Colic Artery Research Articles

Three-dimensional Computed Tomography Evaluation of the Vasculature of Right-side Colon Cancer.

From an oncological perspective, central ligation of the feeding vessel is an important approach to consider when performing colon cancer surgery. This study aimed to use three-dimensional computed tomography (3D-CT) to clarify the vascular anatomy for performing central vascular ligation to improve the accuracy of minimally invasive surgery (MIS) performed to treat advanced right-side colon cancer. This descriptive study was conducted at one institution and targeted 92 patients with right-side colon cancer whose vascular anatomy was evaluated with 3D-CT before surgery between January 2014 and December 2020 at Tokyo Medical University Hospital. In 49 patients (53.3%), the ileocolic artery was ventral to the superior mesenteric vein (SMV), whereas in 43 patients (46.7%), it was dorsal to the SMV. The right colic artery was present in 31 patients (33.7%). The middle colic artery was present in all patients (100%). A common duct type was present in 80 patients (87.0%). Branching directly from the superior mesenteric artery without a common duct was observed in 12 patients (13.0%). Twenty-one patients (22.9%) had an accessory superior mesenteric artery. The vascular structure of the right-side colon is highly complex. Conducting 3D-CT evaluations of the vessel anatomy is very useful for surgeons who conduct MIS, and is considered to enable central ligation to be performed safely and improve the quality of surgery, which will benefit patients.

Open Management of an Asymptomatic 4.2Cm Middle Colic Artery Aneurysm and Liteture Review.

Aneurysms of the middle colic artery (MCAA) and its branches are exceedingly rare accounting for <3% of total visceral aneurysms. Very few MCAA cases have been reported in the literature with only three cases accounting for a diameter >4cm. We describe the successful open repair with ligation of a 4.2cm asymptomatic MCAA in a female patient through the gastrohepatic ligament taking meticulous caution to avoid injury of the pancreas. The postoperative period was uneventful and the patient was discharged from the hospital on the fifth postoperative day. At 1month follow-up the postoperative computed tomographic angiography documented complete exclusion of the MCAA and absence of contrast agent in the sac both in the arterial and the venous phase. While the endovascular treatment is the first-line option for visceral aneurysms, the open approach is still reserved for certain cases of hostile anatomy, challenging location and large size. Our case highlights the irreplaceable role of open surgery and underlines the collaboration between surgical specialties.

High Ligation of the Inferior Mesenteric Artery in Left-Sided Colon and Rectal Cancer Resection: Rates of Success and Outcomes.

High ligation of the inferior mesenteric artery, defined as ligation before the takeoff of the left colic artery, is often described as the gold standard in low left-sided colon and rectal cancer surgery. The aim of this study is to quantify the rate of ligation at the described level at a single academic center. Additionally, we examined the relationship between level of ligation and cancer-related outcomes. This retrospective cohort study included patients ages 18 and over with low left-sided colon, rectal, and anal cancers undergoing surgical resection. Radiographic evidence of high ligation was defined as ligation of the inferior mesenteric artery before the takeoff of the left colic artery. Patients with and without radiographic evidence of high ligation on CT were compared. Secondary outcomes include lymph node yield and positivity, need for adjuvant therapy, and time from surgery to adjuvant therapy. 169 patients (54% male) were included in the study. 61.5% of operative reports described high ligation of the IMA. There was radiographic evidence of high ligation in 55.6% of total patients and in 70.2% of patients where high ligation was intended. There was no significant difference in surgeon experience, surgical procedure, or surgical approach. There was no difference in lymph node yield, time to adjuvant chemotherapy, or recurrence rates. This study demonstrates good technical success rate of high ligation of the inferior mesenteric artery but shows no difference in short-term patient-measured outcomes between high and low ligation (or successful and unsuccessful high ligation).

Variant origins of the middle colic artery from the coeliac trunk and its branches.

The middle colic artery usually arises from the superior mesenteric artery, but in rare cases it may arise from the coeliac trunk or its branches. The aim of this study was to investigate variant origins of the middle colic artery on computed tomography and anatomical dissection. Variant middle colic arteries were identified on computed tomography as part of an ongoing study investigating anatomical variations of vessels of the upper abdomen. Three-dimensional reconstructions were made to demonstrate the variant findings. Cadaveric dissections were performed as part of a routine dissection course. We report five cases of rare variant origins of the middle colic artery arising from the coeliac axis. Among these sites of origin were the coeliac trunk, the gastrosplenic trunk, the splenic artery, and the common hepatic artery. Four cases were identified on multi-detector computed tomography and one in a cadaver. In all cases, the vessels passed posterior to the body of the pancreas before entering the transverse mesocolon. Knowledge of middle colic artery variations is important to prevent inadvertent injury in digestive surgery, especially in the hepatopancreatic area. Variant origins of the middle colic artery are rare, and their knowledge is crucial to prevent unnecessary iatrogenic injury during abdominal surgery.

Risk assessment of rectal anastomotic leakage (RAREAL) after DIXON in non-emergency patients with rectal cancer

BackgroundThe routine establishment of a diverting stoma (DS) remains controversial in every patient undergoing Dixon operation. We aimed to establish a model for the risk assessment of rectal anastomotic leak (RAREAL) after Dixon in non-emergency patients with rectal cancer, using routinely available variables, by which surgeons could individualize their approach to DS.Methods323 patients who underwent Dixon operation for rectal cancer from January 2015 to December 2018 were taken as the model group for retrospective study. Univariable and multivariable logistic regression analysis was used to determine the independent risk factors associated with anastomotic leakage. We constructed the RAREAL model. 150 patients who underwent Dixon operation due to rectal cancer from January 2019 to December 2020 were collected according to the uniform criteria as a validation group to validate the RAREAL model.ResultsIn the model group, multivariable analysis identified the following variables as independent risk factors for AL: HbA1c (odds ratio (OR) = 4.107; P = 0.044), Left colic artery (LCA) non preservation (OR = 4.360; P = 0.026), Tumor distance from the anal margin (TD) (OR = 6.373; P = 0.002). In the model group, the area under the curve (AUC) of the receiver operating characteristic (ROC) for evaluating AL with RAREAL was 0.733, and when RAREAL score = 2.5, its sensitivity, specificity and Youden index were 0.385, 0.973, 0.358, respectively. The AUC was 0.722 in the validation group and its sensitivity and specificity were 0.333 and 0.985, respectively, when RAREAL score = 2.5.ConclusionThe RAREAL score can be used to assess the risk of AL after Dixon operation for rectal cancer, and prophylactic DS should be proactively done when the score is greater than 2.5.

Level of Inferior Mesenteric Artery Ligation in Sigmoid Colon and Rectal Cancer Surgery: Analysis of Apical Lymph Node Metastasis and Recurrence

Introduction: Whether high or low ligation of the inferior mesenteric artery (IMA) is optimal for treating sigmoid colon and rectal cancers is controversial. The present study aimed to compare outcomes of high and low ligation of the IMA and determine the adequate extent of IMA lymph node dissection. Methods: Subjects were 455 consecutive stage I–III colorectal cancer patients who underwent curative surgery between 2011 and 2019. We assessed the association between the level of IMA ligation and overall survival and recurrence-free survival (RFS) by propensity score matching analysis. Clinicopathological features of IMA lymph node metastasis and recurrence patterns were analyzed. Results: After propensity score matching, the low ligation group had a significantly worse prognosis than that of the high ligation group for RFS (p = 0.039). Positive IMA lymph nodes were associated with pathological T3 or T4 stage and N2 stage. IMA lymph node recurrences in the high ligation group occurred at the superior left side of the IMA root. In contrast, all recurrences in the low ligation group occurred at the left colic artery bifurcation. Conclusion: High ligation of IMA is oncologically safe. However, even with high ligation, care must be taken to ensure adequate lymph node dissection.

Surgical anatomy of the dorsal pancreatic artery: Considering embryonic development

ObjectivesThe dorsal pancreatic artery (DPA) is a pancreatic branch with various anatomical variations. Previous studies mostly focused on the origin of the DPA, and its pathways and branching patterns have rarely been examined. The purpose of this study was to investigate the branching patterns and pathways of the DPA. MethodsThis study included 110 patients who underwent computed tomography scans. We examined the pathways and branching patterns of the DPA. ResultsThe DPA was identified in 101 patients (92%), and originated from the splenic artery in 30 patients (31%), the common hepatic artery in 17 patients (17%), the celiac trunk in 10 patients (10%), the superior mesenteric artery in 27 patients (27%), the replaced right hepatic artery in 7 patients (7%), the inferior pancreaticoduodenal artery in 5 patients (5%), and other arteries in 3 patients (3%). Four distinct types of branches were identified as follows: the superior branch (32%), the inferior branch (86%), the right branch (80%), and the accessory middle colic artery (12%). Additionally, the arcs of Buhler and Riolan were observed in two patients each and their anastomotic vessels followed almost the same pathway as the DPA. ConclusionA number of variations of the DPA were observed with regard to its origin and branching pattern; however, the DPA and its branches always ran along the same pathway, as summarized in Fig. 4. The anatomical information gained from this study may contribute to performing safe pancreatic resections.

Revisited Surgical Anatomy of the Left Colonic Angle for Tailored Carcinologic Colectomy: A Review.

Although several types of surgical procedure have been advocated to date, the optimal resection of the left colonic angle in cancer treatment remains controversial. Located at the border of the transverse and descending colons, the anatomy of the left colonic angle is complex and characterized by numerous anatomic variations. Recent advances in preoperative (three-dimensional CT angiography with colonography) and/or intraoperative (indocyanine green staining) imaging have allowed for a better identification of these variations. We performed a methodological review of studies assessing the anatomical variations of the left colic artery. While the left colonic angle is classically vascularized by branches of the superior and inferior mesenteric arteries, an accessory middle colonic artery has been identified from 6 % to 36% of cases, respectively, leading to their classification of five types. In the absence of a left colic artery, this artery becomes predominant. In parallel to the variations in the venous drainage of the left colonic angle, which has been classified into four types, new lymphatic drainage routes have also been identified via this accessory artery and the inferior mesenteric vein. Collectively, these newly obtained findings plead for preoperative identification in cases of cancer of the left colonic angle and a surgical strategy adapted to these anatomical variations.

Membrane anatomy in right colon cancer: definition and identification of mesocolic completeness

Complete mesocolic excision (CME) and D3 resection of right colon cancer have been widely implemented, but the definition and identification of the completeness of the mesentery have not been fully agreed, especially the dorsal and medial borders. In this paper, we proposed the dorsal fascia of the colonic mesentery as the dorsal border of the mesocolon and the line connecting the roots of the ileocolic artery and the middle colic artery (ICA-MCA line) as the medial border of the CME by systematically studying the relationship between the mesentery and the mesenteric bed from the theory of membrane anatomy, combined with surgical experience and in-depth review of ontogenetic anatomy. We also proposed the visible "superior mesenteric vein notch" and "middle colic artery triangle" on surgical specimens as identifiers of mesocolic completeness.

Risk factors, quality of life, and oncological effects of refractory anastomotic leakage for laparoscopic intersphincteric resection.

Refractory anastomotic leakage (RAL) after intersphincteric resection (ISR) usually leads to failure of protective stoma reversal in ultralow rectal cancers. The aim of this study is to assess the risk factors and oncological outcomes of both anastomotic leakage (AL) and RAL, and quality of life (QoL) of RAL after laparoscopic ISR (LsISR). A total of 371 ultralow rectal cancer patients with LsISR were enrolled from a tertiary colorectal surgery referral center. Risk factors for AL and RAL were identified by logistic regression. Three-year disease-free survival (DFS) of AL and RAL was analyzed by the Cox regression. QoL of RAL group (compared with non-RAL group) was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-CR29 questionnaires. The rates of AL and RAL after LsISR accounted for 8.4% (31/371) and 4.6% (17/371) in this cohort, respectively. Non-left colic artery preservation (odds ratio [OR]=3.491, P=0.009), neoadjuvant chemoradiotherapy (nCRT) (OR=6.038, P<0.001), and lower anastomosis height (OR=5.271, P=0.010) were independent risk factors for AL, while nCRT (OR=11.602, P<0.001) was the only independent risk factor for RAL. Male (hazard ratio [HR]=1.989, P=0.014), age>60years (HR=1.877, P=0.018), and lymph node metastasis (HR=2.125, P=0.005) were independent risk factors of poor 3-year DFS, but not RAL (P=0.646). RAL patients have significantly worse global health status, worse emotional and social function scores at the late postoperative stage, and worse urinary and sexual function at the early postoperative stage (all P<0.05). Neoadjuvant chemoradiotherapy was an independent risk factor for RAL after LsISR. RAL shows similar oncological outcomes, but with poor QoL.

Safety and efficacy of left colic artery preservation in laparoscopic anterior resection for lower rectal cancer.

Background: To evaluate the safety and efficacy of left colic artery (LCA) preservation in laparoscopic anterior resection with D3 lymphadenectomy for lower rectal cancer. Methods: A total of 117 patients with lower rectal cancer who received laparoscopic anterior resection were retrospectively analyzed. Results: No differences were detected in terms of the numbers of harvested lymph nodes and metastatic lymph nodes, the intraoperative and postoperative complications or the postoperative recurrence and survival rates between the two groups (p>0.05), but the LCA preservation group showed a lower anastomotic leakage rate than the LCA nonpreservation group (2/49 vs 12/68). Conclusion: LCA preservation may help reduce the incidence of anastomotic leakage without impairing surgical and oncological outcomes.

Oncological Impact of the Level of Inferior Mesenteric Artery Ligation in Low Rectal Cancer Surgery.

This study aimed to evaluate the clinical impact of the level of inferior mesenteric artery (IMA) ligation in patients with advanced low rectal cancer. All enrolled patients (n=350) underwent curative resection of rectal cancer with D3 lymph node dissection, with either IMA (high-tie) or superior rectal artery (SRA) (low-tie) ligation. There were 27 and 65 patients in the high-tie and low-tie groups, respectively. There was no significant difference in the postoperative complication rate. Postoperative anastomotic leakage developed in five patients in the low-tie group and none in the high-tie group. The overall recurrence rates were 37.0% (n=10) and 40.0% (n=26) in the high-tie and low-tie groups, respectively, with no significant difference between the two groups (p=0.748). Local recurrences and lymph node metastases developed in five and no patients in the high-tie group and in 13 and one patient in the low-tie group, respectively. In the multivariate analysis, pathological T4 and pathological N2 and N3 were independent poor prognostic factors for overall survival (OS), whereas left colic artery (LCA) preservation was not significant. No significant difference in oncological outcomes was observed in advanced low rectal cancer surgery with respect to the level of the IMA ligation. Thus, the less complicated high-tie procedure should be adopted as a standard procedure.

Application of a three-dimensional printed pelvic model in laparoscopic radical resection of rectal cancer.

To investigate the application value of a three-dimensional (3D) printed pelvic model in laparoscopic radical resection of rectal cancer. Clinical data of patients undergoing laparoscopic radical rectal cancer surgery in The Second People's Hospital of Lianyungang City from May 2020 to April 2022 were selected. Patients were randomly divided into general imaging examination group (control group, n=25) and 3D printing group (observation group, n=25) by random number table method, and the perioperative situation of patients in the two groups was compared. There was no significant difference in general data between the two groups (p>0.05). Operation time, intraoperative blood loss, intraoperative time to locate inferior mesenteric artery, intraoperative time to locate left colic artery, first postoperative exhaust time and length of hospital stay in the observation group were all lower than those in the control group (P < 0.05); There were no significant differences in the total number of lymph nodes and complications between the two groups (P > 0.05). The application of 3D printed pelvic model in laparoscopic radical resection of rectal cancer is conducive to understanding pelvic structure and mesenteric vascular anatomy, reducing intraoperative bleeding and shortening operation time, which is worthy of further clinical application.

Vascular anatomical study of persistent descending mesocolon in patients undergoing laparoscopic surgery for colorectal cancer.

Persistent descending mesocolon (PDM) is a rare congenital atypia of fixation of the descending colon, and currently, very few detailed studies exist on its vascular anatomy. This study was conducted to evaluate the features of the vascular anatomy of PDM to help avoid intraoperative lethal injury and subsequent postoperative complications in laparoscopic colorectal surgery. We retrospectively analyzed the data of 534 patients who underwent laparoscopic left-sided colorectal surgery. PDM was diagnosed using preoperative axial computed tomography (CT) view. The vascular anatomical features were compared between PDM and non-PDM cases based on three-dimensional (3D)-CT angiography findings. Additionally, the perioperative short-term outcomes of laparoscopic surgery in the 534 patients were also compared between PDM and non-PDM cases. Of the total 534 patients, 13 patients (2.4%) presented with PDM. No branching pattern of the inferior mesenteric artery (IMA) specific to PDM was found. In the running direction of the IMA and sigmoidal colic artery (SA), the midline-shift of IMA and the right-shift of SA were significantly more in PDM than in non-PDM cases, respectively (38.5% vs. 2.5%, P ≤ .0001; 61.5% vs. 4.6%, P ≤ .0001). The perioperative short-term outcomes of laparoscopic surgery in the 534 patients were similar between PDM and non-PDM cases. Because changes in the direction of the vascular running are often observed due to adhesions and shortening of the mesentery in PDM cases, performing a detailed preoperative evaluation of vascular anatomy using imaging modalities such as 3D-CT angiography is important.

Technical features in preservation of the left colic artery in colorectal oncologic surgery

Technical features in preservation of the left colic artery in colorectal oncologic surgery

A multicenter prospective observational study of lymph node metastasis patterns and short-term outcomes of extended lymphadenectomy in right-sided colon cancer.

The lymph node metastasis rate in right-sided colon cancer is unknown, and the optimal central vascular ligation level remains controversial. We aimed to determine the lymph node metastasis rate and short-term results of radical surgery with extended lymph node dissection in right-sided colon cancer. This prospective multicenter observational study included patients with stage II/III right-sided colon cancer from five cancer hospitals. The metastasis rate of each node station was analyzed according to tumor location and main feeding artery. Between April 2018 and August 2021, 208 patients underwent dissection around the superior mesenteric artery (SMA) and vein (SMV). In transverse colon cancer, 7.5% and 2.5% of metastases occurred around the SMV and SMA at the root of the middle colic artery (MCA), respectively; 6.7% and 6.7% at the root of the right colic artery. In caecal cancer, 1.9% of metastases occurred around the SMV and 1.9% around the SMA. In ascending colon cancer, the rate was 1.1% around the SMV. Of the tumors, 17% fed mainly by the ileocolic artery had node metastases along the middle or right colic artery, as did 66.7% fed mainly by the right colic artery and 41.2% fed by the MCA (p = 0.01). Postoperative complications occurred in 42 patients (20.2%). Routine prophylactic extended lymphadenectomy around the SMA might not be necessary in caecum and ascending colon cancer. Dissection around the SMA may be necessary in cases of transverse colon cancer or when the feeding artery is the MCA.

Preservation of left colic artery in laparoscopic colorectal operation: The benefit challenge

During laparoscopic resection for colorectal cancer, there is controversy regarding whether the left colic artery (LCA) should be preserved at its origin.To investigate the prognostic significance of preservation of the LCA in colorectal cancer surgery.Patients were divided into two groups. The high ligation (H-L) technique (refers to ligation performed 1 cm from the beginning of the inferior mesenteric artery) group consisted of 46 patients, and the low ligation (L-L) technique (refers to ligation performed below the initiation of the LCA) group consisted of 148 patients. Operative time, blood loss, lymph nodes with tumor invasion, postoperative complications and recovery time, recurrence rate, and 5-year survival rate were compared between the two groups.The average number of lymph nodes detected in postoperative pathological specimens was 17.4/person in the H-L group and 15.9/person in the L-L group. There were 20 patients (43%) with positive lymph nodes (lymph node metastasis) in the H-L group and 60 patients (41%) in the L-L group. No statistical differences were found between the groups. Complications occurred in 12 cases (26%) in the H-L group and in 26 cases (18%) in the L-L group. The incidences of postoperative anastomotic complications and functional urinary complications were significantly lower in the L-L group. The 5-year survival rates in H-L and L-L groups were 81.7% and 81.6%, respectively, and relapse-free survival rates were 74.3% and 77.1%, respectively. The two groups were similar statistically.Complete mesenteric resection combined with lymph node dissection around the inferior mesenteric artery root while preserving the LCA is a beneficial surgical approach during laparoscopic resection for colorectal cancer.

Drainage pattern of the splenic flexure vein and its accompanying arteries using three-dimensional computed tomography angiography: a single-centre study of 600 patients.

The splenic flexure has variable vascular anatomy, and the details of the venous forms are not known. In this study, we report the flow pattern of the splenic flexure vein (SFV) and the positional relationship between the SFV and arteries such as the accessory middle colic artery (AMCA). This was a single-centre study using preoperative enhanced CT colonography images of 600 colorectal surgery patients. CT images were reconstructed into 3D angiography. SFV was defined as a vein flowing centrally from the marginal vein of the splenic flexure visible on CT. AMCA was defined as the artery feeding the left side of the transverse colon, separate from the left branch of the middle colic artery. The SFV returned to the inferior mesenteric vein (IMV) in 494 cases (82.3%), the superior mesenteric vein in 51 cases (8.5%) and the splenic vein in seven cases (1.2%). The AMCA was present in 244 cases (40.7%). The AMCA branched from the superior mesenteric artery or its branches in 227 cases (93.0% of cases with existing AMCA). In the 552 cases in which the SFV returned to the IMV, superior mesenteric vein or splenic vein, the left colic artery was the most frequent artery accompanying the SFV (42.2%), followed by the AMCA (38.1%) and the left branch of the middle colic artery (14.3%). The most common flow pattern of the vein in the splenic flexure is from the SFV to IMV. The SFV is frequently accompanied by the left colic artery or AMCA.

Real-time semi-quantitative assessment of anastomotic blood perfusion in mini‑invasive rectal resections by Sidestream Dark Field (SDF) imaging technology: a prospective in vivo pilot study.

Anastomotic leakage (AL) is one of the severe complications after rectal surgery, and anastomotic ischemia is one of the main factors. This prospective in vivo pilot study aimed to evaluate the effectiveness of Sidestream Dark Field (SDF) imaging in quantitative assessment of anastomotic microcirculation and to analyze its correlation with AL. Thirty-three patients with rectal cancer who underwent laparoscopic low anterior resection from 2019 to 2020 were enrolled. Microcirculation was measured by SDF imaging at the descending colon, the mesocolon transection line (MTL), and 1cm and 2cm distal to the MTL. Anastomotic microcirculation was measured at the stapler anvil edge before anastomosis. Quantitative perfusion-related parameters were as follows: microcirculation flow index (MFI), perfused vessel density (PVD), proportion of perfused vessels (PPV), and total vessel density (TVD). All patients obtained stable microcirculation images. Functional microcirculation parameters (MFI, PPV, PVD) decreased successively from the descending colon, the colon at MTL, and 1cm and 2cm distal to the MTL (all P < 0.01). Extremely poor microcirculation was found at the intestinal segment 2cm distal to the MTL. Micro-perfusion was significantly lower at the colonic limb of the anastomosis compared with the descending colon (all P < 0.001). Anastomotic leakage occurred in 3 patients (9.1%) whose anastomotic microcirculation was significantly lower than those without AL (all P < 0.01). Blood perfusion at the colonic limb of the anastomosis was significantly higher in patients with left colic artery preservation than in controls. SDF imaging is a promising technique for evaluating anastomotic microcirculation and has potential clinical significance for risk stratification of AL.

Efficacy of left colic artery preservation with D3 lymph node dissection in laparoscopic surgery for advanced sigmoid and rectal cancer.

For advanced left colon cancer, lymph node dissection at the root of the inferior mesenteric artery is recommended. Whether the left colic artery (LCA) should be preserved or resected remains contentious. The 367 patients who underwent laparoscopic sigmoidectomy or anterior resection and who were pathologically node-positive were reviewed. Patients were divided into LCA-preserving group (LCA-P, n = 60) and LCA-non-preserving group (LCA-NP, n = 307). Propensity score matching was applied to minimize selection bias and 59 patients were matched. Before matching, the rates of poor performance status and cardiovascular disease were higher in the LCA-P group (p < 0.001). After matching, operation time was longer (276 vs. 240min, p = 0.001), the frequency of splenic flexure mobilization (62.7% vs. 33.9%, p = 0.003) and lymphovascular invasion (84.7% vs. 55.9%, p = 0.001) was higher in the LCA-P group. Severe postoperative complications (CD ≥ 3) occurred only in the LCA-NP group (0% vs. 8.4%, p = 0.028). The median follow-up period was 38.5months (range 2.0-70.0months). The 5-year RFS rates (67.8% vs. 66.0%, p = 0.871) and OS rates (80.4% vs. 74.9%, p = 0.308) were comparable between the groups. Laparoscopic LCA-sparing surgery for left-sided colorectal cancer reduces the risk of severe complications and offers a favorable long-term prognosis.