Rectal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

Combined tumor-associated microbiome and immune gene expression profiling predict response to neoadjuvant chemo-radiotherapy in locally advanced rectal cancer

Locally advanced rectal cancer (LARC) is treated with neoadjuvant chemo-radiotherapy (nCRT) followed by surgery. A minority of patients show complete response (CR) to nCRT and may avoid surgery and its functional consequences. Instead, most patients show non-complete response (non-CR) and may benefit from additional treatments to increase CR rates. Reliable predictive markers are lacking. Aim of this study was to identify novel signatures predicting nCRT responsiveness. We performed a combined analysis of tumor-associated microbiome and immune gene expression profiling of diagnostic biopsies from 70 patients undergoing nCRT followed by rectal resection, including 16 with CR and 54 with non-CR. Findings were validated by an independent cohort of 49 patients, including 7 with CR and 42 with non-CR. Intratumoral microbiota significantly differed between CR and non-CR groups at genus and species level. Colonization by bacterial species of Ruminococcus genera was consistently associated with CR, whereas abundance of Fusobacterium, Porhpyromonas, and Oscillibacter species predicted non-CR. Immune gene profiling revealed a panel of 59 differentially expressed genes and significant upregulation of IFN-gamma and -alpha response in patients with CR. Integrated microbiome and immune gene profiling analysis unraveled clustering of microbial taxa with each other and with immune cell-related genes and allowed the identification of a combined signature correctly identifying non-CRS in both cohorts. Thus, combined intratumoral microbiome-immune profiling improves the prediction of response to nCRT. Correct identification of unresponsive patients and of bacteria promoting responsiveness might lead to innovative therapeutic approaches based on gut microbiota pre-conditioning to increase nCRT effectiveness in LARC.

Recurrence risk following rectal cancer surgery: a survival analysis of key predictors

BACKGROUND

Identifying predictors of postsurgical recurrence in patients with rectal cancer is critical for optimizing postoperative management and improving patient outcomes. We aimed to assess the effects of demographic, clinical, and pathological factors on recurrence risk after rectal cancer surgery.

METHODS

We conducted a secondary analysis of data from patients who underwent curative rectal cancer surgery between 2004 and 2018. A Cox proportional hazards regression model was applied to examine the influence of variables on recurrence risk. Kaplan-Meier curves were used to visualize cumulative hazards.

RESULTS

Among 961 patients (62.7% male, mean age 63.1 years), 127 (13.2%) experienced recurrence over a median follow-up of 60 months. Based on the Cox model (C-index = 0.770, likelihood ratio test χ2(19) = 127.5, P < 0.001), significant predictors of increased recurrence risk included pathologic node stage N1 (hazard ratio 2.92, 95% CI: 1.84-4.63, P < 0.001) and N2 (4.05, 2.36-6.94, P < 0.001), as well as fewer than 12 harvested lymph nodes (1.95, 1.31-2.90, P = 0.001). Moderately differentiated histology reduced recurrence risk (0.49, 0.27-0.89, P = 0.018), and age (0.98, 0.96-0.99, P = 0.004) was inversely correlated with recurrence risk. Sex, chemotherapy, pathologic tumor stage, and lymphovascular invasion were not significant predictors of recurrence.

CONCLUSION

This study identified key factors associated with recurrence risk after rectal cancer surgery, highlighting the importance of pathologic node stage, lymph node metrics, and histological differentiation. These findings provide a foundation for personalized postoperative management strategies and improving long-term outcomes in rectal cancer patients.

Total neoadjuvant therapy for locally advanced rectal cancer

OBJECTIVES

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To assess the effectiveness and safety of total neoadjuvant therapy versus standard therapy in individuals with locally advanced rectal cancer.

Personalized surveillance in colorectal cancer: Integrating circulating tumor DNA and artificial intelligence into post-treatment follow-up

Given the growing burden of colorectal cancer (CRC) as a global health challenge, it becomes imperative to focus on strategies that can mitigate its impact. Post-treatment surveillance has emerged as essential for early detection of recurrence, significantly improving patient outcomes. However, intensive surveillance strategies have shown mixed results compared to less intensive methods, emphasizing the necessity for personalized, risk-adapted approaches. The observed suboptimal adherence to existing surveillance protocols underscores the urgent need for more tailored and efficient strategies. In this context, circulating tumor DNA (ctDNA) emerges as a promising biomarker with significant potential to revolutionize post-treatment surveillance, demonstrating high specificity [0.95, 95% confidence interval (CI): 0.91-0.97] and robust diagnostic odds (37.6, 95%CI: 20.8-68.0) for recurrence detection. Furthermore, artificial intelligence and machine learning models integrating patient-specific and tumor features can enhance risk stratification and optimize surveillance strategies. The reported area under the receiver operating characteristic curve, measuring artificial intelligence model performance in predicting CRC recurrence, ranged from 0.581 and 0.593 at the lowest to 0.979 and 0.978 at the highest in training and validation cohorts, respectively. Despite this promise, addressing cost, accessibility, and extensive validation remains crucial for equitable integration into clinical practice.

Peritoneal reflection involvement as a prognostic factor in rectal cancer. Long-term oncological outcomes from a prospective study

PURPOSE

To assess the relevance of peritoneal reflection involvement in long-term oncological outcomes in patients with rectal cancer.

METHODS

Prospective observational study from a specialized colorectal unit that included a consecutive series of patients undergoing mesorectal excision for rectal cancer. Peritoneal reflection (PR) involvement was evaluated on pathological examination using Shepherd's classification. Overall survival (OS), disease-free survival (DFS), and local recurrence (LR) were assessed.

RESULTS

One hundred sixty patients were included in the present analysis. Peritoneal involvement was present in 28.2% of the 85 tumors above or at the level of PR. There were no differences in OS, DFS, or LR according to tumor's height location. The 5-year OS, DFS, and LR for tumors involving PR were 58.3%, 61.7%, and 30.3%, respectively. Patients with peritoneal involvement had a higher LR rate (p = 0.02) and shorter OS (p = 0.04). Shepherd's grade 4 peritoneal involvement was an independent risk factor for OS (HR 2.9; 95% CI 1.1-9.5, p = 0.04) and LR (HR 4.2; 95% CI 1.2-16.9, p = 0.04).

CONCLUSION

After rectal cancer resection, peritoneal involvement is an independent risk factor for local recurrence and poor survival.

Evaluation of Short-Term Postoperative Outcomes of Lateral Lymph Node Dissection After Neoadjuvant Radiotherapy for Rectal Cancer Patients: The Early Learning Phase After Surgical Training in the Netherlands

BACKGROUND

Distal, locally advanced rectal cancer might spread to lateral lymph nodes (LLNs), posing a risk of lateral local recurrence (LLR). This study evaluated quality-controlled implementation of lateral lymph node dissection (LLND) in the Netherlands.

METHODS

This retrospective multicenter cohort study included consecutively treated rectal cancer patients who underwent neoadjuvant therapy, total mesorectal excision (TME) surgery, and nerve-sparing minimally invasive LLND by trained surgeons across 10 Dutch hospitals. Training involved cadaver sessions, monthly video meetings, and proctoring. Outcome measures included intra- and postoperative complications, urogenital dysfunction and 18-month LLR, local recurrence (LR), and disease-free survival (DFS).

RESULTS

The study comprised 41 patients (median follow-up period, 16 months; interquartile range, IQR, 8-21 months) with advanced tumors (27% cT4, 49% cN2, 7% cM1), and a mean LLN size of 11 mm on primary-staging MRI. Abdominoperineal resection was performed for 29 patients (70%). A beyond TME procedure was performed for 11 patients (28%). The median blood-loss was 250 ml (IQR, 100-400 ml), with obturator nerve injury reported in one patient. Malignant LLNs were found in 41% of the LLND specimens. Complications occurred for 22 patients (54%), 21% (9/41) of which were grade 3 or higher. Nine patients (22%, four of whom underwent beyond TME surgery) had a Foley or intermittent urinary catheter at the end of the follow-up period. Sexual dysfunction of three patients was reported. No ipsilateral LLRs occurred. The 18-month LR rate was 14%, and the DFS was 55%.

CONCLUSION

Minimally invasive nerve-sparing LLND by trained Dutch surgeons showed acceptable complication rates and good oncologic control of the lateral compartment to date.

Metabolomic analysis reveals key changes in amino acid metabolism in colorectal cancer patients

The number of colorectal cancer (CRC) patients is steadily growing worldwide, particularly in developing nations. Nonetheless, recent advances in early detection studies and therapy alternatives have reduced CRC mortality in affluent countries, despite rising incidence. Gut microbiota and their metabolites may contribute to tumor growth and reduced therapeutic efficacy. This preliminary study sought to uncover metabolic fingerprints in colorectal cancer patients. It also emphasizes the correlation between the gut microbiome, microbial metabolism, and altered metabolites in CRC. In this study, stool samples from 20 CRC patients and matched healthy controls were enrolled. Untargeted metabolomics approach based on an ultra-high-performance liquid chromatography high-resolution mass spectrometry (UHPLC-MS/MS) were applied. Statistical approaches, pathway enrichment analysis, and network analysis were employed to unleash CRC perturbed metabolic pathways and putative biomarkers. The study identified a distinct manually curated metabolite profile that is substantially linked to CRC. The steroidogenesis, aspartate, tryptophan (Trp), and urea cycle were the most significant pathways that concurrently contributed to CRC.Prominently, among other pathways, Trp metabolism was identified as a critical pathway, indicating a possible connection between the development of CRC and gut microbiota. In a nutshell the notable resulted metabolites reveal auspicious biomarkers for the initial diagnosis as well as surveilling of CRC progression. This preliminary study highlights the potential involvement that gut bacteria may contribute in CRC patients. Further investigation into the composition of the gut microbiome associated with this metabolic profile may lead to the identification of novel biomarkers for early detection and possible targets for treatment.

Approvers, Disapprovers, and Strugglers: a Q-methodology study of rectal cancer MRI proforma use

OBJECTIVES

Rectal cancer MRI (rcMRI) allows accurate staging and informs treatment decisions in rectal cancer. There is variability in reporting completeness; however, template proforma reports can significantly increase the inclusion of key tumour descriptors. We aimed to identify socially shared viewpoints of radiologists relating to barriers to implementing proforma reporting. Measuring the subjectivity of opinions relative to other radiologists will allow identification of common patterns preventing implementation.

METHODS

Specialist gastrointestinal radiologists from 16 hospital trusts were invited to a Q-methodology study. Participants ranked 56 statements on barriers to using proforma reports (the Q-set) in a normal distribution (Q-grid). Factor analyses were undertaken to identify independent accounts, and additional survey data were used to support interpretation.

RESULTS

Twenty-seven radiologists participated; 11 (41%) had more than 10 years reporting rcMRIs. Three distinct accounts of radiologist attitudes to proforma-use were identified: Approvers, Disapprovers, and Struggling champions. The highest ranked barriers related to proforma format, individual radiologists' preferences and beliefs about efficacy and factors relating to wider multidisciplinary teams and health system-level implementation.

CONCLUSIONS

Radiologists that disapprove of proformas are unlikely to use them unless external influences are applied, such as a requirement by treating clinicians. Increased internal and organizational support would also increase use. Targeted implementation strategies focusing on these barriers has the potential to increase uptake of similar interventions.

ADVANCES IN KNOWLEDGE

Specialist radiologists require a multi-level adaptive implementation strategy, tailored to proforma characteristics as well as individual and organizational barriers to increase proforma reporting for rcMRI to support accurate treatment decision making.

Prospective radiotherapy quality Assurance leads to delineation guideline refinements for recurrent rectal cancer: Experience from the PelvEx II study

Introduction

Target volume delineation in locally recurrent rectal cancer (LRRC) is clinically challenging. To ensure the quality of chemoradiotherapy (CRT) within the PelvEx II trial, a delineation guideline was developed and prospective quality assurance (QA) was instated for all patients. Guideline adherence, the impact of QA on target volumes, and subsequent guideline refinements are described in this paper.

Methods and materials

All PelvEx II patients, either RT naive patients (50-50.4 Gy) or reirradiation (30 Gy) patients, were eligible for QA prior to CRT. An online meeting with the treating physician and the QA team was planned for each patient prior to treatment, to peer review delineations. Adherence to each of the 7 (reirradiation) or 8 (RT naive) guideline recommendations was scored. Suggested target volume adjustments and any reasons to deviate from protocol were noted. When applicable, target volumes before and after QA were compared. Possible protocol refinements were discussed amongst the trial QA team.

Results

Prospective review of 113 cases of LRRC was performed, resulting in a high QA compliance rate of 90 %. All guideline recommendations were followed in 53 % of cases. Changes to the GTV and CTV were advised in 21 and 39 cases respectively. A median increase of GTV (+29 % (p < 0.001)) and CTV (+15 % (p < 0.001)) was seen in reirradiation patients, versus a median CTV increase of + 6 % (p = 0.002) in RT naive patients following QA. Deviations from protocol were accepted in 30 cases (27 %). Thirteen protocol refinements were agreed upon.

Conclusion

Peer-review of LRRC target volumes leads to altered target volumes in up to 48% of cases, resulting in an updated delineation guideline.

Neoadjuvant chemotherapy and chemoradiotherapy versus chemoradiotherapy alone in high-risk locally advanced rectal cancer: A retrospective comparison of two Dutch tertiary referral centres

INTRODUCTION

The effect of neoadjuvant chemotherapy and chemoradiotherapy in patients with locally advanced rectal cancer, at increased risk of failing current treatment regimens, is unknown. This study compared the complete response rate and long-term survival of these patients treated with or without neoadjuvant chemotherapy prior to chemoradiotherapy.

MATERIALS AND METHODS

Patients with high-risk locally advanced rectal cancer, who were surgically treated or entered a watch and wait approach after neoadjuvant chemoradiotherapy with or without neoadjuvant chemotherapy in Erasmus Medical Centre or Catharina Hospital between 2016 and 2020, were retrospectively identified. High-risk was defined as the presence of tumour invasion into the mesorectal fascia, grade 4 extramural venous invasion, enlarged lateral lymph nodes, or tumour deposits. The primary endpoint was complete response rate, which was defined as a histopathological complete response or a sustained (during 12 months) clinical complete response. Long-term oncological outcomes were evaluated based on Kaplan-Meier and Cox regression survival analyses.

RESULTS

The neoadjuvant chemotherapy group consisted of 64 patients, of whom 61 (95.3 %) were treated with chemotherapy prior to chemoradiotherapy, the chemoradiotherapy group of 194 patients. The complete response rates were 25.0 % and 9.8 %, respectively (P = 0.002). The estimated 3-year overall survival was 92.2 % in the neoadjuvant chemotherapy group versus 66.9 % in the chemoradiotherapy group.

CONCLUSION

Excellent oncological outcomes were observed in patients with high-risk locally advanced rectal cancer selected during a multidisciplinary team (MDT) meeting for neoadjuvant chemotherapy and chemoradiotherapy. The actual difference with patients treated with chemoradiotherapy alone should be investigated in prospective trials. Pretreatment referral to expert MDTs is encouraged.

Quality of Life and Functional Outcomes in Patients With Locally Advanced Rectal Cancer Receiving Total Neoadjuvant Therapy Versus Concurrent Chemoradiation Therapy: An Analysis of the STELLAR Trial

PURPOSE

To explore differences in the effects of total neoadjuvant therapy (TNT) and preoperative concurrent chemoradiation therapy (CRT) on quality of life and functional outcomes in patients with locally advanced rectal cancer.

METHODS AND MATERIALS

In the study, 591 patients with distal or middle-third, clinical primary tumor stage cT3 to 4 and/or regional lymph node-positive rectal cancer were randomly assigned (1:1) to receive short-term radiation therapy (25 Gy in 5 fractions) followed by 4 cycles of CAPOX (TNT group, n = 297) or standard CRT (50 Gy in 25 fractions concurrently with oral capecitabine) (CRT group, n = 294) before surgery. After a 6-year follow-up, the surviving patients were sent surveys, including the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ)-C30, EORTC QLQ-CR29, and Wexner incontinence score questionnaires. Differences between the 2 groups were compared, and baseline data from the general population who completed the EORTC QLQ-C30 were also compared.

RESULTS

The median follow-up was 77.38 (59.07-103.20) months, with 196 out of 414 surviving patients (47.3%) completing the questionnaire. Patients in the TNT group had better emotional function (94.16 ± 10.19 vs 90.17 ± 14.63, P = .031) but more severe diarrhea (12.46 ± 21.73 vs 6.74 ± 16.03, P = .036) than did those in the CRT group. However, the mean differences between the 2 groups were <5 points, which is not clinically significant, and there were no significant differences in other quality of life items. The Wexner incontinence scores were 5 (0-6) and 3 (0-6) for the TNT and CRT groups, respectively, with no significant difference between the groups (P = .357). Compared to the general population data from the completed EORTC QLQ-C30 assessment, the patients did not exhibit differences >5 points in terms of worse function or more severe symptoms.

CONCLUSIONS

There were no significant differences in quality of life or anal function between patients receiving TNT and those receiving CRT. After 6 years, patients were able to maintain stability.

Laparoscopic approach for rectal cancer surgery: triumph of reason or necessity of evolution?

The role of laparoscopy in rectal cancer surgery has evolved considerably since the early 2000s. Initial randomized trials, such as COLOR II and COREAN, indicated that laparoscopic approaches offered similar pathological outcomes with better postoperative recovery than open surgery. In contrast, trials like ACOSOG Z6051 and ALaCaRT suggested noninferiority could not be established. Variability in trial outcomes, focusing on either disease-free survival or pathological measures, initially hindered consensus. Long-term analyses have shown no significant difference in disease-free survival between laparoscopic and open approaches. Meta-analyses have reinforced the benefits of laparoscopic surgery, with reduced mortality and similar oncologic effectiveness to open surgery. However, new techniques like transanal TME (TaTME) and robotic approaches have introduced alternatives, though each presents unique challenges, from recurrence rates in TaTME to costs in robotics. While laparoscopy remains the preferred method due to accessibility and outcomes, robotic surgery is expected to gain traction in high-volume centers.

The Degree of Extramural Spread of T3 Colon Cancer as a Prognostic Factor: Another Appeal to the American Joint Committee on Cancer

BACKGROUND

The pT3 category of colon cancer staging is heterogeneous and has significant prognostic value. However, this is not reflected in the current TNM staging system. The objective of this work is to determine whether the extent of infiltration beyond the muscularis propria of pT3 colon carcinoma is an independent risk factor for worse oncologic outcomes after curative surgery.

METHODS

Retrospective analysis of 536 patients from a tertiary University Hospital with pT3M0 colon cancer (1995-2015) was collected and re-evaluated to assess tumor infiltration extent beyond the muscularis propria layer. The main outcome measures studied were local recurrence, systemic recurrence, disease-free survival, and cancer-specific survival.

RESULTS

An infiltration extent of 5 mm was the best cutoff for predicting oncological results in this group of patients. Multivariable analysis showed that tumor infiltration depth into the pericolic fat was an independent risk factor for a higher local recurrence rate (p = 0.02, HR 1.11 per mm, 95% CI 1.04-1.23), a higher risk of systemic recurrence (p = 0.02, HR 1.08 per mm, 95% CI 1.01-1.16), worse disease-free survival (p = 0.008, HR 1.08 per mm, 95% CI 1.02-1.14), and cancer-specific survival (p = 0.009, HR 1.09 per mm, 95% CI 1.02-1.16). In a sub-analysis, these results were confirmed in patients with positive lymph nodes but not in the group of patients with negative lymph nodes.

CONCLUSIONS

The extramural spread of pT3 colon cancer is a significant prognostic factor for worse oncological outcomes after curative surgery. Therefore, this parameter should be considered in selecting adjuvant therapy and possibly included in the TNM staging system.

Risk score model for predicting local control and survival in patients with rectal cancer treated with neoadjuvant chemoradiotherapy

The present study aimed to investigate clinicopathological factors affecting local recurrence and survival in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT) and to create a risk-scoring model predicting local control (LC) and survival. The clinical and pathological data of 115 patients who received nCRT for LARC between February 2010 and December 2020 were reviewed retrospectively. A risk-scoring model was developed to predict LC and survival using statistically significant prognostic factors in univariate and multivariate analyses. In the multivariate analysis, the LC rate was improved in patients with a good pathological response to nCRT. By contrast, the disease-free survival (DFS) rate was significantly worse in patients with perineural invasion (PNI). The overall survival (OS) rate was significantly worse in patients who were >60 years of age, who had tumors ≥5 cm, who were PNI-positive and who had pathological N2 stage disease. Patients were grouped to analyze the ability of the scoring system to predict LC and survival. The total score was derived by assigning points to the prognostic factors in univariate and multivariate analyses and was subsequently divided into three groups according to tertile. The median LC times in groups 1-3 were significantly different at 143.6, 97.2 and 93.6 months, respectively. The median DFS times in groups 1-3 were significantly different at 136.1, 108.5 and 67.2 months, respectively, while the median OS times in groups 1-3 were significantly different at 138.3, 87.2 and 64.6 months, respectively. In conclusion, risk score modeling with prognostic factors effectively determined the difference in LC and survival between the groups. Adding effective systemic therapy to nCRT may improve results, especially in patients with multiple poor prognostic factors, including larger tumors, PNI and multiple nodal involvement.

Prediction of metachronous liver metastasis in mid-low rectal cancer using quantitative perirectal fat content from high-resolution MRI

PURPOSE

To investigate the relationship between perirectal fat content and metachronous liver metastasis (MLM) in patients with Mid-low rectal cancer (MLRC).

MATERIALS AND METHODS

A retrospective analysis was conducted on 254 patients who underwent curative surgery for MLRC between December 2016 and December 2021. Preoperative MRI measurements of the rectal mesenteric fat area (MFA), rectal posterior mesorectal thickness (PMT), and rectal mesenteric fascia envelopment volume (MFEV) were performed, along with collection of relevant clinical, pathological, and imaging data. Patients were categorized into the MLM group (Group A), other recurrence or metastasis group (Group B), and no recurrence and metastasis group (Group C). Analyze the differences between Group A and the other groups, and independent risk factors for MLM were explored. Kaplan-Meier analysis and log-rank test were used to validate independent predictive biomarkers for MLM.

RESULTS

Patients with MLM from MLRC had later pathological and imaging T stages and lower perirectal fat content (all P < 0.05). Compared to patients with other types of recurrent metastasis, male gender, poorly differentiated tumors, and advanced tumor N stage were more likely to develop MLM (all P < 0.05). In Cox univariate and multivariate regression analysis, smaller rectal PMT (hazard ratio (HR) 0.361 [0.154-0.846], P = 0.019) and MFEV (HR 0.983 [0.968-0.998], P = 0.022) were independently associated with MLM in MLRC (HR 0.361;0.983). Kaplan-Meier analysis showed that patients with rectal PMT <1.43 cm and rectal MFEV <137.46 cm3 had a significantly higher risk of MLM compared to patients with rectal PMT ≥1.43 cm and rectal MFEV ≥137.46 cm3 (all P < 0.05).

CONCLUSION

Rectal PMT and rectal MFEV can serve as novel parameters for predicting MLM in patients with MLRC.

Neoadjuvant Radiotherapy vs Up-Front Surgery for Resectable Locally Advanced Rectal Cancer

Importance

Guidelines for resectable locally advanced rectal cancer (LARC) advocate for neoadjuvant radiotherapy (NRT) followed by surgery as the standard approach. However, recent trials have reported no oncological benefits of NRT-based therapy for middle or lower rectal cancer, raising the question of whether NRT followed by surgery remains the optimal treatment approach for resectable LARC overall.

Objective

To compare the outcomes of NRT followed by surgery vs up-front surgery for resectable LARC.

Design, Setting, and Participants

This cohort study, using a target trial emulation framework with nationwide registries in Taiwan, included patients undergoing curative resection for resectable LARC (cT1-2N1-2, cT3Nany) between January 1, 2014, and December 31, 2017, with follow-up until December 31, 2020. Data were analyzed from January 1, 2024, to February 15, 2025.

Exposure

NRT.

Main Outcomes and Measures

The primary outcomes were overall survival (OS) and local recurrence (LR). The secondary outcome was intraoperative diverting stoma outcomes.

Results

A total of 4099 patients were analyzed, including 1436 patients undergoing NRT followed by surgery (median [IQR] age, 62.0 [53.0-71.0] years; 1036 [72.1%] male) and 2663 patients undergoing up-front surgery (median [IQR] age, 65.0 [56.0-74.0] years; 1626 [61.1%] male). NRT followed by surgery, compared with up-front surgery, was associated with higher 3-year OS rates (88.5% vs 85.2%; hazard ratio [HR], 0.74; 95% CI, 0.59-0.92) but higher permanent diverting stoma rates (20.6% vs 11.1%; relative risk [RR], 1.91; 95% CI, 1.62-2.25); LR rates were not significantly different (5.7% vs 6.6%; HR, 0.78; 95% CI, 0.55-1.11). Subgroup analysis revealed that compared with up-front surgery, NRT followed by surgery was associated with improved outcomes in middle or lower rectal cancer but not upper rectal cancer (OS: HR, 1.54; 95% CI, 0.82-2.90; LR: HR, 1.08; 95% CI, 0.23-5.00). NRT followed by surgery was associated with significantly increased risks of permanent diverting stomas across different tumor heights, particularly in upper rectal cancer (RR, 3.54; 95% CI, 1.44-8.69).

Conclusions and Relevance

In this cohort study of nationwide registries in Taiwan, NRT followed by surgery was associated with improved oncological outcomes for overall resectable LARC, with excessive diverting stoma nonreversal as the trade-off. However, the benefits of NRT were not observed for upper rectal cancer. These findings raise concerns about potential harm from NRT and advise caution when performing NRT for upper rectal cancer.

Computer-aided diagnosis tool utilizing a deep learning model for preoperative T-staging of rectal cancer based on three-dimensional endorectal ultrasound

BACKGROUND

The prognosis and treatment outcomes for patients with rectal cancer are critically dependent on an accurate and comprehensive preoperative evaluation.Three-dimensional endorectal ultrasound (3D-ERUS) has demonstrated high accuracy in the T staging of rectal cancer. Thus, we aimed to develop a computer-aided diagnosis (CAD) tool using a deep learning model for the preoperative T-staging of rectal cancer with 3D-ERUS.

METHODS

We retrospectively analyzed the data of 216 rectal cancer patients who underwent 3D-ERUS. The patients were randomly assigned to a training cohort (n = 156) or a testing cohort (n = 60). Radiologists interpreted the 3D-ERUS images of the testing cohort with and without the CAD tool. The diagnostic performance of the CAD tool and its impact on the radiologists' interpretations were evaluated.

RESULTS

The CAD tool demonstrated high diagnostic efficacy for rectal cancer tumors of all T stages, with the best diagnostic performance achieved for T1-stage tumors (AUC, 0.85; 95% CI, 0.73-0.93). With assistance from the CAD tool, the AUC for T1 tumors improved from 0.76 (95% CI, 0.63-0.86) to 0.80 (95% CI, 0.68-0.94) (P = 0.020) for junior radiologist 2. For junior radiologist 1, the AUC improved from 0.61 (95% CI, 0.48-0.73) to 0.79 (95% CI, 0.66-0.88) (P = 0.013) for T2 tumors and from 0.73 (95% CI, 0.60-0.84) to 0.84 (95% CI, 0.72-0.92) (P = 0.038) for T3 tumors. The diagnostic consistency (κ value) also improved from 0.31 to 0.64 (P = 0.005) for the junior radiologists and from 0.52 to 0.66 (P = 0.005) for the senior radiologists.

CONCLUSION

A CAD tool utilizing a deep learning model based on 3D-ERUS images showed strong performance in T staging rectal cancer. This tool could improve the performance of and consistency between radiologists in preoperatively assessing rectal cancer patients.

Unusual skull metastasis in colorectal adenocarcinoma

Colorectal cancer ranks as the third most commonly diagnosed cancer globally. Research suggests that colon cancer and rectal cancer differ in terms of aetiology and risk factors. Follow-up is essential due to the detrimental impact of metastasis on patient survival (5-year survival rate of less than 20%). Routine use of positron emission tomography (PET-CT) is not recommended. This case report describes an elderly woman diagnosed who had previously been treated for rectal cancer. CT scans of the abdomen and chest showed no evidence of metastatic disease. During the second year of follow-up, a PET-CT was performed and a new active osseous lesion in the skull was identified. Current follow-up guidelines for colorectal carcinoma may not encompass all potential metastatic sites. Incorporating full body PET-CT scans into the follow-up protocol could be beneficial for detecting additional metastatic sites.

Comparative efficacy and safety of endoscopic submucosal dissection versus transanal endoscopic microsurgery for the treatment of rectal polyps: a systematic review and meta-analysis

Rectal cancer represents approximately 35% of colorectal cancer cases in the European Union. Early-stage tumors may be treated with less invasive techniques, such as endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM). This systematic review and meta-analysis evaluates the comparative efficacy and safety of ESD versus TEM for early-stage rectal cancer. A literature search was conducted in PubMed, Scopus, Embase, and Cochrane databases up to October 2024. Studies comparing ESD and TEM outcomes in adult patients with rectal tumors were included. Outcomes assessed included the rates of en-bloc resection, recurrence, overall complications, R0 resection rates, postoperative bleeding, reoperation rates, perforation rates, operative time, and length of hospital stay. Statistical analyses were performed using both fixed and random effects models. Seven retrospective studies involving 671 patients were included. Pooled analyses showed that ESD achieved higher en-bloc resection rates [odds ratio (OR) = 0.29, 95% confidence interval (CI): 0.10-0.83, P = 0.02), lower tumor recurrence rates (OR = 0.29, 95% CI: 0.12-0.70, P = 0.006) and lower overall complication rate (OR = 0.50, 95% CI: 0.31-0.81, P = 0.005). No significant differences were observed in terms of R0 resection rates, operative time, postoperative bleeding, and reoperation rates. ESD achieves favorable outcomes over TEM for early-stage rectal cancer by achieving higher en-bloc resection rates, lower rates of recurrence, and complications. Despite ESD's technical complexity, its superior precision and lower complication profile make it a promising option for early-stage rectal cancer, though clinician expertise and available resources should guide treatment selection.

MRI radiomics prediction modelling for pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer: a systematic review and meta-analysis

PURPOSE

Predicting response to neoadjuvant therapy in locally advanced rectal cancer (LARC) is challenging. Organ preservation strategies can be offered to patients with complete clinical response. We aim to evaluate MRI-derived radiomics models in predicting complete pathological response (pCR).

METHODS

Search included MEDLINE, Embase and Cochrane Central Register of Controlled Trials (CENTRAL) and Cochrane Database of Systematic Reviews (CDSR) for studies published before 1st February 2024. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) and Radiomics Quality Score (RQS) tools were used to assess quality of included study. The research protocol was registered in PROSPERO (CRD42024512865). We calculated pooled area under the receiver operating characteristic curve (AUC) using a random-effects model. To compare AUC between subgroups the Hanley & McNeil test was performed.

RESULTS

Forty-four eligible studies (12,714 patients) were identified for inclusion in the systematic review. We selected thirty-five studies including 10,543 patients for meta-analysis. The pooled AUC for MRI radiomics predicted pCR in LARC was 0.87 (95% CI 0.84-0.89). In the subgroup analysis 3 T MRI field intensity had higher pooled AUC 0.9 (95% CI 0.87-0.94) than 1.5 T pooled AUC 0.82 (95% CI 0.80-0.83) p < 0.001. Asian ethnicity had higher pooled AUC 0.9 (95% CI 0.87-0.93) than non-Asian pooled AUC 0.8 (95% CI 0.75-0.84) p < 0.001.

CONCLUSION

We have demonstrated that 3 T MRI field intensity provides a superior predictive performance. The role of ethnicity on radiomics features needs to be explored in future studies. Further research in the field of MRI radiomics is important as accurate prediction for pCR can lead to organ preservation strategy in LARC.

Prediction of the Therapeutic Response to Neoadjuvant Chemotherapy for Rectal Cancer Using a Deep Learning Model

Objectives

Predicting the response to chemotherapy can lead to the optimization of neoadjuvant chemotherapy (NAC). The present study aimed to develop a non-invasive prediction model of therapeutic response to NAC for rectal cancer (RC).

Methods

A dataset of the prechemotherapy computed tomography (CT) images of 57 patients from multiple institutions who underwent rectal surgery after three courses of S-1 and oxaliplatin (SOX) NAC for RC was collected. The therapeutic response to NAC was pathologically confirmed. It was then predicted whether they were pathologic responders or non-responders. Cases were divided into training, validation and test datasets. A CT patch-based predictive model was developed using a residual convolutional neural network and the predictive performance was evaluated. Binary logistic regression analysis of prechemotherapy clinical factors showed that none of the independent variables were significantly associated with the non-responders.

Results

Among the 49 patients in the training and validation datasets, there were 21 (42.9%) and 28 (57.1%) responders and non-responders, respectively. A total of 3,857 patches were extracted from the 49 patients. In the validation dataset, the average sensitivity, specificity and accuracy was 97.3, 95.7 and 96.8%, respectively. Furthermore, the area under the receiver operating characteristic curve (AUC) was 0.994 (95% CI, 0.991-0.997; P<0.001). In the test dataset, which included 750 patches from 8 patients, the predictive model demonstrated high specificity (89.9%) and the AUC was 0.846 (95% CI, 0.817-0.875; P<0.001).

Conclusions

The non-invasive deep learning model using prechemotherapy CT images exhibited high predictive performance in predicting the pathological therapeutic response to SOX NAC.

Evaluating primary tumor position variation for rectal cancer patients treated with long course radiotherapy

Objective.To quantify interfraction shape and positional variations of primary tumor volumes for rectal cancer patients receiving long course radiotherapy by comparing two quantification strategies: a center-of-mass (COM) method and a surface-based metric that captures local deformations.Approach.This study utilized repeat MRI scans before and during radiotherapy (RT) for rectal cancer to investigate the positional variation of the primary gross tumor volume (GTVp). Sixteen patients underwent six MRI exams, with the initial three before the RT course and the subsequent three at one, two, and four weeks into the RT course. GTVp's were delineated on 3D T2-weighted MRIs, and positional variation analyzed using both COM and point-based surface displacements against the initial scan. Surface displacements were quantified using a bidirectional local distance measure, analyzing 3D displacement vectors. Additionally, the study examined local right-left (RL) and anterior-posterior (AP) surface variations relative to tumor height in the rectum by mapping baseline GTVp volumes onto a reference rectum structure.Main results.Systematic error for COM measurements were 1.7, 1.3 and 2.0 mm for AP, RL, and cranial-caudal (CC) direction, respectively. Random errors were 2.1, 1.2 and 2.2 mm, while the GM errors were -0.3, 0.5 and -0.3 mm for AP, RL, and CC directions, respectively. An increase in systematic and random errors were observed when comparing 95th percentile surface displacements to the COM measurements, indicating local displacements which the COM did not detect. Additionally, a general tendency for higher-located tumors to experience larger left-right and AP surface variations were seen when evaluating the 95th percentile.Significance.COM-based analysis might underestimate local deformations. Consequently, surface-based methods might provide more robust estimations of systematic, random and group mean errors for planning target volume-margin calculation. The surface variations tend to increase for tumors located in the upper part of the rectum.

The Landmark Series: Neoadjuvant Therapy for Locally Advanced Rectal Cancer

The management of locally advanced rectal cancer (LARC) has seen much development over recent decades. Neoadjuvant radiotherapy combined with high-quality total mesorectal excision saw improvements in locoregional control. With the advent of several key trials, neoadjuvant therapy for LARC has seen a shift toward total neoadjuvant therapy, with corresponding improvements in tumor response and survival outcomes. The collective pool of evidence has allowed for increasingly personalized treatment of LARC, with organ-preservation now an option for many. The aims of the review are to summarize the evolution of neoadjuvant therapy for LARC, highlight key studies informing contemporary best practices, navigate the complexity of options available, and present areas of ongoing development.

The Potential Health Economic Value of Adding Magnetomotive Ultrasound to Current Diagnostic Methods for Detecting Lymph Node Metastases in Rectal Cancer

BACKGROUND

Local resection of early rectal cancer (RC) is a desirable treatment option compared with surgery, offering reduced morbidity, mortality, health care costs and avoidance of stoma. However, local resection is restricted to cases without suspicion of lymph node metastases (LNM). Current methods to diagnose LNM and risk estimations based on histopathology cannot reliably identify patients eligible for local resection. The NanoEcho diagnostic system is based on a novel method for lymph node staging in RC. The aim of this study was to perform a health economic analysis at an early stage of clinical development to estimate the potential value of adding NanoEcho diagnostics to current diagnostic methods in RC.

METHODS

A Markov model for RC diagnosis was developed where the costs and health outcomes, including quality-adjusted life years (QALYs), for adding the NanoEcho diagnostics to current diagnostic methods were compared with current diagnostic methods alone. The diagnostic performance of the NanoEcho diagnostic system is still unknown and the base-case analysis was performed at an assumed 85% sensitivity and 85% specificity. Two testing strategies corresponding to two alternative ways of implementing the diagnostic test in clinic were evaluated: (1) examine all patients diagnosed with RC and (2) examine only patients diagnosed with clinical stages T1 and T2.

RESULTS

Adding the NanoEcho diagnostic system resulted in a gain of 0.032 life years and 0.124 QALYs per patient in the target population compared with current diagnostic methods alone. At a cost-neutral level, the estimated justifiable price of NanoEcho diagnostics was SEK 6995 in the first testing strategy and SEK 50,658 in the second testing strategy. The justifiable price of the NanoEcho diagnostics at a willingness to pay of 500,000 SEK/QALY was SEK 10,654 in the first testing strategy and SEK 65,132 in the second testing strategy.

CONCLUSION

The results indicate that adding NanoEcho diagnostics to standard of care can potentially reduce healthcare costs and increase quality of life in RC patients, assuming a sensitivity and specificity of 85%.

Differentiating rectal cancer grades using virtual magnetic resonance elastography and fractional order calculus diffusion model

BACKGROUND

To investigate the value of virtual magnetic resonance elastography (vMRE), fractional order calculus (FROC) model, and diffusion-weighted imaging (DWI) in differentiating rectal cancer grades.

METHODS

This prospective study included 74 patients with rectal cancer who underwent a pelvic MRI. The Mann-Whitney U test or independent samples t-test was employed to compare the parameters of vMRE (µMRE), the FROC model (D, β, and µ), and DWI (ADC). Logistic regression analysis and area under the receiver operating characteristic curve (AUC) were utilized separately for multiparameter co-diagnosis and to assess diagnostic performance. Pearson's correlation analysis was conducted to evaluate the relationship of different parameters.

RESULTS

Compared to the low-grade group, the high-grade group had higher µMRE and µ values and lower D, β, and ADC values (all P < 0.05). In terms of the different parameters, the D value demonstrated the highest diagnostic efficacy with an AUC of 0.852(95% CI: 0.750-0.924). In terms of the various methods, the FROC model (D + β + µ) had the highest diagnostic performance with an AUC of 0.943(95% CI: 0.864-0.984), which was significantly higher than those of DWI and vMRE (Z = 3.586, 2.430, and 2.081, all P < 0.05). µMRE showed moderately negative correlations with ADC, D, and β (r = - 0.553, - 0.683, and - 0.530, respectively, all P < 0.05) and a moderately positive correlation with µ (r = 0.443, P < 0.05).

CONCLUSION

FROC, vMRE, and DWI can be utilized for assessing rectal cancer grades, with FROC offering comparatively better diagnostic performance.

A High-resolution T2WI-based Deep Learning Model for Preoperative Discrimination Between T2 and T3 Rectal Cancer: A Multicenter Study

RATIONALE AND OBJECTIVES

To construct a deep learning model (DL) based on high-resolution T2-weighted images for preoperative differentiation between T2 and T3 stage rectal cancer (RC), and to compare its performance with experienced radiologists.

METHODS

This retrospective study included 281 patients with pathologically confirmed RC from four centers (January 2017-December 2022). A DenseNet model was developed using 255 patients from three centers (training:validation ratio=8:2) and externally tested on 26 patients from a fourth center. Two experienced radiologists independently assessed T staging. Diagnostic performance was evaluated using accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC).

RESULTS

The DL model outperformed radiologists in differentiating T2 and T3 stages across all datasets. In the training set, the DL model achieved an AUC of 0.810, compared to 0.578 and 0.625 for radiologists A and B, respectively. In the external test set, the DL model maintained superior diagnostic performance (AUC=0.715) compared to radiologist A (AUC=0.549) and radiologist B (AUC=0.493). The DL model demonstrated higher accuracy for T2 staging (0.625-0.787) and T3 staging (0.611-0.814) compared to radiologists (0.373-0.526 for T2; 0.611-0.783 for T3), who showed a tendency to over-stage T2 tumors. Inter-observer agreement between radiologists was moderate (kappa=0.451).

CONCLUSION

The DenseNet-based DL model demonstrated superior accuracy and diagnostic efficiency than radiologists in preoperative differentiation between T2 and T3 stages RC. This automated approach could potentially improve staging accuracy and support clinical decision-making in RC treatment planning.

Investigation of changes in planning target volume and regression probability of rectal boost using in-silico cone-beam computed tomography-guided online-adaptive radiotherapy

Background and purpose

Radiotherapy boost to the primary tumour may enable organ preservation in locally advanced rectal cancer (LARC). This study evaluated cone-beam computed tomography (CBCT)-guided online-adaptive radiotherapy (ART) to reduce rectal boost planning target volume (PTVBoost) margins and allow dose escalation.

Materials and methods

Eleven LARC patients were included in this in silico study. Population-based PTVBoost margins were computed for non-adaptive and online-ART using van Herk's formalism. Dose/volume results were compared between: non-adaptive RT with a 25 x 2.16 Gy boost (Non-ART54Gy), ART with a 25 x 2.16 Gy boost (ART54Gy), and ART with an escalated boost of 25 x 2.4 Gy (ART60Gy). Tumour regression probability was compared between each plan using a dose-response model.

Results

PTVBoost margins for non-adaptive vs. online-ART were 14.2 vs. 3.3 mm in the antero-posterior, 5.0 vs. 3.2 mm in the left-right, and 12.3 vs. 8.7 mm in the supero-inferior axes. PTVBoost and pelvic lymph node PTV coverage (V95%) were significantly improved with ART54Gy and ART60Gy compared to Non-ART54Gy (p < 0.001). High-priority organ-at-risk constraints (priority 1&2) were violated in 26.8 % of cases for Non-ART54Gy, 21.2 % of cases for ART54Gy, and 20.8 % of cases for ART60Gy. Tumour regression probability was superior for ART60Gy (20.8 %) compared to ART54Gy (17.0 %, p < 0.001) and Non-ART54Gy (16.9 %, p < 0.001).

Conclusions

Online-ART significantly reduce rectal boost PTV margin. It allows better target volume coverage with a similar risk of radiation-induced toxicities, even when escalating the dose. Therefore, online-ART should be considered to perform dose-escalation in LARC patients with the objective of organ preservation.

Is Colonoscopy Alone Adequate for Surveillance in Stage I Colorectal Cancer?

PURPOSE

While colonoscopy is the standard surveillance tool for stage I colorectal cancer according to National Comprehensive Cancer Network guidelines, its effectiveness in detecting recurrence is debated. This study evaluates recurrence risk factors and patterns in stage I colorectal cancer to inform comprehensive surveillance strategies.

MATERIALS AND METHODS

A retrospective analysis of 2,248 stage I colorectal cancer patients who underwent radical surgery at Samsung Medical Center (2007-2018) was conducted. Exclusions were based on familial history, prior recurrences, preoperative treatments, and inadequate data. Surveillance included colonoscopy, laboratory tests, and computed tomography (CT) scans.

RESULTS

Stage I colorectal cancer patients showed favorable 5-year disease-free survival (98.3% colon, 94.6% rectum). Among a total of 1,467 colon cancer patients, 26 (1.76%) experienced recurrence. Of the 781 rectal cancer patients, 47 (6.02%) experienced recurrence. Elevated preoperative carcinoembryonic antigen levels and perineural invasion were significant recurrence risk factors in colon cancer, while tumor budding was significant in rectal cancer. Distant metastasis was the main recurrence pattern in colon cancer (92.3%), while rectal cancer showed predominantly local recurrence (50%). Colonoscopy alone detected recurrences in a small fraction of cases (3.7% in colon, 14.9% in rectum).

CONCLUSION

Although recurrence in stage I colorectal cancer is rare, relying solely on colonoscopy for surveillance may miss distant metastases or locoregional recurrence outside the colorectum. For high-risk patients, we recommend considering regular CT scans alongside colonoscopy. This targeted approach may enable earlier recurrence detection and improve outcomes in this subset while avoiding unnecessary scans for the low-risk majority.

Age Matters: Early-Onset Rectal Cancer Exhibits Higher Rates of Pathological Complete Response: A Retrospective Analysis of the Influence of Young Age on Treatment Success in Stage II-III Rectal Cancer

BACKGROUND

The incidence of rectal cancer has decreased overall, but the incidence of early-onset rectal cancer (eoRC) has increased. Early-onset rectal cancer and late-onset rectal cancer (loRC) differ due to phenotypical, genetic characteristics, and higher stage presentations in eoRC. Thus, eoRC patients undergo more aggressive neoadjuvant treatments. This paper was designed to evaluate the impact of age on the pathological complete response rates in sporadic locally advanced rectal cancer.

METHODS

All patients with stage II-III rectal cancer who underwent neoadjuvant therapy and curative rectal resection between January 2018 and December 2023 were included and allocated to eoRC (<50 years) and loRC (≥50 years) groups based on their age at diagnosis.

RESULTS

A total of 381 patients were included (93 eoRC and 288 loRC). Preoperative radiological imaging revealed higher clinical nodal staging in the eoRC group (p = 0.002). A higher proportion of eoRC resulted in a pathological complete response compared with loRC (29% vs. 18.8%, p = 0.035). The rate of pathological complete response in eoRC and loRC did not differ between patients treated by total neoadjuvant therapy (TNT) and those treated by standard chemoradiotherapy (29.2% vs. 28.6%, p = 0.95 in eoRC and 21.7% vs. 25.9%, p = 0.097 in loRC). Multivariable analysis resulted in young age of onset (odds ratio 2.68; 95% confidence interval 1.11-6.51; p = 0.029) and KRAS wildtype (odds ratio 3.37; 95% confidence interval 1.25-9.07; p = 0.016) as being independent predictors of pathological complete response.

CONCLUSIONS

Sporadic eoRC and KRAS wildtype tumors are predictive factors for pathological complete response in stage II-III rectal cancer.

[Rectal Cancer: Optimal Preoperative Diagnostics]

Preoperative diagnostics for rectal cancer aim to determine the extent of local and systemic spread. Local staging includes rectoscopy with accurate height localisation, histological confirmation, MRI of the pelvis and, particularly in the case of localised tumours, endosonography. In addition to tumour height and possible infiltration of adjacent organs, MRI findings should include minimum tumour distance from the mesorectal fascia and MR morphological criteria for extramural vascular invasion. In the case of lower rectal cancer, the relationship to the various components of the sphincter muscle is important in planning the surgical strategy; in the case of upper rectal cancer, the MRI findings should include possible infiltration of the peritoneal fold. As outlined in the German guidelines, the basic diagnostic tests required to detect or exclude distant metastases are a chest X-ray and an abdominal ultrasound. If unclear findings are observed, these should be supplemented by a chest and abdominal CT. In addition to the carcinoembryonic antigen (CEA) test, which is primarily used for follow-up, a complete colonoscopy should be performed to rule out a second malignancy in the colon. If this is not possible due to an obstructive tumour, the colonoscopy should be performed three months postoperatively. Additionally, a preoperative CT or MR colonoscopy can reliably detect larger polyps and carcinomas.

The prognostic outcome of tumor deposit in colorectal cancer beyond stage N staging

BACKGROUND

Tumor deposits (TD) have been shown to have prognostic implications in patients diagnosed with colorectal cancer (CRC), although their impact appears to be modest compared to regional lymph node metastases.

PATIENTS AND METHODS

A retrospective analysis was conducted involving patients with colorectal cancer in stages I-III who underwent curative resections between January 2015 and December 2019 in the tertiary care center in Thailand. These patients were divided into two cohorts: TD positive and TD negative. Additionally, the patients were subsequently classified into N0, N1, and N2 groups. Disease-free survival and overall survival were compared.

RESULTS

Among the 1015 eligible patients, 176 (17.3 %) had tumor deposits (TD), while 374 patients (36.8 %) had positive lymph nodes (LN). The TD positive group demonstrated a significantly lower 5-year overall survival rate (OS) and 5-year disease-free survival rate (DFS) compared to the TD negative group (73.5 % vs 85.9 %, p < 0.001 and 72.5 % vs 87.9 %, p < 0.001 respectively). Upon stratification by various N stages, the presence of TD was notably associated with DFS in the N1 group (5-year DFS: 84.3 % vs. 89.2 %, p = 0.006). Multivariate logistic analyses shown TD as an independent predictor of disease recurrence [p = 0.02; hazard ratio (HR):1.71 (1.11-2.64)].

CONCLUSION

The presence of TD was significantly correlated with reduced overall survival (OS) and disease-free survival (DFS) in colorectal cancer, especially in patients with nodal metastases.

Relevance of indeterminate pulmonary nodules in predicting distant metastasis in colorectal cancer

BACKGROUND

The detection of indeterminate pulmonary nodules (IPN) at diagnosis of colorectal cancer (CRC) has increased. However, there is limited information on predictive factors for its progression (pPF) to pulmonary metastases (PM). This study aims to identify these pPF to select appropriate management strategies.

METHODS

Single-center observational retrospective study including patients who underwent elective surgery for first non-metastatic CRC episode (January 2016- June 2019) with IPN at diagnosis. Patients were divided into those who developed PM in the same location as previous IPN (LM group) and those who did not (FM group).

RESULTS

One hundred twenty-one patients were included; 4.9% developed PM in the same location as previous IPN. Univariate analysis revealed a significant difference in IPN size between groups with 8 (5, 10) mm in LM versus 3 (1, 5) mm in FM (P=0.006). ROC curve showed a size of ≥5 mm as the best cutoff point to predict IPN progression. Multivariate analysis identified size ≥5mm as the only independent pPF (OR 11.9, 95%CI 1.3-105.8, P=0.026). The median time to diagnose PM in LM group was 13.8(SD 5.2) months.

CONCLUSIONS

We recommend a closer follow-up for patients with CRC and IPN ≥5 mm at diagnosis so they will have a higher risk of developing PM.

Local resection in rectal cancer: When, who and how?

Local resection (LR) in rectal cancer is indicated in stage T1N0M0 without unfavorable pathological factors, achieving oncologically satisfactory outcomes through transanal endoscopic surgery techniques. However, the initial step involves accurate staging and selection of these tumors through specific tests conducted in specialized colorectal units. For T2N0M0 tumors and T1 tumors with poor prognostic factors, the standard treatment is total mesorectal excision (TME), a procedure associated with high postoperative morbidity and mortality, functional impairments, and reduced quality of life. Therefore, new organ-preservation strategies are being explored as alternatives to TME. These include neoadjuvant therapy combined with LR, which has shown promising results, and neoadjuvant therapy followed by a "Watch and Wait" approach -where patients with complete clinical response are selected for strict surveillance- as an ideal future treatment, although there are still current challenges to be addressed.

Early Detection of Local Recurrence After Rectal Cancer Resection in Asymptomatic Patients Is Essential for Survival

BACKGROUND AND OBJECTIVES

Despite advancements in rectal cancer treatment, therapy of local recurrence remains a significant challenge as it has to be individualized to the extent of recurrence and prior treatment. This study aims to analyze outcomes of patients with local recurrence after resection for rectal cancer, focusing on R0-resection rates and overall survival (OS).

METHODS

A retrospective cohort study included 31 patients with local recurrence after initial curative resection for rectal cancer between 2003 and 2021.

RESULTS

Recurrence was diagnosed in 77.4% of cases during scheduled routine follow-up and 58,1% of patients reported of symptoms at the time of diagnosis. Symptomatic patients tended to be treated palliatively (66.7%, 12/18, p = 0.073). A curative treatment approach was intended in 48.4% of all patients, with 80% achieving R0-resection by surgery. The 5-year OS was significantly longer in patients achieving R0-resection (58.3% vs. 5.3%, p = 0.0) and decreased in symptomatic patients (11.1% vs. 46.2%, p = 0.025).

CONCLUSIONS

These findings emphasize the importance of early recurrence detection, optimally in a scheduled cancer follow-up.

Diagnostic yield of follow-up in patients undergoing surgery for non-metastatic colorectal cancer

BACKGROUND

Evidence on adherence, diagnostic performance and impact on survival to intensive follow-up after surgery for colorectal cancer (CRC) is limited.

AIM

To analyze the diagnostic performance of surveillance colonoscopy, computed tomography (CT), and tumor markers (TMs) in detecting CRC recurrence or metastasis during follow-up after CRC resection. Secondary objectives included degree of adherence to clinical practice guidelines surveillance recommendations and factors associated with adherence and all-cause and CRC mortality.

METHODS

The single-center retrospective cohort study including patients undergoing curative resection of stage I-III CRC during 2010-2015. Follow-up was performed using TMs every 6 months, yearly CT for 5 years, and colonoscopy at years 1 and 4. Demographic, primary tumor data, and results at follow-up were collected.

RESULTS

Of 574 included patients included, 153 had recurrences or metastases. Of this group, 136 (88.9%) were diagnosed by CT, 10 (6.5%) by CT and colonoscopy, and 7 (4.6%) by colonoscopy; only 67.8% showed TMs elevation. Adherence to follow-up recommendations was 68.8% for the first colonoscopy, 74% for the first CT scan, and 96.6% for the first blood test; these values declined over time. Younger age at diagnosis [odds ratio (OR) 0.93; 95%CI: 0.91-0.95], CRC stages I-II (OR 0.38; 95%CI: 0.24-0.61), and adherence to follow-up recommendations (OR 0.30; 95%CI: 0.20-0.46) were independently associated with lower risk for all-cause death at 5 years.

CONCLUSION

CT scan had the highest diagnostic yield. Adherence to follow-up recommendations was low and decreased during follow-up. Younger age at diagnosis, stage, and follow-up adherence were associated with lower 5-year mortality.

Results of radical treatment of locally advanced rectal cancer in geriatric and non-geriatric patients

BACKGROUND

It is estimated that 60% of new rectal cancer cases will be diagnosed in patients ≥ 65 years old. The geriatric patient is heterogeneous and underrepresented in clinical trials, and oncologic therapies are often tailored with little evidence. We describe a cohort of patients diagnosed with locally advanced rectal cancer in geriatric and non-geriatric patients.

MATERIALS AND METHODS

Retrospective and descriptive analysis of 137 patients, 44 (32.1%) ≥ 75 years old and 93 (67.9%) ≤ 75 years old, with diagnosis of locally advanced rectal cancer. All patients received neoadjuvant chemoradiotherapy (nCRT), followed by total mesorectal excision (TME) and adjuvant chemotherapy.

RESULTS

Mean age was 79.5 for ≥ 75 years and 62.7 for ≤ 75 years, tumor location was: upper rectum (16.1% and 11.3%), middle rectum (60.2% and 47.7%) and lower rectum (23.7% and 41%), using the Eastern Cooperative Oncology Group (ECOG) 0: 74.1% and 81.8%, ECOG 1: 25.9% and 18.2%. Pathological complete response was 21.5% and 22.7%, partial response, 57% and 59% and no response, 21.5% and 18.3%, respectively. Tumor shrinkage in both groups after neoadjuvant treatment was 34.5% and 35.46%. Local recurrence was 2.2% and 3.2% and distance recurrence, 11.3% and 8.6%, respectively.

CONCLUSION

The study shows similar outcomes in both groups following radical treatment, with similar rates of pathological complete response. However, it has notable limitations, including a small sample size and the absence of a comprehensive geriatric assessment. To enhance these findings, future research should involve larger patient cohorts with comparative analysis and clinical trials specifically focused on the geriatric population.

Extended pelvic lymphadenectomy and rectal cancer: An umbrella review

Extended pelvic lymph node dissection (EPLND) for rectal cancer is common in Asian countries to reduce local recurrence and improve survival. This umbrella review investigates the benefit of adding extended lymphadenectomy to the standard total mesorectal excision (TME) practice. We conducted a comprehensive search of PubMed, Scopus, and Web of Science to identify systematic reviews and meta-analyses examining the role of EPLND in rectal cancer surgery. Primary outcomes were local recurrence and overall survival; secondary outcomes included: operation time, blood loss, urinary dysfunction, and sexual dysfunction. Of the 953 articles screened, 12 met the inclusion criteria. The median follow-up time was 52 months. In terms of overall survival, 10 studies found no statistically significant difference in the EPLND group; only two showed a significant improvement in 5-year survival. Nine studies found no significant benefit of EPLND in preventing local recurrence, while two suggested benefits for patients with locally advanced cancer after neoadjuvant chemoradiotherapy. In most studies, operation time and blood loss were higher in the EPLND group. EPLND was associated with increased odds of urinary and sexual dysfunction, with four out of six studies reporting higher rates for both outcomes. Our analysis concludes that EPLND offers no additional benefit over TME alone in terms of local recurrence, overall survival, or secondary outcomes, including increased risks of urinary and sexual dysfunction, longer operation times, and greater blood loss.

Why did we encounter a pCRM-positive specimen whose preoperative MRI indicates negative mesorectal fascia involvement in middle to low rectal cancer?

BACKGROUND

This study aims to examine why we encounter a pathological circumferential resection margin (pCRM)-positive specimen whose preoperative MRI indicates negative mesorectal fascia involvement in middle to low rectal cancer.

METHODS

Forty-four consecutive patients included in this study had c(yc)T1-3 primary rectal adenocarcinoma without mesorectal fascia involvement and underwent laparoscopic total mesorectal excision (TME) with curative intent in the Department of Gastrointestinal Surgery of Kansai Medical University Hospital from January 2014 to April 2018. We adopted three checkpoints to investigate the misleading point causing positive pCRM (≤ 1 mm). (1) c(yc)CRM diagnosis by two radiologists with more than 20 and 15 years of experience in rectal cancer MRI diagnosis. (2) The specimen was assessed using the TME score presented by Nagtegaal. (3) We compared the standard sectioning according to UK guidelines (group A; n = 26) with the specimen MRI image navigation-based section (group B; n = 18) in terms of estimation of pCRM by c(yc)CRM.

RESULTS

We achieved a "complete" resection specimen in all cases. A simple correlation coefficient in group B revealed a significant correlation between c(yc)CRM and pCRM (r = 0.663, p = 0.00513); this correlation was not significant in group A (r = 0.261, p = 0.19824). However, tests for differences between linear regression coefficients in groups A and B showed no significant differences (p = 0.12596). There were five cases of pCRM ≤ 1 mm: three in group A and two in group B. An anterior lesion caused pCRM ≤ 1 mm in three cases; the tumor deposits or extramural vascular invasion caused the other cases.

CONCLUSION

The cause of misleading pCRM was the inaccurate preoperative MRI diagnosis of c(yc)CRM.

Risk of recurrence following transanal endoscopic microsurgery without neoadjuvant or adjuvant treatment in T2 rectal cancer

BACKGROUND

Transanal endoscopic microsurgery (TEM) is only curative treatment for T1 rectal cancer with low-risk features. In T2 cancer, TEM is not recommended but could be used as a palliative procedure and/or in patients unfit for surgery. Few studies exist investigating recurrence after TEM for T2 rectal cancer.

METHOD

Retrospective, population-based study using the Swedish Colorectal Cancer Registry. Included patients had T2 rectal adenocarcinoma treated with TEM or surgery without neoadjuvant or adjuvant therapy between 2009 and 2021. Patients lost to follow-up, with syn/metachronous tumours or unknown recurrence status were excluded. Patient characteristics, perioperative morbidity, local and distant recurrence were compared.

RESULTS

63 patients treated with TEM and 894 with surgery. Median age was 81 and 70 (p < 0.01). 59 % and 23 % respectively were ASA III-IV (p < 0.01). TEM tumours were more distal, 37 % vs 16 % in the lower third of the rectum (p < 0.01). There were no severe complications after TEM compared to 6 % following surgery (p = 0.04). 5-year local recurrence was 33 % after TEM and 2 % after surgery (HR = 25.58, (p < 0.01). 5-year distant recurrence rate was 9 % after TEM and 7 % after surgery (HR = 0.49, (p = 0.27). Mean time to local recurrence was 16 months after TEM, 34 months after surgery, time to distant recurrence 22 months after both.

CONCLUSION

TEM for T2 rectal cancer has high risk of local recurrence and cannot be recommended when intent is curative. TEM could be an option for patients unfit for surgery.

Total neoadjuvant treatment, non-operative management and radiotherapy-free strategies: New approaches for the management of proficient mismatch repair/microsatellite stable locally advanced rectal cancer. A narrative review and evidence-based algorithm

In recent years, new therapeutic approaches have emerged in addition to classical neoadjuvant (chemo)radiotherapy for the treatment of locally advanced rectal cancer (LARC): total neoadjuvant treatment, non-operative management, and radiotherapy-free strategy. While the introduction of these approaches in a relatively short timeframe has quickly increased our therapeutic armamentarium, on the other hand it has complicated the decision-making process regarding the choice of the most appropriate treatment strategy for each patient with LARC. Therefore, a tool to interpret the evidence from clinical trials and to translate them into daily practice is highly demanded. In the present review, we address how these new developments are changing the multimodal treatment of LARC and offer an algorithm to integrate them into clinical practice.

E_N_T_R_O_P_Y: Monocentric analysis of rectal cancer radio-chemotherapy treatment in patients of young age

Purpose//objectives

A disproportionate incidence's increase of rectal cancer in patients younger than 50 years of age. The ESMO and NCCN recommendations are not age-specific and the literature is poor and conflicting. We decided to examine patients with rectal cancer treated in our centre in the last 15 years with curative neoadjuvant radiochemotherapy comparing outcomes in the two groups under and over 55 years old.

Materials/methods

788 rectal cancer patients were enrolled in this monocentric retrospective observational study (523 =>55 years and 265 < 55). All patients received neoadjuvant chemoradiation treatment. R statistical software v.4.1.3 was used for the entire analysis. The outcomes were death, local recurrence, and new distant metastases. Survival analysis was performed using the Kaplan-Meier method and the Log-rank was used to compare the two groups.

Results

All patients were classified in different risk groups, according to the ESMO 2017 rectal cancer clinical practice guidelines. 88 % of patients under 55 years old at the diagnosis belonged to the bad or advanced risk groups with an equal division. In patients over 55 years old, there was a clear dominance of the advanced risk class (62 % of the total). In multivariate analysis, OS and DFS decrease with increasing age and ESMO risk group. The other variables in multivariate were not significant. For Both OS, DFS and MFS, the curves separated significantly at 55 years of age, with a prevalence of metastasis development in the older group.

Conclusion

Elderly patients have a prevalence of advanced disease. Younger patients seem having a better OS at 3 and 5 years. ESMO risk group and age were the only variables affecting OS and DFS. Young patients have better MFS and DFS at 2 and 5 years than patients older than 55 years. The addition of oxaliplatin to fluoropyrimidine-based neoadjuvant chemotherapy resulted not significant in both groups.

Comparison of the efficacy of neoadjuvant chemotherapy and neoadjuvant chemoradiotherapy in locally advanced rectal cancer patients: meta-analysis of randomized controlled trials

BACKGROUND

Preoperative neoadjuvant chemoradiotherapy (nCRT) is considered to be the standard treatment strategy for locally advanced rectal cancer (LARC); however, the risk of adverse events and postoperative recurrence remains significant. This study aimed to evaluate the non-inferiority of neoadjuvant chemotherapy (nCT) compared with nCRT in patients with LARC and to assess the possibility of eliminating radiotherapy on the basis of guaranteed efficacy.

MATERIALS AND METHODS

We searched the PubMed, Embase, and Cochrane Library databases to identify randomized controlled trials (RCTs) comparing the efficacy of nCRT and nCT for LARC. The study protocol was registered with the Prospective Register of Systematic Reviews (PROSPERO).

RESULTS

A total of 2706 patients from seven studies were included in the meta-analysis. There was no significant difference in overall survival (OS) or disease-free survival (DFS) between the nCT and nCRT groups. This study demonstrated a lower rate of infection (OR = 0.53, 95% CI = 0.34-0.82; P = 0.005), anastomotic leak (OR = 0.55, 95% CI = 0.34-0.87; P = 0.01), tumor regression grade (TRG) 0-1 (OR = 0.50, 95% CI = 0.36-0.69; P < 0.0001), preventive diverting ileostomy (OR = 0.41, 95% CI = 0.17-1.02; P = 0.05), and leukopenia (OR = 0.50, 95% CI = 0.25-1.01; P = 0.05) in the nCT group. However, there was no significant difference in the other toxic events, such as intestinal obstruction, urinary complications, diarrhea, and surgical or pathological outcomes, such as clinical fistula, sphincter preservation, postoperative mortality (≤ 60 d), R0 resection, ypStage 0-I, positive circumferential resection margin (CRM+), or pathological complete response (pCR) between the two groups.

CONCLUSION

This study indicated that OS and DFS were not lower in the nCT group than in the nCRT group. In addition, the nCT group had fewer complications. Preoperative nCT is expected to become a standard treatment option for most patients with stage II-III LARC. It is worth noting that radiotherapy cannot be ignored for some patients who need to ensure the conversion effect of neoadjuvant therapy and strongly request to preserve organ function.

Should endoscopic submucosal dissection be offered to patients with early colorectal cancer?

BACKGROUND

Endoscopic submucosal dissection is increasingly used to treat early-stage colorectal cancer. This study evaluated the feasibility of endoscopic submucosal dissection in this setting and the determinants of lymph node metastasis.

METHODS

We reviewed patients who underwent colorectal endoscopic submucosal dissection for early-stage colorectal cancer at a tertiary center between 2011 and 2023. The primary outcome was the identification of high-risk pathologic features predictive of lymph node metastasis in patients undergoing oncologic colon resection following endoscopic submucosal dissection.

RESULTS

We reviewed 1,398 patients who underwent endoscopic submucosal dissection, and 83 (6%) had colorectal cancer. Twenty-four patients (29%) were closely monitored after endoscopic submucosal dissection, and 59 (71%) underwent oncologic colon resection because of high-risk pathologies of the endoscopic submucosal dissection specimen. In the oncologic colon resection group, the mean age was 62.7 years (±10.2), with 56% male predominance, and 14% showed positive lymph nodes in the final pathology. Analysis comparing patients with and without lymph node metastasis showed significant differences in sex, lesion size, submucosal invasion depth, and budding scores. Multivariate analysis showed that lesions with a submucosal invasion depth ≥2.00 mm of the endoscopic submucosal dissection resection specimen had higher odds of lymph node metastasis (odds ratio 18.7, P = .028), whereas lesions with a diameter >20 mm were associated with a lower likelihood of lymph node metastasis (odds ratio 0.07, P = .036).

CONCLUSION

The study highlights the oncologic safety of early-stage endoscopic submucosal dissection as a viable treatment option for carefully selected patients with colorectal cancer. After tissue resection with endoscopic submucosal dissection, if the lesion size is less than 20 mm, depth of invasion up to 2 mm may be considered safe in the absence of other high-risk pathologic factors.

Radiation-Enhanced AF1q Moves Center Stage as a Key Driver to Favorable Tumor Stage in Rectal Cancer Patients

BACKGROUND

Enhanced protein expression of ALL1-fused gene from chromosome 1q (AF1Q) after (chemo)radiotherapy has been described in vitro, but is largely understudied in gastrointestinal cancer. We aimed to investigate AF1q expression in rectal cancer (RC) patients treated with short-term radiation therapy and a possible correlation with markers crucial for RC prognosis.

METHODS

A cohort of 75 RC patients scheduled for surgery was defined and patients with moderately locally advanced tumors (cT3Nx) received preoperative hyperfractionated short-term radiation therapy (cumulative dose 25 Gy). Immunohistochemical analysis was conducted to assess AF1q, STAT1, IDO1 and other prognostic markers (CD3/CD8-Immunoscore, PD-L1) and marker correlations were evaluated.

RESULTS

Irradiated tumors exhibited significantly higher AF1q expression than treatment-naïve samples (n = 60: AF1q + to AF1q+++ 98.3% (n = 59), AF1q- 1.7% (n = 1) vs. n = 15: AF1q + 78.6% (n = 11), AF1q- 21.4% (n = 4); p < 0.001). Specifically, irradiated tumors showed high STAT1, but low IDO1 expression compared to treatment-naïve samples (p = 0.019 and p = 0.015, respectively). Overall, enhanced tumoral AF1q expression was associated with negative lymph node stage (p = 0.012) as well as with diminished expression of STAT1 (rs = -0.468, p = 0.038) and IDO1 (rs = -0.246, p = 0.020).

CONCLUSION

AF1q is expressed in RC, especially after short-term radiation therapy. Here, AF1q may support tumor suppression, possibly through the involvement of the pro-apoptotic STAT1 axis. Further mechanistic evidence and investigation involving a larger patient cohort are needed to validate a radiation-induced, AF1q-driven tumor-suppressing effect, which may impact RC patient outcomes.

Intensity-modulated radiation therapy can reduce acute toxicities in long-course neoadjuvant radiation therapy combined with S-1 for locally advanced rectal cancer

BACKGROUND

The purpose of this study was to compare outcomes and adverse events between three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) in patients undergoing long-course neoadjuvant radiation therapy (NA-RT) for locally advanced rectal adenocarcinoma (LARC).

METHODS

We retrospectively analyzed a total of 47 consecutive patients who received NA-RT for LARC between January 2011 and September 2022. Seven and 40 patients were diagnosed with clinical stages II and III, respectively. The prescribed dose per fraction was 1.8 Gy for total doses of 45 or 50.4 Gy. Seventeen and 30 patients received 3D-CRT and IMRT, respectively. NA-RT was delivered with concurrent chemotherapy of oral administration of S-1.

RESULTS

Planned NA-RT was completed without any treatment interruption in 43 of the 47 patients. Two patients experienced treatment interruption, and two patients discontinued due to grade ≥ 3 toxicities. No significant differences were observed between patients receiving 3D-CRT and IMRT in local control, progression-free survival, and overall survival (P = 0.488, 0.259, and 0.636, respectively). Patients receiving IMRT showed significantly fewer non-hematological grade ≥ 2 acute toxicities than those receiving 3D-CRT (33.3% vs. 70.6%, P = 0.018). In addition, patients who received IMRT tended to have less intestinal toxicity of grade ≥ 2 than those who received 3D-CRT (P = 0.057).

CONCLUSION

IMRT significantly reduced grade ≥ 2 acute toxicities without compromising oncologic outcomes compared to 3D-CRT. Therefore, IMRT may be considered as a current standard treatment in the total neoadjuvant therapy era.

Impact of belly board immobilization devices and body mass factor on setup displacement using daily cone-beam CT in rectal cancer radiotherapy

OBJECTIVE

The objective of this study is to evaluate the impact of different belly board and daily changes in patient's body-mass factor (BMF) on setup displacement in radiotherapy for rectal cancer.

METHODS

Twenty-five patients were immobilized using the thermoplastic mask with belly board (TM-BB), and 30 used the vacuum bag cushion with belly board (VBC-BB), performing daily cone-beam computed tomography (CBCT) scans 625 times and 750 times, respectively. Daily pretreatment CBCT scans were registered to the planned CT images for BMF change determination and setup displacement measurement. Independent t-tests compared setup displacement between the two groups in left-right (LR), superior-inferior (SI), and anterior-posterior (AP) directions, as well as the BMF changes. The impact of daily BMF changes on setup displacement was evaluated using multivariate logistic regression and 10-fold cross-validation.

RESULTS

The setup displacement for TM-BB in the LR, SI, and AP directions were 0.31 ± 0.25, 0.58 ± 0.40, and 0.19 ± 0.18 cm, respectively, while VBC-BB showed 0.19 ± 0.15, 0.26 ± 0.22, and 0.36 ± 0.29 cm in the corresponding directions, respectively. Margins of planning target volume (PTV) for TM-BB were 8, 10, and 6 mm in LR, SI, and AP directions, while VBC-BB showed margins of 5,7, and 8 mm, respectively. The daily BMF changes for both groups were ranked in descending order as follows: sacral rotation angle (RS), hip lateral diameter (HLD), and hip anterior-posterior diameter (HAPD). HAPD was the main factor affecting setup displacement in both the AP and SI directions in TM-BB, while RS was the primary factor for setup displacement in the AP direction in VBC-BB.

CONCLUSION

Compared with TM-BB, VBC-BB had a larger AP displacement but smaller in LR and SI displacement. Daily changes in BMF have distinct effects on setup displacement in different immobilization devices. Image-guided radiation therapy (IGRT) is highly recommended and BMF changes should be given consideration during radiotherapy.

Long-Term Outcomes in Patients With Locally Advanced Rectal Cancer Following R1 Resection After Either Induction Chemotherapy and Chemoradiotherapy or Chemoradiotherapy Alone

INTRODUCTION

Total neoadjuvant treatment (TNT) with induction chemotherapy (ICT) followed by chemoradiotherapy (CRT) has improved long-term outcomes for patients with locally advanced rectal cancer (LARC). However, long-term outcomes have not been investigated for patients with incomplete (R1) resection separately. This study investigates overall survival (OS), disease-free survival (DFS) and local and distant recurrence rates in patients with R1 resection after preoperative treatment with ICT and CRT or CRT.

PATIENTS AND METHODS

From the NORD database 689 patients with LARC who received treatment between 2006 and 2017 were screened for inclusion. All patients with R1 resection were included. ICT consisted of at least 1 cycle of capecitabine and oxaliplatin (CAPOX) and was followed by radiotherapy concomitant with capecitabine.

RESULTS

Among 46 patients with R1 resection, 27 (59%) received both ICT and CRT, and 19 (41%) patients received CRT. The 5-year OS was 44% (95% CI, 26%-63%) (ICT + CRT) versus 37% (95% CI, 15%-59%) (CRT) (P = .25) and 5-year DFS was 44% (95% CI, 26%-63%) (ICT + CRT) versus 32% (95% CI, 11%-53%) (CRT) (P = .22). The local recurrence rates showed a small nonstatistical significant difference in local control in the ICT group: 15% compared to 26% in the CRT group (P = .22). Distant recurrence rates were similar: 41% (ICT + CRT) versus 47% (CRT) (P = .48).

CONCLUSION

There was no significant difference in OS, DFS or local and distant recurrence rates between patients who received ICT + CRT versus patients who received CRT only.