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.

Stereotactic Navigation-Assisted Laparoscopic Resection of Challenging Low Pelvic Tumors: A Case Series.

(1) Introduction: The laparoscopic approach to low pelvic tumors is challenging and hindered by suboptimal tumor visualization and dissection, with possible oncological failure. Stereotactic navigation provides real-time image guidance that may optimize safety, accuracy, and precision when dissecting challenging low pelvic tumors. (2) Methods: Preoperative CT images were acquired with eight skin-fixed fiducials and loaded into a navigation system. A patient tracker was mounted on the bed side. Patient-to-image paired point registration was performed, and an instrument tracker was mounted on a laparoscopic instrument and calibrated for instrument tracking. Surgical operations were performed with real-time stereotactic navigation assistance. (3) Results: Three patients underwent stereotactic navigation surgery. Fiducial registration errors were good to optimal (±1.9, ±3.4, and ±3.4 mm). Lesions were easily identified and targeted with real-time navigation. Surgeries were uneventful. Histopathology examinations identified one retro-rectal schwannoma, one lateral pelvic recurrence from rectal adenocarcinoma, and one advanced anal canal carcinoma. No navigation-related complications, readmissions, or postoperative mortalities were observed. (4) Conclusions: The application of laparoscopic stereotactic navigation surgery to complex low pelvic tumors is feasible and could impact oncological surgical quality by enabling tumor targeting and ensuring resection margins. Further wider series are needed to confirm stereotactic navigation's impact on challenging low pelvic tumors.

Impact of COVID-19 infection during the postoperative period in patients who underwent gastrointestinal surgery: a retrospective study.

Purpose: The coronavirus disease 2019 (COVID-19) pandemic has led to significant global casualties. This study examines the postoperative impact of COVID-19 on patients who underwent gastrointestinal surgery, considering their heightened vulnerability to infections and increased morbidity and mortality risk. Methods: This retrospective observational study was conducted at a tertiary center and patients who underwent gastrointestinal surgery between January 2022 and February 2023 were included. Postoperative COVID-19 infection was defined as the detection of severe acute respiratory syndrome coronavirus 2 RNA by RT-PCR within 14 days after surgery. Propensity score matching was performed including age, sex, American Society of Anesthesiology physical status classification, and emergency operation between the COVID-19-negative (-) and -positive (+) groups. Results: Following 1:2 propensity score matching, 21 COVID-19(+) and 42 COVID-19(-) patients were included in the study. In the COVID-19(+) group, the postoperative complication rate was significantly higher (52.4% vs. 23.8%, P = 0.023). Mechanical ventilator requirement, intensive care unit (ICU) admission, and readmission rate did not significantly differ between the 2 groups. The median length of ICU (19 days vs. 4 days, P < 0.001) and hospital stay (18 vs. 8 days, P = 0.015) were significantly longer in the COVID-19(+) group. Patients with COVID-19 had a 2.4 times higher relative risk (RR) of major complications than patients without COVID-19 (RR, 2.37; 95% confidence interval, 1.254-4.467; P = 0.015). Conclusion: COVID-19 infection during the postoperative period in gastrointestinal surgery may have adverse outcomes which may increase the risk of major complications. Preoperative COVID-19 screening and protocols for COVID-19 prevention in surgical patients should be maintained.

The impact of a modified microbiota-accessible carbohydrate diet on gut microbiome and clinical symptoms in colorectal cancer patients following surgical resection.

A high-fiber diet is widely recognized for its positive effects on the gut microbiome. However, the specific impact of a high-fiber diet on the gut microbiome and bowel habits of patients with colon cancer remains poorly understood. In this study, we aimed to assess the effects of a modified microbiota-accessible carbohydrate (mMAC) diet on gut microbiota composition and clinical symptoms in colon cancer patients who underwent surgical resection. To achieve this, we enrolled 40 patients in two groups: those who received adjuvant chemotherapy and those who did not. Fecal samples were collected before and after dietary interventions for microbial and metabolite analyses. Each group was randomized in a 1: 1 ratio to follow either a 3-week conventional diet followed by a 3-week mMAC diet, or the reverse sequence. Although there were no significant differences in the microbial diversity data before and after the mMAC diet in both the non-chemotherapy and chemotherapy groups, distinct differences in gut microbial composition were revealed after the mMAC diet. Specifically, the abundance of Prevotella, which is associated with high-fiber diets, was further elevated with increased concentrations of acetate and propionate after the mMAC diet. Additionally, patients who experienced improved diarrhea and constipation after the mMAC diet exhibited an enrichment of beneficial bacteria and notable changes in metabolites. In conclusion, this study provides valuable insights into the potential benefits of the mMAC diet, specifically its impact on the gut microbiome and clinical symptoms in postoperative colorectal cancer (CRC) patients. These findings emphasize the potential role of a high-fiber diet in influencing the gut microbiome, and the clinical symptoms warrant further investigation.

Conversational artificial intelligence (chatGPT™) in the management of complex colorectal cancer patients: early experience.

INTRODUCTION: In 2022 chatGPT™ (OpenAI, San Francisco) was introduced to the public. The complex reasoning and the natural language processing (NLP) ability of the AI platform has generated much excitement about the potential applications. This study conducted a preliminary analysis of the chatGPT™'s ability to formulate a management plan in accordance with oncological principles for patients with colorectal cancer. METHODOLOGY: Colorectal cancer cases discussed in the multidisciplinary tumor (MDT) board at a single tertiary institution between September 2022 and January 2023 were prospectively collected. The treatment recommendations made by the chatGPT™ for Stage IV, recurrent, synchronous colorectal cancer were analysed for adherence to oncological principles. The recommendations by chatGPT™ were compared with the decision plans made by the MDT. RESULTS: In all cases, the chatGPT™ was able to adhere to oncological principles. The recommendations in all 30 cases factored in the patient's overall health and functional status. The oncological management recommendation concordance rate between chatGPT™ and the MDT was 86.7%. CONCLUSIONS: This study shows a high concordance rate of the chatGPT™'s recommendations with that given by the MDT in the management of complex colorectal patients. This will need to be verified in a larger prospective study.

Recurrence Patterns and Risk Factors after Curative Resection for Colorectal Cancer: Insights for Postoperative Surveillance Strategies.

This study aimed to assess recurrence patterns and related risk factors following curative resection of colorectal cancer (CRC). This retrospective observational study was conducted at a tertiary care center, including 2622 patients with stage I-III CRC who underwent curative resection between 2008 and 2018. Hazard rates of recurrence were calculated using a hazard function. The primary outcome was the peak recurrence time after curative resection and secondary outcomes were prognostic factors associated with recurrence. Over a median follow-up period of 53 months, the overall, locoregional and systemic recurrence rates were 8.9%, 0.7%, and 8.5%, respectively. Recurrence rates were significantly higher for rectal cancer (14.9% overall, 4.4% locoregionally, and 12.3% systemically) than for colon cancer (all p < 0.001). The peak recurrence time was 11 months, with variations in hazard rates and curves depending on the tumor location, stage, and risk factors. Patients with AL or CRM involvement exhibited a distinct pattern, with a high hazard rate in the early postoperative period. Understanding these recurrence patterns and risk factors is crucial for establishing effective postoperative surveillance strategies. Our findings suggested that short-interval surveillance should be considered during the first 2 years post-surgery, particularly for high-risk patients who should receive early attention.

Diagnostic Accuracy of Carcinoembryonic Antigen (CEA) in Detecting Colorectal Cancer Recurrence Depending on Its Preoperative Level.

BACKGROUND: Serum carcinoembryonic antigen (CEA) increase in patients with colorectal cancer (CRC) recurrence was observed to vary depending on their initial values. This study aimed to evaluate the diagnostic accuracy of CEA for detecting CRC recurrence in patients with normal and elevated initial CEA levels. METHODS: A total of 261 CRC recurrence patients who underwent curative resection were included and divided into two groups, normal and elevated initial CEA. Analysis was performed comparing patient, tumor, and recurrence characteristics retrospectively. RESULTS: There were 192 patients with normal and 69 with high initial CEA levels. Patient and tumor characteristics were similar. Eighty-six patients had elevated CEA at the time of recurrence, and the overall sensitivity of CEA for recurrence was 33.0%. In the high initial CEA group, 59.4% exhibited increased CEA level at recurrence, whereas in patients with normal initial CEA levels, only 23.4% showed elevated levels (p < 0.001). Patients with both high CEA preoperatively and at recurrence had more local recurrence, but there was no statistical significance (p = 0.053), and the rate of lung metastasis was higher in patients whose CEA remained normal at recurrence (38.3% vs. 24.4%, p = 0.026). The overall survival of patients with elevated CEA at recurrence was worse than those with normal CEA levels (56.9% vs. 42.4%, p = 0.003). CONCLUSION: The diagnostic accuracy of CEA for detecting recurrence depends on initial CEA level. Regardless of the initial CEA level, elevation at recurrence was significantly associated with overall survival in patients with recurrent CRC.

Effectiveness of personalized treatment stage-adjusted digital therapeutics in colorectal cancer: a randomized controlled trial.

BACKGROUND: Colorectal cancer survivors often experience decline in physical performance and poor quality of life after surgery and during adjuvant therapies. In these patients, preserving skeletal muscle mass and high-quality nourishment are essential to reduce postoperative complications and improve quality of life and cancer-specific survival. Digital therapeutics have emerged as an encouraging tool for cancer survivors. However, to the best of our knowledge, randomized clinical trials applying personalized mobile application and smart bands as a supportive tool to several colorectal patients remain to be conducted, intervening immediately after the surgical treatment. METHODS: This study is a prospective, multi-center, single-blinded, two-armed, randomized controlled trial. The study aims to recruit 324 patients from three hospitals. Patients will be randomly allocated to two groups for one year of rehabilitation, starting immediately after the operation: a digital healthcare system rehabilitation (intervention) group and a conventional education-based rehabilitation (control) group. The primary objective of this protocol is to clarify the effect of digital healthcare system rehabilitation on skeletal muscle mass increment in patients with colorectal cancer. The secondary outcomes would be the improvement in quality of life measured by EORTC QLQ C30 and CR29, enhanced physical fitness level measured by grip strength test, 30-sec chair stand test and 2-min walk test, increased physical activity measured by IPAQ-SF, alleviated pain intensity, decreased severity of the LARS, weight, and fat mass. These measurements will be held on enrollment and at 1, 3, 6 and 12 months thereafter. DISCUSSION: This study will compare the effect of personalized treatment stage-adjusted digital health interventions on immediate postoperative rehabilitation with that of conventional education-based rehabilitation in patients with colorectal cancer. This will be the first randomized clinical trial performing immediate postoperative rehabilitation in a large number of patients with colorectal cancer with a tailored digital health intervention, modified according to the treatment phase and patient condition. The study will add foundations for the application of comprehensive digital healthcare programs focusing on individuality in postoperative rehabilitation of patients with cancer. TRIAL REGISTRATION: NCT05046756. Registered on 11 May 2021.

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.

Laparoscopic D3 oncological resection in splenic flexure cancer: Technical details and its impact on long-term survival.

AIM: The applicability of laparoscopic D3 oncological resection for splenic flexure cancer (SFC) surgery has not been fully explored due to technical difficulties and variations in surgical procedure. The aim of this work is to describe the feasibility of performing laparoscopic D3 resection in SFC and its impact on long-term survival. METHOD: A retrospective study on 47 out of 52 consecutive patients who underwent elective laparoscopic colectomy for SFC from December 2006 until December 2019 at Korea University Anam Hospital was performed. Data on patients' demographic and clinical features, surgical procedures, intraoperative and postoperative complications, pathological features and follow-up were collected. Categorical data are expressed as frequencies (n) and percentages (%). Continuous data are expressed as mean ± standard deviation and median (range). The Kaplan-Meier test was used to determine the overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS). RESULTS: The median age of patients was 67.0 years (range 27-87 years) and 72.3% were men. Ten (21.3%) patients presented with an obstructing tumour and underwent an elective laparoscopic colectomy, while 68.1% of patients presented with Stage II and III disease. The conversion rate was 4.3% and the morbidity rate was 31.9%. There was one postoperative death secondary to splenic infarction and anastomotic leak leading to multi-organ failure. Four deaths occurred due to disease progression during a median follow-up of 63.8 months. The rate of recurrence was 20%, the 5-year OS was 89.6% and the 5-year PFS was 72.9%. After R0 resection, the 5-year OS was 91.5% and the 5-year DFS was 74.5%. CONCLUSION: Laparoscopic D3 colectomy for SFC is feasible, with an acceptable morbidity and long-term oncological outcome when performed by highly skilled laparoscopic colorectal surgeons with knowledge of the complex anatomy around the splenic flexure. Further randomized trials should be performed to determine the advantage of laparoscopic D3 colectomy over conventional colectomy for SFC.

Laparoscopic Extraperitoneal Approach for Lateral Pelvic Node Dissection in Rectal Cancer: Techniques and Short-Term Outcomes.

BACKGROUND: Lateral pelvic lymph node dissection has been performed selectively in rectal cancer cases; however, it involves highly skilled techniques because of the complex adjacent anatomical structures. MATERIALS AND METHODS: Laparoscopic EP-LPND was performed in Korea University Anam Hospital from June 2018, and short-term surgical outcomes were analyzed from June to December 2018. Among the patients with histologically diagnosed rectal adenocarcinoma, patients who were suspected Lateral pelvic lymph node metastasis at magnetic resonance imaging were selected for this procedure. RESULTS: Seven patients underwent laparoscopic extraperitoneal approach for lateral pelvic lymph node dissection in the study period. The mean number of retrieved lymph node was 4.57, and metastatic lymph nodes were identified in 3 patients (42.8%). All of the lymph nodes with suspected metastasis preoperatively were removed in postoperative images. There was no immediate postoperative complication beyond the moderate grade associated with lateral pelvic lymph node dissection. The median follow-up was 9 months, and there were no local recurrence nor complications related to sexual and voiding functions. CONCLUSIONS: The laparoscopic extraperitoneal approach might be an efficient way to perform lateral pelvic lymph node dissection using the same principles as the conventional method without violation of the peritoneum.

FDG metabolic parameter-based models for predicting recurrence after upfront surgery in synchronous colorectal cancer liver metastasis.

OBJECTIVE: This study aimed to develop and validate post- and preoperative models for predicting recurrence after curative-intent surgery using an FDG PET-CT metabolic parameter to improve the prognosis of patients with synchronous colorectal cancer liver metastasis (SCLM). METHODS: In this retrospective multicenter study, consecutive patients with resectable SCLM underwent upfront surgery between 2006 and 2015 (development cohort) and between 2006 and 2017 (validation cohort). In the development cohort, we developed and internally validated the post- and preoperative models using multivariable Cox regression with an FDG metabolic parameter (metastasis-to-primary-tumor uptake ratio [M/P ratio]) and clinicopathological variables as predictors. In the validation cohort, the models were externally validated for discrimination, calibration, and clinical usefulness. Model performance was compared with that of Fong's clinical risk score (FCRS). RESULTS: A total of 374 patients (59.1 ± 10.5 years, 254 men) belonged in the development cohort and 151 (60.3 ± 12.0 years, 94 men) in the validation cohort. The M/P ratio and nine clinicopathological predictors were included in the models. Both postoperative and preoperative models showed significantly higher discrimination than FCRS (p < .05) in the external validation (time-dependent AUC = 0.76 [95% CI 0.68-0.84] and 0.76 [0.68-0.84] vs. 0.65 [0.57-0.74], respectively). Calibration plots and decision curve analysis demonstrated that both models were well calibrated and clinically useful. The developed models are presented as a web-based calculator ( https://cpmodel.shinyapps.io/SCLM/ ) and nomograms. CONCLUSIONS: FDG metabolic parameter-based prognostic models are well-calibrated recurrence prediction models with good discriminative power. They can be used for accurate risk stratification in patients with SCLM. KEY POINTS: • In this multicenter study, we developed and validated prediction models for recurrence in patients with resectable synchronous colorectal cancer liver metastasis using a metabolic parameter from FDG PET-CT. • The developed models showed good predictive performance on external validation, significantly exceeding that of a pre-existing model. • The models may be utilized for accurate patient risk stratification, thereby aiding in therapeutic decision-making.

Robotic approach may be associated with a lower risk of lung metastases compared to laparoscopic approach for mid-low rectal cancer after neoadjuvant chemoradiotherapy: a multivariate analysis on long-term recurrence patterns.

PURPOSE: Describe differences on recurrence patterns of mid-low rectal cancers treated with neoadjuvant chemoradiotherapy and low anterior resection between laparoscopic and robotic approach. METHODS: Patients were identified from a prospectively maintained institutional database between 2006 and 2019. Demographics, clinicopathological features, recurrence, and survival were investigated. Cox regression analysis was performed for risk factor analysis. RESULTS: A total of 160 patients (36 laparoscopic and 124 robotic) were included. Systemic recurrence rate was higher in laparoscopic group (27.8 vs 12.1%, p = 0.023). Liver recurrence was similar (11.1 vs 4.0%). Lung recurrence was higher after laparoscopy (19.4 vs 6.5%, p = 0.019). Time to lung recurrence was shorter after laparoscopy (13.0 months, IQR 4.0-20.0) compared to robotic (23.5 months, IQR 17.0-42.7) with no statistical significance. Time to liver recurrence was similar between laparoscopy (19.5 months, IQR 4.7-37.5) and robotic (19.0 months, IQR 10.5-33.0). Median overall survival after lung recurrence was different (p = 0.021) between laparoscopy (19.0 months, IQR 16.0-67.0) and robotic (74.0 months, IQR 50.2-112.2). OS after liver recurrence was similar between groups. Overall survival and lung disease-free survival were different between the two groups (p = 0.032 and p = 0.020), while liver disease-free survival and local recurrence-free survival were not. Laparoscopy (p = 0.030; HR 3.074, 95% CI: 1.112-8.496) was a risk factor for lung disease-free survival on multivariate analysis. CONCLUSION: Lung recurrences were less frequent and with better overall survival in the robotic group. Liver recurrences were not influenced by choice of approach. Trials are needed to investigate why the robotic approach affects distant metastasis control.

Effect of a Patient Blood Management system on perioperative transfusion practice and short-term outcomes of colorectal cancer surgery.

BACKGROUND: Patients undergoing colorectal cancer surgery may require a blood transfusion. However, blood transfusions are associated with postoperative complications and long-term oncologic outcomes. Patient blood management (PBM) is an evidence-based multimodal approach for blood transfusion optimisation. We sought to investigate the effects of PBM implementation in blood transfusion practice and on short-term postoperative outcomes. MATERIALS AND METHODS: This study retrospectively reviewed data from 2,080 patients who had undergone colorectal cancer surgery at a single centre from 2015 to 2020. PBM was implemented in 2018, and outcomes were compared between the pre-PBM (2015-2017) and the post-PBM (2018-2020) periods. RESULTS: A total of 951 patients in the pre-PBM group and 1,129 in the post-PBM group were included. The transfusion rate of the total number of packed red blood cells (PRBCs) used decreased after PBM implementation (16.3 vs 8.3%; p<0.001). The rate of appropriately transfused PRBCs increased from the pre-PBM period to the post-PBM period (42 vs 67%; p<0.001). There was no significant difference in rates of complications between the two groups (23.0 vs 21.5%; p=0.412); however, a reduction in both anastomosis leakage (5.8 vs 3.7%; p=0.026) and the length of stay after surgery (LOS) (10.3±11.2 vs 8.2±5.7 days; p<0.001) was reported after PBM implementation. DISCUSSION: The PBM programme optimised the transfusion rate in patients undergoing colorectal cancer surgery. Implementation of the PBM programme had a positive effect on postoperative length of stay and anastomosis leakage while no increase in the risk of other complications was reported.

Quality of laparoscopic camera navigation in robot-assisted versus conventional laparoscopic surgery for rectal cancer: An analysis of surgical videos through a video processing computer software.

BACKGROUND: To compare laparoscopic camera navigation (LCN) quality between robot-assisted laparoscopic surgery (RALS) and conventional laparoscopic surgery (CLS). METHODS: 20 recordings were selected by propensity score matching and subjected to Python® software to generate single frames at one second intervals. For each frame, the pixel where the camera should be centred, based on instrument position, current action (dissection/haemostasis/traction) in the frame, was detected. LCN quality was reviewed by two independent surgeons to evaluate erroneous LCN. RESULTS: RALS had higher incidence of centred views (83.1 ± 4.02% vs. 76.0 ± 2.38%, p < 0.05) and a shorter distance between actual and optimal frame centres (123.3 ± 9.8 vs. 144.8 ± 13.9, p < 0.05) compared to CLS. Erroneous camera navigations were more frequent in CLS regarding total time of horizontal alignment failure (2.1 ± 2.2 vs. 6.0 ± 5.4 min, p = 0.063) and number of excessive zoom-in visualization (0.1 ± 0.3 vs. 1.9 ± 1.4, p = 0.003). CONCLUSIONS: RALS provided higher LCN quality than did CLS, emphasising the benefits of a surgeon-controlled view.

Lower Incidence of Postoperative Urinary Retention in Robotic Total Mesorectal Excision for Low Rectal Cancer Compared with Laparoscopic Surgery.

INTRODUCTION: The incidence and clinical significance of postoperative urinary retention (POUR) remain high. This study aimed to evaluate the incidence of POUR and related risk factors in patients who underwent total mesorectal excision (TMR) for low rectal cancer. METHODS: This study is a retrospective review of a prospectively collected colorectal database from a single center. Data from patients who underwent surgery for low rectal cancer between September 2006 and May 2017 were analyzed to assess the risk factors of POUR. POUR was considered inability to void after urinary catheter removal requiring catheter reinsertion and difficulty in bladder emptying requiring intermittent catheterization. RESULTS: Of 555 patients with low rectal cancer, 78 (14.1%) developed POUR. Based on multivariate logistic regression analysis, laparoscopic TMR (odds ratio [OR]; 2.114, 95% confidence interval [CI]; 1.212-3.689, p = 0.008) and postoperative ileus (OR; 2.389, 95% CI; 1.282-4.450, p = 0.006) were independent risk factors of POUR. Male gender, advanced age, neoadjuvant chemoradiation, longer operative time, abdominoperineal resection, and lateral pelvic lymph node dissection were not associated with POUR. Advanced age over 65 years also failed to show statistical significance (OR; 1.604, 95% CI; 0.965-2.668, p = 0.068). CONCLUSION: Laparoscopic approach and postoperative ileus are risk factors for POUR after low rectal cancer surgery. We postulate that the benefits of robotic surgical systems compared to a laparoscopic approach may reduce the incidence of POUR.

Characteristics and outcomes of colorectal cancer surgery by age in a tertiary center in Korea: a retrospective review.

PURPOSE: Colorectal cancer (CRC) occurs in all age groups, and the application of treatment may vary according to age. The study was designed to identify the characteristics of CRC by age. METHODS: A total of 4,326 patients undergoing primary resection for CRC from September 2006 to July 2019 were reviewed. Patient and tumor characteristics, operative and postoperative data, and oncologic outcome were compared. RESULTS: Patients aged 60 to 69 years comprised the largest age group (29.7%), followed by those aged 50 to 59 and 70 to 79 (24.5% and 23.9%, respectively). Rectal cancer was common in all age groups, but right-sided colon cancer tended to be more frequent in older patients. In very elderly patients, there were significant numbers of emergency surgeries, and the frequencies of open surgery and permanent stoma were greater. In contrast, total abdominal colectomy or total proctocolectomy was performed frequently in patients in their teens and twenties. The elderly patients showed more advanced tumor stages and postoperative ileus. The incidence of adjuvant treatment was low in elderly patients, who also had shorter follow-up periods. Overall survival was reduced in older patients with stages 0 to 3 CRC (P<0.001), but disease-free survival did not differ by age (P=0.391). CONCLUSION: CRC screening at an earlier age than is currently undertaken may be necessary in Korea. In addition, improved surgical and oncological outcomes can be achieved through active treatment of the growing number of elderly CRC patients.

A Minimally Invasive Pelvic Multivisceral Resection Approach for Locally Advanced Primary Colorectal Cancers: A Single-Institution Experience.

Background: The role of minimally invasive surgery (MIS) in locally advanced colorectal cancers (CRCs) suspected of direct invasion to adjacent organs or structures remains controversial. The aim of this study is to verify the safety and feasibility of minimally invasive multivisceral resection (MVR) surgery for locally advanced CRCs compared with conventional open surgery. Materials and Methods: Prospectively collected data from patients who underwent MVR for locally advanced CRCs from 2007 to 2017 were retrospectively reviewed. Patients with preoperative clinically suspected T4b stage cancers were enrolled in the study. Results: There were 30 and 19 patients in the MIS and open surgery groups, respectively. Seven patients in the MIS group required conversion, and the most common reason for conversion was ureter and bladder invasion. Tumor sizes were significantly larger in the open group (5.46 cm versus 7.48 cm, P = .010), whereas the MIS group included more patients with rectal cancers (56.7% versus 21%, P = .021). No differences were observed between the two groups in terms of operation time, estimated blood loss, and postoperative hospital stay. Curative (R0) resection was achieved in all patients, and the median follow-up period was 23 months. The 3-year overall survival in the MIS group was 73.6% and 77.9% in the open group (P = .445), and the 3-year total disease-free survival (DFS) was 59.2% and 51.4%, respectively (P = .695). Three-year local DFS was 83.3% for the MIS group, and 51.4% for the open group (P = .120). Conclusion: MIS for primary T4b CRCs without urinary tract invasion is safe and feasible.

Laparoscopic en bloc lateral pelvic exenteration for locally advanced and recurrent rectal cancer.

This study describes minimally invasive lateral pelvic compartment en bloc excision for rectal cancer.