Purpose: Radiotherapy is used to reduce the risk of breast cancer recurrence after surgery, but it is a potential cause of secondary cancer. We validated the risk of secondary cancer in primary breast cancer who received radiotherapy compared with those who did not from a matched cohort using a large-scale observational study of the Observational Health Data Sciences and Informatics (OHDSI) data network. Materials and Methods: A retrospective comparative cohort study using propensity score-matched cohorts was performed using two Observational Medical Outcome Partnership common data model databases, from tertiary general hospitals in South Korea. Among female patients who underwent surgery after the diagnosis of breast cancer, the risk of secondary primary malignant occurrence after 1:1 matching was analyzed. Results: Among 27,078 patients with breast cancer, there was no significant difference in the risk of secondary cancer following radiotherapy in 4,426 patients after 1:1 propensity-score matching. Further, there were no significant differences in the sensitivity analysis according to age, latency period, and number of radiation treatments. Conclusion There was no difference in the risk of secondary cancer in the patients diagnosed with breast cancer depending on whether or not radiotherapy was performed after surgery. In the future, it is necessary to analyze including data generated during cancer treatment.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Vertebral arteriovenous fistula (VAVF) is a rare lesion characterized by an abnormal connection between the extracranial vertebral artery and the surrounding venous plexus. It typically arises due to penetrating injury, although it can occasionally result from blunt trauma. Brachial plexus injury (BPI) is also infrequently associated with VAVF. We present a rare case of VAVF caused by blunt trauma, which resulted in BPI. The patient, who had previously sustained a C2 fracture and C2–3 myelopathy from a bicycle accident, presented with new-onset weakness in the right upper extremity. His previous clinical history led to an initial suspicion of either an exacerbation of a pre-existing lesion or a shoulder injury. However, electromyography indicated that the weakness was due to BPI. Further evaluations later revealed VAVF to be the primary cause of the BPI. VAVF must be recognized as a rare potential reason for BPI, as timely intervention is essential for improving patient recovery and prognosis.

Background: Emergency department (ED) overcrowding poses a global challenge, particularly for critically ill patients requiring intensive care unit (ICU) admission. Although delays in ICU transfer increase mortality in critically ill populations, the optimal timing for septic shock remains uncertain. Methods: We conducted a target trial emulation using a prospective cohort of 815 septic shock patients from 19 Korean hospitals. Delayed ICU transfer was defined using restricted cubic splines. The primary outcome was in-hospital mortality. Multivariable logistic regression and inverse probability treatment weighting were used to adjust for confounders of age, sex, comorbidities, severity of illness, and mechanical ventilation use. Subgroup analyses were performed to assess the effect across patient characteristics. Results: The median time of ED-to-ICU transfer was 6.7 hours (interquartile range, 4.7–11.4), and only 7% of patients were transferred within 3 hours. ICU transfer within 3 hours was associated with significantly lower in-hospital mortality (odds ratio, 0.48; 95% CI, 0.24–0.94) compared to later transfers. Mortality risk increased with elapsing time up to 6 hours and then plateaued. The benefit of early ICU transfer was consistent across subgroups but was particularly pronounced in patients requiring extracorporeal membrane oxygenation or continuous renal replacement therapy (P for interaction=0.02). Conclusions Early ICU transfer within 3 hours significantly reduces mortality in patients with septic shock, with the greatest benefit observed in those requiring advanced organ support. These findings highlight the need for system-wide strategies to reduce ED boarding time and prioritize timely ICU admission for septic shock management.

The process of cancer metastasis is dependent on the cancer cells’ capacity to detach from the primary tumor, endure in a suspended state, and establish colonies in other locations.Anchorage dependence, which refers to the cells’ reliance on attachment to the extracellular matrix (ECM), is a critical determinant of cellular shape, dynamics, behavior, and, ultimately, cell fate in nonmalignant and cancer cells. Anchorage-independent growth is a characteristic feature of cells resistant to anoikis, a programmed cell death process triggered by detachment from the ECM. This ability to grow and survive without attachment to a substrate is a crucial stage in the progression of metastasis. The recently discovered phenomenon named “adherent-to-suspension transition (AST)” alters the requirement for anchoring and enhances survival in a suspended state. AST is controlled by four transcription factors (IKAROS family zinc finger 1, nuclear factor erythroid 2, BTG anti-proliferation factor 2, and interferon regulatory factor 8) and can detach cells without undergoing the typical epithelialmesenchymal transition. Notably, AST factors are highly expressed in circulating tumor cells compared to their attached counterparts, indicating their crucial role in the spread of cancer.Crucially, the suppression of AST substantially reduces metastasis while sparing primary tumors. These findings open up possibilities for developing targeted therapies that inhibit metastasis and emphasize the importance of AST, leading to a fundamental change in our comprehension of how cancer spreads.

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.

Background: Current international guidelines recommend against deep sedation as it is associated with worse outcomes in the intensive care unit (ICU). However, in Korea the prevalence of deep sedation and its impact on patients in the ICU are not well known. Methods: From April 2020 to July 2021, a multicenter, prospective, longitudinal, noninterventional cohort study was performed in 20 Korean ICUs. Sedation depth extent was divided into light and deep using a mean Richmond Agitation–Sedation Scale value within the first 48 hours. Propensity score matching was used to balance covariables; the outcomes were compared between the two groups. Results: Overall, 631 patients (418 [66.2%] and 213 [33.8%] in the deep and light sedation groups, respectively) were included. Mortality rates were 14.1% and 8.4% in the deep and light sedation groups (P = 0.039), respectively. Kaplan-Meier estimates showed that time to extubation (P < 0.001), ICU length of stay (P = 0.005), and death P = 0.041) differed between the groups. After adjusting for confounders, early deep sedation was only associated with delayed time to extubation (hazard ratio [HR], 0.66; 95% confidence inter val [CI], 0.55– 0.80; P < 0.001). In the matched cohort, deep sedation remained significantly associated with delayed time to extubation (HR, 0.68; 95% 0.56–0.83; P < 0.001) but was not associated with ICU length of stay (HR, 0.94; 95% CI, 0.79–1.13; P = 0.500) and in-hospital mortality (HR, 1.19; 95% CI, 0.65–2.17; P = 0.582). Conclusion In many Korean ICUs, early deep sedation was highly prevalent in mechanically ventilated patients and was associated with delayed extubation, but not prolonged ICU stay or in-hospital death.

Purpose: To provide a wider choice of treatment opportunities for patients with neuroendocrine tumor (NET) in Korea, we have conducted a phase 1, open-label, single-arm, dose-escalation study of SNU-KB-01, a no-carrier added (NCA) 177Lu-labeled DOTATATE. Materials and Methods: Seven patients with inoperable, progressive, metastatic, or locally advanced, somatostatin receptor-positive NET with Ki67 index ≤ 20% were enrolled according to the rolling six design. The study consisted of two cohorts to receive 4 cycles of SNU-KB-01 every 8 weeks for the first dose of 5.55 GBq (n=3) and 7.40 GBq (n=4). We assessed the incidence of dose-limiting toxicity (DLT) and adverse event, absorbed dose of kidneys and bone marrow, and objective tumor response. Results: Seven patients completed 4 cycles (21.3-30.1 GBq total dose) of SNU-KB-01. The mean absorbed doses to kidneys and bone marrow were 0.500 mGy/MBq and 0.053 mGy/MBq, respectively, and the total body effective dose was 0.115 mSv/MBq. No DLT was observed and the maximum tolerated dose was 7.40 GBq/cycle. Grade 3 thrombocytopenia occurred in one patient, but no other grade 3 or 4 major hematologic or renal toxicity was observed. The best objective response to SNU-KB-01 was partial response. Overall response rate was 42.9% and disease control rate was 85.7%. Conclusion Treatment with 4 cycles of SNU-KB-01 was well tolerated and resulted in control of disease in most of the patients. Our results indicate SNU-KB-01, an NCA 177Lu-labeled DOTATATE, as a potentially safe and efficacious treatment option for NET patients in Korea.

Objective: To analyze the changes in muscle mass and quality with time on the paretic and non-paretic sides in subacute stroke patients and identify correlations between the variation of muscle mass and quality and lower limb functions. Methods: Thirty hemiplegia patients diagnosed with stroke participated in this study. To evaluate poststroke muscle changes, longitudinal measurement of muscle mass and quality was conducted with bilateral lower limbs. The elastic shear modulus was measured using shear wave elastography and muscle thickness (MT) of rectus femoris, vastus intermedius, vastus lateralis (VL), vastus medialis, tibialis anterior, and gastrocnemius (GCM) muscles. Functional evaluation was performed using Berg Balance Scale (BBS), Five Times Sit to Stand Test (FTSST). Follow-up was performed at discharge. The muscle mass and quality were compared according to time. We analyzed whether muscle quantity and quality were related to function. Results: MT demonstrated no significant change with time. The elastic shear modulus increased significantly in the paretic VL and GCM muscles and did not change significantly in the muscles on the non-paretic side. Correlation analysis detected that elastic shear modulus in the VL has a cross-sectional negative relationship between BBS and positive relationship between FTSST. There were significant correlation between variation of FTSST and the variation of the elastic shear modulus in VL. Conclusion Only paretic VL and GCM muscle quality changed in subacute stroke patients and muscle’s property related to lower limb functions. Therefore, the lower extremity requires an approach to muscle quality rather than quantity for subacute stroke patients.

Kennedy’s disease (KD) or bulbospinal muscular atrophy is an uncommon x-linked recessive genetic disorder. Its diagnosis is challenging due to its wide array of clinical manifestations and difficulty distinguishing it from other motor neuron diseases.Thus, diagnosis is confirmed through DNA testing. 52-year-old male patient presented to the hospital with chronic low back pain (LBP) and muscle weakness. The patient had mild weakness in some proximal muscles, increased deep tendon reflex.Lumbar spine magnetic resonance imaging (MRI) showed degenerative changes. Motor nerve conduction test results showed close to the normal. Sensory nerve conduction test results showed decreased latency and amplitude in most nerves. Needle electromyography revealed fasciculation potentials, diffuse fibrillation potentials, and positive sharp waves were detected. Thus, molecular genetic testing was performed. Consequently, KD was diagnosed. These results suggest the importance of detailed history taking and neurological examination even for patients with chronic LBP to rule out severe diseases.