Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant (B.1.1.529) is dominating coronavirus disease 2019 (COVID-19) worldwide. The waning protective effect of available vaccines against the Omicron variant is a critical public health issue. This study aimed to assess the impact of the third COVID-19 vaccination on immunity against the SARS-CoV-2 Omicron BA.1 strain in older individuals. Materials and Methods: Adults aged ≥60 years who had completed two doses of the homologous COVID-19 vaccine with either BNT162b2 (Pfizer/BioNTech, New York, NY, USA, BNT) or ChAdOx1 nCoV (SK bioscience, Andong-si, Gyeongsangbuk-do, Korea, ChAd) were registered to receive the third vaccination. Participants chose either BNT or mRNA-1273 (Moderna, Norwood, MA, USA, m1273) mRNA vaccine for the third dose and were categorized into four groups: ChAd/ChAd/BNT, ChAd/ChAd/m1273, BNT/BNT/BNT, and BNT/BNT/m1273. Four serum specimens were obtained from each participant at 0, 4, 12, and 24 weeks after the third dose (V1, V2, V3, and V4, respectively).Serum-neutralizing antibody (NAb) activity against BetaCoV/Korea/KCDC03/2020 (NCCP43326, ancestral strain) and B.1.1.529 (NCCP43411, Omicron BA.1 variant) was measured using plaque reduction neutralization tests. A 50% neutralizing dilution (ND 50 ) >10 was considered indicative of protective NAb titers. Results: In total, 186 participants were enrolled between November 24, 2021, and June 30, 2022. The respective groups received the third dose at a median (interquartile range [IQR]) of 132 (125 - 191), 123 (122 - 126), 186 (166 -193), and 182 (175 - 198) days after the second dose. Overall, ND 50 was lower at V1 against Omicron BA.1 than against the ancestral strain. NAb titers against the ancestral strain and Omicron BA.1 variant at V2 were increased at least 30-fold (median [IQR], 1235.35 [1021.45 - 2374.65)] and 129.8 [65.3 - 250.7], respectively). ND 50 titers against the ancestral strain and Omicron variant did not differ significantly among the four groups (P= 0.57). NAb titers were significantly lower against the Omicron variant than against the ancestral strain at V3 (median [IQR], 36.4 (17.55 - 75.09) vs. 325.9 [276.07 - 686.97]; P = 0.012). NAb titers against Omicron at V4 were 16 times lower than that at V3. Most sera exhibited a protective level (ND 50 >10) at V4 (75.0% [24/32], 73.0% [27/37], 73.3% [22/30], and 70.6% [12/17] in the ChAd/ChAd/BNT, ChAd/ChAd/m1273, BNT/BNT/BNT, and BNT/BNT/m1273 groups, respectively), with no significant differences among groups (P = 0.99). Conclusion A third COVID-19 mRNA vaccine dose restored waning NAb titers against Omicron BA.1. Our findings support a third-dose vaccination program to prevent the waning of humoral immunity to SARS-CoV-2.

Background: We aimed to analyze the impact of concomitant Maze procedure on the clinical and rhythm outcomes, and echocardiographic parameters in tricuspid repair for patients with severe tricuspid regurgitation (TR) and persistent atrial fibrillation (AF). Methods: Patients who had severe TR and persistent AF and underwent tricuspid valve (TV) repair were included in the study. Both primary TR and secondary TR were included in the current study. The study population was stratified according to Maze procedure. The primary outcome was major adverse cardiovascular and cerebrovascular event (MACCE) at 15 years postsurgery. Propensity-score matching analyses was performed to adjust baseline differences. Results: Three hundred seventy-one patients who underwent tricuspid repair for severe TR and persistent AF from 1994 to 2021 were included, and 198 patients (53.4%) underwent concomitant Maze procedure. The maze group showed 10-year sinus rhythm (SR) restoration rate of 55%. In the matched cohort, the maze group showed a lower cumulative incidence of cardiac death (4.6% vs. 14.4%, P = 0.131), readmission for heart failure (8.1% vs. 22.2%, P = 0.073), and MACCE (21.1% vs. 42.1%, P = 0.029) at 15 years compared to the non-maze group. Left atrial (LA) diameter significantly decreased in the maze group at 5 years (53.3 vs. 59.6 mm, P < 0.001) after surgery compared to preoperative level, and there was a significant difference in the change of LA diameter over time between the two groups (P = 0.013). Conclusion The Maze procedure during TV repair in patients with severe TR and persistent AF showed acceptable SR rates and lower MACCE rates compared to those without the procedure, while also promoting LA reverse remodeling.

Purpose: In this study, subjects with femoral anterior glide type were examined to investigate the effects of femoral head anterior glide fixation during active straight leg raise on the strength of the hip flexor in a supine position. Methods: Fifteen subjects participated in this study. All subjects were classified through an evaluation form for femoral anterior glide type (FAGT). The strength of the hip flexor was measured during active straight leg raise test (ASLR test), and compared with and without femoral anterior glide fixation in a supine position. The fixation of the femoral head was achieved as per the therapist’s manual guidelines. Paired t-test was applied to compare changes in the strength of the hip flexor according to fixation conditions. The level of statistical significance was set at α= 0.05. Results: The strength of the hip flexor was lesser during the ASLR test with fixation compared to without fixation (p= 0.007). Conclusion The strength of the hip flexor decreases with fixation. Results of this study revealed a difference between hip flexor strength, with and without femoral anterior glide fixation during ASLR, in subjects with femoral anterior glide type.

Background: Gaucher disease (GD) is an autosomal recessive disorder characterized by excessive accumulation of glucosylceramide in multiple organs. This study was performed to determine the detection rate of GD in a selected patient population with unexplained splenomegaly in Korea. Methods: This was a multicenter, observational study conducted at 18 sites in Korea between December 2016 and February 2020. Adult patients with unexplained splenomegaly were enrolled and tested for β-glucosidase enzyme activity on dried blood spots (DBS) and in peripheral blood leukocytes. Mutation analysis was performed if the test was positive or indeterminate for the enzyme assay. The primary endpoint was the percentage of patients with GD in patients with unexplained splenomegaly. Results: A total of 352 patients were enrolled in this study (male patients, 199; mean age, 48.42 yr). Amongst them, 14.77% of patients had concomitant hepatomegaly. The most common sign related to GD was splenomegaly (100%), followed by thrombocytopenia (44.32%) and, anemia (40.91%). The β-glucosidase activity assay on DBS and peripheral leukocytes showed abnormal results in sixteen and six patients, respectively. Eight patients were tested for the mutation, seven of whom were negative and one patient showed a positive mutation analysis result. One female patient who presented with splenomegaly and thrombocytopenia was diagnosed with type 1 GD. The detection rate of GD was 0.2841% (exact 95% CI, 0.0072‒). Conclusion The detection rate of GD in probable high-risk patients in Korea was lower than expected.However, the role of hemato-oncologists is still important in the diagnosis of GD.

Purpose: Pegfilgrastim is widely used to prevent chemotherapy-induced neutropenia (CIN) and febrile neutropenia (FN) in patients with diffuse large B-cell lymphoma (DLBCL). We investigated the predictive factors affecting CIN and FN incidence in patients with DLBCL receiving rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy with pegfilgrastim and conducted experiments to find reason for the occurrence of CIN even when pegfilgrastim was used. Materials and Methods: We reviewed the CIN and FN events of 200 patients with DLBCL. Based on these data, we investigate the association with predictive factor and the levels of granulocyte-colony stimulating factor (G-CSF) receptor signaling pathway markers (pSTAT3, pAKT, pERK1/2, pBAD, and CXCR4) in bone marrow (BM) samples isolated from patients with DLBCL. Results: FN was significantly associated with stage III/IV (hazard ratio [HR], 12.74) and low serum albumin levels (HR, 3.87). Additionally, patients with FN had lower progression-free survival (PFS; 2-year PFS, 51.1 % vs. 74.0%) and overall survival (OS; 2-year OS, 58.2% vs. 85.0%) compared to those without FN. The occurrence of CIN was associated with overexpression of G-CSF receptor signaling pathway markers, and expression levels of these markers were upregulated in BM cells co-cultured with DLBCL cells. The rate of neutrophil apoptosis was also higher in neutrophils co-cultured with DLBCL cells and was further promoted by treatment with doxorubicin. Conclusion Our findings suggest that high DLBCL burden may alter the BM environment and G-CSF receptor signaling pathway, even in chemotherapy-naïve state, which may increase CIN frequency during R-CHOP chemotherapy.

Background: To estimate real-world outcomes in East Asian populations, we conducted a nationwide retrospective analysis of the efficacy and safety of lenalidomide for del(5q) myelodysplastic syndrome (MDS) patients with transfusion-dependent anemia in Korea. Methods: Patients aged ≥19 years who had received lenalidomide for the treatment of lower-risk, red blood cell (RBC) transfusion-dependent del(5q) MDS were selected. A filled case report form (CRF) with information from electronic medical records was requested from members of the acute myeloid leukemia (AML)/MDS Working Party of the Korean Society of Hematology. All the CRFs were gathered and analyzed. Results: A total of 31 patients were included in this study. Of 28 evaluable patients, 19 (67.9%) achieved RBC transfusion independence (RBC-TI). Female sex and the development of thrombocytopenia during treatment were associated with achieving RBC-TI. The most common non-hematologic toxicities were pruritus, fatigue, and rashes. All non-hematologic toxicities of grades ≥3 were limited to rash (12.9%) and pruritus (6.5%). Dose reduction was required in 15 of the 19 responders (78.9%). The most common final stable dosing schedule for the responders was 5 mg once every other day (31.6%). Conclusion Lenalidomide efficacy and tolerability were similar in the Asian del(5q) MDS patients and western patients. Dose reduction during treatment was common, but it was not associated with inferior outcomes.

Background/Aims: The utility of endoscopic ultrasonography (EUS) for differentiating gastrointestinal stromal tumors (GISTs) and leiomyomas of the stomach is not well known. We aimed to evaluate the ability of EUS for differentiating gastric GISTs and leiomyomas. Methods: We retrospectively reviewed the medical records of patients with histopathologically proven GISTs (n=274) and leiomyomas (n=87). In two consensus meetings, the inter-observer variability in the EUS image analysis was reduced. Using logistic regression analyses, we selected predictive factors and constructed a predictive model and nomogram for differentiating GISTs from leiomyomas. A receiver operating characteristic (ROC) curve analysis was performed to measure the discrimination performance in the development and internal validation sets. Results: Multivariate analysis identified heterogeneity (odds ratio [OR], 9.48), non-cardia (OR, 19.11), and older age (OR, 1.06) as independent predictors of GISTs. The areas under the ROC curve of the predictive model using age, sex, and four EUS factors (homogeneity, location, anechoic spaces, and dimpling or ulcer) were 0.916 (sensitivity, 0.908; specificity, 0.793) and 0.904 (sensitivity, 0.908; specificity, 0.782) in the development and internal validation sets, respectively. Conclusions The predictive model and nomogram using age, sex and homogeneity, tumor location, presence of anechoic spaces, and presence of dimpling or ulcer on EUS may facilitate differentiation between GISTs and leiomyomas.

Background/Aims: To date, no reports have compared the diagnostic efficacy of narrow-band imaging (NBI) and i-scan for the histologic prediction of intermediate-to-large colorectal polyps. We aimed to compare the diagnostic accuracy of NBI and i-scan in predicting histology, and their inter-/intra-observer agreement. Methods: We performed a prospective, randomized study that included 66 patients (NBI, n=33 vs. i-scan, n=33) with colorectal polyps (size >10 mm but <50 mm) who underwent colonoscopic resection. During the procedure, three endoscopists documented their prediction using the Japan NBI Expert Team (JNET) classification. Two months after study completion, the endoscopists reviewed still images and video clips for analysis. Results: The overall diagnostic accuracies in the NBI and i-scan groups were 73.7% (73/99) and 75.8% (75/99), respectively, and there was no statistical significance between the two groups (p=0.744). The JNET classification as applied to NBI and i-scan showed substantial inter-observer agreement (NBI κ-value 0.612, p=0.001 vs. i-scan κ-value 0.662, p=0.002). Additionally, the κ-values of intra-observer agreement were in the range of 0.385–0.660 with NBI and 0.364–0.741 with i-scan. Conclusions NBI and i-scan have similar diagnostic accuracies for the histologic prediction of intermediate-to-large colorectal polyps. Furthermore, the inter-/intra-observer agreement was acceptable for both modalities when the JNET classification was applied.

Background: To estimate real-world outcomes in East Asian populations, we conducted a nationwide retrospective analysis of the efficacy and safety of lenalidomide for del(5q) myelodysplastic syndrome (MDS) patients with transfusion-dependent anemia in Korea. Methods: Patients aged ≥19 years who had received lenalidomide for the treatment of lower-risk, red blood cell (RBC) transfusion-dependent del(5q) MDS were selected. A filled case report form (CRF) with information from electronic medical records was requested from members of the acute myeloid leukemia (AML)/MDS Working Party of the Korean Society of Hematology. All the CRFs were gathered and analyzed. Results: A total of 31 patients were included in this study. Of 28 evaluable patients, 19 (67.9%) achieved RBC transfusion independence (RBC-TI). Female sex and the development of thrombocytopenia during treatment were associated with achieving RBC-TI. The most common non-hematologic toxicities were pruritus, fatigue, and rashes. All non-hematologic toxicities of grades ≥3 were limited to rash (12.9%) and pruritus (6.5%). Dose reduction was required in 15 of the 19 responders (78.9%). The most common final stable dosing schedule for the responders was 5 mg once every other day (31.6%). Conclusion Lenalidomide efficacy and tolerability were similar in the Asian del(5q) MDS patients and western patients. Dose reduction during treatment was common, but it was not associated with inferior outcomes.

Objective: The size and location of ureter stones are important factors in their spontaneous passage. We compared the clinical characteristics and neutrophil-lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), and C-reactive protein (CRP) of patients who visited the emergency department with ureter stones of ≥5 mm and <5 mm in size. Methods: We retrospectively reviewed 699 patients who visited the emergency department of two medical centers from January 2017 to December 2019. We compared microscopic hematuria, pyuria, NLR, PLR, CRP, the grade of hydronephrosis, and the location of ureteral calculi between the two groups. Results: There were 419 patients with ureter stones less than 5 mm and 280 patients with stones more than 5 mm in size. NLR was 2.82 (1.44-4.73) and 3.12 (1.94-5.75) in patients with stones <5 mm and ≥5 mm, respectively (P=0.001). PLR was 117.2 (88.2-164.9) and 136.0 (98.9-199.7) in patients with stones <5 mm and ≥5 mm, respectively (P=0.001). CRP was 0.29 (0.29-0.29) and 0.29 (0.29-1.04) in patients with stones <5 mm and ≥5 mm, respectively (P<0.001). The proportion of microscopic hematuria was 84.7% and 76.4% in patients with stones <5 mm and ≥5 mm, respectively (P=0.006). The proportion of pyuria was 20.5% and 41.8% in patients with stones <5 mm and ≥5 mm, respectively (P=0.01). Conclusion In patients with ureter stones ≥5 mm, CRP, NLR, and PLR were significantly higher than patients with ureter stones <5 mm. However, further studies are needed before using these indicators to make clinical decisions regarding ureteral stone management.