Organ-preserving strategies have gained increasing relevance in the management of rectal cancer, driven by the improved ability of neoadjuvant therapies to induce major and complete tumor regression. The introduction of Total Neoadjuvant Therapy (TNT), delivered through induction and/or consolidation chemotherapy combined with radiotherapy, has substantially increased both pathological and clinical complete response rates. This progress has renewed interest in non-operative management—namely Watch-and-Wait (W&W)—and in local excision (LE) as potential alternatives to total mesorectal excision (TME). However, the W&W strategy raises important oncologic concerns, including a non-negligible rate of local regrowth—consistently reported at approximately 20–30%—which is associated with inferior distant metastasis-free survival and overall survival. These limitations underscore the inherent uncertainty in reliably defining a true clinical complete response. Within this context, LE may serve as a valuable diagnostic and therapeutic modality by confirming the pathological response, improving local control through removal of residual resistant tumor clones, and enabling more accurate stratification of patients suitable for organ preservation versus those requiring completion TME. Overall, while TNT has expanded the therapeutic opportunities for rectal preservation, LE appears to play a critical role in reducing the discordance between clinical and pathological assessment, thereby offering a more oncologically secure pathway toward organ preservation. This narrative review discusses the current role, benefits, and limitations of organ-preserving approaches after TNT in both locally advanced and early rectal cancer.

Background: Surgery for rectal cancer has evolved, with the adoption of minimally invasive and robotic techniques. This study evaluates whether robotic surgery for rectal cancer produces an improvement in perioperative and oncological outcomes compared with open and laparoscopic surgery in a retrospective analysis. Methods: A single-center retrospective study included 212 patients with histologically confirmed rectal cancer treated between 2012 and 2021. The patients were grouped by surgical approach: robotic (RR, n = 62), laparoscopic (LR, n = 68), and open resection (OR, n = 82). The primary endpoints were total mesorectal excision (TME) quality, operative time, and hospital stay. The secondary endpoints included the lymph node yield, the conversion rate, and the 5-year survival outcomes (OS and DFS), analyzed via Kaplan–Meier curves and proportional hazards models. Results: The TME quality was high across the groups (RR: 91.9%, LR: 86.8%, OR: 95.1%). The median operative time was the longest in the RR group (304 min vs. 221–222 min in LR/OR). Robotic surgery resulted in shorter median hospital stays (10 (RR) vs. 14 (LR) vs. 14 (OR) days) and a lower conversion rate (3.2% vs. 14.7% in LR). The lymph node yield was highest in the LR group (27.9), followed by the RR (25.5) and OR (23.0) groups. Postoperative pneumonia was most common in the OR group (12.2%), and bladder dysfunction occurred only in the OR group (4.9%). The five-year OS and DFS did not differ notably between the groups. Conclusions: Robotic surgery offers advantages in short-term outcomes, including fewer complications, shorter hospitalization, and lower conversion rates, despite longer operative times. Its oncological efficacy is equal compared to those of laparoscopic and open surgery.

The number of deaths from colorectal cancer in Japan continues to rise, with over 50,000 deaths recorded in 2018. In the 2024 edition, revisions to all aspects of treatment were undertaken, with corrections and additions made based on knowledge gained since the 2022 version (drug therapy) and the 2019 version (other treatments). The Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2024 for the treatment of colorectal cancer have been prepared to present standard treatment strategies, reduce disparities among institutions, avoid both unnecessary and insufficient treatment, and enhance mutual understanding between healthcare professionals and patients by making these guidelines accessible to the public. These guidelines were developed through consensus by the JSCCR Guideline Committee, following a careful review of evidence retrieved from literature searches and considering the medical insurance system and actual clinical practice in Japan. Therefore, these guidelines serve as a tool for managing colorectal cancer in real-world clinical settings. More specifically, they can be used to support obtaining informed consent from patients and selecting the most appropriate treatment method for each patient. Controversial topics were selected as clinical questions, and recommendations were provided. Each recommendation is accompanied by an evidence classification and a recommendation category, both based on consensus reached by the Guideline Committee members. This article presents the English version of the JSCCR guidelines 2024.

While the treatment of rectal cancer is multimodal, above all, a proper oncological resection is critical. The surgical management of rectal cancer has substantially evolved over the past 100 years, and continues to progress as we seek the best treatment. Rectal cancer was historically an unsurvivable disease, with poor understanding of the embryological planes, lymphatic drainage, and lack of standardized technique. Major improvements in recurrence, survival, and quality of life have resulted from advances in preoperative staging, pathologic assessment, the development and timing of multimodal therapies, and surgical technique. The most significant contribution in advancing rectal cancer care may be the standardization and widespread implementation of total mesorectal excision (TME). The TME, popularized by Professor Heald in the early 1980s as a sharp, meticulous dissection of the tumor and mesorectum with all associated lymph nodes through the avascular embryologic plane, has shown universal reproducible reductions in local recurrence and improvement in disease-free and overall survival. Widespread education and training of surgeons worldwide in the TME have significantly impact outcomes for rectal cancer surgery, and the procedure has become the gold standard for curative resection of rectal cancer. In this article, we discuss the evolution of the standard abdominal approach to the TME, with emphasis on the history, relevant anatomy, standard procedure steps, oncologic outcomes, and technical evolution.

This selection from the NCCN Guidelines for Rectal Cancer focuses on management of malignant polyps and resectable nonmetastatic rectal cancer because important updates have been made to these guidelines. These recent updates include redrawing the algorithms for stage II and III disease to reflect new data supporting the increasingly prominent role of total neoadjuvant therapy, expanded recommendations for short-course radiation therapy techniques, and new recommendations for a “watch-and-wait” nonoperative management technique for patients with cancer that shows a complete response to neoadjuvant therapy. The complete version of the NCCN Guidelines for Rectal Cancer, available online at NCCN.org, covers additional topics including risk assessment, pathology and staging, management of metastatic disease, posttreatment surveillance, treatment of recurrent disease, and survivorship.

The spread of cancer cells from primary tumors to regional lymph nodes is often associated with reduced survival. One prevailing model to explain this association posits that fatal, distant metastases are seeded by lymph node metastases. This view provides a mechanistic basis for the TNM staging system and is the rationale for surgical resection of tumor-draining lymph nodes. Here we examine the evolutionary relationship between primary tumor, lymph node, and distant metastases in human colorectal cancer. Studying 213 archival biopsy samples from 17 patients, we used somatic variants in hypermutable DNA regions to reconstruct high-confidence phylogenetic trees. We found that in 65% of cases, lymphatic and distant metastases arose from independent subclones in the primary tumor, whereas in 35% of cases they shared common subclonal origin. Therefore, two different lineage relationships between lymphatic and distant metastases exist in colorectal cancer.Copyright © 2017, American Association for the Advancement of Science.

Lymph node involvement is the most important prognostic factor when staging patients with colorectal cancer. The probability of detecting metastasis grows with the number of nodes examined. However, the number of nodes found in surgical specimens varies substantially. We have therefore determined the number and distribution of lymph nodes in the mesorectum by cadaveric dissection.Twenty formalin-fixed cadaveric pelvises were dissected (13 males). The search for lymph nodes was performed in a systematic way, from the division of the superior rectal artery following the smallest visible branches to the level of the anorectal ring.A total of 168 lymph nodes were found in 20 mesorectal blocks, with a mean (standard deviation) number per specimen of 8.4 (4.45). Lymph node size ranged from 2 to 10 mm. Distribution of lymph nodes in mesorectum was as follows: 120 nodes (71.4 percent) were found around the branches of the superior rectal artery proximal to the peritoneal reflection, and 48 nodes (28.6 percent) were found distal to the peritoneal reflection. Fourteen specimens (70 percent) had lymph nodes at the division of the superior rectal artery.The mean number of lymph nodes found in the mesorectum distal to the superior rectal artery division was 8.4. Most of these lymph nodes were proximal to the peritoneal reflection. The range found in the number of lymph nodes per case should be considered for use in the formulation of guidelines in anatomicopathologic studies of surgical specimens obtained after mesorectal excision.

Pelvic surgery carries an inherent risk of autonomic nerve injury leading to genitourinary and bowel dysfunction due to the close proximity of the superior hypogastric plexus (SHP). The aim of this study was to define the detailed anatomy of SHP and identify its relationship with the vascular landmarks and ureters for pelvic autonomic nerve-preserving surgery.A cadaveric study on the detailed anatomy of the SHP was conducted in our surgical anatomy research unit. Between 02/2019 and 10/2019, macroscopic anatomical dissections were performed on 45 fresh adult cadavers (39 male, 6 female). Distances between the SHP, major vascular structures, and other anatomical landmarks were measured.Three types of SHP morphology were observed: mesh (64.8%), single nerve (24.4%), and fiber (10.8%). SHP bifurcation was located inferior to the aortic bifurcation in all cases; however, it was observed cranial to the promontory in 80% of the cases, whereas 18% were caudally and 2% were over the promontory. The closest vessels to the left and right of the SHP bifurcation were the left common iliac vein (LCIV) (86.2%, the mean distance was 8.49 ± 7.97 mm) and the right internal iliac artery (RIIA) (48.2%, mean distance was 13.4 ± 9.79 mm), respectively. At SHP bifurcation level, the lateral edge of the SHP was detected on the LCIV in 22 cases and on the RIIA in 10 cases for the left and right side of the plexus, respectively. The distance between the SHP bifurcation and the ureter was 27.9 mm on the right and 24.2 mm on the left. The width of the left (LHN) and right hypogastric nerves (RHN) were 4.35 mm and 4.62 mm at 2 cm below the SHP bifurcation, respectively. LHN was on the vascular structures in 13 cases, whereas RHN in only 1 case, 2 cm below the SHP bifurcation.Understanding the location of the SHP, including its relationship with important anatomical landmarks, might prevent iatrogenic injury and reduce postoperative morbidity in the pelvic surgery setting.© 2022. Springer Nature Switzerland AG.

This evidence-based systematic review with meta-analysis aims to synthesize the inferior mesenteric artery (IMA) variants including their origin level, branching patterns, and morphometric characteristics.The study adhered to the latest guidelines. Four online databases were used for the systematic review, and studies that reported the prevalence of IMA variants were considered eligible for inclusion. A statistical meta-analysis was conducted using R programming software with a random-effects model to calculate the pooled prevalence of the variants.Twenty-three (23) studies were included in this analysis. The IMA typically originated at the 3rd lumbar vertebra (L3) level, occurring in 70.16% of cases. The most common branching pattern of the IMA was bifurcated, indicating a pooled prevalence of 63.89%. This predominant pattern involved the IMA bifurcating into the left colic artery (LCA) and a common trunk for both the superior rectal artery (SRA) and the sigmoid artery (SA), with a pooled prevalence of 46.09%. The IMA trifurcation and tetrafurcation had pooled prevalences of 27.35% and 11.62%, respectively. The diameter of the IMA had a pooled mean of 41.41 mm, and the distance from the IMA's origin to the LCA had a pooled mean of 40.67 mm.This review of existing literature delineates the IMA levels of origin, branching patterns, and morphometric characteristics. A comprehensive understanding of the surgical anatomy of this vessel is imperative during colorectal cancer procedures. Consequently, surgeons operating in this anatomical region must possess an in-depth knowledge of typical and variant anatomical structures.© 2025. The Author(s).

We aimed to investigate manual subtraction computed tomography angiography (MS-CTA) to further confirm the distribution and classification of LCA (left colic artery) ascending/descending branches, then observe the postoperative blood flow path to illustrate how the above branches evolved to postoperative blood path.89 patients with distal sigmoid and rectal cancer were referred in our observation and underwent MS-CTA between June 2020 and March 2022. We classified the distribution of LCA and confirmed whether there exists AMCA (accessory middle colic artery). Then we planned blood flow path based on the classification of LCA branches before operation. High ligation was applied in regular radical surgery. During operation, we carefully protect the bifurcation of ascending and descending LCA. Then we compared the planned blood flow path with the actual postoperative blood flow path to verify the mechanism we proposed previously.Of 89 patients, 82 cases met our criteria, we summarized 6 distribution pattens of LCA ascending and descending branches. These preoperative pattens are consistent with the inspection during operation. The postoperative blood flow path of 6 pattens is evolved from the above adjacent anastomotic branches and is consistent with the planned blood flow path. We also found 2 cases with IMA stenosis and 1 case with SMA stenosis under pathological condition, and their compensatory blood flow path is in accordance with our theory. The rate of the anastomotic leakage in our study group is relatively low (7.3%).MS-CTA could confirm the distribution of LCA and AMCA, display accurate postoperative blood reconstruction path after IMA high ligation, and it further verified the mechanism we proposed previously, which is the proximal anastomotic branches forming new blood flow path from high-pressure area to the low-pressure area. This mechanism might be helpful for performing accurate laparoscopic sigmoid and rectal cancer surgery.Copyright © 2023. Published by Elsevier Ltd.

Intraoperative damage of pelvic autonomic nerves is the primary reason for postoperative sexual and urinary dysfunction after rectal cancer surgery,1,2 especially in patients with low rectal cancer. In the present study, we developed the nerve plane as a novel concept in rectal cancer surgery, which served as a landmark for better preservation of pelvic autonomic nerves in standardized total mesorectal excision (TME) surgery. The nerves never exist alone, and are always surrounded by tiny capillaries and adipose tissue, which are covered by a thin layer of membranous tissue, leading to a continuous plane, which we defined as the nerve plane. The nerve plane could be preserved from thermal damage, ischemic injury, nerve stretching, and chemical factors produced by local inflammatory effects. We also found loose connective tissue (the first gap) between the proper fascial of the rectum and the nerve plane, which was also a natural avascular holy's plane. Using the concept of nerve plane, the proposed functional TME procedure could help surgeons to better protect pelvic autonomic nerves from injury. Herein, we present a brief video to describe the technical aspects of a laparoscopic functional TME in rectal cancer surgery.Fifty-eight consecutive male patients without preoperative sexual and urinary dysfunction underwent laparoscopic functional TME surgery for histologically confirmed adenocarcinoma at our hospital since 2018. The present study was approved by the institutional review board of the Renmin Hospital of Wuhan University (2018-X-08), and written informed consent was obtained from all patients. Urinary and sexual function was evaluated using the international prostatic symptom score (IPSS)3 and the 5-item version of International Index of Erectile Function (IIEF-5)4 questionnaires, respectively, which are internationally recognized as well-structured and reliable questionnaires to evaluate urinary and sexual function. Moderate-to-severe urinary dysfunction was defined as IPSS score >8 points,2 while erectile dysfunction was defined as IIEF-5 score ≤ 11points.5 The laparoscopic functional TME procedure shown in the video is described as follows. First, the incision line was marked on the peritoneum from the lower edge of the duodenum to the pelvic entrance with an electric hook using a medium approach. The holy's plane was divided into five structures by enforcing traction and anti-traction, which included fascia propria of the rectum, the loose areolar connective tissue over the nerve plane (the first gap), the nerve plane, the loose areolar connective tissue below the nerve plane (the second gap), and the Gerota's fascia or the presacral fascia. Second, dissection over the nerve plane was performed from the lower edge of the duodenum to the pelvic entrance. Superior hypogastric plexus nerve plane, abdominal aortic plexus nerve plane, and inferior mesenteric plexus nerve plane were clearly displayed. Dissection was continued in this way, and the left and right hypogastric nerve planes were also preserved. Finally, the pelvic cavity was entered, and posterior dissection was continued downward to the Waldeyer fascia. We selected to go over the Waldeyer fascia along the nerve plane instead of transecting it to enter the superior levator space, thereby some small nerves such as efferent branches of hypogastric nerves in this area were protected from injury. The lateral pelvic dissection was continued over the pelvic plexus nerve plane, anterior pelvic dissection was continued, and the Denonvillier's interfascial space was entered between the anterior layer and the posterior layer of Denonvilliers' fascia. The left and right neurovascular bundles (NVB) were avoided and not intentionally exposed during the operation, thereby protecting them from injury. Although some steps of the procedure are displayed very close to the anatomical landmarks, patience and higher-resolution laparoscopic equipment are needed for surgeons to find the nerve plane. For less experienced surgeons, we suggest that the harmonic with the "hot" blade should be as far away from the nerves as possible during the radical resection of tumor. After the rectum was dissected, superior hypogastric plexus nerve plane, abdominal aortic plexus nerve plane, inferior mesenteric plexus nerve plane, hypogastric nerve plane, pelvic plexus nerve plane, left ureter, and genital vessels were displayed and completely preserved. The intraoperative nerve plane and mesorectum of the postoperative specimen were intact and smooth.The median age of patients was 53 years, with a body mass index (BMI) of 24.0 kg/m. The median total operation time was 198 min (range 128-248 min). The median volume of blood loss was 30 ml (range 10-50 ml). The median number of retrieved lymph nodes was 31 (range 13-65). No patient showed postoperative moderate-to-severe urinary dysfunction at 6 months. The incidence of postoperative erectile dysfunction was 5.17% (3/58) at 12 months. No patient was lost during 1-year of follow-up.Nerve plane is an optimal surgical landmark for laparoscopic functional total mesorectal excision in rectal cancer. It provides a superior surgical technique for pelvic autonomic nerve protection.

The aim of this clinical trial is to evaluate the influence of high and low ligation of the inferior mesenteric artery with apical lymph node dissection on the anastomotic blood supply, lymph node retrieval rate, operative time and anastomotic leakage rate in rectal cancer surgery.

There is no demonstrated benefit of high-tie versus low-tie vascular transections in low rectal cancer surgery. The aim of this study was to compare the effects of high tie and low tie of the inferior mesenteric artery on colonic length.This study was conducted in a surgical anatomy research laboratory. Anatomical dissections were performed on 11 human cadavers. We performed full left colonic mobilization, section of the descending-sigmoid junction, and high and low ligation of the inferior mesenteric artery. Distance from the proximal colon limb to the lower edge of the pubis symphysis was recorded after each step of vascular division. Three measurements were successively performed: before vascular section, after inferior mesenteric artery ligation, and after inferior mesenteric artery and vein section.Before vascular section, the mean distance between colonic end and lower edge of the symphysis pubis was - 1.9 ± 3.5 cm. After combined artery and vein section, the mean distance was + 10.7 ± 4.6 cm for high tie and + 1.5 ± 3 cm for low tie. A limitation of this study is the use of embalmed anatomical specimens, rather than live patients, and the small number of specimens. This study also does not evaluate colon limb vascularization or the impact of proximal lymph node dissection on survival rates.High tie of the inferior mesenteric artery at its aortic origin allows a gain of extra length of about 9 cm over low tie.

The aim of the present study was to compare the incidence of genitourinary (GU) dysfunction after elective laparoscopic low anterior rectal resection and total mesorectal excision (LAR + TME) with high or low ligation (LL) of the inferior mesenteric artery (IMA). Secondary aims included the incidence of anastomotic leakage and oncological outcomes.The criterion standard surgical approach for rectal cancer is LAR + TME. The level of artery ligation remains an issue related to functional outcome, anastomotic leak rate, and oncological adequacy. Retrospective studies failed to provide strong evidence in favor of one particular vascular approach and the specific impact on GU function is poorly understood.Between June 2014 and December 2016, patients who underwent elective laparoscopic LAR + TME in 6 Italian nonacademic hospitals were randomized to high ligation (HL) or LL of IMA after meeting the inclusion criteria. GU function was evaluated using a standardized survey and uroflowmetric examination. The trial was registered under the ClinicalTrials.gov Identifier NCT02153801.A total of 214 patients were randomized to HL (n = 111) or LL (n = 103). GU function was impaired in both groups after surgery. LL group reported better continence and less obstructive urinary symptoms and improved quality of life at 9 months postoperative. Sexual function was better in the LL group compared to HL group at 9 months. Urinated volume, maximum urinary flow, and flow time were significantly (P < 0.05) in favor of the LL group at 1 and 9 months from surgery. The ultrasound measured post void residual volume and average urinary flow were significantly (P < 0.05) better in the LL group at 9 months postoperatively. Time of flow worsened in both groups at 9 months compared to baseline. There was no difference in anastomotic leak rate (8.1% HL vs 6.7% LL). There were no differences in terms of blood loss, surgical times, postoperative complications, and initial oncological outcomes between groups.LL of the IMA in LAR + TME results in better GU function preservation without affecting initial oncological outcomes. HL does not seem to increase the anastomotic leak rate.

Colorectal cancer is the second and third most prevalent gastrointestinal tract malignancy among women and men. Over the past few decades, the incidence and mortality of colorectal cancer has gradually increased in China. Many studies have indicated that the robotic surgery system addresses several limitations of laparoscopic surgery and is a safe and feasible surgical approach. However, preservation of the left colic artery (LCA) during robotic total mesorectal excision (R-TME), along with short-term surgical outcomes and complications, has always been the focus of surgeons. Therefore, the present study aimed to analyze the short-term surgical effects of LCA preservation and postoperative complications within 30 days in patients with and without LCA preservation during R-TME. In this retrospective cohort study, we collected and analyzed the clinical data of R-TME performed at the anorectal Department of Gansu Provincial Hospital between January 2018 and January 2023. (In our center, the robotic Da Vinci Xi surgical system is utilized for surgical procedures.) The patients were divided into 2 groups according to whether the LCA was preserved during total mesorectal excision. A total of 150 patients were included in this study; 69 patients underwent LCA preservation, and 81 underwent LCA non-preservation surgeries. In the LCA preservation group, the first postoperative ventilation time (3.2 ± 1.3 days vs 4.2 ± 1.8 days, P = .000) and the time of the first postoperative fluid diet (4.9 ± 1.1 days vs 5.1 ± 1.6 days, P = .001) were significantly improved, and the incidence of protective ileostomy (4.3% vs 14.8%, P = .033) was significantly reduced compared with that in the LCA non-preservation group (P &lt; .05). The overall complication rates within 30 days in the 2 groups were not significantly different. However, the incidence of anastomotic leakage in the LCA preservation group was significantly lower than that in the LCA non-preservation group (0.0% vs 7.4%, P = .021). R-TME is safe and feasible for the preservation of the LCA, and LCA preservation can promote gastrointestinal function recovery. In addition, LCA preservation ensures the extent of No. 253 lymph node dissection, significantly reduces the incidence of anastomotic leakage and ileal protective fistula and improves the patients’ quality of life.

We investigated how Japanese D3 dissection with left colic artery (LCA) preservation affects anastomotic leakage after anterior resection with anastomosis for rectal cancer, based on the leak rate. The correlation between LCA preservation, survival, and cancer recurrence after resection was also analyzed.

We investigated how Japanese D3 dissection with left colic artery (LCA) preservation affects anastomotic leakage after anterior resection with anastomosis for rectal cancer, based on the leak rate. The correlation between LCA preservation, survival, and cancer recurrence after resection was also analyzed.

To evaluate the feasibility of a 3D image processing and reconstruction system (3D-IPR) based on pelvic magnetic resonance imaging (MRI) for surgical planning of locally advanced rectal cancer (LARC) and recurrent pelvic rectal cancer (PRCR).Achieving R0 resection is critical for prognosis in LARC and PRCR, but 2D imaging often limits precise surgical planning in complex pelvic anatomy. 3D reconstruction may enhance visualization and decision-making.In this prospective feasibility multicenter study, 37 patients with LARC or PRCR and threatened circumferential resection margins on MRI underwent surgical planning using 3D-IPR. This tool provides information on tumor localization, infiltration volume, and precise spatial relationships with adjacent structures. Outcomes included surgeon satisfaction, changes in surgical approach, and perioperative results.A total of 56.7% of cases were primary rectal cancer and 43.2% were recurrent cancer. Satisfaction percentage of 3D-IPR to select the best surgical route was 100%. Minimally invasive techniques were employed in 40% of the surgeries. In 37.8% of cases, it was considered that the 3D-IPR changed the decision on the surgical attitude with respect to the neighboring organ with suspicion of infiltration. R0 resection was achieved in 75.7% of cases, with no perioperative mortality and a severe complication rate of 27%.A surgical planner based on 3D reconstruction using mathematical algorithms from pelvic MRI is feasible for performing tailored surgery for locally advanced rectal cancers and pelvic recurrence. Further research will show if this new tool reduces the morbidity and mortality rates, increasing the probability of R0 surgery, and increasing survival.Copyright © 2025 The Author(s). Published by Wolters Kluwer Health, Inc.