Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment.

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.

Comparison of robotic and laparoscopic lateral transperitoneal adrenalectomies.

Purpose: This study aimed to compare the intraoperative and postoperative outcomes between robotic and laparoscopic transperitoneal adrenalectomies. Methods: In this retrospective study, 93 patients underwent adrenalectomy using 2 surgical modalities: 45 patients underwent adrenalectomy using the da Vinci Xi system (robotic group), and 48 patients using laparoscopic devices (laparoscopic group). We compared the operation time, intraoperative bleeding, and hospital stay according to the surgical modality and tumor characteristics. Results: There were no significant differences in the operative time (P = 0.827), hospital stay (P = 0.177), and intraoperative bleeding (P = 0.174) between the groups. However, the robotic group showed a lower coefficient of variation in total operative time than that of the laparoscopic group (100.6 ± 23.3 minutes vs. 101.9±32.7 minutes, 0.230 vs. 0.321). When divided into 2 subgroups based on the tumor size (<3 cm and ≥3 cm), the robotic group with a tumor sized >3 cm had a shorter operative time than that of the laparoscopic group (P = 0.032). The robotic group also had fewer cases of intraoperative bleeding (P = 0.034). Conclusions: Compared to the laparoscopic transperitoneal adrenalectomy, the robotic one achieved a lower deviation in total operative time and showed less bleeding and a shorter operative time, especially for tumors sized >3 cm.

2022 Seoul Consensus on Clinical Practice Guidelines for Functional Constipation.

Chronic constipation is one of the most common digestive diseases encountered in clinical practice. Constipation manifests as a variety of symptoms, such as infrequent bowel movements, hard stools, feeling of incomplete evacuation, straining at defecation, a sense of anorectal blockage during defecation, and use of digital maneuvers to assist defecation. During the diagnosis of chronic constipation, the Bristol Stool Form Scale, colonoscopy, and a digital rectal examination are useful for objective symptom evaluation and differential diagnosis of secondary constipation. Physiological tests for functional constipation have complementary roles and are recommended for patients who have failed to respond to treatment with available laxatives and those who are strongly suspected of having a defecatory disorder. As new evidence on the diagnosis and management of functional constipation emerged, the need to revise the previous guideline was suggested. Therefore, these evidence-based guidelines have proposed recommendations developed using a systematic review and meta-analysis of the treatment options available for functional constipation. The benefits and cautions of new pharmacological agents (such as lubiprostone and linaclotide) and conventional laxatives have been described through a meta-analysis. The guidelines consist of 34 recommendations, including 3 concerning the definition and epidemiology of functional constipation, 9 regarding diagnoses, and 22 regarding managements. Clinicians (including primary physicians, general health professionals, medical students, residents, and other healthcare professionals) and patients can refer to these guidelines to make informed decisions regarding the management of functional constipation.

Long-term incidence of depression in rectal cancer patients with or without stoma: a population-based cohort study.

Purpose: Significant improvements have been made in the surgical treatment of rectal cancer with a higher sphincter-saving rate without compromising oncologic results. There have been studies about the quality of life of rectal cancer patients after surgery. However, no study has reported the long-term annual incidence of depression after rectal cancer surgery according to stoma status. The objective of this study was to determine the annual incidence of depression after rectal cancer surgery and the factors affecting it, especially the prevalence of depression according to the presence or duration of a stoma. Methods: Using the Korea National Health Insurance Service database, patients who underwent radical surgery for rectal cancer from 2002 to 2019 were searched. We analyzed the incidence and risk factors of depression in patients who underwent radical surgery for rectal cancer according to stoma status. Results: Annual incidence of depression in rectal cancer patients was decreasing annually for 15 years after surgery. There was no statistically significant difference in the incidence of depression according to the stoma status. However, the diagnosis of depression within 1 year after surgery was statistically significantly increased in the permanent stoma group. Conclusion: There was no difference in the overall incidence of depressive disorders among patients with rectal cancer based on their stoma status. However, a permanent stoma seems to increase the incidence in the first year after surgery. Education and intensive assessments of depressive disorders in patients with permanent stoma within 1 year after surgery are needed, particularly for female patients who are under 50 years old.

Long-term oncologic outcome of D3 lymph node dissection for clinical stage 2/3 right-sided colon cancer.

PURPOSE: To investigate oncologic outcomes including overall survival and disease-free survival depending on the extent of lymphadenectomy (D3 versus D2) by comparing D3 and D2 lymphadenectomy in patients with clinical stage 2/3 right colon cancer. METHODS: Consecutive series of patients who underwent radical resection for right colon cancer at our three hospitals between January 2015 and June 2018 were retrospectively analyzed. Study cohorts were divided into two groups: D3 group and D2 group. Oncologic, pathologic, and perioperative outcomes of the two groups were compared. RESULTS: A total of 295 patients (167 in the D2 group and 128 in the D3 group) were included in this study. Patients' characteristics showed no significant difference between the two groups. The median number of harvested lymph nodes was significantly higher in the D3 group than in the D2 group. The rate of complications was not significantly different between the two groups except for chyle leakage, which was more frequent in the D3 group. Five-year disease-free survival was 90.2% (95% CI: 84.8-95.9%) in the D3 group, which was significantly (p = 0.028) higher than that (80.5%, 95% CI: 74-87.5%) in the D2 group. There was no significant difference in overall survival between the two groups. CONCLUSION: Our results indicate that D3 lymphadenectomy is associated with more favorable 5-year disease-free survival than D2 lymphadenectomy for patients with stage 2/3 right-sided colon cancer. D3 lymphadenectomy might improve oncologic outcomes in consideration of the recurrence rate.

Impact of D3 lymph node dissection on upstaging and short-term survival in clinical stage I right-sided colon cancer.

BACKGROUND: D3 lymph node dissection is becoming the standard procedure for the treatment of advanced right colon cancer and has shown increasing evidence of its oncologic benefit. However, a clear indication for its application is lacking and data on this topic is unsatisfactory. Thus, the necessity for D3 lymph node dissection in clinical stage I right colon cancer remains controversial. METHODS: We retrospectively analyzed data from clinical stage I right colon cancer patients who underwent radical surgery at three hospitals of Korea university medical center between January 2015 and June 2018. We compared surgical complications and short-term oncologic outcomes between D2 and D3 lymph node dissections in these patients. RESULTS: Among 512 patients, 122 (23.8%) were clinical stage I. Of these, 88 and 34 patients received D2 and D3 lymph node dissection, respectively. There were no statistically significant differences in clinicopathologic variables and surgical outcomes between the two groups. Upstaging occurred in 16 patients (47.1%) in the D3 group and 23 patients (26.1%) in the D2 group. There were four recurrences in the D2 group but no recurrence in the D3 group. Log-rank tests showed no statistically significant difference in disease-free survival rates between the two groups (p = 0.210). CONCLUSION: There was no significant difference in disease-free survival rates between D2 and D3 lymph node dissection in clinical stage I right colon cancer patients. However, recurrence occurred in the D2 group. Efforts to improve the accuracy of clinical staging are required and more studies with better quality are needed.

Detailed comparison of robotic and endoscopic transaxillary thyroidectomy.

BACKGROUND: Robotic thyroidectomy is increasingly used for patients with papillary thyroid carcinoma (PTC). We compared the differences between robotic and endoscopic transaxillary thyroidectomy with regard to surgical procedures. METHODS: This retrospective study enrolled 40 patients with PTC who underwent robotic hemithyroidectomy (robot group) using the Da Vinci S system and 37 patients (endoscopic group) who underwent endoscopic hemithyroidectomy. Video files of surgery for all patients were analyzed to compare the operation procedures: (flap creation, docking [only for robot group], dissection of the superior pole, dissection of the inferior pole, identification of parathyroid glands [PTGs] and the recurrent laryngeal nerve [RLN], dissection of the thyroid along the trachea, bleeding control, application of a drain, and wound closure). The duration of each procedure and the clinicopathological characteristics were analyzed. RESULTS: Procedure time for patients in the robot group was shorter for inferior pole dissection and for identification of the PTGs and RLN (37.5 min vs. 50.5 min, p = 0.008). Mean total operative times for the two groups were comparable (153.0 min vs. 150.2 min, p = 0.732); however, excluding the docking procedure, operation time was shorter for the robot group (133.3 min vs. 150.2 min, p = 0.038). The number of sacrificed PTGs was also significantly smaller in the robot group (0.35 ± 0.53 vs. 0.65 ± 0.68, p = 0.036). CONCLUSION: Compared to endoscopic thyroidectomy, robotic transaxillary thyroidectomy involved a shorter time for inferior pole dissection and PTGs and RLN identification; moreover, more PTGs were spared using this procedure.

Effects of splanchnic vasoconstrictors on liver regeneration and survival after 90% rat hepatectomy.

PURPOSE: Posthepatectomy liver failure is a serious complication and considered to be caused by increased portal pressure and flow. Splanchnic vasoactive agents and propranolol are known to decrease portal pressure. The aim of this study was to identify optimal candidates with potential for clinical use among somatostatin, terlipressin, and propranolol using rats with 90% hepatectomy. METHODS: Rats were divided into 5 groups: sham operation (n = 6), control (n = 20), propranolol (n = 20), somatostatin (n = 20), and terlipressin group (n = 20). Seven-day survival rates and portal pressure change were measured, and biochemical, histologic, and molecular analyses were performed. RESULTS: Portal pressure was significantly decreased in all 3 treatment groups compared to control. All treatment groups showed a tendency of decreased liver injury markers, and somatostatin showed the most prominent effect at 24 hours postoperatively. Histologic liver injury at 24 hours was significantly decreased in propranolol and terlipressin groups (P = 0.016, respectively) and somatostatin group showed borderline significance (P = 0.056). Hepatocyte proliferation was significantly increased after 24 hours in all treatment groups. Median survival was significantly increased in terlipressin group compared to control group (P < 0.01). CONCLUSION: Terlipressin is considered as the best candidate, while somatostatin has good potential for clinical use, considering their effects on portal pressure and subsequent decrease in liver injury and increase in liver regeneration.

Effect of a Shortened Duration of FOLFOX Chemotherapy on the Survival Rate of Patients with Stage II and III Colon Cancer.

BACKGROUND: FOLFOX chemotherapy is widely used as an adjuvant treatment for advanced colon cancer. The duration of adjuvant chemotherapy is usually set to 6 months, which is based on a former study of 5-fluorouracil/leucovorin chemotherapy. However, the FOLFOX regimen is known to have complications, such as peripheral neuropathy. The aim of this study was to compare the survival rates and complications experienced by patients receiving either 4 or 6 months of FOLFOX chemotherapy. METHODS: Retrospective data analysis was performed for stage II and III patients who underwent radical resection of colon cancer. We compared the 5-year survival rates and the occurrence of complications in patients who completed only 8 cycles of FOLFOX chemotherapy with patients who completed 12 cycles of chemotherapy. RESULTS: Among 188 patients who underwent adjuvant FOLFOX chemotherapy for stage II or III colon cancer, 83 (44.1%) completed 6 months of FOLFOX chemotherapy and 64 (34.0%) patients discontinued after 4 months of chemotherapy. The 5-year overall survival and disease-free survival rates did not show a significant difference. Patients in the 6-month group had peripheral neuropathy more frequently (p = 0.028). CONCLUSIONS: Five-year overall and disease-free survival were not significantly different between the 2 groups. Large-scale prospective studies are necessary for the analysis of complications and survival rates.

Clinical Significance of 5-Fluorouracil Chemosensitivity Testing in Patients with Colorectal Cancer.

AIM: To evaluate whether the results of chemosensitivity testing were associated with prognosis of colorectal cancer patients after adjuvant 5-fluorouracil (FU)/ leucovorin chemotherapy. PATIENTS AND METHODS: Eighty-nine patients who received 5-FU/leucovorin adjuvant chemotherapy for colorectal cancer were enrolled. Chemosensitivity tests were performed and tumor growth inhibition rate was calculated using the MTT (3-(4,5-dimethylthiazol-2-yl)02,5-diphenyl-2H tetrazolium bromide) assay. RESULTS: Fifty-one patients (57.3%) were sensitive to 5-FU according to the chemosensitivity test. After a median follow-up of 64 months, there was a significant difference between the 5-year disease-free survival rates of the chemo-sensitive and chemo-resistant groups. However, there was no significant difference in the overall 5-year survival between the chemo-sensitive and chemo-resistant groups. CONCLUSION: A positive 5-FU sensitivity test with in vitro histoculture drug response assay (HDRA) was associated with better disease-free survival. Chemosensitivity may be a prognostic factor for colorectal cancer patients undergoing adjuvant 5-FU/leucovorin chemotherapy.

Lymph Node Micrometastasis Cannot Be Considered as Positive Lymph Node in Nonmetastatic Colorectal Cancer.

The prognostic value of micrometastasis in colorectal cancer (CRC) remains controversial. The study investigated whether lymph node (LN) micrometastasis can have prognostic value in CRC as compared with macrometastasis. The study included 488 patients with curatively resected stage I, II, or III CRC treated between 2004 and 2011. Immuohistochemical staining with monoclonal antibody CAM 5.2 was performed on negative LNs by hematoxylin-eosin staining. The prognostic value of LN micrometastasis was investigated in multivariate analysis. Regression analysis was performed to identify a causal relationship between micro- and macrometastasis. Survival differences were compared between conventional N staging and hypothetic N staging taking micrometastasis in the positive node. A total of 93 patients (19.1%) showed LN micrometastasis. Patients with micrometastasis had more advanced tumor characteristics in terms of tumor size, grade, T stage, N stage, lymphatic invasion, and vascular invasion. In multivariate analysis, micrometastasis was not related with recurrence. Preoperative carcinoembryonic antigen level, neural invasion, and macrometastasis were independent risk factors in the analysis. Regression analysis showed that there was not a causal relationship between micro- and macrometastasis (R2 = 0.004, P = 0.153). When the cumulative numbers of micro- and macrometastatic LNs were calculated together, the discriminative power of survival difference between each node stage became less prominent, compared with conventional N staging. LN micrometastasis is related with advanced tumor characteristics, but does not reflect poor prognosis in nonmetastatic CRC. Micrometastasis cannot be considered as positive LN to predict poor prognosis.

Clinical benefits and oncologic equivalence of self-expandable metallic stent insertion for right-sided malignant colonic obstruction.

BACKGROUND: The efficacy of stenting for right-sided malignant colonic obstruction is unknown. This study aimed to evaluate the safety, feasibility, and clinical benefits of self-expandable metallic stent insertion for right-sided malignant colonic obstruction. METHODS: Clinical data from patients who underwent right hemicolectomy for right colon cancer from January 2006 to July 2014 at three Korea University hospitals were retrospectively reviewed. A total of 39 patients who developed malignant obstruction in the right-sided colon were identified, and their data were analyzed. RESULTS: Stent insertion was attempted in 16 patients, and initial technical success was achieved in 14 patients (87.5 %). No stent-related immediate complications were reported. Complete relief from obstruction was achieved in all 14 patients. Twenty-five patients, including two patients who failed stenting, underwent emergency surgery. In the stent group, 93 % (13/14) of patients underwent elective laparoscopic surgery, and only one surgery was converted to an open procedure. All patients in the emergency group underwent emergency surgery within 24 h of admission. In the emergency group, only 12 % (3/25) of patients underwent laparoscopic surgery, with one surgery converted to an open procedure. All patients in both groups underwent either laparoscopy-assisted or open right/extended right hemicolectomy with primary anastomoses as the first operation. The operative times, retrieved lymph nodes, and pathologic stage did not differ between the two groups. Postoperative hospital stay (9.4 ± 3.4 days in the stent group vs. 12.4 ± 5.9 in the emergency group, p = 0.089) and time to resume oral food intake (3.2 ± 2.1 days in the stent group vs. 5.7 ± 3.4 in the emergency group, p = 0.019) were shorter in the stent group. And there were no significant differences in disease-free survival and overall survival between the two groups. CONCLUSIONS: Stent insertion appears to be safe and feasible in patients with right-sided colonic malignant obstruction. It facilitates minimally invasive surgery and may result in better short-term surgical outcomes.

Mechanical Bowel Preparation Does Not Affect Clinical Severity of Anastomotic Leakage in Rectal Cancer Surgery.

BACKGROUND: Previous multicenter randomized trials demonstrated that omitting mechanical bowel preparation (MBP) did not increase anastomotic leakage rates or other infectious complications. However, the most serious concern regarding the omission of MBP is ongoing fecal peritonitis after anastomotic leakage occurs. The aim of this study was to compare the clinical manifestations and severity of anastomotic leakage between patients who underwent MBP and those who did not. METHODS: This study was a single-center retrospective review of a prospectively maintained database. From January 2006 to September 2013, 1369 patients who underwent elective rectal cancer resection with primary anastomosis were identified and analyzed. RESULTS: Anastomotic leakage rates were not significantly different between patients who did not undergo MBP (77/831, 9.27%) and those who did (42/538, 7.81%). However, a significantly lower rate of clinical leakage requiring surgical exploration was observed in the leakage without MBP group (30/77, 39.0%) compared with the leakage with MBP group (30/42, 71.4%) (P = 0.001). There were no significant differences in the clinical severity of anastomotic leakage as assessed by the length of hospital stay, time to resuming a normal diet, length of antibiotic use, ileus rate, transfusion rate, ICU admission rate, and mortality rate between the leakage without MBP and leakage with MBP groups. CONCLUSION: MBP was not found to affect the clinical severity of anastomotic leakage in elective rectal cancer surgery.

Risk factors causing structural sequelae after anastomotic leakage in mid to low rectal cancer.

AIM: To investigate the risk factors causing structural sequelae after anastomotic leakage in patients with mid to low rectal cancer. METHODS: Prospectively collected data of consecutive subjects who had anastomotic leakage after surgical resection for rectal cancer from March 2006 to May 2013 at Korea University Anam Hospital were retrospectively analyzed. Two subgroup analyses were performed. The patients were initially divided into the sequelae (stricture, fistula, or sinus) and no sequelae groups and then divided into the permanent stoma (PS) and no PS groups. Univariate and multivariate analyses were performed to identify the risk factors of structural sequelae after anastomotic leakage. RESULTS: Structural sequelae after anastomotic leakage were identified in 29 patients (39.7%). Multivariate analysis revealed that diversion ileostomy at the first operation increases the risk of structural sequelae [odds ratio (OR) = 6.741; P = 0.017]. Fourteen patients (17.7%) had permanent stoma during the follow-up period (median, 37 mo). Multivariate analysis showed that the tumor level from the dentate line was associated with the risk of permanent stoma (OR = 0.751; P = 0.045). CONCLUSION: Diversion ileostomy at the first operation increased the risk of structural sequelae of the anastomosis, while lower tumor location was associated with the risk of permanent stoma in the management of anastomotic leakage.

Endoscopic obstruction in rectal cancers: survival and recurrence patterns following curative surgery.

BACKGROUND: It is controversial whether preoperative obstruction in rectal cancers can affect prognosis or influence recurrence patterns. We investigated the association between endoscopic obstruction with survival and recurrence patterns in patients with locally advanced rectal cancers. MATERIALS AND METHODS: An observational study and multivariate analysis were conducted to identify determinants of survival and to compare recurrence patterns between patients with obstructive or nonobstructive tumors after curative resection. Endoscopic obstruction was defined as a luminal obstruction of the rectum severe enough to prevent the colonoscope from passing beyond the tumor. RESULTS: Cancer was obstructive in 91 patients (16.8%) and nonobstructive in 452 (83.2%). Median follow-up was 50 (range, 3-161) months. Local recurrence occurred in 17 patients (14 nonobstructed [5.4%] and 3obstructed [5.5%]; P=1.0) and systemic recurrence in 83 (62 nonobstructed [23.8%] and 21 obstructed [38.2%]; P=.042]). Endoscopic obstruction was a significant prognostic factor in stage III rectal cancers (P=.001) but not in stage II tumors. The multivariate analysis showed that endoscopic obstruction was an independent prognostic factor for overall survival, but not for disease-free survival, in patients with stage III rectal cancers. Endoscopic obstruction was associated with multiple-site systemic recurrence that was unsalvageable (salvageable surgery, 24 nonobstructed [40%] and 2 obstructed [10%]; P=.014). CONCLUSIONS: Endoscopic obstruction in patients with stage III rectal cancer predicted worse overall survival and was associated with multiple-site systemic recurrence.

Analysis of the occupational stress of Korean surgeons: a pilot study.

PURPOSE: Surgeons serve one of the most challenging and stressful professions. Ineffective control of occupational stress leads to burnout of the surgeon. The aim of this study was to obtain preliminary data on the sources and the degree of stress of surgeons and to determine the feasibility of the survey. METHODS: A total of 63 surgeons in our three affiliated hospitals were enrolled in this study. Fifty-five questions were used to assess the demographics, characteristics and Korean occupational stress scale (KOSS), which were prepared and validated by the National Study for Development and Standardization of Occupational Stress. RESULTS: Forty-seven of the 63 surgeons participated in this study (74.6%). The mean KOSS score of the survey was 50.9 ± 8.55, which was significantly higher than that of other professions (P < 0.01). Drinking and smoking habits were not related to the KOSS score. Doing exercise was related to a low KOSS score in terms of low KOSS total score (P < 0.01). Average duty hours (P < 0.01) and night duty days per week (P = 0.01) were strongly related to higher KOSS in the linear regression analysis. CONCLUSION: This is the first study to evaluate job stress of surgeons in Korea. This study showed that Korean Surgeons had higher occupational stress than other Korean professions. A larger study based on this pilot study will help generate objective data for occupational stress of Korean Surgeons by performing a survey of the members of the Korean Surgical Society.

Laparoscopic hernia sac transection and intracorporeal ligation show very low recurrence rate in pediatric inguinal hernia.

BACKGROUND: There are many variable techniques for laparoscopic inguinal hernia repair in children. The aim of this study was to examine the feasibility of the laparoscopic hernia technique, which is based on the same surgical principles as conventional open herniotomy. SUBJECTS AND METHODS: Between November 2008 and August 2011, 207 pediatric patients with inguinal hernia were included in this study under informed consent. All of the patients underwent the laparoscopic technique of sac transection and intracorporeal ligation. An asymptomatic contralateral patent processus vaginalis (cPPV) was repaired using the same method. Patients were routinely followed for 2 years. Perioperative complications and recurrence rate were evaluated. RESULTS: In total, 202 patients were enrolled in the final analysis. The mean follow-up period was 12.5 months. The percentage of patients with cPPV was 39.2%. The mean operation time was 26 minutes for unilateral hernias and 34 minutes for bilateral hernias. One patient had a mild hematoma in the inguinal area in the immediate postoperative period, but it resolved spontaneously within 7 days. Recurrence and metachronous hernias have not been observed thus far. CONCLUSIONS: Laparoscopic hernia sac transection and intracorporeal ligation can be a safe and effective alternative for conventional herniotomy.