Fluorouracil-based adjuvant chemotherapy after preoperative chemoradiotherapy in rectal cancer: long-term results of the EORTC 22921 randomised study

Pathologic Outcomes of Short-Course and Long-Course Radiotherapy for Locally Advanced Rectal Cancers Treated With Total Neoadjuvant Therapy

INTRODUCTION

Total neoadjuvant therapy (TNT) for patients with locally advanced rectal cancer (LARC) is now the standard of care. Randomized trials suggest the use of short-course radiotherapy (SCRT) and long-course radiotherapy (LCRT) are oncologically equivalent.

OBJECTIVE

To describe pathologic outcomes after surgical resections of patients receiving SCRT versus LCRT as part of TNT for LARC.

PARTICIPANTS

All patients with LARC treated at a single tertiary hospital who underwent proctectomy after completing TNT were included. Patients were excluded if adequate details of TNT were not available in the electronic medical record.

RESULTS

A total of 53 patients with LARC were included. Thirty-nine patients (73.5%) received LCRT and 14 (26.4%) received SCRT. Forty-nine patients (92.5%) were clinical stage III (cN1-2) prior to treatment. The average lymph node yield after proctectomy was 20.9 for SCRT and 17.0 for LCRT (P = .075). Of the 49 patients with clinically positive nodes before treatment, 76.9% of those who received SCRT and 72.2% of those who received LCRT achieved pN0 disease after TNT. Additionally, there were no significant differences in rates of pathologic complete response between patients who received SCRT and LCRT, 7.1% and 12.8%, respectively (P = .565).

CONCLUSION

Pathologic outcomes of patients with LARC treated with SCRT or LCRT, as part of TNT, may be similar. Further prospective trials are needed to assess long-term clinical outcomes and to determine best treatment protocols.

Pathologic Complete Response, Total Neoadjuvant Therapy and the Survival Paradox in Locally Advanced Rectal Cancer

BACKGROUND

Pathologic complete response (pCR) after preoperative chemoradiation (nCRT) correlates with improved overall survival for patients with locally advanced rectal cancers (LARCs). Escalation protocols including total neoadjuvant therapy (TNT), which delivers multi-agent chemotherapy and chemoradiation before surgery, are associated with increased complete response rates. However, TNT is not associated with improved overall survival. The authors hypothesized that the route to pCR may be an important predictor of oncologic outcome.

METHODS

Adults with LARC between 2006 and 2017 were identified in the National Cancer Database. The cohort was limited to those who received neoadjuvant radiation (45-70 Gy) and underwent proctectomy.

RESULTS

Of 25,880 patients, 16 % received TNT and 84 % had nCRT followed by either multi-agent (27 %), single-agent (14 %), or no adjuvant chemotherapy (44 %). Overall, 18 % achieved pCR, with higher rates in the TNT cohort than in the nCRT (18 %) or multi-agent (14 %) chemotherapy cohorts. With control for covariates, the OS in the pCR cohort was similar for the patients that received single-agent therapy and those that received multi-agent adjuvant therapy, and superior to the TNT and no adjuvant therapy cohorts. Conversely, among the patients who did not achieve pCR, those who received single-agent chemotherapy had OS comparable with those who had multi-agent adjuvant therapy and TNT, which was better than no adjuvant therapy.

CONCLUSION

Patients achieving pCR after TNT had worse OS than those who had CRT alone, suggesting that the neoadjuvant route by which pCR is achieved is prognostically relevant. Therefore, in the era of neoadjuvant therapy escalation, pCR does not necessarily portend a uniformly favorable prognosis.

"Defendit Numerus": A Pooled Analysis of 6145 Locally Advanced Rectal Cancer Treated with Preoperative Chemoradiotherapy

Objective: The optimal management of rectal cancer remains a subject of ongoing research. This meta-analysis of individual patient data assessed the benefit of chemoradiotherapy (fluorouracil-based) in local advanced rectal cancer: disease-free survival and overall survival. Methods: We pooled the data of 6145 patients from 24 studies of rectal cancer who received neoadjuvant radiotherapy with concomitant fluorouracil or capecitabine and surgery. The PRISMA 2020 abstract checklist was followed. Individual participant survival was reconstructed with an algorithm from published Kaplan-Meier curves. Results: The median OS was not reached; the mean survival time was 135.4 months (127.9-141.5). The median DFS was 176.9 months, and the mean disease-free survival time was 122.6 months (111.7-131.9). Conclusions: We provided a benchmark for future studies on rectal cancer treatment. The present results can be used in decision-making for locally advanced rectal cancer patients.

Clinical Outcomes in T4 and/or N2 Rectal Cancer Treated With Neoadjuvant Chemoradiotherapy: A Retrospective Study

INTRODUCTION

Total neoadjuvant therapy (TNT) in the management of locally advanced rectal cancer (LARC) did not show survival benefit over the standard long course chemoradiotherapy. Trials of TNT did not address the impact of each risk feature in isolation from other high-risk features.

METHODOLOGY

In this retrospective study, we describe the clinical outcomes of patients with T4 and/or N2 rectal adenocarcinoma who were treated with chemoradiotherapy followed by total mesorectal excision (TME). After obtaining the local regulatory approvals, demographic and clinical data were collected for patients in Manitoba between January 2007 and December 2019.

RESULTS

The cohort included 331 patients. 61 patients had T4-only disease and 218 had N2-only disease. Mean age was 59.65 years. 74.3% received adjuvant chemotherapy (ACT), but only 56.5% completed the planned course. R0 resection was achieved in 93.4% of patients (78.7% and 97.2% in T4 and N2, respectively). Median follow up was 4.93 years. 3-year overall recurrence rate was 29%. 3-year locoregional recurrence (LRR) rate was 8% (16% and 6% in T4 and N2, respectively). 3-year overall survival (OS) rate was 84% in the whole cohort (72.6% and 87.1% in T4 and N2, respectively). Incomplete surgical resection was a poor prognostic factor for both OS and LRR. ACT was associated with a survival benefit in the whole cohort (P = .001) and in the N2 sub-cohort (P = 003) but there was no survival benefit observed in T4 sub-cohort. ACT did not have an impact on LRR.

CONCLUSIONS

Achieving R0 resection in LARC with neoadjuvant therapy improves recurrence and survival rates. T4 disease carries a worse clinical outcome than N2 and consideration should be given to upstage T4 to stage III. Different high-risk features in LARC predict different clinical outcomes. In the era of TNT, personalization of treatment strategy based on these factors could potentially improve outcomes.

A nomogram for predicting the overall survival in rectal cancer patients after total neoadjuvant therapy

BACKGROUND

Total neoadjuvant therapy (TNT) has been recommended by the National Comprehensive Cancer Network for treating locally advanced rectal cancer (LARC), but extremely rare studies have focused on establishing nomograms to predict the prognosis in these patients after TNT. We aimed to develop a nomogram to predict overall survival (OS) in rectal cancer patients who underwent TNT.

METHODS

In retrospective cohort study, we extract the data of the rectal cancer patients from the SEER database between 2010 and 2015, including demographic information and tumor characteristics. The cohort was divided into training set and validation set based on a ratio of 7:3. Univariate logistic regression analysis was utilized for the comparison of variables in training set. Candidate variables with P < 0.1 in training set was entered into the best subset selection, LASSO regression and Boruta feature selection. Finally, the selected variables significantly associated with the 3-year, 5-year, and 8-year OS were used to build a nomogram, followed by validation using receiver operating characteristic (ROC) curve, area under the curve (AUC), and calibration curve.

RESULTS

A total of 3265 rectal cancer patients (training set: 2285; test set: 980) were included in the present study. A nomogram was developed to predict the 3-year, 5-year, and 8-year OS based on age, household income, total number of in situ/malignant tumors, CEA, T stage, N stage and perineural invasion. The nomogram showed good efficiency in predicting the 3-year, 5-year and 8-year OS with good AUC for the training set and test set, respectively.

CONCLUSION

We established a nomogram for predicting the 3-year, 5-year, and 8-year OS of the rectal cancer patients, which showed good prediction efficiency for the OS after TNT.

Current State of Neoadjuvant Therapy for Locally Advanced Rectal Cancer

ABSTRACT

In locally advanced rectal cancer, neoadjuvant treatment has evolved from no preoperative treatment to the addition of radiation and systemic therapy and ultimately total neoadjuvant therapy. Total neoadjuvant therapy is the completion of preoperative radiation or chemoradiation and chemotherapy before surgery in order to maximize tumor response and improve survival outcomes. This review summarizes the literature of the neoadjuvant approaches related to locally advanced rectal cancer and highlights the nuances of selecting the appropriate treatment.

The multidisciplinary management of locally advanced rectal cancer

INTRODUCTION

The classic paradigm for the management of locally advanced rectal cancer (LARC) consists of (chemo)radiotherapy (C)RT), total mesorectal excision, and adjuvant chemotherapy (CHT). At present, due to the high rate of distant metastasis (up to 30%), the total neoadjuvant therapy (TNT) with the administration of systemic CHT in the neoadjuvant setting has gained acceptance as standard of care.Our aim is to critically review the current literature on LARC management and summarize the different approaches recently proposed to improve clinical outcomes. It represents a starting step to develop an effective strategy that ultimately could harmonize the standard of care in daily clinical practice.

AREAS COVERED

Studies reporting the impact of TNT approaches were deemed eligible. De-escalation strategies, including non-operative management (NOM) after TNT, as well as RT omission or systemic therapy alone, were also investigated.

EXPERT OPINION

The year 2020 has seen promising new data from randomized phase III trials in the field of LARC management. Nowadays, TNT strategy has been accepted as the primary treatment for LARC. The role of de-escalation strategies is still unknown. The goal is to achieve better survival outcomes with improving quality of life. Only selected patients are likely to benefit from NOM or immunotherapy alone.

Stage IV Rectal Cancer and Timing of Surgical Approach

Liver metastases are seen in at least 60% of patients with colorectal cancer at some point during the course of their disease. The management of both primary and liver disease is uniquely challenging in rectal cancer due to competing treatments and complex sequence of treatments depending on the clinical presentation of disease. Recently, several novel concepts are shaping new treatment paradigms, including changes in timing, sequence, and duration of therapies combined with potential deescalation of treatment components. Overall, the treatment of this clinical scenario mandates multidisciplinary evaluation and personalization of care; however, there is still considerable debate regarding the timing of liver metastasectomy in the context of the overall treatment plan. Herein, we will discuss the current literature on management of rectal cancer with synchronous liver metastasis, current treatment approaches with respect to chemotherapy, and role of hepatic artery infusion therapy.

Outcome of Patients with Locally Advanced Rectal Cancer Pursuing Non-Surgical Strategy in National Cancer Database

BACKGROUND

Survival data on patients with locally advanced rectal cancer (LARC) undergoing non-operative management (NOM) in a real-world setting are lacking.

METHODS

We analyzed LARC patients from the National Cancer Database with the following features: treated between 2010 and 2020, age 18-65 years, Charlson comorbidity index (CCI) ≤ 1, received neoadjuvant multiagent chemotherapy plus radiation ≥ 45 Gray, and underwent surgery or NOM. Patients were stratified into two groups: (A) clinical T1-3 tumors with positive nodes (cT1-3N+) and (B) clinical T4 tumors, N+/- (cT4N+/-). We performed a comparative analysis of overall survival (OS) with NOM versus surgery by the Kaplan-Meier method and propensity score matching. Additionally, a multivariable analysis explored the association between NOM and OS.

RESULTS

NOM exhibited significantly lower OS than surgery in both groups. In cT1-3N+ patients, NOM resulted in a 5-year OS of 73.9% (95% confidence interval [CI] = 69.7-77.6%) versus 84.5% (95% CI = 83.6-85.3%) with surgery (p < 0.001). In the cT4N+/- group, NOM yielded a 5-year OS of 44.5% (95% CI = 37.0-51.8%) versus 72.5% (95% CI = 69.9-74.8%) with surgery (p < 0.001). Propensity score matching and multivariable analyses revealed similar conclusions.

CONCLUSION

Patients with LARC undergoing NOM versus surgery in real-world settings appear to have inferior survival.

Oncological Outcomes and Response Rate After Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer: A Network Meta-Analysis Comparing Induction vs. Consolidation Chemotherapy vs. Standard Chemoradiation

TNT is now considered the preferred option for stage II-III locally advanced rectal cancer (LARC). However, the prognostic benefit and optimal sequence of TNT remains unclear. This network meta-analysis (NMA) compared short- and long-term outcomes amongst patients with LARC receiving total neoadjuvant therapy (TNT) as induction (iTNT) or consolidation chemotherapy (cTNT) with those receiving neoadjuvant chemoradiation (nCRT) alone. A systematic literature search was performed between 2012 and 2023. A Bayesian NMA was conducted using a Markov Chain Monte Carlo method with a random-effects model and vague prior distribution to calculate odds ratios (OR) with 95% credible intervals (CrI). The surface under the cumulative ranking (SUCRA) curves were used to rank treatment(s) for each outcome. In total, 11 cohorts involving 8360 patients with LARC were included. There was no significant difference in disease-free survival (DFS) and overall survival (OS) amongst the 3 treatments. Compared with nCRT, both cTNT (OR 2.36; 95% CrI, 1.57-3.66) and iTNT (OR 1.99; 95% CrI, 1.44-2.95) significantly improved complete response (CR) rate. Notably, cTNT ranked as the best treatment for CR (SUCRA 0.90) and iTNT as the best treatment for 3-year DFS and OS (SUCRA 0.72 and 0.87, respectively). Both iTNT and cTNT strategies significantly improved CR rates compared with nCRT. cTNT was ranked highest for CR rates, while iTNT was ranked highest for 3-year survival outcomes. However, no other significant differences in DFS, OS, sphincter-saving surgery, R0 resection and postoperative complications were found amongst the treatment groups.

Treatment of Locally Advanced Rectal Cancer in the Era of Total Neoadjuvant Therapy: A Systematic Review and Network Meta-Analysis

Importance

Treatment of locally advanced rectal cancer (LARC) involves neoadjuvant chemoradiotherapy plus total mesorectal excision and adjuvant chemotherapy. However, total neoadjuvant therapy (TNT) protocols (ie, preoperative chemotherapy in addition to radiotherapy) may allow better adherence and early treatment of distant micrometastases and may increase pathological complete response (pCR) rates.

Objective

To assess the efficacy and tolerability of TNT protocols for LARC.

Data Sources

MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science Core Collection electronic databases and ClinicalTrials.gov for unpublished studies were searched from inception to March 2, 2024.

Study Selection

Randomized clinical trials including adults with LARC who underwent rectal resection as a final treatment were included. Studies including nonoperative treatment (watch-and-wait strategy), treatments other than rectal resection, immunotherapy, or antiangiogenic agents were excluded. Among the initially identified studies, 2.9% met the selection criteria.

Data Extraction and Synthesis

Two authors independently screened the records and extracted data. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA)-compliant pairwise and network meta-analyses with a random-effects model were performed in a frequentist framework, and the certainty of evidence was assessed according to the confidence in network meta-analysis approach.

Main Outcomes and Measures

The primary outcome was pCR, defined as the absence of residual tumor at pathological assessment after surgery. Secondary outcomes included tolerability, toxic effects, perioperative outcomes, and long-term survival.

Results

Of 925 records identified, 27 randomized clinical trials, including 13 413 adults aged 18 years or older (median age, 60.0 years [range, 42.0-63.5 years]; 67.2% male) contributed to the primary network meta-analysis. With regard to pCR, long-course chemoradiotherapy (L-CRT) plus consolidation chemotherapy (relative risk [RR], 1.96; 95% CI, 1.25-3.06), short-course radiotherapy (S-RT) plus consolidation chemotherapy (RR, 1.76; 95% CI, 1.34-2.30), and induction chemotherapy plus L-CRT (RR, 1.57; 95% CI, 1.09-2.25) outperformed standard L-CRT with single-agent fluoropyrimidine-based chemotherapy. Considering 3-year disease-free survival, S-RT plus consolidation chemotherapy (RR, 1.08; 95% CI, 1.01-1.14) and induction chemotherapy plus L-CRT (RR, 1.12; 95% CI, 1.01-1.24) outperformed L-CRT, in spite of an increased 5-year locoregional recurrence rate of S-RT plus consolidation chemotherapy (RR, 1.65; 95% CI, 1.03-2.63).

Conclusions and Relevance

In this systematic review and network meta-analysis, 3 TNT protocols were identified to outperform the current standard of care in terms of pCR rates, with good tolerability and optimal postoperative outcomes, suggesting they should be recognized as first-line treatments.

Future direction of total neoadjuvant therapy for locally advanced rectal cancer

Despite therapeutic advancements, disease-free survival and overall survival of patients with locally advanced rectal cancer have not improved in most trials as a result of distant metastases. For treatment decision-making, both long-term oncologic outcomes and impact on quality-of-life indices should be considered (for example, bowel function). Total neoadjuvant therapy (TNT), comprised of chemotherapy and radiotherapy or chemoradiotherapy, is now a standard treatment approach in patients with features of high-risk disease to prevent local recurrence and distant metastases. In selected patients who have a clinical complete response, subsequent surgery might be avoided through non-operative management, but patients who do not respond to TNT have a poor prognosis. Refined molecular characterization might help to predict which patients would benefit from TNT and non-operative management. Specifically, integrated analysis of spatiotemporal multi-omics using artificial intelligence and machine learning is promising. Three prospective trials of TNT and non-operative management in Japan, the USA and Germany are collaborating to better understand drivers of response to TNT. Here, we address the future direction for TNT.

The role of total neoadjuvant therapy in locally advanced rectal cancer: a survey of specialists attending the All-Ireland Colorectal Cancer Conference 2022 including lead investigators of OPRA, PRODIGE-23 and RAPIDO

BACKGROUND

The treatment of locally advanced rectal cancer (LARC) has evolved following recent landmark trials of total neoadjuvant therapy (TNT)-the delivery of preoperative chemotherapy sequenced with radiation.

AIM

To assess the preferences of colorectal surgery (CRS), radiation oncology (RO) and medical oncology (MO) specialists attending the All-Ireland Colorectal Cancer Conference (AICCC) 2022 regarding the neoadjuvant management of LARC.

METHODS

A live electronic survey explored the preferred treatment approach and TNT regimen for early-, intermediate-, bad-, and advanced-risk categories of rectal cancer according to the European Society of Medical Oncology (ESMO) guidelines. The survey was preceded by an update from lead investigators of TNT trials (OPRA, PRODIGE-23 and RAPIDO), who then participated in a multidisciplinary panel discussion.

RESULTS

Ten CRS, 7 RO and 15 MO (32 of 45 specialists) participated fully in the survey resulting in a response rate of 71%. Ninety-four percent, 76% and 53% of specialists preferred a TNT approach for patients with advanced, bad, and intermediate-risk rectal cancer, respectively. A consolidation TNT regimen of long-course chemoradiotherapy followed by chemotherapy was the most preferred regimen. Upfront surgery was preferred by 77% for early-risk disease.

CONCLUSION

This survey illustrated the general acceptance of TNT by rectal cancer specialists attending the AICCC as a valuable treatment strategy for higher-risk category LARC. Whilst the treatment of LARC changes, it remains best practice to individualize care, incorporating the selective use of TNT as discussed by an MDT and in keeping with the patient's goals of care.

Total Neoadjuvant Therapy for Rectal Cancer: Which Regimens to Use?

Total neoadjuvant therapy (TNT) is a novel strategy for rectal cancer that administers both (chemo)radiotherapy and systemic chemotherapy before surgery. TNT is expected to improve treatment compliance, tumor regression, organ preservation, and oncologic outcomes. Multiple TNT regimens are currently available with various combinations of the treatments including induction or consolidation chemotherapy, triplet or doublet chemotherapy, and long-course chemoradiotherapy or short-course radiotherapy. Evidence on TNT is rapidly evolving with new data on clinical trials, and no definitive consensus has been established on which regimens to use for improving outcomes. Clinicians need to understand the advantages and limitations of the available regimens for multidisciplinary decision making. This article reviews currently available evidence on TNT for rectal cancer. A decision making flow chart is provided for tailor-made use of TNT regimens based on tumor location and local and systemic risk.

Prediction of survival after neoadjuvant therapy in locally advanced rectal cancer - a retrospective analysis

Purpose

The aim of this retrospective analysis was to determine if the response to preoperative radio(chemo)therapy is predictive for survival among patients with locally advanced rectal cancer and may act as a potential surrogate endpoint for disease free survival and overall survival.

Results

Eight hundred seventy-eight patients from five centers were analyzed. There were 304 women and 574 men; the median age was 64.7 years. 77.6% and 22.4% of patients received neoadjuvant radiochemotherapy or short-course radiotherapy, resulting in a pathological complete response in 7.3%. T-downstaging and N-downstaging occurred in 50.5% and 37% of patients after neoadjuvant therapy. In patients with T-downstaging, the 10-year DFS and 10-year OS were 64.8% and 66.8% compared to 37.1% and 45.9% in patients without T-downstaging. N-downstaging resulted in 10-year DFS and 10-year OS in 56.2% and 62.5% compared to 47.3% and 52.3% without N-downstaging. Based on routinely evaluated clinical parameters, an absolute risk prediction calculator was generated for 5-year disease-free survival, and 5-year overall survival.

Conclusion

T-downstaging and N-downstaging after neoadjuvant radiochemotherapy or short-course radiotherapy resulted in better DFS and OS compared to patients without response. Based on clinical parameters, 5-year DFS, and 5-year OS can be predicted using a prediction calculator.

Neoadjuvant treatment of colorectal cancer: comprehensive review

BACKGROUND

Neoadjuvant therapy has an established role in the treatment of patients with colorectal cancer. However, its role continues to evolve due to both advances in the available treatment modalities, and refinements in the indications for neoadjuvant treatment and subsequent surgery.

METHODS

A narrative review of the most recent relevant literature was conducted.

RESULTS

Short-course radiotherapy and long-course chemoradiotherapy have an established role in improving local but not systemic disease control in patients with rectal cancer. Total neoadjuvant therapy offers advantages over short-course radiotherapy and long-course chemoradiotherapy, not only in terms of increased local response but also in reducing the risk of systemic relapses. Non-operative management is increasingly preferred to surgery in patients with rectal cancer and clinical complete responses but is still associated with some negative impacts on functional outcomes. Neoadjuvant chemotherapy may be of some benefit in patients with locally advanced colon cancer with proficient mismatch repair, although patient selection is a major challenge. Neoadjuvant immunotherapy in patients with deficient mismatch repair cancers in the colon or rectum is altering the treatment paradigm for these patients.

CONCLUSION

Neoadjuvant treatments for patients with colon or rectal cancers continue to evolve, increasing the complexity of decision-making for patients and clinicians alike. This review describes the current guidance and most recent developments.

[An update on total neoadjuvant treatment of adenocarcinoma of the rectum]

A major advance has been made in the management of rectal cancer, with the emergence in 2021 of total neoadjuvant treatment. The main publications from the RAPIDO and PRODIGE-23 trials reported a significant improvement in progression-free survival and the pathological complete response rate. The aim of this review is to synthesize recent data on neoadjuvant treatment of rectal cancer, to explain the long-term results of the RAPIDO and PRODIGE-23 trials, and to put them into perspective, considering current advances in de-escalation strategies. The update of the 5-year survival data from the RAPIDO trial highlights an increased risk of loco-regional relapse, with 11.7% of relapses in the experimental group and 8.1% in the control group, while the update of the PRODIGE-23 trial confirms the benefits of this treatment regimen, with a significant improvement in overall survival. In addition, the results of the OPRA and PROPSPECT trials confirm the benefit of total neoadjuvant treatment with induction chemotherapy, as well as the possibility of surgical de-escalation in the OPRA trial and radiotherapy in the PROSPECT trial. The challenge for the future is to identify patients who require total neoadjuvant treatment with the aim of curative surgery to obtain a cure without local or distant relapse, and those for whom therapeutic de-escalation can be envisaged.

Tumor regression and safe distance of distal margin after neoadjuvant therapy for rectal cancer

Neoadjuvant therapy has been widely employed in the treatment of rectal cancer, demonstrating its utility in reducing tumor volume, downstaging tumors, and improving patient prognosis. It has become the standard preoperative treatment modality for locally advanced rectal cancer. However, the efficacy of neoadjuvant therapy varies significantly among patients, with notable differences in tumor regression outcomes. In some cases, patients exhibit substantial tumor regression, even achieving pathological complete response. The assessment of tumor regression outcomes holds crucial significance for determining surgical approaches and establishing safe margins. Nonetheless, current research on tumor regression patterns remains limited, and there is considerable controversy surrounding the determination of a safe margin after neoadjuvant therapy. In light of these factors, this study aims to summarize the primary patterns of tumor regression observed following neoadjuvant therapy for rectal cancer, categorizing them into three types: tumor shrinkage, tumor fragmentation, and mucinous lake formation. Furthermore, a comparison will be made between gross and microscopic tumor regression, highlighting the asynchronous nature of regression in the two contexts. Additionally, this study will analyze the safety of non-surgical treatment in patients who achieve complete clinical response, elucidating the necessity of surgical intervention. Lastly, the study will investigate the optimal range for safe surgical resection margins and explore the concept of a safe margin distance post-neoadjuvant therapy.

MRI-based Multiregional Radiomics for Pretreatment Prediction of Distant Metastasis After Neoadjuvant Chemoradiotherapy in Patients with Locally Advanced Rectal Cancer

RATIONALE AND OBJECTIVES

To develop and validate a nomogram based on intratumoral and peritumoral radiomics signatures for pretreatment prediction of distant metastasis-free survival (DMFS) in patients after neoadjuvant chemoradiotherapy (NCRT) with locally advanced rectal cancer (LARC).

MATERIALS AND METHODS

This retrospective study included 230 patients (161 training cohort; 69 validation cohort) with LARC who underwent NCRT and surgery. Radiomics features were extracted on T2-weighted images from gross tumor volume (GTV) and volumes of 4-mm, 6-mm, and 8-mm peritumoral regions (PTV4, PTV6, and PTV8). The least absolute shrinkage and selection operator (LASSO)-Cox analysis were used for features selection and models construction. The performance of each model in predicting DMFS was evaluated by the Concordance index (C-index) and time-independent receiver operating characteristic curve (ROC).

RESULTS

The PTV4 radiomics model demonstrated superior performance compared to the PTV6 and PTV8 radiomics models, with C-indexes of 0.750 and 0.703 in the training and validation cohorts, respectively. The nomogram was constructed by integrating the GTV radiomics signature, PTV4 radiomics signature, and relevant clinical characteristics, including CA19-9 level, clinical T stage, and clinical N stage. The nomogram achieved C-indexes of 0.831 and 0.748, with corresponding AUCs of 0.872 and 0.808 for 5-year DMFS in the training and validation cohorts, respectively. Kaplan-Meier analysis revealed that a cut-off value of 1.653 effectively stratified patients into high- and low-risk groups for DM (P < 0.001).

CONCLUSION

The intra-peritumoral radiomics nomogram is a favorable tool for clinicians to develop personalized systemic treatment and intensive follow-up strategies to improve patient prognosis.

Neoadjuvant Short- Vs. Long-Course Radiation for Locally Advanced Rectal Cancer: How to Choose

OPINION STATEMENT

Over the past decades, the treatment of locally advanced rectal cancer has evolved dramatically due to improvements in diagnostic imaging, surgical technique, and the addition of radiotherapy and/or chemotherapy. Fractionation of neoadjuvant radiotherapy with or without concurrent chemotherapy remains the subject of discussion and the question multiple recent trials have aimed to answer. In light of recent data and concern for locoregional recurrence, our institution favors long-course chemoradiation in most cases, especially in low-lying primaries, threatened circumferential resection margin, consideration of non-operative management, or if the surgeon has concerns for resectability. Exceptions would include cases of oligometastatic disease planned for metastasectomy in which curative-intent treatment was pursued or if additional factors required a reduction in treatment time.

Prediction of liver metastasis and recommended optimal follow-up nursing in rectal cancer

We aimed to analyze and investigate the clinical factors that influence the occurrence of liver metastasis in locally advanced rectal cancer patients, with an attempt to assist patients in devising the optimal imaging-based follow-up nursing. Between June 2011 and May 2021, patients with rectal cancer at our hospital were retrospectively analyzed. A random survival forest model was developed to predict the probability of liver metastasis and provide a practical risk-based approach to surveillance. The results indicated that age, perineural invasion, and tumor deposit were significant factors associated with the liver metastasis and survival. The liver metastasis risk of the low-risk group was higher at 6-21 months, with a peak occurrence time in the 15th month. The liver metastasis risk of the high-risk group was higher at 0-24 months, with a peak occurrence time in the 8th month. In general, our clinical model could predict liver metastasis in rectal cancer patients. It provides a visualization tool that can aid physicians and nurses in making clinical decisions, by detecting the probability of liver metastasis.

Total Neoadjuvant Therapy (TNT) with Full Dose Concurrent Chemotherapy in Locally Advanced Rectal Adenocarcinoma Including Signet Ring and Mucinous Cancers

PURPOSE

Total neoadjuvant therapy (TNT) with pre-operative chemotherapy and chemoradiotherapy results in improved survival and is becoming the new standard of care in locally advanced rectal cancer (LARC). We describe our experience with TNT consisting of induction chemotherapy followed by chemoradiotherapy using full dose 5FU without oxaliplatin.

METHODS

Adults with biopsy-proven, newly diagnosed LARC with high-risk characteristics on pelvic MRI (T4a or T4b, extramural vascular invasion, N2, mesorectal fascia involvement, enlargement/tumor deposits on lateral lymph nodes) were included. The TNT protocol comprised of six biweekly courses of modified FOLFOX6 followed by pelvic RT with four concurrent cycles of biweekly 5-FU 2600 mg/m2 + LV 200 mg/m2 without oxaliplatin to complete 20 uninterrupted weeks of full dose 5FU. Surgery was planned 11-13 weeks after completing chemoradiotherapy.

RESULTS

Eighty-four LARC patients, including 26% with signet-ring cell carcinoma, with high-risk MRI characteristics were treated with the TNT protocol with a 96% completion rate. Significant (> grade 3) toxicities included neutropenia (23.8%), diarrhea (14.2%) anemia (10.7%), and two deaths. The median DFS at 2 years was 22.5 months with better survival noted for those who underwent surgery or had cCR (with NOM) compared to those who did not undergo surgery (due to progression, inadequate regression, or patient preference despite residual disease) -mDFS 27.7 months versus 11.4 months, p =  < 0.0001 and mOS 29.2 months versus 15 months p =  < 0.0001.

CONCLUSION

The hybrid TNT regimen was administered without significant dose delays or interruptions. Toxicity was manageable but with two treatment-related deaths. Ability to undergo surgery after TNT predicted for improved DFS and OS.

The role of adjuvant chemotherapy in rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy

Background

Neoadjuvant chemoradiotherapy has emerged as the established treatment for locally advanced rectal cancer. Nevertheless, there remains a debate regarding the necessity of adjuvant chemotherapy for patients with locally advanced rectal cancer who exhibit a favorable tumor response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery. Thus, the objective of this study is to investigate the impact of adjuvant chemotherapy on the oncological prognosis of rectal cancer patients who have a good response to neoadjuvant chemoradiotherapy.

Materials and methods

The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Articles were searched in the Web of Science, PubMed, and Cochrane Library databases. The primary outcomes assessed were 5-year overall survival, disease-free survival, cancer-specific survival, recurrence-free survival, local recurrence, and distant metastasis. The data was summarized using a random effects model.

Results

A meta-analysis was conducted using 18 retrospective studies published between 2009 and 2023. The studies included 9 from China and 5 from Korea, involving a total of 6566 patients with ypT0-2N0 rectal cancer after neoadjuvant chemoradiotherapy. The pooled data revealed that adjuvant chemotherapy significantly improved 5-year overall survival (OR=1.75, 95% CI: 1.15-2.65, P=0.008), recurrence-free survival (OR=1.73, 95% CI: 1.20-2.48, P=0.003), and reduced distant metastasis (OR=0.68, 95% CI: 0.51-0.92, P=0.011). However, adjuvant chemotherapy did not have a significant effect on disease-free survival, cancer-specific survival, and local recurrence in ypT0-2N0 rectal cancer. Subgroup analysis indicated that adjuvant chemotherapy was beneficial in improving overall survival for ypT1-2N0 rectal cancer (OR=1.89, 95% CI: 1.13-3.19, P=0.003).

Conclusion

The findings of the meta-analysis suggest that adjuvant chemotherapy may provide benefits in terms of oncological outcomes for rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy and radical surgery. However, further prospective clinical studies are needed to confirm these findings.

Optimization of treatment strategies based on preoperative imaging features and local recurrence areas for locally advanced lower rectal cancer after lateral pelvic lymph node dissection

Purpose

Local recurrence (LR) is the main cause of treatment failure in locally advanced lower rectal cancer (LALRC). This study evaluated the preoperative risk factors for LR in patients with LALRC to improve the therapeutic strategies.

Patients and Methods

LALRC patients who underwent total mesorectal excision (TME) with lateral pelvic lymph node (LPN) dissection (LPND) from January 2012 to December 2019 were reviewed. The log-rank test was used to assess local recurrence-free survival (LRFS), and multivariate Cox regression was used to identify the prognostic risk factors for LRFS. Follow-up imaging data were used to classify LR according to the location.

Results

Overall, 376 patients were enrolled, and 8.8% (n=33) of these patients developed LR after surgery. Multivariate analysis identified positive clinical circumferential resection margin (cCRM) as an independent prognostic factor for LRFS (HR: 4.94; 95% CI, 1.75-13.94; P=0.003). The most common sites for LR were the pelvic plexus and internal iliac area (PIA) (54.5%), followed by the central pelvic area (CPA) (39.4%) and obturator area (OA) (6.1%). Following a subgroup analysis, LR in the OA was not associated with positive cCRM. Patients treated with upfront surgery (n=35, 14.1%) had a lower cCRM positive rate when compared with patients treated with neoadjuvant chemoradiotherapy (nCRT) (n=12, 23.5%). However, the LR rate in the nCRT group was still lower (n=28, 36.4%) than that in the upfront surgery group (n=35, 14.%). Among patients with positive cCRM, the LR rate in patients with nCRT remained low (n=3, 10.7%).

Conclusion

Positive cCRM is an independent risk factor for LR after TME plus LPND in LALRC patients. LPND is effective and adequate for local control within the OA regardless of cCRM status. However, for LALRC patients with positive cCRM, nCRT should be considered before LPND to further reduce LR in the PIA and CPA.

Feasibility, Indications, and Prognostic Significance of Selective Lateral Pelvic Lymph Node Dissection After Preoperative Chemoradiotherapy in Middle/Low Rectal Cancer: Results of a Multicenter Lateral Node Study in China

BACKGROUND

Lateral pelvic lymph node dissection after preoperative chemoradiotherapy can decrease local recurrence to lateral compartments, thereby providing survival benefits.

OBJECTIVE

The safety of lateral pelvic lymph node dissection after preoperative chemoradiotherapy was investigated, and the surgical indications and survival benefits of lateral pelvic lymph node dissection were established on the basis of preoperative characteristics.

DESIGN

A multicenter retrospective study.

SETTINGS

Three hospitals in China.

PATIENTS

Four hundred nine patients with clinical evidence of lateral pelvic lymph node metastasis.

INTERVENTIONS

Patients who received lateral pelvic lymph node dissection were divided into 2 groups depending on whether they received chemoradiotherapy (n = 139) or not (n = 270).

MAIN OUTCOME MEASURES

The safety, indications, and survival benefits of lateral pelvic lymph node dissection after preoperative chemoradiotherapy were investigated.

RESULTS

The surgery times were significantly prolonged by preoperative chemoradiotherapy (291.3 vs 265.5 min; p = 0.021). Multivariate analysis demonstrated that poor/mucinous/signet-ring adenocarcinoma (OR = 4.42, 95% CI, 2.24-11.27; p = 0.031) and postchemoradiotherapy lateral pelvic lymph node short-axis diameter ≥7 mm (OR = 15.2, 95% CI, 5.89-53.01; p < 0.001) were independent predictive factors for lateral pelvic lymph node metastasis. Multivariate prognostic analysis showed that swollen lateral pelvic lymph nodes beyond the obturator or internal iliac as well as the involvement of 3 or more lateral pelvic lymph nodes were independent adverse prognostic factors.

LIMITATIONS

The retrospective nature of the study and the small sample size were the limitations of this study.

CONCLUSIONS

Preoperative chemoradiotherapy combined with lateral pelvic lymph node dissection is a practicable procedure with acceptable morbidity. Postchemoradiotherapy lateral pelvic lymph node short-axis diameter ≥7 mm and poor/signet/mucinous adenocarcinoma could be used for predicting lateral pelvic lymph node metastasis after chemoradiotherapy. However, lateral pelvic lymph node dissection should be carefully considered in patients with swollen lateral pelvic lymph nodes beyond the obturator or internal iliac region or involvement of multiple lateral pelvic lymph nodes. See Video Abstract at http://links.lww.com/DCR/C133 .

VIABILIDAD, INDICACIONES E IMPORTANCIA PRONSTICA DE LA DISECCIN SELECTIVA DE GANGLIOS LINFTICOS PLVICOS LATERALES DESPUS DE QUIMIORRADIOTERAPIA PREOPERATORIA EN CNCER DE RECTO MEDIO/INFERIOR RESULTADOS DE UN ESTUDIO MULTICNTRICO DE GANGLIOS LATERALES EN CHINA

ANTECEDENTES:La disección de los ganglios linfáticos pélvicos laterales después de la quimiorradioterapia preoperatoria puede disminuir la recurrencia local en los compartimentos laterales, lo que brinda beneficios de supervivencia.OBJETIVO:Se investigó la seguridad de la disección de los ganglios linfáticos pélvicos laterales después de la quimiorradioterapia preoperatoria, y se establecieron las indicaciones quirúrgicas y los beneficios de supervivencia de la disección de los ganglios linfáticos pélvicos laterales en función de las características preoperatorias.DISEÑO:Estudio retrospectivo multicéntrico.ESCENARIO:Tres hospitales en China.PACIENTES:Cuatrocientos nueve pacientes con evidencia clínica de metástasis en los ganglios linfáticos pélvicos laterales.INTERVENCIONES:Los pacientes que recibieron disección de ganglios linfáticos pélvicos laterales se dividieron en dos grupos dependiendo de si recibieron quimiorradioterapia (n = 139) o no (n = 270).PRINCIPALES MEDIDAS DE RESULTADO:Se investigaron la seguridad, las indicaciones y los beneficios de supervivencia de la disección de los ganglios linfáticos pélvicos laterales después de la quimiorradioterapia preoperatoria.RESULTADOS:Los tiempos de cirugía se prolongaron significativamente con la quimiorradioterapia preoperatoria (291,3 vs 265,5 min, p = 0,021). El análisis multivariable demostró que el adenocarcinoma mal diferenciado/mucinoso/en anillo de sello (odds ratio = 4,42, intervalo de confianza del 95%, 2,24-11,27; p = 0,031) y el diámetro del eje corto de los ganglios linfáticos pélvicos laterales después de la quimiorradioterapia ≥7 mm (odds ratio = 15,2, intervalo de confianza del 95%, 5,89-53,01; p < 0,001) fueron factores predictivos independientes de metástasis en los ganglios linfáticos pélvicos laterales. El análisis pronóstico multivariable mostró que la inflamación de los ganglios linfáticos pélvicos laterales más allá del obturador o la ilíaca interna, así como la afectación de tres o más ganglios linfáticos pélvicos laterales, eran factores pronósticos adversos independientes.LIMITACIONES:La naturaleza retrospectiva del estudio y el pequeño tamaño de la muestra.CONCLUSIONES:La quimiorradioterapia preoperatoria combinada con la disección de los ganglios linfáticos pélvicos laterales es un procedimiento practicable con una morbilidad aceptable. Posterior a la quimiorradioterapia, el diámetro del eje corto de los ganglios linfáticos pélvicos laterales ≥7 mm y el adenocarcinoma pobre/en sello/mucinoso podrían usarse para predecir la metástasis en los ganglios linfáticos pélvicos laterales después de la quimiorradioterapia. Sin embargo, la disección de los ganglios linfáticos pélvicos laterales debe considerarse cuidadosamente en pacientes con ganglios linfáticos pélvicos laterales inflamados más allá del obturador o de la región ilíaca interna o compromiso de múltiples ganglios linfáticos pélvicos laterales. Consulte Video Resumen en http://links.lww.com/DCR/C133 . (Traducción-Dr. Felipe Bellolio ).

Effect of adjuvant chemotherapy on the oncological outcome of rectal cancer patients with pathological complete response

BACKGROUND

Locally advanced rectal cancer is typically treated using a combination of neoadjuvant chemoradiotherapy and total mesorectal resection. While achieving pathological complete response following neoadjuvant chemoradiotherapy has been recognized as a positive prognostic factor in oncology, the necessity of adjuvant chemotherapy for locally advanced rectal cancer patients with pathological complete response after surgery remains uncertain. The objective of this meta-analysis was to examine the impact of adjuvant chemotherapy on the oncological outcomes of rectal cancer patients who attain pathological complete response after neoadjuvant chemoradiotherapy.

METHODS

This meta-analysis followed the guidelines outlined in the preferred reporting items for systematic review and meta-analysis (PRISMA). The Web of Science, PubMed, and Cochrane Library databases were systematically searched to identify relevant literature.

RESULTS

A total of 34 retrospective studies, including 9 studies from the NCBD database, involving 31,558 patients with pathological complete response rectal cancer, were included in the meta-analysis. The included studies were published between 2008 and 2023. The pooled analysis demonstrated that adjuvant chemotherapy significantly improved overall survival (HR = 0.803, 95% CI 0.678-0.952, P = 0.011), and no heterogeneity was observed (I2 = 0%). Locally advanced rectal cancer patients with pathological complete response who underwent adjuvant chemotherapy exhibited a higher 5-year overall survival rate compared to those who did not receive adjuvant chemotherapy (OR = 1.605, 95% CI 1.183-2.177, P = 0.002). However, the analysis also revealed that postoperative ACT did not lead to improvements in disease-free survival and recurrence-free survival within the same patient population. Subgroup analysis indicated that pathological complete response patients with clinical stage T3/T4, lymph node positivity, and younger than 70 years of age may benefit from adjuvant chemotherapy in terms of overall survival.

CONCLUSIONS

The findings of this meta-analysis suggest that adjuvant chemotherapy has a beneficial effect on improving overall survival among rectal cancer patients with pathological complete response. However, no such association was observed in terms of disease-free survival and recurrence-free survival.

Can neoadjuvant chemoradiotherapy before lateral pelvic lymph node dissection improve local control and prognosis in rectal cancer patients with clinically suspected lateral lymph node metastasis? A multicenter lateral node study in China

AIMS

Selective lateral pelvic lymph node (LPN) dissection (LPND) following neoadjuvant chemoradiotherapy (nCRT) for rectal cancer is widely recognized. This study aimed to determine the effects of nCRT before LPND on local control and prognosis of rectal cancer patients.

MATERIALS AND METHODS

Data were retrieved from a prospective database for rectal cancer patients with clinical LPN metastasis receiving total mesorectal excision and LPND at three institutions between January 2012 and December 2019. Selection bias was minimized using propensity score matching (PSM) and short-term and clinical outcomes were compared.

RESULTS

Patients (n = 213) were enrolled and grouped as either nCRT (n = 97) or non-nCRT (n = 116). PSM was used to identify 83 matched pairs. In the matched cohort, nCRT patients had a longer operation duration (310.6 vs. 265.0 min, P = 0.001), lower pathological LPN metastasis rate (32.5% vs. 48.2%, P = 0.040), and fewer harvested lymph nodes (22 vs. 25, P = 0.018) compared to the non-nCRT group. However, after PSM, the two groups had similar estimated overall 3-year survival (79.5% vs. 80.7%, P = 0.922), 3-year disease-free survival (66.1% vs. 65.5, P = 0.820), and 3-year local recurrence-free survival (88.6% vs. 89.7%, P = 0.927). Distant metastasis was the predominant recurrence pattern in the overall (45/58, 77.6%) and matched (33/44, 75.0%) cohorts.

CONCLUSIONS

LPND without nCRT is effective and sufficient in preventing local recurrence in patients with LPN metastases. Future prospective randomized controlled studies are warranted to confirm these findings. Since systemic metastasis is the predominant recurrence pattern in patients with LPN metastasis post-LPND, improved perioperative systemic chemotherapy is needed to prevent micrometastasis.

Quality of Surgical Outcome Reporting in Randomised Clinical Trials of Multimodal Rectal Cancer Treatment: A Systematic Review

INTRODUCTION

Randomised controlled trials (RCTs) continue to provide the best evidence for treatment options, but the quality of reporting in RCTs and the completeness rate of reporting of surgical outcomes and complication data vary widely. The aim of this study was to measure the quality of reporting of the surgical outcome and complication data in RCTs of rectal cancer treatment and whether this quality has changed over time.

METHODS

Eligible articles with the keywords ("rectal cancer" OR "rectal carcinoma") AND ("radiation" OR "radiotherapy") that were RCTs and published in the English, German, Polish, or Italian language were identified by reviewing all abstracts published from 1982 through 2022. Two authors independently screened and analysed all studies. The quality of the surgical outcome and complication data was assessed based on fourteen criteria, and the quality of RCTs was evaluated based on a modified Jadad scale. The primary outcome was the quality of reporting in RCTs and the completeness rate of reporting of surgical results and complication data.

RESULTS

A total of 340 articles reporting multimodal therapy outcomes for 143,576 rectal cancer patients were analysed. A total of 7 articles (2%) met all 14 reporting criteria, 13 met 13 criteria, 27 met from 11 to 12 criteria, 36 met from 9 to 10 criteria, 76 met from 7 to 8 criteria, and most articles met fewer than 7 criteria (mean 5.5 criteria). Commonly underreported criteria included complication severity (15% of articles), macroscopic integrity of mesorectal excision (17% of articles), length of stay (18% of articles), number of lymph nodes (21% of articles), distance between the tumour and circumferential resection margin (CRM) (26% of articles), surgical radicality according to the site of the primary tumour (R0 vs. R1 + R2) (29% of articles), and CRM status (38% of articles).

CONCLUSION

Inconsistent surgical outcome and complication data reporting in multimodal rectal cancer treatment RCTs is standard. Standardised reporting of clinical and oncological outcomes should be established to facilitate comparing studies and results of related research topics.

Total neoadjuvant therapy in rectal cancer: the evidence and expectations

Current management of locally advanced rectal cancer achieves high cure rates, distant metastatic spread being the main cause of patients' death. Total neoadjuvant therapy (TNT) employs (chemo)radiotherapy and combined chemotherapy prior to surgery to improve the treatment outcomes. TNT has been shown to reduce significantly distant metastases, increase disease-free survival by 5 - 10% in 3 years, and finally also overall survival (≈ 5% in 7 years). It proved to double the rate of pathologic complete responses, making it an attractive strategy for non-operative management to avoid permanent colostomy in patients with distal tumors. In addition, it endorses adherence to the therapy due to better tolerance and, potentially, shortens its overall duration. A number of questions related to TNT remain currently unresolved including the indications, preferred radiotherapy and chemotherapy regimens, their sequence, timing of surgery, and role of adjuvant therapy. A stratified approach may be the optimal way to go.

Short-term outcomes of a prospective multicenter phase II trial of total neoadjuvant therapy for locally advanced rectal cancer in Japan (ENSEMBLE-1)

Aim

To evaluate the feasibility and safety of total neoadjuvant therapy (TNT) in patients with locally advanced rectal cancer (LARC) in Japan.

Methods

This prospective, multicenter, open-label, single-arm phase II trial was conducted at five institutions. The key eligibility criteria were age ≥ 20 years, LARC within 12 cm from the anal verge, and cT3-4N0M0 or TanyN+M0 at the time of diagnosis that enabled curative resection. Preoperative short-course radiation therapy (SCRT) 5 Gy × 5 days (total 25 Gy) + CAPOX (six courses) followed by total mesorectum excision (TME) was the treatment protocol. Non-operative management (NOM) was allowed if clinical complete response (cCR) was obtained in the preoperative evaluation. The primary endpoint was the pathological complete response (pCR) rate.

Results

Thirty patients (male, n = 26; female, n = 4; median age, 62.5 [44-74] years; cT [T2, n = 1; T3, n = 25; T4, n = 4]; cN [N0, n = 13; N1, n = 13; N2, n = 4]) were enrolled. The final analysis included 30 patients in total. The completion rates were 100% for SCRT and 83% for CAPOX. TME and NOM were performed in 20 and seven patients, respectively. pCR was observed in six patients (30% [95% CI 14.0%-50.8%]). The primary endpoint was met. pCR+cCR was observed in 13 (43.3%) patients. There were no treatment-related deaths. Grade ≥3 (CTCAE ver. 5.0) adverse events (≥20%), including diarrhea (23.3%) and neutropenia (23.3%). The median follow-up period was 15.6 (10.5-22.8) months, with no recurrence or regrowth in NOM.

Conclusions

ENSEMBLE-1 demonstrated satisfactory pCR and cCR, and well-tolerated safety of TNT for patients with LARC in Japan.

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.

Mismatch Repair system protein deficiency as a resistance factor for locally advanced rectal adenocarcinoma patients receiving neoadjuvant chemo-radiotherapy

BACKGROUND

Available data on Mismatch Repair system (MMR) deficiency are conflicting and derived from small studies. Our study aimed to evaluate the therapeutic implications of MMR status in patients with locally advanced rectal cancer (LARC).

METHODS

We retrospectively collected data from 318 patients affected by LARC treated in Italy at the Medical Oncology Units of the University Hospital of Cagliari, Istituto Nazionale dei Tumori Milan, and AOU Ospedali Riuniti Ancona. All patients underwent neoadjuvant chemoradiotherapy. The primary objective was major TRG while secondary objectives were pathological complete response, disease-free survival (DFS) and overall survival (OS).

RESULTS

One hundred sixty patients (148 pMMR and 12 dMMR) were included in the exploratory cohort and 158 (146 pMMR and 12 dMMR) were included in the validation cohort. A major TRG has been shown in 42.6% and 43.1% patients with pMMR in exploratory and validation cohort, respectively; while no major TRG have been shown in dMMR patients in both cohorts. Exploratory and validation cohorts showed a statistically significant higher mDFS in pMMR patients compared to dMMR: NR vs. 14 months and NR vs. 17 months, respectively.

CONCLUSION

Our results indicated an association between dMMR and poor response to preoperative chemoradiotherapy and they represent a hypothesis-generating data for new neoadjuvant strategies.

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.

Single-arm, phase II study of intra-arterial chemotherapy plus total neoadjuvant therapy to optimise complete response in distal rectal cancer: a study protocol

INTRODUCTION

Organ preservation is now considered an acceptable alternative option in distal rectal cancer patients with clinical complete response (cCR) after neoadjuvant chemoradiation (CRT). But the cCR rate is low and about one-third of tumour will regrow, which requires more effective local treatment. CRT combined with intra-arterial chemotherapy (IAC) might be a promising approach. Additionally, total neoadjuvant therapy using FOLFIRINOX induction chemotherapy improved survival while consolidation chemotherapy improved organ preservation. We assess whether IAC plus CRT and FOLFIRINOX consolidation chemotherapy can improve the chance of organ preservation and survival in distal rectal cancer.

METHODS AND ANALYSIS

This prospective, monocentric, open-label, single-arm phase II study will include 32 patients with cT3-4NanyM0 distal rectal adenocarcinoma. All patients will receive one cycle of IAC (irinotecan, raltitrexed and oxaliplatin), followed by CRT (50 Gy/25 fractions with concomitant capecitabine) and then with six cycles of FOLFIRINOX (leucovorin, 5-fluorouracil, oxaliplatin and irinotecan). After final evaluation, patients with cCR will receive non-operative management or surgery at their own discretion and others are mandatorily referred to surgery. Adjuvant chemotherapy with six cycles of mFOLFOX6 (leucovorin, 5-fluorouracil and oxaliplatin) will be used for patients with adverse pathological features. The primary endpoint is the rate of complete response (CR; pathological CR or sustained cCR≥2 years). The main secondary endpoints are toxicity, compliance, short-term and long-term oncological outcomes, surgical morbidity and quality of life. This protocol has been designed in accordance with the Standard Protocol Items: Recommendations for Interventional Trials 2013 guidelines.

ETHICS AND DISSEMINATION

This study was approved by the Academic and Ethics Committee of The Affiliated Hospital of Youjiang Medical University for Nationalities in March 2023. Trial results will be published in peer-reviewed international journals and on the ChiCTR website.

PROTOCOL VERSION

Registered on 18 April 2023; version #1.

TRIAL REGISTRATION NUMBER

ChiCTR2300070620.

Multimodal assessment after total neoadjuvant therapy versus standard neoadjuvant chemoradiotherapy in locally advanced rectal cancer accurately predicts complete responders

PURPOSE

This study aimed to compare local regrowth rates after total neoadjuvant therapy (TNT) versus standard neoadjuvant chemoradiotherapy (SNCRT) in locally advanced rectal cancer (LARC) patients that were strictly selected and assessed with a multimodal approach. Secondary outcomes were 4-year disease-free (DFS) and overall survival (OS) rates.

METHODS

Locally advanced rectal cancer patients without distant metastases treated at Koç Healthcare Group between January 2014 and January 2021 were included. Patients were assessed for complete response with a combination of digital rectal exam, endoscopy, and magnetic resonance imaging with a dedicated rectum protocol. The systemic evaluation was performed with an upper abdomen MRI using intravenous hepatobiliary contrast agent and a thorax CT.

RESULTS

Of the 270 patients with LARC, 182 fulfilled the inclusion criteria. Ninety-seven (53.3%) underwent TNT, while 85 (46.7%) underwent SNCRT. A cumulative combination of pathological and sustained clinical complete response was significantly higher in the TNT group than in the SNCRT (45.4% vs. 20.0%, p < 0.0001). After a median follow-up of 48 months, seven patients in the W&W group had regrowth [TNT: 4 (10.8%) vs. SNCRT: 3 (23.1%), p = 0.357]. Based on pathological examination, complete/near complete mesorectum rates (p = 1.000) and circumferential resection margin positivity rates (p = 1.000) were similar between the groups. The 4-year DFS and OS rates were comparable. The patients with clinical or pathological complete response had significantly longer overall survival (p = 0.017) regardless of the type of neoadjuvant treatment.

CONCLUSIONS

Multimodal assessment after TNT effectively detects complete responders, resulting in low local recurrence and increased cumulative complete response rates. However, these outcomes did not translate into a survival advantage.

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.

Management and pharmacotherapy of pediatric colorectal carcinoma: a review

INTRODUCTION

Colorectal carcinoma (CRC) is one of the most common tumors in adult, but is extremely rare in children. In childhood, CRC often presents unfavorable aggressive histotypes, advanced clinical stage at onset and a worse prognosis. Pediatric CRC series are limited and include few patients, therefore information about treatment strategy and pharmacotherapy is scarce. For this reason, management of these patients represents a real challenge for pediatric oncologists.

AREAS COVERED

The authors provide an overview of the general features and management strategies of pediatric CRC with specific attention to systemic treatment. Literature data regarding pharmacotherapy in published pediatric series are summarized and analyzed in detail, according to adult treatment standards.

EXPERT OPINION

In the absence of specific recommendations for pediatric CRC, the general therapeutic strategy should follow the same principles as for adults and should be the result of a multidisciplinary discussion. Patient access to optimal treatment is difficult due to the lack of new drugs approved for the pediatric age group and non-availability of clinical trials. Collaboration between pediatric and adult oncologists is considered crucial in order to overcome these issues and find solutions to increase knowledge and improve the outcome of such a rare disease in children.

Neoadjuvant chemoradiotherapy with capecitabine based regimen in locally advanced rectal cancer: A retrospective study

Capecitabine-based neoadjuvant chemoradiotherapy (nCRT) is the standard treatment for locally advanced rectal cancer. The objective of this study is to analyze overall survival (OS), disease-free survival (DFS) and prognostic factors of patients with stage II to III rectal cancer treated with nCRT in our institution. Between March 2014 to June 2020, 121 locally advanced rectal cancer patients were retrospectively reviewed and analyzed. All of the enrolled patients were treated with capecitabine-based nCRT (pelvic radiotherapy: 45-50.4 Gy, 1.8 Gy/d plus concomitant capecitabine-based chemotherapy), total mesorectal excision surgery (surgery was carried out 8-12 weeks after the end of CRT), and capecitabine-based adjuvant chemotherapy. We examined the pathological complete response rate, 3-year OS, 3-year DFS and the other prognostic factors. Kaplan-Meier method and Log-rank test were used to estimate and compare survival rate. With a median follow-up of 36 months, 3-year DFS and 3-year OS was 74.4% and 83.2%, respectively. Among the 121 patients, 24 achieved pathological complete remission (19.8%). After multivariate analysis, ypTNM stage (TNM stage after neoadjuvant therapy) was significantly associated with DFS. Positive mesorectal fasciae (MRF) status on magnetic resonance imaging and ypTNM stage were significantly related to OS. CRT with capecitabine based regimen provides high rates of survival and sphincter preservation with acceptable toxicity. YpTNM stage was significantly associated with DFS; magnetic resonance imaging MRF status and ypTNM stage were significant factors for OS after multivariate analysis. Distant metastasis is the dominant mode of treatment failure, and it is crucial to optimize systemic treatment for newly diagnosed patients.

Synergistic Effect of Ginsenoside Rh2 Combines with Ionizing Radiation on CT26/luc Colon Carcinoma Cells and Tumor-Bearing Animal Model

BACKGROUND

The local tumor control rate of colon cancer by radiotherapy is unsatisfactory due to recurrence and radioresistance. Ginsenoside Rh2 (Rh2), a panoxadiol saponin, possesses various antitumor effects.

METHODS

CT26/luc murine colon carcinoma cells and a CT26/luc tumor-bearing animal model were used to investigate the therapeutic efficacy of Rh2 combined with ionizing radiation and the underlying mechanisms.

RESULTS

Rh2 caused cell cycle arrest at the G1 phase in CT26/luc cells; however, when combined with ionizing radiation, the cells were arrested at the G2/M phase. Rh2 was found to suppress the activity of NF-κB induced by radiation by inhibiting the MAPK pathway, consequently affecting the expression of effector proteins. In an in vivo study, the combination treatment significantly increased tumor growth delay time and overall survival. Furthermore, the combination treatment significantly reduced NF-κB and NF-κB-related effector proteins, along with PD-1 receptor expression. Additionally, Rh2 administration led to increased levels of interleukin-12, -18, and interferon-γ in the mice's sera. Importantly, biochemical analysis revealed no toxicities associated with Rh2 alone or combined with radiation.

CONCLUSIONS

The combination of Rh2 with radiation may have potential as an alternative to improve the therapeutic efficacy of colorectal cancer.

Total neoadjuvant therapy with short-course radiotherapy Versus long-course neoadjuvant chemoradiotherapy in Locally Advanced Rectal cancer, Korean trial (TV-LARK trial): study protocol of a multicentre randomized controlled trial

BACKGROUND

For locally advanced rectal cancer (LARC), total neoadjuvant therapy (TNT) may enhance tumour response, reduce recurrence, and improve patient compliance compared to upfront surgery. Recent studies have shown that chemoradiotherapy (CRT) followed by consolidation chemotherapy leads to higher rate of pathologic complete response (pCR) than induction chemotherapy followed by CRT. However, an optimal TNT regimen that maximise the pCR rate and minimise toxicity has not been established. Therefore, the aim of this trial was to investigate whether preoperative short-course radiotherapy followed by chemotherapy with four cycles of CAPOX can double the pCR rate compared to a standard schedule of long-course preoperative CRT in patients with LARC.

METHODS

This is a multi-centre, prospective, open label, randomised controlled trial. Patients with clinical primary tumour stage 3 and higher or regional node-involved rectal cancer located within 10 cm from the anal verge were randomly assigned equally to short-course radiotherapy (25 Gy in 5 fractions over 1 week) followed by four cycles of CAPOX (intravenous oxaliplatin [130 mg/m2, once a day] on day 1 and capecitabine [1,000 mg/m2, twice a day] from days 1 to 14) (TNT) or CRT (50.4 Gy in 28 fractions over 5 weeks, concurrently with concomitant oral capecitabine 825 mg/m2 twice a day). After preoperative treatment, total mesorectal excision was performed 2-4 weeks in the TNT group and 6-10 weeks in the CRT group, followed by optional additional adjuvant chemotherapy. The primary endpoint is the pCR rate, and secondary endpoints include disease-related treatment failure, quality of life, and cost-effectiveness. Assuming a pCR rate of 28% and 15% in the TNT and CRT groups, respectively, and one-side alpha error rate of 0.025 and power of 80%, 348 patients will be enrolled considering 10% dropout rate.

DISCUSSION

The TV-LARK trial will evaluate the superiority of employed TNT regimen against the standard CRT regimen for patients with LARC. We aimed to identify a TNT regimen that will improve the pCR rate and decrease systemic recurrence in these patients.

TRIAL REGISTRATION

Cris.nih.go.kr ID: KCT0007169 (April 08, 2022). The posted information will be updated as needed to reflect the protocol amendments and study progress.

Feasibility and safety of lateral pelvic lymph node dissection for elderly patients with middle-low rectal cancer: results of a large multicenter lateral node collaborative group study in China

BACKGROUND

Lateral pelvic lymph node (LPN) dissection can improve local control in certain rectal cancer patients with LPN metastasis. However, the effects of this technically complex procedure on perioperative safety and long-term survival of elderly patients (≥ 70 years) remain unclear.

METHODS

Locally advanced middle-low rectal cancer patients diagnosed with LPN metastasis who underwent total mesorectal excision (TME) with LPN dissection at three institutions from January 2012 to December 2019 were included in this study. Additionally patients who had neoadjuvant chemoradiotherapy (nCRT) and those who did not were compared.

RESULTS

In total there were 407 patients, including 49 elderly and 358 non-elderly patients, of which 249 were male, with a median age of 58 years (range:18-85 years). In the whole cohort, operation time (280.7 vs. 292.0 min, p = 0.498) and estimated blood loss (100 vs. 100 ml, p = 0.384) were comparable in the elderly and non-elderly groups. There was no significant difference in the incidences of overall complications (24.5% vs. 19.8%, p = 0.448) and severe (Clavien-Dindo grade 3-5) surgical complications (8.2% vs. 7.5%, p = 0.778) between the two groups. However, the incidence of urinary retention (14.3% vs. 5.6%, p = 0.032) and intensive care unit admission (16.3% vs. 6.1%, p = 0.018) was significantly higher in the elderly group compared with those in the non-elderly group. The 3-year overall survival (88.7% vs. 82.1%, p = 0.516) and disease-free survival (81.2% vs. 70.7%, p = 0.352) were comparable between the two groups. Moreover, results in the nCRT cohort were comparable to those in the overall cohort.

CONCLUSIONS

Even with nCRT, TME combined with LPN dissection is safe and feasible for elderly patients, demonstrating low mortality and acceptable morbidity. Elderly and non-elderly patients with LPN metastasis who undergo LPN dissection can achieve comparable 3-year survival outcomes.

TRAIL REGISTRATION

ClinicalTrials.gov Identifier: NCT04850027.

Total neoadjuvant therapy in rectal cancer: a network meta-analysis of randomized trials

PURPOSE

To assess the efficacy of total neoadjuvant therapy (TNT) for rectal carcinoma in comparison with conventional chemoradiotherapy (CRT).

METHODS

A systematic review was performed according to the PRISMA guidelines. A Bayesian network meta-analysis was done using NetMetaXL and WinBUGS. This study was registered in PROSPERO on March 3, 2022 (No. CRD-42022307867).

RESULTS

Outcomes of 2,719 patients from 10 randomized trials between 2010 and 2022 were selected. Of these 1,191 (44%) had conventional long-course CRT (50-54 Gy) and capecitabine, 506 (18%) had induction chemotherapy followed by CRT (50-54 Gy) and capecitabine (iTNT), 230 (9%) had long-course CRT (50-54 Gy) followed by consolidation chemotherapy (cTNT), and 792 (29%) undergone modified short-course radiotherapy (25 Gy) with subsequent chemotherapy (mTNT). Total pathologic complete response (pCR) was 20% in the iTNT group, 21% in the mTNT group, 22% in the cTNT group, and 12% in the CRT group. Statistically significant difference in pCR rates was detected when comparing iTNT with CRT (odds ratio [OR], 1.76; 95% credible interval [CrI], 1.06-2.8), mTNT with CRT (OR, 1.90; 95% CrI, 1.25-2.74), and cTNT with CRT groups (OR, 2.54; 95% CrI, 1.26-5.08). No differences were found in R0 resection rates. No significant difference was found in long-term outcomes.

CONCLUSION

The early administration of systemic chemotherapy in the TNT regimen has improved short-term outcomes, though long-term results are underreported. Randomized trials with survival as the endpoint are necessary to evaluate the possible advantages of TNT modes.

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.

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 ).

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 ).

The Conditioning of Adjuvant Chemotherapy for Stage II and III Rectal Cancer Determined by Postoperative Pathological Characteristics in Romania

The management of locally advanced rectal cancer (LARC) suffered changes thanks to the development of improved surgical procedures, radiation delivery, and chemotherapy. Although treatment options improved individually, the optimal order is still debated. Neoadjuvant chemo-radiotherapy followed by total mesorectal excision (TME) has been the "golden standard" for locally advanced rectal cancer. There is no common ground in international guidelines on the indications of adjuvant chemotherapy (ADJCHT), with differences between the American, European, and Japanese guidelines. This paper studies the preferences of Romanian oncologists in prescribing ADJCHT. We conducted a single-institution, retrospective study of all nonmetastatic, ECOG 0-1 LARC patients staged II-III who underwent TME and were admitted to the Oncology or Radiotherapy Department of Colțea Clinical Hospital, Bucharest between January 2017 and March 2021. A total of 186 patients were included in the study. A positive correlation was found between ADJCHT and each of the following: (y)pT > 2, (y)pN > 0, and the presence of perineural invasion (PNI+). A strong positive correlation was found between ADJCHT and the presence of at least one risk factor: (y)pT > 2, (y)pN > 0, PNI+, lymphovascular invasion, positive margins, or tumor grade > 1. Tumor downstaging decreased the risk of metastases in the first 2 years and was associated with the use of neoadjuvant radiotherapy, while adding neoadjuvant chemotherapy increased the chance of nodal downstaging. ADJCHT practice for LARC in Romania follows either NCCN or ESMO guidelines, at the discretion of the oncologist, due to the lack of national guideline.

Neoadjuvant chemotherapy with modified FOLFOXIRI for locally advanced rectal cancer to transform effectively EMVI and MRF from positive to negative: results of a long-term single center phase 2 clinical trial

PURPOSE

Chemoradiotherapy (CRT) remains the standard treatment for locally advanced rectal cancer (LARC). This phase 2 clinical trial was designed to evaluate the efficacy and safety of neoadjuvant triplet chemotherapy with mFOLFOXIRI (folinic acid, 5-fluorouracil, oxaliplatin, and irinotecan) in LARC.

PATIENTS AND METHODS

The patients with LARC (the lower edge more than 5 cm from the anal verge) received up to 5 cycles of mFOLFOXIRI. MRI was performed to assess the baseline and postchemotherapy TN stage. Radical resection was performed within 4-6 weeks from the last dose of chemotherapy if the tumor shrank or remained stable. Adjuvant chemotherapy with mFOLFOX6 or XELOX was recommended. Postoperative radiation was planned for R1 resection, ypT4b, ypN2 and a positive CRM. The primary endpoint was the pathological complete response (pCR) rate.

RESULTS

From February 2016 to March 2019, 50 patients were enrolled. Forty-eight (96%) were clinically node-positive, 28 (56.5%) with MRF invasion and 39 (78.4%) were EMVI positive. The median cycle of neoadjuvant mFOLFOXIRI chemotherapy was 5 (range,1-5). A total of 46/50 (92%) patients underwent total mesorectal excision (TME) surgery, all with R0 resection. The pCR rate was 4.3% (2/46). Twenty-three of 46 (50%) patients with cN + achieved a pathological node-negative status. The proportions of pathologically positive CRM and EMVI were 2.2% and 34.7%, respectively. Adjuvant radiotherapy was given to 14/46 (30.4%) patients. The most common Grade 3 or > toxicities included neutrocytopenia (50%), leukopenia (14%) and diarrhea (12%) during the neoadjuvant chemotherapy period. Clinically meaningful postoperative complications included pneumonia (n = 1), pelvic infection (n = 1) and anastomotic fistula (n = 1). With a median follow-up time of 51.2 months, local recurrences and distant metastases were confirmed in 3 (6.5%) and 9 (19.6%) of cases, respectively. The 3-year disease free survival (DFS) and overall survival (OS)rates were 75.8% and 86.8%.

CONCLUSION

Neoadjuvant chemotherapy with mFOLFOXIRI yielded a significant down-staging effect and seemed to be effective in eliminating EMVI and transforming the positive MRF to negative in LARC. The survival results are promising. The long-term follow-up showed promising DFS and OS rates accompanied by a favorable safety profile.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03443661, 23/02/2018.

A case report of typhlitis during novel use of ropidoxuridine-capecitabine-radiotherapy for treatment-naïve rectal cancer

BACKGROUND

Rectal carcinomas are tumors that arise from the last 12 cm of the large intestine closest to the anus. They generally have a modest prognosis exacerbated by a high local recurrence rate if radiosensitizing chemotherapy is not given during radiotherapy. This case report discusses the clinical trial treatment of a patient with rectal adenocarcinoma by a new ropidoxuridine-capecitabine-radiotherapy combination. This case report is novel due to the patient's participation in an accelerated titration phase I clinical trial and the resultant rare adverse event of treatment-related sigmoid typhlitis.

CASE PRESENTATION

The patient was an 82-year-old female who noticed hematochezia and change in stool caliber over a period of 3 months. A rectal mass was identified by biopsy as a microsatellite stable adenocarcinoma. A planned total neoadjuvant treatment involved eight cycles of leucovorin calcium (folinic acid)-fluorouracil-oxaliplatin (mFOLFOX6) chemotherapy, followed by a clinical trial combination of ropidoxuridine-capecitabine-radiotherapy, prior to definitive surgery. The patient began daily intensity modulated pelvic radiotherapy with concurrent twice-daily oral ropidoxuridine and twice-daily oral capecitabine to be given over 6 weeks. After 14 days of ropidoxuridine-capecitabine-radiotherapy, the patient developed sigmoid typhlitis requiring a 10-day hospitalization and 14-day disruption of treatment. The patient died 27 days after the start of ropidoxuridine-capecitabine-radiotherapy. This adverse event was listed as a definite attribution to the ropidoxuridine-capecitabine treatment; pharmacokinetic and pharmacodynamic data showed low ropidoxuridine metabolite DNA incorporation and high capecitabine metabolite concentration. The accelerated titration phase I clinical trial has been subsequently closed to accrual (NCT04406857).

CONCLUSIONS

We believe this case report demonstrates the decision-making process for terminating a phase I accelerated titration designed clinical trial. The report also presents the rare complication of sigmoid typhlitis as a treatment-attributed adverse event. In this case, a ropidoxuridine-capecitabine combination was used as an investigational radiosensitizing treatment now with a narrower future clinical development pathway.

Total neoadjuvant therapy versus chemoradiotherapy for locally advanced rectal cancer: Bayesian network meta-analysis

BACKGROUND

Total neoadjuvant therapy is a promising treatment for locally advanced rectal cancer, utilizing either short-course radiotherapy or long-course chemoradiotherapy, but their relative efficacy remains unclear. The aim of this Bayesian network meta-analysis was to investigate clinical outcomes amongst patients receiving total neoadjuvant therapy with short-course radiotherapy or long-course chemoradiotherapy, and those receiving long-course chemoradiotherapy alone.

METHODS

A systematic literature search was performed. All studies that compared at least two of these three treatments for locally advanced rectal cancer were included. The primary endpoint was the pathological complete response rate, and survival outcomes were adopted as secondary outcomes.

RESULTS

Thirty cohorts were included. Compared with long-course chemoradiotherapy, both total neoadjuvant therapy with long-course chemoradiotherapy (OR 1.78, 95 per cent c.i. 1.43 to 2.26) and total neoadjuvant therapy with short-course radiotherapy (OR 1.75, 95 per cent c.i. 1.23 to 2.50) improved the pathological complete response rate. Similar benefits were observed in the sensitivity and subgroup analyses, except for short-course radiotherapy with one to two cycles of chemotherapy. No significant differences in survival outcomes were found amongst the three treatments. Long-course chemoradiotherapy with consolidation chemotherapy (HR 0.44, 95 per cent c.i. 0.20 to 0.99) exhibited higher disease-free survival than long-course chemoradiotherapy alone.

CONCLUSION

Compared with long-course chemoradiotherapy, both short-course radiotherapy with greater than or equal to three cycles of chemotherapy and total neoadjuvant therapy with long-course chemoradiotherapy can improve the pathological complete response rate, and long-course chemoradiotherapy with consolidation chemotherapy may lead to a marginal benefit in disease-free survival. The pathological complete response rate and survival outcomes are similar for total neoadjuvant therapy with short-course radiotherapy or long-course chemoradiotherapy.