Risk of local recurrence of rectal cancer and circumferential resection margin: population-based cohort study

An International Multicentre Retrospective Cohort Study Evaluating Robot-Assisted Total Mesorectal Excision in Experienced Dutch, French, and United Kingdom Centres-The EUREKA Collaborative

BACKGROUND

Robot-assisted total mesorectal excision has been proposed as an alternative to laparoscopic TME for rectal cancer. However, its short-term outcomes and long-term oncological efficacy remain debated, especially in Western populations. This study evaluates the short-term clinical and long-term oncological outcomes of robot-assisted total mesorectal excision performed by experienced surgeons in high-volume European centres.

METHODS

This multicentre, international, retrospective cohort study included 1390 patients from the EUREKA collaborative dataset who underwent robot-assisted total mesorectal excision for rectal cancer between January 2013 and January 2022. All surgeries were performed by expert surgeons beyond the learning curve. Data were analysed for patient demographics, perioperative outcomes, pathological findings, and three-year survival metrics. Kaplan-Meier analysis was used to evaluate overall and disease-free survival.

RESULTS

Of 1390 patients, 60.6% underwent restorative low anterior resection. Conversion to open surgery occurred in 3.7%, and postoperative complications were reported in 28.7%. Anastomotic leakage occurred in 14.7% of patients who underwent restorative low anterior resection. The median operative time was 223 min. R0 resection was achieved in 94.7%, and circumferential resection margin positivity was 5.5%. Three-year overall survival was 90.1%, disease-free survival was 88.6%, and local recurrence was 2.9%.

CONCLUSIONS

Robot-assisted total mesorectal excision performed by experienced surgeons in high-volume European centres is safe, with low conversion rates, acceptable complication rates, and favourable oncological outcomes. These findings underscore the potential of robot-assisted total mesorectal excision as a standard approach for rectal cancer in specialised settings.

Predictive value of magnetic resonance imaging parameters combined with tumor markers for rectal cancer recurrence risk after surgery

BACKGROUND

An increasing number of studies to date have found preoperative magnetic resonance imaging (MRI) features valuable in predicting the prognosis of rectal cancer (RC). However, research is still lacking on the correlation between preoperative MRI features and the risk of recurrence after radical resection of RC, urgently necessitating further in-depth exploration.

AIM

To investigate the correlation between preoperative MRI parameters and the risk of recurrence after radical resection of RC to provide an effective tool for predicting postoperative recurrence.

METHODS

The data of 90 patients who were diagnosed with RC by surgical pathology and underwent radical surgical resection at the Second Affiliated Hospital of Bengbu Medical University between May 2020 and December 2023 were collected through retrospective analysis. General demographic data, MRI data, and tumor markers levels were collected. According to the reviewed data of patients six months after surgery, the clinicians comprehensively assessed the recurrence risk and divided the patients into high recurrence risk (37 cases) and low recurrence risk (53 cases) groups. Independent sample t-test and χ² test were used to analyze differences between the two groups. A logistic regression model was used to explore the risk factors of the high recurrence risk group, and a clinical prediction model was constructed. The clinical prediction model is presented in the form of a nomogram. The receiver operating characteristic curve, Hosmer-Lemeshow goodness of fit test, calibration curve, and decision curve analysis were used to evaluate the efficacy of the clinical prediction model.

RESULTS

The detection of positive extramural vascular invasion through preoperative MRI [odds ratio (OR) = 4.29, P = 0.045], along with elevated carcinoembryonic antigen (OR = 1.08, P = 0.041), carbohydrate antigen 125 (OR = 1.19, P = 0.034), and carbohydrate antigen 199 (OR = 1.27, P < 0.001) levels, are independent risk factors for increased postoperative recurrence risk in patients with RC. Furthermore, there was a correlation between magnetic resonance based T staging, magnetic resonance based N staging, and circumferential resection margin results determined by MRI and the postoperative recurrence risk. Additionally, when extramural vascular invasion was integrated with tumor markers, the resulting clinical prediction model more effectively identified patients at high risk for postoperative recurrence, thereby providing robust support for clinical decision-making.

CONCLUSION

The results of this study indicate that preoperative MRI detection is of great importance for predicting the risk of postoperative recurrence in patients with RC. Monitoring these markers helps clinicians identify patients at high risk, allowing for more aggressive treatment and monitoring strategies to improve patient outcomes.

Does Extramural Vascular Invasion Predict Response to Neoadjuvant Therapy in Locally Advanced Rectal Cancer?

INTRODUCTION

Extramural vascular invasion (EMVI) is associated with distant recurrence after treatment of locogionally advanced rectal adenocarcinomas (LARCs), but its use as a marker for response to neoadjuvant therapy is less well understood. We examined the relationship between EMVI and tumor or nodal category downstaging after treatment of LARCs with neoadjuvant therapy.

METHODS

Patients with EMVI categorized on initial staging pelvic MRI for LARC who underwent curative-intent surgery after neoadjuvant therapy at MD Anderson Cancer Center from 2016 to 2022 were identified. Patients received either preoperative chemoradiation or total neoadjuvant therapy (TNT). Associations between EMVI and demographic, radiologic, and clinicopathologic variables were analyzed.

RESULTS

EMVI was associated with higher rates of lymphovascular invasion (LVI) (46.2% vs. 27.8%, P = .001) and perineural invasion (PNI) (51.9% vs. 28.4%, P < .001) on final pathology. Patients with EMVI were more likely to have cT4 tumors (31.7% vs. 16.3%, P = .004) and cN+ status (86.8% vs. 66.3%, P = .001) and more likely to be treated with TNT rather than chemoradiation alone (62.3% vs. 41.9%, P = .005). EMVI was associated with a lower rate of pathologic complete or near-complete response (20.1% vs. 34.2%, P = .018), downstaging to ypT0-2 from cT3/4 tumors (14.9% vs. 44.4%, P = .0001), and downstaging to ypN0 from cN+ status (47.9% vs. 66.4%, P = .015).

CONCLUSIONS

Rectal tumors with EMVI are more likely to have higher clinical stage, less likely to respond to neoadjuvant therapy despite increased use of TNT, and more likely to have high-risk features for recurrence. This suggests EMVI is a marker of disease with poorer response to neoadjuvant therapy. Disease biology should be strongly considered in treatment decision-making, and new treatment strategies are needed to improve disease response.

Risk factors and treatment strategies for local recurrence of locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by total mesorectal excision

BACKGROUND

Despite advancements in total mesorectal excision (TME) and neoadjuvant radiotherapy, locally advanced rectal cancer remains challenging, impacting patient quality of life and mortality. This study aimed to identify the risk factors for local recurrence in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy (CRT) and assess treatment strategies for recurrence.

METHODS

This retrospective analysis included 682 patients diagnosed with locally advanced rectal cancer who were treated with neoadjuvant CRT and TME at Samsung Medical Center from 2008 to 2017. The exclusion criteria ensured a homogenous cohort. Clinical staging involved colonoscopies, computed tomography, magnetic resonance imaging, and digital rectal exam. Risk factors, treatment modalities, and oncological outcomes for local recurrence were evaluated.

RESULT

During a median 62-month follow-up, 47 patients (6.9 %) experienced local recurrence. The risk factors for local recurrence included a positive circumferential resection margin (CRM), venous invasion, and perineural invasion. Of the 47 patients with local recurrence, 25 (53.2 %) were considered resectable. Out of these, 23 patients underwent curative resections, and 15 (65.2 %) achieved R0 resection. Patients with R0 resections exhibited superior 5-year survival rates compared to R1-2 resection or non-surgical treatment, and there was no survival difference between R1-2 resection and non-surgical treatment.

CONCLUSION

In locally advanced rectal cancer, positive CRM, venous invasion, and perineural invasion were associated with local recurrence. R0 resection showed favorable outcomes, emphasizing the importance of surveillance in high-risk patients. Treatment decisions should consider these factors for improved oncologic outcomes and quality of life.

Oncological and Clinical Impacts of Routine Splenic Flexure Mobilization in Anterior Resection

Background Splenic flexure mobilization (SFM) is widely regarded as one of the most challenging steps in laparoscopic and robotic colorectal surgery, sparking ongoing debate. Some surgeons routinely advocate for SFM, citing its role in achieving greater left colonic reach, which facilitates a safe, tension-free, and well-vascularized anastomosis while adhering to oncological principles. Conversely, others argue that SFM does not consistently ensure these benefits and may increase the risk of complications, including splenic, bowel, or vascular injuries, as well as unnecessarily prolonging the procedure. While traditional surgical textbooks consider SFM a mandatory step in open colorectal resections, limited evidence supports its necessity in minimally invasive approaches. Aim This study aims to evaluate whether routinely mobilizing the splenic flexure offers advantages from both oncological and clinical perspectives. Materials and methods This retrospective cohort study evaluated the oncological and clinical outcomes of SFM versus splenic flexure preservation (SFP) in anterior resections for malignant pathologies. The study was conducted at New Cross Hospital in Wolverhampton, United Kingdom, over a 24-month period, from March 2022 to March 2024. Anterior resections for benign pathologies were excluded. Data analysis was performed using IBM SPSS Statistics for Windows, Version 24.0 (Released 2016; IBM Corp., Armonk, NY, USA) and Microsoft Excel (Microsoft Corporation, Redmond, WA, USA). Results This study included 94 patients, with 65 undergoing SFM and 29 having it preserved (SFP). No significant differences in baseline demographics (age and gender) were observed between the groups. Oncological outcomes revealed a significantly longer median length of resected specimens in the SFM group, although lymph node counts and high vascular ties were comparable between the groups. There were no differences in R0 resection rates. Clinical outcomes showed similar hospital stays and operation durations in both groups. The SFM group had a slightly higher rate of stoma formation but a lower incidence of anastomotic leaks compared to the SFP group. No significant differences in splenic injuries or other complications were noted. Conclusions Our study suggests that routine SFM offers certain oncological and clinical benefits. The specimens obtained were more complete for pathological staging. The additional length gained from the maneuver not only results in longer specimens but also provides sufficient mobility of the remaining colon, enabling anastomosis with minimal tension, which helps prevent anastomotic leaks. Surgeons may consider adjusting their practices based on the findings of this study.

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

BACKGROUND

The 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.

METHODS

The 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.

RESULTS

A 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.

CONCLUSIONS

Readily 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.

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

INTRODUCTION

The 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.

METHODS

This 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.

RESULTS

Complete 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).

CONCLUSIONS

Both 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.

Robotic-assisted low anterior resection for rectal cancer shows similar clinical efficacy to laparoscopic surgery: A propensity score matched study

BACKGROUND

Rectal cancer ranks as the second leading cause of cancer-related mortality worldwide, necessitating surgical resection as the sole treatment option. Over the years, there has been a growing adoption of minimally invasive surgical techniques such as robotic and laparoscopic approaches. Robotic surgery represents an innovative modality that effectively addresses the limitations associated with traditional laparoscopic techniques. While previous studies have reported favorable perioperative outcomes for robot-assisted radical resection in rectal cancer patients, further evidence regarding its oncological safety is still warranted.

AIM

To conduct a comparative analysis of perioperative and oncological outcomes between robot-assisted and laparoscopic-assisted low anterior resection (LALAR) procedures.

METHODS

The clinical data of 125 patients who underwent robot-assisted low anterior resection (RALAR) and 279 patients who underwent LALAR resection at Shandong Provincial Hospital Affiliated to Shandong First Medical University from December 2019 to November 2022 were retrospectively analyzed. After performing a 1:1 propensity score matching, the patients were divided into two groups: The RALAR group and the LALAR group (111 cases in each group). Subsequently, a comparison was made between the short-term outcomes within 30 d after surgery and the 3-year survival outcomes of these two groups.

RESULTS

Compared to the LALAR group, the RALAR group exhibited a significantly earlier time to first flatus [2 (2-2) d vs 3 (3-3) d, P = 0.000], as well as a shorter time to first fluid diet [4 (3-4) d vs 5 (4-6) d, P = 0.001]. Additionally, the RALAR group demonstrated reduced postoperative indwelling catheter time [2 (1-3) d vs 4 (3-5) d, P = 0.000] and decreased length of hospital stay after surgery [5 (5-7) d vs 7(6-8) d, P = 0.009]. Moreover, there was an observed increase in total cost of hospitalization for the RALAR group compared to the LALAR group [10777 (10780-11850) dollars vs 10550 (8766-11715) dollars, P = 0.012]. No significant differences were found in terms of conversion rate to laparotomy or incidence of postoperative complications between both groups. Furthermore, no significant disparities were noted regarding the 3-year overall survival rate and 3-year disease-free survival rate between both groups.

CONCLUSION

Robotic surgery offers potential advantages in terms of accelerated recovery of gastrointestinal and urologic function compared to LALAR resection, while maintaining similar perioperative and 3-year oncological outcomes.

Hartmann's Procedure Versus Intersphincteric Abdominoperineal Excision in Patients with Rectal Cancer: Report from the Swedish Colorectal Cancer Registry (SCRCR)

Objective

The primary outcome was to compare overall postoperative surgical complications within 30 days after Hartmann's procedure (HP) compared with intersphincteric abdominoperineal excision (iAPE). The secondary outcome was major surgical complications (Clavien-Dindo ≥ III).

Background

There is uncertainty regarding the optimal surgical method in patients with rectal cancer when an anastomosis is unsuitable.

Methods

Rectal cancer patients with a tumor height >5 cm, registered in the Swedish Colorectal Cancer Registry who received HP or iAPE electively in 2017-2020 were included, (HP, n = 696; iAPE, n = 314). Logistic regression analysis adjusting for body mass index, American Society of Anesthesiologists classification, sex, age, preoperative radiotherapy, tumor height, cancer stage, operating hospital, and type of operation was performed.

Results

Patients in the HP group were older and had higher American Society of Anesthesiologists scores. The mean operating time was less for HP (290 vs 377 min). Intraoperative bowel perforations were less frequent in the HP group, 3.6% versus 10.2%. Overall surgical complication rates were 20.3% after HP and 15.9% after iAPE (P = 0.118). Major surgical complications were 7.5% after HP and 5.7% and after iAPE (P = 0.351). Multiple regression analysis indicated a higher risk of overall surgical complications after HP (odds ratio: 1.63; 95% confidence interval = 1.09-2.45).

Conclusions

HP was associated with a higher risk of surgical complications compared with iAPE. In patients unfit for anastomosis, iAPE may be preferable. However, the lack of statistical power regarding major surgical complications, prolonged operating time, increased risk of bowel perforation, and lack of long-term outcomes, raises uncertainty regarding recommending intersphincteric abdominoperineal excision as the preferred surgical approach.

Development of a joint prediction model based on both the radiomics and clinical factors for preoperative prediction of circumferential resection margin in middle-low rectal cancer using T2WI images

OBJECTIVES

A circumferential resection margin (CRM) is an independent risk factor for local recurrence, distant metastasis, and poor overall survival of rectal cancer. In this study, we developed and validated a radiomics prediction model to predict perioperative surgical margins in patients with middle and low rectal cancer following neoadjuvant treatment and for decisions about treatment plans for patients.

METHODS

This study retrospectively analyzed 275 patients from center 1(training cohort) and 120 patients from center 2(verification cohort) with rectal cancer diagnosed at two centers from July 2020 to July 2022 who underwent neoadjuvant therapy and had their CRM status confirmed by preoperative high-resolution magnetic resonance imaging (MRI) scans. Radiomics signatures were extracted and screened from MRI images and a radiomics signature was built by the least absolute shrinkage and selection operator (LASSO) logistic regression model, which was combined with clinical signatures to construct a nomogram. The receiver operating characteristic (ROC) curve and area under the curve (AUC) value, sensitivity, specificity, positive predictive value, negative predictive value, and calibration curve were used to evaluate the predictive performance of the model.

RESULTS

In our research, the combined model has the best performance. In the training group, the radiomics model based on high-spatial-resolution T2-weighted imaging (HR-T2WI), clinical model and combined model demonstrated an AUC of 0.819 (0.802-0.833), 0.843 (0.822-0.861), and 0.910 (0.880-0.940), respectively. In the validation group, they demonstrated an AUC of 0.745 (0.715-0.788), 0.827 (0.798-0.850), and 0.848 (0.779-0.917), respectively. The calibration curve confirmed the clinical applicability of the model.

CONCLUSIONS

The individualized prediction model established by combining radiomics signatures and clinical signatures can efficiently and objectively predict perioperative margin invasion in patients with middle and low rectal cancer.

Development of a Predictive Nomogram for Circumferential Resection Margin in Rectal Cancer Surgery

INTRODUCTION

Circumferential resection margin (CRM) is a key quality metric and predictor of oncologic outcomes and overall survival following surgery for rectal cancer. We aimed to develop a nomogram to identify patients at risk for a positive CRM in the preoperative setting.

METHODS

We performed a retrospective evaluation of the National Cancer Database from 2010 to 2014 for patients with clinical stage I-III rectal cancer who underwent total mesorectal excision. Patients were excluded for emergency operation, resection for cancer recurrence, palliative resection, transanal resection, and missing CRM status. The primary outcome was positive CRM. Secondary outcomes included overall survival.

RESULTS

There were 28,790 patients included. 2245 (7.8%) had a positive CRM. Higher tumor grade, lack of neoadjuvant chemotherapy, mucinous/signet tumor histology, open approach, abdominoperineal resection, higher T stage, lymphovascular invasion, and perineural invasion were all significantly associated with positive CRM (P < 0.05) and were included in the nomogram. The C-statistic was 0.703, suggesting a good predictive model.

CONCLUSIONS

Positive CRM is associated with specific patient demographics and tumor characteristics. These factors can be used along with preoperative MRI to predict CRM positivity in the preoperative period and plan accordingly.

Risk factors and incidence of non-closure stoma in patients with anterior resection of rectal cancer with temporary stoma: A systematic review and meta-analysis

BACKGROUND

To further define the risk factors and incidence of non-closure stoma in patients with anterior resection of rectal cancer with temporary stoma.

METHODS

Records from five English databases and four Chinese databases. Odds ratios (OR) and 95 % confidence intervals (CI) were used to indicate the risk of inclusion of risk factors. The non-closure stoma rate used the risk difference (RD) and 95 % CI. Risk factors were evaluated for quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

Risk factors of non-closure stoma in patients with anterior resection of rectal cancer with temporary stoma were Age ≥60 years[OR:1.57, 95%CI(1.44,1.72)], Tumor IV stage[OR:4.21, 95%CI(2.29,7.74)], American Society of Anesthesiologists (ASA)≥3[OR:1.48, 95%CI(1.33,1.65)], Neoadjuvant chemoradiotherapy[OR:1.41, 95%CI(1.09,1.82)],Open surgery[OR:1.45, 95%CI(1.09,1.93)], Postoperative chemotherapy[OR:1.37, 95%CI(1.03,1.82)], Anastomotic leakage[OR:4.61, 95%CI(2.86, 7.44)], Local recurrence[OR:7.16, 95%CI(4.70, 10.91)]. The rate of non-closure stoma after anterior resection for rectal cancer was: 0.20, 95 % CI (0.17, 0.23). The quality of evidence for stage IV tumors and anastomotic leakage was moderate, and other risk factors were low to very low.

CONCLUSIONS

Risk factors of non-closure stoma in patients with anterior resection of rectal cancer with temporary stoma were Age≥60 years, Tumor IV stage, ASA≥3, Neoadjuvant chemoradiotherapy, Open surgery, Postoperative chemotherapy, Anastomotic leakage, Local recurrence, and one in five anterior resection patients with a temporary stoma fails to close.

Does robotic TME bring difference in lymph node yield and quality of TME?

BACKGROUNDS

Oncological outcomes of the robotic low anterior rectal resection with total mesorectal excision (TME) are still under discussion. Few studies have proven that robotic TME (rTME) is a safe and equivalent method for treatment of rectal carcinoma. But there is almost no comparison between the rTME and conventional TME in terms of the number of lymph nodes obtained and the quality of the TME.

METHODS

A single institution retrospective study was designed in a cohort of 261 patients. Cohort was divided into two groups depending on the type of surgery (rTME versus TME) and within these two groups, patients were divided according to whether they underwent neoadjuvant chemoradiation (nCHRT) or did not. The primary objective of the study was to compare obtained number of the lymph nodes in specimen. Secondary objectives were comparison of the quality of the TME and the number of positive circumferential resection margins.

RESULTS

Results of the study have shown no significant difference in number of the lymph nodes obtained by the rTME and TME. There was no difference in the quality of the TME, neither in the group with the previous nCHRT nor in the group without a nCHRT.

CONCLUSION

With results from the study we consider the rTME to be non-inferior to the conventional TME. Therefore, at least identical oncological results can be expected in patients treated by the rTME.

Accuracy of Ex-vivo Fluorescence Confocal Microscopy in Margin Assessment of Solid Tumors: A Systematic Review

Fluorescence confocal microscopy (FCM) is a novel technology that enables rapid high-resolution digital imaging of non-formalin-fixed tissue specimens and offers real-time positive surgical margin identification. In this systematic review, we evaluated the accuracy metrics of ex vivo FCM for intraoperative margin assessment of different tumor types. A systematic search of MEDLINE via PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus was performed for relevant papers (PROSPERO ID: CRD42022372558). We included 14 studies evaluating four types of microscopes in six different tumor types, including breast, prostate, central nervous system, kidney, bladder, and conjunctival tumors. Using the Quality Assessment of Diagnostic Accuracy Studies tool, we identified a high risk of bias in patient selection (21%) and index test (36%) of the included studies. Overall, we found that FCM has good accuracy metrics in all tumor types, with high sensitivity and specificity (>80%) and almost perfect concordance (>90%) against final pathology results. Despite these promising findings, the quality of the available evidence and bias concerns highlight the need for adequately designed studies to further define the role of ex vivo FCM in replacing the frozen section as the tool of choice for intraoperative margin assessment.

Circumferential Resection Margin is Associated With Distant Metastasis After Rectal Cancer Surgery: A Nation-wide Population-based Study Cohort

OBJECTIVE

To evaluate circumferential resection margin (CRM) as a risk factor for distant metastasis (DM) in rectal cancer.

SUMMARY OF BACKGROUND DATA

The treatment of rectal cancer has evolved over the last decades. Surgical radicality is considered the most important factor in preventing recurrences including local and distant. CRM ≤1.0 mm is considered to increase recurrence risk. This study explores the risk of DM in relation to exact CRM.

METHODS

All patients treated with abdominal resection surgery for rectal cancer between 2005 and 2013 in Sweden were eligible for inclusion in this retrospective study. Primary endpoint was DM.

RESULTS

Twelve thousand one hundred forty-six cases were identified. Eight thousand five hundred ninety-three cases were analyzed after exclusion. Seven hundred seventeen (8.6%) patients had CRM ≤1.0mm and 7577 (91.4%) patients had CRM >1.0 mm. DM recurrence rate at 5 years was 42.1% (95% CI 32.5-50.3), 31.5% (95% CI 27.3-35.5), 25.8% (95% Confidence Interval (CI) 16.2-34.4), and 19.5% (95% CI 18.5-19.5) when CRM was 0.0 mm, 0.1 to 1.0 mm, 1.1 to 1.9 mm, and CRM ≥2mm, respectively. Multivariable analysis revealed higher DM risk in CRM 0.0-1.0 mm versus >1.0 mm (hazard ratio 1.30, 95% CI 1.05-1.60; P = 0.015). No significant difference in DM risk in CRM 1.1-1.9 mm versus ≥2.0 mm (hazard ratio 0.66, 95% CI 0.34-1.28; P = 0.224) could be detected.

CONCLUSIONS

The risk of DM decreases with increasing CRM. Moreover, CRM ≤1.0 mm is a significant risk factor for DM. Thus, CRM is a dominant factor when discussing risk of DM after rectal cancer surgery.

Association of levels of metabolites with the safe margin of rectal cancer surgery: a metabolomics study

Background

Rectal cancer is one of the most lethal of gastrointestinal malignancies. Metabonomics has gradually developed as a convenient, inexpensive and non-destructive technique for the study of cancers.

Methods

A total of 150 tissue samples from 25 rectal cancer patients were analyzed by liquid chromatography–mass spectrometry (LC–MS), and 6 tissue samples were collected from each patient (group 1: tumor; group 2: 0.5 cm from tumor; group 3:1 cm from tumor; group 4:2 cm from tumor; group 5:3 cm from tumor and group 6:5 cm from tumor). The differential metabolites of tumor tissues and 5 cm from the tumor (normal tissues) were first selected. The differential metabolites between tumor tissues and normal tissues were regrouped by hierarchical clustering analysis, and further selected by discriminant analysis according to the regrouping of clustering results. The potential safe margin of clinical T(cT)1,cT2 stage rectal cancer and cT3,cT4 stage rectal cancer at the metabolomic level was further identified by observing the changes in the level of differential metabolites within the samples from group 1 to group 6.

Results

We found 22 specific metabolites to distinguish tumor tissue and normal tissue. The most significant changes in metabolite levels were observed at 0.5 cm (cT1, cT2) and 2.0 cm (cT3, cT4) from the tumor, while the changes in the tissues afterwards showed a stable trend.

Conclusions

There are differential metabolites between tumor tissues and normal tissues in rectal cancer. Based on our limited sample size, the safe distal incision margin for rectal cancer surgery in metabolites may be 0.5 cm in patients with cT1 and cT2 stage rectal cancer and 2.0 cm in patients with cT3 and cT4 stage rectal cancer.

Nomogram to predict permanent stoma in rectal cancer patients after sphincter-saving surgery

BACKGROUND

Approximately 20 percent of patients with a tumour localized in the low rectum still encounter the possibility of requiring permanent stoma (PS), which can cause drastic changes in lifestyle and physical perceptions.

AIM

To determine the risk factors for PS and to develop a prediction model to predict the probability of PS in rectal cancer patients after sphincter-saving surgery.

METHODS

A retrospective cohort of 421 rectal cancer patients who underwent radical surgery at Taipei Medical University Hospital between January 2012 and December 2020 was included in this study. Univariate and multivariate analyses were performed to identify the independent risk factors for PS. A nomogram was developed according to the independent risk factors obtained in the multivariate analysis. The performance of the nomogram was assessed using a receiver operating characteristic curve and a calibration curve.

RESULTS

The PS rate after sphincter-saving surgery was 15.1% (59/391) in our study after a median follow-up of 47.3 mo (range 7–114 mo). Multivariate logistic regression analysis demonstrated that local recurrence, perirectal abscess, anastomosis site stenosis, perineural invasion, tumor size and operative time were independent risk factors for PS. These identified risk factors were incorporated into the nomogram, and the concordance index of this model was 0.903 (95%CI: 0.851-0.955). According to the calibration curves, the nomogram represents a perfect prediction model.

CONCLUSION

Several risk factors for PS after sphincter-saving surgery were identified. Our nomogram exhibited perfect predictive ability and will improve a physician’s ability to communicate the benefits and risks of various treatment options in shared decision making.

A nomogram for predicting 10-year cancer specific survival in patients with pathological T3N0M0 rectal cancer

Background

The pathological T3N0M0 (pT3N0M0) rectal cancer is the earliest stage and has the best prognosis in the locally advanced rectal cancer, but the optimal treatment remains controversial. A reliable prognostic model is needed to discriminate the high-risk patients from the low-risk patients, and optimize adjuvant chemotherapy (ACT) treatment decisions by predicting the likelihood of ACT benefit for the target population.

Patients and methods

We gathered and analyzed 276 patients in Sun Yat-sen University Cancer Center from March 2005 to December 2011. All patients underwent total mesorectal excision (TME), without preoperative therapy, and were pathologically proven pT3N0M0 rectal cancer with negative circumferential resection margin (CRM). LASSO regression model was used for variable selection and risk factor prediction. Multivariable cox regression was used to develop the predicting model. Optimum cut-off values were determined using X-Tile plot analysis. The 10-fold cross-validation was adopted to validate the model. The performance of the nomogram was evaluated with its calibration, discrimination and clinical usefulness.

Results

A total of 188 patients (68.1%) had ACT and no patients had adjuvant radiotherapy. Age, monocyte percentage, carbohydrate antigen 19–9, lymph node dissection numbers and perineural invasion (PNI) were identified as significantly associated variables that could be combined for an accurate prediction risk of Cancer Specific Survival (CSS) for pT3N0M0 patients. The model adjusted for CSS showed good discrimination with a C-index of 0.723 (95% CI: 0.652–0.794). The calibration curves showed that the nomogram adjusted for CSS was able to predict 3-, 5-, and 10-year CSS accurately. The corresponding predicted probability was used to stratify high and low-risk patients (10-year CSS: 69.1% vs. 90.8%, HR = 3.815, 95%CI: 2.102–6.924, P < 0.0001). ACT improved overall survival (OS) in the low-risk patients (10-year OS: 91.9% vs. 83.3%, HR = 0.338, 95% CI: 0.135–0.848, P < 0.0001), while it did not exhibit a significant benefit in the high-risk patients.

Conclusion

The present study showed that age, monocyte percentage, carbohydrate antigen 19–9, lymph node dissection numbers and PNI were independent prognostic factors for pT3N0M0 rectal cancer patients. A nomogram based on these prognostic factors effectively predicts CSS in patients, which can be conveniently used in clinical practice. ACT may improve overall survival in the low-risk patients. But the benefit of ACT was not seen in the high-risk patients.

Intraoperative adverse events as a risk factor for local recurrence of rectal cancer after resection surgery

AIM

Failure to achieve a radical resection as well as intraoperative rectal perforation are important risk factors for local recurrence after rectal cancer surgery, but the importance of other intraoperative adverse events for the prognosis is unknown. The aim of this study was to assess the occurrence of intraoperative adverse events during rectal cancer surgery, and to determine whether these were associated with an increased risk of local recurrence.

METHODS

A retrospective population-based cohort study was undertaken, including all patients in Region Västra Götaland, Sweden, who had undergone primary resection surgery for rectal cancer diagnosed between 2010 and 2014, registered in the Swedish Colorectal Cancer Registry. Data were retrieved from the registry and through review of the medical records.

RESULTS

In total, 1208 patients were included in the study of whom 78 (6%) developed local recurrence during the follow-up period of at least 5 years. Intraoperative adverse events were common and occurred in 62/78 (79%) of patients with local recurrence compared to 604/1130 (53%) of patients without local recurrence. In multivariate analysis intraoperative adverse events were found to be an independent risk factor for local recurrence of rectal cancer, as were nonradical resection, a high pathological T stage, the presence of lymph node metastases, type of surgery and refraining from rectal washout during anterior resection and Hartmann's procedure.

CONCLUSIONS

Intraoperative adverse events were found to be an independent risk factor for local recurrence of rectal cancer and could possibly be used together with other known risk factors to select patients for intensified postoperative surveillance.

Omission of neoadjuvant radiotherapy for clinical T2/N1 and T3N0/1 middle and low rectal cancers with safe circumferential resection margins

Purpose

For moderately advanced rectal cancers with safe circumferential margins, the oncologic benefit of neoadjuvant radiotherapy must be reconsidered because of the possibility of overtreatment, resulting in complications from radiotoxicity. To evaluate the oncologic safety of the omission of neoadjuvant radiotherapy for moderately advanced rectal cancers, we evaluated and compared the prognoses of patients who underwent radical resection with and without neoadjuvant radiotherapy for T2/N1 and T3N0/1 middle and low rectal cancers with safe circumferential resection margins.

Methods

We retrospectively enrolled 66 patients who underwent radical resection for clinical (c) T2N1 and T3N0/1 middle and low rectal cancers between 2008 and 2014. Patients with distant metastasis; cT4, cN2, or positive lateral pelvic lymph nodes; positive circumferential resection margin; signet-ring cell carcinoma; cT1/2N0; or those who had received adjuvant radiotherapy were excluded. The clinical and pathological characteristics and 5-year oncologic outcomes of the no-radiotherapy (n = 34) and radiotherapy (n = 32) groups were compared.

Results

The rates of abdominoperineal resection and ileostomies and the proportion of patients who received adjuvant chemotherapy were significantly higher in the radiotherapy group. There were no significant differences in tumor location, clinical stage, surgery type, pathologic N stage, anastomotic leakage, or long-term oncologic outcomes including 5-year disease-free survival, overall survival, and local recurrence and distant metastasis rates between both groups.

Conclusion

The oncologic benefit of neoadjuvant radiotherapy for cT2/N1 and T3N0/1 middle and low rectal cancers with safe circumferential resection margins is considered unclear, and it can be omitted to prevent radiotoxicity and facilitate prompt essential treatment.

Surgical treatment of locally recurrent rectal cancer: a narrative review

Objective

To summarize the recent literature on surgical treatment of locally recurrent rectal cancer (LRRC).

Background

LRRC is a heterogeneous disease that requires a multidisciplinary treatment approach. The treatment and prognosis depend on the site and type of recurrence. Radical resection remains the primary method for achieving long-term survival and improving symptom control. Preoperative chemoradiotherapy can reduce tumor volume and improve the R0 resection rate. Surgeons must clearly understand pelvic anatomy, develop a detailed preoperative plan, adopt a multidisciplinary approach for the surgical resection of the tumor as well as any invaded soft tissues, vessels, and bones, and ensure proper reconstruction. However, extended radical surgery often leads to a higher risk of postoperative complications and a low quality of life.

Methods

We searched English-language articles with keywords “locally recurrent rectal cancer”, “surgery” and “multidisciplinary team” in PubMed published between January 2000 to October 2020.

Conclusions

LRRC is a complex problem. Long-term survival is not impossible following multidisciplinary treatment in appropriately selected LRRC patients. The management of LRRC relies on a specialist team that determines the biological behavior of the tumor and evaluates treatment options through multidisciplinary discussions, thereby balancing the surgical costs and benefits, alleviating postoperative complications, and improving patients’ quality of life.

The "Real R0": A Resection Margin Smaller Than 0.1 cm is Associated with a Poor Prognosis After Oncologic Esophagectomy

Background

Although resection margin (R) status is a widely used prognostic factor after esophagectomy, the definition of positive margins (R1) is not universal. The Royal College of Pathologists considers R1 resection to be a distance less than 0.1 cm, whereas the College of American Pathologists considers it to be a distance of 0.0 cm. This study assessed the predictive value of R status after oncologic esophagectomy, comparing survival and recurrence among patients with R0 resection (> 0.1-cm clearance), R0+ resection (≤ 0.1-cm clearance), and R1 resection (0.0-cm clearance).

Methods

The study enrolled all eligible patients undergoing curative oncologic esophagectomy between 2012 and 2018. Clinicopathologic features, survival, and recurrence were compared for R0, R0+, and R1 patients. Categorical variables were compared with the chi-square or Fisher’s test, and continuous variables were compared with the analysis of variance (ANOVA) test, whereas the Kaplan-Meier method and Cox regression were used for survival analysis.

Results

Among the 160 patients included in this study, 113 resections (70.6%) were R0, 34 (21.3%) were R0+, and 13 (8.1%) were R1. The R0 patients had a better overall survival (OS) and disease-free survival (DFS) than the R0+ and R1 patients. The R0+ resection offered a lower long-term recurrence risk than the R1 resection, and the R status was independently associated with DFS, but not OS, in the multivariate analysis. Both the R0+ and R1 patients had significantly more adverse histologic features (lymphovascular and perineural invasion) than the R0 patients and experienced more distant and locoregional recurrence.

Conclusions

Although R status is an independent predictor of DFS after oncologic esophagectomy, the < 0.1-cm definition for R1 resection seems more appropriate than the 0.0-cm definition as an indicator of poor tumor biology, long-term recurrence, and survival.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-10121-y.

Transanal mesorectal excision: early outcomes in Australia and New Zealand

BACKGROUND

Transanal total mesorectal excision (taTME) aims to overcome some of the technical challenges faced when operating on mid and low rectal cancers. Specimen quality has been confirmed previously, but recent concerns have been raised about oncological safety. This multicentre prospective study aimed to evaluate the safety of taTME among early adopters in Australia and New Zealand.

METHODS

Data from all consecutive patients who had taTME for rectal cancer from July 2014 to February 2020 at six tertiary referral centres in Australasia were recorded and analysed.

RESULTS

A total of 308 patients of median age of 64 years underwent taTME. Some 75.6 per cent of patients were men, and the median BMI was 26.8 kg/m2. The median distance of tumour from anal verge was 7 cm. Neoadjuvant chemoradiotherapy was administered to 57.8 per cent of patients. The anastomotic leak rate was 8.1 per cent and there was no mortality within 30 days of surgery. Pathological examination found a complete mesorectum in 295 patients (95.8 per cent), a near-complete mesorectum in seven patients (2.3 per cent), and an incomplete mesorectum in six patients (1.9 per cent). The circumferential resection margin and distal resection margin was involved in nine patients (2.9 per cent), and two patients (0.6 per cent) respectively. Over a median follow-up of 22 months, the local recurrence rate was 1.9 per cent and median time to local recurrence was 30.5 months.

CONCLUSION

This study showed that, with appropriate training and supervision, skilled minimally invasive rectal cancer surgeons can perform taTME with similar pathological and oncological results to open and laparoscopic surgery.

Comparison of Survival between Single-Access and Conventional Laparoscopic Surgery in Rectal Cancer

Introduction

Innovative laparoscopic surgery for rectal cancer can be classified into 2 types: firstly, new instruments such as robotic surgery and secondly, new technique such as single-access laparoscopic surgery (SALS) and transanal total mesorectal excision (TaTME). Most reports of SALS for rectal cancer have shown pathologic outcomes comparable to those of conventional laparoscopic surgery (CLS); however, SALS is considered to be superior to CLS in terms of lower levels of discomfort and faster recovery rates. This study aimed to compare the survival outcomes of the two approaches.

Methods

From 2011 to 2014, 84 cases of adenocarcinoma of the rectum and anal canal were enrolled. The operations were anterior, low anterior, intersphincteric, and abdominoperineal resections. Data collected included postoperative outcomes. The oncological outcomes recorded included 3-year and 5-year survival, local recurrence, and metastasis.

Results

SALS was performed on 41 patients, and CLS was utilized in 43 cases. The demographic data of the two groups were similar. Intraoperative volumes of blood loss and conversion rates were similar, but operative time was longer in the SALS group. There were no significant differences in postoperative complications or pathological outcomes. The oncologic results were similar in terms of 3-year survival (100% and 97.7%; p = 1.00), 5-year survival (78.0% and 86.0%; p = 0.401), local recurrence rates (19.5% vs 11.6%, p = 0.376), and metastasis rates (19.5% vs 11.6%; p = 0.376) for SALS and CLS, respectively.

Conclusion

SALS and CLS for rectal and anal cancer had comparable pathological and survival results, but SALS showed some superior benefits in the early postoperative period.

Short-course radiotherapy with consolidation chemotherapy versus conventionally fractionated long-course chemoradiotherapy for locally advanced rectal cancer: randomized clinical trial

BACKGROUND

The trial hypothesis was that, in a resource-constrained situation, short-course radiotherapy would improve treatment compliance compared with conventional chemoradiotherapy for locally advanced rectal cancer, without compromising oncological outcomes.

METHODS

In this open-label RCT, patients with cT3, cT4 or node-positive non-metastatic rectal cancer were allocated randomly to 5 × 5 Gy radiotherapy and two cycles of XELOX (arm A) or chemoradiotherapy with concurrent capecitabine (arm B), followed by total mesorectal excision in both arms. All patients received a further six cycles of adjuvant chemotherapy with the XELOX regimen. The primary endpoint was treatment compliance, defined as the ability to complete planned treatment, including neoadjuvant radiochemotherapy, surgery, and adjuvant chemotherapy to a dose of six cycles.

RESULTS

Of 162 allocated patients, 140 were eligible for analysis: 69 in arm A and 71 in arm B. Compliance with planned treatment (primary endpoint) was greater in arm A (63 versus 41 per cent; P = 0.005). The incidence of acute toxicities of neoadjuvant therapy was similar (haematological: 28 versus 32 per cent, P = 0.533; gastrointestinal: 14 versus 21 per cent, P = 0.305; grade III-IV: 2 versus 4 per cent, P = 1.000). Delays in radiotherapy were less common in arm A (9 versus 45 per cent; P < 0.001), and overall times for completion of neoadjuvant treatment were shorter (P < 0.001). The rates of R0 resection (87 versus 90 per cent; P = 0.554), sphincter preservation (32 versus 35 per cent; P = 0.708), pathological complete response (12 versus 10 per cent; P = 0.740), and overall tumour downstaging (75 versus 75 per cent; P = 0.920) were similar. Downstaging of the primary tumour (ypT) was more common in arm A (P = 0.044). There was no difference in postoperative complications between trial arms (P = 0.838).

CONCLUSION

Reduced treatment delays and a higher rate of compliance were observed with treatment for short-course radiotherapy with consolidation chemotherapy, with no difference in early oncological surgical outcomes. In time- and resource-constrained rectal cancer units in developing countries, short-course radiotherapy should be the standard of care.

Total neoadjuvant therapy for locally advanced rectal cancer: the fuse is lit

Explosively disrupting

ESTRO/ACROP IORT recommendations for intraoperative radiation therapy in primary locally advanced rectal cancer

Carcinoma of the rectum is a heterogeneous disease. The clinical spectrum identifies a subset of patients with locally advanced tumours that are close to or involve adjoining structures, such as the sacrum, pelvic sidewalls, prostate or bladder. Within this group of patients categorized as "locally advanced", there is also variability in the extent of disease with no uniform definition of resectability. A practice-oriented definition of a locally advanced tumour is a tumour that cannot be resected without leaving microscopic or gross residual disease at the resection site. Since these patients do poorly with surgery alone, irradiation and chemotherapy have been added to improve the outcome. Intraoperative irradiation (IORT) is a component of local treatment intensification with favourable results in this subgroup of patients. International guidelines (National Comprehensive Cancer Network (NCCN) guidelines) currently recommend the use of IORT for rectal cancer resectable with very close or positive margins, especially for T4 and recurrent cancers. We report the ESTRO-ACROP (European Society for Radiotherapy and Oncology - Advisory Committee on Radiation Oncology Practice) recommendations for performing IORT in primary locally advanced rectal cancer.