Purpose: This study evaluates the Korean Cancer Study Group Geriatric Score-7 (KG-7) frailty screening tool’s effectiveness in elderly multiple myeloma (MM) patients to prevent under and overtreatment. Materials and Methods: This prospective pilot cohort study included 100 elderly patients aged 70 and older with newly diagnosed MM who had not undergone transplantation from August 2020 to January 2022. Results: The median age was 77 years, and 73.0% of patients were classified at International Staging System stages 2 or 3. Using a 5-point cutoff on the KG-7 index (non-frail, score ≥ 5; frail, score < 5), 31% were categorized as frail. After a median follow-up of 26.8 months, the 3-year overall survival rate was 73.0%. There was no statistically significant association between any frailty index and the risk of death. However, frail patients defined by the simplified frailty index (hazard ratio [HR], 2.49; 95% confidence interval [CI], 1.09 to 5.95; p=0.030) and by KG-7 (HR, 2.43; 95% CI, 1.03 to 5.86; p=0.043) had a significantly higher risk of grade 3-4 non-hematologic toxicity, whereas the International Myeloma Working Group definition did not. Over a 24-month tracking period, vulnerability as measured by KG-7 either improved or deteriorated. Conclusion The pilot study, which had a limited number of participants, did not demonstrate KG-7’s effectiveness in predicting survival; however, it successfully predicted severe non-hematologic toxicities. We plan to conduct larger studies in elderly MM patients to determine whether KG-7 can help tailor their treatment regimens.

Background: Our study aimed to evaluate the clinical and radiologic results of all-arthroscopic treatment of terrible triad injuries followed-up for a minimum of 5 years and investigate how arthroscopic partial excision for radial head fractures affects the results at the final follow-up. Methods: We retrospectively reviewed consecutive patients with terrible triad injuries who underwent all-arthroscopic treatment between January 2011 and June 2018. In group I, we performed conservative or arthroscopic fixation of stable radial head fractures, while in group II, arthroscopic partial excision of unstable radial head fractures involving <30%–50% of the articular surface area was performed. Clinical outcomes were measured by visual analog scale score and assessment of instability, range of motion (ROM), and Mayo Elbow Performance Score. Radiological outcomes were evaluated using x-rays, and the integrity of the repaired lateral collateral ligament complex was confirmed through magnetic resonance imaging. Results: Thirty-two patients with an average age of 49.5±16.2 years met the inclusion criteria and were followed-up for a mean of 82.7±22.2 months. Twenty patients were assigned to group I and 12 patients to group II. Clinical outcomes showed no significant differences between the two groups at the final follow-up (P>0.05). On radiological evaluation, more heterotopic ossifications were found in the radial head excision group (group II, 66.7% vs. group I, 35%; P=0.02); however, there was no significant difference in ROM between the two groups (P>0.05). Conclusions In all-arthroscopic treatment of terrible triad injuries, arthroscopic partial excision of the radial head did not seem to have a significant impact on elbow joint stability.Level of evidence: III.

Background: Our study aimed to evaluate the clinical and radiologic results of all-arthroscopic treatment of terrible triad injuries followed-up for a minimum of 5 years and investigate how arthroscopic partial excision for radial head fractures affects the results at the final follow-up. Methods: We retrospectively reviewed consecutive patients with terrible triad injuries who underwent all-arthroscopic treatment between January 2011 and June 2018. In group I, we performed conservative or arthroscopic fixation of stable radial head fractures, while in group II, arthroscopic partial excision of unstable radial head fractures involving <30%–50% of the articular surface area was performed. Clinical outcomes were measured by visual analog scale score and assessment of instability, range of motion (ROM), and Mayo Elbow Performance Score. Radiological outcomes were evaluated using x-rays, and the integrity of the repaired lateral collateral ligament complex was confirmed through magnetic resonance imaging. Results: Thirty-two patients with an average age of 49.5±16.2 years met the inclusion criteria and were followed-up for a mean of 82.7±22.2 months. Twenty patients were assigned to group I and 12 patients to group II. Clinical outcomes showed no significant differences between the two groups at the final follow-up (P>0.05). On radiological evaluation, more heterotopic ossifications were found in the radial head excision group (group II, 66.7% vs. group I, 35%; P=0.02); however, there was no significant difference in ROM between the two groups (P>0.05). Conclusions In all-arthroscopic treatment of terrible triad injuries, arthroscopic partial excision of the radial head did not seem to have a significant impact on elbow joint stability.Level of evidence: III.

In recent years, treatment using implants has become common. Since 2016, dental implants have been insured as part of strengthening health insurance coverage. Consequently, the demand for implants is increasing. Accordingly, the importance of implant maintenance has been emphasized. Of which, implant retrievability is an important factor in implant success. Although the screw-retained type is an advantageous easy-to-retrieve prosthesis, an occlusal point cannot make it to the central axis of the implant. Thus, we aimed to introduce an implant setting method (screw hole indexing) that enables the maintenance of the proper occlusal point and enables retrievability by marking the screw holes of the implant.

Background: Our study aimed to evaluate the clinical and radiologic results of all-arthroscopic treatment of terrible triad injuries followed-up for a minimum of 5 years and investigate how arthroscopic partial excision for radial head fractures affects the results at the final follow-up. Methods: We retrospectively reviewed consecutive patients with terrible triad injuries who underwent all-arthroscopic treatment between January 2011 and June 2018. In group I, we performed conservative or arthroscopic fixation of stable radial head fractures, while in group II, arthroscopic partial excision of unstable radial head fractures involving <30%–50% of the articular surface area was performed. Clinical outcomes were measured by visual analog scale score and assessment of instability, range of motion (ROM), and Mayo Elbow Performance Score. Radiological outcomes were evaluated using x-rays, and the integrity of the repaired lateral collateral ligament complex was confirmed through magnetic resonance imaging. Results: Thirty-two patients with an average age of 49.5±16.2 years met the inclusion criteria and were followed-up for a mean of 82.7±22.2 months. Twenty patients were assigned to group I and 12 patients to group II. Clinical outcomes showed no significant differences between the two groups at the final follow-up (P>0.05). On radiological evaluation, more heterotopic ossifications were found in the radial head excision group (group II, 66.7% vs. group I, 35%; P=0.02); however, there was no significant difference in ROM between the two groups (P>0.05). Conclusions In all-arthroscopic treatment of terrible triad injuries, arthroscopic partial excision of the radial head did not seem to have a significant impact on elbow joint stability.Level of evidence: III.

Background: Our study aimed to evaluate the clinical and radiologic results of all-arthroscopic treatment of terrible triad injuries followed-up for a minimum of 5 years and investigate how arthroscopic partial excision for radial head fractures affects the results at the final follow-up. Methods: We retrospectively reviewed consecutive patients with terrible triad injuries who underwent all-arthroscopic treatment between January 2011 and June 2018. In group I, we performed conservative or arthroscopic fixation of stable radial head fractures, while in group II, arthroscopic partial excision of unstable radial head fractures involving <30%–50% of the articular surface area was performed. Clinical outcomes were measured by visual analog scale score and assessment of instability, range of motion (ROM), and Mayo Elbow Performance Score. Radiological outcomes were evaluated using x-rays, and the integrity of the repaired lateral collateral ligament complex was confirmed through magnetic resonance imaging. Results: Thirty-two patients with an average age of 49.5±16.2 years met the inclusion criteria and were followed-up for a mean of 82.7±22.2 months. Twenty patients were assigned to group I and 12 patients to group II. Clinical outcomes showed no significant differences between the two groups at the final follow-up (P>0.05). On radiological evaluation, more heterotopic ossifications were found in the radial head excision group (group II, 66.7% vs. group I, 35%; P=0.02); however, there was no significant difference in ROM between the two groups (P>0.05). Conclusions In all-arthroscopic treatment of terrible triad injuries, arthroscopic partial excision of the radial head did not seem to have a significant impact on elbow joint stability.Level of evidence: III.

Purpose: This subgroup analysis of the Korean subset of patients in the phase 3 LASER301 trial evaluated the efficacy and safety of lazertinib versus gefitinib as first-line therapy for epidermal growth factor receptor mutated (EGFRm) non–small cell lung cancer (NSCLC). Materials and Methods: Patients with locally advanced or metastatic EGFRm NSCLC were randomized 1:1 to lazertinib (240 mg/day) or gefitinib (250 mg/day). The primary endpoint was investigator-assessed progression-free survival (PFS). Results: In total, 172 Korean patients were enrolled (lazertinib, n=87; gefitinib, n=85). Baseline characteristics were balanced between the treatment groups. One-third of patients had brain metastases (BM) at baseline. Median PFS was 20.8 months (95% confidence interval [CI], 16.7 to 26.1) for lazertinib and 9.6 months (95% CI, 8.2 to 12.3) for gefitinib (hazard ratio [HR], 0.41; 95% CI, 0.28 to 0.60). This was supported by PFS analysis based on blinded independent central review. Significant PFS benefit with lazertinib was consistently observed across predefined subgroups, including patients with BM (HR, 0.28; 95% CI, 0.15 to 0.53) and those with L858R mutations (HR, 0.36; 95% CI, 0.20 to 0.63). Lazertinib safety data were consistent with its previously reported safety profile. Common adverse events (AEs) in both groups included rash, pruritus, and diarrhoea. Numerically fewer severe AEs and severe treatment–related AEs occurred with lazertinib than gefitinib. Conclusion Consistent with results for the overall LASER301 population, this analysis showed significant PFS benefit with lazertinib versus gefitinib with comparable safety in Korean patients with untreated EGFRm NSCLC, supporting lazertinib as a new potential treatment option for this patient population.

Background: The Omicron variant has become the most prevalent SARS-CoV-2 variant. Omicron is known to induce milder lesions compared to the original Wuhan strain. Fatal infection of the Wuhan strain into the brain has been well documented in COVID-19 mouse models and human COVID-19 cases, but apparent infections into the brain by Omicron have not been reported in human adult cases or animal models. In this study, we investigated whether Omicron could spread to the brain using K18-hACE2 mice susceptible to SARS-CoV-2 infection. Results: K18-hACE2 mice were intranasally infected with 1 × 105 PFU of the original Wuhan strain and the Omicron variant of SARS-CoV-2. A follow-up was conducted 7 days post infection. All Wuhan-infected mice showed > 20% body weight loss, defined as the lethal condition, whereas two out of five Omicron-infected mice (40%) lost > 20% body weight. Histopathological analysis based on H&E staining revealed inflammatory responses in the brains of these two Omicron-infected mice. Immunostaining analysis of viral nucleocapsid protein revealed severe infection of neuron cells in the brains of these two Omicron-infected mice. Lymphoid depletion and apoptosis were observed in the spleen of Omicron-infected mice with brain infection. Conclusion Lethal conditions, such as severe body weight loss and encephalopathy, can occur in Omicron-infected K18-hACE2 mice. Our study reports, for the first time, that Omicron can induce brain infection with lymphoid depletion in the mouse COVID-19 model.

Background/Aims: Little attention is paid to chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) in Korea due to the rarity of the disease. With its rising incidence, we aimed to evaluate recent changes in treatment patterns and survival outcomes of patients with CLL/SLL. Methods: A total of 141 patients diagnosed with CLL/SLL between January 2010 and March 2020 who received systemic therapy were analyzed in this multicenter retrospective study. Results: The median patient age was 66 years at diagnosis, and 68.1% were male. The median interval from diagnosis to initial treatment was 0.9 months (range: 0–77.6 months), and the most common treatment indication was progressive marrow failure (50.4%). Regarding first-line therapy, 46.8% received fludarabine, cyclophosphamide, plus rituximab (FCR), followed by chlorambucil (19.9%), and obinutuzumab plus chlorambucil (GC) (12.1%). The median progression-free survival (PFS) was 49.3 months (95% confidence interval [CI], 32.7–61.4), and median overall survival was not reached (95% CI, 98.4 mo– not reached). Multivariable analysis revealed younger age (≤ 65 yr) (hazard ratio [HR], 0.46; p < 0.001) and first-line therapy with FCR (HR, 0.64; p = 0.019) were independently associated with improved PFS. TP53 aberrations were observed in 7.0% (4/57) of evaluable patients. Following reimbursement, GC became the most common therapy among patients over 65 years and second in the overall population after 2017. Conclusions Age and reimbursement mainly influenced treatment strategies. Greater effort to apply risk stratifications into practice and clinical trials for novel agents could help improve treatment outcomes in Korean patients.

Purpose: We conducted a nationwide, multicenter, prospective registry study for newly diagnosed patients with peripheral T-cell lymphoma (PTCL) to better define the clinical characteristics, treatment patterns, survival outcomes, and the role of upfront autologous stem cell transplantation (ASCT) in these patients. Materials and Methods: Patients with PTCL receiving chemotherapy with curative intent were registered and prospectively monitored. All patients were pathologically diagnosed with PTCL. Results: A total of 191 patients with PTCL were enrolled in this prospective registry study. PTCL, not otherwise specified (PTCL-NOS) was the most common pathologic subtype (n=80, 41.9%), followed by angioimmunoblastic T-cell lymphoma (AITL) (n=60, 31.4%). With a median follow-up duration of 3.9 years, the 3-year progression-free survival (PFS) and overall survival (OS) rates were 39.5% and 60.4%, respectively. The role of upfront ASCT was evaluated in patients who were considered transplant-eligible (n=59). ASCT was performed as an upfront consolidative treatment in 32 (54.2%) of these patients. There were no significant differences in PFS and OS between the ASCT and non-ASCT groups for all patients (n=59) and for patients with PTCL-NOS (n=26). However, in patients with AITL, the ASCT group was associated with significantly better PFS than the non-ASCT group, although there was no significant difference in OS. Conclusion The current study demonstrated that the survival outcomes with the current treatment options remain poor for patients with PTCL-NOS. Upfront ASCT may provide a survival benefit for patients with AITL, but not PTCL-NOS.