Background: s/Aims: Hepatocellular carcinoma (HCC) is the sixth most common cancer and second leading cause of cancer-related deaths in South Korea. This study evaluated the characteristics of Korean patients newly diagnosed with HCC in 2016-2018. Methods: Data from the Korean Primary Liver Cancer Registry (KPLCR), a representative database of patients newly diagnosed with HCC in South Korea, were analyzed. This study investigated 4,462 patients with HCC registered in the KPLCR in 2016-2018. Results: The median patient age was 63 years (interquartile range, 55-72). 79.7% of patients were male. Hepatitis B infection was the most common underlying liver disease (54.5%). The Barcelona Clinic Liver Cancer (BCLC) staging system classified patients as follows: stage 0 (14.9%), A (28.8%), B (7.5%), C (39.0%), and D (9.8%). The median overall survival was 3.72 years (95% confidence interval, 3.47-4.14), with 1-, 3-, and 5-year overall survival rates of 71.3%, 54.1%, and 44.3%, respectively. In 2016-2018, there was a significant shift toward BCLC stage 0-A and Child-Turcotte-Pugh liver function class A (P<0.05), although survival rates did not differ by diagnosis year. In the treatment group (n=4,389), the most common initial treatments were transarterial therapy (31.7%), surgical resection (24.9%), best supportive care (18.9%), and local ablation therapy (10.5%). Conclusions Between 2016 and 2018, HCC tended to be diagnosed at earlier stages, with better liver function in later years. However, since approximately half of the patients remained diagnosed at an advanced stage, more rigorous and optimized HCC screening strategies should be implemented.

Purpose: Recent development in perioperative treatment of resectable non–small cell lung cancer (NSCLC) have changed the landscape of early lung cancer management. The ADAURA trial has demonstrated the efficacy of adjuvant osimertinib treatment in resectable NSCLC patients; however, studies are required to show which subgroup of patients are at a high risk of relapse and require adjuvant epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment. This study evaluated risk factors for postoperative relapse among patients who underwent complete resection. Materials and Methods: Data were obtained from the Korean Association for Lung Cancer Registry (KALC-R), a database created using a retrospective sampling survey by the Korean Central Cancer Registry (KCCR) and the Lung Cancer Registration Committee. Results: A total of 3,176 patients who underwent curative resection was evaluated. The mean observation time was approximately 35.4 months. Among stage I to IIIA NSCLC patients, the EGFR-mutant subgroup included 867 patients, and 75.2%, 11.2%, and 11.8% were classified as stage I, stage II, and stage III, respectively. Within the EGFR-mutant subgroup, 44 (5.1%) and 121 (14.0%) patients showed early and late recurrence, respectively. Multivariate analysis on association with postoperative relapse among the EGFR-mutant subgroup showed that age, pathologic N and TNM stages, pleural invasion status, and surgery type were independent significant factors. Conclusion Among the population that underwent complete resection for early NSCLC with EGFR mutation, patients with advanced stage, pleural invasion, or limited resection are more likely to show postoperative relapse.

Purpose: Recent development in perioperative treatment of resectable non–small cell lung cancer (NSCLC) have changed the landscape of early lung cancer management. The ADAURA trial has demonstrated the efficacy of adjuvant osimertinib treatment in resectable NSCLC patients; however, studies are required to show which subgroup of patients are at a high risk of relapse and require adjuvant epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment. This study evaluated risk factors for postoperative relapse among patients who underwent complete resection. Materials and Methods: Data were obtained from the Korean Association for Lung Cancer Registry (KALC-R), a database created using a retrospective sampling survey by the Korean Central Cancer Registry (KCCR) and the Lung Cancer Registration Committee. Results: A total of 3,176 patients who underwent curative resection was evaluated. The mean observation time was approximately 35.4 months. Among stage I to IIIA NSCLC patients, the EGFR-mutant subgroup included 867 patients, and 75.2%, 11.2%, and 11.8% were classified as stage I, stage II, and stage III, respectively. Within the EGFR-mutant subgroup, 44 (5.1%) and 121 (14.0%) patients showed early and late recurrence, respectively. Multivariate analysis on association with postoperative relapse among the EGFR-mutant subgroup showed that age, pathologic N and TNM stages, pleural invasion status, and surgery type were independent significant factors. Conclusion Among the population that underwent complete resection for early NSCLC with EGFR mutation, patients with advanced stage, pleural invasion, or limited resection are more likely to show postoperative relapse.

Background: s/Aims: Hepatocellular carcinoma (HCC) is the sixth most common cancer and second leading cause of cancer-related deaths in South Korea. This study evaluated the characteristics of Korean patients newly diagnosed with HCC in 2016-2018. Methods: Data from the Korean Primary Liver Cancer Registry (KPLCR), a representative database of patients newly diagnosed with HCC in South Korea, were analyzed. This study investigated 4,462 patients with HCC registered in the KPLCR in 2016-2018. Results: The median patient age was 63 years (interquartile range, 55-72). 79.7% of patients were male. Hepatitis B infection was the most common underlying liver disease (54.5%). The Barcelona Clinic Liver Cancer (BCLC) staging system classified patients as follows: stage 0 (14.9%), A (28.8%), B (7.5%), C (39.0%), and D (9.8%). The median overall survival was 3.72 years (95% confidence interval, 3.47-4.14), with 1-, 3-, and 5-year overall survival rates of 71.3%, 54.1%, and 44.3%, respectively. In 2016-2018, there was a significant shift toward BCLC stage 0-A and Child-Turcotte-Pugh liver function class A (P<0.05), although survival rates did not differ by diagnosis year. In the treatment group (n=4,389), the most common initial treatments were transarterial therapy (31.7%), surgical resection (24.9%), best supportive care (18.9%), and local ablation therapy (10.5%). Conclusions Between 2016 and 2018, HCC tended to be diagnosed at earlier stages, with better liver function in later years. However, since approximately half of the patients remained diagnosed at an advanced stage, more rigorous and optimized HCC screening strategies should be implemented.

Purpose: Recent development in perioperative treatment of resectable non–small cell lung cancer (NSCLC) have changed the landscape of early lung cancer management. The ADAURA trial has demonstrated the efficacy of adjuvant osimertinib treatment in resectable NSCLC patients; however, studies are required to show which subgroup of patients are at a high risk of relapse and require adjuvant epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment. This study evaluated risk factors for postoperative relapse among patients who underwent complete resection. Materials and Methods: Data were obtained from the Korean Association for Lung Cancer Registry (KALC-R), a database created using a retrospective sampling survey by the Korean Central Cancer Registry (KCCR) and the Lung Cancer Registration Committee. Results: A total of 3,176 patients who underwent curative resection was evaluated. The mean observation time was approximately 35.4 months. Among stage I to IIIA NSCLC patients, the EGFR-mutant subgroup included 867 patients, and 75.2%, 11.2%, and 11.8% were classified as stage I, stage II, and stage III, respectively. Within the EGFR-mutant subgroup, 44 (5.1%) and 121 (14.0%) patients showed early and late recurrence, respectively. Multivariate analysis on association with postoperative relapse among the EGFR-mutant subgroup showed that age, pathologic N and TNM stages, pleural invasion status, and surgery type were independent significant factors. Conclusion Among the population that underwent complete resection for early NSCLC with EGFR mutation, patients with advanced stage, pleural invasion, or limited resection are more likely to show postoperative relapse.

Background: s/Aims: Hepatocellular carcinoma (HCC) is the sixth most common cancer and second leading cause of cancer-related deaths in South Korea. This study evaluated the characteristics of Korean patients newly diagnosed with HCC in 2016-2018. Methods: Data from the Korean Primary Liver Cancer Registry (KPLCR), a representative database of patients newly diagnosed with HCC in South Korea, were analyzed. This study investigated 4,462 patients with HCC registered in the KPLCR in 2016-2018. Results: The median patient age was 63 years (interquartile range, 55-72). 79.7% of patients were male. Hepatitis B infection was the most common underlying liver disease (54.5%). The Barcelona Clinic Liver Cancer (BCLC) staging system classified patients as follows: stage 0 (14.9%), A (28.8%), B (7.5%), C (39.0%), and D (9.8%). The median overall survival was 3.72 years (95% confidence interval, 3.47-4.14), with 1-, 3-, and 5-year overall survival rates of 71.3%, 54.1%, and 44.3%, respectively. In 2016-2018, there was a significant shift toward BCLC stage 0-A and Child-Turcotte-Pugh liver function class A (P<0.05), although survival rates did not differ by diagnosis year. In the treatment group (n=4,389), the most common initial treatments were transarterial therapy (31.7%), surgical resection (24.9%), best supportive care (18.9%), and local ablation therapy (10.5%). Conclusions Between 2016 and 2018, HCC tended to be diagnosed at earlier stages, with better liver function in later years. However, since approximately half of the patients remained diagnosed at an advanced stage, more rigorous and optimized HCC screening strategies should be implemented.

Prime editing (PE) is a recently developed genome-editing technique that enables versatile editing. Despite its flexibility and potential, applying PE in human induced pluripotent stem cells (hiPSCs) has not been extensively addressed. Genetic disease models using patient-derived hiPSCs have been used to study mechanisms and drug efficacy. However, genetic differences between patient and control cells have been attributed to the inaccuracy of the disease model, highlighting the significance of isogenic hiPSC models. Hereditary hemorrhagic telangiectasia 1 (HHT1) is a genetic disorder caused by an autosomal dominant mutation in endoglin (ENG). Although previous HHT models using mice and HUVEC have been used, these models did not sufficiently elucidate the relationship between the genotype and disease phenotype in HHT, demanding more clinically relevant models that reflect human genetics. Therefore, in this study, we used PE to propose a method for establishing an isogenic hiPSC line. Clinically reported target mutation in ENG was selected, and a strategy for PE was designed. After cloning the engineered PE guide RNA, hiPSCs were nucleofected along with PEmax and hMLH1dn plasmids. As a result, hiPSC clones with the intended mutation were obtained, which showed no changes in pluripotency or genetic integrity. Furthermore, introducing the ENG mutation increased the expression of proangiogenic markers during endothelial organoid differentiation. Consequently, our results suggest the potential of PE as a toolkit for establishing isogenic lines, enabling disease modeling based on hiPSC-derived disease-related cells or organoids.This approach is expected to stimulate mechanistic and therapeutic studies on genetic diseases.

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.