Background: This study aims to investigate the trend of doctor shopping among patients with rotator cuff tear (RCT) before undergoing surgery and to examine the relevance of these findings to the public. Methods: A survey was conducted of 326 patients from 10 hospitals (male, 176; female, 150) who underwent arthroscopic rotator cuff repair (ARCR) for symptomatic RCT between September 2019 and February 2020. A questionnaire was used to obtain data regarding the type of medical care service, medical institutions visited before surgery, number of treatments received, and cost of treatment. Results: A total of 326 patients (87%) received treatment at least once at another medical institution before visiting the hospital where the surgery was performed. Patients visited an average of 9.4 health providers or physicians for shoulder pain before visiting the hospital where surgery was performed. Among the 326 patients, 148 (45%) visited more than two medical institutions and spent an average of 641,983 Korean won (KRW; $466, 50,000–5,000,000 KRW) before surgery. Medical expenses before surgery were proportional to the number of medical institutions visited (P=0.002), symptom duration (P=0.002), and initial visual analog scale (VAS) pain score (P=0.007) but were not associated with sex, age, VAS pain score immediately before surgery, or RCT size. Conclusions Medical expense before ARCR was associated with the severity of preoperative pain and duration of symptoms. After onset of shoulder symptoms, patients should visit as soon as possible a hospital that has surgeons who specialize in shoulder repair to prevent unnecessary medical expense and proper treatment.Level of evidence: IV.

Background: This study aims to investigate the trend of doctor shopping among patients with rotator cuff tear (RCT) before undergoing surgery and to examine the relevance of these findings to the public. Methods: A survey was conducted of 326 patients from 10 hospitals (male, 176; female, 150) who underwent arthroscopic rotator cuff repair (ARCR) for symptomatic RCT between September 2019 and February 2020. A questionnaire was used to obtain data regarding the type of medical care service, medical institutions visited before surgery, number of treatments received, and cost of treatment. Results: A total of 326 patients (87%) received treatment at least once at another medical institution before visiting the hospital where the surgery was performed. Patients visited an average of 9.4 health providers or physicians for shoulder pain before visiting the hospital where surgery was performed. Among the 326 patients, 148 (45%) visited more than two medical institutions and spent an average of 641,983 Korean won (KRW; $466, 50,000–5,000,000 KRW) before surgery. Medical expenses before surgery were proportional to the number of medical institutions visited (P=0.002), symptom duration (P=0.002), and initial visual analog scale (VAS) pain score (P=0.007) but were not associated with sex, age, VAS pain score immediately before surgery, or RCT size. Conclusions Medical expense before ARCR was associated with the severity of preoperative pain and duration of symptoms. After onset of shoulder symptoms, patients should visit as soon as possible a hospital that has surgeons who specialize in shoulder repair to prevent unnecessary medical expense and proper treatment.Level of evidence: IV.

Background: This study aims to investigate the trend of doctor shopping among patients with rotator cuff tear (RCT) before undergoing surgery and to examine the relevance of these findings to the public. Methods: A survey was conducted of 326 patients from 10 hospitals (male, 176; female, 150) who underwent arthroscopic rotator cuff repair (ARCR) for symptomatic RCT between September 2019 and February 2020. A questionnaire was used to obtain data regarding the type of medical care service, medical institutions visited before surgery, number of treatments received, and cost of treatment. Results: A total of 326 patients (87%) received treatment at least once at another medical institution before visiting the hospital where the surgery was performed. Patients visited an average of 9.4 health providers or physicians for shoulder pain before visiting the hospital where surgery was performed. Among the 326 patients, 148 (45%) visited more than two medical institutions and spent an average of 641,983 Korean won (KRW; $466, 50,000–5,000,000 KRW) before surgery. Medical expenses before surgery were proportional to the number of medical institutions visited (P=0.002), symptom duration (P=0.002), and initial visual analog scale (VAS) pain score (P=0.007) but were not associated with sex, age, VAS pain score immediately before surgery, or RCT size. Conclusions Medical expense before ARCR was associated with the severity of preoperative pain and duration of symptoms. After onset of shoulder symptoms, patients should visit as soon as possible a hospital that has surgeons who specialize in shoulder repair to prevent unnecessary medical expense and proper treatment.Level of evidence: IV.

Background: This study aims to investigate the trend of doctor shopping among patients with rotator cuff tear (RCT) before undergoing surgery and to examine the relevance of these findings to the public. Methods: A survey was conducted of 326 patients from 10 hospitals (male, 176; female, 150) who underwent arthroscopic rotator cuff repair (ARCR) for symptomatic RCT between September 2019 and February 2020. A questionnaire was used to obtain data regarding the type of medical care service, medical institutions visited before surgery, number of treatments received, and cost of treatment. Results: A total of 326 patients (87%) received treatment at least once at another medical institution before visiting the hospital where the surgery was performed. Patients visited an average of 9.4 health providers or physicians for shoulder pain before visiting the hospital where surgery was performed. Among the 326 patients, 148 (45%) visited more than two medical institutions and spent an average of 641,983 Korean won (KRW; $466, 50,000–5,000,000 KRW) before surgery. Medical expenses before surgery were proportional to the number of medical institutions visited (P=0.002), symptom duration (P=0.002), and initial visual analog scale (VAS) pain score (P=0.007) but were not associated with sex, age, VAS pain score immediately before surgery, or RCT size. Conclusions Medical expense before ARCR was associated with the severity of preoperative pain and duration of symptoms. After onset of shoulder symptoms, patients should visit as soon as possible a hospital that has surgeons who specialize in shoulder repair to prevent unnecessary medical expense and proper treatment.Level of evidence: IV.

Background: It is well known that a large number of patients with diabetes also have dyslipidemia, which significantly increases the risk of cardiovascular disease (CVD). This study aimed to evaluate the efficacy and safety of combination drugs consisting of metformin and atorvastatin, widely used as therapeutic agents for diabetes and dyslipidemia. Methods: This randomized, double-blind, placebo-controlled, parallel-group and phase III multicenter study included adults with glycosylated hemoglobin (HbA1c) levels >7.0% and <10.0%, low-density lipoprotein cholesterol (LDL-C) >100 and <250 mg/dL. One hundred eighty-five eligible subjects were randomized to the combination group (metformin+atorvastatin), metformin group (metformin+atorvastatin placebo), and atorvastatin group (atorvastatin+metformin placebo). The primary efficacy endpoints were the percent changes in HbA1c and LDL-C levels from baseline at the end of the treatment. Results: After 16 weeks of treatment compared to baseline, HbA1c showed a significant difference of 0.94% compared to the atorvastatin group in the combination group (0.35% vs. −0.58%, respectively; P<0.0001), whereas the proportion of patients with increased HbA1c was also 62% and 15%, respectively, showing a significant difference (P<0.001). The combination group also showed a significant decrease in LDL-C levels compared to the metformin group (−55.20% vs. −7.69%, P<0.001) without previously unknown adverse drug events. Conclusion The addition of atorvastatin to metformin improved HbA1c and LDL-C levels to a significant extent compared to metformin or atorvastatin alone in diabetes and dyslipidemia patients. This study also suggested metformin’s preventive effect on the glucose-elevating potential of atorvastatin in patients with type 2 diabetes mellitus and dyslipidemia, insufficiently controlled with exercise and diet. Metformin and atorvastatin combination might be an effective treatment in reducing the CVD risk in patients with both diabetes and dyslipidemia because of its lowering effect on LDL-C and glucose.

Background: Atherogenic dyslipidemia, which is frequently associated with type 2 diabetes (T2D) and insulin resistance, contributes to the development of vascular complications. Statin therapy is the primary approach to dyslipidemia management in T2D, however, the role of non-statin therapy remains unclear. Ezetimibe reduces cholesterol burden by inhibiting intestinal cholesterol absorption. Fibrates lower triglyceride levels and increase high-density lipoprotein cholesterol (HDL-C) levels via peroxisome proliferator- activated receptor alpha agonism. Therefore, when combined, these drugs effectively lower non-HDL-C levels. Despite this, few clinical trials have specifically targeted non-HDL-C, and the efficacy of triple combination therapies, including statins, ezetimibe, and fibrates, has yet to be determined. Methods: This is a multicenter, prospective, randomized, open-label, active-comparator controlled trial involving 3,958 eligible participants with T2D, cardiovascular risk factors, and elevated non-HDL-C (≥100 mg/dL). Participants, already on moderate-intensity statins, will be randomly assigned to either Ezefeno (ezetimibe/fenofibrate) addition or statin dose-escalation. The primary end point is the development of a composite of major adverse cardiovascular and diabetic microvascular events over 48 months. Conclusion This trial aims to assess whether combining statins, ezetimibe, and fenofibrate is as effective as, or possibly superior to, statin monotherapy intensification in lowering cardiovascular and microvascular disease risk for patients with T2D. This could propose a novel therapeutic approach for managing dyslipidemia in T2D.

Purpose: Advances in chemotherapeutic and targeted agents have increased pathologic complete response (pCR) rates after neoadjuvant systemic therapy (NST). Vacuum-assisted biopsy (VAB) has been suggested to accurately evaluate pCR. This study aims to confirm the non-inferiority of the 5-year disease-free survival of patients who omitted breast surgery when predicted to have a pCR based on breast magnetic resonance imaging (MRI) and VAB after NST, compared with patients with a pCR who had undergone breast surgery in previous studies. Methods The Omission of breast surgery for PredicTed pCR patients wIth MRI and vacuumassisted bIopsy in breaST cancer after neoadjuvant systemic therapy (OPTIMIST) trial is a prospective, multicenter, single-arm, non-inferiority study enrolling in 17 tertiary care hospitals in the Republic of Korea. Eligible patients must have a clip marker placed in the tumor and meet the MRI criteria suggesting complete clinical response (post-NST MRI size ≤ 1 cm and lesion-to-background signal enhancement ratio ≤ 1.6) after NST. Patients will undergo VAB, and breast surgery will be omitted for those with no residual tumor. Axillary surgery can also be omitted if the patient was clinically node-negative before and after NST and met the stringent criteria of MRI size ≤ 0.5 cm. Survival and efficacy outcomes are evaluated over five years.Discussion: This study seeks to establish evidence for the safe omission of breast surgery in exceptional responders to NST while minimizing patient burden. The trial will address concerns about potential undertreatment due to false-negative results and recurrence as well as improved patient-reported quality of life issues from the omission of surgery. Successful completion of this trial may reshape clinical practice for certain breast cancer subtypes and lead to a safe and less invasive approach for selected patients.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Purpose: Acute promyelocytic leukemia (APL) is a rare disease in children and there are some different characteristics between children and adult. We aimed to evaluate incidence, clinical characteristics and treatment outcomes of pediatric APL in Korea. Materials and Methods: Seventy-nine pediatric APL patients diagnosed from January 2009 to December 2016 in 16 tertiary medical centers in Korea were reviewed retrospectively. Results: Of 801 acute myeloid leukemia children, 79 (9.9%) were diagnosed with APL. The median age at diagnosis was 10.6 years (range, 1.3 to 18.0). Male and female ratio was 1:0.93. Thirty patients (38.0%) had white blood cell (WBC) count greater than 10×109/L at diagnosis. All patients received induction therapy consisting of all-trans retinoic acid and chemotherapy. Five patients (6.6%) died during induction chemotherapy and 66 patients (86.8%) achieved complete remission (CR) after induction chemotherapy. The causes of death were three intracranial hemorrhage, one cerebral infarction, and one sepsis. Five patients (7.1%) suffered a relapse during or after maintenance chemotherapy. The estimated 4-year event-free survival and overall survival (OS) rates were 82.1%±4.4%, 89.7%±5.1%, respectively. The 4-year OS was significantly higher in patients with initial WBC < 10×109/L than in those with initial WBC ≥ 10×109/L (p=0.020). Conclusion This study showed that the CR rates and survival outcomes in Korean pediatric APL patients were relatively good. The initial WBC count was the most important prognostic factor and most causes of death were related to serious bleeding in the early stage of treatment.