods@#We included a total of 38 patients with LAPC who were treated with neoadjuvant chemotherapy and subsequent resection. Pathologic tumor regression was graded based on the College of American Pathologists (CAP), Evans, and MD Anderson grading systems. @*Results@#One out of 38 patients (2.6%) achieved a pathologic complete response. Unlike other grading systems (Evans, p=0.063; MD Anderson, p=0.110), the CAP grading system was a significant prognostic factor for overall survival (p=0.043). Pathologic N stage (p=0.023), margin status (p=0.044), and radiologic response (p=0.016) correlated with overall survival. In the multivariate analysis, CAP 3 was an independent predictor of shorter overall survival (p=0.026). The CAP grading system correlated with the radiologic response (p=0.007) but not the carbohydrate antigen 19-9 level (p=0.333). @*Conclusions@#The four-tier CAP pathologic tumor regression grading system predicted the clinical outcome in LAPC patients who underwent resection after neoadjuvant chemotherapy. Therefore, a more comprehensive pathologic evaluation is warranted in these patients.

Extraventricular Neurocytoma: Clinical Investigation of Heterogenous Prognosis

Background@#Extraventricular neurocytoma (EVN) is an extremely rare neuronal neoplasm that arises outside the ventricle. The clinical implication of the heterogenous prognosis of this rare tumor has not yet been clarified. Herein, we analyzed our institutional series of EVN. @*Methods@#A total of eight consecutive cases were enrolled and investigated. The prognosis of EVN was analyzed and compared to that of central neurocytoma (CN). @*Results@#There were two male and six female patients, and the median age was 36.5 years. The median tumor size was 38 mm, and the most common location of the tumor was the frontal lobe (3, 37.5%), followed by the parietal and temporal lobes. In brain imaging, four (50%) tumors showed peritumoral edema and three (37.5%) tumors showed calcification. All patients underwent gross total resection, and two (25%) underwent adjuvant radiotherapy. The 5-year overall survival (OS) was 55.6%, and the 2-year progression-free survival (PFS) was 42.9%. The OS and PFS of EVN were poor compared to those of CN. Although EVN is a single disease entity, individual patients showed varying prognosis. One patient showed no recurrence during the 7-year follow-up period; however, another patient had a recurrence 4 months after surgery and died 2 years later. @*Conclusion@#EVN may be a heterogenous disease entity. Additional cases with long-term followup are needed to develop optimal management protocols.

Hepatocellular carcinoma and cancer-related mortality after kidney transplantation with rituximab treatment

Purpose@#There are increased therapeutic usages of rituximab in kidney transplantation (KT). However, few studies have evaluated the effect of rituximab on cancer development following KT. This study aimed to evaluate the effect of rituximab on the cancer occurrence and mortality rate according to each type of cancer. @*Methods@#Five thousand consecutive recipients who underwent KT at our center were divided into era1 (1990–2007) and era2-rit– (2008–2018), and era2-rit+ (2008–2018) groups. The era2-rit+ group included patients who received single-dose rituximab (200–500 mg) as a desensitization treatment 1–2 weeks before KT. @*Results@#The 5-year incidence rates of malignant tumors after KT were 3.1%, 4.3%, and 3.5% in the era1, era2-rit–, and era2-rit+ group, respectively. The overall incidence rate of cancer after transplantation among the 3 study groups showed no significant difference (P = 0.340). The overall cancer-related mortality rate was 17.1% (53 of 310). Hepatocellular carcinoma (HCC) had the highest mortality rate (61.5%) and relative risk of cancer-related death (hazard ratio, 8.29; 95% confidence interval, 2.40–28.69; P = 0.001). However, we found no significant association between rituximab and the incidence of any malignancy. @*Conclusion@#Our results suggest that single-dose rituximab for desensitization may not increase the risk of malignant disease or cancer-related mortality in KT recipients. HCC was associated with the highest risk of cancer-related mortality in an endemic area of HBV infection.

Lumbar Interbody Fusion and Osteobiologics for Lumbar Fusion

Lumbar interbody fusion (LIF) is an excellent treatment option for a number of lumbar diseases. LIF can be performed through posterior, transforaminal, anterior, and lateral or oblique approaches. Each technique has its own pearls and pitfalls. Through LIF, segmental stabilization, neural decompression, and deformity correction can be achieved. Minimally invasive surgery has recently gained popularity and each LIF procedure can be performed using minimally invasive techniques to reduce surgery-related complications and improve early postoperative recovery. Despite advances in surgical technology, surgery-related complications after LIF, such as pseudoarthrosis, have not yet been overcome. Although autogenous iliac crest bone graft is the gold standard for spinal fusion, other bone substitutes are available to enhance fusion rate and reduce complications associated with bone harvest. This article reviews the surgical procedures and characteristics of each LIF and the osteobiologics utilized in LIF based on the available evidence.

Survival Outcomes and Predictors for Recurrence of Surgically Treated Brain Metastasis From Non-Small Cell Lung Cancer

Background@#There are numerous factors to consider in deciding whether to undergo surgical treatment for brain metastasis from lung cancer. Herein, we aimed to analyze the survival outcome and predictors of recurrence of surgically treated brain metastasis from non-small cell lung cancer (NSCLC). @*Methods@#A total of 197 patients with brain metastasis from NSCLC who underwent microsurgery were included in this study. @*Results@#A total of 114 (57.9%) male and 83 (42.1%) female patients with a median age of 59 years (range, 27–79) was included in this study. The median follow-up period was 22.7 (range, 1–126) months. The 1-year and 2-year overall survival (OS) rates of patients with brain metastasis secondary to NSCLC were 59% and 43%, respectively. The 6-month and 1-year progression-free survival (PFS) rates of local recurrence were 80% and 73%, respectively, whereas those of distant recurrence were 84% and 63%, respectively. En-bloc resection of tumor resulted in better PFS for local recurrence (1-year PFS: 79% vs. 62%, p=0.02). Ventricular opening and direct contact between the tumor and the subarachnoid space were not associated with distal recurrence and leptomeningeal seeding. The difference in PFS of local recurrence according to adjuvant resection bed irradiation was not significant. Moreover, postoperative whole-brain irradiation did not show a significant difference in PFS of distant recurrence. In multivariate analysis, only En-bloc resection was a favorable prognostic factor for local recurrence. Contrastingly, multiple metastasis was a poor prognostic factor for distant recurrence. @*Conclusion@#En-bloc resection may reduce local recurrence after surgical resection. Ventricular opening and contact between the tumor and subarachnoid space did not show a statistically significant result for distant recurrence and leptomeningeal seeding. Multiple metastasis was only meaningful factor for distant recurrence.

Relationship between Sagittal Alignment and Anterior Bony Resorption of Cervical Vertebral Body in Patients with Ankylosing Spondylitis

Methods@#This retrospective study included 238 patients with AS who underwent surgical correction for thoracolumbar kyphosis. Of these, 80 patients with complete subaxial ankylosis were selected and divided into two groups: groups 1 (consisting of 28 patients with anterior bony resorption) and 2 (consisting of 52 patients without anterior resorption). Cervical sagittal parameters were analyzed and compared between the two groups. @*Results@#The average lateral diameter measured in patients with C5 anterior resorption was 84.2%±7.8% (62.4%–96.8%). Cervical lordosis was 8.7°±13.4° and 10.9°±11.5° in groups 1 and 2 (p=0.556), respectively. No significant differences were noted between the two groups on spinopelvic alignment in the T1 slope (52.2°±11.1° and 53.3°±9.9° in groups 1 and 2, respectively; p=0.742), C2–C7 sagittal vertical axis (SVA; 6.2±1.7 cm and 6.2±1.8 cm in groups 1 and 2, respectively; p=0.978), C7 SVA (14.3±4.9 cm and 14.6±6.2 cm in groups 1 and 2, respectively; p=0.823), or T1 pelvic angle (27.1°±8.9° and 31.6°±11.2° in groups 1 and 2, respectively; p=0.382). Correlation analyses were significant between the extent of anterior resorption and sagittal parameters, C2–C7 lordosis (R2=−0.428, p=0.021), and T1–T4 kyphosis (R2=−0.375, p=0.045). @*Conclusions@#Anterior bony resorption could develop by stress concentration. However, the development was not related to the sagittal alignment. The particular segments involved in developing anterior resorption varied, possibly because of their dependence on the preceding pattern of ankylosis.

Predicting stage ypT0–1N0 for nonradical management in patients with middle or low rectal cancer who undergo neoadjuvant chemoradiotherapy: a retrospective cohort study

Purpose@#It is important to discover predictive factors that can identify rectal cancer patients who will respond well to neoadjuvant concurrent chemoradiotherapy (CCRT) to develop management strategies, preserve sphincter and avoid overtreatment. This study explored clinical factors that would predict the adequacy of nonradical management after CCRT in patients with middle or low rectal cancer. @*Methods@#We retrospectively evaluated 447 patients with middle or low rectal cancer who were treated with curative surgery after neoadjuvant CCRT between January 2010 and December 2019. The good response group comprised patients with stages ypT0–1N0 on resection after CCRT; the remaining patients were included in the poor response group. @*Results@#Of 447 patients (mean age, 60.37 ± 11.85 years), 108 (24.2%) had ypT0–1N0 (71.3% with ypT0N0, 4.6% with ypTisN0, and 24.1% with ypT1N0). Overall, 19 patients with cT1–2 (50.0% vs. 21.8% with cT3–4, P < 0.001), 22 with well-differentiated tumors (51.2% vs. 21.3% with moderately/poorly differentiated tumors, P < 0.001), 16 with fungating tumors (47.1% vs.22.3% with other types, P = 0.001), and 66 with anterior/posterior circumference direction (28.9% vs. 19.2% with lateral/ encircling direction, P = 0.016) had stage ypT0–1N0. On multivariable analysis, cT1–2 (P = 0.021) and well-differentiated tumor (P = 0.001) were independent predictors of ypT0–1N0. Fungating tumors were not significantly associated with ypT0– 1N0 (P = 0.054). @*Conclusion@#Stage cT1–2 and well differentiation are predictors of ypT0–1N0, while fungating tumors could be considered clinically meaningful, possibly identifying candidates for nonradical treatment post-CCRT.

Electrical Remodeling of Left Atrium Is a Better Predictor for Recurrence Than Structural Remodeling in Atrial Fibrillation Patients Undergoing Radiofrequency Catheter Ablation

Background and Objectives@#Recurrence rates after radiofrequency catheter ablation (RFCA) in atrial fibrillation (AF) patients are not low especially in non-paroxysmal AF. The diameter of left atrium (LA) has been widely used to predict the recurrence after RFCA for decades. However, LA diameter represents structural remodeling of LA and does not reflect electrical remodeling. We aimed to determine the predictive value of electrical remodeling of LA which is represented by the amount of low voltage zone (LVZ). @*Methods@#We performed a retrospective cohort analysis of AF patients who underwent de novo RFCA in a single-center. @*Results@#A total of 3,120 AF patients with de novo RFCA were analyzed. Among these patients, 537 patients underwent an electroanatomic mapping with bipolar voltage measurement of LA.The diameter of LA and flow velocity of LA appendage (LAA) differed significantly according to quartile group of LVZ area and percentage: patients with high LVZ had large LA diameter and low LAA flow velocity (p<0.001). Freedom from late recurrence (LR) was significantly lower in patients with high LVZ area and percentage (p<0.001). The diameter and surface area of LA had area under curve (AUC) of 0.592 and 0.593, respectively (p=0.002 for both). The predictive value of LVZ area (AUC, 0.676) and percentage (AUC, 0.671) were both superior compared with LA diameter (p=0.011 and 0.027 for each comparison). @*Conclusions@#In conclusion, LVZ can predict freedom from LR after RFCA in AF patients. Predictive value was higher in parameters reflecting electrical rather than structural remodeling of LA.

Clinical Implications of the Mitotic Index as a Predictive Factor for Malignant Transformation of Atypical Meningiomas

Objective@#: Intracranial atypical meningiomas have a poor prognosis and high rates of recurrence. Moreover, up to one-third of the recurrences undergo high-grade transformation into malignant meningiomas. We aimed to investigate the clinical factors that can predict the propensity of malignant transformation from atypical to anaplastic meningiomas. @*Methods@#: Between 2001 and 2018, all patients with atypical meningioma, in whom the tumors had undergone malignant transformation to anaplastic meningioma, were included. The patients’ medical records documenting the diagnosis of atypical meningioma prior to malignant transformation were reviewed to identify the predictors of transformation. The control group comprised 56 patients with atypical meningiomas who were first diagnosed between January 2017 and December 2018 and had no malignant transformation. @*Results@#: Nine patients in whom the atypical meningiomas underwent malignant transformation were included. The median time interval from diagnosis of atypical meningioma to malignant transformation was 19 months (range, 7–78). The study group showed a significant difference in heterogeneous enhancement (77.8% vs. 33.9%), bone invasion (55.6% vs. 12.5%), mitotic index (MI; 14.8±4.9 vs. 3.5±3.9), and Ki-67 index (20.7±13.9 vs. 9.5±7.1) compared with the control group. In multivariate analysis, increased MI (odds ratio, 1.436; 95% confidence interval, 1.127–1.900; p=0.004) was the only significant factor for predicting malignant transformation. @*Conclusion@#: An increased MI within atypical meningiomas might be used as a predictor of malignant transformation. Tumors at high risk for malignant transformation might require more attentive surveillance and management than other atypical meningiomas.

Unstable Pathologic Vertebral Fractures in Multiple Myeloma : Propensity Score Matched Cohort Study between Reconstructive Surgery with Adjuvant Radiotherapy and Radiotherapy Alone

Objective@#: Although radiotherapy (RT) is recommended for multiple myeloma (MM) involving spine, the treatment of choice between reconstructive surgery with RT and RT alone for pathologic vertebral fractures (PVFs) associated with structural instability or neurologic compromises remains controversial. The purpose of this study was to evaluate the clinical efficacies of reconstructive surgery with adjuvant RT for treatment of MM with PVFs by comparing with matched cohorts treated with RT alone. @*Methods@#: Twenty-eight patients underwent reconstructive surgery followed by RT between 2008 and 2015 in a single institution, for management of PVFs associated with structural instability of the spine and/or neurologic compromises (group I). Twentyeight patients were treated with RT alone (group II) after propensity score matching in a 1-to-1 format based on instability of the spine, as well as age and performance. Clinical outcomes including the overall survival rates, duration of independent ambulation, neurological status, and numeric rating scale (NRS) for back pain were compared. @*Results@#: Clinical and radiological features before treatment were similar in both groups. The median survival period was similar between the two groups. However, the mean duration of independent ambulation was significantly longer in group I (88.8 months; 95% confidence interval [CI], 66.0–111.5) than in group II (39.4 months; 95% CI, 25.2–53.6) (log rank test; p=0.022). Deterioration of Frankel grade (21.4% vs. 60.7%, p=0.024) and NRS for back pain (2.7±2.2 vs. 5.0±2.7, p=0.000) at the last follow-up were higher in the group II. Treatment-related complications were similar in both groups. @*Conclusion@#: In patients with unstable PVFs due to MM, reconstructive surgery may yield superior clinical outcomes compared with RT alone in maintaining independent ambulation and neurological status, as well as pain control despite similar median survival and complications.

A prospective, observational study of rivaroxaban for stroke prevention in atrial fibrillation: the XANAP Korea

Background/Aims@#Atrial fibrillation (AF)-related stroke accounts for 20% of ischemic strokes. Rivaroxaban use in AF patients for preventing stroke and systemic embolism was approved in 2013 in Korea. This study was to investigate the safety and effectiveness of rivaroxaban use in Korean patients with non-valvular AF in a real-world setting. @*Methods@#This was an analysis of the Korean patients in Xarelto for Prevention of Stroke in Patients with Atrial Fibrillation in Asia-Pacific (XANAP), which was a prospective, observational cohort study including patients with non-valvular AF starting rivaroxaban treatment to prevent stroke or non-central nervous system systemic embolism (non-CNS SE), conducted in 10 Asian countries. @*Results@#A total of 844 patients were enrolled in the Korean portion of the XANAP study. In XANAP Korea, the mean age was 70.1 years and 62.6% were males. The mean CHADS2 score was 2.5 and the mean CHA2DS2-VASc score was 3.8. 47% of the patients had experienced prior stroke or non-CNS SE or transient ischemic attack. 73.6% of the patients had CHADS2 score ≥ 2. Incidence proportions of 0.8% of the patients (1.1 per 100 patient-years) developed adjudicated treatment-emergent major bleeding. Death was observed in 1.2% of the patients. The incidence of non-major bleeding as well as thromboembolic event were 8.4% (11.6 per 100 patient-years) and 1.5% (2.0 per 100 patient-years), respectively. @*Conclusions@#This study reaffirmed the consistent safety profile of rivaroxaban. We found consistent results with overall XANAP population for rivaroxaban in terms of safety in non-valvular AF patients for the prevention of stroke and non-CNS SE.

Evaluation of Left Atrial Appendage Isolation Using Cardiac MRI after Catheter Ablation of Atrial Fibrillation: Paradox of Appendage Reservoir

Objective@#To assess the effect of left atrial appendage (LAA) isolation on LAA emptying and left atrial (LA) function using cardiac MRI in patients who underwent successful catheter ablation of atrial fibrillation (AF). @*Materials and Methods@#This retrospective study included 84 patients (mean age, 59 ± 10 years; 67 males) who underwent cardiac MRI after successful catheter ablation of AF. According to the electrical activity of LAA after catheter ablation, patients showed either LAA isolation or LAA normal activity. The LAA emptying phase (LAA-EP, in the systolic phase [SP] or diastolic phase), LAA emptying flux (LAA-EF, mL/s), and LA ejection fraction (LAEF, %) were evaluated by cardiac MRI. @*Results@#Of the 84 patients, 61 (73%) and 23 (27%) patients showed LAA normal activity and LAA isolation, respectively.Incidence of LAA emptying in SP was significantly higher in LAA isolation (91% vs. 0%, p < 0.001) than in LAA normal activation. LAA-EF was significantly lower in LAA isolation (40.1 ± 16.2 mL/s vs. 80.2 ± 25.1 mL/s, pp < 0.001) than in LAA normal activity. Furthermore, LAEF was significantly lower in LAA isolation (23.7% ± 11.2% vs. 31.1% ± 16.6%, p = 0.04) than in LAA normal activity. Multivariate analysis demonstrated that the LAA-EP was independent from LAEF (p = 0.01). @*Conclusion@#LAA emptying in SP may be a critical characteristic of LAA isolation, and it may adversely affect the LAEF after catheter ablation of AF.

The 10-Year Trend of Out-of-hospital Cardiac Arrests: a Korean Nationwide Population-Based Study

Background and Objectives@#It is crucial to understand the exact public health burden of out-of-hospital cardiac arrest (OHCA) cases; this is presently unknown since sufficient episodes are not reported in registry studies. We aimed to evaluate the epidemiologic features and outcomes of non-traumatic OHCA. @*Methods@#During January 2008 to December 2017, we enrolled 387,665 patients who had been assigned a code for sudden cardiac arrest or had undergone cardiopulmonary resuscitation in the emergency room using the Korean National Health Insurance Service database. Those whose arrest was of non-cardiac origin were excluded. @*Results@#The incidence of OHCA per 100,000 patients increased steadily from 48.2 in 2008 to, 53.8 in 2011, 60.1 in 2014, and 66.7 in 2017, with a 1-year survival rate of 8.2%. Age and sex-adjusted mortality rates showed a decreasing trend. The hazard ratio was 1.0015 in 2009, 0.9865 in 2012, 0.9769 in 2015, and 0.9629 in 2017 (p for trend <0.0001), with coronary artery disease-related OHCA accounting for 59.8% of the total. Subgroups with coronary artery disease-related OHCA were more likely to be older and have a higher prevalence of all related comorbidities, excluding malignancy, than those with non-coronary artery disease-related OHCA. @*Conclusions@#This nationwide population-based study showed that the incidence of OHCA in Korea had increased during the last decade. The post OHCA 1-year mortality rate showed a poor outcome but improved gradually.

Multi-Layer Onlay Graft Using Hydroxyapatite Cement Placement without Cerebrospinal Fluid Diversion for Endoscopic Skull Base Reconstruction

Objective@#: The skull base reconstruction step, which prevents cerebrospinal fluid (CSF) leakage, is one of the most challenging steps in endoscopic skull base surgery (ESS). The purpose of this study was to assess the outcomes and complications of a reconstruction technique for immediate CSF leakage repair using multiple onlay grafts following ESS. @*Methods@#: A total of 230 consecutive patients who underwent skull base reconstruction using multiple onlay grafts with fibrin sealant patch (FSP), hydroxyapatite cement (HAC), and pedicled nasoseptal flap (PNF) for high-flow CSF leakage following ESS at three institutions were enrolled. We retrospectively reviewed the medical and radiological records to analyze the preoperative features and postoperative results. @*Results@#: The diagnoses included craniopharyngioma (46.8%), meningioma (34.0%), pituitary adenoma (5.3%), chordoma (1.6%), Rathke’s cleft cyst (1.1%) and others (n=21, 11.2%). The trans-planum/tuberculum approach (94.3%) was the most commonly adapted surgical method, followed by the trans-sellar and transclival approaches. The third ventricle was opened in 78 patients (41.5%). Lumbar CSF drainage was not performed postoperatively in any of the patients. Postoperative CSF leakage occurred in four patients (1.7%) due to technical mistakes and were repaired with the same technique. However, postoperative meningitis occurred in 13.5% (n=31) of the patients, but no microorganisms were identified. The median latency to the diagnosis of meningitis was 8 days (range, 2–38). CSF leakage was the unique risk factor for postoperative meningitis (p<0.001). @*Conclusion@#: The use of multiple onlay grafts with FSP, HAC, and PNF is a reliable reconstruction technique that provides immediate and complete CSF leakage repair and mucosal grafting on the skull base without the need to harvest autologous tissue or perform postoperative CSF diversion. However, postoperative meningitis should be monitored carefully.