Purpose: The accurate localization of bifurcation points in the brain near the circle of Willis is essential for labeling cerebral arteries and detecting potential aneurysms. Studies on the development of segmentation-based landmark localization methods for cerebral angiography are lacking. This study aimed to develop and validate a method for localizing anatomical landmarks using a three-dimensional (3D) encoder-decoder deep convolutional neural network architecture. Materials and Methods: Time-of-flight magnetic resonance angiography (MRA) images of 224 subjects obtained from publicly available datasets were used. Ten anatomical landmark points were annotated, and four different landmark subset configurations were trained and validated. For each configuration, 3D U-Net-based models were developed using the MRA images and their corresponding annotated landmarks. The deep learning prediction results were evaluated in terms of landmark localization errors. Results: Among the four configurations, the configuration with five landmark subsets produced the smallest landmark localization errors in the test dataset. Post-processing of the U-Net-predicted segmentation masks further reduced the mean localization errors across all landmark points for the configuration with five subsets. Conclusion The proposed landmark localization method effectively identified major anatomical landmarks around the circle of Willis and showed the potential to automate segmental analyses of intracranial arterial tortuosity.

Purpose: While the benefit of neoadjuvant chemotherapy (NAC) has been established in human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancers, its effectiveness in achieving pathological complete response (pCR) and optimal patient selection in estrogen receptor (ER)-positive, HER2-negative breast cancers remain less clearly defined. This study aimed to identify immunohistochemistry (IHC)-based predictors of pCR and to develop a scoring model for ER-strong positive/HER2-negative breast cancer. Methods: Data from a prospective cohort were retrospectively analyzed. We included 522 patients with ER-strong positive/HER2-negative tumors who received NAC and surgery between 2008 and 2021. IHC markers including progesterone receptor (PR), Ki-67, epidermal growth factor receptor (EGFR), cytokeratin 5/6 (CK5/6), and p53 were evaluated to identify predictors of pCR. Independent predictors of pCR from multivariate logistic regression were used to develop a weighted 4-point model. Model performance was assessed using receiver operating characteristic analysis. The prognostic impact of pCR was evaluated using KaplanMeier and Cox regression analyses. Results: Independent predictors of pCR included PR-negative status, positivity for basallike markers (EGFR or CK5/6), and Ki-67 ≥ 50%. The scoring model demonstrated good discrimination for pCR (area under the curve = 0.754). pCR rates increased stepwise, with scores of 4.9% (low), 10.7% (intermediate), and 36.2% (high). In the high-score group, pCR was significantly associated with improved disease-free survival (hazard ratio [HR], 0.09; p = 0.023) and distant metastasis-free survival (HR, 0.11; p = 0.035), whereas no significant survival differences according to pCR status were observed in the low and intermediate score groups. Conclusion This IHC-based model predicts pCR and helps identify subgroups in which pCR is associated with meaningful survival benefit following NAC in ER-positive/HER2-negative breast cancers. High-scoring patients may benefit from NAC, while patients with low- or intermediatescores may be better managed with surgery and endocrine therapy. This model may support personalized treatment decisions regarding NAC.

Objective: Since its development in 2002 by the Korean College of Neuropsychopharmacology and the Korean Society for Affective Disorders, the Korean Medication Algorithm Project for Depressive Disorder (KMAP-DD) has undergone five revisions. Methods: To improve survey efficiency, reflect general clinical practice, and facilitate comparisons with previous KMAP-DD revisions, the overall structure of the questionnaire was retained. The six sections of the questionnaire were as follows:1) pharmacological treatment strategies for major depressive disorder with and without psychotic features; 2) pharmacological treatment strategies for persistent depressive disorder and other depressive disorder subtypes; 3) consensus on treatment-resistant depression; 4) selection of an antidepressant in consideration of safety, adverse effects, and comorbid physical conditions; 5) treatment strategies for special populations (children/adolescents, elderly, and women); and 6) non-pharmacological biological therapies. First-, second-, and third-line treatment recommendations were statistically derived. Results: Compared to KMAP-DD 2021, only minor changes were noted, due to the limited introduction of new medications or treatment modalities. Nonetheless, notable shifts included an increased preference for atypical antipsychotics (AAPs), and higher preference of combination strategies involving AAPs and mood stabilizers, indicating a more proactive and intensive treatment trend in Korea. Conclusion KMAP-DD is expected to serve as a valuable clinical resource by providing expert consensus-based recommendations on specific treatment strategies and pharmacological options for major depressive disorders, thereby supporting the integration of real-world clinical practice with evidence-based medicine.

Objective: We evaluated the pharmacokinetics, tissue concentrations, and toxicities of belotecan during rotational intraperitoneal pressurized aerosol chemotherapy (RIPAC) in pigs. Methods: We sprayed belotecan in 10% and 30% of doses for intravenous chemotherapy in six pigs (cohort 1, n=3, 0.50 mg/m2 ; cohort 2, n=3, 1.5 mg/m2 ). We evaluated the time-dependent plasma concentrations of belotecan before RIPAC to 120 hours for the pharmacokinetics, tissue concentrations in twelve peritoneal regions, and hepatic and renal functions before RIPAC to 120 hours in the 2 cohorts. Results: Mean values of the peak plasma concentration (Cmax ), the time to Cmax , the time taken for Cmax to drop in half, and the area under the curve from time zero to the time of last quantifiable concentration were 905 and 3,700 ng/mL, 1.42 and 1.50 hours, 3.64 and 5.60 hours, and 2,260 and 17,900 pg·hr/mL in cohorts 1 and 2, respectively. Mean values of tissue concentrations were 1.5 to 15.3 times higher in cohort 1 than in cohort 2 despite the similar ratio of tissue to plasma concentration, and tissue concentrations in the two cohorts were higher in the parietal peritoneum than in the visceral peritoneum. However, hepatic and renal functions were not different before RIPAC to 120 hours in the two cohorts. Conclusion RIPAC using belotecan of 0.5 mg/m2 and 1.5 mg/m2 may be feasible with fewer hepatic and renal toxicities in pigs. Thus, belotecan of 1.5 mg/m2 may be considered as the starting dose for RIPAC in a phase 1 trial.

Purpose: Vascular endothelial growth factor tyrosine kinase inhibitors (TKIs) have been the standard of care for advanced and metastatic clear cell renal cell carcinoma (ccRCC). However, the therapeutic effect of TKI monotherapy remains unsatisfactory given the high rates of acquired resistance to TKI therapy despite favorable initial tumor response. Materials and Methods: To define the TKI-resistance mechanism and identify new therapeutic target for TKI-resistant ccRCC, an integrative differential gene expression analysis was performed using acquired resistant cohort and a public dataset. Sunitinib-resistant RCC cell lines were established and used to test their malignant behaviors of TKI resistance through in vitro and in vivo studies. Immunohistochemistry was conducted to compare expression between the tumor and normal kidney and verify expression of pathway-related proteins. Results: Integrated differential gene expression analysis revealed increased interferon-induced transmembrane protein 3 (IFITM3) expression in post-TKI samples. IFITM3 expression was increased in ccRCC compared with the normal kidney. TKI-resistant RCC cells showed high expression of IFITM3 compared with TKI-sensitive cells and displayed aggressive biologic features such as higher proliferative ability, clonogenic survival, migration, and invasion while being treated with sunitinib. These aggressive features were suppressed by the inhibition of IFITM3 expression and promoted by IFITM3 overexpression, and these findings were confirmed in a xenograft model. IFITM3-mediated TKI resistance was associated with the activation of TRAF6 and MAPK/AP-1 pathways. Conclusions These results demonstrate IFITM3-mediated activation of the TRAF6/MAPK/AP-1 pathways as a mechanism of acquired TKI resistance, and suggest IFITM3 as a new target for TKI-resistant ccRCC.

Purpose: This study investigated the efficacy of intravesical gemcitabine as an alternative to bacillus Calmette–Guérin (BCG) therapy. Materials and Methods: Data were retrospectively collected across seven institutions from February 1999 to May 2023. Inclusion criteria included patients with intermediate- or high-risk non-muscle invasive bladder cancer (NMIBC) who underwent transurethral resection of bladder tumors (TURBT) and received at least four sessions of intravesical gemcitabine or BCG induction therapy. Patient characteristics, complete remission (CR), occurrence, and progression rates were compared. Results: In total, 149 patients were included in this study (gemcitabine, 63; BCG, 86). No differences were apparent between the two groups in baseline characteristics, except for the follow-up period (gemcitabine, 9.2±5.9 months vs. BCG, 43.9±41.4 months, p<0.001). There were no consistent significant differences observed between the two groups in the 3-month (gemcitabine, 98.4% vs. BCG, 95.3%; p=0.848), 6-month (94.9% vs. 90.0%, respectively; p=0.793) and 1-year CR rates (84.2% vs. 83.3%, respectively;p=0.950). Also, there was no significant statistical difference in progression-free survival between the two groups (p=0.953). The occurrence rates of adverse events were similar between the groups (22.2% vs. 22.1%; p=0.989); however, the rate of Clavien– Dindo grade 2 or higher was significantly higher in the BCG group (1.6% vs. 16.3%, respectively; p<0.001). Conclusions Intravesical gemcitabine demonstrated efficacy comparable to BCG therapy for the first year in patients with intermediate- and high-risk NMIBC. However, long-term follow-up studies are warranted.

Postmortem computed tomography (PMCT) is used in forensic medicine worldwide due to its ability to non-invasively visualize injuries, hemorrhage, and estimate volume. In the autopsy of infants, assessing nutritional conditions such as weight is crucial for identifying neglect. This study aims to evaluate the usefulness of retrospectively estimating the weight of Korean infants using PMCT-based volume and multiplication factors, even when the body has been cremated. A total of 44 cases of infant death (under 12 months) were analyzed. PMCT images were obtained before autopsy. Autopsy records and documentation provided by the police at the time of autopsy were reviewed to determine the weight (g) of the infant. PMCT-based infant volumes (mL) were estimated using a three-dimensional semi-automatic segmentation method. Multiplication factors (g/mL) were calculated by dividing the weight recorded at autopsy by the PMCT-based volume, yielding a mean of 1.047 g/mL, ranging from 1.014 g/mL to 1.085 g/mL. The mean absolute error compared to weights recorded at autopsy was 95 g. Significant discrepancies were observed between weights recorded at the scene or medical center and those measured at autopsy. This study demonstrates that PMCT-based weight estimation for Korean infants is a reliable method and has the potential for retrospectively validating incorrect weight measurements and addressing inconsistencies in recorded weight data.

Background and Objectives: Peritonsillar abscess (PTA) is an accumulation of pus between the palatine tonsil and pharyngeal constrictor muscle. It is a common cause of emergency on-call consultations among ENT doctors and occurs due to the possibility of sepsis, airway obstruction, and progression to deep neck infection. This study aims to compare the effectiveness of needle aspiration (NA) to incision & drainage (I&D) for the treatment of PTA.Subjects and Method From September 2018 to March 2020, 58 patients with PTA were admitted to our ENT Department. After a comprehensive diagnostic procedure, 38 patients were enrolled in the study and they underwent either I&D (20 patients) or NA (18 patients) treatment. Patients were discharged when edema decreased on the endoscopic findings and their symptoms improved, with a visual analogue scale (VAS) score <3 points. For each patient, we evaluated the abscess volume, age, body mass index, hypertension, diabetes mellitus, smoking and drinking history, abscess size, and duration of hospitalization. White blood cell (WBC) count, C-reactive protein (CRP) level, and erythrocyte sedimentation rate (ESR) were estimated on the 1st, 3rd, and 5th days of hospitalization. Results: The mean age of participants was 42.8±15.5 years and 40.3±14.7 years in the I&D and NA groups, respectively. Except for ESR, the mean hospitalization duration, initial volume of abscess size, VAS pain score, WBC count and the CRP level were not different between the groups. Conclusion Our study revealed no significant differences in hospital stay duration, VAS score, WBC counts or in the CRP level among patients admitted for PTA, whether they underwent I&D or NA.

Objective: Clozapine is considered the most reliable drug for treatment-resistant schizophrenia. In 2014, a generic formulation of clozapine (Clzapine) was introduced in Korea. This study was performed to provide clinical information regarding the use of clozapine and to compare efficacy and tolerability when converting from the brand-name formulation (Clozaril) to the generic formulation during longterm maintenance treatment among Korean patients with schizophrenia. Methods: This mirror-image study retrospectively investigated the electronic medical records of patients who had switched from Clozaril to Clzapine with a ≥1-year duration for each formulation. Clinical data were collected, including information regarding clozapine use, psychiatric hospitalization, co-medications, and blood test findings. Data before and after the switch were compared using paired t-tests. Results: Among 332 patients, the mean 1-year dosages were 233.32±149.35 mg/day for Clozaril and 217.36±136.66 mg/day for Clzapine. The mean clozapine concentration-to-dose ratios were similar before and after the switch (Clozaril, 1.33±0.68; Clzapine, 1.26±0.80). Switching from Clozaril to Clzapine resulted in no significant differences in the hospitalization rate, hospitalization duration, or laboratory findings (liver function parameters, serum cholesterol level, and serum glucose level). Equivalent doses of co-prescribed antidepressants were decreased, but concomitant medications otherwise showed no significant differences. Conclusion Clinical efficacy and tolerability appear comparable when switching to Clzapine during clozapine maintenance treatment. This study offers descriptive real-world clinical insights into clozapine maintenance treatment in Korea, thereby providing patients with more treatment options and contributing to the development of maintenance guidelines tailored to the Korean population.

Rare endocrine diseases are complex conditions that require lifelong specialized care due to their chronic nature and associated long-term complications. In Korea, a lack of nationwide data on clinical practice and outcomes has limited progress in patient care. Therefore, the Multicenter Networks for Ideal Outcomes of Pediatric Rare Endocrine and Metabolic Disease (OUTSPREAD) study was initiated. This study involves 30 centers across Korea. The study aims to improve the long-term prognosis of Korean patients with rare endocrine diseases by collecting comprehensive clinical data, biospecimens, and patient-reported outcomes to identify complications and unmet needs in patient care. Patients with childhood-onset pituitary, adrenal, or gonadal disorders, such as craniopharyngioma, congenital adrenal hyperplasia (CAH), and Turner syndrome were prioritized. The planned enrollment is 1,300 patients during the first study phase (2022–2024). Clinical, biochemical, and imaging data from diagnosis, treatment, and follow-up during 1980–2023 were retrospectively reviewed. For patients who agreed to participate in the prospective cohort, clinical data and biospecimens will be prospectively collected to discover ideal biomarkers that predict the effectiveness of disease control measures and prognosis. Patient-reported outcomes, including quality of life and depression scales, will be evaluated to assess psychosocial outcomes. Additionally, a substudy on CAH patients will develop a steroid hormone profiling method using liquid chromatography-tandem mass spectrometry to improve diagnosis and monitoring of treatment outcomes. This study will address unmet clinical needs by discovering ideal biomarkers, introducing evidence-based treatment guidelines, and ultimately improving long-term outcomes in the areas of rare endocrine and metabolic diseases.