Background: s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy. Methods: CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns. Results: Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR). Conclusion The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.

Purpose: This study aimed to analyze whether the occurrence of complications increases if radiotherapy (RT) is administered after breast reconstructive surgery using implants. Methods: This retrospective study included 80 patients who underwent breast reconstruction using implants, of which 16 (20.0%) underwent RT. Most patients underwent conventional fractionated RT (n = 13), and hypofractionated RT was performed in 3 patients. Most patients (n = 51, 63.8%) underwent delayed reconstruction, which involved implant replacement after tissue expander insertion. Only 29 patients (36.3%) underwent immediate reconstruction simultaneously with breast cancer surgery. Results: The median postoperative follow-up was 39.9 months (range, 8.7–120.3 months). Complications occurred in 18 (22.5%); infectionecrosis (n = 8), leakage/rupture (n = 8), and capsular contracture (n = 2). Infectionecrosis is common in patients undergoing RT. Complications occurred in 4 patients (25.0%) who received RT and 14 (21.9%) who did not receive RT, and complications did not significantly increase with RT (P = 0.511). There was no overall difference in complications between the immediate (4 of 29) and delayed (14 of 51) reconstruction groups (P = 0.129). Nine patients underwent reoperation because of complications; 3 (18.8%) received RT and 6 (9.4%) did not receive RT. The reoperation rate did not increase significantly with RT (P = 0.254). There were 3 cases of recurrence, and patients who received RT had no recurrence. Conclusion RT did not significantly increase the complication or reoperation rates if reconstructive surgery was performed using implants. Therefore, RT should be performed in patients at a high risk of recurrence.

Purpose: This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer. Materials and Methods: A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery. Results: Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064). Conclusions Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.

Purpose: This study aimed to analyze whether the occurrence of complications increases if radiotherapy (RT) is administered after breast reconstructive surgery using implants. Methods: This retrospective study included 80 patients who underwent breast reconstruction using implants, of which 16 (20.0%) underwent RT. Most patients underwent conventional fractionated RT (n = 13), and hypofractionated RT was performed in 3 patients. Most patients (n = 51, 63.8%) underwent delayed reconstruction, which involved implant replacement after tissue expander insertion. Only 29 patients (36.3%) underwent immediate reconstruction simultaneously with breast cancer surgery. Results: The median postoperative follow-up was 39.9 months (range, 8.7–120.3 months). Complications occurred in 18 (22.5%); infectionecrosis (n = 8), leakage/rupture (n = 8), and capsular contracture (n = 2). Infectionecrosis is common in patients undergoing RT. Complications occurred in 4 patients (25.0%) who received RT and 14 (21.9%) who did not receive RT, and complications did not significantly increase with RT (P = 0.511). There was no overall difference in complications between the immediate (4 of 29) and delayed (14 of 51) reconstruction groups (P = 0.129). Nine patients underwent reoperation because of complications; 3 (18.8%) received RT and 6 (9.4%) did not receive RT. The reoperation rate did not increase significantly with RT (P = 0.254). There were 3 cases of recurrence, and patients who received RT had no recurrence. Conclusion RT did not significantly increase the complication or reoperation rates if reconstructive surgery was performed using implants. Therefore, RT should be performed in patients at a high risk of recurrence.

Purpose: This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer. Materials and Methods: A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery. Results: Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064). Conclusions Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.

Background: s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy. Methods: CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns. Results: Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR). Conclusion The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.

Purpose: This study aimed to analyze whether the occurrence of complications increases if radiotherapy (RT) is administered after breast reconstructive surgery using implants. Methods: This retrospective study included 80 patients who underwent breast reconstruction using implants, of which 16 (20.0%) underwent RT. Most patients underwent conventional fractionated RT (n = 13), and hypofractionated RT was performed in 3 patients. Most patients (n = 51, 63.8%) underwent delayed reconstruction, which involved implant replacement after tissue expander insertion. Only 29 patients (36.3%) underwent immediate reconstruction simultaneously with breast cancer surgery. Results: The median postoperative follow-up was 39.9 months (range, 8.7–120.3 months). Complications occurred in 18 (22.5%); infectionecrosis (n = 8), leakage/rupture (n = 8), and capsular contracture (n = 2). Infectionecrosis is common in patients undergoing RT. Complications occurred in 4 patients (25.0%) who received RT and 14 (21.9%) who did not receive RT, and complications did not significantly increase with RT (P = 0.511). There was no overall difference in complications between the immediate (4 of 29) and delayed (14 of 51) reconstruction groups (P = 0.129). Nine patients underwent reoperation because of complications; 3 (18.8%) received RT and 6 (9.4%) did not receive RT. The reoperation rate did not increase significantly with RT (P = 0.254). There were 3 cases of recurrence, and patients who received RT had no recurrence. Conclusion RT did not significantly increase the complication or reoperation rates if reconstructive surgery was performed using implants. Therefore, RT should be performed in patients at a high risk of recurrence.

Purpose: This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer. Materials and Methods: A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery. Results: Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064). Conclusions Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.

Background: s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy. Methods: CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns. Results: Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR). Conclusion The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.

Background: Ensuring reference material (RM) commutability is crucial for evaluating measurement traceability in order to standardize laboratory tests. However, commutability assessment is not routinely performed. We assessed whether RMs prepared following CLSI C37-A guidelines could be used without assessing commutability by evaluating their commutability for four lipid measurements using the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and CLSI EP14 protocols. Methods: We analyzed total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in frozen sera from 20 individuals and 11 RMs, prepared by the Korea Disease Control and Prevention AgencyLaboratory Standardization Project (per CLSI C37-A), using six routine measurement procedures (MPs). Regression equations and 95% prediction intervals derived from single-donor sera were analyzed following CLSI EP14. The IFCC protocol was used to assess differences in inter-MP biases between RM and clinical samples. The effect of the TG concentration on commutability was evaluated by analyzing biases between MP results and reference procedure-assigned values. Results: RMs were commutable for most MP pairs for TC and TG. Commutability for HDL-C and LDL-C varied across RMs, with RM10 and RM11 showing higher TG levels (2.38 and 2.95 mmol/L, respectively) and lower commutability. Increased bias percentages from assigned values were observed for RMs with higher TG levels. Conclusions RMs prepared per CLSI C37-A were commutable with most MP pairs for TC and TG. Elevated TG levels affected HDL-C and LDL-C commutability, highlighting the need to consider TG concentrations during RM preparation and assess commutability to standardize laboratory tests.