Neoadjuvant Modified FOLFOX6 With or Without Radiation Versus Fluorouracil Plus Radiation for Locally Advanced Rectal Cancer: Final Results of the Chinese FOWARC Trial

Optimizing total neoadjuvant therapy in locally advanced rectal cancer: risk stratification should not be overlooked

Chemoradiotherapy plus total mesorectal excision has been established as the standard treatment for locally advanced rectal cancer (LARC) and can achieve satisfactory local control. However, systemic control of LARC, especially in patients with risk factors for poor prognosis, is still of concern. As application of total neoadjuvant therapy (TNT) has been proposed as a potential solution, a clearer risk stratification of LARC to guide individual treatment is needed. Combination therapy such as targeted therapy or immunotherapy can be used to increase treatment intensity for high-risk LARC. In this review, we evaluate recent trials of several treatment modalities, specifically focusing on intensified TNT regimens for high-risk LARC with the goal of summarizing optimal clinical strategies and future study designs.

Associations of pretreatment emotional distress with adherence to therapy for patients with locally advanced rectal cancer: a post hoc analysis of the Chinese FOWARC phase 3 randomized clinical trial

BACKGROUND

Non-adherence in advanced rectal cancer therapy is common and severely impairs clinical outcomes. Although behavioral research suggests emotional factors influence adherence, limited evidence links pretreatment emotional distress (PED) to treatment adherence in rectal cancer patients.

METHODS

This post hoc analysis of a phase 3 randomized clinical trial was conducted from June 9, 2010, to February 15, 2015, involving 219 patients (assigned to receive neoadjuvant therapy with fluorouracil plus radiotherapy [group A, 67 patients], modified fluorouracil, leucovorin, and oxaliplatin [mFOLFOX6] plus radiotherapy [group B, 66 patients], or mFOLFOX6 alone [group C, 86 patients] followed by TME resection and postoperative adjuvant chemotherapy) with locally advanced rectal cancer from the main center. The PED of patients was measured through the emotional dimension items in the Quality of Life Questionnaire-Core Questionnaire (QLQ-C30). The primary outcome was adherence to therapy, with non-adherence defined as patients in groups A and B receiving fewer than ten cycles of chemotherapy or less than 37 Gy of radiotherapy, and patients in group C receiving fewer than ten cycles of chemotherapy. Multivariable logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for adherence by PED levels. Additionally, the structural equation model (SEM) was utilized to analyze the impact pathways of PED on adherence.

RESULTS

Among the 219 patients (142 men; mean age, 53.4 years) who completed the QLQ-C30 scale, 27.8% (61/219) demonstrated non-adherence to the treatment regimen. Multivariable analyses showed that each 1-point increase in PED score raised non-adherence risk by 4.37 times (OR: 4.37, 95% CI: 1.92-9.96, P < 0.001). The SEM analysis revealed that PED score was positively correlated with the risk of non-adherence (standardized regression coefficients [β] = 0.25, 95% CI: 0.11 to 0.28), while economic burden was positively correlated with PED (β = 0.17, 95% CI: 0.11 to 0.28), and could indirectly affect adherence through PED (β = 0.04, 95% CI: 0.01 to 0.09).

CONCLUSIONS

Higher levels of pretreatment emotional distress were associated with an increased risk of treatment non-adherence, thereby highlighting the potential significance of addressing emotional distress in cancer management.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01211210.

TRIM29 promotes liver metastasis via enhancing hepatic colonization by stabilizing FAM83H to regulate keratin network in colorectal cancer

Liver metastasis is a frequent and severe event of colorectal cancer (CRC), and patients with liver metastases typically exhibit poor prognosis, high recurrence rates and low responsiveness to treatment. However, the precise molecular mechanisms underlying the liver metastasis in CRC remain poorly understood. In this study, through a comprehensive multi-omics approach, we here identify CRC cells with high tripartite motif-containing protein 29 (TRIM29) expression as the critical subset responsible for liver metastasis. Omics-sequencing pathway analyses combined with in vitro functional assays revealed that CRC cells expressing high TRIM29 expression displayed enhanced cell adhesion, proliferation and liver metastasis capabilities. Mechanistically, TRIM29 interacts with FAM83H and stabilizes it by reducing its ubiquitination and degradation, thereby redistributing cellular keratins, which activates the NF-κB pathway and upregulates PLXNB2 expression to enhance cell adhesion and proliferation to promote hepatic colonization and drive CRC liver metastasis. Interestingly, TRIM29 upregulates the expression of PLXNB2 that can bind to the hepatocyte-specific ligand SEMA4G. Importantly, targeting TRIM29-FAM83H-elicited keratin redistribution and PLXNB2 elevation effectively abrogated CRC liver metastasis. Our findings position TRIM29 as a central driver of liver metastasis in CRC and highlight its potential as a therapeutic target for reducing the risk of liver metastasis in patients.

Transcatheter rectal arterial chemoembolization with oxaliplatin and concurrent chemoradiotherapy in patients with locally advanced rectal cancer: A retrospective comparative study

BACKGROUND

The aim of the study is to assess whether transcatheter rectal arterial chemoembolization (TRACE) with oxaliplatin could increase the pathologic complete response (pCR) rate of locally advanced rectal cancer (LARC) and improve survival outcomes, while minimizing adverse events compared to preoperative chemoradiotherapy (CRT) alone.

METHODS

Eligible LARC patients who received TRACE with oxaliplatin plus chemoradiotherapy (the NATRACE-CRT group) or preoperative CRT alone (the NA-CRT group) were retrospectively selected from the database of our institution. Pathological results, treatment-related adverse events and survival in the two groups were compared.

RESULTS

A total of 236 patients were enrolled. The pCR rates were 18.38 % in the NATRACE-CRT group and 14.00 % in the NA-CRT group, with a non-significant difference of 4.38 % (P = 0.473). The median follow-up time was 42 months. The 5-year DFS (75.7 % vs. 73.2 %; P = 0.879) and OS (73.4 % vs. 70.3 %; P = 0.855) rates were comparable between the NATRACE-CRT group and the NA-CRT group. However, the NATRACE-CRT group had significantly fewer patients achieving TRG3 compared to the NA-CRT group (16.18 % vs. 35.00 %; P = 0.001). Furthermore, TRG3 patients in the NATRACE-CRT group exhibited significantly longer OS compared to those in the NA-CRT group (5-year OS: 88.9 % vs 59.5 %; P = 0.016).

CONCLUSIONS

TRACE with oxaliplatin demonstrates potential in improving treatment response and prognosis of LARC patients with chemoradiotherapy resistance.

The Landmark Series: Neoadjuvant Therapy for Locally Advanced Rectal Cancer

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

NUPR1 Promotes Radioresistance in Colorectal Cancer Cells by Inhibiting Ferroptosis

Radioresistance is a major clinical challenge and the underlying mechanism has not been thoroughly elucidated. In this study, a radioresistant (RR) cell line is established to explore the transcriptomic signatures of radioresistance in colorectal cancer (CRC). KEGG enriched pathway analysis demonstrated that ferroptosis is inactivated in RR cells. Further detection confirmed that radiotherapy can promote ferroptosis, and ferroptosis inactivation is one of the hallmarks of radioresistance in CRC. What's more, induction of ferroptosis can restore the radiosensitivity of CRC cells. Then, we performed RNA sequencing to compare gene expression between parental and RR cells, and cells pretreated with or without RSL3. Via high-throughput screening, NUPR1 was identified as a potential candidate for ferroptosis-mediated radioresistance in CRC. CRC cells can acquire radiation resistance by NUPR1-mediated ferroptosis suppression in the NUPR1-overexpressing cell line. More importantly, ZZW-115, an NUPR1 inhibitor, can sensitise RR cells to radiotherapy. Overall, our findings identify ferroptosis inactivation linked with resistance to radiotherapy. Besides, NUPR1 can promote radiation resistance by inhibiting ferroptosis, and targeting NUPR1 may be a potential strategy to relieve radioresistance associated with ferroptosis in CRC.

A multicentre prospective single-arm clinical trial to evaluate the treatment outcomes of prophylactic laparoscopic lateral pelvic lymph node dissection for advanced lower rectal cancer

AIM

There has been no prospective multicentre validation of the treatment outcomes of minimally invasive lateral pelvic lymph node dissection for lower rectal cancer; hence, this prospective study aimed to evaluate the treatment outcomes of prophylactic laparoscopic lateral pelvic lymph node dissection.

METHOD

Between May 2018 and August 2021, 90 patients with Stage II-III rectal cancer were registered. The clearance range for lateral pelvic lymph node dissection included the lymph nodes around the internal iliac artery and the obturator lymph nodes, while the autonomic nerves were generally preserved. The primary outcome was the incidence of Grade III-IV postoperative complications at discharge. The secondary outcomes were surgical and pathological outcomes, urinary function, sexual function, disease-free survival and overall survival. The experience of each facility and surgeon requirements were set to maintain quality control of lateral pelvic lymph node dissection.

RESULTS

Of the 90 patients, 87 were analysed after exclusion of ineligible patients. There were 30 and 57 cases, respectively, of Stage II and III rectal cancer, among which 17 patients underwent neoadjuvant chemotherapy. The median operating time and blood loss were 472 min and 55 mL, respectively. Postoperative complications were observed in 22 patients (25.3%), and the primary outcome of Grade III postoperative complication was observed in five patients (5.7%). Eight lateral lymph nodes were harvested bilaterally, and lateral lymph node metastasis was observed in 14 patients.

CONCLUSION

Prophylactic lateral pelvic lymph node dissection can be safely performed with adequately quality-controlled laparoscopic procedures.

[For Whom, How and to What End - Neoadjuvant Therapy for Rectal Cancer?]

Over the past few decades, considerable progress has been made in the treatment of rectal cancer, leading to a reduction in local recurrence rates and an improvement in prognosis. The current German S3 guideline on colorectal cancer recommends neoadjuvant therapy for UICC stage II and III tumours of the middle and lower rectum. Primary surgery is still recommended for UICC I tumours, although exceptions are being discussed for certain subgroups, such as cT1/2 tumours with questionable nodal involvement. Current trials are focusing on multimodality treatment concepts, in particular total neoadjuvant therapy (TNT), which has been examined in several phase II and phase III trials. Therapies with selective omission of neoadjuvant radiotherapy and organ-preserving approaches are also being investigated. This review provides a comprehensive overview of the current evidence on neoadjuvant treatment of rectal cancer, highlights new multimodal treatment approaches, and discusses future challenges and opportunities to optimise treatment according to stage and to provide patients with the best possible individualised treatment.

Radiation Therapy for Rectal Cancer: An ASTRO Clinical Practice Guideline Focused Update

PURPOSE

With the results of several recently published clinical trials, this guideline focused update provides evidence-based recommendations for the indications and dose-fractionation regimens for neoadjuvant radiation therapy (RT), optimal sequencing of RT and systemic therapy in the context of total neoadjuvant therapy (TNT), and considerations for selective omission of RT and surgery for rectal cancer.

METHODS

The American Society for Radiation Oncology convened a multidisciplinary task force to update 3 key questions that focused on the role of RT for patients with operable rectal cancer. The key questions addressed (1) indications for neoadjuvant RT, (2) selection of neoadjuvant regimens, and (3) indications for consideration of a nonoperative management (NOM) or local excision approach after definitive/preoperative chemoradiation. Recommendations were based on a systematic literature review and created using a predefined consensus-building methodology and system for quality of evidence grading and strength of recommendation.

RESULTS

For patients with stage II-III rectal cancer, neoadjuvant RT was strongly recommended; however, among patients deemed at lower risk of locoregional recurrence, consideration of omission of neoadjuvant RT was conditionally recommended in favor of neoadjuvant chemotherapy with a favorable treatment response or upfront surgery. For patients with T3-T4 and node-positive rectal cancer undergoing neoadjuvant RT, a TNT approach was strongly recommended. Among patients with higher risk of locoregional recurrence, TNT with chemotherapy before or after long-course chemoradiation was strongly recommended, whereas TNT with short-course RT followed by chemotherapy was conditionally recommended. For patients with rectal cancer for whom NOM is a priority, concurrent chemoradiation followed by consolidation chemotherapy was strongly recommended. Selection of RT dose-fractionation regimen, sequencing of therapies, and consideration of NOM should be determined by multidisciplinary consensus and based on disease extent, disease location, patient preferences, and quality of life considerations.

CONCLUSIONS

The task force proposed recommendations to inform best clinical practices on the use of RT for rectal cancer with strong emphasis on multidisciplinary care. Future studies should focus on further addressing optimal treatment regimens to allow for more personalized recommendations based on individual risk stratification and patient priorities regarding quality of life.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of colorectal cancer, 2024 update

The 2024 updates of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for the diagnosis and treatment of colorectal cancer emphasize standardizing cancer treatment in China, highlighting the latest advancements in evidence-based medicine, healthcare resource access, and precision medicine in oncology. These updates address disparities in epidemiological trends, clinicopathological characteristics, tumor biology, treatment approaches, and drug selection for colorectal cancer patients across diverse regions and backgrounds. Key revisions include adjustments to evidence levels for intensive treatment strategies, updates to regimens for deficient mismatch repair (dMMR)/ microsatellite instability-high (MSI-H) patients, proficient mismatch repair (pMMR)/ microsatellite stability (MSS) patients who have failed standard therapies, and rectal cancer patients with low recurrence risk. Additionally, recommendations for digital rectal examination and DNA polymerase epsilon (POLE)/ DNA polymerase delta 1 (POLD1) gene mutation testing have been strengthened. The 2024 CSCO Guidelines are based on both Chinese and international clinical research, as well as expert consensus, ensuring their relevance and applicability in clinical practice, while maintaining a commitment to scientific rigor, impartiality, and timely updates.

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

BACKGROUND

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Modern rectal cancer management: A review of total neoadjuvant therapy and current practices

Total Neoadjuvant Therapy (TNT) is a promising strategy for treating locally advanced rectal cancer (LARC) and has started to replace the traditional neoadjuvant chemoradiotherapy (CRT). This review combines findings from pivotal studies that helped TNT to integrate into clinical practice. It emphasizes the efficacy of TNT in improving the disease-free and metastasis-free survival, pathologic complete response and, according to recent studies, a potential improvement in overall survival when compared to standard CRT. In addition, the review analyzes increased organ preservation by TNT and explores the trend towards personalized medicine with the use of TNT. Additionally, it investigates the possibility of excluding radiotherapy in some subgroups. Future directions include integration of immunotherapy, use of TNT in early-stage disease and determining optimal components of TNT, such as type of chemotherapy and type of radiotherapy.

Daxx Variation as a Potential Predictive Marker of the Therapeutic Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

OBJECTIVE

The response to neoadjuvant chemoradiotherapy (NACRT) for locally advanced rectal cancer (LARC) varies from achieving a complete pathological response to encountering resistance to treatment. Therefore, biomarkers for predicting the NACRT responses should be identified. This prospective study aimed to identify key genomic biomarkers as the predictors of the NACRT response with LARC.

METHODS

Overall, 67 patients with LARC treated with NACRT and proctectomy were divided into two groups based on the tumor regression grade (TRG) for identifying key biomarkers. Patients with a TRG of 0 or 1 were assigned to the sensitive response group, and patients with a TRG of 2 or 3 were the resistant response group. Twenty-nine postsurgical tumor samples were collected for whole exome sequencing (WES) to identify genomic variation biomarkers. The other 38 pairs of tumor specimens from pretreatment and postsurgery samples were evaluated by immunohistochemistry (IHC) to examine the biomarker features.

RESULTS

In the WES subcohort, 11 genes showed copy number variation, including FNKBIA, ARID1A, CCND2, CDK4, LYN, MDM2, RAD51B, RARA, SPEN, STAT3, and Daxx, which has the highest copy number variation. For the IHC subcohort, Daxx was initially highly expressed in the nuclei of tumor cells, particularly in the sensitive response group, while varying its expression after NACRT, demonstrating that Daxx levels were related to treatment responses and the survival benefit, especially a better disease-free survival (DFS).

CONCLUSION

We identified multiple genomic variations between sensitive and resistant responders and verified that Daxx is a potential predictive biomarker of the response to NACRT in LARC.

Evaluation of the effectiveness of using capecitabine versus capecitabine combined with oxaliplatin during preoperative radiotherapy for patients with rectal cancer: A retrospective cohort study

The purpose of this study was to assess and compare the clinical effectiveness of capecitabine monotherapy and that of capecitabine combined with oxaliplatin as neoadjuvant chemoradiotherapy during preoperative radiotherapy in the management of low and middle rectal cancer. A retrospective cohort study was performed. Medical data were collected from individuals with locally progressing low and middle rectal cancer admitted to a regional hospital in China. Two groups of patients were formed for different chemoradiotherapy regimens: the oxaliplatin group and the capecitabine monotherapy group. Within the oxaliplatin group, the CAPEOX regimen was applied for 2 rounds during radiotherapy, intravenous infusion of oxaliplatin was administered 1 day prior to radiotherapy. In the capecitabine monotherapy group, capecitabine was implemented once daily during radiotherapy, and no medication was taken without radiotherapy. A total of 260 patients were included in the study. When oxaliplatin is administered concurrently with preoperative radiation therapy for patients with locally progressing low and middle rectal cancer, the pathologic complete remission rate can be considerably increased without appreciably increasing adverse effects or impairing postoperative recovery. On the other hand, the long-term effectiveness against metastasis and/or recurrence showed no discernible benefit.

Neoadjuvant Modified Infusional Fluorouracil, Leucovorin, and Oxaliplatin With or Without Radiation Versus Fluorouracil Plus Radiation for Locally Advanced Rectal Cancer: Updated Results of the FOWARC Study After a Median Follow-Up of 10 Years

We present 10-year results of the phase Ⅲ FOWARC trial, which evaluated the efficacy of modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) with or without radiation compared with fluorouracil with radiation in patients with locally advanced rectal cancer. A total of 495 patients age 18-75 years with stage Ⅱ-Ⅲ rectal cancer were randomly assigned to three treatment arms: fluorouracil plus radiotherapy, mFOLFOX6 plus radiotherapy, or mFOLFOX6 alone, followed by surgery and adjuvant chemotherapy. With a median follow-up of 10 years, the 10-year disease-free survival (DFS) rates were 52.5%, 62.6%, and 60.5%, respectively (P = .56). The 10-year locoregional recurrence (LR) rates were 10.8%, 8.0%, and 9.6% (P = .57), and the 10-year overall survival (OS) rates were 65.9%, 72.3%, and 73.4% (P = .90). Subgroup analysis identified ypTNM stage as a significant prognostic factor for DFS, LR, and OS (P < .0001, P < .006, P < .0001, respectively). Patients achieving pathologic complete response had 10-year DFS, LR, and OS rates of 84.3%, 3.0%, and 92.4%, respectively. No significant difference was observed in long-term survival outcome between mFOLFOX6 with and without radiation and fluorouracil plus radiation. These results demonstrate that neoadjuvant mFOLFOX6 chemotherapy can be considered as a therapeutic option in LARC.

Predictive value of rectal MRI variables for pathological complete response in locally advanced rectal cancer following neoadjuvant chemoradiotherapy

PURPOSE

To evaluate the predictive value of MRI-determined variables for pathological complete response (pCR) in locally advanced rectal cancer (LARC) patients following neoadjuvant chemoradiotherapy (NCRT).

METHODS

Clinical data were collected from patients who received NCRT between January 2019 and 2022. Patients with rectal adenocarcinoma, cT3-4N0, or TanyN1-2 were included. pCR was defined pT0N0. Patients were divided into pCR and non-pCR group. Logistic regression analysis was performed to identify factors associated with pCR. A nomogram model was constructed to validate its predictive ability and accuracy.

RESULTS

A total of 585 patients were identified, with 144 (24.6%) in the pCR group and 441 (75.4%) in the non-pCR group. Patients with mrT2-3 (OR 6.41, P < 0.001), mrN0 (OR 2.17, P < 0.001), circumferential occupation range < 1/2 cycles (OR 2.11, P < 0.001), tumor vertical diameter < 36 mm (OR 2.10, P < 0.001), negative mesorectal fascia (OR 3.21, P < 0.001), and extramural vascular invasion (OR 5.68, P < 0.001) were more likely to achieve higher pCR rates. Logistic regression analysis revealed that mrT2-3 (OR 3.50, P < 0.001), tumor vertical diameter < 36 mm (OR 2.57, P < 0.001), and negative extramural vascular invasion (OR 4.03, P < 0.001) were independent protective factors for pCR. A nomogram was developed to predict pCR, achieving a C-index of 0.778.

CONCLUSION

Patients with mrT2-3, tumor vertical diameter < 36 mm, and negative extramural vascular invasion are more likely to achieve pCR after NCRT.

Bibliometric analysis of preoperative radiotherapy for locally advanced rectal cancer: evolution and future

Background

Preoperative radiotherapy of rectal cancer has been a hot topic of research in recent years with the introduction of total neoadjuvant therapies and immunotherapeutic agents. We utilized bibliometrics and visualization analysis to examine studies in this field, aiming to identify current hotspots and research trends.

Method

We searched the Web of Science database for all publications related to preoperative radiotherapy of rectal cancer in the past 10 years. Using bibliometric analysis software, such as VOSviewer, CiteSpace and R-studio, we extracted and analyzed the data, summarizing the publication output of countries, institutions, authors, and journals in this field, and analyzing their relationships. We also summarized the keywords, burst words, and most cited articles, and analyzed the relationships among them.

Results

We found 794 publications in the field, sourced from 217 journals or books, involving 5,805 authors from various organizations and countries. Through bibliometric analysis, we observed a growing trend in the number of publications in preoperative radiotherapy of rectal cancer over the past 10 years. China, United States and Italy were the top countries in terms of publication output. Sun Yat-sen University, Fujian University, and Fudan University were the top three medical centers in terms of publication output, while Leiden University from Netherlands led globally in terms of citation impact. Professor Zhen Zhang, Sanjun Cai, and Ji Zhu were the top three authors with the highest publication output. The most highly cited journals in this field includes "The Lancet Oncology," "J Clinical Oncology," and "Annals of Oncology." Journals such as "Radiotherapy and Oncology," "Frontiers in Oncology," and "BMC Cancer" have the highest number of articles published. Based on the analysis of keywords and burst words, we found that "preoperative chemoradiation" and "oral capecitabine" were the research hotspots before 2016, while the focus shifted to "short-course radiotherapy" and "long-term outcomes" after 2017. Currently, the most frequently cited publications mainly summarize multicenter clinical studies and total neoadjuvant treatment models and immunotherapy.

Conclusion

Research on preoperative radiotherapy of rectal cancer is increasing year by year, and attracting attention from high-cited journals such as "The Lancet Oncology," "JCO," and "Annals of Oncology." Based on current data, the total neoadjuvant treatment models and radiation combined with immunotherapy are the research trends.

Short- and long-term outcomes of neoadjuvant chemotherapy compared with neoadjuvant chemoradiotherapy for locally advanced rectal cancer: an updated meta-analysis

BACKGROUND AND PURPOSE

Neoadjuvant chemoradiotherapy (NACRT) is the standard treatment regimen for locally advanced rectal cancer (LARC) but has unavoidable radiation toxicity. With the advent of more optimized chemotherapy regimens, neoadjuvant chemotherapy (NAC) is sometimes offered as an alternative to NACRT. The purpose of this meta-analysis was to compare the short- and long-term outcomes of NAC and NACRT for LARC patients.

MATERIALS AND METHODS

Eligible studies through June 15, 2023, were identified in the online databases. Short-term and long-term outcomes were synthesized. A total of 10 studies involving 14,807 patients (1714 vs. 13093) were included in this meta-analysis.

RESULTS

There were no significant differences between the two groups in terms of lymphovascular invasion, perineural invasion, R0 resection, local recurrence, overall survival, disease-free survival, or grade 3-4 adverse events. The NAC group had a lower rate of pathological complete response [OR (95% CI) = 0.61 (0.45, 0.82)] and tumor regression grade [OR (95% CI) = 0.42 (0.25, 0.70)] and a greater rate of sphincter preservation [OR (95% CI) = 1.57 (1.14, 2.16)] than did the NACRT group. In the prospective studies, no differences in pathological complete response [OR (95% CI) = 0.62 (0.35, 1.11)], tumor regression grade [OR (95% CI) = 0.72 (0.52, 1.00)], and rate of sphincter preservation [OR (95% CI) = 1.40 (0.94, 2.09)] have been found between the two groups.

CONCLUSION

NAC was able to achieve similar short- and long-term outcomes as NACRT. It is worth noting that some prospective studies excluded patients with high-risk features. For those LARC patients with high-risk features, the efficacy of NAC versus NACRT needs to be further explored.

Therapeutic Management of Locally Advanced Rectal Cancer: Existing and Prospective Approaches

Rectal cancer (RC) presents significant challenges in diagnosis and treatment, with increasing incidence among younger populations. Treatment approaches, particularly for locally advanced rectal cancer (LARC), have evolved, notably with the introduction of total neoadjuvant therapy (TNT). TNT combines neoadjuvant chemotherapy and chemoradiotherapy before surgery, improving overall survival and reducing both metastasis and local recurrence rates compared to traditional methods, while enabling more patients to complete the full oncological treatment. Clinical trials, such as RAPIDO, OPRA, and PRODIGE 23, have demonstrated the effectiveness of TNT in tumor downstaging and complete pathological responses, offering better outcomes for patients; however, debates persist regarding the role of neoadjuvant radiotherapy, with novel strategies exploring its omission in specific cases to reduce toxicity and enhance quality of life. In addition, organ preservation strategies, such as the watch-and-wait (WW) approach, have emerged as viable options for patients with a complete response to neoadjuvant therapy. Future directions point towards personalized treatment plans incorporating radiogenomics and the integration of artificial intelligence into diagnostics to optimize patient outcomes. This review aims to synthesize current treatment strategies and ongoing advancements in rectal cancer management, providing insights into potential future innovations.

Emerging therapeutic strategies in Lynch syndrome-associated colorectal cancer and the role of MMR testing

Lynch syndrome is the most common hereditary cancer predisposition, accounting for 1-5% of colorectal cancer cases, and is driven by germline mutations in DNA mismatch repair genes. Despite established diagnostic criteria, such as the Amsterdam guidelines, Lynch syndrome remains largely underdiagnosed. To address this gap, universal tumour screening has been introduced for all newly diagnosed cases of colorectal cancer and endometrial cancer, significantly improving early detection. The surgical management of colorectal cancer in patients with Lynch syndrome remains controversial. While extended colectomy reduces the risk of metachronous colorectal cancer, surgical strategies must be carefully individualised based on patient-specific factors. Chemoprevention with aspirin has shown promise in reducing the risk of colorectal cancer, with ongoing trials investigating optimal dosing. Immunotherapy, particularly immune checkpoint inhibitors, has revolutionised the treatment of Microsatellite Instability-High/deficient Mismatch Repair colorectal cancer, offering durable responses and significant survival benefits. In addition, the neoadjuvant use of immune checkpoint inhibitors is paving the way for non-surgical interventions, potentially transforming the management of colorectal cancer in patients with Lynch syndrome. A multidisciplinary approach and continued research are essential to optimise cancer prevention, treatment and quality of life for people with Lynch syndrome.

A Comprehensive Approach to Neoadjuvant Treatment of Locally Advanced Rectal Cancer

At the end of the past century, the introduction of Total Mesorectal Excision (TME), preceded by either short-course radiotherapy (SCRT) or chemoradiation (CRT), established the new standard of care for locally advanced rectal cancer (LARC). Recently, significant advancements were achieved for both dMMR/MSI and pMMR/MSS LARC patients. For the 2-3% of dMMR/MSI LARCs, ablative immunotherapy emerged as a curative approach, offering the possibility of avoiding chemotherapy (CT), radiotherapy, and surgery altogether. In pMMR/MSS LARCs, the intensification of preoperative treatments with Total Neoadjuvant Treatment (TNT) afforded three outcomes: (a) a reduction of distant metastases, positively impacting on survival endpoints, (b) a significant increase of complete clinical response (cCR) rate, paving the way for non-operative management (NOM), and (c) the selective omission of radiotherapy following induction CT. The choice of the most appropriate therapeutic strategy can only be made through the shared decision-making process between physician and patient based on risk stratification and patient preferences.

"Add More Arrows to Your Quiver": The Role of Adding Another Chemotherapy Drug to Fluoropyrimidine and Long Term Radiotherapy in Locally Advanced Rectal Cancer: A Systematic Review and Meta-Analysis

Objectives: Despite optimal local control obtained with neoadjuvant chemoradiotherapy (CRT), data on overall survival (OS) and disease-free survival (DFS) of local advanced rectal cancer patients are still equivocal. This meta-analysis aimed to estimate the pathological complete response (pCR), regression rate, DFS, and OS probabilities of rectal cancer patients treated with a second chemotherapy drug added to fluoropyrimidine and long-term radiotherapy. Methods: Computerized bibliographic searches of MEDLINE, PUBMED, Web of Science and the Cochrane Central Register of Controlled Trials databases (1970-2023) were supplemented with hand searches of reference lists. Studies were included if they were randomised controlled trials (RCTs) comparing intensified chemotherapy with CRT to preoperative CRT and if they had patients with resectable, histologically proven rectal adenocarcinoma without metastases. Results: Eighteen RCTs (7695 patients) were analysed. Data on population, intervention, and outcomes were extracted from each RCT, following the intention-to-treat method, by three independent observers and combined using the DerSimonian and Laird methods. A chemotherapy with two drug and long-term radiotherapy CRT, compared to preoperative CRT (fluoropyrimidine and long-term radiotherapy), significantly increases the rate of pathological complete response (OR 1.37 (95% CI, 1.16-1.63) p = 0.0003) and the regression rate (OR 1.57 (95% CI, 1.16-2.14) p < 0.00001). Furthermore, it increases DFS (HR 0.87 (95% CI, 0.79 to 0.95) p = 0.002 and OS HR 0.84 (95% CI, 0.74 to 0.95) p = 0.007). The risk of severe adverse events (≥G3) is increased OR 1.96 (95% CI 1.35-2.85), p = 0.0005. Conclusions: In patients with resectable rectal cancer, intensified chemotherapy can reduce by 13% the risk of disease progression and by 16% the risk of death.

A management of patients achieving clinical complete response after neoadjuvant therapy and perspectives: on locally advanced rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME) and selective use of adjuvant chemotherapy is currently considered the standard of care for locally advanced rectal cancer (LARC). Despite this, the concept of organ preservation is gradually challenging this approach. The management of complete clinical remission (cCR) lacks international consensus, leading scholars to develop their own perspectives based on well-designed studies and long-term data from large multicenter cohorts. To ensure appropriate treatment, this review focuses on the choice of neoadjuvant therapy, criteria for defining cCR, and treatment strategies for patients who achieve cCR after neoadjuvant therapy. By providing guidance on the accurate management of LARC patients after cCR, this review aims to prevent over- or under-treatment.

Efficacy and safety of combining short-course neoadjuvant chemoradiotherapy with envafolimab in locally advanced rectal cancer patients with microsatellite stability: a phase II PRECAM experimental study

BACKGROUND

Conventional neoadjuvant chemoradiotherapy (nCRT) yields a pathologic complete response (pCR) rate of 15-30% for locally advanced rectal cancer (LARC). This study ventures to shift this paradigm by incorporating short-course nCRT with immunotherapy, specifically Envafolimab, to achieve improved treatment efficacy and possibly redefine the standard of care for LARC.

MATERIALS AND METHODS

The PRECAM study is a prospective, single-arm, phase 2 clinical trial for LARC in patients with microsatellite stable (MSS) tumors. Participants received short-course radiotherapy (25Gy/5f), followed by two cycles of CAPEOX chemotherapy and six weekly doses of Envafolimab, a PD-L1 antibody, before total mesorectal excision surgery. The primary endpoint was the pCR rate.

RESULTS

From April to December 2022, 34 patients were enrolled, of whom 32 completed the study, each diagnosed with an MSS rectal adenocarcinoma. All patients underwent preoperative CRT combined with Envafolimab. Remarkably, a pCR rate of 62.5% (20/32) was attained, and a significant pathologic response rate of 75% (24/32) was achieved. Additionally, 21 of 32 participants achieved a neoadjuvant rectal (NAR) score below 8, suggesting an effective treatment response. Common adverse events included tenesmus (78.1%), diarrhea (62.5%), and leukocyte decrease (40.6%). Two Grade 3 adverse events were noted, one related to liver function abnormality and the other to a decrease in platelet count. Surgical procedures were performed in all cases, with minor complications, including ileus, infections, and anastomotic leakage. As of this report, there have been no reported cases of recurrence or death during the follow-up period, ranging from 12 to 20 months.

CONCLUSION

In LARC patients exhibiting MSS tumors, combining short-course nCRT with Envafolimab demonstrated favorable efficacy, leading to a significant pCR rate. Minor adverse effects and surgical complications were observed. These preliminary but promising results underscore the potential of this approach and call for further exploration and validation through a randomized controlled trial.

Long-term outcomes of S-1 and oxaliplatin neoadjuvant chemotherapy with total mesorectal excision and lateral lymph node dissection for rectal cancer

PURPOSE

Chemoradiotherapy (CRT) for rectal cancer is limited by its harmful side effects and its insufficient benefit on lateral lymph node metastases. The purpose of this study was to evaluate the long-term outcomes of S-1 and oxaliplatin with total mesorectal excision (TME) and lateral lymph node dissection (LLND) without radiation for rectal cancer.

METHODS

The inclusion criteria were patients with stage II or III rectal cancer located within 10 cm from the anal verge. Fifty-two patients who underwent neoadjuvant chemotherapy (NAC) followed by TME and LLND were evaluated. The primary endpoint was the 3-year local recurrence. The secondary endpoints were the 3-year rates of relapse-free survival and overall survival. Expected post-NAC and surgical outcomes were prospectively analyzed.

RESULTS

The overall recurrence rate was 15.4%, with eight patients developing distant recurrences. The local recurrence rate was 7.7% (n = 4). Among the 4 patients with local recurrence, 3 (5.8%) patients had central pelvis recurrence, and 1 (1.9%) patient had lateral pelvic recurrence. The 3-year survival rate was 98.1%, and the 3-year relapse-free survival rate was 84.6%. The risk factors for local recurrence were mucinous carcinoma (p = 0.016) and a positive resection margin (p = 0.009). Pathological mesorectal lymph node metastasis and local recurrence were independent risk factors for poor survival.

CONCLUSIONS

Although preoperative chemotherapy and TME with LLND are sufficient to control local recurrence, some cases will require more aggressive chemotherapy with radiation therapy.

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.

Review of definition and treatment of upper rectal cancer

While the treatment of locally advanced lower and middle rectal cancer with total mesorectal excision (TME) after neoadjuvant therapy is now well defined, the treatment of locally advanced upper rectal cancer (LAURC) remains controversial. Although most teams and academic societies recommend upfront surgery (US) with partial mesorectal excision (PME), as this appears to be sufficient for these tumors, the literature remains conflicting regarding the additional use of neoadjuvant therapy and TME. Current recommendations for the treatment of LAURC do not reflect actual clinical practice. Notably, there is a paucity of published data specific to the treatment of LAURC since most of the data are from sub-analyses of different cohorts. Another important point responsible for the inconsistent data situation is the fact that the current definition of upper rectal cancer is based on anatomical criteria that are difficult to reproduce and therefore also differ between international professional societies. The aim of this review is to provide a deeper insight into the issues surrounding the treatment of LAURC based on an analysis of the current literature, including anatomic and embryologic data.

Could elective nodal irradiation for locally advanced rectal cancer be omitted in the context of total neoadjuvant therapy? An analysis of the recurrence sites of rectal cancer

Purpose

This study aims to optimize neoadjuvant radiotherapy target area for locally advanced rectal cancer (LARC) patients undergoing total neoadjuvant therapy (TNT) by examining local recurrence patterns.

Methods and materials

We retrospectively analyzed the clinical data of rectal cancer patients who undergone local recurrence after surgery. Recurrence sites were categorized and compared with initial diagnosis imaging, focusing on visible and suspicious lesions.

Results

Of the 126 patients who met our criteria, 186 lesions were analyzed. Within these, 75.40% of cases (95/126) and 83.33% of lesions (155/186) were located within the pelvic cavity. Conversely, 3.97% of cases (5/126) and 3.33% of lesions (6/186) occurred outside the pelvic cavity. Additionally, 20.63% of cases (26/126) and 13.44% of lesions (25/186) were found in both regions. Recurrences were predominantly observed in mesenteric regions (MR) (40.86%, 76/186) and presacral regions (PR) (32.26%, 60/186). In addition, 86.51% of patients (109/126) had recurrent lesions in HRA and the suspected lesions areas. Further analysis showed that initial CEA levels and adjuvant therapy types were identified as independent predictors for recurrence in MR/PR and initially suspected lesions. 86.51% of patients had recurrent lesions in HRA and the suspected lesions areas.

Conclusion

The MR, PR, and areas of initial suspicious lesions are high-risk zones for post-surgical recurrence of LARC. Exploratory study of involved-field irradiation (IFI) can be carried out in the context of TNT in LARC.

Executive Summary of the American Radium Society on Appropriate Use Criteria for Nonoperative Management of Rectal Adenocarcinoma: Systematic Review and Guidelines

For patients with rectal cancer, the standard approach of chemotherapy, radiation therapy, and surgery (trimodality therapy) is associated with significant long-term toxicity and/or colostomy for most patients. Patient options focused on quality of life (QOL) have dramatically improved, but there remains limited guidance regarding comparative effectiveness. This systematic review and associated guidelines evaluate how various treatment strategies compare to each other in terms of oncologic outcomes and QOL. Cochrane and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) methodology were used to search for prospective and retrospective trials and meta-analyses of adequate quality within the Ovid Medline database between January 1, 2012, and June 15, 2023. These studies informed the expert panel, which rated the appropriateness of various treatments in 6 clinical scenarios through a well-established consensus methodology (modified Delphi). The search process yielded 197 articles that advised voting. Increasing data have shown that nonoperative management (NOM) and primary surgery result in QOL benefits noted over trimodality therapy without detriment to oncologic outcomes. For patients with rectal cancer for whom total mesorectal excision would result in permanent colostomy or inadequate bowel continence, NOM was strongly recommended as usually appropriate. Restaging with tumor response assessment approximately 8 to 12 weeks after completion of radiation therapy/chemoradiation therapy was deemed a necessary component of NOM. The panel recommended active surveillance in the setting of a near-complete or complete response. In the setting of NOM, 54 to 56 Gy in 27 to 31 fractions concurrent with chemotherapy and followed by consolidation chemotherapy was recommended. The panel strongly recommends primary surgery as usually appropriate for a T3N0 high rectal tumor for which low anterior resection and adequate bowel function is possible, with adjuvant chemotherapy considered if N+. Recent data support NOM and primary surgery as important options that should be offered to eligible patients. Considering the complexity of multidisciplinary management, patients should be discussed in a multidisciplinary setting, and therapy should be tailored to individual patient goals/values.

Essential updates 2022-2023: Surgical and adjuvant therapies for locally advanced colorectal cancer

Pivotal articles that had been published between 2022 and 2023 on surgical and perioperative adjuvant treatments for locally advanced colorectal cancer (CRC) were reviewed. This review focuses on new evidence in the following areas: optimization of surgical procedures for colon cancer, including the optimal length of bowel resection and use of the no-touch isolation technique; minimally invasive surgery for rectal cancer, such as laparoscopic transanal total mesorectal excision and robotic surgery; neoadjuvant treatments for rectal cancer, including total neoadjuvant therapy; neoadjuvant chemotherapy for colon cancer; and postoperative adjuvant chemotherapy for Stage II and III colon cancer. Although the current understanding may not enable perfect decision-making for patients and medical professionals, ongoing advancements are expected to result in more effective personalized treatment plans, ultimately improving the prognosis and quality of life of patients.

CapeOX as neoadjuvant chemotherapy for locally advanced rectal cancer: might less be more?

BACKGROUND

Locally advanced rectal cancer (LARC) poses unique challenges in treatment, with current neoadjuvant chemoradiotherapy (NA-CRT) showing limitations. The CapeOX regimen emerges as a potential less aggressive neoadjuvant chemotherapy (NAC) for LARC.

METHODS

We conducted a retrospective study involving treatment-naïve patients with LARC from March 2014 to March 2021 who received 2-4 cycles of CapeOX NAC followed by radical surgery. Treatment response was evaluated using tumor regression grade (TRG), MRI-based TRG (MRI-TRG), and Neoadjuvant Rectal (NAR) score.

RESULTS

94.7% of patients experienced symptom improvement and 96.4% achieved sphincter-preserving surgery. Post-NAC showed significant tumor regression and MRI confirmed a tumor length reduction (P < 0.001). Clinical and pathological staging discrepancies post-NAC suggest broader therapeutic advantages. 5-year overall and disease-free survival rates were 78.4% and 73.4%. NAR scores provided better prognostic accuracy than MRI-TRG.

CONCLUSION

CapeOX NAC presents notable benefits for LARC patients and its clinical significance may be underestimated. The NAR score demonstrates superior prognostic value over MRI-TRG.

Tailoring treatment for locally advanced rectal cancer

The management of locally advanced rectal cancer (LARC) requires personalized treatment to improve outcomes and maintain quality of life. This narrative review examines the recent developments in management, focusing on non-operative management, radiotherapy choices or omission, chemotherapy sequencing, and the role of immunotherapy and brachytherapy boost. Non-operative management can be an option for select patients, and the use of long-course chemoradiation (LCCRT) with consolidation chemotherapy or brachytherapy boost has been shown to enhance rectal preservation rates. For patients requiring surgery, the choice between LCCRT and SCRT depends on the risk of local recurrence and patient preferences. MSI-high LARC patients benefit significantly from single-agent immunotherapy, and early clinical trials show promising results for the application of immunotherapy in MSS tumors. By stratifying patients based on individual and tumor risk factors, clinicians can tailor treatment plans to improve oncologic outcomes and quality of life for patients with LARC.

Management of Locally Advanced Rectal Cancer: ASCO Guideline

ASCO Guidelines provide recommendations with comprehensive review and analyses of the relevant literature for each recommendation, following the guideline development process as outlined in the ASCO Guidelines Methodology Manual. ASCO Guidelines follow the ASCO Conflict of Interest Policy for Clinical Practice Guidelines.Clinical Practice Guidelines and other guidance ("Guidance") provided by ASCO is not a comprehensive or definitive guide to treatment options. It is intended for voluntary use by providers and should be used in conjunction with independent professional judgment. Guidance may not be applicable to all patients, interventions, diseases or stages of diseases. Guidance is based on review and analysis of relevant literature, and is not intended as a statement of the standard of care. ASCO does not endorse third-party drugs, devices, services, or therapies and assumes no responsibility for any harm arising from or related to the use of this information. See complete disclaimer in Appendix 1 and 2 (online only) for more.PURPOSETo provide evidence-based guidance for clinicians who treat patients with locally advanced rectal cancer.METHODSA systematic review of the literature published from 2013 to 2023 was conducted to identify relevant systematic reviews, phase II and III randomized controlled trials (RCTs), and observational studies where applicable.RESULTSTwelve RCTs, two systematic reviews, and one nonrandomized study met the inclusion criteria for this systematic review. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.RECOMMENDATIONSFollowing assessment with magnetic resonance imaging, for patients with microsatellite stable or proficient mismatch repair locally advanced rectal cancer, total neoadjuvant therapy (TNT; ie chemoradiation [CRT] and chemotherapy) should be offered as initial treatment for patients with tumors located in the lower rectum and/or patients who are at higher risk for local and/or distant metastases. Patients without higher-risk factors may discuss chemotherapy with selective CRT depending on extent of response, TNT, or neoadjuvant long-course CRT or short-course radiation. For patients who are candidates for TNT, the preferred timing for chemotherapy is after radiation, and neoadjuvant long-course CRT is preferred over short-course radiation therapy (RT), however short-course RT may also be a viable treatment option depending on circumstances. Nonoperative management may be discussed as an alternative to total mesorectal excision for patients who have a clinical complete response to neoadjuvant therapy. For patients whose tumors are microsatellite instability-high or mismatch repair deficient, immunotherapy is recommended.Additional information is available at http://www.asco.org/gastrointestinal-cancer-guidelines.

Neoadjuvant Treatment in Rectal Cancer

A major advance in rectal cancer was the evidence supporting short-course radiotherapy and long-course chemoradiotherapy. Both have been shown to improve local outcomes. Total neoadjuvant therapy (TNT) is the new kid on the block that provides further benefit of improving local responses as well as reducing systemic relapses, thus increasing overall survival. Details of the four key TNT trials are discussed. They pave the way for nonoperative management for patients who achieve clinical complete responses.

Impact of Dose-Escalated Chemoradiation on Pathological Complete Response in Patients with Locally Advanced Rectal Cancer

Locally advanced rectal cancer requires a multimodal treatment. Radiotherapy is being explored for intensification to improve the rates of pathological complete responses (ypCR rates) which are correlated with better outcomes. This study reports a comparison between standard versus escalated doses in a preoperative scenario. The ypCR rates, toxicity, postoperative complications, and disease-free and overall survival at 5 years are described. From 2012 to 2019, 99 patients were analyzed retrospectively: standard arm (mean of 47.5 Gy) vs. dose-escalated arm (mean of 54.3 Gy). All patients were treated with 3DRT in 25 fractions, with concomitant capecitabine and surgery performed according to the total mesorectal excision principles in both arms. The ypCR was reported using the "College of American Pathologist grades"; the gastrointestinal (GI) and genitourinary (GU) toxicity was reported using the "Common Terminology Criteria for Adverse Events" (CTCAE 4.0). The ypCR rates were higher in the dose-escalated group (25% vs. 10.64%; p = 0.07), with a lower rate of non-treatment response (61.36% vs. 38.64%; p = 0.11). No statistical differences between the arms were found in terms of the oncological outcomes, postoperative complications (p = 0.15), second surgeries (p = 0.62), or deaths (p = 0.62). The CTCAE acute GI and GU toxicity were grade I or II in both arms. Our study presents a long-term follow-up in comparative cohorts.

"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.

Effect of neoadjuvant chemoradiotherapy with or without PD-1 antibody sintilimab in pMMR locally advanced rectal cancer: A randomized clinical trial

Neoadjuvant chemoradiotherapy (NACRT) was the standard treatment for patients with locally advanced rectal cancer (LARC) with proficient mismatch repair (pMMR) proteins. In this randomized phase 2 trial (ClinicalTrial.gov: NCT04304209), 134 pMMR LARC patients were randomly (1:1) assigned to receive NACRT or NACRT and the programmed cell death protein 1 (PD-1) antibody sintilimab. As the primary endpoint, the total complete response (CR) rate is 26.9% (18/67, 95% confidence interval [CI] 16.0%-37.8%) and 44.8% (30/67, 95% CI 32.6%-57.0%) in the control and experimental arm, respectively, with significant difference (p = 0.031 for chi-squared test). Response ratio is 1.667 (95% CI 1.035-2.683). Immunohistochemistry shows PD-1 ligand 1 (PD-L1) combined positive score is associated with the synergistic effect. The safety profile is similar between the arms. Adding the PD-1 antibody sintilimab to NACRT significantly increases the CR rate in pMMR LARC, with a manageable safety profile. PD-L1 positivity may help identify patients who might benefit most from the combination therapy.

Racial comparisons in treatment of rectal adenocarcinoma and survival in the military health system

BACKGROUND

Racial disparities in treatment and outcomes of rectal cancer have been attributed to patients' differential access to care. We aimed to study treatment and outcomes of rectal cancer in the equal access Military Health System (MHS) to better understand potential racial disparities.

METHODS

We accessed the MilCanEpi database to study a cohort of patients aged 18 and older who were diagnosed with rectal adenocarcinoma between 1998 and 2014. Receipt of guideline recommended treatment per tumor stage, cancer recurrence, and all-cause death were compared between non-Hispanic White and Black patients using multivariable regression models with associations expressed as odds (AORs) or hazard ratios (AHRs) and their 95% confidence intervals (CIs).

RESULTS

The study included 171 Black and 845 White patients with rectal adenocarcinoma. Overall, there were no differences in receipt of guideline concordant treatment (AOR = 0.76, 95% CI = 0.45 to 1.29), recurrence (AHR = 1.34, 95% CI = 0.85 to 2.12), or survival (AHR = 1.08, 95% CI = 0.77 to 1.54) for Black patients compared with White patients. However, Black patients younger than 50 years of age at diagnosis (AOR = 0.34, 95% CI = 0.13 to 0.90) or with stage III or IV tumors (AOR = 0.28, 95% CI = 0.12 to 0.64) were less likely to receive guideline recommended treatment than White patients in stratified analysis.

CONCLUSIONS

In the equal access MHS, although there were no overall racial disparities in rectal cancer treatment or clinical outcomes between Black and White patients, disparities among those with early-onset or late-stage rectal cancers were noted. This suggests that factors other than access to care may play a role in the observed disparities and warrants further research.

mFOLFOX6 versus mFOLFOX6 + aflibercept as neoadjuvant treatment in MRI-defined T3-rectal cancer: a randomized phase-II-trial of the German Rectal Cancer Study Group (CAO/ARO/AIO 0214)

BACKGROUND

Neoadjuvant chemotherapy is an option for patients with locally advanced rectal cancer at low risk for local recurrence. This randomized phase II trial investigated whether the addition of aflibercept to modified FOLFOX6 (mFOLFOX6) could improve the rates of centrally confirmed pathological complete remissions (pCR) and (disease-free) survival in magnetic resonance imaging (MRI)-staged cT3 rectal cancer.

PATIENTS AND METHODS

Patients with rectal cancer fulfilling the following criteria were included: lower border of tumor >5 cm and <16 cm from anal verge; circumferential resection margin >2 mm and T3-tumor with a maximum infiltration of 10 mm, as determined by MRI. Patients were randomized 1 : 2 to six cycles mFOLFOX6 ± aflibercept. Surgery was scheduled 4 weeks after chemotherapy. Primary endpoint was the rate of centrally confirmed pCR. The study was designed to detect an improvement of pCR from 10% to 27% (power 80%, type I error 20%).

RESULTS

A total of 119 randomized patients started treatment (39 patients mFOLFOX6, arm A, and 80 mFOLFOX + aflibercept, arm B). The incidence of all grade adverse events was similar in both arms, however, adverse events grade ≥3 were more than twice as high in the experimental arm due to hypertension. Surgical complications were comparable. Aflibercept did not improve the pCR rate (arm A 26% versus arm B 19%, P = 0.47) and more patients in arm B had node positivity. With a median follow-up of 40.1 months, the 4-year disease-free survival was 83% in arm A and 85% in arm B (P = 0.82). Only two patients in arm A and one patient in arm B developed local recurrence.

CONCLUSIONS

In patients with locally advanced rectal cancer and MRI-defined low risk of local recurrence, neoadjuvant mFOLFOX6 + aflibercept was feasible and did not compromise surgery. Survival data were favorable in both arms, but pCR rates were not increased by the addition of aflibercept.

Neoadjuvant Chemotherapy in Colon Cancer: More Than Just an Optical Illusion

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Neoadjuvant chemotherapy with capecitabine combined with oxaliplatin for mid-low locally advanced rectal cancer with negative mesorectal fascia: Long-term outcomes of a prospective trial (PKUCH-R03 trial)

OBJECTIVE

To evaluate the safety and efficacy of neoadjuvant chemotherapy (NCT) in mid-low locally advanced rectal cancer with negative mesorectal fascia (MRF).

METHODS

This prospective, single-arm phase II trial was designed and conducted at Peking University Cancer Hospital. The patients who provided consent received 3 months of NCT (capecitabine and oxaliplatin, CapOX) followed by total mesorectal excision (TME). The primary endpoint was the rate of pathological complete response (pCR).

RESULTS

From January 2019 through December 2021, a total of 53 patients were enrolled, 7.5% of whom experienced grade 3-4 adverse events during NCT. The pCR rate was 17.0% for the entire cohort, and the overall rate of postoperative complications was 37.7% (1.9% of grade IIIa patients). The 3-year disease-free survival rate was 91.4%, and 23.5% (12/51) of the patients suffered from major low anterior resection syndrome (LARS). Postoperative complications were independently associated with major LARS.

CONCLUSIONS

For patients with mid-low rectal cancer with negative MRF, 3 months of NCT were found to yield a favorable tumor response with acceptable toxicity. With fair long-term survival, the NCT regimen could be associated with low rates of perioperative complications as well as acceptable anal function.

Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer: How to Select the Most Suitable?

Rectal cancer shows specific characteristics in terms of pattern of recurrence, which occurs commonly at both local and distant sites. The standard of care for locally advanced rectal cancer (LARC) including neoadjuvant chemoradiotherapy, followed by surgery based on the total mesorectal excision principles leads to a reduction in the rates of local recurrences to 6-7% at 5 years. However, the outcomes among those with high-risk lesions remain unsatisfactory. On the contrary, neoadjuvant chemoradiotherapy results in long-term morbidities among those with low-risk lesions. Furthermore, the overall survival benefit of neoadjuvant therapy is still a subject to be debated, except for patients with complete or near-complete response to neoadjuvant therapy. Total neoadjuvant therapy (TNT) is a new paradigm of management of high-risk rectal cancer that includes early administration of the most effective systemic therapy either before or after neoadjuvant radiotherapy with or without chemotherapy prior to surgery with or without adjuvant chemotherapy. TNT potentially improves disease-free survival, even though whether it can prolong survival has been debatable. Recently, neoadjuvant chemotherapy only has been proved to be non-inferior to neoadjuvant chemoradiotherapy in patients with low-risk lesions. This review intends to review the current evidences of neoadjuvant therapy and propose a more customized paradigm of management of LARC.

Journey through the Decades: The Evolution in Treatment and Shared Decision Making for Locally Advanced Rectal Cancer

The management of locally advanced rectal cancer has undergone significant transformations over the decades and optimal treatment approaches continue to evolve. There have been numerous advances in surgery, chemotherapy, and radiation therapy from the first description of the abdominoperineal resection in 1908, timing of chemotherapy and radiation therapy in the late 20th and early 21st century, and most recently, the introduction of organ preservation or nonoperative management in 2004. Alongside these advancements, the concept of shared decision making in medicine has evolved, prompting a focus on patient-centered care. This evolution in practice has been fueled by a growing recognition of the importance of patient autonomy and the alignment of treatment options with patients' values and preferences. With the growing number of possible treatment options, variability in patient counseling exists, highlighting the need for a standardized approach to shared decision making in locally advanced rectal cancer. This narrative review will describe the evolution of treatment options of locally advanced rectal cancer as well as the concept of shared decision making and decision aids, and will introduce a decision aid for patients with locally advanced rectal cancer who have achieved a complete clinical response and are eligible for watch and wait.

Significance of MRI-based radiomics in predicting pathological complete response to neoadjuvant chemoradiotherapy of locally advanced rectal cancer: A narrative review

Neoadjuvant chemoradiotherapy is the standard treatment for patients with locally advanced rectal cancers owing to its ability to downstage primary tumours. Some patients can achieve pathological complete response after neoadjuvant therapy, and can adopt a "watch and wait" treatment strategy to avoid overtreatment. Therefore, it is essential to develop strategies for predicting responses to neoadjuvant therapy. Radiomics has shown great potential in extracting tumour features from high-throughput medical images for the construction of mathematics models for predicting the effects of anticancerous therapies. Herein, we explored MRI-based radiomics and found that it can predict responses of locally advanced rectal cancers to chemoradiation. Efficient radiomics model allow early-stage prediction of the effect of neoadjuvant chemoradiotherapy on locally advanced rectal cancers. It helps clinicians to make informed therapeutic decisions. In this review, we discuss the workflow of radiomics, and summarize the clinical application of MRI-based radiomics in predicting pathological complete response to neoadjuvant chemoradiotherapy of locally advanced rectal cancer.

Clinical Analysis of the Efficacy and Safety of Different Neoadjuvant Strategies in the Treatment of Locally Advanced Rectal Cancer

OBJECTIVE

In this study, we retrospectively analysed the efficacy and safety of three treatment models, namely, short-course radiotherapy sequential XELOX chemotherapy, neoadjuvant mFOLFOX6 concurrent radiotherapy and long-course concurrent radiotherapy with total mesorectal excision (TME) after treatment of locally advanced rectal cancer with high-risk factors.

METHODS

We collected clinical data on 177 patients with locally advanced rectal cancer (cT3-4 and/or cN+) who were treated at the Department of Abdominal Oncology of the Affiliated Cancer Hospital of Guizhou Medical University from December 2017 to December 2022. All patients were associated with 2-3 risk factors [T4b, N2, Extramural Vascular Invasion (EMVI), Mesorectal Fascia (MRF) positivity], positive lateral lymph nodes. Among them, there were 45 cases in the short course radiotherapy sequential XELOX chemotherapy group (RT + XELOX group); 64 cases in the neoadjuvant mFOLFOX6 concurrent radiotherapy group (mFOLFOX6 + CRT group); and 68 cases in the long course concurrent radiotherapy group (CRT group). The RT + XELOX group and mFOLFOX6 + CRT group completed radiotherapy and 4 cycles of neoadjuvant chemotherapy, respectively, and then rested for 1-2 weeks before TME surgery; the CRT group completed concurrent radiotherapy and then rested for 6-8 weeks before TME surgery.Adjuvant chemotherapy was conducted after surgery in each of the three groups: 2 cycles of adjuvant chemotherapy with XELOX regimen in the RT + XELOX group, 4-6 cycles of adjuvant chemotherapy with mFOLFOX6 in the mFOLFOX6 + CRT group, and 8-12 cycles of adjuvant chemotherapy with mFOLFOX6 in the CRT group.The pathological complete response rate (pCR rate), tumour downstage rate, tumour complete resection rate (R0 resection rate), local recurrence rate, distant metastasis rate, overall survival rate, incidence of adverse reactions, surgical complications and completion rate of perioperative systemic chemotherapy were compared among patients in the three groups of cases after TME.

RESULTS

The pCR rate (21.95% vs 17.24% vs 5.00%, p = 0.034) and and tumour downstage rate (78.05% vs 68.97% vs 53.33%, p = 0.029) were higher in the RT + XELOX group and mFOLFOX6 + CRT group compared to the CRT group. The RT + XELOX group had a lower 3-year distant metastasis rate (14.63% vs 36.67%, p = 0.048) and improved 3-year overall survival (76.57% vs 48.56%, p < 0.001) compared to the CRT group. There was no significant reduction in the 3-year distant metastasis rate in the mFOLFOX6 + CRT group versus the CRT group (27.59% vs 36.67%, p = 0.719), and the 3-year overall survival was similar (51.23% vs 48.56%, p = 0.35). Multi-logistic regression analysis and stratified analysis showed that patients in the RT + XELOX group and mFOLFOX6 + CRT group were more likely to achieve pCR than the CRT group (RT + XELOX group: OR 7.3, 95% CI [2.6-20.8], p < 0.001; mFOLFOX6 + CRT group OR 2.9, 95% CI [1.1-7.9], p = 0.036). The completion rates of perioperative systemic chemotherapy in the RT + XELOX, mFOLFOX6 + CRT, and CRT groups were 82.93% vs. 84.48% vs. 61.67% (χ2=9.95, p = 0.007), respectively. And there were significant differences in grade 3-4 leukopenia and thrombocytopenia (incidence of leukopenia: 15.50% vs. 7.81% vs. 1.47%, p = 0.045; incidence of thrombocytopenia: 13.33% vs 7.81% vs 1.47%, p = 0.027). There was no significant difference in the incidence of intraoperative and postoperative complications among the three groups (p > 0.05).

CONCLUSIONS

RT + XELOX group and mFOLFOX6 + CRT group significantly improved the near-term outcome (e.g., pCR rate) in patients with locally advanced rectal cancer with high-risk factors compared with CRT group. The RT + XELOX group also reduced the 3-year distant metastasis rate, increased the 3-year overall survival rate, and did not increase the incidence of perioperative surgical complications. It provides an effective means for the comprehensive treatment of locally advanced rectal cancer and has important clinical guidance and application value.