Oxaliplatin, fluorouracil, and leucovorin with or without cetuximab in patients with resected stage III colon cancer (PETACC-8): an open-label, randomised phase 3 trial

Prognostic Models From Transcriptomic Signatures of the Tumor Microenvironment and Cell Cycle in Stage III Colon Cancer From PETACC-8 and IDEA-France Trials

PURPOSE

The objective of this work was to establish prognostic models in stage III colon cancer (CC) on the basis of transcriptomic signatures of the tumor microenvironment (TME) and cell cycle from the PETACC-8 (training set) and IDEA-France (validation set) trials.

PATIENTS AND METHODS

3'RNA sequencing was performed in 1,733 patients from the PETACC-8 trial and 1,248 patients from the IDEA-France trial. Four transcriptomic signatures were analyzed: T-cell and macrophage M2 signatures, the expression of CXCL13, and a score on the basis of the Oncotype DX CC Recurrence Score using the same formula from the stromal score and the cell cycle score. The Immune Proliferative Stromal (IPS) score was defined as the number of dichotomized signatures that fall under the category of a dismal prognosis (from 0 to 4). Time to recurrence (TTR) was defined as the time from the date of random assignment to local and/or metastatic relapse and/or death because of CC, whichever occurs first.

RESULTS

High Oncotype-like and M2 scores and low CXCL13 expression and T-cell score were associated with a shorter TTR. A multivariable model including these signatures and all known prognostic factors applied to the IDEA-France cohort by obtaining a value of this model for each patient showed TTR significantly different depending on the quartile of this value and a 3-year rate of patients without recurrence ranging from 56% for the lowest quartile to 89% for the highest quartile (P < .0001). The IPS score was significantly associated with TTR in multivariable analysis.

CONCLUSION

Using transcriptomic data of patients with stage III CC from two large-scale adjuvant trials, a prognostic model on the basis of signatures of the TME and the cell cycle provides important information in addition to known prognostic factors for patient stratification on risk of recurrence.

Aspirin after completion of standard adjuvant therapy for colorectal cancer (ASCOLT): an international, multicentre, phase 3, randomised, double-blind, placebo-controlled trial

BACKGROUND

Aspirin is a simple, globally available medication that has been shown to reduce the incidence of colorectal cancer. We aimed to evaluate the safety and efficacy of aspirin in the secondary prevention of colorectal cancer.

METHODS

This phase 3, randomised, double-blind, placebo-controlled trial was conducted at 66 centres across 11 countries and territories (ten in Asia-Pacific; one in the Middle East). The trial included patients aged 18 years and older with Dukes' C or high-risk Dukes' B colon cancer or Dukes' B or C rectal cancer who had undergone resection and had completed standard adjuvant therapy (at least 3 months of chemotherapy). Patients with contraindications to aspirin, familial syndromes of colorectal cancer, recent other cancers, and clinically significant history of cardiovascular disease or stroke were excluded. Patients were randomly assigned (1:1) to aspirin 200 mg daily or placebo for 3 years, and were followed up for 5 years. Randomisation was stratified by study centre, tumour site and stage, and inclusion of oxaliplatin in adjuvant chemotherapy. The patients, study team, and sponsor were masked to treatment assignment. The primary endpoint was disease-free survival. The primary analysis used a stratified Cox model in those commencing study treatment (modified intention-to-treat population), analysing all events to March 31, 2023. Safety was analysed in the same population. This trial is registered at ClinicalTrials.gov (NCT00565708). The primary analysis has been completed, but translational studies of putative aspirin sensitivity biomarkers are ongoing.

FINDINGS

Between Feb 25, 2009, and June 30, 2021, 1587 patients underwent randomisation, of whom 1550 were included in the modified intention-to-treat analysis: 791 (51%) in the aspirin group and 759 (49%) in the placebo group. Of these patients, the median age was 57 years (IQR 48-65); 897 (58%) were male and 653 (42%) female; 271 (17%) had Dukes' B colon cancer, 770 (50%) Dukes' C colon cancer, and 509 (33%) rectal cancer. Median follow-up at data cutoff was 59·2 months (IQR 36·7-60·0). 5-year disease-free survival was 77·0% (95% CI 73·6-80·0) in the aspirin group and 74·8% (71·3-77·9) in the placebo group (hazard ratio of 0·91 [95% CI 0·73-1·13]; p=0·38). Any-grade adverse events were reported in 390 (49%) of 791 patients in the aspirin group versus 386 (51%) of 759 in the placebo group. Serious adverse events were reported in 95 (12%) patients in the aspirin group versus 107 (14%) in the placebo group. There were no treatment-related deaths in either group. Among adverse events of special interest, there were no cases of acute myocardial infarction in the aspirin group versus two in the placebo group; no ischaemic cerebrovascular events in the aspirin group versus two in the placebo group; and three major gastrointestinal bleeds in the aspirin group versus one in the placebo group.

INTERPRETATION

In patients with colorectal cancer, aspirin 200 mg daily for 3 years after completion of standard adjuvant therapy was well tolerated but did not significantly improve disease-free survival.

FUNDING

SingHealth Foundation, National Medical Research Council Singapore, National Cancer Centre Research Fund, Rising Tide Foundation, Lee Foundation, Lee Kim Tah Foundation, Duke-NUS Khoo Bridge Funding Award, Terry-Fox Run, Silent Foundation, Cancer Australia, Bowel Cancer Australia, and Cancer Council NSW.

Neo-adjuvant FOLFOX with and without panitumumab for patients with KRAS-wt locally advanced colon cancer: results following an extended biomarker panel on the FOxTROT Trial embedded phase II population

BACKGROUND

The FOxTROT trial has reported advantages of neoadjuvant chemotherapy (NAC) in locally advanced colon cancer (LACC). Here we present results of the embedded randomized phase II trial testing the addition of panitumumab to neoadjuvant FOLFOX compared with FOLFOX alone in RAS and BRAF-wild-type patients and with biomarker hyperselction.

PATIENTS AND METHODS

Patients had operable, CT-predicted stage T3-4, N0-2, M0 colon adenocarcinoma. KRAS-wt pts allocated to NAC could optionally be sub-randomized 1:1 to FOLFOX ± panitumumab during the pre-operative phase. RAS/BRAF were tested by NGS; EREG/AREG by RNAseq. Primary endpoint is time to recurrence (TTR) in RAS/BRAF-wt patients; secondary endpoints include safety, histological downstaging, disease-free survival (DFS), colon cancer-specific survival (CCSS), overall survival (OS), and impact of primary tumor location and EREG/AREG.

RESULTS

In total 269 KRAS-wt patients were enrolled into the embedded phase II trial. Extended RAS/BRAF data were available for 232 (83%) patients; 22/232(9.5%) were RAS-mutant; 41/210(20%) were BRAF-mutant. Median follow up was 42 months. In 169 RAS/BRAF-wt patients there was a trend towards reduced recurrences with FOLFOX plus panitumumab compared with FOLFOX (12% vs 21%, HR=0.51, p=0.09); significant improvements were seen for DFS, CCSS and OS. Within the hyperselected EREG/AREG high group, there was significant reduction in recurrences with panitumumab. Panitumumab was not associated with increased pathological regression of the primary tumor (TRG 1-3 16% vs 22%,p=0.27). FOLFOX plus panitumumab was associated with higher rates of grade 3 diarrhoea (8% vs 3%,) and rash (22% vs 2%).

CONCLUSION

This exploratory analysis from a randomized phase II study shows a non-significant improvement in TTR from the addition of neoadjuvant panitumumab to peri-operative FOLFOX in RAS/BRAF-wt LACC. Hyperselection with EREG/AREG status was associated with increased efficacy. A dedicated prospective trial within a biomarker selected population is under development.

CLINICAL TRIALS REGISTRATION

ISRCTN87163246.

Neoadjuvant chemotherapy in locally advanced colon cancer: A systematic review with proportional meta-analysis

Neoadjuvant chemotherapy is suggested in locally advanced colon cancer. Data on improved long-term oncological outcomes are lacking, which hampers the implementation in clinical practice. This systematic review provides an overview of the benefits and drawbacks of neoadjuvant chemotherapy in patients with locally advanced colon cancer. A systematic literature search was performed using Embase (OVID), MEDLINE (OvidSP), and the Cochrane Library. Studies reporting on the efficacy of neoadjuvant chemotherapy in patients with operable, locally advanced colon cancer without metastases at the time of diagnosis were considered eligible for inclusion. An overview of short- and long-term outcomes of neoadjuvant chemotherapy is provided based on available literature. Additionally, proportional meta-analyses were performed using MedCalc Statistical Software version 19.2.6. A total of 17 unique studies were included in this review, 3 randomised controlled trials and 14 prospective single-arm or retrospective studies. The maximum reported dropout before surgery was 7.8 % in the neoadjuvant chemotherapy group. A histopathological complete response after neoadjuvant chemotherapy was observed in 0-4.8 % of the patients. The occurrence of anastomotic leaks was less than 8 % for both patients treated with neoadjuvant chemotherapy and patients treated with upfront surgery. Neoadjuvant chemotherapy is a safe alternative for adjuvant chemotherapy based on the dropout rate before surgery and the peri-operative morbidity and peri-operative mortality. Robust long-term survival outcomes are lacking and serious concerns regarding the risk of overtreatment have been expressed. Hence, neoadjuvant chemotherapy might be considered in a select group of patients with locally advanced colon cancer.

A novel risk classification model integrating CEA, ctDNA, and pTN stage for stage 3 colon cancer: a post hoc analysis of the IDEA-France trial

BACKGROUND

We assessed the added value of incorporating carcinoembryonic antigen (CEA) to circulating tumor DNA (ctDNA) and pathological TN (pTN) stage for risk classification in stage 3 colon cancer (CC).

PATIENTS AND METHODS

We retrospectively analyzed postoperative CEA values in patients with CC from the IDEA-France phase 3 trial. The relation between disease-free survival (DFS) and CEA was modeled through restricted cubic splines. Prognostic value of CEA, ctDNA, and pTN was assessed with the Kaplan-Meier method. Multivariate analysis was used to identify prognostic and predictive factors for DFS.

RESULTS

Among 696 patients (35%), CEA values were retrievable, and for 405 (20%) both CEA and ctDNA were available. An optimized CEA threshold of 2 ng/mL was identified, the 3-year DFS was 66.4% for patients above the threshold and 80.9% for those below (HR, 1.74; 95% CI, 1.33-2.28, P < .001). In multivariate analysis, CEA ≥ 2 ng/mL contributed significantly to model variability, becoming an independent prognostic factor for DFS (HR, 1.82; 95% CI,1.27-2.59), alongside ctDNA (HR, 1.88; 95% CI, 1.16-3.03) and pTN (HR, 1.78; 95% CI, 1.24-2.54). A novel integrated risk classification combining CEA, ctDNA, and pTN stage reclassified 19.8% of pT4/N2 patients as low risk and 2.5% of pT3/N1 patients as high risk. This new classification demonstrated the 3-year DFS of 80.8% for low-risk patients and 55.4% for high-risk patients (HR, 2.66, 95% CI, 1.84-3.86, P < .001).

CONCLUSIONS

Postoperative CEA value is a prognostic factor for DFS in stage 3 CC, independently of ctDNA and pTN. It advocates for systematic reporting in future adjuvant trials. Integrating both biomarkers with pTN could refine risk classification in stage 3 CC.

Oxaliplatin-induced peripheral neuropathy with hepatic arterial versus intravenous infusion in metastatic colorectal cancer

BACKGROUND

Oxaliplatin, a major drug in metastatic colorectal cancer (mCRC), is responsible for cumulative, dose-limiting peripheral neuropathy (PN). Whether the hepatic arterial infusion (HAI) route can limit oxaliplatin-induced PN in comparison with the intravenous (IV) route has not been specifically explored so far.

METHODS

We compared the frequency and severity of PN in oxaliplatin-naive patients with mCRC included in trials that evaluated treatment with oxaliplatin administered either by HAI (ACCORD 04, CHOICE, OSCAR, and PACHA-01 trials) or by IV route (FFCD 2000-05 trial). We retrieved anonymized, prospectively collected data from trial databases for the ACCORD 04, CHOICE, and FFCD 2000-05 trials and through a review of Gustave Roussy patients' electronic medical records for PACHA-01 and OSCAR trials. The primary endpoint was the incidence of clinically significant PN (grades 2 to 4) according to the cumulative dose of oxaliplatin received. Secondary endpoints were time to onset of neuropathy as a function of the cumulative dose of oxaliplatin, discontinuation of oxaliplatin for neurotoxicity, and safety.

RESULTS

A total of 363 patients were included (IV, 300; HAI, 63). In total, 180 patients in the IV group (60%) and 30 patients in the HAI group (48%) developed clinically significant PN, with no significant difference between the two groups (p = 0.23). No difference was shown in the time to onset of PN either (p = 0.23).

CONCLUSION

The administration of oxaliplatin HAI rather than IV in the treatment of mCRC does not reduce the incidence, precocity, and severity of PN.

A log odds of positive lymph nodes-based predictive model effectively forecasts prognosis and guides postoperative adjuvant chemotherapy duration in stage III colon cancer: a multi-center retrospective cohort study

BACKGROUND

The log odds of positive lymph nodes (LODDS) was considered a superior staging system to N stage in colon cancer, yet its value in determining the optimal duration of adjuvant chemotherapy for stage III colon cancer patients has not been evaluated. This study aims to assess the prognostic value of a model that combines LODDS with clinicopathological information for stage III colon cancer patients and aims to stratify these patients using the model, identifying individuals who could benefit from varying durations of adjuvant chemotherapy.

METHOD

A total of 663 consecutive patients diagnosed with stage III colon cancer, who underwent colon tumor resection between November 2007 and June 2020 at Sun Yat-sen University Cancer Center and Longyan First Affiliated Hospital of Fujian Medical University, were enrolled in this study. Survival outcomes were analyzed using Kaplan-Meier, Cox regression. Nomograms were developed to forecast patient DFS, with the Area Under the Curve (AUC) values of time-dependent Receiver Operating Characteristic (timeROC) and calibration plots utilized to assess the accuracy and reliability of the nomograms.

RESULTS

Multivariate analysis revealed that perineural invasion (HR = 1.776, 95% CI: 1.052-3.003, P = 0.032), poor tumor differentiation (HR = 1.638, 95% CI: 1.084-2.475, P = 0.019), and LODDS groupings of 2 and 1 (HR = 1.920, 95% CI: 1.297-2.842, P = 0.001) were independent predictors of disease-free survival (DFS) in the training cohort. Nomograms constructed from LODDS, perineural invasion, and poor tumor differentiation demonstrated robust predictive performance for 3-year and 5-year DFS in both training (3-year AUC = 0.706, 5-year AUC = 0.678) and validation cohorts (3-year AUC = 0.744, 5-year AUC = 0.762). Stratification according to this model showed that patients in the high-risk group derived significant benefit from completing 8 cycles of chemotherapy (training cohort, 82.97% vs 67.17%, P = 0.013; validation cohort, 89.49% vs 63.97%, P = 0.030).

CONCLUSION

The prognostic model, integrating LODDS, pathological differentiation, and neural invasion, demonstrates strong predictive accuracy for stage III colon cancer prognosis. Moreover, stratification via this model offers valuable insights into optimal durations of postoperative adjuvant chemotherapy.

PIPAC in patients with peritoneal metastases from gastrointestinal tract (PIPOX01): An open label, non-comparative phase 1/2 dose escalation and expansion trial

BACKGROUND

Despite modern systemic chemotherapy, survival remains poor for patients with advanced isolated peritoneal metastases from the gastrointestinal tract. We aimed to assess the safety and efficacy of pressurized intraperitoneal aerosol chemotherapy (PIPAC) with oxaliplatin.

PATIENTS AND METHODS

We conducted a phase 1/2, open label, non-comparative, dose escalation and expansion trial of PIPAC with oxaliplatin in patients with a peritoneal cancer index (PCI) of more than 5, 13 and 15 for respectively a gastric, small bowel and colorectal primary cancer, and who had received at least three months of systemic chemotherapy. PIPAC cycle lengths were 4-6 weeks with systemic chemotherapy allowed 15 days after each PIPAC. PCI and oxaliplatin tumor concentration were assessed every PIPAC cycle. The main endpoints were tolerability, tumor response, and survival.

RESULTS

Between 2017 and 2020, 34 patients were enrolled in three centers, in this phase 1/2 study, of whom 25 were evaluable at the recommended dose determined in the phase I trial (90 mg/m2 plus systemic 5-FU). Before inclusion, patients received a median of 2 [1-4] chemotherapy lines and had a median PCI of 22.5 [7-29]. At this dose, the safety profile showed acceptable tolerability. Eight patients (32 %) had grade 3/4 treatment-related adverse events. Minor (grade 1/2) adverse events were mainly abdominal pain (n = 19, 76 %) and nausea (n = 16, 64 %). Median PFS was 6.1 months and median OS was 13 months.

CONCLUSION

In patients with advanced and refractory peritoneal metastasis, PFS of 6.1 months is encouraging. A prospective randomized phase II study is required.

Neoadjuvant Chemotherapy With Oxaliplatin and Fluoropyrimidine Versus Upfront Surgery for Locally Advanced Colon Cancer: The Randomized, Phase III OPTICAL Trial

PURPOSE

The role of neoadjuvant chemotherapy (NAC) in colon cancer remains unclear. This trial investigated whether 3 months of modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) or capecitabine and oxaliplatin (CAPOX) as NAC could improve outcomes in patients with locally advanced colon cancer versus upfront surgery.

PATIENTS AND METHODS

OPTICAL was a randomized, phase III trial in patients with clinically staged locally advanced colon cancer (T3 with extramural spread into the mesocolic fat ≥5 mm or T4). Patients were randomly assigned 1:1 to receive six preoperative cycles of mFOLFOX6 or four cycles of CAPOX, followed by surgery and adjuvant chemotherapy (NAC group), or immediate surgery and the physician's choice of adjuvant chemotherapy (upfront surgery group). The primary end point was 3-year disease-free survival (DFS) assessed in the modified intention-to-treat (mITT) population.

RESULTS

Between January 2016 and April 2021, of the 752 patients enrolled, 744 patients were included in the mITT analysis (371 in the NAC group; 373 in the upfront surgery group). At a median follow-up of 48.0 months (IQR, 46.0-50.1), 3-year DFS rates were 82.1% in the NAC group and 77.5% in the upfront surgery group (stratified hazard ratio [HR], 0.74 [95% CI, 0.54 to 1.03]). The R0 resection was achieved in 98% of patients who underwent surgery in both groups. Compared with upfront surgery, NAC resulted in a 7% pathologic complete response rate (pCR), significantly lower rates of advanced tumor staging (pT3-4: 77% v 94%), lymph node metastasis (pN1-2: 31% v 46%), and potentially improved overall survival (stratified HR, 0.44 [95% CI, 0.25 to 0.77]).

CONCLUSION

NAC with mFOLFOX6 or CAPOX did not show a significant DFS benefit. However, this neoadjuvant approach was safe, resulted in substantial pathologic downstaging, and appears to be a viable therapeutic option for locally advanced colon cancer.

Curative Surgery After Neoadjuvant Chemotherapy for Locally Advanced Sigmoid Colon Cancer With Extensive Abdominal Wall Invasion: A Case Report

Locally advanced colon cancer (LACC) can be cured under an appropriate treatment strategy, but the decision on the treatment strategy is also important in terms of long-term prognosis. In cases with extensive abdominal wall involvement, it is especially important to secure adequate margins and repair abdominal wall defects. Recently, neoadjuvant chemotherapy (NAC) for LACC has shown promise in improving the chance of cure with tumor shrinkage. Herein, we report a case of curative surgery after NAC for locally advanced sigmoid colon cancer with extensive abdominal wall invasion. A 50-year-old woman visited our hospital with anemia and an abdominal mass. The diagnosis was LACC of the sigmoid colon with abdominal wall invasion (maximum size, 12 cm), and the clinical stage was stage IIIc (T4b[skin]N1bM0). Resection of the involved skin was expected to cause an extensive abdominal wall defect. At first, a colostomy was performed, followed by NAC with leucovorin, 5-fluorouracil, and oxaliplatin (FOLFOX). Ten cycles of chemotherapy were completed without severe adverse events, and the tumor shrank in size by approximately 39%. We performed a curative sigmoidectomy combined with abdominal wall resection with adequate margins. We reconstructed the abdominal wall defect using a left anterolateral thigh skin flap. Pathological examination revealed mucinous carcinoma involving the transverse colon and abdominal wall, with luminal narrowing in the sigmoid colon. The surgical margins were negative, and the tumor was considered to have had a pathological partial response to NAC. Herein, we report a rare case of curative surgery after NAC with FOLFOX for LACC in the sigmoid colon with extensive invasion of the abdominal wall. We reconstructed the extensive abdominal wall defect with a free anterolateral thigh flap. One of the optional treatment strategies for LACC with extensive abdominal wall invasion was reported in our report.

Machine learning evaluation of immune infiltrate through digital tumour score allows prediction of survival outcome in a pooled analysis of three international stage III colon cancer cohorts

BACKGROUND

T-cell immune infiltrates are robust prognostic variables in localised colon cancer. Evaluation of prognosis using artificial intelligence is an emerging field. We evaluated whether machine learning analysis improved prediction of patient outcome in comparison with analysis of T cell infiltrate only or in association with clinical variables.

METHODS

We used data from two phase III clinical trials (Prodige-13 and PETACC08) and one retrospective Italian cohort (HARMONY). Cohorts were split into training (N = 692), internal validation (N = 297) and external validation (N = 672) sets. Tumour slides were stained with CD3mAb. CD3 Machine Learning (CD3ML) score was computed using graphical parameters within the tumour tiles obtained from CD3 slides. CD3 infiltrates in tumour core and invasive margin were automatically detected. Associations of CD3 infiltrates and CD3ML with 5-year Disease-Free Survival (DFS) were examined using univariate and multivariable survival models by Cox regression.

FINDINGS

CD3 density both in the invasive margin and the tumour core were significantly associated with DFS in the different sets. Similarly, CD3ML score was significantly associated with DFS in all sets. CD3 assessment did not provide added value on top of CD3ML assessment (Likelihood Ratio Test (LRT), p = 0.13). In contrast, CD3ML improved prediction of DFS when combined with a clinical risk stage (LRT, p = 0.001). Stratified by clinical risk score (High or Low), patients with low CD3ML score had better DFS.

INTERPRETATION

In all tested sets, machine learning analysis of tumour cells improved prediction of prognosis compared to clinical parameters. Adding tumour-infiltrating lymphocytes assessment did not improve prognostic determination.

FUNDING

This research received no external funding.

Oxaliplatin-Based Adjuvant Chemotherapy in Older Patients With Stage III Colon Cancer: An ACCENT/IDEA Pooled Analysis of 12 Trials

PURPOSE

A number of studies suggest that older patients may have reduced or no benefit from the addition of oxaliplatin to fluoropyrimidines as adjuvant chemotherapy for stage III colon cancer (CC).

MATERIALS AND METHODS

We studied the prognostic impact of age, as well as treatment adherence/toxicity patterns according to age, in patients with stage III CC who received 3 or 6 months of infusional fluorouracil, leucovorin, and oxaliplatin/capecitabine and oxaliplatin (CAPOX) on the basis of data collected from trials from the ACCENT and IDEA databases. Associations between age and time to recurrence (TTR), disease-free survival (DFS), overall survival (OS), survival after recurrence (SAR), and cancer-specific survival (CSS) were assessed by a Cox model or a competing risk model, stratified by studies and adjusted for sex, performance status, T and N stage, and year of enrollment.

RESULTS

A total of 17,909 patients were included; 24% of patients were age older than 70 years (n = 4,340). Patients age ≥70 years had higher rates of early treatment discontinuation. Rates of grade ≥3 adverse events were similar between those older and younger than 70 years, except for diarrhea and neutropenia that were more frequent in older patients treated with CAPOX (14.2% v 11.2%; P = .01 and 12.1% v 9.6%; P = .04, respectively). In multivariable analysis, TTR was not significantly different between patients <70 years and those ≥70 years, but DFS, OS, SAR, and CSS were significantly shorter in those patients ≥70 years.

CONCLUSION

In patients ≥70 years with stage III CC fit enough to be enrolled in clinical trials, oxaliplatin-based adjuvant chemotherapy was well tolerated and led to similar TTR compared with younger patients, suggesting similar efficacy. TTR may be a more appropriate end point for efficacy in this patient population.

Resistant Starch-Encapsulated Probiotics Attenuate Colorectal Cancer Cachexia and 5-Fluorouracil-Induced Microbial Dysbiosis

5-Fluorouracil (5-FU) is commonly used as the primary chemotherapy for colorectal cancer (CRC). However, it can lead to unwanted chemoresistance. Resistant starch (RS), which functions similarly to fermentable dietary fiber, has the potential to reduce the risk of CRC. The effects of RS on improving CRC-associated cachectic symptoms and 5-FU chemotherapy-induced microbial dysbiosis remain unknown. Female BALB/cByJNarl mice were randomly divided into four groups: one tumor group (with CT26 colonic carcinoma but no treatment) and three CT26 colonic carcinoma-bearing groups that were administered 20 mg/kg 5-FU (T+5-FU group), a probiotic cocktail (4 × 108 CFUs) plus chemotherapy (T+5-FU+Pro), or resistant-starch-encapsulated probiotics plus chemotherapy (T+5-FU+RS-Pro). T+5-FU and T+5-FU+RS-Pro administration significantly suppressed tumor growth and activated apoptotic cell death in CT26-bearing mice. 5-FU-induced increases in inflammatory cytokines and NF-κB signaling were mitigated by the Pro or RS-Pro supplementation. A gut microbial composition comparison indicated that the abundance of intestinal bacteria in the T and T+5-FU groups decreased significantly, while the groups receiving Pro or RS-Pro maintained a greater abundance and healthy gut microbiota composition, suggesting that RS can reduce the microbial dysbiosis that occurs during 5-FU chemotherapy. The use of RS-Pro before chemotherapy should be considered for the regulation of chemotherapy-associated cachectic symptoms, inflammation, and chemotherapy-induced microbial dysbiosis.

The crosstalk between non-coding RNAs and cell-cycle events: A new frontier in cancer therapy

The cell cycle comprises sequential events during which a cell duplicates its genome and divides it into two daughter cells. This process is tightly regulated to ensure that the daughter cell receives identical copied chromosomal DNA and that any errors in the DNA during replication are correctly repaired. Cyclins and their enzyme partners, cyclin-dependent kinases (CDKs), are critical regulators of G- to M-phase transitions during the cell cycle. Mitogenic signals induce the formation of the cyclin/CDK complexes, resulting in phosphorylation and activation of the CDKs. Once activated, cyclin/CDK complexes phosphorylate specific substrates that drive the cell cycle forward. The sequential activation and inactivation of cyclin-CDK complexes are tightly controlled by activating and inactivating phosphorylation events induced by cell-cycle proteins. The non-coding RNAs (ncRNAs), which do not code for proteins, regulate cell-cycle proteins at the transcriptional and translational levels, thereby controlling their expression at different cell-cycle phases. Deregulation of ncRNAs can cause abnormal expression patterns of cell-cycle-regulating proteins, resulting in abnormalities in cell-cycle regulation and cancer development. This review explores how ncRNA dysregulation can disrupt cell division balance and discusses potential therapeutic approaches targeting these ncRNAs to control cell-cycle events in cancer treatment.

Non-metastatic colon cancer: French Intergroup Clinical Practice Guidelines for diagnosis, treatments, and follow-up (TNCD, SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, ACHBT, SFP, AFEF, and SFR)

INTRODUCTION

This article is a summary of the French intergroup guidelines regarding the management of non-metastatic colon cancer (CC), revised in November 2022.

METHODS

These guidelines represent collaborative work of all French medical and surgical societies involved in the management of CC. Recommendations were graded in three categories (A, B, and C) according to the level of evidence found in the literature published up to November 2022.

RESULTS

Initial evaluation of CC is based on clinical examination, colonoscopy, chest-abdomen-pelvis computed tomography (CT) scan, and carcinoembryonic antigen (CEA) assay. CC is usually managed by surgery and adjuvant treatment depending on the pathological findings. The use of adjuvant therapy remains a challenging question in stage II disease. For high-risk stage II CC, adjuvant chemotherapy must be discussed and fluoropyrimidine monotherapy or oxaliplatin-based chemotherapy proposed according to the type and number of poor prognostic features. Oxaliplatin-based chemotherapy (FOLFOX or CAPOX) is the current standard for adjuvant therapy of patients with stage III CC. However, these regimens are associated with significant oxaliplatin-induced neurotoxicity. The results of the recent IDEA study provide evidence that 3 months of treatment with CAPOX is as effective as 6 months of oxaliplatin-based therapy in patients with low-risk stage III CC (T1-3 and N1). A 6-month oxaliplatin-based therapy remains the standard of care for high-risk stage III CC (T4 and/or N2). For patients unfit for oxaliplatin, fluoropyrimidine monotherapy is recommended.

CONCLUSION

French guidelines for non-metastatic CC management help to offer the best personalized therapeutic strategy in daily clinical practice. Each individual case must be discussed within a multidisciplinary tumor board and then the treatment option decided with the patient.

mFOLFIRINOX versus mFOLFOX 6 as adjuvant treatment for high-risk stage III colon cancer - the FROST trial: study protocol for a multicenter, randomized controlled, phase II trial

BACKGROUND

High-risk stage III colon cancer has a considerably poorer prognosis than stage II and low-risk stage III colon cancers. Nevertheless, most guidelines recommend similar adjuvant treatment approaches for all these stages despite the dearth of research focusing on high-risk stage III colon cancer and the potential for improved prognosis with intensive adjuvant treatment. Given the the proven efficacy of triplet chemotherapy in metastatic colorectal cancer treatment, the goal of this study is to evaluate the oncologic efficacy and safety of mFOLFIRINOX in comparison to those of the current standard of care, mFOLFOX 6, as an adjuvant treatment for patients diagnosed with high-risk stage III colon cancer after radical resection.

METHODS

This multicenter, randomized (1:1), open-label, phase II trial will assess and compare the effectiveness and toxicity of mFOLFIRINOX and mFOLFOX 6 in patients with high-risk stage III colon cancer after radical resection. The goal of the trial is to enroll 312 eligible patients, from 11 institutes, aged between 20 and 70 years, with an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, or between 70 and 75 with an ECOG performance status of 0. Patients will be randomized into two arms - Arm A, the experimental arm, and Arm B, the reference arm - and will receive 12 cycles of mFOLFIRINOX and mFOLFOX 6 every 2 weeks, respectively. The primary endpoint of this study is the 3-year disease-free survival, and secondary endpoints include the 3-year overall survival and treatment toxicity.

DISCUSSION

The Frost trial would help determine the oncologic efficacy and safety of adjuvant triplet chemotherapy for high-risk stage III colon cancers and ultimately improve prognoses.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05179889, registered on 17 December 2021.

Prognostic Impact of Primary Tumor Sidedness in Stage III Colorectal Cancer: Real-World Evidence from a Brazilian Cohort

BACKGROUND

Primary tumor sidedness (PTS) is an independent prognostic factor in patients with metastatic colorectal cancer (CRC), with a worse prognosis for right-sided tumors. There are limited data on the prognostic impact of PTS in stage III CRC. The main objective of this study was to analyze the prognostic impact of PTS in stage III CRC.

PATIENTS AND METHODS

A retrospective and uni-institutional cohort study was performed in an oncology reference center. Patients with stage III CRC treated with a 5-fluorouracil and oxaliplatin-based chemotherapy regimen (mFLOX regimen) from October 2007 to February 2013 were included. The primary outcome was the probability of overall survival (OS) at 5 years stratified by PTS. Secondary outcomes were the probability of disease-free survival (DFS) at 5 years and an analysis of the prognostic impact of clinical and molecular biomarkers. Kaplan‒Meier curves were used, and Cox models were used to evaluate prognostic factors associated with OS and DFS.

RESULTS

Overall, 265 patients were evaluated. Transverse colon tumors, multicentric tumors, and undetermined primary subsites were excluded, resulting in 234 patients classified according to PTS: 95 with right sidedness (40.6%) and 139 with left sidedness (59.4%). The median follow-up time was 66 months [interquartile range (IQR): 39-81]. The 5-year OS probabilities for right-sided and left-sided tumors were 67% (95% CI: 58%-77%) and 82% (75%-89%), respectively [hazard ratio (HR): 2.02, 95% CI: 1.18-3.46; P = .010]. The 5-year probabilities of DFS for right-sided and left-sided tumors were 58% (49%-69%) and 65% (58%-74%), respectively (HR: 1.29, 0.84-1.97; P = 0.248).

CONCLUSION

These data suggest that there may be a worse prognosis (inferior OS at 5 years) for resected right-sided stage III CRC patients treated in the real world. However, these data need to be confirmed by prospective studies with a larger number of participants.

Pharmacological modulation of RB1 activity mitigates resistance to neoadjuvant chemotherapy in locally advanced rectal cancer

Resistance to neoadjuvant chemotherapy leads to poor prognosis of locally advanced rectal cancer (LARC), representing an unmet clinical need that demands further exploration of therapeutic strategies to improve clinical outcomes. Here, we identified a noncanonical role of RB1 for modulating chromatin activity that contributes to oxaliplatin resistance in colorectal cancer (CRC). We demonstrate that oxaliplatin induces RB1 phosphorylation, which is associated with the resistance to neoadjuvant oxaliplatin-based chemotherapy in LARC. Inhibition of RB1 phosphorylation by CDK4/6 inhibitor results in vulnerability to oxaliplatin in both intrinsic and acquired chemoresistant CRC. Mechanistically, we show that RB1 modulates chromatin activity through the TEAD4/HDAC1 complex to epigenetically suppress the expression of DNA repair genes. Antagonizing RB1 phosphorylation through CDK4/6 inhibition enforces RB1/TEAD4/HDAC1 repressor activity, leading to DNA repair defects, thus sensitizing oxaliplatin treatment in LARC. Our study identifies a RB1 function in regulating chromatin activity through TEAD4/HDAC1. It also provides the combination of CDK4/6 inhibitor with oxaliplatin as a potential synthetic lethality strategy to mitigate oxaliplatin resistance in LARC, whereby phosphorylated RB1/TEAD4 can serve as potential biomarkers to guide the patient stratification.

Neoadjuvant chemotherapy for early-stage colon cancer

Surgery with or without adjuvant chemotherapy is the standard treatment for early-stage colon cancer. However, evidence has recently emerged for neoadjuvant chemotherapy, with the results of randomised clinical trials sparking debates within multidisciplinary teams and splitting the gastrointestinal oncology community. Further to a systematic search of the literature, we provide a thorough and in-depth analysis of the findings from these trials, highlighting the advantages and disadvantages of neoadjuvant chemotherapy. We conclude that, while there is a potential value of moving systemic therapy from the post-operative to the pre-operative setting, the available evidence does not justify a shift in the treatment paradigm of early-stage colon cancer, and surgery with or without adjuvant chemotherapy should remain the standard approach for these patients.

Curative resection after percutaneous drainage followed by preoperative panitumumab monotherapy for locally advanced sigmoid colon cancer with intra-abdominal abscess: a case report

BACKGROUND

The gold standard treatment for locally advanced colon cancer is curative surgery followed by adjuvant chemotherapy, although this approach is associated with serious concerns, such as high recurrence rates and occasionally unnecessary oversurgery. Neoadjuvant chemotherapy may be a promising strategy for overcoming these issues. This study reports a case of a recurrence-free patient who underwent curative resection without significant organ dysfunction after preoperative chemotherapy for locally advanced sigmoid colon cancer. The tumor coexisted with a large intra-abdominal abscess, and the patient was quite frail at the first visit. We performed percutaneous drainage followed by preoperative panitumumab monotherapy, which yielded favorable outcomes.

CASE PRESENTATION

A 78-year-old frail woman was emergently transferred to our hospital with fever and abdominal pain. The diagnosis was locally advanced sigmoid colon cancer stage IIIC (T4bN2aM0) with a large intra-abdominal abscess. Immediate curative surgery was inappropriate, considering both tumor progression and the patient's frailty. We performed percutaneous drainage and colostomy construction, which was followed by seven cycles of preoperative panitumumab monotherapy without significant adverse events. After these treatments, inflammation was well controlled, and the tumor shrank remarkably. Furthermore, the patient recovered well from frailty; therefore, curative sigmoidectomy combined with resection of the left ovary and stoma closure was possible without any postoperative complications. The final pathological finding was T3N0M0, stage IIA disease. The patient was recurrence-free and had no significant organ dysfunction 21 months after the curative surgery.

CONCLUSIONS

The management of intra-abdominal abscesses and tailor-made preoperative chemotherapy based on the patient's frailty may have been the key factors responsible for the favorable course of this patient. Although further research is needed on the appropriateness of percutaneous drainage for malignancies related to intra-abdominal abscesses and preoperative panitumumab use for locally advanced colon cancer, the study findings can serve as reference for managing similar cases in an aging society.

Time to recurrence and its relation to survival after recurrence in patients resected for stage III colon cancer

BACKGROUND

It is intuitively thought that early relapse is associated with poor survival after recurrence (SAR) in resected colon cancer (CC) patients, but this has never been formally studied.

METHODS

We pooled data from stage III patients treated with oxaliplatin-based adjuvant therapy in two phase III trials, to analyse time to recurrence (TTR) and its relationship with SAR. TTR and SAR were also studied according to molecular status (mismatch repair (MMR), RAS, and BRAFV600E). Early relapsing patients were defined as patients having a TTR event within 12 months after starting adjuvant chemotherapy.

RESULTS

4548 stage III CC patients were included in the present analysis. Deficient MMR (dMMR) CC patients experienced fewer recurrences than proficient (p)MMR CC patients (18.8% versus 27.6%) but had a significantly shorter median TTR (mTTR; 0.74 versus 1.40 years, p < 0.0001). In pMMR patients, BRAF and RAS mutations were also associated with earlier mTTR as compared to double wild-type (WT) patients (0.99 versus 1.38 versus 1.54 years, respectively, p < 0.0001). Early recurrence occurred in 397 patients and was associated with a median SAR (2.2 versus 3.3 years, p = 0.0007). However, this association was mainly due to pMMR/RAS and BRAFV600E mutated tumours and was not confirmed in dMMR and pMMR/double WT subgroups.

CONCLUSION

In resected stage III CC treated with standard oxaliplatin-based adjuvant therapy, TTR varies between dMMR, pMMR/RAS, or BRAFV600E mutated and pMMR/double WT tumours. In addition, early relapse is associated with poor survival, mainly due to patients resected for a pMMR/RAS or BRAFV600E mutated tumour.

The role of ncRNA in the co-regulation of autophagy and exosome pathways during cancer progression

Since its discovery a few decades ago, autophagy has been recognized as a crucial signaling pathway, linked to the recycling of cellular components in nutrient stress. Autophagy is a two-way sword, playing a dual role in tumorigenesis. In this catabolic process, dysfunctional organelles, biomolecules, and misfolded proteins are sequestered in the autophagosome and sent to the lysosome for degradation. Alongside, there are cellular messengers called exosomes, which are released from cells and are known to communicate and regulate metabolism in recipient cells. Multivesicular bodies (MVB) act as the intricate link between autophagy and exosome pathways. The continuous crosstalk between the two pathways is coordinated and regulated by multiple players among which ncRNA is the emerging candidates. The exosomes carry varied cargo of which non-coding RNA exerts an immediate regulatory effect on recipient cells. ncRNA is known to exhibit dual behavior in both promoting and inhibiting tumor growth. There is increasing evidence for the involvement of ncRNAs' in the regulation of different hallmarks of cancer. Different ncRNAs are involved in the co-regulation of autophagy and exosome pathways and therefore represent a superior therapeutic approach to target cancer chemoresistance. Here, we will discuss the ncRNA involved in regulating autophagy, and exosomes pathways and its relevance in cancer therapeutics.

Transcriptomic Signatures of MSI-High Metastatic Colorectal Cancer Predict Efficacy of Immune Checkpoint Inhibitors

PURPOSE

Microsatellite instability (MSI) is currently the only predictive biomarker of efficacy of immune checkpoint inhibitors (ICI) in metastatic colorectal cancers (mCRC). However, 10% to 40% of patients with MSI mCRC will experience a primary resistance to ICI.

EXPERIMENTAL DESIGN

In two cohorts of patients with MSI mCRC treated with ICI (exploratory, N = 103; validation, N = 35), 3' RNA sequencing was performed from primary tumors. Previously described single-cell transcriptomic signatures of tumor microenvironment (TME) were analyzed.

RESULTS

In the exploratory cohort, the unsupervised clustering allowed the identification of three clusters of tumors with distinct transcriptional profiles: cluster A ("stromalHIGH-proliferationLOW"), cluster B ("stromalHIGH-proliferationMED"), and cluster C ("stromalLOW-proliferationHIGH"), with an enrichment of patients progressing at first disease assessment under ICI in cluster A (30% vs. 12% in cluster B and 8.1% in cluster C; P = 0.074). Progression-free survival (PFS) was also significantly shorter in patients belonging to cluster A, compared with clusters B or C (P < 0.001) with 2-year PFS rates of 33.5%, 80.5%, and 78.3%, respectively. In multivariate analysis, PFS was still significantly longer in patients belonging to cluster B [HR, 0.19; 95% confidence interval (CI), 0.08-0.45; P < 0.001] and cluster C (HR, 0.25; 95% CI, 0.10-0.59; P = 0.02), compared with patients belonging to cluster A. The association of this clustering with PFS under ICI was confirmed in the validation cohort. PFS related to non-ICI-based regimens was not significantly different according to cluster.

CONCLUSIONS

This unsupervised transcriptomic classification identified three groups of MSI mCRCs with different compositions of TME cells and proliferative capacities of TME/tumor cells. The "stromalHIGH-proliferationLOW" cluster is associated with a poorer prognosis with ICI treatment.

LM02 trial Perioperative treatment with panitumumab and FOLFIRI in patients with wild-type RAS, potentially resectable colorectal cancer liver metastases-a phase II study

Background

Twenty percent of colorectal cancer liver metastases (CLMs) are initially resectable with a 5-year survival rate of 25%-40%. Perioperative folinic acid, 5-fluorouracil, oxaliplatin (FOLFOX) increases progression-free survival (PFS). In advanced disease, the addition of targeting therapies results in an overall survival (OS) advantage. The aim of this study was to evaluate panitumumab and FOLFIRI as perioperative therapy in resectable CLM.

Methods

Patients with previously untreated, wild-type Rat sarcoma virus (RAS), and resectable CLM were included. Preoperative four and postoperative eight cycles of panitumumab and folinic acid, 5-fluorouracil, irinotecan (FOLFIRI) were administered. Primary objectives were efficacy and safety. Secondary endpoints included PFS and OS.

Results

We enrolled 36 patients in seven centers in Austria (intention-to-treat analyses, 35 patients). There were 28 men and seven women, and the median age was 66 years. About 91.4% completed preoperative therapy and 82.9% underwent liver resection. The R0 resection rate was 82.7%. Twenty patients started and 12 patients completed postoperative chemotherapy. The objective radiological response rate after preoperative therapy was 65.7%. About 20% and 5.7% of patients had stable disease and progressive disease, respectively. The most common grade 3 adverse events were diarrhea, rash, and leukopenia during preoperative therapy. One patient died because of sepsis, and one had a pulmonary embolism grade 4. After surgery, two patients died because of hepatic failure. Most common grade 3 adverse events during postoperative therapy were skin toxicities/rash and leukopenia/neutropenia, and the two grade 4 adverse events were stroke and intestinal obstruction. Median PFS was 13.2 months. The OS rate at 12 and 24 months were 85.6% and 73.3%, respectively.

Conclusions

Panitumumab and FOLFIRI as perioperative therapy for resectable CLM result in a radiological objective response rate in 65.7% of patients with a manageable grade 3 diarrhea rate of 14.3%. Median PFS was 13.2 months, and the 24-month OS rate was 73.3%. These data are insufficient to widen the indication of panitumumab from the unresectable setting to the setting of resectable CLM.

Progress of research on molecular targeted therapies for colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies, accounting for approximately 10% of global cancer incidence and mortality. Approximately 20% of patients with CRC present metastatic disease (mCRC) at the time of diagnosis. Moreover, up to 50% of patients with localized disease eventually metastasize. mCRC encompasses a complex cascade of reactions involving multiple factors and processes, leading to a diverse array of molecular mechanisms. Improved comprehension of the pathways underlying cancer cell development and proliferation, coupled with the accessibility of relevant targeted agents, has propelled advancements in CRC treatment, ultimately leading to enhanced survival rates. Mutations in various pathways and location of the primary tumor in CRC influences the efficacy of targeted agents. This review summarizes available targeted agents for different CRC pathways, with a focus on recent advances in anti-angiogenic and anti-epidermal growth factor receptor agents, BRAF mutations, and human epidermal growth factor receptor 2-associated targeted agents.

Tuna trimmings (Thunnas albacares) hydrolysate alleviates immune stress and intestinal mucosal injury during chemotherapy on mice and identification of potentially active peptides

In this study, Tuna trimmings (Thunnas albacares) protein hydrolysate (TPA) was produced by alcalase. The anti-tumor synergistic effect and intestinal mucosa protective effect of TPA on S180 tumor-bearing mice treated with 5-fluorouracil (5-FU) chemotherapy were investigated. The results showed that TPA can enhance the anti-tumor effect of 5-FU chemotherapy, as evident by a significant reduction in tumor volume observed in the medium and high dose TPA+5-FU groups compared to the 5-FU group (p < 0.001). Moreover, TPA significantly elevated the content of total protein and albumin in all TPA dose groups (p < 0.01, p < 0.001), indicating its ability to regulate the nutritional status of the mice. Furthermore, histopathological studies revealed a significant increase in the height of small intestinal villi, crypt depth, mucosal thickness, and villi area in the TPA+5-FU groups compared to the 5-FU group (p < 0.05), suggesting that TPA has a protective effect on the intestinal mucosa. Amino acid analysis revealed that TPA had a total amino acid content of 66.30 g/100 g, with essential amino acids accounting for 30.36 g/100 g. Peptide molecular weight distribution analysis of TPA indicated that peptides ranging from 0.25 to 1 kDa constituted 64.54%. LC-MS/MS analysis identified 109 peptide sequences, which were predicted to possess anti-cancer and anti-inflammatory activities through database prediction. Therefore, TPA has the potential to enhance the antitumor effects of 5-FU, mitigate immune depression and intestinal mucosal damage induced by 5-FU. Thus, TPA could be serve as an adjuvant nutritional support for malnourished patients undergoing chemotherapy.

Major hurdles to the use of tyrosine kinase inhibitors in clinical prevention/interception studies: Do preclinical studies with EGFR inhibitors suggest approaches to overcome some of the limitations

There are major hurdles to the use of tyrosine kinase inhibitors (TKIs) and any other agents with significant toxicities (which means practically the preponderance of potential effective agents) in the context of prevention/anti-progression (interception) studies. We will discuss epidermal growth factor receptor (EGFR) inhibitors as examples, both in a primary prevention setting, where agent(s) are administered to individuals with no cancer but who might be considered at higher risk due to a variety of factors, and in anti-progression/interception studies, where agent(s) are administered to persons with known preinvasive lesions (e.g., colon adenomas, lung nodules, ductal carcinoma in situ (DCIS), or pancreatic intraepithelial neoplasia (PanIN) lesions in the pancreas) in an attempt to reverse or inhibit progression of these lesions. Multiple potential hurdles will be examined, including: a) toxicity of agents, b) the likely range of subtypes of cancers affected by a given treatment (e.g., EGFR inhibitors against EGFR mutant lung adenocarcinomas), c) the availability of practical endpoints besides the blocking of cancer formation or pharmacokinetics related to the agents administered in a primary prevention study, and d) the interpretation of the regression or blockage of new preinvasive lesions in the anti-progression study. Such an anti-progression approach may help address some of the factors commented on regarding primary prevention (toxicity, potential target organ cancer subtypes) but still leaves major questions regarding interpretation of modulation of preinvasive endpoints when it may not be clear how frequently they progress to clinical cancer. Additionally, we address whether certain recent preclinical findings might be able to reduce the toxicities associated with these agents and perhaps even increase their potential efficacy. Antibodies and TKIs other than the EGFR inhibitors are not discussed because few if any had been tested as monotherapies in humans, making their efficacy harder to predict, and because a number have relatively rare but quite striking toxicities. Furthermore, most of the practical hurdles raised regarding the EGFR inhibitors are relevant to the other TKIs. Finally, we briefly discuss whether early detection employing blood or serum samples may allow identification of high-risk groups more amenable to agents with greater toxicity.

Preoperative Chemotherapy for Operable Colon Cancer: Mature Results of an International Randomized Controlled Trial

PURPOSE

Neoadjuvant chemotherapy (NAC) has potential advantages over standard postoperative chemotherapy for locally advanced colon cancer but requires formal evaluation.

METHODS

Patients with radiologically staged T3-4, N0-2, M0 colon cancer were randomly allocated (2:1) to 6 weeks oxaliplatin-fluoropyrimidine preoperatively plus 18 postoperatively (NAC group) or 24 weeks postoperatively (control group). Patients with RAS-wildtype tumors could also be randomly assigned 1:1 to receive panitumumab or not during NAC. The primary end point was residual disease or recurrence within 2 years. Secondary outcomes included surgical morbidity, histopathologic stage, regression grade, completeness of resection, and cause-specific mortality. Log-rank analyses were by intention-to-treat.

RESULTS

Of 699 patients allocated to NAC, 674 (96%) started and 606 (87%) completed NAC. In total, 686 of 699 (98.1%) NAC patients and 351 of 354 (99.2%) control patients underwent surgery. Thirty patients (4.3%) allocated to NAC developed obstructive symptoms requiring expedited surgery, but there were fewer serious postoperative complications with NAC than with control. NAC produced marked T and N downstaging and histologic tumor regression (all P < .001). Resection was more often histopathologically complete: 94% (648/686) versus 89% (311/351), P < .001. Fewer NAC than control patients had residual or recurrent disease within 2 years (16.9% [118/699] v 21.5% [76/354]; rate ratio, 0.72 [95% CI, 0.54 to 0.98]; P = .037). Tumor regression correlated strongly with freedom from recurrence. Panitumumab did not enhance the benefit from NAC. Little benefit from NAC was seen in mismatch repair-deficient tumors.

CONCLUSION

Six weeks of preoperative oxaliplatin-fluoropyrimidine chemotherapy for operable colon cancer can be delivered safely, without increasing perioperative morbidity. This chemotherapy regimen, when given preoperatively, produces marked histopathologic down-staging, fewer incomplete resections, and better 2-year disease control. Histologic regression after NAC is a strong predictor of lower postoperative recurrence risk so has potential use as a guide for postoperative therapy. Six weeks of NAC should be considered as a treatment option for locally advanced colon cancer.

Current diagnostic and clinical issues of screening for dihydropyrimidine dehydrogenase deficiency

Fluoropyrimidine drugs (FP) are the backbone of many chemotherapy protocols for treating solid tumours. The rate-limiting step of fluoropyrimidine catabolism is dihydropyrimidine dehydrogenase (DPD), and deficiency in DPD activity can result in severe and even fatal toxicity. In this review, we survey the evidence-based pharmacogenetics and therapeutic recommendations regarding DPYD (the gene encoding DPD) genotyping and DPD phenotyping to prevent toxicity and optimize dosing adaptation before FP administration. The French experience of mandatory DPD-deficiency screening prior to initiating FP is discussed.

Lymphovascular invasion represents a superior prognostic and predictive pathological factor of the duration of adjuvant chemotherapy for stage III colon cancer patients

BACKGROUND

Lymphovascular invasion (LVI) and perineural invasion (PNI) can indicate poor survival outcomes in colorectal cancer, but few studies have focused on stage III colon cancer. The current study aimed to confirm the prognostic value of LVI and PNI and identify patients who could benefit from a complete duration of adjuvant chemotherapy based on the two pathological factors.

METHODS

We enrolled 402 consecutive patients with stage III colon cancer who received colon tumor resection from November 2007 to June 2016 at Sun Yat-sen University Cancer Center. Survival analyses were performed by using Kaplan-Meier method with log-rank tests. Risk factors related to disease-free survival (DFS) and overall survival (OS) were identified through Cox proportional hazards analysis.

RESULTS

141 (35.1%) patients presented with LVI, and 108 (26.9%) patients with PNI. The LVI-positive group was associated with poorer 3-year DFS (86.5% vs. 76.3%, P = 0.001) and OS (96.0% vs. 89.1%, P = 0.003) rates compared with the LVI-negative group. The PNI-positive group showed a worse outcome compared with the PNI-negative group in 3-year DFS rate (72.5% vs. 86.7%, P < 0.001). Moreover, LVI-positive group present better 3-year DFS and OS rate in patients completing 6-8 cycles of adjuvant chemotherapy than those less than 6 cycles (3-year DFS: 80.0% vs. 64.9%, P = 0.019; 3-year OS: 93.2% vs. 76.3%, P = 0.002).

CONCLUSIONS

LVI is a superior prognostic factor to PNI in stage III colon cancer patients undergoing curative treatment. PNI status can noly predict the 3-year DFS wihout affecting the 3-year OS. Furthermore, LVI also represents an effective indicator for adjuvant chemotherapy duration.

Biomarkers in the development of individualized treatment regimens for colorectal cancer

Introduction

Colorectal cancer (CRC) is the third most common and second most deadly malignancy in the world with an estimated 1. 9 million cases and 0.9 million deaths in 2020. The 5-year overall survival for stage I disease is 92% compared to a dismal 11% in stage IV disease. At initial presentation, up to 35% of patients have metastatic colorectal cancer (mCRC), and 20–50% of stage II and III patients eventually progress to mCRC. These statistics imply both that there is a proportion of early stage patients who are not receiving adequate treatment and that we are not adequately treating mCRC patients.

Body

Targeted therapies directed at CRC biomarkers are now commonly used in select mCRC patients. In addition to acting as direct targets, these biomarkers also could help stratify which patients receive adjuvant therapies and what types. This review discusses the role of RAS, microsatellite instability, HER2, consensus molecular subtypes and ctDNA/CTC in targeted therapy and adjuvant chemotherapy.

Discussion

Given the relatively high recurrence rate in early stage CRC patients as well as the continued poor survival in mCRC patients, additional work needs to be done beyond surgical management to limit recurrence and improve survival. Biomarkers offer both a potential target and a predictive method of stratifying patients to determine those who could benefit from adjuvant treatment.

Overview of predictive and prognostic biomarkers and their importance in developing a clinical pharmacology treatment plan in colorectal cancer patients

INTRODUCTION

Colorectal cancer (CRC) is the second most common cause of cancer-related death worldwide. Although overall survival for CRC patients has improved with earlier screening, survival continues to vary substantially across stages. Also, while the introduction of targeted therapies, including VEGF and EGFR inhibitors, has contributed to improving survival, better tools are needed to optimize patient selection and maximize therapeutic benefits. Emerging biomarkers can be used to guide pharmacologic decision-making, as well as monitor treatment response, clarify the need for adjuvant therapies, and indicate early signs of recurrence. This is a narrative review examining the current and evolving use of predictive and prognostic biomarkers in colorectal cancer.

AREAS COVERED

Areas covered include mutations of the MAPK (KRAS, BRAF) and HER2 pathways and their impacts on treatment decisions. In addition, novel methods for assessing tumor mutations and tracking treatment responses are examined.

EXPERT OPINION

The standard of care pathway for staging, and treatment selection and surveillance, of CRC will expand to include novel biomarkers in the next 5 years. It is anticipated that these new biomarkers will assist in decision-making regarding selection of targeted therapies and, importantly, in risk stratification for treatment decisions in patients at high risk for recurrence.

Oncological outcomes following minimally invasive surgery for pathological N2M0 colorectal cancer: A propensity score-matched analysis

INTRODUCTION

Whether minimally invasive surgery (MIS) is safe and effective for patients with N2M0 colorectal cancer (CRC) remains controversial. This study aimed to compare short- and long-term outcomes between MIS and open surgery (Open) groups for patients with pathological (p)N2M0 CRC, and evaluate the oncological outcomes of MIS for pN2M0 CRC.

MATERIALS AND METHODS

We retrospectively analyzed 125 consecutive patients with pN2M0 CRC who underwent curative surgery between 2010 and 2017, using propensity score-matching (PSM) analysis.

RESULTS

Median follow-up was 59.4 months. After PSM, we enrolled 68 patients (n = 34 in each group). The conversion rate was 9.6% for the entire patient cohort and 5.9% for the matched cohort. In colon cancer (CC), short-term outcomes were similar between groups. On the other hand, in rectal cancer (RC), estimated blood loss, rate of anastomosis leakage, and length of postsurgical stay were lower in the MIS group than the Open group. R0 resection was achieved in all patients with MIS. No surgical mortality was encountered in any group. No significant differences were found between groups in terms of 3-year local recurrence rate, overall survival, cancer-specific survival, or recurrence-free survival among the entire patient cohort or the matched cohort, regardless of the primary tumor site (CC or RC). Surgical approach (MIS vs Open) had no significant influence on survival outcomes.

CONCLUSIONS

MIS is a safe and effective option for patients with pN2M0 CRC, with acceptable short- and long-term outcomes comparable to the open approach. MIS can be considered for patients with pN2M0 CRC.

Prognostic significance of additional histologic features for subclassification of pathological T3 colon cancer

BACKGROUND

Additional histologic features of T3 colon cancer, such as tumour depth invasion beyond muscularis propria and elastic lamina invasion (ELI), have taken interest for a more accurate staging.

METHODS

Patients with pT3 and pT4a (control group) colon adenocarcinoma were retrospectively collected from our institutional database. The study group was divided according to depth of tumour invasion < 5 mm and ≥ 5 mm, and into ELI - and ELI + . Chi-square test was used to compare the clinicopathological characteristics. OS and DFS were estimated using Kaplan-Meier method and compared with the log-rank test. Univariable and multivariable Cox proportional hazard models were employed to assess the effect on OS and DFS.

RESULTS

Out of 290 pT3 tumours, 168 (58%) had a depth of tumour invasion < 5 mm and 122 (42%) ≥ 5 mm. The 5-year OS and DFS were 85.2, 68.7 and 60.9%, and 81.4, 73.9 and 60.1% in pT3 < 5 mm, pT3 ≥ 5 mm, and pT4a respectively (p = 0.001, p = 0.072). Considering ELI - (n = 157, 54%) and ELI + (n = 133, 46%), the 5-year OS and DFS were 78.9, 76.7, and 60.9%, and 75.5, 81.5, and 60.1% in ELI  - , ELI + and pT4a respectively (p = 0.955, p = 0.462). At multivariable analysis, the depth of invasion was found to be an independent predictive factor for OS (HR 2.04, 95%CI 1.28-3.24, p = 0.003) and DFS (HR 1.98, 95%CI 1.24-3.18, p = 0.004), while ELI did not result a prognostic factor for OS nor DFS.

CONCLUSION

In pT3 colon cancer, depth of tumour invasion ≥ 5 mm is an independent risk factor for OS and DFS, whereas ELI did not result a prognostic factor affecting OS nor DFS.

FOLFOX plus panitumumab or FOLFOX alone as additive therapy following R0/1 resection of RAS wild-type colorectal cancer liver metastases - The PARLIM trial (AIO KRK 0314)

PURPOSE

This trial investigates the addition of panitumumab to chemotherapy with fluorouracil/folinic acid and oxaliplatin (FOLFOX) in a 2:1 randomised, controlled, open-label, phase II trial in RAS wild-type colorectal cancer patients with R0/1-resected liver metastases.

EXPERIMENTAL DESIGN

The primary endpoint was progression-free survival (PFS) two years after randomisation. The experimental arm (12 weeks of biweekly mFOLFOX6 plus panitumumab followed by 12 weeks of panitumumab alone) was considered active if the two-year PFS rate was ≥65%. Based on historical data, a two-year PFS rate of 50% was estimated in the control arm (12 weeks of biweekly FOLFOX). The trial was performed with a power of 80% and an alpha of 0.05. Secondary endpoints included overall survival (OS) and toxicity. The trial is registered with ClinicalTrials.gov, NCT01384994.

RESULTS

The full analysis set consists of 70 patients (pts) in the experimental arm and 36 pts in the control arm. The primary endpoint was missed with a two-year PFS of 35.7% with FOLFOX plus panitumumab and 30.6% in the control arm. In comparative analyses, trends towards improved PFS (HR 0.83; 95%CI, 0.52-1.33; P = 0.44) and OS (HR 0.70; 95% CI, 0.34-1.46; P = 0.34) were observed in favour of the panitumumab-based study arm. No new or unexpected safety signals were observed with FOLFOX plus panitumumab following liver resection.

CONCLUSION

The PARLIM trial failed to demonstrate a two-year PFS rate of 65% after resection of colorectal liver metastases. The positive trends in survival endpoints may support future trials evaluating treatment with anti-EGFR agents after resection of liver metastases.

5FU/Oxaliplatin-Induced Jagged1 Cleavage Counteracts Apoptosis Induction in Colorectal Cancer: A Novel Mechanism of Intrinsic Drug Resistance

Colorectal cancer (CRC) is characterized by early metastasis, resistance to anti-cancer therapy, and high mortality rate. Despite considerable progress in the development of new treatment options that improved survival benefits in patients with early-stage or advanced CRC, many patients relapse due to the activation of intrinsic or acquired chemoresistance mechanisms. Recently, we reported novel findings about the role of Jagged1 in CRC tumors with Kras signatures. We showed that Jagged1 is a novel proteolytic target of Kras signaling, which induces Jagged1 processing/activation resulting in Jag1-ICD release, which favors tumor development in vivo, through a non-canonical mechanism. Herein, we demonstrate that OXP and 5FU cause a strong accumulation of Jag1-ICD oncogene, through ERK1/2 activation, unveiling a surviving subpopulation with an enforced Jag1-ICD expression, presenting the ability to counteract OXP/5FU-induced apoptosis. Remarkably, we also clarify the clinical ineffectiveness of γ-secretase inhibitors (GSIs) in metastatic CRC (mCRC) patients. Indeed, we show that GSI compounds trigger Jag1-ICD release, which promotes cellular growth and EMT processes, functioning as tumor-promoting agents in CRC cells overexpressing Jagged1. We finally demonstrate that Jagged1 silencing in OXP- or 5FU-resistant subpopulations is enough to restore the sensitivity to chemotherapy, confirming that drug sensitivity/resistance is Jag1-ICD-dependent, suggesting Jagged1 as a molecular predictive marker for the outcome of chemotherapy.

Oncological Treatment-Related Fatigue in Oncogeriatrics: A Scoping Review

Fatigue is a highly prevalent symptom in both cancer patients and the older population, and it contributes to quality-of-life impairment. Cancer treatment-related fatigue should thus be included in the risk/benefit assessment when introducing any treatment, but tools are lacking to a priori estimate such risk. This scoping review was designed to report the current evidence regarding the frequency of fatigue for the different treatment regimens proposed for the main cancer indications, with a specific focus on age-specific data, for the following tumors: breast, ovary, prostate, urothelium, colon, lung and lymphoma. Fatigue was most frequently reported using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) versions 3 to 5. A total of 324 regimens were analyzed; data on fatigue were available for 217 (67%) of them, and data specific to older patients were available for 35 (11%) of them; recent pivotal trials have generally reported more fatigue grades than older studies, illustrating increasing concern over time. This scoping review presents an easy-to-understand summary that is expected to provide helpful information for shared decisions with patients regarding the anticipation and prevention of fatigue during each cancer treatment.

Cetuximab and Irinotecan With or Without Bevacizumab in Refractory Metastatic Colorectal Cancer: BOND-3, an ACCRU Network Randomized Clinical Trial

Background

Combination irinotecan and cetuximab is approved for irinotecan-refractory metastatic colorectal cancer (mCRC). It is unknown if adding bevacizumab improves outcomes.

Patients and Methods

In this multicenter, randomized, double-blind, placebo-controlled phase II trial, patients with irinotecan-refractory RAS-wildtype mCRC and no prior anti-EGFR therapy were randomized to cetuximab 500 mg/m², bevacizumab 5 mg/kg, and irinotecan 180 mg/m² (or previously tolerated dose) (CBI) versus cetuximab, irinotecan, and placebo (CI) every 2 weeks until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), and adverse events (AEs).

Results

The study closed early after the accrual of 36 out of a planned 120 patients due to changes in funding. Nineteen patients were randomized to CBI and 17 to CI. Baseline characteristics were similar between arms. Median PFS was 9.7 versus 5.5 months for CBI and CI, respectively (1-sided log-rank P = .38; adjusted hazard ratio [HR] = 0.64; 95% confidence interval [CI], 0.25-1.66). Median OS was 19.7 versus 10.2 months for CBI and CI (1-sided log-rank P = .02; adjusted HR = 0.41; 95% CI, 0.15-1.09). ORR was 36.8% for CBI versus 11.8% for CI (P = .13). Grade 3 or higher AEs occurred in 47% of patients receiving CBI versus 35% for CI (P = .46).

Conclusion

In this prematurely discontinued trial, there was no significant difference in the primary endpoint of PFS between CBI and CI. There was a statistically significant improvement in OS in favor of CBI compared with CI. Further investigation of CBI for the treatment of irinotecan-refractory mCRC is warranted.

Clinical Trial Registration: NCT02292758

Complete Response With Cetuximab-Based Treatment of Metastatic Colorectal Cancers: Two Case Reports and Literature Review

Metastases typically develop before diagnosis and during the treatment of colorectal cancers, while patients with metastatic colorectal cancers (mCRCs) currently have a poor prognosis. In terms of surgical approaches, adjuvant therapies, and targeted therapies, the treatment of mCRCs has had numerous recent advances. As a targeted agent widely used in mCRCs, cetuximab-based treatment is still under dispute due to its side effects and unstable effect. We present two mCRC cases treated with cetuximab-based therapy, of which two patients achieved complete response and without recurrence for over 22 and 84 months, respectively. To better understand the drug usage, we also reviewed the recent achievements and usage precautions of cetuximab in mCRCs. Present and many previous observations support that cetuximab might be a referred drug in the first-line chemotherapy of mCRCs with wild-type RAS and BRAF and proficient mismatch repair.

Pathological complete response after neoadjuvant chemotherapy with FOLFOX for locally advanced sigmoid colon cancer with diverticulitis: A case report

Introduction and importance

The standard treatment for locally advanced colon cancer (LACC) without distant metastasis is curative surgery followed by adjuvant chemotherapy, but the long-term outcomes of this strategy are not satisfactory. Neoadjuvant chemotherapy (NAC) is a promising novel option to overcome this issue. Tumor regression is an expected effect of NAC for LACC, but pathological complete response (pCR) is rare. In this report, we present a rare case of pCR after NAC with FOLFOX for LACC in the sigmoid colon.

Presentation of case

A 66-year-old woman presented to our hospital with fever and abdominal pain. The diagnosis was LACC in the sigmoid colon with possible invasion of the uterus and pelvic wall, stage IIIC (T4bN1bM0). Furthermore, the tumor was complicated by diverticulitis. A colostomy was performed, followed by NAC with FOLFOX. Six cycles were completed without significant adverse events, and the lesion shrunk remarkably. We performed a curative sigmoidectomy without any postoperative complications. Pathological examination revealed no viable cancer cells, indicating pCR.

Discussion

To the best of our knowledge, this is the first report of pCR after NAC for LACC complicated by diverticulitis. Colostomy before NAC, regimen, and cycle of NAC may be the key to this favorable course.

Conclusion

We present a rare case of pathological complete after neoadjuvant chemotherapy with FOLFOX for locally advanced colon cancer in the sigmoid colon complicated by diverticulitis. Our experience may be valuable in determining the optimal treatment strategy for LACC complicated by diverticulitis.

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Neoadjuvant chemotherapy is a promising novel option for locally advanced colon cancer.

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Pathological complete response is rare.

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Indications for cases complicated with diverticulitis are unknown.

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We present a rare case of pCR after NAC for LACC complicated by diverticulitis.

Is Adjuvant Chemotherapy Necessary for Obstructing Stage II Colon Cancer? Results From a Propensity Score Analysis of the French Surgical Association Database

OBJECTIVE

The aim of this study was to compare the survival of patients with stage II obstructing colon cancer (OCC) who had adjuvant chemotherapy with those who did not.

SUMMARY BACKGROUND DATA

The need for adjuvant chemotherapy in stage II colon cancer is still debated.

METHODS

All consecutive patients treated for a stage II OCC in a curative intent (with primary tumor resection) between January 2000 and December 2015 were included in this retrospective, multicenter cohort study which included a propensity score analysis using an odds of treatment weighting (Average Treatment effect on the Treated, ATT). The endpoint was the comparison between the 2 groups for overall survival (OS) and disease-free survival (DFS) according to whether or not patients received adjuvant chemotherapy.

RESULTS

During the study period, 504 patients underwent a curative colectomy for a stage II OCC. Among these patients, 179 (35.5%) had adjuvant chemotherapy and 325 (64.5%) had no adjuvant treatment. Among the 179 patients who received adjuvant chemotherapy, 108 patients (60%) received oxaliplatin based regimen and 99 patients (55%) completed all scheduled cycles. At multivariate analysis, after weighting by the odds (ATT analysis) and adjustment, adjuvant chemotherapy after resection of a stage II OCC was associated with improvements in OS [hazard ratio (HR) = 0.42 (0.17-0.99), P = 0.0498] and DFS [HR = 0.57 (0.37-0.88), P = 0.0116].

CONCLUSION

This study suggests that adjuvant chemotherapy after curative resection of stage II OCC may improve oncological outcomes.

The impact of DNA testing on management of patients with colorectal cancer

Knowledge of the genetic basis of colorectal cancer has evolved over the past decades, allowing for the pre-symptomatic identification of affected patients in those with familial syndromes and to the understanding of the multi-step progression to carcinogenesis in tumors. Knowledge of the genes and pathways involved in colorectal cancer has allowed for targeted therapies in patients in addition to standard chemotherapy for those with metastases. Next-generation sequencing technologies have now also allowed for the sensitive detection of circulating mutations derived from tumors, which can give insight into the presence of residual disease and has implications for changing the standard paradigms for treatment. This article will specifically review advances in targeted therapy in metastatic colon cancer and the progress being made in using circulating tumor DNA in patient management.

Sustainable Clinical Development of Adjuvant Chemotherapy for Colon Cancer

Numerous clinical studies in an adjuvant setting have been conducted and the combination therapy of 5-fluorouracil and oxaliplatin has been established as the standard treatment for Stage III and as an option for high-risk Stage II patients. Biologics such as bevacizumab and antiepidermal growth factor receptor antibodies have failed to show additional survival benefits. The indication of adjuvant chemotherapy has been determined according to the pathological stage. Nevertheless, a pathological diagnosis does not necessarily result in selection of the optimal treatment. To improve treatment decisions, many trials have aimed to stratify patients into treatment groups using genomic testing. Recently, gene signature, Immunoscore, and circulating tumor DNA (ctDNA) assays have been reported and among them, ctDNA was shown to be a promising accurate predictive marker for recurrence. Treatment of ctDNA-positive patients with aggressive chemotherapy may reduce recurrence rates. The ultimate goal is to accurately predict the risk of recurrence and to prevent recurrence in colon cancer patients. In this review we focus on the clinical development of adjuvant chemotherapy and stratification of patients according to risk of recurrence and the future direction of adjuvant chemotherapy.

Pathological Features and Prognostication in Colorectal Cancer

The prognostication of colorectal cancer (CRC) has traditionally relied on staging as defined by the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications. However, clinically, there appears to be differences in survival patterns independent of stage, suggesting a complex interaction of stage, pathological features, and biomarkers playing a role in guiding prognosis, risk stratification, and guiding neoadjuvant and adjuvant therapies. Histological features such as tumour budding, perineural invasion, apical lymph node involvement, lymph node yield, lymph node ratio, and molecular features such as MSI, KRAS, BRAF, and CDX2 may assist in prognostication and optimising adjuvant treatment. This study provides a comprehensive review of the pathological features and biomarkers that are important in the prognostication and treatment of CRC. We review the importance of pathological features and biomarkers that may be important in colorectal cancer based on the current evidence in the literature.

The role of non-coding RNAs in chemotherapy for gastrointestinal cancers

Gastrointestinal (GI) cancers, including colorectal, gastric, hepatic, esophageal, and pancreatic tumors, are responsible for large numbers of deaths around the world. Chemotherapy is the most common approach used to treat advanced GI cancer. However, chemoresistance has emerged as a critical challenge that prevents successful tumor elimination, leading to metastasis and recurrence. Chemoresistance mechanisms are complex, and many factors and pathways are involved. Among these factors, non-coding RNAs (ncRNAs) are critical regulators of GI tumor development and subsequently can induce resistance to chemotherapy. This occurs because ncRNAs can target multiple signaling pathways, affect downstream genes, and modulate proliferation, apoptosis, tumor cell migration, and autophagy. ncRNAs can also induce cancer stem cell features and affect the epithelial-mesenchymal transition. Thus, ncRNAs could possibly act as new targets in chemotherapy combinations to treat GI cancer and to predict treatment response.

Current treatment and surveillance modalities are not sufficient for advanced stage III colon cancer: Result from a multicenter cohort analysis

OBJECTIVE

We conducted this multicenter cohort study to evaluate the current tumor-node-metastasis staging system and treatment modality by analyzing the survival outcomes of patient groups with stage III and IV colon cancer.

PATIENTS AND METHODS

Stage III and IV colon cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database (SEER cohort) and prospectively maintained Sun Yat-sen University (SYSU) cohort were included in this study. Kaplan-Meier method was used to estimate the cumulative rate of overall survival (OS) between patient groups, and the inverse probability weighting method was used to calculated age and sex-adjusted survival curves. The Cox regression model was used to identify the risk factors for OS.

RESULTS

A total of 17,911 and 1135 stage III-IV cases were included in the SEER and SYSU cohorts, respectively. Among them, 1448 and 124 resectable stage IV cases underwent curative-intent treatment in the SEER and SYSU cohorts, respectively. The T4N2b group showed a significantly worse survival outcome compared with the M1a subset receiving curative-intent treatment (HR, 1.46; p < 0.001). This finding was validated in the SYSU cohort, in which the T4N2 group had a worse outcome than that of the M1 group receiving curative-intent treatment (HR, 2.44; p < 0.001). These findings were confirmed in the adjusted survival analysis. In the multivariate analysis, the right-side tumor, poor-undifferentiated tumor, and age over 60 years were identified as independent risk factors for T4N2b patients. Based on this multivariate model, the high-risk T4N2b subgroup had a worse survival outcome compared with resectable M1b patients (HR, 1.24; p = 0.03).

CONCLUSION

By comparing stage III with stage IV colon cancer patients, we identified a subgroup of stage III patients at a higher risk of death than more advanced stages, implying that current cancer care modalities are not sufficient for these high-risk substages.

Advantages and Challenges of Using ctDNA NGS to Assess the Presence of Minimal Residual Disease (MRD) in Solid Tumors

The ability to detect minimal residual disease (MRD) after a curative-intent surgery or treatment is of paramount importance, because it offers the possibility to help guide the clinical decisions related adjuvant therapy. Thus, the earlier MRD is detected, the earlier potentially beneficial treatment can be proposed to patients who might need it. Liquid biopsies, and in particular the next-generation sequencing of circulating tumor DNA (ctDNA) in the blood, have been the focus of an increasing amount of research in the past years. The ctDNA detection at advanced cancer stages is practicable for several solid tumors, and complements molecular information on acquired therapy resistance. In the context of MRD, it is by definition more challenging to detect ctDNA, but it is technically achievable and provides information on treatment response and probability of relapse significantly earlier than standard imaging methods. The clinical benefit of implementing this new technique in the routine is being tested in interventional clinical trials at the moment. We propose here an update of the current use of ctDNA detection by NGS as a tool to assess the presence of MRD and improve adjuvant treatment of solid tumors. We also discuss the main limitations and medium-term perspectives of this process in the clinic.