Preoperative radiotherapy combined with total mesorectal excision for resectable rectal cancer: 12-year follow-up of the multicentre, randomised controlled TME trial

Expression of ZNF281 in colorectal cancer correlates with response to radiotherapy and survival

BACKGROUND

The treatment of Colorectal cancer (CRC) is extremely complex and survival rates vary depending on the stage of the disease at the time of diagnosis. Neoadjuvant chemoradiotherapy (NACRT), is the conventional treatment for locally advanced rectal cancer (LARC); however, the resistance to chemoradiotherapy in LARC is difficult to predict.

MATERIALS AND METHODS

In this study, clinical data of 126 LARC patients were collected and analyzed, and relevant validation was performed using GEO database and in vitro and in vivo experiments, including Western blotting and Real-time quantitative PCR, immunohistochemistry, immunofluorescence, clonogenic cell survival assays, and nude-mouse xenograft models.

RESULTS

In patients with LARC who were treated with neoadjuvant radiotherapy (NART), higher ZNF281 expression in malignant tissue was associated with a poorer prognosis and lesser degree of tumor regression. Cell and mouse experiments have shown that ZNF281 reduces the damage caused by X-rays to CRC cells and tumors grown in mice.

CONCLUSION

We found that the expression of ZNF281 predicted the radiation response of CRC cells and suggested the prognosis of patients with LARC who received neoadjuvant radiation therapy.

Comparing neoadjuvant therapy followed by local excision to total mesorectal excision in the treatment of early stage rectal cancer: a systematic review and meta-analysis of randomised clinical trials

INTRODUCTION

Total mesorectal excision (TME) is the standard-of-care in early, clinical stage (cT2-3 N0 M0) rectal cancer. Local excision (LE) may be an alternative after adequate response to neoadjuvant therapy (NAT), with either long-course chemoradiotherapy (nCRT) or short-course radiotherapy (SCRT), as a means of preserving the rectum and potentially obviating the morbidity of TME.

METHODS

A systematic review was performed according to PRISMA guidelines for studies that randomly assigned patients with cT2-3 N0 M0 rectal cancer to either NAT + LE or TME that reported radiologic, oncologic, surgical, and morbidity outcomes.

RESULTS

A total of 4 RCTs comprise 462 patients (232 patients receiving NAT + LE; nCRT n = 205; SCRT n = 27) and 230 undergoing TME, respectively. NAT compliance was 98.86%. The rate of early completion TME in the NAT + LE group was 22.3%, while the proportion of patients achieving durable organ preservation was 75.4% at mean follow-up of 5.6 years. There was no difference in disease-free survival (DFS) (HR [hazard ratio] 1.19; 95% CI 0.95, 1.49; p = 0.13) or overall survival (OS) (HR 0.94; 95% CI 0.72, 1.23; p = 0.63]) according to the assigned treatment arm. The local recurrence rate (LRR) (HR 1.22; 95% CI 0.5-3.02; p = 0.66) and distant metastases (HR 0.92; 95% CI 0.45, 1.90; p = 0.82) were also comparable between the groups. There was a significant reduction in major (OR 0.45; 95% CI 0.21, 0.95; p = 0.04) and minor morbidity (OR 0.45; 95% CI 0.24, 0.85; p = 0.01) for patients undergoing NAT + LE. Overall stoma formation was decreased in the NAT + LE group (OR 0.03; 95% CI 0.0, 0.23; p ≤ 0.00001).

CONCLUSION

NAT + LE reduces adverse effects of TME, without any compromise in oncological outcomes, and the potential for an organ preserving strategy should be discussed with patients with T2-3N0 rectal cancers prior to treatment.

Tumour-specific mesorectal excision for rectal cancer: Systematic review and meta-analysis of oncological and functional outcomes

BACKGROUND

Tumour-specific mesorectal excision (TSME) practice for rectal cancer only relies on small retrospective studies. This study aimed to perform a systematic review and meta-analysis to assess the oncological and functional outcomes of TSME practice.

METHODS

A systematic review protocol was drawn to include all the studies that compared partial versus total mesorectal excision (PME vs TME) practised for rectal adenocarcinoma up to 16 cm from the anal verge. A systematic literature search was conducted on EMBASE-Medline, Pubmed and Cochrane Library. Reports were screened for the study's outcomes: oncological radicality, postoperative anastomotic leak risk and functional outcomes. Included studies were appraised for risk-of-bias and meta-analysed. Evidence was rated with the GRADE approach.

RESULTS

Twenty-seven studies were included, consisting of 12325 patients (PME n = 4460, 36.2%; TME n = 7865, 63.8%). PME was performed for tumours higher than 10 cm from the anal verge in 54.5% of patients. There was no difference between PME and TME in circumferential resection margin positivity (OR 1.31, 95%CI 0.43-3.95, p = 0.64; I2 = 38%), and local recurrence risk (HR 1.05, 95%CI 0.52-2.10, p = 0.90; I2 = 40%). The postoperative leak risk (OR 0.42, 95%CI 0.27-0.67, p < 0.001; I2 = 60%) and the major low anterior resection syndrome risk (OR 0.34, 95%CI 0.28-0.40, p < 0.001; I2 = 0%) were lower after PME surgery. No difference was found in urinary incontinence (OR 0.68, 95%CI 0.13-3.67, p = 0.66) and urinary retention after early catheter removal (OR 2.00, 95%CI 0.24-16.51, p = 0.52).

CONCLUSIONS

Evidence from this meta-analysis shows that TSME for rectal cancer has good oncological results and leads to the best-fitted functional results possible for the patient's condition.

Complete response rates in rectal cancer: Temporal changes over a decade in a population-based nationwide cohort

INTRODUCTION

In the past decade many changes in neoadjuvant treatment for patients with rectal cancer have taken place and are expected to impact complete response rates. The aim of this study was to investigate the impact on pathological, and overall, complete response rates in a nationwide population-based cohort, in relation to changes in neoadjuvant treatment and the start of a Watch & Wait (WoW) study.

MATERIALS AND METHODS

A nationwide register study using prospectively collected data from the Swedish Colorectal Cancer Register between 2009 and 2020. Patients with rectal cancer stage I-III with a ypT0N0 in the resected specimen after neoadjuvant treatment and clinical complete responders from the yearly inclusion data of the national WoW study were included. Temporal changes in pathological and overall complete response rates were analysed, and differences in neoadjuvant treatment regimens over time and per region were studied.

RESULTS

Between 2009 and 2020 the pathological complete response rate for rectal cancer remained similar (Mann-Kendall tau of 0.091, p = 0.68) while the overall complete response rate increased significantly from 3.0% to 9.6% (Mann-Kendall tau of 0.818, p < 0.001). The pathological complete response rate for patients receiving short course radiotherapy followed by chemotherapy was reduced by 50% after the introduction of the WoW study.

CONCLUSIONS

During the studied time period the overall complete response rate increased significantly presumably due to changes in national neoadjuvant treatment regimens. Since the start of the national WoW study clinical complete response seem to partly replace pathological complete response.

Improving prognosis and assessing adjuvant chemotherapy benefit in locally advanced rectal cancer with deep learning for MRI: A retrospective, multi-cohort study

PURPOSE

Adjuvant therapy is recommended to minimize the risk of distant metastasis (DM) and local recurrence (LR) in patients with locally advanced rectal cancer (LARC). However, its role is controversial. We aimed to develop a pretreatment MRI-based deep learning model to predict LR, DM, and overall survival (OS) over 5 years after surgery and to identify patients benefitting from adjuvant chemotherapy (AC).

MATERIALS AND METHODS

The multi-survival tasks network (MuST) model was developed in a primary cohort (n = 308) and validated using two external cohorts (n = 247, 245). An AC decision tree integrating the MuST-DM score, perineural invasion (PNI), and preoperative carbohydrate antigen 19-9 (CA19-9) was constructed to assess chemotherapy benefits and aid personalized treatment of patients. We also quantified the prognostic improvement of the decision tree.

RESULTS

The MuST network demonstrated high prognostic accuracy in the primary and two external cohorts for the prediction of three different survival tasks. Within the stratified analysis and decision tree, patients with CA19-9 levels > 37 U/mL and high MuST-DM scores exhibited favorable chemotherapy efficacy. Similar results were observed in PNI-positive patients with low MuST-DM scores. PNI-negative patients with low MuST-DM scores exhibited poor chemotherapy efficacy. Based on the decision tree, 14 additional patients benefiting from AC and 391 patients who received over-treatment were identified in this retrospective study.

CONCLUSION

The MuST model accurately and non-invasively predicted OS, DM, and LR. A specific and direct tool linking chemotherapy decisions and benefit quantification has also been provided.

Reporting of Circumferential Resection Margin in Rectal Cancer Surgery

Importance

Circumferential resection margin (CRM) in rectal cancer surgery is a major prognostic indicator associated with local recurrence and overall survival. Facility rates of CRM positivity have recently been established as a new quality measure by the Commission on Cancer (CoC); however, the completeness of CRM status reporting is not well characterized.

Objective

To describe the changes in CRM reporting and factors associated with low rates of reporting.

Design, Setting, and Participants

A retrospective cohort study was conducted using data from the National Cancer Database between January 2010 and December 2019. Data were analyzed between October 1, 2021, and February 1, 2022. Data from the National Cancer Database included patients diagnosed with nonmetastatic rectal adenocarcinoma receiving surgical treatment at CoC-accredited facilities throughout the US.

Exposures

Patient, tumor, and facility-level factors. Facilities were divided by surgical volume, safety-net status, and CoC facility type.

Main Outcomes and Measures

Circumferential resection margin missingness rates.

Results

A total of 110 571 patients (59.3% men) with rectal adenocarcinoma who underwent curative-intent surgery at 1307 CoC-accredited hospitals were included for analysis. Reporting of CRM improved over the study period, with a mean (SE) missing 12.0% (0.32%) decreased from 16.3% (0.36%). Academic facilities had a higher missingness than other facility types (14.3% vs 10.5%-12.7%; P < .001). Mean (SE) rates of missingness were similar between hospitals of varying volume (lowest quartile: 12.2% [0.93%] vs highest quartile: 12.4% [0.53%]; P = .96). Cases in which fewer than 12 lymph nodes were removed had higher rates of missingness (18.1% vs 11.4%; P < .001). Increased odds of CRM missingness were noted with T category (odds ratio [OR], 1.50; 95% CI, 1.35-1.65) and N category (OR, 2.00; 95% CI, 1.82-2.20). Black race was associated with missingness (OR, 1.13; 95% CI, 1.06-1.14).

Conclusion and Relevance

Although CRM positivity reporting has improved over the last decade, the findings of this study suggest there is substantial room for improvement as it becomes a quality standard. Missingness appears to be associated with poor performance on other quality metrics and facility type. This measure appears to be ideal for targeted institution-level feedback to improve quality of care nationally.

A retrospective study analyzing if lymph node ratio carbon nanoparticles predict stage III rectal cancer recurrence

Background

Lymph node ratio has garnered increasing attention as a prognostic marker for rectal cancer; however, few studies have investigated the relationship between lymph node ratio and rectal cancer recurrence. Additionally, Carbon Nanoparticle tracking is a safe and effective strategy for locating tumors and tracking lymph nodes. However, no studies have reported the relationship between Carbon Nanoparticles and rectal cancer recurrence.

Methods

Patients with stage III rectal cancer who underwent radical resection between January 2016 and 2020 were analyzed. The primary outcome was tumor recurrence. 269 patients with stage III rectal cancer were included in this study. The effects of lymph node ratio, Carbon Nanoparticles, and other clinicopathological factors on rectal cancer recurrence were assessed using univariate, multivariate analyses and the t-test.

Results

Univariate analysis determined tumor recurrence using cytokeratin 19 fragment, CA-199, CEA, N-stage, positive lymph nodes, total lymph nodes, and lymph node ratio(positive/total); with the lymph node ratio being the most relevant. Receiver operating characteristic (ROC) analysis determined lymph node ratio =0.38 as the optimal cutoff value. The analysis of lymph node ratio ≥0.38 and <0.38 showed statistical differences in three indicators: tumor recurrence, CEA, and use of Carbon Nanoparticles.

Conclusion

Lymph node ratio is a strong predictor of stage III rectal cancer recurrence and may be considered for inclusion in future tumor-node-metastasis staging and stage III rectal cancer stratification. In addition, we found that Carbon Nanoparticles use significantly increased total lymph nodes and decreased lymph node ratio.

Molecular mechanisms in colitis-associated colorectal cancer

Sustained chronic inflammation of the large intestine leads to tissue damage and repair, which is associated with an increased incidence of colitis-associated colorectal cancer (CAC). The genetic makeup of CAC is somewhat similar to sporadic colorectal carcinoma (sCRC), but there are differences in the sequence and timing of alterations in the carcinogenesis process. Several models have been developed to explain the development of CAC, particularly the "field cancerization" model, which proposes that chronic inflammation accelerates mutagenesis and selects for the clonal expansion of phenotypically normal, pro-tumorigenic cells. In contrast, the "Big Bang" model posits that tumorigenic clones with multiple driver gene mutations emerge spontaneously. The details of CAC tumorigenesis-and how they differ from sCRC-are not yet fully understood. In this Review, we discuss recent genetic, epigenetic, and environmental findings related to CAC pathogenesis in the past five years, with a focus on unbiased, high-resolution genetic profiling of non-dysplastic field cancerization in the context of inflammatory bowel disease (IBD).

Radiomics Signature Based on Support Vector Machines for the Prediction of Pathological Complete Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

The objective of this study was to evaluate the discriminative capabilities of radiomics signatures derived from three distinct machine learning algorithms and to identify a robust radiomics signature capable of predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy in patients diagnosed with locally advanced rectal cancer (LARC). In a retrospective study, 211 LARC patients were consecutively enrolled and divided into a training cohort (n = 148) and a validation cohort (n = 63). From pretreatment contrast-enhanced planning CT images, a total of 851 radiomics features were extracted. Feature selection and radiomics score (Radscore) construction were performed using three different machine learning methods: least absolute shrinkage and selection operator (LASSO), random forest (RF) and support vector machine (SVM). The SVM-derived Radscore demonstrated a strong correlation with the pCR status, yielding area under the receiver operating characteristic curves (AUCs) of 0.880 and 0.830 in the training and validation cohorts, respectively, outperforming the RF and LASSO methods. Based on this, a nomogram was developed by combining the SVM-based Radscore with clinical indicators to predict pCR after neoadjuvant chemoradiotherapy. The nomogram exhibited superior predictive power, achieving AUCs of 0.910 and 0.866 in the training and validation cohorts, respectively. Calibration curves and decision curve analyses confirmed its appropriateness. The SVM-based Radscore demonstrated promising performance in predicting pCR for LARC patients. The machine learning-driven nomogram, which integrates the Radscore and clinical indicators, represents a valuable tool for predicting pCR in LARC patients.

Can the Single-stapling Technique Following Intersphincteric Resection with Transanal Total Mesorectal Excision Become the New Standard Anastomosis?

For transanal total mesorectal excision (TaTME), the indication for single-stapling technique (SST) has been expanded to include lower anastomosis, even in intersphincteric resection (ISR). We focused on the anastomotic techniques following ISR with TaTME and examined the feasibility and safety of the SST below the anorectal junction (ARJ). Data on postoperative anastomosis-related complications and anorectal function was evaluated in comparison to conventional manual hand-sewn coloanal anastomosis in ISR with TaTME. We examined patients with 3-6 cm tumors from the anal verge who underwent ISR with TaTME between January 2018 and March 2020, and whose anastomotic line was located below the ARJ. Postoperative short-term outcomes and anorectal functions were compared. We also analyzed the effects of various factors on major low anterior resection syndrome (LARS) using multivariate logistic regression analysis. In total, 87 patients-48 in the hand-sewn anastomosis group and 39 in the SST group-were included in this study. SST below the ARJ in ISR with TaTME did not exacerbate surgical outcomes, including anastomosis-related complications. The SST group had a significantly lower LARS score as compared to the hand-sewn anastomosis group, and the proportion of major LARS was significantly lower. Only hand-sewn anastomosis was identified as a statistically significant independent risk factor for major LARS. In TaTME, SST below the ARJ was safe and feasible and had a lower negative impact on postoperative anastomosis-related complications and anorectal function as compared to hand-sewn anastomosis. Thus, SST is a promising anastomotic option for patients with low-lying rectal tumors.

Impact of trans-anal versus laparoscopic total mesorectal excision on the surgical and pathologic outcomes of patients with rectal cancer: meta-analysis of randomized controlled trials

BACKGROUND

Despite its profound impact on the oncologic outcomes of rectal cancer, the most optimal surgical approach to total mesorectal excision (TME) has not been identified yet. All previous meta-analyses on this subject have been based on observational studies. This meta-analysis was conducted to assess the surgical and oncologic outcomes of laparoscopic TME (LaTME) compared to trans-anal TME (TaTME), utilizing only randomized controlled trials.

DESIGN

Systematic review and meta-analysis of randomized controlled trials.

METHODS

We searched electronic databases (MEDLINE, Cochrane CENTRAL, Clinicaltials.gov) from 2010 onwards, for all published clinical trials comparing TaTME to LaTME. Results are presented as risk ratios, with 95% CI, and pooled using the random effects model.

RESULTS

A total of 1691 patients, from 6 eligible randomized controlled trials, were included for analysis. Analyzed data showed no significant difference in morbidity (RR: 0.85, p = 0.15), mortality (RR: 0.50, p = 0.44), conversion to open (RR: 0.40, p = 0.07), or anastomotic leakage (RR: 0.73, p = 0.10) between TaTME and LaTME. There was also no difference in the rate of positive distal resection margin (DRM) (RR: 0.55, p = 0.10) or positive circumferential resection margin (CRM) (RR: 0.67, p = 0.30). Patients undergoing TaTME were more likely to have a complete TME (RR: 1.06, p = 0.002) and shorter hospital stays (RR: - 0.97, p < 0.00001).

CONCLUSIONS

Patients undergoing TaTME for rectal cancer were more likely to have a complete TME when compared to LaTME, though this did not translate into improved distal or circumferential resection margin. Additionally, TaTME and LaTME had similar surgical outcomes except for shorter length of stay with TaTME.

Survival outcomes in locally advanced dMMR rectal cancer: surgery plus adjunctive treatment vs. surgery alone

BACKGROUND

Recent studies have shown that deficient mismatch repair (dMMR) rectal cancer may be related to treatment resistance, resulting in a worse prognosis than proficient MMR (pMMR) rectal cancer. The purpose of this study was to explore whether surgery plus other treatments (radiotherapy and chemotherapy) can bring more benefits to these patients than surgery alone.

METHODS

A retrospective study of 168 patients with rectal adenocarcinoma who underwent total mesorectal excision was conducted using immunohistochemical methods to determine MMR status and a propensity score matching model to minimize potential confounding factors between subgroups of patients with different treatment regimens. Kaplan-Meier analysis, log-rank tests, and Cox regression models were used to assess overall survival (OS) and disease-free survival (DFS) in patient subgroups.

RESULTS

Only 6.9% (n = 168) of patients in the total cohort had dMMR rectal adenocarcinoma, and the most common cause of dMMR was a PMS2 deletion (103, 61.3%). The median DFS of the surgery alone group was 45.7 months (IQR, 40.9 to 77.8), and the median DFS of the surgery plus other treatment group was 43.9 months (IQR, 14.2 to 80.1). The surgery alone group was superior to the surgery plus other treatment group (HR, 0.16; 95% CI, 0.07 to 0.38; p = 0.005). There was no significant difference in OS (45.8 (IQR, 41.0 to 79.8) vs. 45.9 (IQR, 38.5 to 80.3)) between the two groups (HR, 0.57; 95% CI, 0.23 to 1.40; p = 0.263).

CONCLUSIONS

For patients with locally advanced dMMR rectal adenocarcinoma, compared with surgery alone, surgery plus other treatment options (radiotherapy and chemotherapy) do not grant long-term survival benefits but rather shorten DFS.

Optimization of therapeutic strategies for selective lateral lymph node dissection after neoadjuvant chemoradiotherapy in patients with rectal cancer with clinical suspected lateral lymph node metastasis

Background

Selective lateral lymph node (LLN) dissection with total mesorectal excision after neoadjuvant chemoradiotherapy (nCRT) is pointed out to reduce lateral compartment recurrence and to improve survival in patients with rectal cancer with LLN metastases. This study aimed to explore the safety, surgical indications, and survival outcomes of LLN dissection after nCRT.

Methods

This multicenter retrospective study included patients with rectal cancer with clinical evidence of LLN metastases (n = 466) treated across three hospitals in China. Patients who underwent total mesorectal excision and LLN dissection were grouped into nCRT (n = 155) and non-nCRT (n = 291), respectively. Propensity score matching was used to minimize selection bias.

Results

After matching, nCRT did not significantly increase the surgery duration, intraoperative blood loss or postoperative complications (P > 0.05). In a multivariate logistic regression analysis, poor/mucinous/signet adenocarcinoma (P = 0.042) and post-nCRT LLN short diameter ≥7 mm (P < 0.001) were independent risk factors for pathological LLN metastasis after nCRT. Overall survival (P < 0.001) and disease-free survival (P < 0.001) were significantly worse in patients with LLN metastasis, which was, however, not an independent risk factor for survival after eliminating confounders. Multivariate prognostic analysis of 40-patient subset with pathological LLN metastasis showed that distant metastasis, metastasis beyond the obturator or internal iliac region, and ≥2 LLN metastasis were independent predictors of poor overall survival.

Conclusions

Selective LLN dissection after nCRT is safe and feasible with acceptable perioperative outcomes. Patients with a post-nCRT LLN short diameter ≥7 mm or poor/mucinous/signet adenocarcinoma should receive supplementary LLN dissection after nCRT. However, patients with distant metastasis, metastasis beyond the obturator or internal iliac region, and involvement of ≥2 LLN may not benefit from LLN dissection, and LLN dissection should be carefully considered in such patients.

Towards deep-learning (DL) based fully automated target delineation for rectal cancer neoadjuvant radiotherapy using a divide-and-conquer strategy: a study with multicenter blind and randomized validation

PURPOSE

Manual clinical target volume (CTV) and gross tumor volume (GTV) delineation for rectal cancer neoadjuvant radiotherapy is pivotal but labor-intensive. This study aims to propose a deep learning (DL)-based workflow towards fully automated clinical target volume (CTV) and gross tumor volume (GTV) delineation for rectal cancer neoadjuvant radiotherapy.

MATERIALS & METHODS

We retrospectively included 141 patients with Stage II-III mid-low rectal cancer and randomly grouped them into training (n = 121) and testing (n = 20) cohorts. We adopted a divide-and-conquer strategy to address CTV and GTV segmentation using two separate DL models with DpuUnet as backend-one model for CTV segmentation in the CT domain, and the other for GTV in the MRI domain. The workflow was validated using a three-level multicenter-involved blind and randomized evaluation scheme. Dice similarity coefficient (DSC) and 95th percentile Hausdorff distance (95HD) metrics were calculated in Level 1, four-grade expert scoring was performed in Level 2, and head-to-head Turing test in Level 3.

RESULTS

For the DL-based CTV contours over the testing cohort, the DSC and 95HD (mean ± SD) were 0.85 ± 0.06 and 7.75 ± 6.42 mm respectively, and 96.4% cases achieved clinical viable scores (≥ 2). The positive rate in the Turing test was 52.3%. For GTV, the DSC and 95HD were 0.87 ± 0.07 and 4.07 ± 1.67 mm respectively, and 100% of the DL-based contours achieved clinical viable scores (≥ 2). The positive rate in the Turing test was 52.0%.

CONCLUSION

The proposed DL-based workflow exhibited promising accuracy and excellent clinical viability towards automated CTV and GTV delineation for rectal cancer neoadjuvant radiotherapy.

An MRI-based scoring system for pretreatment risk stratification in locally advanced rectal cancer

BACKGROUND

Accurately assessing the risk of recurrence in patients with locally advanced rectal cancer (LARC) before treatment is important for the development of treatment strategies. The purpose of this study is to develop an MRI-based scoring system to predict the risk of recurrence in patients with LARC.

METHODS

This was a multicenter observational study that enrolled participants who underwent neoadjuvant chemoradiotherapy. To evaluate the risk of recurrence in these patients, we developed the mrDEC scoring system and assessed inter-reader agreement. Additionally, we plotted Kaplan-Meier curves to compare the 3-year disease-free survival (DFS) and 5-year overall survival (OS) rates among patients with different mrDEC scores.

RESULTS

A total of 1287 patients with LARC were included in this study. We observed substantial inter-reader agreement for mrDEC. Based on the mrDEC scores ranging from 0 to 3, the patients were categorized into four groups. The 3-year DFS rates for the groups were 91.0%, 79.5%, 65.5%, and 44.0% (P < 0.0001), respectively, and the 5-year OS rates were 92.9%, 87.1%, 74.8%, and 44.5%, respectively (P < 0.0001).

CONCLUSIONS

The mrDEC scoring system proved to be an effective tool for predicting the prognosis of patients with LARC and can assist clinicians in clinical decision-making.

The Incidence and Prognosis Value of Perineural Invasion in Rectal Carcinoma: From Meta-Analyses and Real-World Clinical Pathological Features

AIMS

Perineural invasion (PNI) is a special type of metastasis of several cancers and has been reported as being a factor for poor prognosis in colorectal carcinoma. However, investigations of PNI in only rectal cancer and a comprehensive analysis combining meta-analyses with real-world case studies remain lacking.

MATERIALS AND METHODS

First, articles from 2000 to 2020 concerning the relationship between PNI and rectal cancer prognoses and clinical features were meta-analysed. Subsequently, we carried out a retrospective analysis of 312 rectal cancer cases that underwent radical surgery in the real world. The incidence of PNI and the relationship between PNI and prognosis, as well as clinicopathological factors, were investigated.

RESULTS

The incidence of PNI was 23.09% and 33.01% in the meta-analysis and clinical cases, respectively. PNI occurred as early as stage I (2.94%). Moreover, neoadjuvant therapy significantly reduced the PNI-positive rate (20.34% versus 26.54%). Both meta-analysis and real-world clinical case studies suggested that PNI-positive patients had poorer prognoses than PNI-negative patients. We established an effective risk model consisting of T stage, differentiation and lymphovascular invasion to predict PNI in rectal cancer.

CONCLUSION

PNI is a poor prognostic factor for rectal cancer and could occur even in stage I. Additionally, neoadjuvant therapy could sufficiently reduce the PNI-positive rate. T stage, lymphovascular invasion and differentiation grade were independent risk factors for PNI and the risk model that included these factors could predict the probability of PNI.

ATR-binding lncRNA ScaRNA2 promotes cancer resistance through facilitating efficient DNA end resection during homologous recombination repair

BACKGROUND

Our previous study first showed that ATR-binding long noncoding RNA (lncRNA) is necessary for ATR function and promotes cancer resistance. However, the specific lncRNAs instrumental in ATR activation remain largely unclear, which limits our comprehensive understanding of this critical biological process.

METHODS

RNA immunoprecipitation (RIP) followed by RNA sequencing was employed to identify ATR-binding lncRNAs, which were further validated using RIP-qPCR assays. Immunofluorescence staining and Western blotting were applied to detect the activation of DNA damage repair factors. After the effect of scaRNA2 on cellular sensitivity to DNA-damaging reagents was determined, the effects of scaRNA2 on radiotherapy were investigated in patient-derived organoids and xenograft preclinical models. The clinical relevance of scaRNA2 was also validated in tissues isolated from rectal cancer patients.

RESULTS

ScaRNA2 was identified as the most enriched ATR-binding lncRNA and was found to be essential for homologous recombination (HR) mediated DNA damage repair. Furthermore, scaRNA2 knockdown abrogated the recruitment of ATR and its substrates in response to DNA damage. Mechanistically, scaRNA2 was observed to be necessary for Exo1-mediated DNA end resection and bridged the MRN complex to ATR activation. Knockdown of scaRNA2 effectively increased the sensitivity of cancer cells to multiple kinds of DNA damage-related chemoradiotherapy. Preclinically, knockdown of scaRNA2 improved the effects of radiotherapy on patient-derived organoids and xenograft models. Finally, an increase in scaRNA2 colocalized with ATR was also found in clinical patients who were resistant to radiotherapy.

CONCLUSIONS

ScaRNA2 was identified as the most abundant lncRNA bound to ATR and was demonstrated to bridge DNA end resection to ATR activation; thus, it could be applied as a potent target for combined cancer treatments with chemoradiotherapy.

The benefits of adjuvant chemotherapy are associated with the kind of neoadjuvant therapy in stage ypI rectal cancer: evidence based on population analysis

PURPOSE

The oncological role of adjuvant chemotherapy (ACT) remains debated in locally advanced rectal cancer (RC) after neoadjuvant therapy (NAT), especially ypI RC. In this study, we used population-based data to evaluate the benefits of ACT in stage ypI RC after NAT and surgery. Moreover, we tried to differentiate what kind of NAT (radiotherapy alone or chemoradiotherapy) was administered because this may affect the further efficacy of ACT.

METHODS

All patients with stage ypI primary rectal malignancy were diagnosed in the SEER database between 2004 and 2017. The Kaplan-Meier method was applied to estimate the effects of ACT in survival analysis. Cox regression was performed to calculate the hazard ratio (HR) and the prognosis factors of survival. Propensity score matching (PSM) was used to balance the parameters between therapy groups.

RESULTS

The overall cohort's median follow-up time was 105 months. For 5-year OS and CSS, there were no significant differences between the ACT ( +) and ACT (-) groups (p = 0.105; p = 0.788). However, subgroup analyses according to the kind of NAT found that ACT improved overall survival (OS) and cancer-specific survival (CSS) in patients who received neoadjuvant radiotherapy (nRT) (p < 0.001, p = 0.015). Among patients who received neoadjuvant chemoradiotherapy (nCRT), no significant survival benefits were found between the ACT ( +) and ACT (-) groups (p = 0.526, p = 0.288).

CONCLUSION

Our population-based cohort study suggested that the efficacy of ACT was associated with the kind of NAT. The ACT provides survival benefits in stage ypI RC for patients who received nRT. However, among patients who received nCRT, ACT did not improve long-term survival.

Low Anterior Resection Syndrome (LARS) after Surgery for Rectal Cancer: An Inevitable Price to Pay for Survival, or a Preventable Complication?

BACKGROUND

Rectal cancer is frequent and often treated with sphincter-saving procedures that may cause LARS, a syndrome characterized by symptoms of bowel disfunction that may severely affect quality of life. LARS is common, but its pathogenesis is mostly unknown. The aim of this study is to assess the incidence of LARS and to identify potential risk factors.

METHODS

We performed an observational retrospective single center analysis. The following data were collected and analyzed for each patient: demographics, tumor-related data, and intra- and peri-operative data. Statistical analysis was conducted, including descriptive statistics and multivariate logistic regression to identify independent risk factors.

RESULTS

Total LARS incidence was 31%. Statistically significant differences were found in tumor distance from anal verge, tumor extension (pT and diameter) and tumor grading (G). Multivariate analysis identified tumor distance from anal verge and tumor extension as an independent predictive factor for both major and total LARS. Adjuvant therapy, although not significant at univariate analysis, was identified as an independent predictive factor. Time to stoma closure within 10 weeks seems to reduce incidence of major LARS.

CONCLUSIONS

bold LARS affects a considerable portion of patients. This study identified potential predictive factors that could be useful to identify high risk patients for LARS.

Genomic-driven nutritional interventions for radiotherapy-resistant rectal cancer patient

Radiotherapy response of rectal cancer patients is dependent on a myriad of molecular mechanisms including response to stress, cell death, and cell metabolism. Modulation of lipid metabolism emerges as a unique strategy to improve radiotherapy outcomes due to its accessibility by bioactive molecules within foods. Even though a few radioresponse modulators have been identified using experimental techniques, trying to experimentally identify all potential modulators is intractable. Here we introduce a machine learning (ML) approach to interrogate the space of bioactive molecules within food for potential modulators of radiotherapy response and provide phytochemically-enriched recipes that encapsulate the benefits of discovered radiotherapy modulators. Potential radioresponse modulators were identified using a genomic-driven network ML approach, metric learning and domain knowledge. Then, recipes from the Recipe1M database were optimized to provide ingredient substitutions maximizing the number of predicted modulators whilst preserving the recipe's culinary attributes. This work provides a pipeline for the design of genomic-driven nutritional interventions to improve outcomes of rectal cancer patients undergoing radiotherapy.

Predicting the risk of distant metastasis in patients with locally advanced rectal cancer using model based on pre-treatment T2WI-based radiomic features plus postoperative pathological stage

Objective

To assess the prognostic value of a model based on pre-treatment T2WI-based radiomic features and postoperative pathological staging in patients with locally advanced rectal cancer who have undergone neoadjuvant chemoradiotherapy.

Methods

Radiomic features were derived from T2WI, and a radiomic signature (RS) was established and validated for the prediction of distant metastases (DM). Subsequently, we designed and validated a nomogram model that combined the radiomic signature and postoperative pathological staging for enhanced DM prediction. Performance measures such as the concordance index (C-index) and area under the curve (AUC) were computed to assess the predictive accuracy of the models.

Results

A total of 260 patients participated in this study, of whom 197 (75.8%) were male, and the mean age was 57.2 years with a standard deviation of 11.2 years. 15 radiomic features were selected to define the radiomic signature. Patients with a high-risk radiomic signature demonstrated significantly shorter distant metastasis-free survival (DMFS) in both the development and validation cohorts. A nomogram, incorporating the radiomic signature, pathological T stage, and N stage, achieved an area under the curve (AUC) value of 0.72 (95% CI, 0.60-0.83) in the development cohort and 0.83 (95% CI, 0.73-0.92) in the validation cohort.

Conclusion

A radiomic signature derived from T2WI-based radiomic features can effectively distinguish patients with varying risks of DM. Furthermore, a nomogram integrating the radiomic signature and postoperative pathological stage proves to be a robust predictor of DMFS.

Total neoadjuvant therapy versus standard neoadjuvant treatment strategies for the management of locally advanced rectal cancer: network meta-analysis of randomized clinical trials

BACKGROUND

This study compared the advantages and disadvantages of total neoadjuvant therapy (TNT) strategies for patients with locally advanced rectal cancer, compared with the more traditional multimodal neoadjuvant management strategies of long-course chemoradiotherapy (LCRT) or short-course radiotherapy (SCRT).

METHODS

A systematic review and network meta-analysis of exclusively RCTs was undertaken, comparing survival, recurrence, pathological, radiological, and oncological outcomes. The last date of the search was 14 December 2022.

RESULTS

In total, 15 RCTs involving 4602 patients with locally advanced rectal cancer, conducted between 2004 and 2022, were included. TNT improved overall survival compared with LCRT (HR 0.73, 95 per cent credible interval 0.60 to 0.92) and SCRT (HR 0.67, 0.47 to 0.95). TNT also improved rates of distant metastasis compared with LCRT (HR 0.81, 0.69 to 0.97). Reduced overall recurrence was observed for TNT compared with LCRT (HR 0.87, 0.76 to 0.99). TNT showed an improved pCR compared with both LCRT (risk ratio (RR) 1.60, 1.36 to 1.90) and SCRT (RR 11.32, 5.00 to 30.73). TNT also showed an improvement in cCR compared with LCRT (RR 1.68, 1.08 to 2.64). There was no difference between treatments in disease-free survival, local recurrence, R0 resection, treatment toxicity or treatment compliance.

CONCLUSION

This study provides further evidence that TNT has improved survival and recurrence benefits compared with current standards of care, and may increase the number of patients suitable for organ preservation, without negatively influencing treatment toxicity or compliance.

Implication of MRI Risk Stratification System on the Survival Benefits of Adjuvant Chemotherapy After Neoadjuvant Chemoradiotherapy in Patients With Locally Advanced Rectal Cancer

RATIONALE AND OBJECTIVES

To investigate the implication of a Magnetic resonance imaging (MRI) risk stratification system on the selection of patients with locally advanced rectal cancer (LARC) who can benefit from adjuvant chemotherapy (ACT) after neoadjuvant chemoradiotherapy (NCRT).

MATERIALS AND METHODS

This retrospective study included 328 patients with LARC who underwent NCRT and surgery. The median follow-up duration was 79 months (Interquartile range, 66-94 months). Cox logistic regression analysis was used to identify MRI risk factors and develop a risk stratification system to stratify patients into groups with high and low risks. Kaplan-Meier curves of distant metastasis-free survival (DMFS) and overall survival (OS) were used to show the benefits of ACT and stratify results based on the MRI risk stratification system and postoperative pathological staging.

RESULTS

An MRI risk stratification system was built based on four MRI risk factors, including MRI-identified T3b-T4 stage, N1-N2 stage, extramural venous invasion, and tumor deposits. 74 (22.6%) patients with 3-4 MRI risk factors were classified into the MRI high-risk group. ACT could significantly improve 5-year DMFS (19.2% versus 52.1%; p < 0.001) and OS (34.6% versus 75.0%; p < 0.001) for patients in the MRI high-risk group, while ACT had no survival benefit for patients in the MRI low-risk group. The benefits of ACT were not observed in patients with any pathological staging subgroups (ypT0-2N0, ypT3-4N0, and ypN+).

CONCLUSION

Patients in the MRI high-risk group could benefit from ACT, regardless of postoperative pathological staging. Baseline MRI should be considered more in ACT decision-making.

Construction and Evaluation of Nomogram for Hematological Indicators to Predict Pathological Response after Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

OBJECTIVE

A retrospective study was conducted by developing prediction models to evaluate the association between hematological indexes, their changes during neoadjuvant chemoradiotherapy (NCRT), and tumor pathological response in patients with locally advanced rectal cancer.

METHODS

The clinical data of 202 patients who received NCRT and radical surgery in Sichuan Cancer Hospital were retrospectively analyzed. Univariate and logistic multivariate regression analyses were used to identify hematological indexes with predictive significance. The independent risk factors were imported into the R software, and a nomogram prediction model was developed. The bootstrap method and ROC curve were used to evaluate the discriminative degree of the model.

RESULTS

Univariate analysis demonstrated age, tumor diameter, preoperative T, distance from tumor to the anal verge, CEA before NCRT, preoperative CEA, lymphocyte changes, platelet changes, and pathology of rectal cancer after NCRT were associated. Multivariate analysis demonstrated that age, tumor distance from the anus, preoperative CEA, lymphocyte changes, and platelet changes were independent risk factors. The independent risk factors were imported into the R software to construct a nomogram model. The area under the ROC was 0.76, and the slope of the calibration curve of the nomogram was close to 1.

CONCLUSION

A low preoperative CEA level, a young age, a high tumor from the anal verge, the maintenance of circulating lymphocyte level, and a decreased platelet level after NCRT are important factors for favorable outcomes after NCRT. Developing a nomogram prediction model with good discrimination and consistency can provide some guidance for predicting pathological responses after NCRT.

Adjuvant chemotherapy in locally advanced rectal cancer after neo-adjuvant concurrent chemoradiotherapy and surgery: A retrospective study in Vietnamese patients

Background

Advances in preoperative chemoradiotherapy and surgical techniques offered improvements in rates of locoregional recurrence but did not address distant metastasis. Traditionally, adjuvant chemotherapy has been administered with the goal of limiting systemic recurrences.

Objective

Evaluation of the efficacy and safety of adjuvant chemotherapy in patients with locally advanced rectal cancer after preoperative chemoradiotherapy and surgery.

Methods

From January 2017 to December 2018, 103 patients diagnosed with clinical stage II or III rectal cancer received adjuvant chemotherapy with capecitabine or XELOX regimens after neoadjuvant concurrent chemoradiotherapy and total mesorectal excision. Overall survival, disease-free survival, and toxicity were analyzed.

Results

The median follow-up time was 52.5 months (6.5-66.8 months). The mean 3-year disease-free survival and 3-year overall survival were 86.2% (95% CI: 82.8-89.6) and 92.2% (95% CI: 86.9-97.5), respectively. The rate of hematologic and nonhematologic toxicity was low, mostly grades 1 and 2 including anemia, leucopenia, thrombocytopenia, and liver enzymes elevations were 85.4, 50.5, 42.8, and 45.6%, respectively.

Conclusion

The capecitabine and XELOX regimen in adjuvant settings for rectal cancer patients receiving neoadjuvant chemoradiotherapy and surgery was a safe and effective modality. Further randomized trials need to be conducted to evaluate the role of postoperative therapy for these individuals.

IMMUNOREACT 0: Biopsy-based immune biomarkers as predictors of response to neoadjuvant therapy for rectal cancer-A systematic review and meta-analysis

BACKGROUND

The main therapy for rectal cancer patients is neoadjuvant therapy (NT) followed by surgery. Immune biomarkers are emerging as potential predictors of the response to NT. We performed a meta-analysis to estimate their predictive significance.

METHODS

A systematic literature search of PubMed, Ovid MEDLINE and EMBASE databases was performed to identify eligible studies. Studies on patients with rectal cancer undergoing NT in which the predictive significance of at least one of the immunological markers of interest was assessed by immunohistochemistry (IHC) in pretreatment biopsies were included.

RESULTS

Seventeen studies reporting sufficient data met the inclusion criteria for meta-analysis. High levels of total CD3+, CD4+ and CD8+ tumor infiltrating lymphocytes (TILs), as well as stromal and intraepithelial CD8+ compartments, significantly predicted good pathological response to NT. Moreover, high levels of total (tumoral and immune cell expression) PD-L1 resulted associated to a good pathological response. On the contrary, high levels of intraepithelial CD4+ TILs were correlated with poor pathological response. FoxP3+ TILs, tumoral PD-L1 and CTLA-4 were not correlated to the treatment response.

CONCLUSION

This meta-analysis indicated that high-density TILs might be predictive biomarkers of pathological response in patients that underwent NT for rectal cancer.

Neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy alone for patients with locally advanced rectal cancer: a propensity-score-matched analysis combined with SEER validation

BACKGROUND

Neoadjuvant therapy followed by radical surgery is recommended for locally advanced rectal cancer (LARC). But radiotherapy can cause potential adverse effects. The therapeutic outcomes, postoperative survival and relapse rates between neoadjuvant chemotherapy (N-CT) and neoadjuvant chemoradiotherapy (N-CRT) patients have rarely been studied.

METHODS

From February 2012 to April 2015, patients with LARC who underwent N-CT or N-CRT followed by radical surgery at our center were included. Pathologic response, surgical outcomes, postoperative complications and survival outcomes (including overall survival [OS], disease-free survival [DFS], cancer-specific survival [CSS] and locoregional recurrence-free survival [LRFS]) were analyzed and compared. Concurrently, the Surveillance, Epidemiology, and End Results Program (SEER) database was used to compare OS in an external source.

RESULTS

A total of 256 patients were input into the propensity score-matching (PSM) analysis, and 104 pairs remained after PSM. After PSM, the baseline data were well matched and there was a significantly lower tumor regression grade (TRG) (P < 0.001), more postoperative complications (P = 0.009) (especially anastomotic fistula, P = 0.003) and a longer median hospital stay (P = 0.049) in the N-CRT group than in the N-CT group. No significant difference was observed in OS (P = 0.737), DFS (P = 0.580), CSS (P = 0.920) or LRFS (P = 0.086) between the N-CRT group and the N-CT group. In the SEER database, patients who received N-CT had similar OS in both TNM II (P = 0.315) and TNM III stages (P = 0.090) as those who received N-CRT.

CONCLUSION

N-CT conferred similar survival benefits but caused fewer complications than N-CRT. Thus, it could be an alternative treatment of LARC.

Preoperative Radiotherapy Decision-Tree for Rectal Cancer Patients: A Real-World Analysis Based on the Swedish Colorectal Cancer Registry

BACKGROUND

There are 3 widely used preoperative radiotherapy (RT) procedures in rectal cancer treatment including long-course RT (LRT), short-course RT with delayed surgery (SRTW), and short-course RT with immediate surgery (SRT). However, further evidence is required to determine which treatment option results in more optimal patient survival.

METHODS

This Swedish Colorectal Cancer Registry-based retrospective study of real-world data included 7766 stage I-III rectal cancer patients, of which 2982, 1089, 763, and 2932 patients received no RT (NRT), LRT, SRTW, and SRT, respectively. The Kaplan-Meier survival curve and Cox proportional hazard multivariate model were used to identify potential risk factors and to examine the independent association of RT with patient survival after adjusting for baseline confounding factors.

RESULTS

RT effects on survival differed by age and clinical T stage (cT) subgroups. Subsequent survival analysis by age and cT subgroups confirmed that patients ≥70 years old with cT4 benefited from any RT (P < .001, NRT as reference) and equally from any RT (P > .05 pairwise between RTs). In contrast, for cT3 patients ≥70 years, SRT and LRT were associated with better survival than SRTW (P < .001). In patients <70 years, LRT and SRTW had superior survival benefits in cT4 patients but inferior to SRT (P < .001); SRT was the only effective treatment in the cT3N+ subgroup (P = .032); patients with cT3N0 and <70 years did not benefit from any RT.

CONCLUSION

This study suggests that preoperative RT strategies may have varying effects on the survival of rectal cancer patients, depending on their age and clinical stage.

Treatment stratification and prognosis assessment using circulating tumor DNA in locally advanced rectal cancer: A systematic review and meta-analysis

BACKGROUND

Circulating tumor DNA (ctDNA) is an emerging biomarker for locally advanced rectal cancer (LARC), giving hope for stratified treatment. As the completed studies have small sample sizes and different experimental methods, systematic review and meta-analysis were performed to explore their role in predicting pathological complete response (pCR), tumor recurrence, and prognosis.

METHODS

PubMed, Embase, and the Web of Science were searched for potentially eligible studies published up to September 6, 2022. Pooled relative risk (RR) was calculated to predict pCR and tumor recurrence, and pooled hazard ratio (HR) was calculated to evaluate the prognosis of overall survival (OS), recurrence-free survival (RFS), and metastasis-free survival (MRS).

RESULTS

Twelve studies published between 2018 and 2022 included 931 patients, and 2544 serum samples were eventually included in the meta-analysis. The pooled revealed that ctDNA-negative patients were more likely to have a pCR (RR = 1.64, 95% confidence interval [CI]: 1.26-2.12). The pooled revealed that ctDNA-positive patients were at high risk of recurrence (RR = 3.37, 95% CI: 2.34-4.85) and had a poorer prognosis for OS (HR = 3.03, 95% CI: 1.86-4.95), RFS (HR = 7.08, 95% CI: 4.12-12.14), and MRS (HR = 2.77, 95% CI: 2.01-3.83).

CONCLUSION

ctDNA may be useful for stratifying treatment and assessing prognosis in patients with LARC, but its clinical application still needs to be confirmed in a prospective multicenter study with large samples.

Report from the 24th Annual Western Canadian Gastrointestinal Cancer Consensus Conference on Colorectal Cancer, Richmond, British Columbia, 28-29, October 2022

The 24th annual Western Canadian Gastrointestinal Cancer Consensus Conference (WCGCCC) was held in Richmond, British Columbia, on 28-29 October 2022. The WCGCCC is an interactive multidisciplinary conference attended by healthcare professionals from across Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals such as dieticians, nurses and a genetic counsellor participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer.

Adjuvant chemotherapy improves long-term survival in pathologic stage III rectal mucinous adenocarcinoma after pre-operative chemoradiotherapy

PURPOSE

The benefits of adjuvant chemotherapy remain debated rectal mucinous adenocarcinoma (MC). Our study aims to delve into the efficacy of adjuvant chemotherapy in pathologic stage III rectal MC by a large population-based database.

METHODS

The Chi-square test was performed to examine the parameters between treatment groups. The overall survival (OS) and cancer-specific survival (CSS) of treatment groups were conducted by using the Kaplan-Meier method. The impact of factors on survival was assessed using Cox regression analyses. To balance the covariates and reduce the selection bias, we employed propensity score matching (PSM) to narrow the differences between treatment groups.

RESULTS

The median follow-up time for overall patients was 80 months. In the pre-operative chemoradiotherapy (pre-CRT) group, patients who received adjuvant chemotherapy had significantly better 5-year OS and CSS. Multivariate analyses found that adjuvant chemotherapy was associated with better OS (p < 0.001, HR (95% CI): 0.66 (0.51-0.86)) and CSS (p = 0.012, HR (95% CI): 0.71 (0.54-0.93)). However, adjuvant chemotherapy was not an independent prognosis factor in both OS (p = 0.149, HR (95% CI): 0.76 (0.53-1.1); Supplement Table 1) and CSS (p = 0.183, HR (95% CI): 0.74 (0.48-1.15)) in patients who did not receive pre-CRT. After PSM, similar results were found in the pre-CRT and the no pre-CRT groups.

CONCLUSION

In conclusion, our population-based retrospective cohort study indicates that the effects of adjuvant chemotherapy were associated with the pre-CRT status in patients with stage III rectal MC. In patients who underwent pre-CRT, the receipt of adjuvant chemotherapy was associated with better survival outcomes. Conversely, adjuvant chemotherapy does not seem to confer significant survival benefits to patients without pre-CRT.

International Society of University Colon and Rectal Surgeons survey of surgeons' preference on rectal cancer treatment

PURPOSE

Rectal cancer treatment has a wide range of possible approaches from radical extirpative surgery to nonoperative watchful waiting following chemoradiotherapy, with or without, additional chemotherapy. Our goal was to assess the personal opinion of active practicing surgeons on rectal cancer treatment if he/she was the patient.

METHODS

A panel of the International Society of University Colon and Rectal Surgeons (ISUCRS) selected 10 questions that were included in a questionnaire that included other items including demographics. The questionnaire was distributed electronically to ISUCRS fellows and other surgeons included in our database and remained open from April 16 to 28, 2020.

RESULTS

One hundred sixty-three specialists completed the survey. The majority of surgeons (n=65, 39.9%) chose the minimally invasive (laparoscopic) surgery for their personal treatment of rectal cancer. For low-lying rectal cancer T1 and T2, the treatment choice was standard chemoradiation+local excision (n=60, 36.8%) followed by local excision±chemoradiotherapy if needed (n=55, 33.7%). In regards to locally advanced low rectal cancer T3 or greater, the preference of the responders was for laparoscopic surgery (n=65, 39.9%). We found a statistically significant relationship between surgeons' age and their preference for minimally invasive techniques demonstrating an age-based bias on senior surgeons' inclination toward open approach.

CONCLUSION

Our survey reveals an age-based preference by surgeons for minimally invasive surgical techniques as well as organ-preserving techniques for personal treatment of treating rectal cancer. Only 1/4 of specialists do adhere to the international guidelines for treating early rectal cancer.

ADT-OH synergistically enhanced the antitumor activity of celecoxib in human colorectal cancer cells

BACKGROUND

Colorectal cancer is one of the most prevalent cancers in the world, but the research on its prevention, early diagnosis and treatment is still a major challenge in clinical oncology. Thus, there is a pressing requirement to find effective strategies to improve the survival of colon cancer patients.

METHODS

Celecoxib has been accounted to be an effective antitumor drug, but may exhibit significant side effects. In recent studies, 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione (ADT-OH), one of the most commonly used reagents for the synthesis of sustained-release H2 S donors, has also been reported to inhibit cancer progression by affecting processes such as cell cycle, angiogenesis, and apoptosis. Therefore, we evaluated the therapeutic effect of the combination of ADT-OH and celecoxib on colorectal cancer through in vitro and in vivo, hoping to achieve better therapeutic effect and reduce the effect of celecoxib on gastric injury through exogenous administration of H2 S.

RESULTS

Our results demonstrated that ADT-OH combined with celecoxib synergistically inhibited the proliferation and migration ability of human colorectal cancer HCT116 cells, altered cell cycle and cytoskeleton, increased intracellular reactive oxygen species (ROS), and promoted cell apoptosis. Noteworthy, in vivo studies also indicated the excellent antitumor therapeutic effect of the combination therapy without apparent toxicity.

CONCLUSIONS

In general, our results provide a reasonable combination strategy of low-dose ADT-OH and celecoxib in the preclinical application of colorectal cancer.

Total Neoadjuvant Treatment for Locally Advanced Rectal Cancer Patients: Where Do We Stand?

The therapeutic landscape in locally advanced rectal cancer (LARC) has undergone a significant paradigm shift in recent years with the rising adoption of total neoadjuvant treatment (TNT). This comprehensive approach entails administering chemotherapy and radiation therapy before surgery, followed by optional adjuvant chemotherapy. To establish and deliver the optimal tailored treatment regimen to the patient, it is crucial to foster collaboration among a multidisciplinary team comprising healthcare professionals from various specialties, including medical oncology, radiation oncology, surgical oncology, radiology, and pathology. This review aims to provide insights into the current state of TNT for LARC and new emerging strategies to identify potential directions for future research and clinical practice, such as circulating tumor-DNA, immunotherapy in mismatch-repair-deficient tumors, and nonoperative management.

Long-term effect of neoadjuvant radiotherapy in patients with locally advanced rectal mucinous adenocarcinoma: a population-based study of 1514 patients

Rectal mucinous adenocarcinoma (RMAC) is a rare and aggressive form of rectal cancer. The effectiveness of neoadjuvant radiotherapy (NRT) for RMAC has not been well studied, and the survival benefit remains controversial. The purpose of this work was to determine the prognostic role of NRT in patients with RMAC by propensity-score matching (PSM). A retrospective cohort study using the Surveillance, Epidemiology, and End Results from 2004 to 2015 was performed. In the multivariate analysis before PSM, NRT provided better OS (HR 0.61, 95% CI 0.52-0.71, p < 0.001) and CSS (HR 0.68, 95% CI 0.56-0.82, p < 0.001). Multivariate analysis after PSM (n = 844) confirmed that patients receiving NRT survived longer than those without NRT (OS: HR 0.60, 95% CI 0.50-0.78, p < 0.001 and CSS: HR 0.68, 95% CI 0.54-0.84, p < 0.001). Subgroup analysis indicated that NRT had significantly improved OS and CSS in stage II RMAC and OS in stage III RMAC after adjusting for various confounding factors.

Impact of Total Neoadjuvant Therapy on Postoperative Outcomes After Proctectomy for Rectal Cancer

BACKGROUND

Total neoadjuvant therapy is an alternative to neoadjuvant chemoradiation alone for rectal cancer and has the benefits of more completion of planned therapy, increased downstaging, earlier treatment of micrometastases, and assessment of chemosensitivity; however, it may increase surgical complications, especially with increased radiation-to-surgery interval.

OBJECTIVE

The study aimed to determine the impact of total neoadjuvant therapy on postoperative complications compared with neoadjuvant chemoradiation alone.

DESIGN

Retrospective cohort study.

SETTINGS

Single tertiary referral center.

PATIENTS

The patient included was a stage II/III rectal cancer patient who underwent total neoadjuvant therapy or long-course neoadjuvant chemoradiation followed by surgical resection from 2018-2020.

MAIN OUTCOME MEASURES

The main outcome measures included severe postoperative complications (Clavien-Dindo grade ≥3).

RESULTS

Of 181 patients, 86 (47.5%) underwent total neoadjuvant therapy and 95 (52.5%) underwent neoadjuvant chemoradiation. There was no difference in severe postoperative complications or any complications. There was also no difference in the rate of complete total mesorectal excision or negative circumferential margin. Total neoadjuvant therapy had a mean operative time of 355.5 minutes and estimated blood loss of 263.6 mL compared with 326.7 minutes and 297.5 mL in the neoadjuvant chemoradiation group. Total neoadjuvant therapy patients had a lower mean lymph node yield than neoadjuvant chemoradiation patients. On multivariable analysis, total neoadjuvant therapy was associated with increased operative time (OR, 1.19; p < 0.001) and estimated blood loss (OR, 1.22; p < 0.001) and decreased lymph node yield (OR, 0.67; p < 0.001). There was no difference in severe complications or any complications.

LIMITATIONS

Selection bias uncontrolled by modeling.

CONCLUSIONS

We found no difference in risk of postoperative complications between patients who received total neoadjuvant therapy vs neoadjuvant chemoradiation. Total neoadjuvant therapy patients had longer operations and greater estimated blood loss. This may be a reflection of increased operative difficulty because of increased radiation-to-surgery interval and/or the effects of chemotherapy; however, the absolute differences were small and, therefore, should be interpreted cautiously. See Video Abstract at http://links.lww.com/DCR/C44 .

IMPACTO DE LA TERAPIA NEOADYUVANTE TOTAL EN LOS RESULTADOS POSOPERATORIOS DESPUS DE UNA PROCTECTOMA POR CNCER DE RECTO

ANTECEDENTES:La terapia neoadyuvante total es una alternativa a la quimiorradiación neoadyuvante sola para el cáncer de recto y tiene los beneficios de una mayor finalización de la terapia planificada, mayor reducción del estadiage, tratamiento más temprano de las micrometástasis y evaluación de la quimiosensibilidad; sin embargo, puede aumentar las complicaciones quirúrgicas, especialmente con un mayor intervalo entre la radiación y la cirugía.OBJETIVO:Determinar el impacto de la terapia neoadyuvante total sobre las complicaciones posoperatorias en comparación con la quimiorradiación neoadyuvante sola.DISEÑO:Estudio de cohorte retrospectivo.ENTORNO CLINICO:Centro único de referencia terciario.PACIENTES:Paciente con cáncer de recto en estadio II/III que se sometieron a terapia neoadyuvante total o quimiorradiación neoadyuvante de larga duración seguida de resección quirúrgica entre 2018 y 2020.PRINCIPALES MEDIDAS DE RESULTADO:Complicaciones postoperatorias graves (grado de Clavien-Dindo ≥3).RESULTADOS:De 181 pacientes, 86 (47,5%) se sometieron a terapia neoadyuvante total y 95 (52,5%) se sometieron a quimiorradioterapia neoadyuvante. No hubo diferencia en las complicaciones postoperatorias graves o cualquier otra complicación. Tampoco hubo diferencia en la tasa de escisión mesorrectal total completa o margen circunferencial negativo. La terapia neoadyuvante total tuvo un tiempo operatorio promedio de 355,5 minutos y una pérdida de sangre estimada de 263,6 ml en comparación con 326,7 minutos y 297,5 ml en el grupo de quimiorradiación neoadyuvante. Los pacientes con terapia neoadyuvante total tuvieron una media de ganglios linfáticos más bajo en comparación con los pacientes con quimiorradioterapia neoadyuvante. En el análisis multivariable, la terapia neoadyuvante total se asoció con un mayor tiempo operatorio (OR = 1,19, p < 0,001) y pérdida de sangre estimada (OR = 1,22, p < 0,001) y menor cantidad los ganglios linfáticos (OR = 0,67, p < 0,001). No hubo diferencia en las complicaciones graves o cualquier complicación.LIMITACIONES:Sesgo de selección no controlado por modelado.CONCLUSIONES:No encontramos diferencias en el riesgo de complicaciones postoperatorias entre los pacientes que recibieron terapia neoadyuvante total versus quimiorradiación neoadyuvante. Los pacientes con terapia neoadyuvante total tuvieron operaciones más prolongadas y una mayor pérdida de sangre estimada. Esto puede ser un reflejo de una mayor dificultad quirúrgica como resultado de un mayor intervalo entre la radiación y la cirugía y/o los efectos de la quimioterapia; sin embargo, las diferencias absolutas fueron pequeñas y, por lo tanto, deben interpretarse con cautela. Consulte Video Resumen en http://links.lww.com/DCR/C44 . (Traducción- Dr. Francisco M. Abarca-Rendon ).

A refined prediction of early recurrence combining tumor deposits in patients with resected rectal mucinous adenocarcinoma

PURPOSE

Early recurrence (ER) of rectal mucinous adenocarcinoma (MAC) has yet to be defined. We therefore explored risk factors for ER and constructed a predictive nomogram.

METHOD

A total of 145 rectal MAC patients undergoing radical surgery were included. The minimum P value method was used to determine the optimal cut-off point to discriminate between ER and late recurrence (LR). Risk factors for ER were determined by a logistic regression analysis, and a predictive nomogram was constructed.

RESULTS

A total of 62 (42.8%) patients developed tumor recurrence. The optimal time to define ER was 12 months. A pre-treatment tumor distance from the anal verge ≤ 7 cm, pathological N stage, lymphovascular invasion, tumor deposits, and time to recurrence ≤ 12 months were significantly associated with a poor post-recurrence survival in patients with recurrence. A pre-treatment serum carcinoembryonic antigen (CEA) level > 10 ng/ml, pre-treatment tumor distance from the anal verge ≤ 7 cm, pathological N + stage, perineural invasion, and tumor deposits were identified as independent risk factors associated with ER. A nomogram predicting ER was constructed (C-index 0.870).

CONCLUSION

The pre-treatment serum CEA level, pre-treatment tumor distance from the anal verge, pathological N + stage, perineural invasion, and tumor deposits were significantly predictive of ER for rectal MAC patients.

Does Completeness of the Mesorectal Excision Still Correlate With Local Recurrence?

BACKGROUND

Total mesorectal excision is the standard surgical procedure for rectal cancer treatment. Several studies have shown a close correlation between the prognosis of patients with rectal cancer and the completeness of the mesorectal specimen.

OBJECTIVE

To assess the correlation between macroscopic assessment of mesorectal excision and long-term oncological outcomes.

DESIGN

Retrospective analysis of an Institutional Review Board-approved database.

SETTINGS

Tertiary referral center.

PATIENTS

Patients with rectal cancer who were operated on between March 2016 and October 2019 were classified into 3 groups based on the mesorectal specimen quality: complete, near complete, and incomplete. Only patients with a follow-up of ≥2 years and without signs of preoperative distant disease were included.

MAIN OUTCOME MEASURES

Relationship between total mesorectal excision and local and distant recurrence rates in patients with rectal cancer.

RESULTS

A total of 124 patients (35.5% females) were included in the analysis, with a mean age of 58.1 (SD 12) years and a mean BMI of 26.4 (SD 4.59) kg/m². Neoadjuvant chemoradiation was administered to 71% of patients, whereas 13.7% received total neoadjuvant therapy. Restorative procedures were performed in 107 patients (86.3%), whereas 17 patients (13.7%) underwent abdominoperineal resection. The majority of mesorectal excision specimens (87.09%) were complete or near complete. Local recurrence rates were 6.3% (1/16) in the incomplete and 7.4% (8/108) in the complete/near complete group ( p = 0.86). Metachronous distant metastases occurred in 6 patients (37.5%) in the incomplete group and in 24 patients (22.2%) in the complete/near complete group (p = 0.18). Thus, specimen quality did not appear to impact disease-free survival.

LIMITATIONS

Retrospective, single-center study with relatively short follow-up.

CONCLUSIONS

In the era of a multidisciplinary approach and extensive use of neoadjuvant therapy, macroscopic completeness of total mesorectal excision may not be as valuable a prognosticator as in the past. Larger studies with longer follow-ups are needed to clarify these preliminary findings. See Video Abstract at http://links.lww.com/DCR/C129.

LA INTEGRIDAD DE LA ESCISIN MESORRECTAL TODAVA SE CORRELACIONA CON LA RECURRENCIA LOCAL

ANTECEDENTES:La escisión total desl mesorrecto es el estándar de oro para el tratamiento del cáncer de recto. Varios estudios han demostrado una estrecha correlación entre el pronóstico de los pacientes con cáncer de recto y la integridad espécimen mesorrectal.OBJETIVO:Evaluar la correlación entre la evaluación macroscópica de la escisión mesorrectal y los resultados oncológicos a largo plazo en pacientes con cáncer de recto.DISEÑO:Análisis retrospectivo de una base de datos aprobada por el IRB.ENTORNO CLINICO:El estudio se realizó en un centro de referencia terciario de una sola institución.PACIENTES:Todos los pacientes con cáncer de recto operados entre 3/2016-10/2019. Los pacientes se clasificaron en 3 grupos, según la calidad del espécimen mesorrectal: completo, casi completo e incompleto. Solo se incluyeron pacientes con seguimiento >2 años y sin signos de enfermedad a distancia preoperatoria.PRINCIPALES MEDIDAS DE RESULTADO:Identificar la relación entre la escisión mesorrectal total y las tasas de recurrencia local y a distancia en pacientes con cáncer de recto.RESULTADOS:Se incluyeron 124 pacientes (35,5% mujeres) con una edad media de 58,1 años (DE 12) y un índice de masa corporal medio de 26,4 (DE 4,59). Se administró quimiorradiación neoadyuvante al 71% de los pacientes, mientras que el 13,7% recibió terapia neoadyuvante total. Se realizaron procedimientos de restauración en 107 pacientes (86,3%), mientras que 17 pacientes (13,7%) se sometieron a resección abdominoperineal. La mayoría (87,09%) de los especímenes de escisión mesorrectal fueron completas o casi completas. Las tasas de recurrencia local fueron 1/16 (6,3%) en el grupo incompleto y 8/108 (7,4%) en el grupo completo/casi completo ( p = 0,86). Se produjeron metástasis a distancia metacrónicas en 6 pacientes (37,5%) en el grupo incompleto y 24 (22,2%) en el grupo completo/casi completo ( p = 0,18). Por lo tanto, la calidad del espécimen no pareció afectar la supervivencia libre de enfermedad.LIMITACIONES:Estudio retrospectivo de un solo centro con pequeño número de casos y seguimiento relativamente corto.CONCLUSIÓN:En la era de un enfoque multidisciplinario y el uso extensivo de la terapia neoadyuvante, la integridad macroscópica de la escisión total del mesorrecto, puede no ser un pronóstico tan valioso como en el pasado. Se necesitan estudios más amplios con períodos de seguimiento más prolongados para aclarar estos hallazgos preliminares. Consulte Video Resumen en http://links.lww.com/DCR/C129 . (Traducción-Dr. Fidel Ruiz Healy ).

Bladder preservation or complete cystectomy during pelvic exenteration of patients with locally advanced or recurrent rectal cancer, what should we do?

INTRODUCTION

In patients with locally advanced (LARC) or locally recurrent (LRRC) rectal cancer and bladder involvement, pelvic exenteration (PE) with partial (PC) or radical (RC) cystectomy can potentially offer a cure. The study aim was to compare PC and RC in PE patients in terms of oncological outcome, post-operative complications and quality-of-life (QoL).

MATERIALS & METHODS

This was a retrospective cohort analysis of a prospectively maintained surgical database. Patients who underwent PE for LARC or LRRC cancer with bladder involvement between 1998 and 2021 were included. Post-operative complications and overall survival were compared between patients with PC and RC.

RESULTS

60 PC patients and 269 RC patients were included. Overall R0 resection was 84.3%. Patients with LRRC and PC had poorest oncological outcome with 69% R0 resection; patients with LARC and PC demonstrated highest R0 rate of 96.3% (P = 0.008). Overall, 1-, 3- and 5-year OS was 90.8%, 68.1% and 58.6% after PC, and 88.7%, 62.2% and 49.5% after RC. Rates of urinary sepsis or urological leaks did not differ between groups, however, RC patients experienced significantly higher rates of perineal wound- and flap-related complications (39.8% vs 25.0%, P = 0.032).

CONCLUSION

PC as part of PE can be performed safely with good oncological outcome in patients with LARC. In patients with LRRC, PC results in poor oncological outcome and a more aggressive surgical approach with RC seems justified. The main benefit of PC is a reduction in wound related complications compared to RC, although more urological re-interventions are observed in this group.

Improved Survival After Adjuvant Therapy in Locally Advanced Rectal Cancer Patients With Pathologic Complete Response

BACKGROUND

The benefit of adjuvant therapy is unclear in patients with rectal cancer achieving a pathologic complete response after neoadjuvant chemoradiotherapy and total mesorectal excision.

OBJECTIVE

This study aimed to assess the benefit of adjuvant chemotherapy on survival among rectal cancer patients with a pathologic complete response after neoadjuvant chemoradiation.

DESIGN

Retrospective cohort study.

SETTING

National Cancer Database (2004-2017).

PATIENTS

Patients with clinical stage 2 or 3 rectal adenocarcinoma who underwent neoadjuvant chemoradiation (50-50.4 Gy in 25-28 fractions) followed by total mesorectal excision with a pathologic complete response were included.

INTERVENTION

Adjuvant chemotherapy.

MAIN OUTCOME MEASURES

Overall survival.

RESULTS

There were 20,518 patients and 2221 (11%) had a pathologic complete response after neoadjuvant chemoradiation. Of 2221 patients, 1441 (65%) did not receive adjuvant therapy and 780 (35%) did. Patients who received adjuvant therapy were more likely to be younger (median 58 vs 62 y), have private insurance (61% vs 49%), and have node-positive disease (57% vs 48%) (all p < 0.05). There were no differences in sex, race, Charlson-Deyo score, clinical T-stage, tumor size and differentiation, adequate lymphadenectomy (12 or more), or sphincter preservation between groups (all p > 0.05). Overall survival at 5, 10, and 14 years was significantly longer in the adjuvant group (93%, 85%, 83%, respectively) compared to patients who did not receive adjuvant therapy (87%, 67%, 51%, respectively) ( p < 0.001). In a subgroup analysis, adjuvant therapy was associated with improved survival in patients with clinical stage 2 and 3 rectal cancer ( p < 0.001). After adjusting for patient and tumor characteristics, omission of adjuvant chemotherapy was associated with significantly worse survival (HR 1.53, 95% 1.08-2.16).

LIMITATIONS

Selection bias, unknown perioperative morbidity, chemotherapy regimen, recurrence status, and other unidentified factors limiting survival analysis.

CONCLUSIONS

In patients with clinical stage 2 or 3 rectal cancer, adjuvant chemotherapy was associated with improved overall survival in patients achieving a pathological complete response after neoadjuvant chemoradiotherapy. See Video Abstract at http://links.lww.com/DCR/C139 .

SOBREVIDA MEJORADA DESPUS DE LA TERAPIA ADYUVANTE EN PACIENTES CON CNCER DE RECTO LOCALMENTE AVANZADO CON RESPUESTA PATOLGICA COMPLETA

ANTECEDENTES:En los pacientes con cáncer de recto que logran una respuesta patológica completa después de la quimiorradioterapia neoadyuvante y la escisión total del mesorrecto, el beneficio de la terapia adyuvante no está claro.OBJETIVO:Evaluar el beneficio de la quimioterapia adyuvante en la sobrevida de los pacientes con cáncer de recto con una respuesta patológica completa después de la quimiorradioterapia neoadyuvante.DISEÑO:Estudio de cohorte retrospectivo.ESCENARIO:Base de Datos Nacional de Cáncer (2004-2017).PACIENTES:Pacientes con adenocarcinoma rectal en estadio clínico 2 ó 3 que se sometieron a quimiorradiación neoadyuvante (50-50,4 Gy en 25-28 fracciones) seguida de escisión mesorrectal total con una respuesta patológica completa.INTERVENCIÓN:Quimioterapia adyuvante.PRINCIPALES MEDIDAS DE RESULTADO:Sobrevida global.RESULTADOS:Hubo 20.518 pacientes y 2.221 (11%) tuvieron una respuesta patológica completa después de la quimiorradiación neoadyuvante. Entre estos 2221 pacientes, 1441 (65%) no recibieron terapia adyuvante y 780 (35%) sí. Los pacientes que recibieron terapia adyuvante tenían más probabilidades de ser más jóvenes (mediana de 58 frente a 62 años), tener un seguro privado (61% frente a 49%) y tener enfermedad con linfonodos positivos (57% frente a 48 %) (todos p < 0,05). No hubo diferencias en género, raza, puntuación de Charlson-Deyo, estadio T clínico, tamaño y diferenciación del tumor, linfadenectomía adecuada (≥12) o preservación del esfínter entre los grupos (todos p > 0,05). La sobrevida general a los 5, 10 y 14 años fue significativamente mayor en el grupo adyuvante (93%, 85%, 83%, respectivamente) en comparación con los pacientes que no recibieron terapia adyuvante (87%, 67%, 51% respectivamente) ( p < 0,001). En un análisis de subgrupos, la terapia adyuvante se asoció con una mejor sobrevida general en pacientes con cáncer de recto en estadio clínico 2 y 3 ( p < 0,001). Después de ajustar por las características del paciente y del tumor, la omisión de la quimioterapia adyuvante se asoció con una sobrevida global significativamente peor (HR 1,53, IC del 95%, 1,08-2,16).LIMITACIONES:Sesgo de selección; morbilidad perioperatoria desconocida, régimen de quimioterapia, estado de recurrencia y otros factores no identificados que limitan el análisis de sobrevida.CONCLUSIONES:En pacientes con cáncer de recto en estadio clínico 2 ó 3, la quimioterapia adyuvante se asoció con una mejor sobrevida general en pacientes que lograron una respuesta patológica completa después de la quimiorradioterapia neoadyuvante. Consulte Video Resumen en http://links.lww.com/DCR/C139 . (Traducción-Dr. Felipe Bellolio ).

Comparison of quality of life, symptom and functional outcomes following surgical treatment for colorectal neoplasia

BACKGROUND

Colorectal surgical procedures can have a significant impact on quality-of-life (QoL), functional and symptom outcomes. This retrospective study conducted in a tertiary care center evaluated the influence of four colorectal surgical procedures on patient-reported outcome measures (PROMs).

METHODS

512 patients undergoing colorectal neoplasia surgery between June 2015 and December 2017 were identified via the Cabrini Monash Colorectal Neoplasia database. Primary outcomes measured were the mean changes in PROMs following surgery utilizing the International Consortium of Health Outcome Measures colorectal cancer (CRC) PROMs.

RESULTS

242 patients from 483 eligible patients responded (50% participation rate). Responders and non-responders were comparable in median age (72 vs. 70 years), gender (48% vs. 52% male), time from surgery (<1 and >1 year), overall stage at diagnosis and type of surgery. Respondents underwent either a right hemicolectomy, ultra-low anterior resection, abdominoperineal resection or a transanal endoscopic microsurgery/transanal minimally invasive surgery. Right hemicolectomy patients reported the best post-operative function and reduced symptoms, significantly better (P < 0.01) than ultra-low anterior resection patients who reported the worst outcomes in multiple areas (body image, embarrassment, flatulence, diarrhoea, stool frequency). Furthermore, patients undergoing an abdominoperineal resection reported the worst scores for body image, urinary frequency, urinary incontinence, buttock pain, faecal incontinence and male impotence.

CONCLUSIONS

The differences in PROMs in CRC surgical procedures is demonstrable. The worst post-operative functional and symptom scores were reported after either an ultra-low anterior resection or an abdominoperineal resection. Implementation of PROMs will identify and aid early patient referral to allied health and support services.

Circumferential Resection Margin as Predictor of Nonclinical Complete Response in Nonoperative Management of Rectal Cancer

BACKGROUND

Short-course radiation therapy and consolidation chemotherapy with nonoperative intent has emerged as a novel treatment paradigm for patients with rectal cancer, but there are no data on the predictors of clinical complete response.

OBJECTIVE

Evaluate the predictors of clinical complete response and survival.

DESIGN

Retrospective cohort.

SETTINGS

National Cancer Institute-designated cancer center.

PATIENTS

Patients with stage I to III rectal adenocarcinoma treated between January 2018 and May 2019 (n = 86).

INTERVENTIONS

Short-course radiation therapy followed by consolidation chemotherapy.

MAIN OUTCOME MEASURES

Logistic regression was performed to assess for predictors of clinical complete response. The end points included local regrowth-free survival, regional control, distant metastasis-free survival, and overall survival.

RESULTS

A positive (+) circumferential resection margin by MRI at diagnosis was a significant predictor of nonclinical complete response (OR: 4.1, p = 0.009) when adjusting for CEA level and primary tumor size. Compared to patients with a negative (-) pathologic circumferential resection margin, patients with a positive (+) pathologic circumferential resection margin had inferior local regrowth-free survival (29% vs 87%, p < 0.001), regional control (57% vs 94%, p < 0.001), distant metastasis-free survival (43% vs 95%, p < 0.001), and overall survival (86% vs 95%, p < 0.001) at 2 years. However, the (+) and (-) circumferential resection margin by MRI subgroups in patients who had a clinical complete response both had similar regional control, distant metastasis-free survival, and overall survival of more than 90% at 2 years.

LIMITATIONS

Retrospective design, modest sample size, short follow-up, and the heterogeneity of treatments.

CONCLUSIONS

Circumferential resection margin involvement by MRI at diagnosis is a strong predictor of nonclinical complete response. However, patients who achieve a clinical complete response after short-course radiation therapy and consolidation chemotherapy with nonoperative intent have excellent clinical outcomes regardless of the initial circumferential resection margin status. See Video Abstract at http://links.lww.com/DCR/C190 .

EL MARGEN DE RESECCIN CIRCUNFERENCIAL COMO PREDICTOR NO CLNICO DE RESPUESTA COMPLETA EN EL MANEJO CONSERVADOR DEL CNCER DE RECTO

ANTECEDENTES:La radioterapia de corta duración y la quimioterapia de consolidación en el manejo conservador, han surgido como un nuevo paradigma de tratamiento, para los pacientes con cáncer de recto, lastimosamente no hay datos definitivos sobre los predictores de una respuesta clínica completa.OBJETIVO:Evaluar los predictores de respuesta clínica completa y de la sobrevida.DISEÑO:Estudio retrospectivo de cohortes.AJUSTES:Centro oncológico designado por el NCI.PACIENTES:Adenocarcinomas de recto estadio I-III tratados entre 01/2018 y 05/2019 (n = 86).INTERVENCIONES:Radioterapia de corta duración seguida de quimioterapia de consolidación.PRINCIPALES MEDIDAS DE RESULTADO:Se realizó una regresión logística para evaluar los predictores de respuesta clínica completa. Los criterios de valoración incluyeron la sobrevida libre de recidiva local, el control regional, la sobrevida libre de metástasis a distancia y la sobrevida general.RESULTADOS:Un margen de resección circunferencial positivo (+) evaluado por imagenes de resonancia magnética nuclear en el momento del diagnóstico fue un predictor no clínico muy significativo de respuesta completa (razón de probabilidades/ OR: 4,1, p = 0,009) al ajustar el nivel de antígeno carcinoembrionario y el tamaño del tumor primario. Comparando con los pacientes que presetaban un margen de resección circunferencial patológico negativo (-), los pacientes con un margen de resección circunferencial patológico positivo (+) tuvieron una sobrevida libre de recidiva local (29% frente a 87%, p < 0,001), un control regional (57% frente a 94%, p < 0,001), una sobrevida libre de metástasis a distancia (43% frente a 95%, p < 0,001) y una sobrevida global (86% frente a 95%, p < 0,001) inferior en 2 años de seguimiento. Sin embargo, los subgrupos de margen de resección circunferencial (+) y (-) evaluados por imágenes de resonancia magnética nuclear en pacientes que tuvieron una respuesta clínica completa tuvieron un control regional similar, una sobrevida libre de metástasis a distancia y una sobrevida general >90% en 2 años de seguimiento.LIMITACIONES:Diseño retrospectivo, tamaño modesto de la muestra, seguimiento corto y heterogeneidad de tratamientos.CONCLUSIONES:La afectación del margen de resección circunferencial evaluado por resonancia magnética nuclear al momento del diagnóstico es un fuerte factor predictivo no clínico de respuesta completa. Sin embargo, los pacientes que logran una respuesta clínica completa después de un curso corto de radioterapia y quimioterapia de consolidación como manejo conservador tienen excelentes resultados clínicos independientemente del estado del margen de resección circunferencial inicial. Consulte Video Resumen en http://links.lww.com/DCR/C190 . (Traducción-Dr. Xavier Delgadillo ).

Laparoscopic surgery for rectal cancer, specimen extraction: transanal or transabdominal?

BACKGROUND

Comparison of natural orifice specimen extraction (NOSE) and transabdominal specimen extraction (TASE) in colorectal surgery remains controversial. Herein, we aimed to perform a retrospective analysis on surgical outcomes of NOSE and TASE at three hospitals in east of Iran.

METHOD

Consecutive locally advanced rectal adenocarcinoma patients who underwent laparoscopic surgery using either NOSE or TASE from 2011 to 2017 were recruited. These patients were followed-up till 2020. Data, including postoperative complications, long-term overall and recurrence-free survival were analyzed retrospectively.

RESULTS

239 eligible patients were included in this study. 169 (70.71%) patients underwent NOSE, and 70 (29.29%) patients underwent TASE. Although this study has achieved similar outcomes in terms of overall and recurrence-free survival, metastasis, circumferential margin involvement as well as complications of intra-operative bleeding, obstruction, anastomosis-fail, rectovaginal-fistula in women and pelvic collection/abscess in both groups, we observed higher rates of locoregional recurrence, incontinency, stenosis and the close distal margins involvement in NOSE group and also obstructed defecation syndrome in TASE cases.

CONCLUSION

According to our findings, NOSE laparoscopic surgery showed significantly higher incontinency, impotency, stenosis and involvement of the close distal margins rates. Nevertheless, considering the similarity of long-term overall and recurrence-free survival, metastasis, circumferential margin involvement, NOSE procedure is still could be considered as a second choice for lower rectal adenocarcinoma patients.

Comparison of the pathological response to 2 or 4 cycles of neoadjuvant CAPOX in II/III rectal cancer patients with low/intermediate risks: study protocol for a prospective, non-inferior, randomized control trial (COPEC trial)

BACKGROUND

For patients with low- and intermediate-risk stage II/III rectal cancer, current studies have reached a consensus that preoperative radiotherapy may be dispensed with, and neoadjuvant chemotherapy (NCT) alone might achieve an accepted local control. Our previous phase II study has evidenced that the morphological response of NCT could be better judged at a relatively early stage. Low- and intermediate-risk stage II/III rectal cancer patients could achieve a high rate of tumor shrinkage and downgrade after only 4 cycles of NCT and obvious tumor morphological changes could be observed after 2 cycles of NCT. However, there is still a lack of more detailed stratification and evidence for pathological criteria. The aim of the present study (comparison of the pathological response to 2 or 4 cycles of neoadjuvant CAPOX in II/III rectal cancer patients with low/intermediate risks, COPEC trial) is to determine the pathological tumor regression grade (pTRG) rate of 2 or 4 cycles of NCT in low- and intermediate-risk stage II/III rectal cancer and verify the feasibility of early identification of chemotherapy-insensitive population.

METHODS/DESIGN

This is a multicenter, prospective, non-inferior, randomized controlled trial (RCT) initiated by West China Hospital of Sichuan University and designed to be conducted in fourteen hospitals around China. Eligible patients will be centrally randomized into 2 or 4 cycles of CAPOX in a 1:1 ratio using the central automated randomization system offered by the O-trial online system ( https://plus.o-trial.com/ ) and accept total mesorectal excision after 2 or 4 cycles of CAPOX (oxaliplatin 130 mg/m², once daily on day 1, every 21 days and capecitabine 1000 mg/m², twice daily on days 1 to 14, every 21 days). The primary endpoint is the proportion of patients with pathological no-tumor regression (pTRG 3), which is determined postoperatively by each sub-center and verified by the primary center.

DISCUSSION

COPEC trial is designed to verify that the preoperative CAPOX chemotherapy for low- and intermediate-risk stage II/III rectal cancer could achieve a good response judgment after 2 cycles and obtain the tumor pathological response rate after 2 cycles of CAPOX. We hope the COPEC trial could help in establishing a consensus standard of low- and intermediate-risk rectal cancer and the early identification of stage II/III rectal patients with low- and intermediate-risk who are poorly responding to NCT.

TRIAL REGISTRATION

Clinicaltrial.gov NCT04922853. Registered on June 4, 2021.

Delta Radiomic Analysis of Mesorectum to Predict Treatment Response and Prognosis in Locally Advanced Rectal Cancer

BACKGROUND

The aim of this study is to evaluate the delta radiomics approach based on mesorectal radiomic features to develop a model for predicting pathological complete response (pCR) and 2-year disease-free survival (2yDFS) in locally advanced rectal cancer (LARC) patients undergoing neoadjuvant chemoradiotherapy (nCRT).

METHODS

Pre- and post-nCRT MRIs of LARC patients treated at a single institution from May 2008 to November 2016 were retrospectively collected. Radiomic features were extracted from the GTV and mesorectum. The Wilcoxon-Mann-Whitney test and area under the receiver operating characteristic curve (AUC) were used to evaluate the performance of the features in predicting pCR and 2yDFS.

RESULTS

Out of 203 LARC patients, a total of 565 variables were evaluated. The best performing pCR prediction model was based on two GTV features with an AUC of 0.80 in the training set and 0.69 in the validation set. The best performing 2yDFS prediction model was based on one GTV and two mesorectal features with an AUC of 0.79 in the training set and 0.70 in the validation set.

CONCLUSIONS

The results of this study suggest a possible role for delta radiomics based on mesorectal features in the prediction of 2yDFS in patients with LARC.

Local Excision Versus Total Mesorectal Excision After Favourable Response to Neoadjuvant Therapy in Low Rectal Cancer: a Multi-centre Experience

The gold standard surgical management of curable rectal cancer is proctectomy with total mesorectal excision. Adding preoperative radiotherapy improved local control. The promising results of neoadjuvant chemoradiotherapy raised the hopes for conservative, yet oncologically safe management, probably using local excision technique. This study is a prospective comparative phase III study, where 46 rectal cancer patients were recruited from patients attending Oncology Centre of Mansoura University and Queen Alexandra Hospital Portsmouth University Hospital NHS with a median follow-up 36 months. The two recruited groups were as follows: group (A), 18 patients who underwent conventional radical surgery by TME; and group (B), 28 patients who underwent trans-anal endoscopic local excision. Patients of resectable low rectal cancer (below 10 cms from anal verge) with sphincter saving procedures were included: cT1-T3N0. The median operative time for LE was 120 min versus 300 in TME (p < 0.001), and median blood loss was 20 ml versus 100 ml in LE and TME, respectively (p < 0.001). Median hospital stay was 3.5 days versus 6.5 days (p = 0.009). No statistically significant difference in median DFS (64.2 months for LE versus 63.2 months for TME, p = 0.85) and median OS (72.9 months for LE versus 76.3 months for TME, p = 0.43). No statistically significant difference in LARS scores and QoL was observed between LE and TME (p = 0.798, p = 0.799). LE seems a good alternative to radical rectal resection in carefully selected responders to neoadjuvant therapy after thorough pre-operative evaluation, planning and patient counselling.

Evaluation of Predictive and Prognostic Importance of Lung Immune Prognostic Index in Locally Advanced Rectal Cancer Patients Treated With Neoadjuvant Chemoradiotherapy

OBJECTIVE

The systemic inflammatory response (SIR) is known as an important factor associated with tumorigenesis and tumor progression, and can be reflected by inflammatory markers. One of the markers that reflect this is the lung immune prognostic index (LIPI). It is based on a derived neutrophil-to-lymphocyte ratio (dNLR) and lactate dehydrogenase (LDH) level. We aimed to investigate the significance of LIPI in locally advanced rectal cancer (LARC) patients treated with neoadjuvant chemoradiotherapy (NACRT).

METHODS

In this retrospective study, we stratified the patients according to LIPI score as good LIPI and intermediate (int)/poor LIPI. According to pathological response to NACRT, we divided the patients into two groups as those with complete response (CR) or near-CR, and those with partial response (PR) or poor/no response. We classified CR and near-CR as good response. We evaluated the predictive and prognostic significance of LIPI for NACRT response, disease-free survival (DFS), and overall survival (OS) by univariate and multivariate analyses.

RESULTS

We included 137 patients in the results, with 72 (52.6%) having good LIPI and 65 (47.4%) having int/poor LIPI. The median follow-up period was 44.7 months (range: 10-105 months). Thirteen patients (18.0%) in the good LIPI group and 22 patients (34.0%) in the int/poor LIPI group achieved good response. In multivariate analysis, we found only the LIPI score as an independent risk factor (hazard ratio (HR): 2.4, p = 0.04) for NACRT response. Median DFS was 89.2 months (95% CI: 11.4-167.0) in the int/poor LIPI group; however, the DFS of all study populations and patients in the good LIPI group did not reach the median value. In multivariate analysis for DFS, we identified abdominoperineal resection (APR) (HR: 2.21, p = 0.02), presence of tumor deposit (HR: 2.96, p = 0.003), and int/poor LIPI score (HR: 2.07, p = 0.02) as separate risk variables. OS of all study populations and the patients in the LIPI groups did not reach the median value. In multivariate analysis for OS, we identified APR (HR: 2.74, p = 0.02), surgical margin positivity (HR: 12.94, p < 0.001), and adjuvant CT (HR: 0.20, p = 0.002) as separate risk variables for OS.

CONCLUSION

This is the first study investigating the predictive and prognostic significance of LIPI in LARC patients treated with NACRT. The results revealed that int/poor LIPI was associated with a higher rate of good response but shorter DFS compared to good LIPI. The baseline LIPI score serves as an easily accessible and useful prognostic index, and it has significant potential for making appropriate treatment decisions in LARC.

Efficacy of hypofractionated preoperative chemoradiotherapy in rectal cancer

The efficacy and toxicity of hypofractionated preoperative chemoradiotherapy (HPCRT) combined with oral capecitabine was evaluated in patients with rectal cancer. HPCRT was delivered by intensity-modulated radiotherapy of either 33 Gy to the whole pelvis or 35 Gy in 10 fractions to the primary tumor and 33 Gy to the surrounding pelvis. Surgery was performed 4-8 weeks after HPCRT completion. Oral capecitabine was administered concurrently. A total of 76 patients were eligible for this study, and patient numbers in clinical stages I, II, III and IVA were 5, 29, 36 and 6, respectively. Tumor response, toxicity and survival were analyzed. A total of 9/76 patients (11.8%) achieved a pathological complete response. Sphincter preservation was achieved in 23/32 (71.9%) and 44/44 (100%) of patients with a distal extent from the anal verge of ≤5 and >5 cm, respectively. A total of 28/76 patients (36.8%) achieved tumor-downstaging and 25/76 (32.9%) achieved nodal (N)-downstaging. The 5-year disease-free survival (DFS) and overall survival rates were 76.5% and 90.6%, respectively. In the multivariate analysis for DFS, pathological N stage and lymphovascular space invasion were notable prognostic factors. A total of 6 patients in stage IVA underwent salvage treatments for lung or liver metastasis after HPCRT completion, and all 6 were alive at the last follow-up. Only 4 patients experienced grade 3 postoperative complications. No grade 4 toxicities were observed. HPCRT of 33 or 35 Gy in 10 fractions showed similar results to those of long-course fractionation. This fractionation scheme could be beneficial for patients with early stage disease, locally advanced rectal cancer, simultaneous distant metastasis requiring early intervention or for patients who wish to avoid multiple hospital visits.