Purpose: Alzheimer’s disease (AD) dementia may not be a single disease entity. Early-onset AD (EOAD) and late-onset AD (LOAD) have been united under the same eponym of AD until now, but disentangling the heterogeneity according to the age of sonset has been a major tenet in the field of AD research. Materials and Methods: Ninety-nine patients with AD (EOAD, n=54; LOAD, n=45) and 66 cognitively normal controls completed both [18F]THK5351 and [18F]flutemetamol (FLUTE) positron emission tomography scans along with structural magnetic resonance imaging and detailed neuropsychological tests. Results: EOAD patients had higher THK retention in the precuneus, parietal, and frontal lobe, while LOAD patients had higher THK retention in the medial temporal lobe. Intravoxel correlation analyses revealed that EOAD presented narrower territory of local FLUTE-THK correlation, while LOAD presented broader territory of correlation extending to overall parieto-occipito-temporal regions. EOAD patients had broader brain areas which showed significant negative correlations between cortical thickness and THK retention, whereas in LOAD, only limited brain areas showed significant correlation with THK retention. In EOAD, most of the cognitive test results were correlated with THK retention. However, a few cognitive test results were correlated with THK retention in LOAD. Conclusion LOAD seemed to show gradual increase in tau and amyloid, and those two pathologies have association to each other. On the other hand, in EOAD, tau and amyloid may develop more abruptly and independently. These findings suggest LOAD and EOAD may have different courses of pathomechanism.

Background: The goal of induction therapy for multiple myeloma (MM) is to achieve adequate disease control. Current guidelines favor triplet (bortezomib-lenalidomide-dexamethasone;VRd) or quadruplet regimens (daratumumab, bortezomib-thalidomide-dexamethasone;D-VTd). In the absence of a direct comparison between two treatment regimens, we conducted this study to compare the outcomes and safety of VRd and D-VTd. Methods: Newly diagnosed MM patients aged ＞18 years who underwent induction therapy followed by autologous stem cell transplantation (ASCT) between November 2020 and December 2021 were identified. Finally, patients with VRd (N=37) and those with D-VTd (N=43) were enrolled. Results: After induction, 10.8% of the VRd group showed stringent complete remission (sCR), 21.6% showed complete response (CR), 35.1% showed very good partial response (VGPR), and 32.4% showed partial response (PR). Of the D-VTd group, 9.3% showed sCR, 34.9% CR, 48.8% VGPR, and 4.2% PR (VGPR or better: 67.6% in VRd vs. 93% in D-VTd, P =0.004). After ASCT, 68.6% of the VRd group showed CR or sCR, while 90.5% of the D-VTd group showed CR or sCR (P=0.016). VRd was associated with an increased incidence of skin rash (P=0.044). Other than rashes, there were no significant differences in terms of adverse events between the two groups. Conclusion Our study supports the use of a front-line quadruplet induction regimen containing a CD38 monoclonal antibody for transplant-eligible patients with newly diagnosed MM.

Purpose: The treatment of male breast cancer (MBC) has been extrapolated from female breast cancer (FBC) because of its rarity despite their different clinicopathologic characteristics. We aimed to investigate the distribution of intrinsic subtypes based on immunohistochemistry, their clinical impact, and treatment pattern in clinical practice through a multicenter study in Korea. Materials and Methods: We retrospectively analyzed clinical data of 248 MBC patients from 18 institutions across the country from January 1995 to July 2016. Results: The median age of MBC patients was 63 years (range, 25 to 102 years). Among 148 intrinsic subtype classified patients, 61 (41.2%), 44 (29.7%), 29 (19.5%), and 14 (9.5%) were luminal A, luminal B, human epidermal growth factor receptor 2, and triple-negative breast cancer, respectively. Luminal A subtype showed trends for superior survival compared to other subtypes. Most hormone receptor-positive patients (166 patients, 82.6%) received adjuvant endocrine treatment. Five-year completion of adjuvant endocrine treatment was associated with superior disease-free survival (DFS) in patients classified with an intrinsic subtype (hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.04 to 0.49; p=0.002) and in all patients (HR, 0.16; 95% CI, 0.05 to 0.54; p=0.003). Conclusion Distribution of subtypes of MBC was similar to FBC and luminal type A was most common. Overall survival tended to be improved for luminal A subtype, although there was no statistical significance. Completion of adjuvant endocrine treatment was associated with prolonged DFS in intrinsic subtype classified patients. MBC patients tended to receive less treatment. MBC patients should receive standard treatment according to guidelines as FBC patients.

Background: Although most studies focused on the alignment or union of the tibia in same-level distal third tibiofibular fractures, the outcome of a concomitant fibular fracture is generally regarded as being of secondary importance in the literature. This study aimed to assess the outcomes of fibular fractures in same-level distal third tibiofibular fractures. Methods: In this retrospective study, we enrolled 111 patients with same-level distal third tibiofibular fractures treated at our institute between January 2016 and August 2020. Tibial fractures were stabilized with intramedullary nailing, and the cases were divided into two groups based on whether they additionally underwent fibular fixation (group 1, 57 cases) or not (group 2, 54 cases). Clinical and radiographic outcomes were used for the evaluation of tibial and fibular alignments, union of the tibia and fibula, number of interlocking screws in the distal tibial fragment, range of motion of the ankle joint, and complications. Results: No statistically significant differences in the tibial union rate or mean tibial alignment were observed between the two groups on either the immediate postoperative or final radiographs. The fibular union rate in group 1 was significantly higher than that in group 2 (fibular nonunion, 0 vs. 15; p < 0.001). Statistically significant differences in fibular displacement were observed on immediate postoperative radiographs between patients with fibular union and those without it. At the final follow-up, the mean range of ankle motion and lower extremity functional scale scores did not differ between the two groups. Conclusions Regardless of whether fibular fixation was performed, the overall tibial alignment with intramedullary nailing was well restored and the union rate of the tibia was comparable in the two groups. Fibular nonunion is not uncommon in unfixed fibula fractures. Displacement of the fibula as seen on immediate postoperative radiographs was related to fibular nonunion.

Purpose: Oxaliplatin, a component of the capecitabine plus oxaliplatin (XELOX) regimen, has a more favorable toxicity profile than cisplatin in patients with advanced gastric cancer (GC). However, oxaliplatin can induce sensory neuropathy and cumulative, dose-related toxicities. Thus, the capecitabine maintenance regimen may achieve the maximum treatment effect while reducing the cumulative neurotoxicity of oxaliplatin. This study aimed to compare the survival of patients with advanced GC between capecitabine maintenance and observation after 1st line XELOX chemotherapy. Materials and Methods: Sixty-three patients treated with six cycles of XELOX for advanced GC in six hospitals of the Catholic University of Korea were randomized 1:1 to receive capecitabine maintenance or observation. The primary endpoint was progression-free survival (PFS), analyzed using a two-sided log-rank test stratified at a 5% significance level. Results: Between 2015 and 2020, 32 and 31 patients were randomized into the maintenance and observation groups, respectively. After randomization, the median number of capecitabine maintenance cycles was 6. The PFS was significantly higher in the maintenance group than the observation group (6.3 vs. 4.1 months, P=0.010). Overall survival was not significantly different between the 2 groups (18.2 vs. 16.5 months, P=0.624). Toxicities, such as hand-foot syndrome, were reported in some maintenance group patients. Maintenance treatment was a significant factor associated with PFS in multivariate analysis (hazard ratio, 0.472; 95% confidence interval, 0.250–0.890; P=0.020). Conclusions After 6 cycles of XELOX chemotherapy, capecitabine maintenance significantly prolonged PFS compared with observation, and toxicity was manageable. Maintenance treatment was a significant prognostic factor associated with PFS.

Background: Fractional flow reserve (FFR) based on computed tomography (CT) has been shown to better identify ischemia-causing coronary stenosis. However, this current technology requires high computational power, which inhibits its widespread implementation in clinical practice. This prospective, multicenter study aimed at validating the diagnostic performance of a novel simple CT based fractional flow reserve (CT-FFR) calculation method in patients with coronary artery disease. Methods: Patients who underwent coronary CT angiography (CCTA) within 90 days and invasive coronary angiography (ICA) were prospectively enrolled. A hemodynamically significant lesion was defined as an FFR ≤ 0.80, and the area under the receiver operating characteristic curve (AUC) was the primary measure. After the planned analysis for the initial algorithm A, we performed another set of exploratory analyses for an improved algorithm B. Results: Of 184 patients who agreed to participate in the study, 151 were finally analyzed.Hemodynamically significant lesions were observed in 79 patients (52.3%). The AUC was 0.71 (95% confidence interval [CI], 0.63–0.80) for CCTA, 0.65 (95% CI, 0.56–0.74) for CT-FFR algorithm A (P = 0.866), and 0.78 (95% CI, 0.70–0.86) for algorithm B (P = 0.112). Diagnostic accuracy was 0.63 (0.55–0.71) for CCTA alone, 0.66 (0.58–0.74) for algorithm A, and 0.76 (0.68–0.82) for algorithm B. Conclusion This study suggests the feasibility of automated CT-FFR, which can be performed on-site within several hours. However, the diagnostic performance of the current algorithm does not meet the a priori criteria for superiority. Future research is required to improve the accuracy.

Purpose: To establish a prospective registry for the active surveillance (AS) of prostate cancer (PC) using the Korean Urological Oncology Society (KUOS) database and to present interim analysis. Materials and Methods: The KUOS registry of AS for PC (KUOS-AS-PC) was organized in May 2019 and comprises multiple institutions nationwide. The eligibility criteria were as follows: patients with (1) pathologically proven PC; (2) pre-biopsy prostate-specific antigen (PSA) ≤20 ng/mL; (3) International Society of Urological Pathology (ISUP) grade 1 or 2 (no cribriform pattern 4); (4) clinical T stage ≤T2c; (5) positive core ratio ≤50%; and (6) maximal cancer involvement in the core ≤50%.Detailed longitudinal clinical information, including multi-parametric magnetic resonance imaging and disease-specific outcomes, was recorded. Results: From May 2019 to June 2021, 296 patients were enrolled, and 284 were analyzed. The mean±standard deviation (SD) age at enrollment was 68.7±8.2 years. The median follow-up period was 11.2 months (5.9–16.8 mo). Majority of patients had pre-biopsy PSA ≤10 ng/mL (91.2%), PSA density <0.2 ng/mL 2 (79.7%), ISUP grade group 1 (94.4%), single positive core (65.7%), maximal cancer involvement in the core ≤20% (78.1%), and clinical T stage of T1c or lower (72.9%). Fifty-two (18.3%) discontinued AS for various reasons. Interventions included radical prostatectomy (80.8%), transurethral prostatectomy (5.8%), primary androgen deprivation therapy (5.8%), radiation (5.8%), and focal therapy (1.9%). The mean±SD time to intervention was 8.9±5.2 months. The reasons for discontinuation included pathologic reclassification (59.6%), patient preference (25.0%), and radiologic reclassification (9.6%). Two (4.8%) patients with pathologic Gleason score upgraded to ISUP grade group 4, no biochemical recurrence. Conclusions The KUOS established a successful prospective database of PC patients undergoing AS in Korea, named the KUOS-AS-PC registry.

Purpose: Breast cancer is mainly diagnosed using core needle biopsy (CNB), although other biopsy methods, including vacuum-assisted biopsy (VAB), may also be used. We compared differences in clinical characteristics and prognoses of patients with breast cancer according to biopsy methods used for diagnosis. Methods: A total of 98,457 patients who underwent various biopsy methods (CNB, fine-needle aspiration [FNA], VAB, and excisional biopsy) for diagnosing breast cancer were recruited. Using CNB as a reference, related clinicopathological factors and prognostic differences between biopsy methods were analyzed retrospectively using large-scale data from the Korean Breast Cancer Society Registration System. The associations between biopsy methods and clinicopathological factors were compared using multinomial logistic regression analysis, and the prognoses of patients undergoing the different biopsy methods, as breast cancer-specific survival (BCSS) and overall survival (OS), were compared using the Kaplan-Meier method and Cox proportional hazard model. Results: Univariate and multivariate analyses showed that unlike FNA, both VAB and excisional biopsy were significantly associated with tumor size, palpability, tumor stage, and histologic grade as relatively good prognostic factors compared to CNB. In particular, VAB showed lower odds ratios for these factors than excisional biopsy. In the univariate analysis, the prognosis of patients undergoing VAB was better than that of those undergoing CNB with respect to BCSS (hazard ratio [HR], 0.188, p < 0.001) and OS (HR, 0.359; p < 0.001). However, in the multivariate analysis, there were no significant prognostic differences from CNB in both BCSS and OS; differences were only evident for FNA. Conclusion In this study, we showed that the characteristics of breast cancer differed according to various biopsy methods. Although VAB is not a standard method for breast cancer diagnosis, it showed no prognostic differences to CNB.

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.