Circumferential Resection Margin Research Articles

The predicting value of post neoadjuvant treatment magnetic resonance imaging: a meta-analysis.

Neoadjuvant therapy has become standard of care for locally advanced rectal cancer patients. It is correlated with improved clinical and pathological outcomes, including significant tumor downstaging and organ preservation in certain patients. Magnetic resonance imaging (MRI), which has become the standard for pre-operative staging, is also used for clinical and pre-operative restaging following pre-operative treatment. In this meta-analysis, we aimed to evaluate the concordance between restaging MRI (following the completion of neoadjuvant therapy) and postoperative pathology result. We conducted a meta-analysis following the PRISMA 2020 guidelines. Two independent reviewers searched PubMed and Google Scholar for studies reporting restaging MRI results compared to pathological outcomes. Outcomes included tumor and nodal staging, circumferential resection margin (CRM) and pathological complete response (pCR). Out of 25,000 studies found on the initial search; 33 studies were included. The studies were published between 2005 and 2023 and included 4100 patients (57.14% males). The median age was 62.45 years. The median interval between the conclusion of neoadjuvant treatment and the subsequent restaging MRI was 6 weeks (range 4.14-8.8 weeks). The pooled concordance rates between the restaging MRI and the pathological outcomes for ypT stage and ypN stage were 63.9% (54.5%-73.3%, I2 = 96.02%) and 60.9% (42.9%-78.9%, I2 = 98.96%), respectively. The pooled concordance for predicting pathological complete response was 70.4% (53.6%-87.1%, I2 = 98.21%). As for the circumferential resection margin (CRM), the pooled concordance was 78.2.% (71.6%-84.8%, I2 = 83.76%). Our findings suggest that the concordance rates between restaging MRI and pathological outcomes in rectal cancer patients following neoadjuvant therapy are limited. Caregivers should take these results into consideration when making clinical decisions about these patients. More data should be gathered about the predictive value of MRI after total neoadjuvant therapy as well as immunotherapy in rectal cancer patients.

Time-dependent prognostic impact of circumferential resection margin in T3 thoracic esophageal squamous cell carcinoma.

Esophageal cancer presents a clinical challenge due to its high incidence and unfavorable prognosis. The prognostic role of the circumferential resection margin (CRM) remains highly controversial, potentially due to its temporal dynamics coupled with variability in follow-up durations across studies. We aimed to explore the time-dependent prognostic significance of CRM in T3 esophageal squamous cell carcinomas (ESCCs). We systematically reviewed literature from 1990 to 2023 to determine how follow-up duration influences the prognostic role of CRM in esophageal cancer. Concurrently, we performed a retrospective examination of 354 patients who underwent treatment at the National Cancer Center between 2015 and 2018. Integrating a time interaction term in the Cox regression analyses enabled us to not only identify independent risk factors affecting overall survival (OS) but also to specifically scrutinize the potential temporal variations in CRM's prognostic impact. Our literature review suggested that CRM's influence on prognosis diminishes with longer follow-up durations for both classifications, namely the Royal College of Pathologists (RCP) (β= -0.003, P< 0.001) and the College of American Pathologists (CAP) (β= -0.007, P< 0.001). Time-dependent multivariate Cox regression analysis emphasized the evolving nature of CRM's prognostic effect, and the inclusion of the time interaction term enhanced model accuracy. In conclusion, CRM is an independent prognostic factor for T3 thoracic ESCC patients. Its influence appears to decrease over extended follow-up periods, shedding light on the heterogeneity seen in previous studies. With the time interaction term, CRM becomes a more precise post-operative prognostic indicator for esophageal cancer.

The mode of circumferential margin involvement in rectal cancer determines its impact on outcomes: A population-based study

BackgroundThe clinical value of different modes of CRM involvement in rectal cancer patients is unclear. This study aims to determine the clinical impact of different modes of circumferential resection margin (CRM) involvement in patients with a locally advanced rectal carcinoma. Patients and methodsA cohort of patients who were diagnosed with stage III rectal cancer between June 2014 and June 2020 was selected from the prospective Dutch nationwide pathology databank (PALGA). Histopathological and clinical data were analyzed according to the nature of CRM involvement (via primary tumor invasion, lymph node metastasis, tumor deposit, multiple factors) and analyses on recurrence and overall survival (OS) were performed. Results3020 patients were included, of whom 12.4 % had a positive CRM. The majority of these patients (63.2 %) had CRM involvement by primary tumor invasion and in 9 % of patients multiple factors caused the positive CRM. The rates of local recurrence and distant metastasis were related to the nature of the CRM involvement, with lowest rate for lymph node metastasis and highest rate for multiple factors. On multivariate analysis, CRM involvement by primary tumor invasion, tumor deposits and multiple factors, but not by lymph node metastasis, were associated with poor OS. ConclusionThis nationwide population based study highlights the clinical importance of reporting the nature of CRM involvement in rectal cancer patients. Lymph node metastasis involving the CRM does not bear the same risks for local recurrence, distant metastases and OS as CRM involvement by primary tumor invasion or CRM involvement by multiple factors.

Comparative Outcomes of Robotic Versus Open Proctectomy for Rectal Cancer at High Risk of Positive Circumferential Resection Margin.

Concerns persist regarding the effectiveness of robotic proctectomy when compared with open proctectomy for locally advanced rectal cancer with a high risk of circumferential resection margin involvement. Comparison of surrogate cancer outcomes following robotic versus open proctectomy in this subpopulation. Retrospective cohort study. Three academic hospitals (Mayo Clinic Arizona, Florida, and Rochester) through the Mayo Data Explorer platform. Patients at high risk of circumferential resection margin involvement were selected based on the magnetic resonance imaging-based definition from Mercury I and II trials. Rate of pathologic circumferential resection margin involvement (≤1 mm), mesorectal grading, rate of distal margin involvement. Out of 413 patients, 125 (30%) underwent open and 288 (70%) robotic proctectomy. Open proctectomy was significantly associated with a greater proportion of cT4 tumors (39.3% vs. 24.8%, p = 0.021), multivisceral/concomitant resections (40.8% vs. 18.4%, p < 0.001) and less frequent total neoadjuvant therapy use (17.1% vs. 47.1%, p = 0.001). Robotic proctectomy was less commonly associated with pathologic circumferential resection margin involvement (7.3% vs. 17.6%, p = 0.002), including after adjustment for cT stage, neoadjuvant therapy, and multivisceral resection (OR 0.326, 95% CI, 0.157-0.670, p = 0.002). Propensity score-matching on 66 patients per group and related multivariable analysis no longer indicated any reduction of circumferential positive margin rate associated with robotic surgery (p = 0.86 and p = 0.18). Mesorectal grading was comparable (incomplete mesorectum in 6% RP patients vs. 11.8% OP patients, p = 0.327). All cases had negative distal resection margins. Retrospective design. In patients with locally advanced rectal cancer at high risk of circumferential resection margin involvement, robotic proctectomy is an effective approach and could be pursued when technically possible as an alternative to open proctectomy. See Video Abstract.

A comparison of whole-mount and conventional sections for pathological mesorectal extension and circumferential resection margin assessment after total mesorectal excision

IntroductionThe objective of the study is to compare 2 techniques for histological handling of rectal cancer specimens, namely whole-mount in a large block vs conventional sampling using small blocks, for mesorectal pathological assessment of circumferential resection margin status and depth of tumor invasion into the mesorectal fat. MethodsThis is a prospective study including 27 total mesorectal excision specimens of rectal cancer from patients treated for primary rectal carcinoma between 2020 and 2022 in a specialized multidisciplinary Colorectal Unit. For each total mesorectal excision specimen, 2 contiguous representative tumoral slices were selected and comparatively analyzed with whole-mount and small blocks macroscopic dissection techniques, enabling comparison between them in the same surgical specimen. The agreement between the 2 techniques to assess the distance of the tumor from the circumferential resection margin as well as the depth of tumor invasion was evaluated with the Student’s t-test for paired samples, Pearson’s correlation coefficient, and the Bland-Altman method comparison analysis. ResultsComplete mesorectal excision was observed in 8% of cases. Circumferential resection margin involvement was observed in only one case (4 %). The whole-mount and small block techniques obtained similar results when we assessed the distance to the circumferential resection margin (t-test P = 0.8, r = 0.92) and the depth of mesorectal infiltration (t-test P = 0.6, r = 0.95). ConclusionsBoth gross dissection techniques (whole-mount vs multiple small cassettes) are equivalent and reliable to assess the distance to circumferential resection margin and the depth of mesorectal infiltration in the mesorectal fat in rectal cancer staging.

Dissection layer selection based on an understanding of pelvic fascial anatomy in transanal total mesorectal excision.

This study aimed to review the historical transition of rectal cancer surgery and recent evidence regarding transanal total mesorectal excision (TaTME). Additionally, it outlined the anatomical landmarks and technical considerations essential for successful TaTME. Anatomical studies and surgical techniques were analyzed to identify key landmarks and procedural steps crucial for TaTME. TaTME offers improved visibility and maneuverability even in the deep and narrow pelvis and is expected to contribute to tumor radical cure rates. By securing the circumferential resection margin and distal margin while preserving pelvic autonomic nerve function, TaTME holds promise for maintaining postoperative urinary and sexual functions. Key anatomical landmarks include the endopelvic fascia posteriorly, the S4-pelvic splanchnic nerve laterally, and the prostate or posterior vaginal wall anteriorly. Selecting the appropriate dissection layer based on tumor depth and ensuring precise incision of the tendinous arch of the pelvic fascia contributes to successful TaTME outcomes. TaTME represents a significant advancement in rectal cancer surgery, offering improved outcomes through meticulous attention to anatomical detail and precise dissection techniques. Understanding the historical context of rectal cancer surgery alongside recent evidence on TaTME is essential for optimizing patient outcomes and expanding the safe implementation of this innovative approach.

Essential knowledge and technical tips for total mesorectal excision and related procedures for rectal cancer.

Total mesorectal excision (TME) has greatly improved rectal cancer surgery outcomes by reducing local recurrence and enhancing patient survival. This review outlines essential knowledge and techniques for performing TME. TME emphasizes the complete resection of the mesorectum along embryologic planes to minimize recurrence. Key anatomical insights include understanding the rectal proper fascia, Denonvilliers fascia, rectosacral fascia, and the pelvic autonomic nerves. Technical tips cover a step-by-step approach to pelvic dissection, the Gate approach, and tailored excision of Denonvilliers fascia, focusing on preserving pelvic autonomic nerves and ensuring negative circumferential resection margins. In Korea, TME has led to significant improvements in local recurrence rates and survival with well-adopted multidisciplinary approaches. Surgical techniques of TME have been optimized and standardized over several decades in Korea, and minimally invasive surgery for TME has been rapidly and successfully adopted. The review emphasizes the need for continuous research on tumor biology and precise surgical techniques to further improve rectal cancer management. The ultimate goal of TME is to achieve curative resection and function preservation, thereby enhancing the patient's quality of life. Accurate TME, multidisciplinary-based neoadjuvant therapy, refined sphincter-preserving techniques, and ongoing tumor research are essential for optimal treatment outcomes.

Anatomic Basis of Rectal Cancer Staging: Clarifying Controversies and Misconceptions.

Rectal MRI provides a detailed depiction of pelvic anatomy; specifically, the relationship of the tumor to key anatomic structures, including the mesorectal fascia, anterior peritoneal reflection, and sphincter complex. However, anatomic inconsistencies, pitfalls, and confusion exist, which can have a strong impact on interpretation and treatment. These areas of confusion include the definition of the rectum itself, specifically differentiation of the rectum from the anal canal and the sigmoid colon, and delineation of the high versus low rectum. Other areas of confusion include the relative locations of the mesorectal fascia and peritoneum and their significance in staging and treatment, the difference between the mesorectal fascia and circumferential resection margin, involvement of the sphincter complex, and evaluation of lateral pelvic lymph nodes. The impact of these anatomic inconsistencies and sources of confusion is significant, given the importance of MRI in depicting the anatomic relationship of the tumor to critical pelvic structures, to triage surgical resection and neoadjuvant chemoradiotherapy with the goal of minimizing local recurrence. Evolving treatment paradigms also place MRI central in management of rectal cancer. ©RSNA, 2024.

Temporal Trends in Survival Outcomes for Patients with Esophageal Cancer Following Neoadjuvant Chemoradiotherapy: A 14-Year Analysis.

The prognosis for patients with esophageal cancer who received neoadjuvant chemoradiotherapy (nCRT) followed by surgery has shown improvement in recent years. We sought to identify the critical factors contributing to enhanced survival outcomes. We retrospectively examined 427 patients with esophageal cancer treated with nCRT and esophagectomy across two periods: P1 (from 1 January 2004 to 31 December 2011) and P2 (from 1 January 2012 to 31 December 2017). The introduction of the CROSS regimen and total meso-esophagectomy in P2 prompted an evaluation of their effects on perioperative outcomes and overall survival (OS). During P2, the occurrence of recurrent laryngeal nerve palsy increased significantly from 3.9 to 16.8% (p < 0.001), while pneumonia and in-hospital mortality rates remained unchanged. The median OS improved from 19.2 to 29.2 months (p < 0.001) between P1 and P2. Multivariable analysis identified higher nodal yields and the achievement of major response as favorable prognostic factors. Conversely, an involved circumferential resection margin (CRM), an advanced ypN stage, and pneumonia were independently associated with poor outcomes. Patients treated during P2 had a lower prevalence of involved CRM (10% vs. 25.1%, p < 0.001), a higher rate of major response (52.7% vs. 34.8%, p < 0.01), and a greater nodal yield (27.8 vs. 10.9, p < 0.001). The clinical outcomes following nCRT and surgery have improved significantly over time. This progress can be attributed to multiple factors, with the primary drivers being the refinement of nCRT protocols and the application of radical surgery.

Comparison of conventional MRI analysis versus MRI-based radiomics to predict the circumferential margin resection involvement of rectal cancer

BackgroundTo compare the application of conventional MRI analysis and MRI-based radiomics to identify the circumferential resection margin (CRM) status of rectal cancer (RC).MethodsA cohort of 301 RC patients with 66 CRM invloved status and 235 CRM non-involved status were enrolled in this retrospective study between September 2017 and August 2022. Conventional MRI characteristics included gender, age, diameter, distance to anus, MRI-based T/N phase, CEA, and CA 19 − 9, then the relevant logistic model (Logistic-cMRI) was built. MRI-based radiomics of rectal cancer and mesorectal fascia were calculated after volume of interest segmentation, and the logistic model of rectal cancer radiomics (Logistic-rcRadio) and mesorectal fascia radiomics (Logistic-mfRadio) were constructed. And the combined nomogram (nomo-cMRI/rcRadio/mfRadio) containing conventional MRI characteristics, radiomics of rectal cancer and mesorectal fascia was developed. The receiver operator characteristic curve (ROC) was delineated and the area under curve (AUC) was calculated the efficiency of models.ResultsThe AUC of Logistic-cMRI was 0.864 (95%CI, 0.820 to 0.901). The AUC of Logistic-rcRadio was 0.883 (95%CI, 0.832 to 0.928) in the training set and 0.725 (95%CI, 0.616 to 0.826) in the testing set. The AUCs of Logistic-mfRadio was 0.891 (95%CI, 0.838 to 0.936) in the training set and 0.820 (95%CI, 0.725 to 0.905) in the testing set. The AUCs of nomo-cMRI/rcRadio/mfRadio were the highest in both the training set of 0.942 (95%CI, 0.901 to 0.969) and the testing set of 0.909 (95%CI, 0.830 to 0.959).ConclusionMRI-based radiomics of rectal cancer and mesorectal fascia showed similar efficacy in predicting the CRM status of RC. The combined nomogram performed better in assessment.

Clinicopathological significance and prognostic analysis of p21 and EGFR in colorectal cancer: a retrospective analysis on 12 319 cases in China

AimsColorectal cancer (CRC) is the third most common malignancy worldwide. Accurate pathological diagnosis and predictive abilities for treatment response and prognosis are crucial for patients with CRC. This study aims...

Clinical outcomes of neoadjuvant chemoradiotherapy followed by total mesorectal excision in locally advanced rectal cancer with mesorectal fascia involvement.

For the treatment of locally advanced rectal cancer (LARC), research on primary lesions with mesorectal fascia (MRF) involvement is lacking. This study analyzed the clinical outcomes and efficacy of dose-escalated neoadjuvant concurrent chemoradiotherapy (NCRT) to patients with LARC involving MRF. We retrospectively reviewed 301 patients who were diagnosed with LARC involving MRF and underwent NCRT followed by total mesorectal excision (TME). Patients who received radiotherapy (RT) doses of ≤50.4 Gy were defined as the non-boost group, while ≥54.0 Gy as the boost group. Pathological tumor response and survival outcomes, including intrapelvic recurrence-free survival (IPRFS), distant metastases-free survival (DMFS) and overall survival (OS), were analyzed. A total of 269 patients (89.4%) achieved a negative pathological circumferential resection margin and 104 (34.6%) had good pathological tumor regression grades. With a median follow-up of 32.4 months, IPRFS, DMFS, and OS rates at 5-years were 88.6%, 78.0%, and 91.2%, respectively. In the subgroup analysis by RT dose, the boost group included more advanced clinical stages of patients. For the non-boost group and boost group, 5-year IPRFS rates were 90.3% and 87.0% (p = 0.242), 5-year DMFS rates were 82.0% and 71.3% (p = 0.105), and 5-year OS rates were 93.0% and 80.6% (p = 0.439), respectively. Treatment related toxicity was comparable between the two groups (p = 0.211). Although this retrospective study failed to confirm the efficacy of dose-escalated NCRT, favorable IPRFS and pathological complete response was achieved with NCRT followed by TME. Further studies combining patient customized RT dose with systemic therapies are needed.

Risk Factors for Recurrence After Surgery for Rectal Cancer in a Modern, Nationwide Population-Based Cohort

BackgroundThe success of modern multimodal treatment in rectal cancer is dependent on risk prediction. Better knowledge of the risk of locoregional and distant recurrence, in relation to preoperative treatment, pathological stage, and commonly used risk factors, is needed when deciding on adjuvant therapy and surveillance.MethodsThe Swedish ColoRectal Cancer Registry was used to identify patients diagnosed with rectal adenocarcinoma between 2011 and 2018. Readily available variables, including patient, tumor, and treatment factors were exposures. Cox proportional hazard models were used to identify important risk factors for recurrence and calculate recurrence risks.ResultsA total of 9428 curatively resected patients were included and followed for a median of 72 months. Eighteen percent had distal recurrence and 3% had locoregional recurrence at 5 years. Risk factors with major impact on distal recurrence were pT4a (hazard ratio [HR] 5.1, 95% confidence interval [CI] 3.3–8.0), pN2b (HR 3.4, 95% CI 2.7–4.2), tumor deposit (HR 1.7, 95% CI 1.5–1.9), lymph node yield (HR 1.5, 95% CI 1.3–1.8), and tumor level 0–5 cm (HR 1.5, 95% CI 1.3–1.8). Pathologic stage and number of risk factors identified groups with markedly different recurrence risks in all neoadjuvant treatment groups.ConclusionsReadily available risk factors, as a complement to stage, are still valid and robust in all neoadjuvant treatment groups. Tumor deposit is important, while circumferential resection margin might no longer be important with improved oncological treatments and high-quality TME surgery. Tailored surveillance is possible in selected groups using risk stratification based on stage and risk factors.

Tailoring rectal cancer surgery: Surgical approaches and anatomical insights during deep pelvic dissection for optimal outcomes in low-lying rectal cancer.

This review article explores advanced surgical approaches and anatomical insights for tailoring rectal cancer surgery, particularly focusing on low-lying rectal cancer. With the evolution of imaging technologies, precise preoperative planning has become possible, enhancing the visualization of anatomy surrounding the rectum and enabling more accurate assessments of circumferential resection margin (CRM) involvement. The article emphasizes the dynamic nature of rectal cancer treatment, advocating for individualized surgical planning based on comprehensive preoperative imaging and intraoperative assessment. This approach aims to optimize patient care by integrating recent advancements and anatomical insights into clinical practice for the management of low-lying rectal cancer. Particularly, the article discusses the importance of customizing the excision of Denonvilliers' fascia (DVF) based on tumor characteristics for optimal oncologic and functional outcomes, especially for anteriorly located tumors. It highlights the need for precise dissection techniques to ensure a negative CRM while preserving critical anatomical structures. Additionally, the review addresses the surgical management of tumors at the anorectal ring and introduces the Gate Approach for deep anterolateral pelvic dissection. Special attention is given to tumors impacting the membranous and prostate urethra, emphasizing tailored surgical approaches to balance complete tumor resection with the preservation of urogenital functions.

Robotic versus laparoscopic surgery for middle and low rectal cancer (REAL): Primary outcome of a multicenter randomized controlled trial.

3617 Background: Robotic surgery for rectal cancer is gaining popularity, but persuasive evidence on long-term oncological outcomes is lacking. This multicenter randomized controlled trial compared robotic and conventional laparoscopic surgery regarding surgical quality and long-term oncological outcomes among patients with middle and low rectal cancer. Previously the short-term outcomes of this trial had been reported that robotic surgery had significantly lower circumferential resection margin positivity rate, lower postoperative complication rate, and better postoperative recovery. Now the long-term oncological outcomes were reported. Methods: This superiority trial was undertaken at 11 hospitals in 8 Chinese provinces. Patients with middle (&gt; 5–10 cm from anal verge) or low (0–5 cm from anal verge) rectal adenocarcinoma, cT1–T3 N0–1 or ycT1–T3 Nx after preoperative radio-/chemoradiotherapy, and no evidence of distant metastasis were enrolled and randomly assigned in a 1:1 ratio to receive robotic or conventional laparoscopic surgery. The 3-year locoregional recurrence rate was the primary outcome and was compared using modified intention-to-treat (mITT) analysis. Secondary outcomes included disease-free survival and overall survival. All time-to-event outcomes were calculated using Kaplan-Meier method with log-rank test. This trial was registered with ClinicalTrials.gov (NCT02817126). Results: Between July 2016 and December 2020, 1240 patients were enrolled, and 1171 were included in the mITT analysis (586 in robotic and 585 in laparoscopic group). The pathological TNM stage of the mITT population was 73 (6.2%) patients with complete response, 346 (29.5%) with stage I, 368 (31.4%) with stage II, 384 (32.8%) with stage III. And the median follow-up time was 43.0 months (interquartile range = 36.7 to 60.0), with 34 (2.9%) patients lost to follow-up. The 3-year locoregional recurrence rate in robotic group (1.5%) was significantly lower than in laparoscopic group (4.0%, log-rank p=0.025, hazard ratio = 0.451, 95% confidence interval = 0.221 to 0.921). Robotic group also had significantly higher 3-year disease-free survival rate (87.3% vs. 83.6%, log-rank p=0.035). No significant difference was observed in 3-year overall survival rate (94.8% vs. 93.1%, log-rank p=0.155). Conclusions: Robotic surgery for middle and low rectal cancer significantly reduced locoregional recurrence and improved disease-free survival, compared with conventional laparoscopic surgery. Clinical trial information: NCT02817126 .

Three-year survival data from a phase 2 trial of neoadjuvant short-course radiotherapy followed by chemotherapy and camrelizumab in locally advanced rectal cancer.

e15611 Background: For locally advanced rectal cancer (LARC), short-course radiotherapy (SCRT) or long-course chemoradiotherapy combined with chemotherapy have been the established neoadjuvant treatment, but the optimal therapeutic modality is still under exploration. We previously reported the short-term results of neoadjuvant SCRT followed by chemotherapy and camrelizumab (a PD-1 inhibitor), encouragingly noting pathological complete response (pCR) in 48.1% of LARC patients (Lin Z et al. J Immunother Cancer 2021;9:e003554). Here, we report the further 3-year follow-up results. Methods: Adult patients with histologically confirmed T3-4N0M0 or T1-4N+M0 rectal adenocarcinoma were enrolled. Prior to surgery, eligible patients received 5×5 Gy SCRT, and after one week, they were treated with camrelizumab (200 mg, i.v., on day 1) plus CAPOX chemotherapy (oxaliplatin 130 mg/m2, i.v., on day 1 and capecitabine 1000 mg/m2, orally, bid, on days 1-14) in 21-day cycles for 2 cycles. Radical surgery was performed one week after the last neoadjuvant cycle. For this updated analysis, disease-free survival (DFS) and overall survival (OS) at 3 years are reported. Results: Thirty patients were enrolled and received SCRT, and all of these patients were included in this OS analysis. Among them, 27 patients received camrelizumab plus CAPOX chemotherapy, all of whom underwent surgery and were included in this DFS analysis. Of the 27 patients, 21 patients (77.8%) received at least one cycle of postoperative adjuvant chemotherapy with CAPOX regimen. With a median follow-up of 40.8 months (IQR 40.3-44.3), disease recurrence or death occurred in six (22.2%) patients. The median DFS and OS were both not reached, with the 3-year DFS and OS rates of 80.2% (95% CI 58.6-91.3) and 93.3% (95% CI 75.9-98.3), respectively. Subgroup analysis showed that patients with pCR, postoperative pathological node-negative status, PD-L1 combined positive score ≥ 1, and negative circumferential resection margin and negative extramural venous invasion by MRI at baseline had a tendency towards improved 3-year DFS and OS compared to those without these characteristics. No new or long-term safety signals were identified. Conclusions: With 3 years of extended follow-up, a favorable survival benefit was observed with neoadjuvant SCRT combined with subsequent CAPOX plus camrelizumab followed by delayed surgery in LARC patients. A randomized phase 3 trial (NCT04928807) is ongoing to confirm these results. Clinical trial information: NCT04231552 .

Prolonged interval to surgery following neoadjuvant chemoradiotherapy in locally advanced rectal cancer: A meta-analysis of randomized controlled trials

BackgroundLong-course neoadjuvant chemoradiotherapy (NCRT), followed by surgery after an interval of 6–8 weeks, represents standard of care for patients with locally advanced rectal cancer (LARC). Increasing this interval may improve rates of complete pathological response (pCR) and tumour downstaging. We performed a meta-analysis comparing standard (SI, within 8 weeks) versus longer (LI, after 8 weeks) interval from NCRT to surgery. MethodsPubMed, Embase, and Cochrane databases were searched up to 31 August 2022. Randomized controlled trials (RCTs) comparing SI with LI after NCRT for LARC were included. The primary endpoint was pCR rate. Secondary endpoints included rates of R0 resection, circumferential resection margin positivity (+CRM), TME completeness, lymph node yield (LNY), operative duration, tumour downstaging (TD), sphincter preservation, mortality, postoperative complications, surgical site infection (SSI) and anastomotic leak (AL). Random effects models were used to calculate pooled effect size estimates. ResultsFour RCTs encompassing 867 patients were included. There were 539 males (62.1%). LI was associated with a higher pCR rate (OR 0.61, 95%CI ​= ​0.39–0.95, p ​= ​0.03), and more TD (OR 0.60, 95%CI ​= ​0.37–0.97, p ​= ​0.04) compared to SI. However, there was no difference in rates of R0 resection (p ​= ​0.87), +CRM (p ​= ​0.66), sphincter preservation (p ​= ​0.26), incomplete TME (p ​= ​0.49), LNY (p ​= ​0.55), SSI (p ​= ​0.33), AL (p ​= ​0.20), operative duration (p ​= ​0.07), mortality (p ​= ​0.89) or any surgical complication (p ​= ​0.91). ConclusionsA LI to surgery after NCRT for LARC increases pCR and TD rates. Local recurrence or survival were not assessed due to unavailable data. We recommend deferring TME until after an interval of 8 weeks following completion of NCRT.

Robotic vs laparoscopic abdominoperineal resection for rectal cancer: A propensity score matching cohort study and meta-analysis.

Robotic surgery (RS) is gaining popularity; however, evidence for abdominoperineal resection (APR) of rectal cancer (RC) is scarce. To compare the efficacy of RS and laparoscopic surgery (LS) in APR for RC. We retrospectively identified patients with RC who underwent APR by RS or LS from April 2016 to June 2022. Data regarding short-term surgical outcomes were compared between the two groups. To reduce the effect of potential confounding factors, propensity score matching was used, with a 1:1 ratio between the RS and LS groups. A meta-analysis of seven trials was performed to compare the efficacy of robotic and laparoscopic APR for RC surgery. Of 133 patients, after propensity score matching, there were 42 patients in each group. The postoperative complication rate was significantly lower in the RS group (17/42, 40.5%) than in the LS group (27/42, 64.3%) (P = 0.029). There was no significant difference in operative time (P = 0.564), intraoperative transfusion (P = 0.314), reoperation rate (P = 0.314), lymph nodes harvested (P = 0.309), or circumferential resection margin (CRM) positive rate (P = 0.314) between the two groups. The meta-analysis showed patients in the RS group had fewer positive CRMs (P = 0.04), lesser estimated blood loss (P < 0.00001), shorter postoperative hospital stays (P = 0.02), and fewer postoperative complications (P = 0.002) than patients in the LS group. Our study shows that RS is a safe and effective approach for APR in RC and offers better short-term outcomes than LS.

Robotic versus laparoscopic surgery for colorectal disease: a systematic review, meta-analysis and meta-regression of randomised controlled trials.

Robotic surgery (RS) is gaining prominence in colorectal procedures owing to advantages like three-dimensional vision and enhanced dexterity, particularly in rectal surgery. Although recent reviews report similar outcomes between laparoscopic surgery (LS) and RS, this study investigates the evolving trends in outcomes over time, paralleling the increasing experience in RS. A systematic review, meta-analysis and meta-regression were conducted of randomised controlled trials exploring postoperative outcomes in patients undergoing RS or LS for colorectal pathology. The primary outcome measure was postoperative complications. Risk of bias was evaluated using the Cochrane Collaboration's assessment tool. Randomised controlled trials were identified from the PubMed®, Embase® and CINAHL® (Cumulative Index to Nursing and Allied Health Literature) databases via the Cochrane Central Register of Controlled Trials. Of 491 articles screened, 13 fulfilled the inclusion criteria. Meta-analysis of postoperative complications revealed no significant difference between RS and LS (relative risk [RR]: 0.96, 95% confidence interval [CI]: 0.79 to 1.18, p=0.72). Meta-regression analysis of postoperative complications demonstrated a significant trend favouring RS over time (yearly change in Ln(RR): -0.0620, 95% CI: -0.1057 to -0.0183, p=0.005). Secondary outcome measures included operative time, length of stay, blood loss, conversion to open surgery, positive circumferential resection margins and lymph nodes retrieved. The only significant findings were shorter operative time favouring LS (mean difference: 41.48 minutes, 95% CI: 22.15 to 60.81 minutes, p<0.001) and fewer conversions favouring RS (RR: 0.57, 95% CI: 0.37 to 0.85, p=0.007). As experience in RS grows, evidence suggests an increasing safety profile for patients. Meta-regression revealed a significant temporal trend with complication rates favouring RS over LS. Heterogeneous reporting of complications hindered subgroup analysis of minor and major complications. LS remains quicker. Rising adoption of RS coupled with emerging evidence is expected to further elucidate its clinical efficacy.

A novel perineal exposure method in laparoscopic abdominal perineal resection of rectal cancer: a case series study

BackgroundAbdominal perineal resection (APR) of rectal cancer, also known as Mile’s procedure, is a classic procedure for the treatment of rectal cancer. Through the improvement of surgical skills and neoadjuvant therapy, the sphincter-preserving rate in rectal cancer patients has improved, even in patients with ultralow rectal cancer who underwent APR in the past. However, APR cannot be completely replaced by low anterior resection (LAR) in reality. APR still has its indications, when the tumor affects the external sphincter, etc. Good perineal exposure in APR is difficult and can seriously affect surgical safety and the long-term prognosis.MethodsWe reviewed the records of 16 consecutive patients with rectal cancer who underwent APR at Anqing Municipal Hospital from January 2022 to April 2023, including 11 males and 5 females, with an average age of 64.8 ± 10.3 years. The perineal operation was completed with the Lone-Star® retractor-assisted (LSRA) exposure method. After incising the skin and subcutaneous tissue, a Lone-Star® retractor was placed, and the incision was retracted in surrounding directions with 8 small retractors, which facilitated the freeing of deep tissues. We dynamically adjusted the retractor according to the plane to fully expose the surgical field.ResultsAll 16 patients underwent laparoscopic-assisted APR successfully. Thirteen procedures were performed independently by a single person, and the others were completed by two persons due to intraoperative arterial hemostasis. All specimens were free of perforation and had a negative circumferential resection margin (CRM). Postoperative complications occurred in 4 patients, including urinary retention in 1 patient, pulmonary infection in 1 patient, intestinal adhesion in 1 patient and peristomal dermatitis in 1 patient, and were graded as ClavienDindo grade 3 or lower and cured. No distant metastasis or local recurrence was found for any of the patients in the postoperative follow-up.ConclusionsThe application of the LSRA exposure method might be helpful for perineal exposure during APR for rectal cancer, which could improve intraoperative safety and surgical efficiency, achieve one-person operation, and increase the comfort of operators.