Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients’ values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Purpose: Outcome analysis of urachal cancer (UraC) is limited due to the scarcity of cases and different staging methods compared to urothelial bladder cancer (UroBC). We attempted to assess survival outcomes of UraC and compare to UroBC after stage-matched analyses. Materials and Methods: Total 203 UraC patients from a multicenter database and 373 UroBC patients in single institution from 2000 to 2018 were enrolled (median follow-up, 32 months). Sheldon stage conversion to corresponding TNM staging for UraC was conducted for head-to-head comparison to UroBC. Perioperative clinical variables and pathological results were recorded. Stage-matched analyses for survival by stage were conducted. Results: UraC patients were younger (mean age, 54 vs. 67 years; p < 0.001), with 163 patients (80.3%) receiving partial cystectomy and 23 patients (11.3%) radical cystectomy. UraC was more likely to harbor ≥ pT3a tumors (78.8% vs. 41.8%). While 5-year recurrence-free survival, cancer-specific survival (CSS) and overall survival were comparable between two groups (63.4%, 67%, and 62.1% in UraC and 61.5%, 75.9%, and 67.8% in UroBC, respectively), generally favorable prognosis for UraC in lower stages (pT1-2) but unfavorable outcomes in higher stages (pT4) compared to UroBC was observed, although only 5-year CSS in ≥ pT4 showed statistical significance (p=0.028). Body mass index (hazard ratio [HR], 0.929), diabetes mellitus (HR, 1.921), pathologic T category (HR, 3.846), and lymphovascular invasion (HR, 1.993) were predictors of CSS for all patients. Conclusion Despite differing histology, UraC has comparable prognosis to UroBC with relatively favorable outcome in low stages but worse prognosis in higher stages. The presented system may be useful for future grading and risk stratification of UraC.

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the “proven GERD” with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett’s mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis. Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the “proven GERD” with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett’s mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis.Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the “proven GERD” with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett’s mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis.Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Background: This study was conducted to analyze clinical factors that can affect pregnancy rates in normal responders undergoing the freeze-all policy in in vitro fertilization. Methods: We evaluated 153 embryo transfer cycles in 89 infertile women with normal response to controlled ovarian stimulation (COS). After COS, all embryos were cultured to the blastocyst stage, and good quality blastocysts were vitrified for elective frozen-thawed embryo transfer (FET). Clinical variables associated with COS and the results of COS and culture, including the number of retrieved oocytes, fertilized oocytes, and frozen blastocysts were compared between the pregnant group and the non-pregnant group. Results: After a single cycle of COS for each patient, 52 patients became pregnant while 37 did not. Significant differences were observed in the number of matured oocytes, fertilized oocytes, frozen blastocysts, and transferred embryos. The number of frozen blastocysts in the pregnant group was almost twice that in the non-pregnant group (5.6±3.1 vs. 2.8±1.9, p<0.001). The area under the receiver operating characteristic curve for the 4 frozen blastocysts was 0.801 in the pregnant group. Conclusion In the freeze-all policy, the number of matured oocytes, number of fertilized oocytes, and number of frozen blastocysts might be predictive factors for pregnancy.

Secondary neoplasms in nevus sebaceous can develop during adolescence and adulthood. Trichoblastoma and syringocystadenoma papilliferum are the most common benign neoplasms, but poroma is rarely reported. A 28-year-old female presented with an asymptomatic mass on the scalp.She has had a hairless lesion on the scalp since birth. A soft mass developed on that lesion four years prior. Physical examination revealed a localized 1 cm×2.5 cm-sized brownish, verrucous-surfaced plaque with a 1 cm×1 cm-sized pedunculated erythematous tumor on the scalp. We performed skin biopsy on both the plaque and tumor lesions. The histopathological findings demonstrated the plaque lesion consistent with nevus sebaceous and the tumor lesion consistent with eccrine poroma. Surgical mass excision was performed.The patient was eventually diagnosed with eccrine poroma arising within nevus sebaceous. To the best of our knowledge, there are only six reported cases on poroma arising within nevus sebaceous. Although rarely documented in the literature, it should be considered as a secondary neoplasm within nevus sebaceous.