Background: The retinoblastoma (RB) protein which is encoded by RB gene selectively provides a cell type-specific function in malignancies. In colorectal carcinoma, RB has been highly expressed and related cyclin/cyclin-dependent kinase 4/6 inhibitors have shown improved therapeutic effects in some patients. However, little is known about RB in small intestinal adenocarcinoma (SIAC). Methods: Here, we conducted a multi-institutional study of RB expression in 229 surgically resected SIACs to explore the clinicopathologic and prognostic implications and the relationship with microsatellite instability (MSI) status and KRAS mutations. Results: High RB expression (RBHigh ) was more commonly observed in SIACs (76/229, 33%) than in normal small intestinal mucosa (27/188, 14%; P < 0.001). RBHigh was associated with nodular growth patterns (P = 0.028), the absence of lymphovascular (P = 0.001) and perineural invasion (P = 0.048), and a lower T category (P = 0.042) and indicated better overall survival (P = 0.003). In multivariate analysis, RBHigh (P = 0.049) was an independent prognostic predictor of better prognosis, along with younger patient age (P = 0.049), the absence of retroperitoneal seeding (P = 0.004), lower tumor stage (P < 0.001), and MSI (P = 0.005). The prognostic impact of RB expression was consistently observed regardless of MSI status and specifically persistent in SIACs with lower stages (stages I and II). Conclusion RBHigh was related to favorable clinicopathologic SIAC characteristics and indicated better patient prognosis. The prognostic predictability of RB was found in SIACs with lower stages, independent of MSI status. RB expression is a reliable and potent prognostic indicator for SIAC and may aid in selecting chemotherapy for patients.

Background: The retinoblastoma (RB) protein which is encoded by RB gene selectively provides a cell type-specific function in malignancies. In colorectal carcinoma, RB has been highly expressed and related cyclin/cyclin-dependent kinase 4/6 inhibitors have shown improved therapeutic effects in some patients. However, little is known about RB in small intestinal adenocarcinoma (SIAC). Methods: Here, we conducted a multi-institutional study of RB expression in 229 surgically resected SIACs to explore the clinicopathologic and prognostic implications and the relationship with microsatellite instability (MSI) status and KRAS mutations. Results: High RB expression (RBHigh ) was more commonly observed in SIACs (76/229, 33%) than in normal small intestinal mucosa (27/188, 14%; P < 0.001). RBHigh was associated with nodular growth patterns (P = 0.028), the absence of lymphovascular (P = 0.001) and perineural invasion (P = 0.048), and a lower T category (P = 0.042) and indicated better overall survival (P = 0.003). In multivariate analysis, RBHigh (P = 0.049) was an independent prognostic predictor of better prognosis, along with younger patient age (P = 0.049), the absence of retroperitoneal seeding (P = 0.004), lower tumor stage (P < 0.001), and MSI (P = 0.005). The prognostic impact of RB expression was consistently observed regardless of MSI status and specifically persistent in SIACs with lower stages (stages I and II). Conclusion RBHigh was related to favorable clinicopathologic SIAC characteristics and indicated better patient prognosis. The prognostic predictability of RB was found in SIACs with lower stages, independent of MSI status. RB expression is a reliable and potent prognostic indicator for SIAC and may aid in selecting chemotherapy for patients.

Background: The retinoblastoma (RB) protein which is encoded by RB gene selectively provides a cell type-specific function in malignancies. In colorectal carcinoma, RB has been highly expressed and related cyclin/cyclin-dependent kinase 4/6 inhibitors have shown improved therapeutic effects in some patients. However, little is known about RB in small intestinal adenocarcinoma (SIAC). Methods: Here, we conducted a multi-institutional study of RB expression in 229 surgically resected SIACs to explore the clinicopathologic and prognostic implications and the relationship with microsatellite instability (MSI) status and KRAS mutations. Results: High RB expression (RBHigh ) was more commonly observed in SIACs (76/229, 33%) than in normal small intestinal mucosa (27/188, 14%; P < 0.001). RBHigh was associated with nodular growth patterns (P = 0.028), the absence of lymphovascular (P = 0.001) and perineural invasion (P = 0.048), and a lower T category (P = 0.042) and indicated better overall survival (P = 0.003). In multivariate analysis, RBHigh (P = 0.049) was an independent prognostic predictor of better prognosis, along with younger patient age (P = 0.049), the absence of retroperitoneal seeding (P = 0.004), lower tumor stage (P < 0.001), and MSI (P = 0.005). The prognostic impact of RB expression was consistently observed regardless of MSI status and specifically persistent in SIACs with lower stages (stages I and II). Conclusion RBHigh was related to favorable clinicopathologic SIAC characteristics and indicated better patient prognosis. The prognostic predictability of RB was found in SIACs with lower stages, independent of MSI status. RB expression is a reliable and potent prognostic indicator for SIAC and may aid in selecting chemotherapy for patients.

Background: The retinoblastoma (RB) protein which is encoded by RB gene selectively provides a cell type-specific function in malignancies. In colorectal carcinoma, RB has been highly expressed and related cyclin/cyclin-dependent kinase 4/6 inhibitors have shown improved therapeutic effects in some patients. However, little is known about RB in small intestinal adenocarcinoma (SIAC). Methods: Here, we conducted a multi-institutional study of RB expression in 229 surgically resected SIACs to explore the clinicopathologic and prognostic implications and the relationship with microsatellite instability (MSI) status and KRAS mutations. Results: High RB expression (RBHigh ) was more commonly observed in SIACs (76/229, 33%) than in normal small intestinal mucosa (27/188, 14%; P < 0.001). RBHigh was associated with nodular growth patterns (P = 0.028), the absence of lymphovascular (P = 0.001) and perineural invasion (P = 0.048), and a lower T category (P = 0.042) and indicated better overall survival (P = 0.003). In multivariate analysis, RBHigh (P = 0.049) was an independent prognostic predictor of better prognosis, along with younger patient age (P = 0.049), the absence of retroperitoneal seeding (P = 0.004), lower tumor stage (P < 0.001), and MSI (P = 0.005). The prognostic impact of RB expression was consistently observed regardless of MSI status and specifically persistent in SIACs with lower stages (stages I and II). Conclusion RBHigh was related to favorable clinicopathologic SIAC characteristics and indicated better patient prognosis. The prognostic predictability of RB was found in SIACs with lower stages, independent of MSI status. RB expression is a reliable and potent prognostic indicator for SIAC and may aid in selecting chemotherapy for patients.

Background: s/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Background: Although many studies have been conducted on the association between the intercondylar notch size and the risk of anterior cruciate ligament (ACL) injury, few studies have examined its relationship with the condition after surgical treatment.Therefore, this study aimed to investigate the surgical outcomes of anatomical single-bundle ACL reconstruction according to intercondylar notch volumes. Methods: Medical records of patients who underwent anatomical single-bundle ACL reconstruction using a tibialis anterior allograft between 2015 and 2019 were retrospectively reviewed. For each sex, eligible patients were classified into two groups based on their percentile of intercondylar notch volumes, which were measured using postoperative three-dimensional computed tomography images (group S, ≤ 50th percentile of included patients; group L, > 50th percentile of included patients). Additional grouping was performed based on the group’s percentiles of normalized values of intercondylar notch volumes to body heights.Between-group comparative analyses were performed on the perioperative data and surgical outcomes in both objective and subjective aspects. Results: One hundred patients were included in the study. For male patients, there were no differences in the overall surgical outcomes between groups, whereas group L showed a significantly greater knee anteroposterior (AP) laxity than group S at the final follow-up (p = 0.042 for the side-to-side differences [SSD] at the maximum manual force). Similarly, there were no differences in the female patients in the overall surgical results between the groups, whereas group L showed a significantly greater knee AP laxity at the final follow-up (p = 0.020 for the SSD at 134 N; p = 0.011 for the SSD at the maximum manual force). Additional analyses based on the normalized values of the intercondylar notch volume showed consistent results for male patients, and additional grouping for female patients was identical to the existing grouping. Conclusions The surgical outcomes of anatomical single-bundle ACL reconstruction in patients with relatively small intercondylar notch volumes were comparable to those with large notch volumes, but rather showed favorable outcomes in postoperative knee AP laxity.

Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019.In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×105 plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×102 PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×102 PFU-virusinfected lungs from 2 dpi, but not in 1×105 PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×105PFU; however, 1×102 PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

Objective: : Collateral circulation is associated with the differential treatment effect of endovascular thrombectomy (EVT) in acute ischemic stroke. We aimed to verify the ability of the collateral map to predict futile EVT in patients with acute anterior circulation ischemic stroke. Methods: : This secondary analysis of a prospective observational study included data from participants underwent EVT for acute ischemic stroke due to occlusion of the internal carotid artery and/or the middle cerebral artery within 8 hours of symptom onset. Multiple logistic regression analyses were conducted to identify independent predictors of futile recanalization (modified Rankin scale score at 90 days of 4–6 despite of successful reperfusion). Results: : In a total of 214 participants, older age (odds ratio [OR], 2.40; 95% confidence interval [CI], 1.56 to 3.67; p<0.001), higher baseline National Institutes of Health Stroke Scale (NIHSS) scores (OR, 1.12; 95% CI, 1.04 to 1.21; p=0.004), very poor collateral perfusion grade (OR, 35.09; 95% CI, 3.50 to 351.33; p=0.002), longer door-to-puncture time (OR, 1.08; 95% CI, 1.02 to 1.14; p=0.009), and failed reperfusion (OR, 3.73; 95% CI, 1.30 to 10.76; p=0.015) were associated with unfavorable functional outcomes. In 184 participants who achieved successful reperfusion, older age (OR, 2.30; 95% CI, 1.44 to 3.67; p<0.001), higher baseline NIHSS scores (OR, 1.12; 95% CI, 1.03 to 1.22; p=0.006), very poor collateral perfusion grade (OR, 4.96; 95% CI, 1.42 to 17.37; p=0.012), and longer door-to-reperfusion time (OR, 1.09; 95% CI, 1.03 to 1.15; p=0.003) were associated with unfavorable functional outcomes. Conclusion : The assessment of collateral perfusion status using the collateral map can predict futile EVT, which may help select ineligible patients for EVT, thereby potentially reducing the rate of futile EVT.

Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Background: The risk of device thrombosis and device-oriented clinical outcomes with bioresorbable vascular scaffold (BVS) was reported to be significantly higher than with contemporary drug-eluting stents (DESs). However, optimal device implantation may improve clinical outcomes in patients receiving BVS. The current study evaluated mid-term safety and efficacy of Absorb BVS with meticulous device optimization under intravascular imaging guidance. Methods: The SMART-REWARD and PERSPECTIVE-PCI registries in Korea prospectively enrolled 390 patients with BVS and 675 patients with DES, respectively. The primary endpoint was target vessel failure (TVF) at 2 years and the secondary major endpoint was patientoriented composite outcome (POCO) at 2 years. Results: Patient-level pooled analysis evaluated 1,003 patients (377 patients with BVS and 626 patients with DES). Mean scaffold diameter per lesion was 3.24 ± 0.30 mm in BVS group.Most BVSs were implanted with pre-dilatation (90.9%), intravascular imaging guidance (74.9%), and post-dilatation (73.1%) at proximal to mid segment (81.9%) in target vessel.Patients treated with BVS showed comparable risks of 2-year TVF (2.9% vs. 3.7%, adjusted hazard ratio [HR], 1.283, 95% confidence interval [CI], 0.487–3.378, P = 0.615) and 2-year POCO (4.5% vs. 5.9%, adjusted HR, 1.413, 95% CI, 0.663–3.012,P = 0.370) than those with DES. The rate of 2-year definite or probable device thrombosis (0.3% vs. 0.5%, P = 0.424) was also similar. The sensitivity analyses consistently showed comparable risk of TVF and POCO between the 2 groups. Conclusion With meticulous device optimization under imaging guidance and avoidance of implantation in small vessels, BVS showed comparable risks of 2-year TVF and device thrombosis with DES.