Finding Waldo: The Evolving Paradigm of Circulating Tumor DNA (ctDNA)—Guided Minimal Residual Disease (MRD) Assessment in Colorectal Cancer (CRC)

Simple Summary

After the surgical removal of colorectal cancer (CRC), residual cancer cells undetectable by standard blood tests and imaging studies are responsible for cancer recurrence. Currently, chemotherapy is often administered after surgery to eradicate residual cancer cells, a decision guided by clinical and pathologic criteria, which are imprecise. Circulating tumor DNA (ctDNA) consists of DNA fragments in the bloodstream derived from cancer cells, and the presence of ctDNA likely indicates the presence of residual cancer cells. The current article discusses how ctDNA technology can help guide treatment in patients with CRC after curative surgery.

Abstract

Circulating tumor DNA (ctDNA), the tumor-derived cell-free DNA fragments in the bloodstream carrying tumor-specific genetic and epigenetic alterations, represents an emerging novel tool for minimal residual disease (MRD) assessment in patients with resected colorectal cancer (CRC). For many decades, precise risk-stratification following curative-intent colorectal surgery has remained an enduring challenge. The current risk stratification strategy relies on clinicopathologic characteristics of the tumors that lacks precision and results in over-and undertreatment in a significant proportion of patients. Consequently, a biomarker that can reliably identify patients harboring MRD would be of critical importance in refining patient selection for adjuvant therapy. Several prospective cohort studies have provided compelling data suggesting that ctDNA could be a robust biomarker for MRD that outperforms all existing clinicopathologic criteria. Numerous clinical trials are currently underway to validate the ctDNA-guided MRD assessment and adjuvant treatment strategies. Once validated, the ctDNA technology will likely transform the adjuvant therapy paradigm of colorectal cancer, supporting ctDNA-guided treatment escalation and de-escalation. The current article presents a comprehensive overview of the published studies supporting the utility of ctDNA for MRD assessment in patients with CRC. We also discuss ongoing ctDNA-guided adjuvant clinical trials that will likely shape future adjuvant therapy strategies for patients with CRC.

Epigenetic insights in the diagnosis, prognosis, and treatment selection in CRC, an updated review

BACKGROUND/AIM

The gradual accumulation of genetic and epigenetic alterations can lead to the development of colorectal cancer. In the last decade much research has been done to discover how methylation as an epigenetic alteration leads to carcinogenesis. While Methylation is a biological process, it can influence gene expression by affecting the promoter activity. This article reviews the role of methylation in critical pathways in CRC.

METHODS

In this study using appropriate keywords, all research and review articles related to the role of methylation on different cancers were collected and analyzed. Also, existing information on methylation detection methods and therapeutic sensitivity or resistance due to DNA methylation were reviewed.

RESULTS

The results of this survey revealed that while Methylation is a biological process, it can influence gene expression by affecting the promoter activity. Promoter methylation is associated with up or downregulation of genes involved in critical pathways, including cell cycle, DNA repair, and cell adherence. Hence promoter methylation can be used as a molecular tool for early diagnosis, improving treatment, and predicting treatment resistance.

CONCLUSION

Current knowledge on potential methylation biomarkers for diagnosis and prognoses of CRC has also been discussed. Our survey proposes that a multi-biomarker panel is more efficient than a single biomarker in the early diagnosis of CRC.

Circulating Tumor DNA Analysis Guiding Adjuvant Therapy in Stage II Colon Cancer

BACKGROUND

The role of adjuvant chemotherapy in stage II colon cancer continues to be debated. The presence of circulating tumor DNA (ctDNA) after surgery predicts very poor recurrence-free survival, whereas its absence predicts a low risk of recurrence. The benefit of adjuvant chemotherapy for ctDNA-positive patients is not well understood.

METHODS

We conducted a trial to assess whether a ctDNA-guided approach could reduce the use of adjuvant chemotherapy without compromising recurrence risk. Patients with stage II colon cancer were randomly assigned in a 2:1 ratio to have treatment decisions guided by either ctDNA results or standard clinicopathological features. For ctDNA-guided management, a ctDNA-positive result at 4 or 7 weeks after surgery prompted oxaliplatin-based or fluoropyrimidine chemotherapy. Patients who were ctDNA-negative were not treated. The primary efficacy end point was recurrence-free survival at 2 years. A key secondary end point was adjuvant chemotherapy use.

RESULTS

Of the 455 patients who underwent randomization, 302 were assigned to ctDNA-guided management and 153 to standard management. The median follow-up was 37 months. A lower percentage of patients in the ctDNA-guided group than in the standard-management group received adjuvant chemotherapy (15% vs. 28%; relative risk, 1.82; 95% confidence interval [CI], 1.25 to 2.65). In the evaluation of 2-year recurrence-free survival, ctDNA-guided management was noninferior to standard management (93.5% and 92.4%, respectively; absolute difference, 1.1 percentage points; 95% CI, -4.1 to 6.2 [noninferiority margin, -8.5 percentage points]). Three-year recurrence-free survival was 86.4% among ctDNA-positive patients who received adjuvant chemotherapy and 92.5% among ctDNA-negative patients who did not.

CONCLUSIONS

A ctDNA-guided approach to the treatment of stage II colon cancer reduced adjuvant chemotherapy use without compromising recurrence-free survival. (Supported by the Australian National Health and Medical Research Council and others; DYNAMIC Australian New Zealand Clinical Trials Registry number, ACTRN12615000381583.).

Translation of IDEA trial results into clinical practice: analysis of the implementation of a new guideline for colon cancer

The IDEA trial showed no clinical relevant differences in efficacy between 3 and 6 months of oxaliplatin‐based adjuvant chemotherapy (ACT) in colon cancer (CC), while toxicity was substantially lower in the 3 months regimen. Therefore, in 2017 the Dutch colorectal cancer guideline was revised and currently recommends 3 months of oxaliplatin‐based ACT. Furthermore, the definition of high‐risk stage II CC was restricted to pT4 tumors. We analyzed changes in ACT between 2015 and 2019. From the Netherlands Cancer Registry all 16 721 patients ≥18 years with resected high‐risk stage II and stage III CC during 2015 to 2019 were selected. Differences in patient and treatment characteristics were analyzed per calendar year according to stage and age. Mean duration of oxaliplatin‐based ACT decreased from 18.6 (±8.0) to 9.5 (±3.8) weeks between 2015 and 2019. In patients receiving ACT (n = 8170), the proportion treated with oxaliplatin increased from 74% to 83%. The proportion of patients receiving ACT was stable, 61% to 69% in stage III and 26% to 29% in pT4 stage II. ACT in previous high‐risk pT3N0 disease decreased from 15% to 3%. Use of oxaliplatin increased from 27% to 49% in patients aged ≥75 years. The revised guideline was rapidly implemented and led to an increase in oxaliplatin‐based ACT in the elderly and increased guideline‐adherence in high‐risk stage II CC.

Impact of Relative Dose Intensity of FOLFOX Adjuvant Chemotherapy on Risk of Death Among Stage III Colon Cancer Patients

BACKGROUND

The National Comprehensive Cancer Network (NCCN) guidelines have recommended tailored chemotherapy for stage III high-risk (T4 and/or N2) and low-risk (T1-T3 and N1) colon cancer since 2018. Studies have investigated the effect of relative dose intensity (RDI) of FOLFOX on stage III colon cancer survival, however, none has performed a stratified analysis by risk profiles. This study aims to identify the FOLFOX optimal RDI for high-risk and low-risk stage III colon cancer patients.

METHODS

Data on 407 eligible patients, diagnosed with stage III colon cancer in 2011 who received FOLFOX, were collected by 8 population-based cancer registries. Multivariable Cox model and Fine-Gray competing risks model were employed to explore Optimal RDI defined as the lowest RDI administered without significant differences in either overall or cause-specific death.

RESULTS

Among the 168 high-risk patients, the optimal RDI cut-off was 70% (HR = 1.59 with 95% CI: 0.69-3.66 in overall mortality; HR = 1.24 with 95% CI: 0.42-3.64 in cause-specific mortality when RDI < 70% vs. RDI ≥ 70%). Among the 239 low-risk patients, none of the evaluated cut-offs were associated with significant differences in risk of death between comparison groups. The lowest assessed RDI was 45%, HR = 0.80; 95% CI: 0.24 to 2.73 for overall mortality and HR = 0.53; 95% CI: 0.06 to 4.95 for cause-specific mortality, when RDI <45% versus RDI ≥45%.

CONCLUSIONS

There is no significant harm on the risk of death when reducing RDI by <30% for high-risk patients. For the low-risk patients, we found that RDI as low as 45% did not significantly affect the risk of death.

Conversion of non-inferiority margin from hazard ratio to restricted mean survival time difference using data from multiple historical trials

The restricted mean survival time measure has gained a lot of interests for designing and analyzing oncology trials with time-to-event endpoints due to its intuitive clinical interpretation and potentially high statistical power. In the non-inferiority trial literature, restricted mean survival time has been used as an alternative measure for reanalyzing a completed trial, which was originally designed and analyzed based on traditional proportional hazard model. However, the reanalysis procedure requires a conversion from the non-inferiority margin measured in hazard ratio to a non-inferiority margin measured by restricted mean survival time difference. An existing conversion method assumes a Weibull distribution for the population survival time of the historical active control group under the proportional hazard assumption using data from a single trial. In this article, we develop a methodology for non-inferiority margin conversion when data from multiple historical active control studies are available, and introduce a Kaplan-Meier estimator-based method for the non-inferiority margin conversion to relax the parametric assumption. We report extensive simulation studies to examine the performances of proposed methods under the Weibull data generative models and a piecewise-exponential data generative model that mimic the tumor recurrence and survival characteristics of advanced colon cancer. This work is motivated to achieve non-inferiority margin conversion, using historical patient-level data from a large colon cancer clinical database, to reanalyze an internationally collaborated non-inferiority study that evaluates 6-month versus 3-month duration of adjuvant chemotherapy in stage III colon cancer patients.

Microsatellite instability and chemosensitivity in solid tumours

The use of biomarkers that influence a targeted choice in cancer treatments is the future of medical oncology. Within this scenario, in recent years, an important role has been played by knowledge of microsatellite instability (MSI), a molecular fingerprint that identifies defects in the mismatch repair system. This knowledge has changed clinical practice in the adjuvant setting of colon cancer, and its role in the neoadjuvant setting in gastric tumours is becoming increasingly interesting, as well as in endometrial cancers in both early and advanced diseases. Furthermore, it has undoubtedly conditioned the first lines of treatment in the metastatic setting in different types of cancers. The incidence of MSI is different in different cancer types, as well as in early cancers versus metastatic disease. Knowing the incidence of MSI in the various histologies can provide insight into the potential use of this biomarker considering its prognostic value, especially in the early stages, and its predictive role with respect to treatment response. In particular, MSI can guide the choice of chemotherapy treatments in the adjuvant setting of colon and perioperative setting in gastric tumours, which could lead to immunotherapy treatments in these patients in both the early stages of the disease and the metastatic setting where the response to immunotherapy drugs in diseases with MSI is now well established. In this review, we focus on colon, gastric and endometrial cancers, and we briefly discuss other cancer types where MSI could have a potential role in oncological treatment decisions.

Microsatellite Instability and Metastatic Colorectal Cancer - A Clinical Perspective

Approximately 4-5% of patients with metastatic colorectal cancer (mCRC) have mismatch repair deficient (dMMR)/microsatellite instability-high (MSI-H) tumours. These tumours present challenges in the clinical practice due to variant response to fluoropyrimidine-based chemotherapy and, perhaps, also non-immunologic targeted therapies. Recently, a breakthrough in the treatment of dMMR/MSI-H mCRC has been achieved with several clinical trials showing dramatic long-term benefit of immunotherapy using checkpoint inhibitors. Nevertheless, several questions remain regarding the optimisation of immunotherapy regimens and the use of biomarkers to identify populations set to derive the greatest benefit from immunotherapy. Combination regimens and/or the use of immunotherapy as a maintenance after induction non-immunologic systemic therapy may be the way forward to improve outcomes.

Copy-number heterogeneity as high-risk feature of stage II colon cancer

Overall, the prognosis of patients suffering from stage II colon cancer is relatively favorable. However, a proportion of patients develop a recurrence following surgery. Clinical and histopathological properties that identify high‐risk patients are of limited value and better biomarkers are urgently required. In a recent issue of The Journal of Pathology, Lahoz et al proposed that copy‐number‐based biomarkers could be employed for patient stratification. The authors studied copy‐number alterations (CNAs) at the genomic scale by measuring the total CNA load (the aberrant genome fraction), and at a smaller scale by identifying common arm‐ or cytoband‐level alterations. Both the overall CNA load and specific chromosomal regions were associated with an increased risk of recurrence. Most interestingly, it was demonstrated that copy‐number intratumor heterogeneity, as defined by subclonal CNAs, is associated with poor disease outcome. This study demonstrates that structural genomic aberrations are promising biomarkers for patient stratification in early colon cancer. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

New diagnostic measures of oxaliplatin-induced peripheral sensory neuropathy

OBJECTIVE

Oxaliplatin-induced peripheral neuropathy (OIPN) is an unwanted side effect of oxaliplatin chemotherapy treatment. OIPN manifests in an acute phase that lasts a few days after injection and a persistent phase that may become chronic. Currently, there is no consensus about a clinically applicable, quantitative, and objective measure of OIPN.

METHODS

Seventeen patients treated with oxaliplatin containing adjuvant chemotherapy for stage III colon cancer, but otherwise healthy, were tested with six quantitative sensory tests (QST) and five large fibre perception threshold tracking (PTT) measures (quantified by, e.g., rheobase and electrotonus threshold) one hour before each of the 12 chemotherapy cycles given at two weeks' intervals. These measures were repeated at 3, 6, and 12-month follow-ups. The temporal development of OIPN assessed by the Common Terminology Criteria for Adverse Events (CTCAE) scale, QST, and PTT measures was calculated by linear regression.

RESULTS

The CTCAE score showed a tri-phasic increase during the treatment and remained increased during the follow-up. The vibration threshold (R = 0.25, p<0.001), the cold pain threshold (R = 0.17, p = 0.02), and the rheobase (R = 0.28, p < 0.001) increased during treatment, whereas the cold detection threshold (R=-0.16, p = 0.002) decreased. The cold pain threshold and the rheobase remained increased, and the cold detection and heat pain threshold remained decreased during follow-up.

CONCLUSIONS

Increased cold pain sensitivity and decreased large fibre sensitivity (increased rheobase) correlate to the persistent OIPN, whereas the CTCAE score assesses both acute and persistent OIPN. Furthermore, the novel PTT method assessed the nerve excitability changes caused by the oxaliplatin.

CDX2 Biomarker Testing and Adjuvant Therapy for Stage II Colon Cancer: An Exploratory Cost-Effectiveness Analysis

OBJECTIVES

Adjuvant chemotherapy is not recommended for patients with average-risk stage II (T3N0) colon cancer. Nevertheless, a subgroup of these patients who are CDX2-negative might benefit from adjuvant chemotherapy. We evaluated the cost-effectiveness of testing for the absence of CDX2 expression followed by adjuvant chemotherapy (fluorouracil combined with oxaliplatin [FOLFOX]) for patients with stage II colon cancer.

METHODS

We developed a decision model to simulate a hypothetical cohort of 65-year-old patients with average-risk stage II colon cancer with 7.2% of these patients being CDX2-negative under 2 different interventions: (1) test for the absence of CDX2 expression followed by adjuvant chemotherapy for CDX2-negative patients and (2) no CDX2 testing and no adjuvant chemotherapy for any patient. We derived disease progression parameters, adjuvant chemotherapy effectiveness and utilities from published analyses, and cancer care costs from the Surveillance, Epidemiology, and End Results (SEER)-Medicare data. Sensitivity analyses were conducted.

RESULTS

Testing for CDX2 followed by FOLFOX for CDX2-negative patients had an incremental cost-effectiveness ratio of $5500/quality-adjusted life-years (QALYs) compared with no CDX2 testing and no FOLFOX (6.874 vs 6.838 discounted QALYs and $89 991 vs $89 797 discounted US dollar lifetime costs). In sensitivity analyses, considering a cost-effectiveness threshold of $100 000/QALY, testing for CDX2 followed by FOLFOX on CDX2-negative patients remains cost-effective for hazard ratios of <0.975 of the effectiveness of FOLFOX in CDX2-negative patients in reducing the rate of developing a metastatic recurrence.

CONCLUSIONS

Testing tumors of patients with stage II colon cancer for CDX2 and administration of adjuvant treatment to the subgroup found CDX2-negative is a cost-effective and high-value management strategy across a broad range of plausible assumptions.

Oxaliplatin-based adjuvant chemotherapy rather than fluorouracil-based chemotherapy in rectal cancer is more efficient to decrease distant metastasis and increase survival after preoperative chemoradiotherapy and surgery: a meta-analysis

PURPOSE

The standard treatment of stage II-III rectal cancer is preoperative chemoradiotherapy (CRT), followed by total mesorectal excision (TME). However, the rate of metastasis is still high following this treatment. Therefore, several adjuvant chemotherapy studies have been conducted on reducing subsequent metastases and increasing survival, although there are still no definite conclusions.

METHODS

We searched for published prospective randomized controlled trials comparing adjuvant chemotherapy regimens following standard preoperative CRT and curative surgery in stage II-III rectal cancer. We systematically searched Medline, Embase, and the Cochrane Library for relevant trials done from January 2004 to January 2021. Review Manager (RevMan, version 5.3) was used to analyze the data.

RESULTS

We initially searched 1955 studies. We screened and carefully selected four randomized controlled trials with 2897 patients. Compared to the 5-FU-based regimen group, the oxaliplatin-added regimen group attained a higher 3-year locoregional control rate (relative risk [RR] of 0.64, 95% confidence interval [CI], 0.48-0.86; p = 0.003) and 3-year distant metastasis control rate (RR of 0.82, 95% CI, 0.71-0.95; p = 0.007). The oxaliplatin-added regimen group had significantly increased 3-year disease-free survival with a hazard ratio (HR) of 0.85 (95% CI: 0.74-0.97, p = 0.020), but not overall survival (p = 0.740). Grade 3 or higher acute toxicity rates did not differ between the two groups (p = 0.190).

CONCLUSION

The addition of oxaliplatin to adjuvant therapy for stage II-III rectal cancer following preoperative CRT and TME may increase disease-free survival without significant increases in toxicity, but not overall survival.

Validation of IL-7R as an Immunological Biomarker for Human Pancreatic Ductal Adenocarcinoma

Simple Summary

Despite being the fourth-leading cause of cancer-related deaths worldwide, pancreatic ductal adenocarcinoma (PDAC) lacks early diagnostic methods. We performed mRNA sequencing on peripheral blood mononuclear cells isolated from PDAC patients and identified IL-7R as a potential early diagnostic biomarker for PDAC. Furthermore, we found that IL-7R had improved diagnostic performance when combined with CA19-9. Our previous study’s results with 23 individuals were validated in a cohort of 522 patients. Our findings suggested that IL-7R in combination with CA19-9 could have important clinical implications that contribute to an earlier PDAC diagnosis and improved patient survival.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer for which no early diagnostic method is available. The immune surveillance hypothesis suggests that the immune system plays crucial roles in tumor development and progression. We validated a PDAC-specific biomarker derived from peripheral blood mononuclear cells (PBMCs) to facilitate early PDAC diagnosis. mRNA levels of interleukin-7R (IL-7R), reportedly a potential immunological marker for PDAC, were measured in PBMCs isolated prospectively from healthy controls (n = 100) and patients with PDAC (n = 135), pancreatic cysts (n = 82), chronic pancreatitis (n = 42), acute pancreatitis (n = 47), and other malignancies (n = 116). The IL-7R level was significantly higher in patients with PDAC than in healthy controls, patients with benign pancreatic disease, and patients with other malignancies. As diagnostic parameters, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for IL-7R were 58.5%, 92%, 90.8%, 62.2%, and 72.8%, respectively. The area under the receiver operating characteristic curve (AUROC) was 0.766. IL-7R levels did not differ between resectable and unresectable PDAC cases. The combined measurement of IL-7R and carbohydrate antigen 19-9 (CA19-9) significantly improved the diagnostic parameters and AUROC compared with the use of IL-7R or CA19-9 alone. IL-7R is significantly upregulated in PBMCs in patients with PDAC, and it may be a novel diagnostic marker for PDAC. The combined use of IL-7R and CA19-9 enhanced the diagnostic performance.

Aldehyde Dehydrogenase 2 Family Member (ALDH2) Is a Therapeutic Index for Oxaliplatin Response on Colorectal Cancer Therapy with Dysfunction p53

Oxaliplatin resistance is a major issue in the treatment of p53 mutant colorectal cancer (CRC). Finding the specific biomarkers would improve therapeutic efficacy of patients with CRC. In order to figure out the biomarker for CRC patients with mutant p53 access oxaliplatin, a Gene Expression Omnibus dataset (GSE42387) was used to determine differentially expressed genes (DEGs). The Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape software were used to predict protein-protein interactions. The Database for Annotation, Visualization, and Integrated Discovery online tool was used to group the DEGs into their common pathways. 138 DEGs were identified with 46 upregulated and 92 downregulated. In the PPI networks, 7 of the upregulated genes and 13 of the downregulated genes were identified as hub genes (high degrees). Four hub genes, aldehyde dehydrogenase 2 family member (ALDH2), aldo-keto reductase family 1 member B1 (AKR1B1), aldo-keto reductase family 1 member B10 (AKR1B10), and monoglyceride lipase (MGLL) were enriched in the most significant pathway, glycerolipid metabolism. Further, we found that low expression of ALDH2 is correlated with poor overall survival and oxaliplatin resistance. Finally, we found that combined treatment with ALDH2 inhibitor and oxaliplatin will reduce the sensitivity to oxaliplatin in p53 mutant HT29 cells. In conclusion, we demonstrate that ALDH2 may be a biomarker for oxaliplatin resistance status in CRC patients and bring new insight into treatment strategy for p53 mutant CRC patients.

Identification of an ACK1/TNK2-based prognostic signature for colon cancer to predict survival and inflammatory landscapes

Activated Cdc42-associated kinase 1 (ACK1), a kind of tyrosine kinase, is considered to be an oncogene in many cancers, and it is likely to become a potential target for cancer treatment. We found that the expression of the ACK1 gene in colon cancer was higher than that in normal tissues adjacent to cancer, and high expression of the ACK1 gene was associated with poor prognosis of patients. We assessed the prognosis of colon cancer based on ACK1-related genes and constructed a model that can predict the prognosis of colon cancer patients in colon cancer data from The Cancer Genome Atlas (TCGA) database. We then explored the relationship between ACK1 and the immune microenvironment of colon cancer. The overexpression of ACK1 might hinder the function of antigen-presenting cells. The colon cancer prognosis prediction model we constructed has certain significance for clinicians to judge the prognosis of patients with colon cancer. The expression of the ACK1 gene might affect the infiltration level of a variety of immune cells and immunomodulators in the immune microenvironment.

Survival benefit with adjuvant chemotherapy in stage III microsatellite-high/deficient mismatch repair colon cancer: a systematic review and meta-analysis

Clinical observations have demonstrated that microsatellite instability-high (MSI-H) and/or deficient MMR (dMMR) status are associated with favorable prognosis and no benefit from 5-Fluorouracil (5-FU)-based adjuvant chemotherapy in patients with resected stage II colorectal cancer (CRC). This study represents a systematic review and meta-analysis exploring the predictive role of MSI-H status in stage III CRC undergoing or not adjuvant chemotherapy. Published articles that evaluated the role of adjuvant chemotherapy in resected stage III CRC from inception to September 2020 were identified by searching the PubMed, EMBASE, and Cochrane Library databases. The random-effects model was conducted to estimate the pooled effect size of OS and DFS. The primary outcome of interest was OS. 21,590 patients with MSI-H/dMMR stage III CRC, from n = 17 retrospective studies, were analyzed. Overall, OS was improved with any adjuvant chemotherapy vs. any control arm (single-agent 5-FU or surgery alone): HR 0.42, 95% CI 0.26–0.66; P < 0.01. Conversely, DFS was not significantly improved (HR 0.7, 95% CI 0.45–1.09; P = 0.11). In patients with stage III MSI-H/dMMR CRC, adjuvant chemotherapy is associated with a significant OS improvement. Thus, MSI-H/dMMR status does represent a predictive factor for postoperative chemotherapy benefit in stage III CRC beyond its prognostic role.

Post-Marketing Surveillance of a generic Oxaliplatin (AlvoxalⓇ) in Iranian Patients with Cancer

Background

CRC is the second and third most common cancer in women and men, respectively. The national comprehensive cancer network guidelines recommend oxaliplatin-based chemotherapy as a preferred regimen for patients with advanced or metastatic colon cancer. Oxaliplatin is also used in the off-label treatment of gastric cancer. FDA uses post-marketing study commitments to gather additional information about a product's safety, efficacy, or optimal use. It is necessary to perform safety monitoring after marketing authorization is received; such monitoring can be done by means of characterizing the safety of drugs in patients being treated in real-world clinical practice settings.

Objectives

This Phase IV study aimed to evaluate the safety profile of a brand-name formulation of the generic drug oxaliplatin (Alvoxal^Ⓡ, NanoAlvand, Tehran, Iran) in Iranian patients diagnosed with either colorectal or other, different types of cancer.

Methods

Patients with colorectal cancer, gastric cancer, or other malignancies receiving oxaliplatin as a part of their treatment were included in this open-label, multicenter, observational Phase IV study. This study aimed to assess the safety profile of oxaliplatin in patients diagnosed with different cancers.

Findings

A total of 483 patients from 16 cities in Iran were enrolled. The most common malignancy was colorectal cancer (55.49%), followed by gastric cancer (28.16%). Based on the results, 405 patients experienced at least 1 adverse event. Most of these adverse events were grade 1 or 2, and the most commonly reported adverse event was anemia (60.66%). During the study, 26 serious adverse events occurred in 15 (3.11%) patients, which were perhaps related to oxaliplatin. There were no remarkable differences in the incidences of adverse events in the system organ classes of blood and lymphatic system disorders, gastrointestinal disorders, or nervous system disorders among patients with different malignancies (ie, colorectal cancer, gastric cancer, and other malignancies) or between genders. The results of this open-label, multicenter, observational, postmarketing surveillance study demonstrated no unexpected safety findings from the use of this oxaliplatin product (Alvoxal^Ⓡ) in Iranian patients diagnosed with different types of cancer.

Conclusions

This Phase IV study provides data on the safety profile of a number of chemotherapy regimens containing an oxaliplatin product given to Iranian patients diagnosed with different types of cancer.

OUP accepted manuscript

Background

The survival impact of multi-agent (MAC) compared with single-agent (SAC) adjuvant chemotherapy (AC) in elderly patients with stage III colon cancer (CC) remains controversial. The aim of this study was to compare survival outcomes of MAC and SAC in this population utilizing the National Cancer Database (NCDB).

Patients and Methods

Patients aged ≥70 years with pathological stage III CC diagnosed in 2004-2015 were identified in the NCDB. Univariate and multivariable analyses were conducted, and Kaplan-Meier analysis and Cox proportional hazard models were used to identify associations between MAC vs. SAC and overall survival (OS).

Results

Among 41 707 elderly patients (≥70 years old) with stage III CC, about half (n = 20 257; 48.5%) received AC; the majority (n = 12 923, 63.8%) received MAC. The median age was 79 (range 70-90). The majority were female (n = 11 201, 55.3%), Caucasians (88%) and had moderately differentiated tumor grade (n = 12 619, 62.3%), tumor size >4 cm (11 785, 58.2%), and negative surgical margins (18 496, 91.3%). Low-risk stage III CC constituted 50.6% (n = 10 264) of the study population. High-risk stage III CC was associated with worse OS compared with low-risk disease (HR 0.35, 0.34-0.36, P < .001). Multi-agent chemotherapy was associated with a better 5-year OS compared with SAC (P < .001). High-risk stage III patients who received MAC vs. SAC had an OS of 4.2 vs. 3.4 years, respectively (P < .001). Low-risk stage III patients who received MAC vs. SAC had a median OS of 8.5 vs. 7 years (P < .001). In univariate and multivariable analyses, male sex, positive surgical margin, insurance and facility types, age, year of diagnosis, tumor size, and Charlson-Deyo score of >2 were associated with worse OS (P < .05).

Conclusions

Any adjuvant chemotherapy has a trend of survival benefits. Multi-agent chemotherapy seems to have an enhanced benefit in the 70-75 age group. Multi-agent chemotherapy seemed to have similar efficacy as SAC in those aged >76 years.

Hyaluronic Acid May Be a Predictive Biomarker for Thrombocytopenia and Liver Dysfunction After Oxaliplatin-based Chemotherapy

BACKGROUND/AIM

Following oxaliplatin-based chemotherapy, approximately half of all colorectal cancer patients develop sinusoidal obstruction syndrome (SOS). SOS can be monitored by measuring splenic volume; however, obtaining this measurement is not a simple process. In this study, we evaluated changes in hyaluronic acid (HA) concentrations as a simpler marker of SOS.

PATIENTS AND METHODS

We measured splenic volume and laboratory data, including hyaluronic acid concentration, liver enzymes, and platelet counts, in 34 patients with colorectal cancer who underwent radical resection and who received capecitabine plus oxaliplatin (CapeOx) chemotherapy.

RESULTS

A strong correlation was identified between ≥30% increase in splenic volume and significantly elevated HA concentrations. Affected patients also had persistent thrombocytopenia and liver dysfunction compared to patients without elevated HA concentration.

CONCLUSION

HA concentration may predict SOS in patients who receive CapeOx adjuvant chemotherapy.

Effectiveness of oral fluoropyrimidine monotherapy as adjuvant chemotherapy for high-risk stage II colon cancer

Purpose

Methods

Results

Conclusion

Clinical implication of adjuvant chemotherapy according to mismatch repair status in patients with intermediate-risk stage II colon cancer

Background

The present study evaluated the clinical implications of adjuvant chemotherapy according to the mismatch repair (MMR) status and clinicopathologic features of patients with intermediate- and high-risk stage II colon cancer (CC).

Methods

This study retrospectively reviewed 5,774 patients who were diagnosed with CC and underwent curative surgical resection at Kyungpook National University Chilgok Hospital. The patients were enrolled according to the following criteria: (1) pathologically diagnosed with primary CC; (2) stage II CC classified based on the 7th edition of the American Joint Committee on Cancer staging system; (3) intermediate- and high-risk features; and (4) available test results for MMR status. A total of 286 patients met these criteria and were included in the study.

Results

Among the 286 patients, 54 (18.9%) were identified as microsatellite instability-high (MSI-H) or deficient MMR (dMMR). Although all the patients identified as MSI-H/dMMR showed better survival outcomes, T4 tumors and adjuvant chemotherapy were identified as independent prognostic factors for survival. For the intermediate-risk patients identified as MSI-low (MSI-L)/microsatellite stable (MSS) or proficient MMR (pMMR), adjuvant chemotherapy exhibited a significantly better disease-free survival (DFS) but had no impact on overall survival (OS). Oxaliplatin-containing regimens showed no association with DFS or OS. Adjuvant chemotherapy was not associated with DFS in intermediate-risk patients identified as MSI-H/dMMR.

Conclusion

The current study found that the use of adjuvant chemotherapy was correlated with better DFS in MSI-L/MSS or pMMR intermediate-risk stage II CC patients.

In vitro and in vivoactivity of series of cationic dinuclearPt(II) complexes

The antitumour potential of nine dinuclear platinum(II) complexes of the type [{Pt(L)Cl}2(μ-X)]2+(where L represents two NH3 or different bidentantly coordinated diamine ligand - ethylenediamine, en; (±)-1,2-propylenediamine, 1,2-pn; isobutylenediamine, ibn; trans-(±)-1,2-diaminocyclohexane, dach; 1,3-propylenediamine, 1,3-pd; 2,2-dimethyl-1,3-propylenediamine, 2,2-diMe-1,3-pd; (±)-1,3-pentanediamine,1,3-pnd, and X is a bridging pyrazine (pz) or pyridazine (pydz) ligand) were determined by in vitro and in vivo assays using the CT26 cell line and a murine model of heterotopic colon cancer tumour induced in immunocompetent BALB/c mice. This study concludes that complexes Pt1, Pt2 and Pt7 possess significant in vitro cytotoxic activity against mouse colon carcinoma CT26 cells, while all these complexes show moderate apoptotic effect. Complexes Pt1 and Pt7 arrested CT26 cells in G2/M phase of cell cycle, while, evaluated by detection of Ki67 expressing cells, complexes Pt5 and Pt6 exerted the highest antiproliferative effect. Complexes Pt1 and Pt2 exerted significant in vivo antitumour effects. These complexes reduced the growth of primary tumour and the incidence of lung and liver metastases without causing the significant hepato- and nephro- toxicity. Our data indicate considerable antitumour activity of platinum(II) complexes against CT26 cells in vitro and in vivo and imply possible further investigations on their role as potential chemotherapeutic agents.

Detecting Liquid Remnants of Solid Tumors: Circulating Tumor DNA Minimal Residual Disease

Growing evidence demonstrates that circulating tumor DNA (ctDNA) minimal residual disease (MRD) following treatment for solid tumors predicts relapse. These results suggest that ctDNA MRD could identify candidates for adjuvant therapy and measure response to such treatment. Importantly, factors such as assay type, amount of ctDNA release, and technical and biological background can affect ctDNA MRD results. Furthermore, the clinical utility of ctDNA MRD for treatment personalization remains to be fully established. Here, we review the evidence supporting the value of ctDNA MRD in solid cancers and highlight key considerations in the application of this potentially transformative biomarker.

SIGNIFICANCE

ctDNA analysis enables detection of MRD and predicts relapse after definitive treatment for solid cancers, thereby promising to revolutionize personalization of adjuvant and consolidation therapies.

Predictive risk-score model for selection of patients with high-risk stage II colon cancer for adjuvant systemic therapy

BACKGROUND

Adjuvant systemic therapy is selectively considered for high-risk stage II colon cancer, but which patients benefit most from adjuvant systemic therapy is unclear.

METHODS

Patients who underwent resection of stage II colon cancer were identified from the National Cancer Database (2010-2016). Risk-factors for decreased overall survival on multivariable analysis were used to establish a predictive risk-score model for all-cause mortality. After propensity matching within each risk group, 5-year overall survival was estimated based on receipt of adjuvant systemic therapy.

RESULTS

Of the 15,241 patients evaluated, 2,857 (18.8%) received adjuvant systemic therapy. Risk factors for decreased overall survival included age >75 (hazard ratio 3.3, P < .001), male sex (hazard ratio 1.2, P < .001), White/Black race (hazard ratio 1.4, P = .020), preoperative carcinoembryonic antigen >3.5 ng/mL (hazard ratio 1.6, P < .001), T4a T-stage (hazard ratio 2.0, P < .001), T4b T-stage (hazard ratio 2.4, P < .001), lymphovascular invasion (hazard ratio 1.2, P = .003), perineural invasion (hazard ratio 1.3, P = .003), and non-R0 proximal/distal resection margins (hazard ratio 1.7, P < .001). An internally validated risk-score model using these factors was developed composed of low-risk (n = 8,489), moderate-risk (n = 4,623), and high-risk (n = 2,129) groups; within each group, 19.9%, 15.7%, and 20.8% of patients, respectively, received adjuvant systemic therapy. After propensity matching, adjuvant systemic therapy was not associated with improved 5-year overall survival for low-risk patients (89.8% vs 88.3%, P = .280), but was for moderate-risk (80.5% vs 70.8%, P < .001), and high-risk (65.2% vs 45.7%, P < .001) patients.

CONCLUSION

A predictive risk-score model incorporating patient and tumor factors identifies a high-risk cohort of stage II colon cancer patients who may benefit from adjuvant systemic therapy, although the minority of these patients appear to be receiving treatment.

Clinicopathological and Molecular Characteristics of Early-Onset Stage III Colon Adenocarcinoma: An Analysis of the ACCENT Database

BACKGROUND

Colon cancer (CC) incidence in young adults (age 20-49 years), termed early-onset CC (EO-CC), is increasing.

METHODS

Individual patient data on 35 713 subjects with stage III colon cancer from 25 randomized studies in the Adjuvant Colon Cancer ENdpoint database were pooled. The distributions of demographics, clinicopathological features, biomarker status, and outcome data were summarized by age group. Overall survival, disease-free survival, time to recurrence, and survival after recurrence were assessed by Kaplan-Meier curves and Cox models stratified by treatment arms within studies, adjusting for sex, race, body mass index, performance status, disease stage, grade, risk group, number of lymph nodes examined, disease sidedness, and molecular markers. All statistical tests were 2-sided.

RESULTS

Using a 5% difference between age groups as the clinically meaningful cutoff, patients with stage III EO-CC had similar sex, race, performance status, risk group, tumor sidedness, and T stage compared with patients with late-onset CC (age 50 years and older). EO-CC patients were less likely to be overweight (30.2% vs 36.2%) and more commonly had 12 or more lymph nodes resected (69.5% vs 58.7%). EO-CC tumors were more frequently mismatch repair deficient (16.4% vs 11.5%) and less likely to have BRAFV600E (5.6% vs 14.0%), suggesting a higher rate of Lynch syndrome in EO-CC. Patients with EO-CC had statistically significantly better overall survival (hazard ratio [HR] = 0.81, 95% confidence interval [CI] = 0.74 to 0.89; P < .001), disease-free survival (HR = 0.91, 95% CI = 0.84 to 0.98; P = .01), and survival after recurrence (HR = 0.88, 95% CI = 0.80 to 0.97; P = .008) in the analysis without molecular markers; however, age at onset of CC lost its prognostic value when outcome was adjusted for molecular markers.

CONCLUSION

Tumor biology was found to be a more important prognostic factor than age of onset among stage III colon cancer patients in the Adjuvant Colon Cancer ENdpoint database.

Adjuvant treatment of colon cancer with microsatellite instability - the state of the art

Adjuvant chemotherapy with fluoropyrimidine (FP) plus oxaliplatin in stage III resected colorecatal cancer (RCRC) resulted in a 30% relative reduction of disease recurrence risk and mortality. The presence of altered mismatch repair genes identify tumors with microsatellite instability (MSI) that have a better prognosis than stable tumors, but data about adjuvant chemotherapy benefit in this subgroup are compelling. We investigate the role of adjuvant therapy in resected MSI RCRC. The standard treatment is the association of FP plus oxaliplatin, while it can avoided in low risk stage II, thanks to its good prognosis. We propose a practice strategy to approach MSI RCRC in line with the current knowledge. In consideration of the dramatic results in chemorefractory MSI metastatic CRC, there are assumptions that immunotherapy can become a potential alternative to classical systemic therapies also in the adjuvant setting. We await the results of ongoing studies to draw further conclusions."

Outcomes of Cytoreduction and Oxaliplatin-Based Hyperthermic Intraperitoneal Chemotherapy in Patients With Peritoneal Carcinomatosis From Colorectal Cancer

Among patients with metastatic colorectal cancer, 25% have isolated peritoneal carcinomatosis. We performed a systematic review and meta-analysis to assess the disease-free survival (DFS) and overall survival (OS) of patients undergoing hyperthermic intraperitoneal chemotherapy with oxaliplatin. Eleven studies were included in the final assessment. Pooled three- and five-year OS rates were 58.60% and 42.19%, respectively. The estimated pooled three- and five-year DFS rates were 23.47% and 14.26%, respectively.

[Neoadjuvant and adjuvant therapy of resectable colon cancer - Current standards and developments]

The present review focusses on perioperative diagnosis and treatment of resectable colon cancer. In UICC stages associated with a higher risk of recurrence, adjuvant chemotherapy after resection of the primary tumor is an established standard. While initial data also indicate the benefit of Neoadjuvant, pre-operative chemotherapy, a final evaluation is still pending. The main focus of molecular testing in the perioperative setting is the analysis of microsatellite instability, which should routinely be performed in defined subgroups. In UICC stage II without risk factors, adjuvant therapy has a limited benefit and therefore is not a preferred option. In UICC stage II with risk factors, adjuvant therapy can be performed. The approach here is based on the recommendations applicable to stage III. In UICC stage III with low risk, adjuvant chemotherapy with CAPOX for 3 months is preferentially recommended. In UICC stage III with high risk, adjuvant chemotherapy over 6 months is recommended, preferentially with FOLFOX. Microsatellite instability (MSI) is clearly associated with favorable prognosis in non-metastatic colon cancer. However, it cannot be considered a predictive factor for the efficacy of adjuvant chemotherapy. Specifically, recent data of the IDEA study have opened the arena for shared decision making between physicians and patients allowing to define individual treatment approaches based on common assessment of risks and benefits. After completion of perioperative treatment, structured follow-up is of great importance and should be carried out according to the recommendations of the S3 guideline.

Circulating Tumour DNA and Colorectal Cancer: the Next Revolutionary Biomarker?

PURPOSE OF REVIEW

Improving outcomes for patients with colorectal cancer in both the adjuvant and metastatic setting has been challenging. Here, we review the current and future directions for using ctDNA in clinical practice.

RECENT FINDINGS

Circulating tumour DNA (ctDNA) with its ability to detect minimal residual disease is beginning to refine the way we assess recurrence risk in the adjuvant setting. We can potentially tailor treatments to reduce recurrence risk and minimize treatment toxicity. In the metastatic setting, ctDNA can provide a less invasive method of detecting clinically important genetic changes to guide molecularly targeted treatment and to identify mechanisms of molecular resistance. ctDNA can be a surrogate marker for treatment response and help guide the timing of anti-EGFR rechallenge. We await the results of the randomized clinical trials assessing clinical utility of ctDNA in both the adjuvant and metastatic setting before incorporating ctDNA into clinical practice.

Gene Therapy Targeting p53 and KRAS for Colorectal Cancer Treatment: A Myth or the Way Forward?

Colorectal cancer (CRC) is the third most commonly diagnosed malignancy worldwide and is responsible as one of the main causes of mortality in both men and women. Despite massive efforts to raise public awareness on early screening and significant advancements in the treatment for CRC, the majority of cases are still being diagnosed at the advanced stage. This contributes to low survivability due to this cancer. CRC patients present various genetic changes and epigenetic modifications. The most common genetic alterations associated with CRC are p53 and KRAS mutations. Gene therapy targeting defect genes such as TP53 (tumor suppressor gene encodes for p53) and KRAS (oncogene) in CRC potentially serves as an alternative treatment avenue for the disease in addition to the standard therapy. For the last decade, significant developments have been seen in gene therapy for translational purposes in treating various cancers. This includes the development of vectors as delivery vehicles. Despite the optimism revolving around targeted gene therapy for cancer treatment, it also has various limitations, such as a lack of availability of related technology, high cost of the involved procedures, and ethical issues. This article will provide a review on the potentials and challenges of gene therapy targeting p53 and KRAS for the treatment of CRC.

Impact of Immunoscore on the Management of Stage II Colon Cancer Patients: A Physician Survey

Simple Summary

Selection of appropriate stage II colon cancer patients for adjuvant chemotherapy (AC) is controversial. A novel immune response classifier has previously been validated to refine patient selection, but its impact on oncologist treatment planning had yet to be described. In this survey, all but one oncologist altered clinical practice recommendations, and recommendations for AC prescriptions were reduced by half (among the Immunoscore-high cases (low recurrence risk)). This study revealed that the Immunoscore results could significantly decrease AC use in patients with stage II colon cancer who may not benefit from it, thereby reducing the administration of nonvalue care.

Abstract

Background: Adjuvant chemotherapy use in stage II colon cancer is controversial. Current prognostic risk factors do not take the tumor immune microenvironment into account. Consideration of the Immunoscore, which measures the host immune response at the tumor site, may assist clinicians in reducing adjuvant chemotherapy use in patients who are unlikely to benefit from it. This study sought to determine the potential clinical utility of the Immunoscore, via its effect on medical oncologists’ recommendations for management of patients with stage II colon cancer. Methods: De-identified vignettes of 10 patients with stage II colon cancer were presented to 25 practicing medical oncologists. Each participant completed surveys indicating recommendations for adjuvant chemotherapy and surveillance strategies. An educational session was subsequently conducted, and the same patient profiles were re-presented but included immunoscore results. Participants were again asked to provide their recommendations. A participant was counted as influenced if their responses were altered after immunoscore test results were provided. Results: All but one participant (96%) altered a management recommendation for ≥1 case. For individual cases, a mean of 55% (range, 40–80%) of participants altered their recommendations for adjuvant chemotherapy and/or surveillance. For the immunoscore-high cases (low-risk of recurrence), recommendations for adjuvant chemotherapy use decreased from 60% to 31%. Conclusions: These results indicate a willingness by oncologists to integrate immunoscore information into clinical practice recommendations. Incorporation of immunoscore data resulted in the reduction of nonvalue care in the simulated population. Confirmation in prospective studies is planned.

Cancer-associated fibroblasts impact the clinical outcome and treatment response in colorectal cancer via immune system modulation: a comprehensive genome-wide analysis

Background

Cancer-associated fibroblasts (CAFs) in the tumour microenvironment are associated with poor prognosis and chemoresistance in multiple solid tumours. However, there is a lack of universal measures of CAFs in colorectal cancer (CRC). The aim of this study was to assess the utility of a fibroblast-related gene signature (FRGS) for predicting patient outcomes and reveal its relevant mechanism.

Methods

The GSE39582 dataset, which includes 316 CRC patients who did not receive adjuvant chemotherapy was used as a discovery cohort to identify the prognostic fibroblast-related genes (FRGs). A total of 1352 CRC patients were divided into one training cohort (GSE39582, n = 461) and two validation cohorts (TCGA, n = 338; meta-validation, n = 553) for the construction of the FRGS and the verification of its prognostic value in stage II/III CRC patients. Functional annotation and analysis were performed to explore the underlying mechanism. The ability of the FRGS to predict immunotherapy response was further tested in a clear cell renal cell carcinoma (ccRCC) cohort.

Results

An 11-gene signature that had prognostic value for stage II/III CRC patients in both validation cohorts was developed (TCGA cohort: HR = 1.90, 95% CI 1.16–3.12, P < 0.01; meta-validation cohort: HR = 1.95, 95% CI 1.39–2.73, P < 0.001). A high level of CAFs was correlated with worse prognosis in CRC patients who did not receive adjuvant chemotherapy (HR = 3.63, 95% CI 2.24–5.88, P < 0.001). Importantly, patients in the low-risk group were found to be benefit from chemotherapy (P < 0.01), but not in the high CAF group (P > 0.05). Similar results were found in the TCGA cohort. Integrated with clinical characteristics, the FRGS was confirmed to be an independent prognostic factor in the multivariate analysis after adjustment for tumour TNM stage (GSE39582 cohort: HR = 3.19, 95% CI 1.88–5.41, P < 0.001; TCGA cohort: HR = 5.00, 95% CI 1.58–15.85, P = 0.007; meta-validation cohort: HR = 2.99, 95% CI 1.44–6.21, P = 0.003). Furthermore, the enrichment analysis found that the antitumour immune response was suppressed and the infiltration of CD4 T cells and M1 macrophages was depressed in the high CAF group. The FRGS was also found to have value in predicting for immunotherapy response in the ccRCC cohort.

Conclusions

The 11-gene FRGS had independent prognostic value for CRC patients, as well as utility in the prediction of benefit from chemotherapy. CAFs in the tumour microenvironment might have an impact on the prognosis of CRC patients via inhibiting immune response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10020-021-00402-3.

High-Risk Features Are Prognostic in dMMR/MSI-H Stage II Colon Cancer

BACKGROUND

High-risk features, such as T4 disease, bowel obstruction, poorly/undifferentiated histology, lymphovascular, perineural invasion, and <12 lymph nodes sampled, indicate poor prognosis and define high-risk stage II disease in proficient mismatch repair stage II colon cancer (CC). The prognostic role of high-risk features in dMMR/MSI-H stage II CC is unknown. Similarly, the role of adjuvant therapy in high-risk stage II CC with dMMR/MSI-H (≥1 high-risk feature) has not been studied in prospective trials. The aim of this analysis of the National Cancer Database is to evaluate the prognostic value of high-risk features in stage II dMMR/MSI-H CC.

METHODS

Univariate (UVA) and multivariate (MVA) Cox proportional hazards (Cox-PH) models were built to assess the association between clinical and demographic characteristics and overall survival. Kaplan-Meier survival curves were generated with log-rank tests to evaluate the association between adjuvant chemotherapy in high-risk and low-risk cohorts separately.

RESULTS

A total of 2,293 stage II CC patients have dMMR/MSI-H; of those, 29.5% (n = 676) had high-risk features. The high-risk dMMR/MSI-H patients had worse overall survival [5-year survival and 95%CI, 73.2% (67.3-78.1%) vs. 80.3% (76.7-83.5%), p = 0.0001]. In patients with stage II dMMR/MSI-H CC, the high-risk features were associated with shorter overall survival (OS) along with male sex, positive carcinoembryonic antigen, Charlson-Deyo score >1, and older age. Adjuvant chemotherapy administration was associated with better OS, regardless of the high-risk features in dMMR/MSI-H (log-rank test, p = 0.001) or not (p = 0.0006). When stratified by age, the benefit of chemotherapy was evident only in patients age ≥65 with high-risk features.

CONCLUSION

High-risk features are prognostic in the setting of dMMR/MSI-H stage II CC. Adjuvant chemotherapy may improve survival specifically in patients ≥65 years and with high-risk features.

Role of Circulating Tumor DNA in Gastrointestinal Cancers: Current Knowledge and Perspectives

Gastrointestinal (GI) cancers are major health burdens worldwide and biomarkers are needed to improve the management of these diseases along their evolution. Circulating tumor DNA (ctDNA) is a promising non-invasive blood and other bodily-fluid-based biomarker in cancer management that can help clinicians in various cases for the detection, diagnosis, prognosis, monitoring and personalization of treatment in digestive oncology. In addition to the well-studied prognostic role of ctDNA, the main real-world applications appear to be the assessment of minimal residual disease to further guide adjuvant therapy and predict relapse, but also the monitoring of clonal evolution to tailor treatments in metastatic setting. Other challenges such as predicting response to treatment including immune checkpoint inhibitors could also be among the potential applications of ctDNA. Although the level of advancement of ctDNA development in the different tumor localizations is still inhomogeneous, it might be now reliable enough to be soon used in clinical routine for colorectal cancers and shows promising results in other GI cancers.

KRAS and BRAF Mutations in Stage II/III Colon Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

KRAS and BRAF mutations are well-established predictive and prognostic factors in metastatic colorectal cancer, however their impact in the adjuvant setting has not yet been established.

METHODS

We performed a meta-analysis of adjuvant phase III trials in patients with stage II and III colon cancer with available data on the impact of KRAS/BRAF mutations on both disease-free survival (DFS) and overall survival (OS). Trials were subgrouped based on whether adjustment for microsatellite instability (MSI) was performed and the subgroup effect was analyzed through a meta-regression. To increase the precision of the estimates, a joint DFS/OS (so-called 'multivariate') meta-analysis was performed. All statistical tests were 2-sided.

RESULTS

Nine trials were selected (QUASAR 2, PETACC-8, N0147, CALGB-89803, NSABP-C07, NSABP-C08, PETACC-3, QUASAR, MOSAIC) including a total of 10893 patients. In the primary meta-analysis, KRAS mutation was associated with poor DFS (pooled HR = 1.36, 95% CI = 1.15-1.61, P < .001) and OS (pooled HR = 1.27, 95% CI = 1.03-1.55, P = .03) and BRAF mutation was also associated with poor DFS (pooled HR = 1.33, 95% CI = 1.00-1.78, P = .05) and OS (pooled HR = 1.49, 95% CI = 1.31-1.70, P < .001). MSI adjustment enhanced the effect of the mutations on outcome in the MSI-adjusted subgroup for both the KRAS mutation (pooled HR for DFS = 1.43, 95% CI = 1.15-1.79, P = .001; and pooled HR for OS = 1.33, 95% CI = 1.03-1.71, P = .03) and the BRAF mutation (pooled HR for DFS = 1.59, 95% CI = 1.22-2.07, P = .001; and pooled HR for OS = 1.67, 95% CI = 1.37-2.04, P < .001). The interaction between BRAF and MSI adjustment was statistically significant for DFS (P interaction = 0.02). This interaction was even more pronounced in the DFS/OS multivariate meta-analysis.

CONCLUSIONS

Both KRAS and BRAF mutations were statistically significantly associated with both DFS and OS, with the mutation effect being enhanced by MSI adjustment. Effective adjuvant treatment for microsatellite stable BRAF or KRAS-mutated colon cancer represents an unmet clinical need and exploring the use of recently available BRAF and KRAS inhibitors in this setting would be highly desirable.

Chimeric Ad5.F35 vector evades anti-adenovirus serotype 5 neutralization opposing GUCY2C-targeted antitumor immunity

BACKGROUND

Adenovirus serotype 5 (Ad5) is a commonly used viral vector for transient delivery of transgenes, primarily for vaccination against pathogen and tumor antigens. However, endemic infections with Ad5 produce virus-specific neutralizing antibodies (NAbs) that limit transgene delivery and constrain target-directed immunity following exposure to Ad5-based vaccines. Indeed, clinical trials have revealed the limitations that virus-specific NAbs impose on the efficacy of Ad5-based vaccines. In that context, the emerging focus on immunological approaches targeting cancer self-antigens or neoepitopes underscores the unmet therapeutic need for more efficacious vaccine vectors.

METHODS

Here, we evaluated the ability of a chimeric adenoviral vector (Ad5.F35) derived from the capsid of Ad5 and fiber of the rare adenovirus serotype 35 (Ad35) to induce immune responses to the tumor-associated antigen guanylyl cyclase C (GUCY2C).

RESULTS

In the absence of pre-existing immunity to Ad5, GUCY2C-specific T-cell responses and antitumor efficacy induced by Ad5.F35 were comparable to Ad5 in a mouse model of metastatic colorectal cancer. Furthermore, like Ad5, Ad5.F35 vector expressing GUCY2C was safe and produced no toxicity in tissues with, or without, GUCY2C expression. Importantly, this chimeric vector resisted neutralization in Ad5-immunized mice and by sera collected from patients with colorectal cancer naturally exposed to Ad5.

CONCLUSIONS

These data suggest that Ad5.F35-based vaccines targeting GUCY2C, or other tumor or pathogen antigens, may produce clinically relevant immune responses in more (≥90%) patients compared with Ad5-based vaccines (~50%).

The CIRCULATE Trial: Circulating Tumor DNA Based Decision for Adjuvant Treatment in Colon Cancer Stage II Evaluation (AIO-KRK-0217)

BACKGROUND

Guidance regarding adjuvant treatment decisions in stage II colorectal cancer (CRC) remains uncertain due to lack of predictive clinical or molecular markers. Recently, postoperative circulating tumour (ct)DNA has been demonstrated to be a strong prognostic marker in early colon cancer.

PATIENTS AND METHODS

CIRCULATE enrols patients with stage II microsatellite stable CRC in Germany (AIO) and Austria (ABCSG). Within the AIO, screening is supported by ColoPredict Plus 2.0, a molecular registry, and screening platform for interventional trials. Patient-specific mutations are centrally analysed by next generation sequencing in the resected primary tumour. A postoperative plasma sample is subsequently screened for the specific mutation(s). ctDNA positive (ctDNApos) patients are randomised (2:1) chemotherapy (capecitabine, oxaliplatin added an investigator's choice) or to follow-up (control group). ctDNA negative (ctDNAneg) patients are randomised (1:4) to be followed-up within CIRCULATE (control group) or outside the trial. Patients in the control group remain blinded to the ctDNA results. The primary objective is to compare disease free survival (DFS) of ctDNApos patients with chemotherapy or control. To demonstrate a treatment effect with a hazard ratio of 0.617 (3-year DFS rates 42.5% vs. 25%), 231 ctDNApos and estimated 2079 ctDNAneg patients are randomised. Secondary aims include to compare overall survival and DFS in the ctDNApos and ctDNAneg patient cohorts and ctDNA kinetics.

CONCLUSION

The CIRCULATE trial may establish ctDNA for adjuvant treatment decision in stage II colon cancer - and with the secondary objectives - support a ctDNA guided follow up in colon cancer stage II and beyond.

Reevaluating Disease-Free Survival as an Endpoint vs Overall Survival in Stage III Adjuvant Colon Cancer Trials

BACKGROUND

Disease-free survival (DFS) with a 3-year median follow-up (3-year DFS) was validated as a surrogate for overall survival (OS) with a 5-year median follow-up (5-year OS) in adjuvant chemotherapy colon cancer (CC) trials. Recent data show further improvements in OS and survival after recurrence in patients who received adjuvant FOLFOX. Hence, reevaluation of the association between DFS and OS and determination of the optimal follow-up duration of OS to aid its utility in future adjuvant trials are needed.

METHODS

Individual patient data from 9 randomized studies conducted between 1998 and 2009 were included; 3 trials tested biologics. Trial-level surrogacy examining the correlation of treatment effect estimates of 3-year DFS with 5 to 6.5-year OS was evaluated using both linear regression (RWLS2) and Copula bivariate (RCopula2) models and reported with 95% confidence intervals (CIs). For R2, a value closer to 1 indicates a stronger correlation.

RESULTS

Data from a total of 18 396 patients were analyzed (median age = 59 years; 54.0% male), with 54.1% having low-risk tumors (T1-3 and N1), 31.6% KRAS mutated, 12.3% BRAF mutated, and 12.4% microsatellite instability high or deficient mismatch repair tumors. Trial-level correlation between 3-year DFS and 5-year OS remained strong (RWLS2 = 0.82, 95% CI = 0.67 to 0.98; RCopula2 = 0.92, 95% CI = 0.83 to 1.00) and increased as the median follow-up of OS extended. Analyses limited to trials that tested biologics showed consistent results.

CONCLUSIONS

Three-year DFS remains a validated surrogate endpoint for 5-year OS in adjuvant CC trials. The correlation was likely strengthened with 6 years of follow-up for OS.

The Value of Sentinel Lymph Node Mapping for the Staging of Node-Negative Colon Cancer: Propensity Score and Mediation Analyses

Objectives

Mediation analysis to assess the protective impact of sentinel lymph node (SLN) mapping on prognosis and survival of patients with colon cancer through a more precise evaluation of the lymph node (LN) status.

Background

Up to 20% of patients with node-negative colon cancer develop disease recurrence. Conventional histopathological LN examination may be limited in describing the real metastatic burden of LN.

Methods

Data of 312 patients with stage I & II colon cancer was collected prospectively. Patients were either staged using intraoperative SLN mapping with multilevel sectioning and immunohistochemical staining of the SLN or conventional techniques. The value of the SLN mapping for the detection of truly node-negative patients was assessed using Cox regression and mediation analysis.

Results

SLN mapping was performed in 143 patients. Disease recurrence was observed in 13 (9.1%) patients staged with SLN mapping and in 27 (16%) staged conventionally. Five-year overall survival (OS) rate was 82.7% (95% confidence interval [CI], 76.5-89.4%) with SLN mapping compared with 65.8% (95% CI, 58.8-73.7%). Five-year cancer-specific survival (CSS) was 95.1% (95% CI, 91.3-99.0%) with SLN mapping compared with 92.5% (95% CI, 88.0-97.2%). Node-negative staging with SLN mapping was associated with significantly better OS (hazard ratio [HR], 0.64; 95% CI, 0.56-0.72; P < 0.001) and CSS (HR, 0.49; 95% CI, 0.39-0.61; P < 0.001) in multivariate analysis. Mediation analysis confirmed a direct protective effect of SLN mapping on OS (HR, 0.78; 95% CI, 0.52-0.96; P < 0.01) and disease-free survival (DFS) (HR, 0.75; 95% CI, 0.48-0.89; P < 0.01).

Conclusions

Staging performed by SLN mapping with multilevel sectioning provides more accurate results than conventional staging. The observed clinically relevant and statistically significant benefit in OS and DFS is explained by a more accurate detection of positive LN by SLN mapping.

Three Versus Six Months of Adjuvant Doublet Chemotherapy for Patients With Colorectal Cancer: A Multi-Country Cost-Effectiveness and Budget Impact Analysis

BACKGROUND

The Short Course Oncology Treatment (SCOT) trial demonstrated non-inferiority, less toxicity, and cost-effectiveness from a UK perspective of 3 versus 6 months of oxaliplatin-based chemotherapy for patients with colorectal cancer. This study assessed the cost-effectiveness of shorter treatment and the budget impact of implementing trial findings from the perspectives of all countries recruited to SCOT: Australia, Denmark, New Zealand, Spain, Sweden, and the United Kingdom.

PATIENTS AND METHODS

Individual cost-utility analyses were performed from the perspective of each country. Resource, quality of life, and survival estimates from the SCOT trial (N = 6065) were used. Probabilistic sensitivity analysis and subgroup analyses were undertaken. Using undiscounted costs from these cost-utility analyses, the impact on country-specific healthcare budgets of implementing the SCOT trial findings was calculated over a 5-year period. The currency used was US dollars (US$), and 2019 was the base year. One-way and scenario sensitivity analysis addressed uncertainty within the budget impact analysis.

RESULTS

Three months of treatment were cost saving and cost-effective compared to 6 months from the perspective of all countries. The incremental net monetary benefit per patient ranged from US$8972 (Spain) to US$13,884 (Denmark). The healthcare budget impact over 5 years for the base-case scenario ranged from US$3.6 million (New Zealand) to US$61.4 million (UK) and totaled over US$150 million across all countries.

CONCLUSION

This study has widened the transferability of results from the SCOT trial, showing that shorter treatment is cost-effective from a multi-country perspective. The vast savings from implementation could fully justify the investment in conducting the SCOT trial.

[Influence of molecular markers on oncological surgery of colorectal cancer]

Colorectal cancer (CRC) is still a very common disease and one of the best characterized malignancies on a molecular level. Interdisciplinary and multimodal treatment strategies should be preferred. In addition to surgical resection in localized stages as well as metastasectomy for oligometastatic advanced stages, neoadjuvant chemoradiotherapy for localized rectal cancer and cytostatic treatment, targeted treatment approaches should also be considered. This overview presents established and novel prognostic and predictive molecular markers of (metastasized) CRC and describes these as targeted therapy options. The determination of high microsatellite instability (MSI-H) has a therapeutic influence when planning adjuvant therapy and also now in the treatment of metastatic CRC. Furthermore, circulating tumor DNA represents a promising marker with respect to a recurrence in early as well as in advanced stages of disease. In addition to the RAS and BRAF mutation status and the localization of the primary tumor, an MSI‑H is also important with respect to the treatment strategy and should be determined before initiation of first-line treatment in metastasized CRC. New pharmaceutical approaches enable targeted interventions at the immunological or molecular level. The understanding of CRC as a heterogeneous disease has been increased using recently established analyses at the molecular level; however, it also generated many hypotheses that require further evaluation with respect to their clinical importance. Special attention is paid to patients affected by hereditary syndromes because of the early onset of disease and the considerable consequences individually and for the patient's family.

Treatment and Outcomes of Colorectal Cancer in Armenia: A Real-World Experience From a Developing Country

PURPOSE

In Armenia, colorectal cancer (CRC) is one of the most frequently diagnosed cancers. It is in the third place by incidence. The aim of this study was to evaluate treatment and outcomes of CRC in Armenia during the last 9 years.

MATERIALS AND METHODS

For this retrospective hospital-based study, we have collected data from two main oncology centers in Armenia: National Oncology Center and “Muratsan” Hospital of Yerevan State Medical University. The information about patients with CRC who were treated at these two centers between January 1, 2010 and July 1, 2018 was collected from the medical records. Log-rank test and Kaplan-Meier curves were used for survival analysis. Prognostic factors were identified by Cox regression.

RESULTS

A total of 602 patients with CRC were involved in the final analysis. Median follow-up time was 37 months (range, 3-207 months). A total of 8.6% of patients had stage I, 32.9% stage II, 38.0% stage III, and 17.6% stage IV cancer; for 2.7% patients, the stage was unknown. The main independent prognostic factors for overall survival (OS) were tumor stage, grade, and histology. Adjuvant chemotherapy has been shown to improve survival in stage II colon cancer and stage III rectal but not in stage II rectal cancer. Radiotherapy did not yield survival improvement in stage II or III rectal cancer. Three- and 5-year OS rates were 62.9% and 51.8% for all stages combined and 79.7% and 68.5% for stages I-II, 62.5% and 48.4% for stage III, and 24.4% and 17% for stage IV respectively.

CONCLUSION

As seen from our results, our survival rates are lower than those of the developed world. Additional research is needed to identify the underlying reasons and to improve patients’ treatment and outcomes in Armenia.

Detection of Circulating Tumor Cells and Microbial DNA Fragments in Stage III Colorectal Cancer Patients under Three versus Six Months of Adjuvant Treatment

Oxaliplatin-fluoropyrimidine combination therapy is the gold standard treatment for patients with stage III colorectal cancer (CRC); however, treatment duration is now under re-evaluation. The aim of the study was the evaluation of the non-inferiority of three over six months treatment with FOLFOX or CAPOX, in stage III CRC patients. Peripheral blood samples from 121 patients were collected, at three time points during treatment and evaluated for circulating tumor cells (CTCs) and microbial DNA detection (16S rRNA, Escherichia coli, Bacteroides fragilis, Candida albicans). Of all patients, 41.3% and 58.7% were treated with FOLFOX and CAPOX, respectively. CTCs were significantly decreased and increased after three and six months of treatment, respectively. CAPOX tends to reduce the CTCs after 3 months, whereas there is a statistically significant increase of CTCs in patients under FOLFOX after 6 months. A significant correlation was demonstrated between microbial DNA detection and both CTCs detection at baseline and CTCs increase between baseline and three months of treatment. To conclude, the current study provides additional evidence of non-inferiority of three over 6 months of treatment, mainly in patients under CAPOX.

Adjuvant Therapies in Colon Cancer

Most of the patients with localized colon cancer undergo curative resection. However, significant number of patients will recur with metastatic disease, especially those with node positive cancer. Adjuvant chemotherapy has shown to improve cure rate and survival by eradicating micrometastases. The benefit of adjuvant therapy is well established in node-positive cancers, while their role in stage II cancer is not well defined. A number of molecular markers have been identified that are prognostic and/or predictive in colon cancer. Such molecular markers, and other clinicopathological features play an important role in selection of appropriate therapy and duration of treatment. Emerging evidence for the utility of genomic profiling or detection of circulating tumor DNA (ctDNA) are promising which may further facilitate decision making in the future. This chapter reviews the evolution of adjuvant therapy for resected colon cancer, the current evidence and the factors influence the choice of therapy.

The platelet to lymphocyte ratio is a potential inflammatory marker predicting the effects of adjuvant chemotherapy in patients with stage II colorectal cancer

Background

The effects of adjuvant chemotherapy in patients with stage II colorectal cancer (CRC) has been in controversy for a long time. Our study aimed to find an effective inflammatory marker to predict the effects of chemotherapy.

Methods

Seven hundred eight stage II CRC patients in our institution were included. The subpopulation treatment effect pattern plot (STEPP) analysis was used to determine the optimal inflammatory marker and cut-off value. Propensity score matching (PSM) was performed to balance discrepancy between the chemotherapy and non-chemotherapy group. Survival analyses based on overall survival (OS) and cancer-specific survival (CSS) were performed with Kaplan-Meier methods with log-rank test and Cox proportional hazards regression. The restricted mean survival time (RMST) was used to measure treatment effect.

Results

The platelet to lymphocyte ratio (PLR) was chosen as the optimal marker with a cut-off value of 130 according to STEPP. In OS analysis, PLR was significantly associated with the effects of chemotherapy (interaction p = 0.027). In the low-PLR subgroup, the chemotherapy patients did not have a longer OS than the non-chemotherapy patients (HR: 0.983, 95% CI: 0.528–1.829). In the high-PLR subgroup, the chemotherapy patients had a significantly longer OS than the non-chemotherapy patients (HR: 0.371, 95% CI: 0.212–0.649). After PSM, PLR was still associated with the effects of chemotherapy. In CSS analysis, PLR was not significantly associated with the effects of chemotherapy (interaction p = 0.116). In the low-PLR subgroup, the chemotherapy patients did not have a longer CSS than the non-chemotherapy patients (HR: 1.016, 95% CI: 0.494–2.087). In the high-PLR subgroup, the chemotherapy patients had a longer CSS than the non-chemotherapy patients (HR: 0.371, 95% CI: 0.212–0.649). After PSM, PLR was not associated with the effects of chemotherapy.

Conclusions

PLR is an effective marker to predict the effects of chemotherapy in patients with stage II CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08521-0.