Purpose: Right-sided tumors have been reported to have a poorer survival rate than left-sided tumors; however, there remains debate regarding whether sidedness is an independent prognostic factor in colorectal cancer liver metastasis (CRLM). This study aimed to assess the impact of sidedness on prognosis in resectable CRLM and to identify prognostic factors. Methods: Patients who underwent liver resection for CRLM at Samsung Medical Center from January 2008 to December 2021 were included in the investigation. Overall survival (OS) and progression-free survival (PFS) were analyzed, and prognostic factors were identified. Results: A total of 497 patients were included in the study, with 106 on the right side and 391 on the left side. The rightsided group had a higher percentage of synchronous tumors (90.6% vs. 80.3%, P = 0.020). In survival analysis, the right side showed lower 5-year OS (49.7% vs. 54.2, P = 0.305) and 5-year PFS (57.1% vs. 60.2%, P = 0.271), but the differences were not statistically significant. In the analysis of prognostic factors, synchronous tumor (odds ratio [OR], 5.01; P < 0.001), CEA (OR, 1.46; P = 0.016), and maximum tumor size of hepatic metastasis (OR, 1.09; P = 0.026) were associated with OS. Conclusion In resectable CRLM, there was no difference in prognosis based on sidedness. CEA level, synchronous tumor, and maximum tumor size of hepatic metastasis were identified as prognostic factors.

Purpose: Right-sided tumors have been reported to have a poorer survival rate than left-sided tumors; however, there remains debate regarding whether sidedness is an independent prognostic factor in colorectal cancer liver metastasis (CRLM). This study aimed to assess the impact of sidedness on prognosis in resectable CRLM and to identify prognostic factors. Methods: Patients who underwent liver resection for CRLM at Samsung Medical Center from January 2008 to December 2021 were included in the investigation. Overall survival (OS) and progression-free survival (PFS) were analyzed, and prognostic factors were identified. Results: A total of 497 patients were included in the study, with 106 on the right side and 391 on the left side. The rightsided group had a higher percentage of synchronous tumors (90.6% vs. 80.3%, P = 0.020). In survival analysis, the right side showed lower 5-year OS (49.7% vs. 54.2, P = 0.305) and 5-year PFS (57.1% vs. 60.2%, P = 0.271), but the differences were not statistically significant. In the analysis of prognostic factors, synchronous tumor (odds ratio [OR], 5.01; P < 0.001), CEA (OR, 1.46; P = 0.016), and maximum tumor size of hepatic metastasis (OR, 1.09; P = 0.026) were associated with OS. Conclusion In resectable CRLM, there was no difference in prognosis based on sidedness. CEA level, synchronous tumor, and maximum tumor size of hepatic metastasis were identified as prognostic factors.

Purpose: Right-sided tumors have been reported to have a poorer survival rate than left-sided tumors; however, there remains debate regarding whether sidedness is an independent prognostic factor in colorectal cancer liver metastasis (CRLM). This study aimed to assess the impact of sidedness on prognosis in resectable CRLM and to identify prognostic factors. Methods: Patients who underwent liver resection for CRLM at Samsung Medical Center from January 2008 to December 2021 were included in the investigation. Overall survival (OS) and progression-free survival (PFS) were analyzed, and prognostic factors were identified. Results: A total of 497 patients were included in the study, with 106 on the right side and 391 on the left side. The rightsided group had a higher percentage of synchronous tumors (90.6% vs. 80.3%, P = 0.020). In survival analysis, the right side showed lower 5-year OS (49.7% vs. 54.2, P = 0.305) and 5-year PFS (57.1% vs. 60.2%, P = 0.271), but the differences were not statistically significant. In the analysis of prognostic factors, synchronous tumor (odds ratio [OR], 5.01; P < 0.001), CEA (OR, 1.46; P = 0.016), and maximum tumor size of hepatic metastasis (OR, 1.09; P = 0.026) were associated with OS. Conclusion In resectable CRLM, there was no difference in prognosis based on sidedness. CEA level, synchronous tumor, and maximum tumor size of hepatic metastasis were identified as prognostic factors.

Gout is the most common form of arthritis, with the prevalence increasing worldwide. The present treatment guidelines provide recommendations for the appropriate treatment of acute gout, management during the inter-critical period, and prevention of chronic complications. The guidelines were developed based on evidence-based medicine and draft recommendations finalized after expert consensus. These guidelines are designed to provide clinicians with clinical evidence to enable efficient treatment of gout.

Gout is the most common form of arthritis, with the prevalence increasing worldwide. The present treatment guidelines provide recommendations for the appropriate treatment of acute gout, management during the inter-critical period, and prevention of chronic complications. The guidelines were developed based on evidence-based medicine and draft recommendations finalized after expert consensus. These guidelines are designed to provide clinicians with clinical evidence to enable efficient treatment of gout.

Purpose: BRCA1 and BRCA2 are among the most important genes involved in DNA repair via homologous recombination (HR). Germline BRCA1/2 (gBRCA1/2)-related cancers have specific characteristics and treatment options but conducting gBRCA1/2 testing and interpreting the genetic imprint are sometimes complicated. Here, we describe the concordance of gBRCA1/2 derived from a panel of clinical tumor tissues using next-generation sequencing (NGS) and genetic aspects of tumors harboring gBRCA1/2 pathogenic variants. Materials and Methods: Targeted sequencing was performed using available tumor tissue from patients who underwent gBRCA1/2 testing. Comparative genomic analysis was performed according to gBRCA1/2 pathogenicity. Results: A total of 321 patients who underwent gBRCA1/2 testing were screened, and 26 patients with gBRCA1/2 pathogenic (gBRCA1/2p) variants, eight patients with gBRCA1/2 variants of uncertain significance (VUS; gBRCA1/2v), and 43 patients with gBRCA1/2 wild-type (gBRCA1/2w) were included in analysis. Mutations in TP53 (49.4%) and PIK3CA (23.4%) were frequently detected in all samples. The number of single-nucleotide variants (SNVs) per tumor tissue was higher in the gBRCA1/2w group than that in the gBRCA1/2p group (14.81 vs. 18.86, p=0.278). Tumor mutation burden (TMB) was significantly higher in the gBRCA1/2w group than in the gBRCA1/2p group (10.21 vs. 13.47, p=0.017). Except for BRCA1/2, other HR-related genes were frequently mutated in patients with gBRCA1/2w. Conclusion We demonstrated high sensitivity of gBRCA1/2 in tumors analyzed by NGS using a panel of tumor tissues. TMB value and aberration of non-BRCA1/2 HR-related genes differed significantly according to gBRCA1/2 pathogenicity in patients with breast cancer.

Purpose: The survival benefit of neoadjuvant chemotherapy (NAC) prior to surgical resection in colorectal cancer with liver metastases (CRCLM) patients remains controversial. The aim of this study was to compare overall outcome of CRCLM patients who underwent NAC followed by surgical resection versus surgical treatment first. Methods: We retrospectively analyzed 429 patients with stage IV colorectal cancer with synchronous liver metastases who underwent simultaneous liver resection between January 2008 and December 2016. Using propensity score matching, overall outcome between 60 patients who underwent NAC before surgical treatment and 60 patients who underwent surgical treatment first was compared. Results: Before propensity score matching, metastatic cancer tended to involve a larger number of liver segments and the primary tumor size was bigger in the NAC group than in the primary resection group, so that a larger percentage of patients in the NAC group underwent major hepatectomy (P<0.001). After propensity score matching, demographic features and pathologic outcomes showed no significant differences between the 2 groups. In addition, there was no significant difference in short-term recovery outcomes such as postoperative morbidity (P=0.603) and oncologic outcome, including 3-year overall survival rate (P=0.285) and disease-free survival rate (P=0.730), between the 2 groups. Conclusion NAC prior to surgical treatment in CRCLM is considered a safe treatment that does not increase postoperative morbidity, and its impact on oncologic outcome was not inferior.

Purpose: The association of serum lipids with gastric cancer is controversial. We clarified the role of serum lipids in the development, progression, and prognosis of gastric cancer. Materials and Methods: In total, 412 patients diagnosed with gastric cancer were prospectively recruited, and 2,934 control subjects who underwent screening endoscopy were enrolled from December 2013 to March 2017 to conduct a case-control study in a tertiary center. Serum lipid profiles, including total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), apolipoprotein A-I (apoA-I), and apolipoprotein B, and clinicopathologic characteristics were analyzed. Results: The gastric cancer group showed significantly lower HDL-C, higher LDL-C, and lower apoA-I level than the control group. In multivariate analysis, old age (odds ratio [OR], 1.051; p < 0.001), smoking (OR, 1.337; p < 0.001), a family history of gastric cancer (OR, 2.038; p < 0.001), Helicobacter pylori seropositivity (OR, 4.240; p < 0.001), lower HDL-C (OR, 0.712; p=0.020), and higher LDL-C (p=0.002) were significant risk factors for gastric cancer. Lower HDL-C and higher LDL-C remained significant after adjustments for covariates, including age and sex. In a subgroup analysis of the gastric cancer group, lower TG levels were associated with undifferentiated histology. No serum lipids were associated with overall survival. Conclusion Lower HDL-C and higher LDL-C were associated with the risk of gastric cancer, even after adjusting for age, sex, and other factors. In the gastric cancer group, undifferentiated histology was associated with lower TG levels.

Background/Aims: The learning curve is essential in endoscopic submucosal dissection (ESD) training to improve outcomes and reduce the risk of procedure-related complications. We compared the outcomes of gastric ESD in live pigs performed by inexperienced endoscopists with or without ex vivo training. Materials and Methods: At the Olympus Medical Training and Education Center, nine endoscopists inexperienced in ESD were randomly divided into two groups (group A: ex vivo training followed by in vivo training; group B: in vivo training only), and they performed gastric ESDs. Results: A total of 18 ESDs were performed. The en bloc resection rate was 88.9% (16/18), and the complete resection rate was 94.4% (17/18). The median specimen size was 2.5 cm in group A and 2.1 cm in group B (P=0.227). There was no significant difference in the procedure time between the two groups, except for the marking time (0′58″ vs. 2′58″, P=0.027). However, group A took a shorter time in dissecting the same area than group B (109 vs. 246 sec/cm2, P=0.083). Complication rates were not significantly different between both groups. Conclusions The procedure time during in vivo ESD training in pigs may be shortened by prior ex vivo training. However, the ex vivo model presented poor air inflation, unstable fixation, and excessive mucosal hardness for cutting. An advanced simulator or sufficient ex vivo training may be effective in training for the ESD procedure.

Purpose: The survival benefit of neoadjuvant chemotherapy (NAC) prior to surgical resection in colorectal cancer with liver metastases (CRCLM) patients remains controversial. The aim of this study was to compare overall outcome of CRCLM patients who underwent NAC followed by surgical resection versus surgical treatment first. Methods: We retrospectively analyzed 429 patients with stage IV colorectal cancer with synchronous liver metastases who underwent simultaneous liver resection between January 2008 and December 2016. Using propensity score matching, overall outcome between 60 patients who underwent NAC before surgical treatment and 60 patients who underwent surgical treatment first was compared. Results: Before propensity score matching, metastatic cancer tended to involve a larger number of liver segments and the primary tumor size was bigger in the NAC group than in the primary resection group, so that a larger percentage of patients in the NAC group underwent major hepatectomy (P<0.001). After propensity score matching, demographic features and pathologic outcomes showed no significant differences between the 2 groups. In addition, there was no significant difference in short-term recovery outcomes such as postoperative morbidity (P=0.603) and oncologic outcome, including 3-year overall survival rate (P=0.285) and disease-free survival rate (P=0.730), between the 2 groups. Conclusion NAC prior to surgical treatment in CRCLM is considered a safe treatment that does not increase postoperative morbidity, and its impact on oncologic outcome was not inferior.