Current and emerging anti-angiogenic therapies in gastrointestinal and hepatobiliary cancers

Gastrointestinal tumours are a heterogeneous group of neoplasms that arise in the gastrointestinal tract and hepatobiliary system. Their incidence is rising globally and they currently represent the leading cause of cancer-related mortality worldwide. Anti-angiogenic agents have been incorporated into the treatment armamentarium of most of these malignancies and have improved survival outcomes, most notably in colorectal cancer and hepatocellular carcinoma. New treatment combinations with immunotherapies and other agents have led to unprecedented benefits and are revolutionising patient care. In this review, we detail the mechanisms of action of anti-angiogenic agents and the preclinical rationale underlying their combinations with immunotherapies. We review the clinical evidence supporting their use across all gastrointestinal tumours, with a particular emphasis on colorectal cancer and hepatocellular carcinoma. We discuss available biomarkers of response to these therapies and their utility in routine clinical practice. Finally, we summarise ongoing clinical trials in distinct settings and highlight the preclinical rationale supporting novel combinations.

Clinical Observation of Fuzheng Xiaoji Granule in the Treatment of Stage IIIC Colorectal Cancer

Objective. This study aimed to evaluate the effectiveness and safety of Fuzheng Xiaoji granule in patients with stage IIIC colorectal cancer. Methods. A total of 150 patients with stage IIIC colorectal cancer treated in Shanghai Ruijin Hospital from January 2019 to January 2022 were selected. They were divided into treatment and control groups according to a 2 : 1 random number table. There were 100 cases in the treatment group and 50 cases in the control group. The treatment group was administered Fuzheng Xiaoji (FZXJ) granule, and the control group was administered the placebo orally. The primary endpoint was disease-free survival (DFS). In addition, after 6 months, the changes in Traditional Chinese Medicine (TCM) symptom score (fatigue, emotional depression, chest tightness, insomnia, anorexia, abdominal distension, abdominal pain, soreness and weakness in the waist and legs, chills, and dysphoria in the chest, palm, and soles) were compared. Results. The DFS was 34.37 ± 2.91 months in the control group and 37.0 ± 1.08 months in the treatment group ( $p<0.05$ ). Compared with the control group, the treatment group showed less fatigue, abdominal distension, and soreness and weakness in the waist and legs ( $p<0.05$ ), significantly. The scores of emotional depression and anorexia decreased obviously, with a significant difference between the control and treatment groups ( $p<0.01$ ). There were no significant differences between the control and treatment groups in the incidence of chest tightness, insomnia, abdominal pain, chills, and dysphoria in the chest, palm, and soles ( $p>0.05$ ). Conclusion. Fuzheng Xiaoji granule can improve patients’ symptoms and prolong the DFS.

Simultaneous Imaging and Therapy Using Epitope-Specific Anti-Epidermal Growth Factor Receptor (EGFR) Antibody Conjugates

Matuzumab and nimotuzumab are anti-EGFR monoclonal antibodies that bind to different epitopes of domain III of EGFR. We developed ⁸⁹Zr-matuzumab as a PET probe for diagnosis/monitoring of response to treatment of a noncompeting anti-EGFR nimotuzumab antibody drug conjugate (ADC) using mouse colorectal cancer (CRC) xenografts. We developed ⁸⁹Zr-matuzumab and performed quality control in EGFR-positive DLD-1 cells. The K_D of matuzumab, DFO-matuzumab and ⁸⁹Zr-matuzumab in DLD-1 cells was 5.9, 6.2 and 3 nM, respectively. A competitive radioligand binding assay showed that ⁸⁹Zr-matuzumab and nimotuzumab bound to noncompeting epitopes of EGFR. MicroPET/CT imaging and biodistribution of ⁸⁹Zr-matuzumab in mice bearing EGFR-positive xenografts (HT29, DLD-1 and MDA-MB-231) showed high uptake that was blocked with pre-dosing with matuzumab but not with the noncompeting binder nimotuzumab. We evaluated nimotuzumab-PEG₆-DM1 ADC in CRC cells. IC₅₀ of nimotuzumab-PEG₆-DM1 in SNU-C2B, DLD-1 and SW620 cells was dependent on EGFR density and was up to five-fold lower than that of naked nimotuzumab. Mice bearing the SNU-C2B xenograft were treated using three 15 mg/kg doses of nimotuzumab-PEG₆-DM1, and ⁸⁹Zr-matuzumab microPET/CT was used to monitor the response to treatment. Treatment resulted in complete remission of the SNU-C2B tumor in 2/3 mice. Matuzumab and nimotuzumab are noncompeting and can be used simultaneously.

BRAF Mutations in Colorectal Liver Metastases: Prognostic Implications and Potential Therapeutic Strategies

Simple Summary

In this literature review, we investigated the relationship between BRAF mutation and prognosis in patients with colorectal cancer liver metastases. We also investigated factors affecting the prognosis of patients with BRAF mutations and summarized the latest research on targeted therapies.

Abstract

Surgery combined with chemotherapy and precision medicine is the only potential treatment for patients with colorectal cancer liver metastases (CRLM). The use of modern molecular biotechnology to identify suitable biomarkers is of great significance for predicting prognosis and formulating individualized treatment plans for these patients. BRAF mutations, particularly V600E, are widely believed to be associated with poor prognosis in patients with metastatic CRC (mCRC). However, it is unclear which specific factors affect the prognosis of CRLM patients with BRAF mutations. It is also unknown whether patients with resectable CRLM and BRAF mutations should undergo surgical treatment since there is an increased recurrence rate after surgery in these patients. In this review, we combined the molecular mechanism and clinical characteristics of BRAF mutations to explore the prognostic significance and potential targeted therapy strategies for patients with BRAF-mutated CRLM.

BRAF-Mutated Advanced Colorectal Cancer: A Rapidly Changing Therapeutic Landscape

BRAF-mutated advanced colorectal cancer is a relatively small but critical subset of this tumor type on the basis of prognostic and predictive implications. BRAF alterations in colorectal cancer are classified into three functional categories on the basis of signaling mechanisms, with the class I BRAFV600E mutation occurring most frequently in colorectal cancer. Functional categorization of BRAF mutations in colorectal cancer demonstrates distinct mitogen-activated protein kinase pathway signaling. On the basis of recent clinical trials, current standard-of-care therapies for patients with BRAFV600E-mutated metastatic colorectal cancer include first-line cytotoxic chemotherapy plus bevacizumab and subsequent therapy with the BRAF inhibitor encorafenib and antiepidermal growth factor receptor antibody cetuximab. Treatment regimens currently under exploration in BRAFV600E-mutant metastatic colorectal cancer include combinatorial options of various pathway-targeted therapies, cytotoxic chemotherapy, and/or immune checkpoint blockade, among others. Circumvention of adaptive and acquired resistance to BRAF-targeted therapies is a significant challenge to be overcome in BRAF-mutated advanced colorectal cancer.

Perioperative Chemotherapy for Liver Metastasis of Colorectal Cancer: Lessons Learned and Future Perspectives

OPINION STATEMENT

Colorectal cancer (CRC) is a major public health problem and the 2nd leading-cause of cancer-related death worldwide. Around 30% of patients present with metastatic disease and 50% of those with early disease will eventually relapse. The metastatic spread occurs mainly to the liver, which is the exclusive site in 30-40% of the cases. Surgery is the main curative option for liver recurrence, but only one out of five patients are eligible for resection. Moreover, even if surgery is feasible, recurrence rate is high, occurring in up to 75% of patients. Therefore, additional treatment to improve these disappointing outcomes has been sought. Adjuvant and perioperative chemotherapy aim to eradicate early micrometastatic disease, decreasing recurrence rates, and improving survival outcomes. Different chemotherapy regimens, mainly extrapolated from the adjuvant experience, have showed conflicting results, with improvements in disease free but not in overall survival. The addition of targeted therapies to chemotherapy has improved response rates and resectability when administered preoperatively, but did not have an impact on survival in the adjuvant setting. There is a need to critically synthetize the available evidence on perioperative and conversion therapy from the past years, and appraise areas of current research and potential future directions.

High Expression of CUL9 Is Prognostic and Predictive for Adjuvant Chemotherapy in High-Risk Stage II and Stage III Colon Cancer

We evaluated the clinical implications of CUL9 expression on the prognosis and the predictive value for adjuvant chemotherapy in colon cancer. A total of 1078 consecutive patients treated with radical resection from 2008 to 2012 were included. Formalin-fixed, paraffin-embedded specimens were used as immunohistochemistry (IHC) for CUL9. For all patients, high expression of CUL9 was identified as an independent prognostic factor for overall survival (HR = 1.613, 95% CI 1.305−1.993, p < 0.001) and disease-free survival (HR = 1.570, 95% CI 1.159−2.128, p = 0.004). The prognostic value of high CUL9 expression was confirmed in an independent validation cohort from the GEO database. The efficacy of adjuvant chemotherapy was analyzed among patients with high-risk stage II and stage III disease. Those with high CUL9 expression from the full dose group had better disease-free survival (HR = 0.477, 95% CI 0.276−0.825, p = 0.006) than those from the reduced dose group. The interaction test between CUL9 expression and the treatment reached significance and was not confounded by T stage, N stage and histopathological grade. In general, high expression of CUL9 was an independent prognostic factor in patients with colon cancer. In those with high-risk stage II and stage III disease, high expression of CUL9 was associated with the benefit from standard 6-months adjuvant chemotherapy regimens.

Real-World Assessment of Cancer Drugs Using Local Data Uploaded to the Systemic Anti-Cancer Therapy Dataset in England

AIMS

In England, not all cancer drugs are routinely funded; new medicines are first appraised by the National Institute for Health and Care Excellence. Funding can be temporarily given through the Cancer Drugs Fund while further information is collected. The Systemic Anti-Cancer Therapy (SACT) dataset collects information on all patients receiving chemotherapy in England. To date, little has been published, despite concerns that real-world effectiveness of medicines may be inferior to that seen in clinical trials. The aim of the present study was to establish the feasibility of using our local copy of routinely collected SACT data for the evaluation of outcomes, using the data within the context of gastrointestinal cancers.

MATERIALS AND METHODS

We used our local SACT dataset submissions from three National Health Service trusts, with a reproducible method of data linkage, to undertake a cohort analysis of treatment duration and overall survival for cetuximab, panitumumab, trifluridine/tipiracil (all three in colorectal cancer), sorafenib (in hepatocellular cancer) and nab-paclitaxel (nanoparticle albumin-bound paclitaxel) with gemcitabine (in pancreatic cancer) for all patients treated from May 2016 to March 2021.

RESULTS

In our population, epidermal growth factor receptor inhibitors and trifluridine/tipiracil and sorafenib performed similarly to expected but nab-paclitaxel with gemcitabine in pancreatic cancer seemed to be no better than gemcitabine alone, when given within the current funding arrangements in England.

CONCLUSIONS

Our results support the publication of national outcome data. If these results are confirmed on a larger cohort, it would support the reappraisal of certain drugs and provide further evidence to clinicians and patients when deciding the best treatment.

Biologics in rectal cancer

INTRODUCTION

Despite the use of multimodality therapy, locally advanced rectal cancer (LARC) still presents high rates of disease recurrence. Fluoropyrimidine-based chemotherapy concurrently with radiation therapy (RT) remains the cornerstone of neoadjuvant therapy of LARC, and novel therapies are urgently needed in order to improve the clinical outcomes.

AREAS COVERED

We aim to summarize data from completed and ongoing clinical trials addressing the role of biological therapies, including monoclonal antibodies, immune checkpoint inhibitors (ICIs), antibody-drug conjugates, bispecific antibodies, and gene therapies in the systemic therapy of rectal cancer.

EXPERT OPINION

Deeper understanding of the molecular biology of colorectal cancer (CRC) has allowed meaningful advances in the systemic therapy of metastatic disease in the past few years. The larger applicability of biological therapy in CRC, including genome-guided targeted therapy, antiangiogenics, and immunotherapy, gives us optimism for the personalized management of rectal cancer. Microsatellite instability (MSI) tumors have demonstrated high sensitivity to ICIs, and preliminary findings in the neoadjuvant setting of rectal cancer are promising. To date, antiangiogenic and anti-EGFR therapies in LARC have not demonstrated the same benefit seen in metastatic disease. The outstanding results accomplished by biomarker-guided therapy in metastatic CRC will guide future developments of biological therapy in LARC.

Encorafenib plus cetuximab for the treatment of BRAF-V600E-mutated metastatic colorectal cancer

B-type RAF (BRAF)-V600E mutations in metastatic colorectal cancer (mCRC) have been described in up to 12% of the patients. This mutation confers a bad prognostic and poor response with standard chemotherapy. Unlike the scenario for BRAF mutant melanoma, successful BRAF blockade in mCRC has emerged as a complex path, primarily due to the complex underlying biology of mCRC. The BEACON trial has reshaped the therapeutic landscape of BRAF mCRC demonstrating the benefit of the BRAF inhibitor encorafenib in combination with the anti-epidermal growth factor receptor cetuximab. This paper aims to review the main features of BRAF mCRC as well as to review the development of targeted therapy and biomarkers in this specific population. Finally, a deep insight into the underlying biology and molecular classification of BRAF-V600E mCRC has also been performed. The words 'BRAF-V600E mutation', 'colorectal cancer', 'BRAF inhibitors', 'consensus molecular subtypes', 'encorafenib', and 'cetuximab' were used to identify the clinical trials from phase I to phase III related to the development of BRAF inhibitors in this population. A deep search among international meetings (American Society of Clinical Oncology and European Society of Medical Oncology) has been performed to incorporate the last trials presented. BRAF-V600E mCRC is a challenging disease, mostly because of its molecular biology. The BEACON trial has been the most important therapeutic change in the last decade. Nevertheless, new information regarding biomarkers or novel combinations including BRAF inhibitors plus immune checkpoint inhibitors are also promising.

Impact of early tumor shrinkage on quality of life in patients treated with first-line cetuximab plus chemotherapy for unresectable metastatic colorectal cancer: results of Phase II QUACK trial

PURPOSE

Although early tumor shrinkage (ETS) is a predictor of improved overall survival (OS), the association between ETS and health-related quality of life (HRQOL) remains unclear for patients with metastatic colorectal cancer (mCRC) treated with first-line cetuximab plus chemotherapy.

METHODS

The data were collected from a prospective trial that assessed HRQOL using the EORTC QLQ-C30. The impact of ETS on HRQOL was estimated using a linear mixed-effects model for repeated measures.

RESULTS

ETS was achieved in 82 (64.1%) of 128 mCRC patients treated with first-line cetuximab plus chemotherapy, and these patients had a significantly longer OS than those without ETS (HR, 0.38; 95% CI, 0.20-0.72; P = .002). Asymptomatic patients with ETS had a favorable OS, while symptomatic patients without ETS had a worse OS (2-year OS rates, 77.8% vs. 42.5%). Symptomatic patients with ETS had similar outcomes as asymptomatic patients without ETS (2-year OS rates, 64.1% vs. 67.0%). For symptomatic patients, ETS was associated with improved HRQOL scores between baseline and 8 weeks: the mean changes for patients with and without ETS were 5.86 and -4.94 for global health status (GHS)/QOL, 26.73 and 3.79 for physical functioning, and 13.58 and -3.10 for social functioning, respectively. The improved HRQOL was comparable to that of asymptomatic patients without ETS. For asymptomatic patients, ETS showed a decreased deterioration in HRQOL.

CONCLUSION

Our findings highlight the importance of ETS for HRQOL and prognostic estimates, and assessing ETS may provide clinically useful information for physicians and patients to make more informed decisions.

Gene Mutational Clusters in the Tumors of Colorectal Cancer Patients With a Family History of Cancer

Introduction

Family history is a high-risk factor for colorectal cancer (CRC). The risk comes not only from known germline mutations but also from the other family-related mechanisms. Uncovering them would be an important step to improve the diagnosis and treatment of these patients.

Method

Samples from 168 patients with advanced CRC were collected and applied to next-generation sequencing of 624 pan-cancer genes. Genomic mutations and significantly mutated genes were identified. Significantly mutated genes and co-mutated genes were used to cluster patients. For each cluster of patients, mutational signatures were extracted. The identified mutational signatures were further validated in the other independent cohort.

Result

Significantly mutated genes including TP53, APC, KRAS, and SMAD4 were found associated with tumor mutational burden and microsatellite instability. LRP1, ACVR2A, and SETBP1 were found co-mutated. Patients with mutations in LRP1, ACVR2A, and SETBP1 tend to have a family history of cancer. Those patients tended to have right-sided tumors with high tumor mutational burden and microsatellite instability. Among them, signature analysis identified two possible etiologies, SBS10a (defective polymerase epsilon exonuclease domain) and SBS6 (defective DNA mismatch repair and microsatellite unstable tumors). These signatures were also found in another independent cohort.

Conclusion

The gene cluster (LRP1, ACVR2A, and SETBP1) could be a good biomarker of these patients with a family risk, which was characterized by right-sidedness, high tumor mutational burden, and high microsatellite instability.

Cross-Resistance Among Sequential Cancer Therapeutics: An Emerging Issue

Over the past two decades, cancer treatment has benefited from having a significant increase in the number of targeted drugs approved by the United States Food and Drug Administration. With the introduction of targeted therapy, a great shift towards a new era has taken place that is characterized by reduced cytotoxicity and improved clinical outcomes compared to traditional chemotherapeutic drugs. At present, targeted therapies and other systemic anti-cancer therapies available (immunotherapy, cytotoxic, endocrine therapies and others) are used alone or in combination in different settings (neoadjuvant, adjuvant, and metastatic). As a result, it is not uncommon for patients affected by an advanced malignancy to receive subsequent anti-cancer therapies. In this challenging complexity of cancer treatment, the clinical pathways of real-life patients are often not as direct as predicted by standard guidelines and clinical trials, and cross-resistance among sequential anti-cancer therapies represents an emerging issue. In this review, we summarize the main cross-resistance events described in the diverse tumor types and provide insight into the molecular mechanisms involved in this process. We also discuss the current challenges and provide perspectives for the research and development of strategies to overcome cross-resistance and proceed towards a personalized approach.

Drug Resistance in Colorectal Cancer: From Mechanism to Clinic

Colorectal cancer (CRC) is one of the leading causes of death worldwide. The 5-year survival rate is 90% for patients with early CRC, 70% for patients with locally advanced CRC, and 15% for patients with metastatic CRC (mCRC). In fact, most CRC patients are at an advanced stage at the time of diagnosis. Although chemotherapy, molecularly targeted therapy and immunotherapy have significantly improved patient survival, some patients are initially insensitive to these drugs or initially sensitive but quickly become insensitive, and the emergence of such primary and secondary drug resistance is a significant clinical challenge. The most direct cause of resistance is the aberrant anti-tumor drug metabolism, transportation or target. With more in-depth research, it is found that cell death pathways, carcinogenic signals, compensation feedback loop signal pathways and tumor immune microenvironment also play essential roles in the drug resistance mechanism. Here, we assess the current major mechanisms of CRC resistance and describe potential therapeutic interventions.

Patient-Derived Organoid Model in the Prediction of Chemotherapeutic Drug Response in Colorectal Cancer

As an emerging technology in precision medicine, the patient-derived organoid (PDO) technology has been indicated to provide novel modalities to judge the sensitivity of individual tumors to cancer drugs. In this work, an in vitro model of colorectal cancer (CRC) was established using the PDO culture, and it is demonstrated that the PDO samples preserved, to a great extent, the histologic features and marker expression of the original tumor tissues. Subsequently, cancer drugs 5-FU, oxaliplatin, and irinotecan were selected and screened on five CRC PDO samples, while the patient-derived organoid xenograft (PDOX) model was applied for comparison. The receiver operating characteristic (ROC) curve was drawn according to the IC₅₀ data from the PDO model and the relative tumor proliferation rate (T/C%) from PDOX. Interestingly, the area under the ROC curve was 0.84 (95% CI, 0.64-1.04, P value = 0.028), which suggested that the IC₅₀ of cancer drugs from the PDO model was strongly correlated with PDOX responses. In addition, the optimal sensitivity cutoff value for drug screening in CRC PDOs was identified at 10.35 μM, which could act as a reference value for efficacy evaluation of 5-FU, oxaliplatin, and irinotecan in the colorectal cancer drug screening. Since there are no unified criteria to judge the sensitivity of drugs in vitro, our work provides a method for establishing in vitro evaluation criteria via PDO and PDOX model using the patient tissues received from local hospitals, exhibiting potential in clinical cancer therapy and precision medicine.

Effect of KRAS mutations and p53 expression on the postoperative prognosis of patients with colorectal cancer

Background

In the occurrence and development of colorectal cancer, p53 is an important regulator downstream of the MAPK signaling pathway and plays an important role in inhibiting abnormal proliferation signals generated by KRAS mutations. The purpose of this study is to explore the correlation between KRAS mutations and p53 expression and evaluate their prognosis values in colorectal cancer.

Methods

PCR technology and immunohistochemical (IHC) staining were used to detect KRAS mutation status and p53 expression level in 266 specimens of colorectal adenocarcinoma. Based on p53 expression level, these were divided into high expression and normal groups. Patients with KRAS mutations were divided into mutant and wild‐type groups. The two were combined with each other to analyze the relationship between patients' clinical data and their impact on the prognosis.

Results

KRAS mutations were found in 38.6% of the patients and 40.8% had a high p53 expression. There was no significant difference in the overall survival rate of patients, with or without KRAS gene mutations, and p53 expression level. In the group of patients with KRAS mutations, the survival time of patients with a high p53 expression was significantly lower than that of patients with a normal p53 expression (p = 0.020, log‐rank test). Multivariate analysis showed that p53 high expression is an independent risk factor for the overall survival time of patients with KRAS mutations (HR = 2.330, 95% CI = 1.041–5.216, p < 0.05).

Conclusion

Colorectal cancer patients with KRAS mutations with a high p53 expression have a poor prognosis.

Microsatellite and RAS/RAF Mutational Status as Prognostic Factors in Colorectal Peritoneal Metastases Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) leads to prolonged survival for selected patients with colorectal (CRC) peritoneal metastases (PM). This study aimed to analyze the prognostic role of micro-satellite (MS) status and RAS/RAF mutations for patients treated with CRS.

METHODS

Data were collected from 13 Italian centers with PM expertise within a collaborative group of the Italian Society of Surgical Oncology. Clinical and pathologic variables and KRAS/NRAS/BRAF mutational and MS status were correlated with overall survival (OS) and disease-free survival (DFS).

RESULTS

The study enrolled 437 patients treated with CRS-HIPEC. The median OS was 42.3 months [95% confidence interval (CI), 33.4-51.2 months], and the median DFS was 13.6 months (95% CI, 12.3-14.9 months). The local (peritoneal) DFS was 20.5 months (95% CI, 16.4-24.6 months). In addition to the known clinical factors, KRAS mutations (p = 0.005), BRAF mutations (p = 0.01), and MS status (p = 0.04) were related to survival. The KRAS- and BRAF-mutated patients had a shorter survival than the wild-type (WT) patients (5-year OS, 29.4% and 26.8% vs 51.5%, respectively). The patients with micro-satellite instability (MSI) had a longer survival than the patients with micro-satellite stability (MSS) (5-year OS, 58.3% vs 36.7%). The MSI/WT patients had the best prognosis. The MSS/WT and MSI/mutated patients had similar survivals, whereas the MSS/mutated patients showed the worst prognosis (5-year OS, 70.6%, 48.1%, 23.4%; p = 0.0001). In the multivariable analysis, OS was related to the Peritoneal Cancer Index [hazard ratio (HR), 1.05 per point], completeness of cytoreduction (CC) score (HR, 2.8), N status (HR, 1.6), signet-ring (HR, 2.4), MSI/WT (HR, 0.5), and MSS/WT-MSI/mutation (HR, 0.4). Similar results were obtained for DFS.

CONCLUSION

For patients affected by CRC-PM who are eligible for CRS, clinical and pathologic criteria need to be integrated with molecular features (KRAS/BRAF mutation). Micro-satellite status should be strongly considered because MSI confers a survival advantage over MSS, even for mutated patients.

Immunopeptidomic analyses of colorectal cancers with and without microsatellite instability

Colorectal cancer is the second leading cause of cancer death worldwide, and the incidence of this disease is expected to increase as global socioeconomic changes occur. Immune checkpoint inhibition therapy is effective in treating a minority of colorectal cancer tumors; however, microsatellite stable tumors do not respond well to this treatment. Emerging cancer immunotherapeutic strategies aim to activate a cytotoxic T cell response against tumor-specific antigens, presented exclusively at the cell surface of cancer cells. These antigens are rare and are most effectively identified with a mass spectrometry-based approach, which allows the direct sampling and sequencing of these peptides. Although the few tumor-specific antigens identified to date are derived from coding regions of the genome, recent findings indicate that a large proportion of tumor-specific antigens originate from allegedly noncoding regions. Here, we employed a novel proteogenomic approach to identify tumor antigens in a collection of colorectal cancer-derived cell lines and biopsy samples consisting of matched tumor and normal adjacent tissue. The generation of personalized cancer databases paired with mass spectrometry analyses permitted the identification of more than 30,000 unique MHC I-associated peptides. We identified 19 tumor-specific antigens in both microsatellite stable and unstable tumors, over two-thirds of which were derived from noncoding regions. Many of these peptides were derived from source genes known to be involved in colorectal cancer progression, suggesting that antigens from these genes could have therapeutic potential in a wide range of tumors. These findings could benefit the development of T cell-based vaccines, in which T cells are primed against these antigens to target and eradicate tumors. Such a vaccine could be used in tandem with existing immune checkpoint inhibition therapies, to bridge the gap in treatment efficacy across subtypes of colorectal cancer with varying prognoses. Data are available via ProteomeXchange with identifier PXD028309.

More Liver Metastases Detected Intraoperatively Indicates Worse Prognosis for Colorectal Liver Metastases Patients after Resection Combined with Microwave Ablation

Background

Whether more tumor numbers detected in surgery compared to preoperative image affecting survival of colorectal liver metastases (CRLM) patients after hepatectomy combined with microwave ablation (MWA) remains unclear.

Methods

From 2013 to 2018, 85 CRLM patients who underwent hepatectomy combined with MWA were retrospectively assessed. Compared to the tumor numbers in preoperative image, patients with equal intraoperative tumor numbers were defined as the equal number group (n = 45); patients detected more tumor numbers in surgery were defined as the more number group (n = 40). Clinicopathological factors and prognosis were compared between two groups.

Results

Compared to the equal number group, the more number group was characterized by more lymphatic metastasis, synchronous metastasis of liver lesion, and tumor numbers over 5 (all P < 0.05). Median survival time was 46.7 months and 26.8 months in the equal and more number group. Significantly worse overall survival (OS) was found in more number group to the equal number group (P = 0.027). In Cox analysis, more tumor number than image and high level of carbohydrate antigen 19-9 (CA19-9) were poor prognostic factors for OS.

Conclusion

In patients receiving hepatectomy combined with MWA, detecting more liver metastases in surgery than preoperative image indicates poor long-term survival. These patients were characterized by more lymphatic metastasis, synchronous metastasis of liver lesion, and tumor numbers over 5. Intensive follow-up to detect early recurrence and potent postoperative therapy to improve survival may be justified in patients detected more tumor numbers in surgery with a high CA19-9 level.

BRAF-mutated colorectal adenocarcinomas: Pathological heterogeneity and clinical implications

Advances in molecular biology have markedly increased our understanding of the heterogeneous molecular landscape of colorectal cancer (CRC). Up to 15% of CRCs harbor the BRAF p.V600E somatic mutation (BRAFmt), a well-established negative prognostic marker in patients with metastatic CRC (mCRC). The BEACON CRC trial set a new standard of care in patients with progressive BRAFmt cancers, consisting of the combination of encorafenib and cetuximab. On these bases, BRAF mutational testing is now recommended in patients with mCRC. However, efforts are needed to further stratify patients carrying this mutation. Here, we discuss the heterogeneous pathologic and molecular landscape of BRAFmt CRCs, focusing on the promises and pitfalls of molecular diagnostics, on novel biomarkers to improve patients' stratification and on the current diagnostic scenario for CRC. We believe that a better stratification based on histopathological features and novel molecular biomarkers should be performed to optimize patient management and therapeutic decision-making.

Patient demographics and management landscape of metastatic colorectal cancer in the third-line setting: Real-world data in an australian population

BACKGROUND

Colorectal cancer is the third most common cancer and second leading cause of cancer mortality in Australia, thus carrying a significant disease burden.

AIMS

This analysis aims to explore real-world treatment landscape of metastatic colorectal cancer in the third-line setting.

METHODS

We retrospectively analysed treatment of recurrent and advanced colorectal cancer (TRACC) registry database from 2009 onwards. Patients treated with palliative intent who progressed after two lines of therapies were included. One treatment line was defined as any combination of systemic therapy given until progression.

RESULTS

Out of 1820 patients treated palliatively, 32% (590 patients) met study criteria. Of these, 43% (254 patients) proceeded to third-line therapy, equating to 14% of all metastatic patients. In KRAS mutant or unknown tumours (97 patients), fluoropyrimidine (FP)-oxaliplatin combination was the most common choice (51%), followed by FP-irinotecan (15%), trifluridine/tipiracil (11%), mono-chemotherapy (10%), regorafenib (5%) and others (7%). Majority of FP-doublet (83%) was given as rechallenge. In 157 patients with KRAS wildtype disease, monotherapy with EGFR inhibitor was most commonly used (41%), followed by EGFR inhibitor with chemotherapy (20%), FP-doublet (18%), mono-chemotherapy (6%), trifluridine/tipiracil (6%), regorafenib (1%) and others (8%). Median overall survival was 7.1 months (range 0.4-41.2), and median time on third-line treatment was 3 months (range 0.1-40).

CONCLUSIONS

In real-world Australian population, treatment choices differed based on KRAS status and will likely change with the availability of newer drugs on the pharmaceutical benefits scheme. Survival outcomes are comparable to newer agents in clinical trials for select patients.

The Role of Anti-EGFR Monoclonal Antibody in mCRC Maintenance Therapy

Background: Epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) combined with chemotherapy in patients with RAS (rat sarcoma viral oncogene homolog) wild-type metastatic colorectal cancer (mCRC) can alleviate and stabilize the disease, effectively prolong the progression-free survival (PFS) and overall survival (OS), and improve the overall response rate (ORR), which is the first-line treatment standard scheme for RAS wild-type mCRC currently. However, whether anti-EGFR mAb can be used for the maintenance treatment after the first-line treatment of mCRC remains controversial. We reviewed the recent studies on anti-EGFR mAb. The contents include five parts, introduction, anti-EGFR mAb in mCRC and its status in first-line therapy, establishment of the maintenance treatment pattern after the standard first-line treatment for mCRC, research progress of anti-EGFR mAb in mCRC maintenance therapy, and conclusion. More studies support the maintenance treatment of anti-EGFR mAb, but some researchers raise the problems about high cost and drug resistance. Despite lack of the maintenance evidence of anti-EGFR mAb, especially lack of large-scale phase III prospective clinical trials, with the emergence of new evidence and more accurate screening of treatment-dominant groups, maintenance therapy with anti-EGFR mAb monotherapy or anti-EGFR mAb combined with fluorouracil-based schemes after first-line chemotherapy combined with anti-EGFR mAb therapy might strive for more treatment opportunities, optimize treatment strategies and prolong treatment continuity, and finally, lead to more survival benefit for suitable patients.

Systematic literature review and network meta-analysis of pembrolizumab versus other interventions for previously untreated, unresectable or metastatic, microsatellite instability-high or mismatch repair-deficient colorectal cancer

Aim: To compare pembrolizumab with competing interventions for previously untreated, unresectable or metastatic microsatellite instability-high or mismatch repair-deficient colorectal cancer. Method: Trials were identified via a systematic literature review and synthesized using a Bayesian network meta-analysis with time-varying hazard ratios (HRs). Results: Using intention-to-treat data, HRs for overall survival were generally in favor of pembrolizumab but not statistically significant; however, statistical significance was reached versus all comparators by month 16 when accounting for crossover. Estimated HRs for progression-free survival significantly favored pembrolizumab versus all comparators by month 12. Pembrolizumab was also superior to all comparators in terms of grade ≥3 adverse events. Conclusion: These analyses suggest that pembrolizumab is a highly efficacious and safe treatment in this population.

Systematic review of randomised clinical trials and observational studies for patients with RAS wild-type or BRAFV600E-mutant metastatic and/or unresectable colorectal cancer

Approximately 8-10% of metastatic colorectal cancer (mCRC) tumours harbour BRAF^V600E mutations. Eleven randomised controlled trials (RCTs) and 24 non-RCTs were identified. Seven studies evaluated BRAF inhibitors. Single-agent BRAF inhibitors had minimal efficacy, whereas BRAF inhibitor plus anti-EGFR therapy improved outcomes. In BEACON CRC, overall survival (OS) was significantly longer for patients receiving encorafenib plus cetuximab ± binimetinib when compared with irinotecan/FOLFIRI plus cetuximab as second- and third-line therapy. Seven prospective non-RCTs reported worse OS and progression-free survival (PFS) for patients with BRAF^V600E-mutant vs BRAF wild-type mCRC. Eight RCTs reported that PFS and OS were generally shorter for patients with BRAF^V600E-mutant mCRC vs those with KRAS or RAS wild-type mCRC. Patients with BRAF^V600E-mutant mCRC have worse outcomes with conventional therapy vs patients with BRAF wild-type tumours. BRAF inhibitors in conjunction with anti-EGFR therapy improves outcomes for patients with BRAF^V600E-mutant mCRC vs conventional therapy or a BRAF inhibitor alone.

Frequency and Clinicopathological Characteristics of Patients With KRAS/BRAF Double-Mutant Colorectal Cancer: An In Silico Study

KRAS and BRAF mutations are currently thought to be mutually exclusive as their co-occurrence is extremely rare. Therefore, clinicopathological and molecular characteristics of colorectal carcinoma with KRAS/BRAF double mutations are unclear. We aimed to investigate the frequency and clinicopathological characteristics of double-mutant colorectal carcinoma and its differences from KRAS/BRAF single-mutant colorectal carcinoma using bioinformatics tools. We estimated the KRAS/BRAF double mutation frequency in the whole exon and coding sequences via bioinformatic analyses of three datasets from cBioPortal. We compared the clinicopathological characteristics, microsatellite instability status, BRAF classification, and tumor mutation burden of patients harboring the double mutants with those of patients harboring KRAS or BRAF single mutations. We integrated three large datasets and found that the frequency of the KRAS/BRAF double mutation in the dataset was 1.2% (29/2347). The double mutation occurred more frequently in males, with a slightly higher occurrence in the right side of the colon. Sex, histological type, histological grade, microsatellite instability, and tumor mutation burden of the patients harboring KRAS-mutant, BRAF-mutant, and double-mutant colorectal carcinoma varied significantly. The frequency of double-mutant colorectal carcinoma was 60 times higher than that previously reported. Significantly fewer double-mutant colorectal carcinoma cases were classified as BRAF class 1 and more were classified as unknown. Our findings indicate that the biological characteristics of double-mutant tumors are different from those of single-mutant tumors.

Liquid Biopsy and Artificial Intelligence as Tools to Detect Signatures of Colorectal Malignancies: A Modern Approach in Patient's Stratification

Colorectal cancer (CRC) is the second most frequently diagnosed type of cancer and a major worldwide public health concern. Despite the global efforts in the development of modern therapeutic strategies, CRC prognosis is strongly correlated with the stage of the disease at diagnosis. Early detection of CRC has a huge impact in decreasing mortality while pre-lesion detection significantly reduces the incidence of the pathology. Even though the management of CRC patients is based on robust diagnostic methods such as serum tumor markers analysis, colonoscopy, histopathological analysis of tumor tissue, and imaging methods (computer tomography or magnetic resonance), these strategies still have many limitations and do not fully satisfy clinical needs due to their lack of sensitivity and/or specificity. Therefore, improvements of the current practice would substantially impact the management of CRC patients. In this view, liquid biopsy is a promising approach that could help clinicians screen for disease, stratify patients to the best treatment, and monitor treatment response and resistance mechanisms in the tumor in a regular and minimally invasive manner. Liquid biopsies allow the detection and analysis of different tumor-derived circulating markers such as cell-free nucleic acids (cfNA), circulating tumor cells (CTCs), and extracellular vesicles (EVs) in the bloodstream. The major advantage of this approach is its ability to trace and monitor the molecular profile of the patient's tumor and to predict personalized treatment in real-time. On the other hand, the prospective use of artificial intelligence (AI) in medicine holds great promise in oncology, for the diagnosis, treatment, and prognosis prediction of disease. AI has two main branches in the medical field: (i) a virtual branch that includes medical imaging, clinical assisted diagnosis, and treatment, as well as drug research, and (ii) a physical branch that includes surgical robots. This review summarizes findings relevant to liquid biopsy and AI in CRC for better management and stratification of CRC patients.

Final results of the IFCT-0803 study, a phase II study of cetuximab, pemetrexed, cisplatin, and concurrent radiotherapy in patients with locally advanced, unresectable, stage III, non-squamous, non-small-cell lung cancer

PURPOSE

Roughly 20% of patients with non-small-cell lung cancer exhibit locally advanced, unresectable, stage III disease. Concurrent platinum-based chemoradiotherapy is the backbone treatment, which is followed by maintenance immunotherapy, yet with poor long-term prognosis. This phase II trial (IFCT-0803) sought to evaluate whether adding cetuximab to cisplatin and pemetrexed chemoradiotherapy would improve its efficacy in these patients.

MATERIALS AND METHODS

Eligible patients received weekly cetuximab (loading dose 400mg/m² day 1; subsequent weekly 250mg/m² doses until two weeks postradiotherapy). Chemotherapy comprised cisplatin (75mg/m²) and pemetrexed (500mg/m²), both delivered on day 1 of a 21-day cycle of maximally four. Irradiation with maximally 66Gy started on day 22. Disease control rate at week 16 was the primary endpoint.

RESULTS

One hundred and six patients were included (99 eligible patients). Compliance exceeded 95% for day 1 of chemotherapy cycles 1 to 4, with 76% patients receiving the 12 planned cetuximab doses. Maximal grade 3 toxicity occurred in 63% patients, and maximal grade 4 in 9.6%. The primary endpoint involving the first 95 eligible patients comprised two (2.1%) complete responses, 57 (60.0%) partial responses, and 27 (28.4%) stable diseases. This 90.5% disease control rate (95% confidence interval [95% CI]: 84.6%-96.4%) was achieved at week 16. After median 63.0-month follow-up, one-year and two-year survival rates were 75.8% and 59.5%. Median overall survival was 35.8months (95% CI: 23.5-NR), and median progression-free survival 14.4months (95% CI: 11.2-18.8), with one-year and two-year progression-free survival rates of 57.6% and 34.3%.

CONCLUSION

These survival rates compare favourably with published data, thus justifying further development of cetuximab-based induction chemoradiotherapy.

Colorectal liver metastasis: molecular mechanism and interventional therapy

Colorectal cancer (CRC) is one of the most frequently occurring malignancy tumors with a high morbidity additionally, CRC patients may develop liver metastasis, which is the major cause of death. Despite significant advances in diagnostic and therapeutic techniques, the survival rate of colorectal liver metastasis (CRLM) patients remains very low. CRLM, as a complex cascade reaction process involving multiple factors and procedures, has complex and diverse molecular mechanisms. In this review, we summarize the mechanisms/pathophysiology, diagnosis, treatment of CRLM. We also focus on an overview of the recent advances in understanding the molecular basis of CRLM with a special emphasis on tumor microenvironment and promise of newer targeted therapies for CRLM, further improving the prognosis of CRLM patients.

The EPH/Ephrin System in Colorectal Cancer

The EPH/ephrin system constitutes a bidirectional signaling pathway comprised of a family of tyrosine kinase receptors in tandem with their plasma membrane-bound ligand (ephrins). Its significance in a wide variety of physiologic and pathologic processes has been recognized during the past decades. In carcinogenesis, EPH/ephrins coordinate a wide spectrum of pathologic processes, such as angiogenesis, vessel infiltration, and metastasis. Despite the recent advances in colorectal cancer (CRC) diagnosis and treatment, it remains a leading cause of death globally, accounting for 9.2% of all cancer deaths. A growing body of literature has been published lately revitalizing our scientific interest towards the role of EPH/ephrins in pathogenesis and the treatment of CRC. The aim of the present review is to present the recent CRC data which might lead to clinical practice changes in the future.

Efficacy and safety of aflibercept plus chemotherapy in metastatic colorectal cancer: A systematic review and PRISMA-Compliant single-arm Meta-Analysis of noncomparative clinical studies and randomized controlled trials

WHAT IS KNOWN AND OBJECTIVE

Aflibercept, a recombinant protein designed to suppress the vascular endothelial growth factor (VEGF) signalling pathway, has been used in patients with metastatic colorectal cancer (mCRC). We conducted the first meta-analysis to systematically review the efficacy and safety of aflibercept in mCRC.

METHODS

PubMed Central/Medline, Embase and cochrane library were systematically searched for randomized controlled trials and single-arm clinical trials on aflibercept plus chemotherapy for the treatment of mCRC through 9 September 2021.

RESULTS

Ten studies comprising 2049 patients met the inclusion criteria. The pooled estimate rates were 16.0% for 12mPFS, 64.4% for 12mOS, 32.5% for ORR, 83.5% for DCR, while the rates of III/IV AEs rate were 80.2% respectively. The pooled estimate rates were 16.8% for III/IV diarrhoea, 22.3% for III/IV hypertension, 29.5% for III/IV neutropenia, 7.3% for III/IV proteinuria and 8.6% for III/IV oral mucositis.

CONCLUSIONS

Analysis of data from randomized controlled trials(RCT) and single-arm clinical trials confirmed the good efficacy of aflibercept plus chemotherapy in mCRC, while the safety of the treatment is concerning.

Improved Survival over Time After Resection of Colorectal Liver Metastases and Clinical Impact of Multigene Alteration Testing in Patients with Metastatic Colorectal Cancer

BACKGROUND

The past 20 years have seen advances in colorectal cancer management. We sought to determine whether survival in patients undergoing resection of colorectal liver metastases (CLM) has improved in association with three landmark advances: introduction of irinotecan- and/or oxaliplatin-containing regimens, molecular targeted therapy, and multigene alteration testing.

METHODS

Patients undergoing CLM resection during 1998-2014 were identified and grouped by resection year. The influence of alterations in RAS, TP53, and SMAD4 was evaluated and validated in an external cohort including patients with unresectable metastatic colorectal cancer.

RESULTS

Of 1961 patients, 1599 met the inclusion criteria. Irinotecan- and/or oxaliplatin-containing regimens and molecular targeted therapy were used for more than 50% of patients starting in 2001 and starting in 2006, respectively, so patients were grouped as undergoing resection during 1998-2000, 2001-2005, or 2006-2014. Liver resectability indications expanded over time. The 5-year overall survival (OS) rate was significantly better in 2006-2014, vs. 2001-2005 (56.5% vs. 44.1%, P < 0.001). RAS alteration was associated with worse 5-year OS than RAS wild-type (44.8% vs. 63.3%, P < 0.001). However, OS did not differ significantly between patients with RAS alteration and wild-type TP53 and SMAD4 and patients with RAS wild-type in our cohort (P = 0.899) or the external cohort (P = 0.932). Of 312 patients with genetic sequencing data, 178 (57.1%) had clinically actionable alterations.

CONCLUSION

OS after CLM resection has improved with advances in medical therapy and surgical technique. Multigene alteration testing is useful for prognostication and identification of potential therapeutic targets.

A transcriptomic signature that predicts cancer recurrence after hepatectomy in patients with colorectal liver metastases

BACKGROUND

Cancer recurrence is an important predictor of survival outcomes in patients with colorectal cancer-associated liver metastasis (CRLM), who undergo radical hepatectomy. Therefore, identification of patients with the greatest risk of recurrence is critical for developing a precision oncology strategy that might include frequent surveillance (in low-risk patients) or a more aggressive treatment approach (in high-risk patients). We performed genome-wide expression profiling, to identify and develop a transcriptomic signature for predicting recurrence in patients with CRLM.

METHODS

We analysed a total of 383 patients with CRLM, including 63 patients from a publicly available data set (the NCBI's Gene Expression Omnibus with accession number GSE81423). and 320 patients from whom surgical specimens were collected for independent training (n = 169) and validation (n = 151) of identified biomarkers. Using Cox's proportional hazard regression analysis, we evaluated the clinical significance of the identified gene signature by comparing its performance with several key clinical factors.

RESULTS

We identified a six-gene panel that robustly categorised patients with recurrence in the discovery (area under the curve (AUC) = 0.90). We showed that the panel was a significant predictor of recurrence in the clinical training (AUC = 0.83) and validation cohorts (AUC = 0.81). By combining our panel with key clinical factors, we established a risk-stratification model that emerged as an independent predictor of recurrence (AUC = 0.85; univariate: hazard ratio (HR) = 4.34, 95% confidence interval (CI) = 2.71-6.93, P < 0.001; multivariate: HR = 3.40, 95% CI = 1.76-6.56, P < 0.001). The stratification model revealed recurrence prediction in 89% of high-risk group and non-recurrence in 62% of low-risk group.

CONCLUSIONS

We established a novel transcriptomic signature that robustly predicts recurrence, which has significant implications for the management of patients with CRLM.

A randomized controlled trial of surgery and postoperative modified FOLFOX6 versus surgery and perioperative modified FOLFOX6 plus cetuximab in patients with KRAS wild-type resectable colorectal liver metastases: EXPERT study

PURPOSE

To clarify the efficacy of perioperative chemotherapy for the patients with resectable colorectal liver metastases (CLM), we conducted a multicenter randomized phase III trial to compare surgery followed by postoperative FOLFOX regimen with perioperative FOLFOX regimen plus cetuximab in patients with KRAS wild-type resectable CLM.

METHODS

Patients who had KRAS wild-type resectable CLM having one to eight liver nodules without extrahepatic disease were randomly assigned to the postoperative chemotherapy group, wherein up-front hepatectomy was performed followed by 12 cycles of postoperative modified FOLFOX6, and the perioperative chemotherapy group (experimental), wherein six cycles of preoperative modified FOLFOX6 plus cetuximab were performed followed by hepatectomy and six cycles of postoperative modified FOLFOX6 plus cetuximab. The primary endpoint was progression-free survival (PFS).

RESULTS

There were 37 patients in postoperative chemotherapy group and 40 patients in the perioperative chemotherapy group who were analyzed. Baseline characteristics were well-balanced between groups. The PFS and overall survival (OS) showed no significant difference (PFS, hazard ratio 1.18 [95% confidence interval 0.69-2.01], P = 0.539: OS, 1.03 [0.46-2.29], P = 0.950). In the postoperative chemotherapy group, 35.1% had a 3-year PFS, and 86.5% had a 3-year OS. Meanwhile, in the perioperative chemotherapy group, 30.0% had a 3-year PFS, and 74.4% had a 3-year OS.

CONCLUSION

There was no difference in survival found between the group of the perioperative chemotherapy plus cetuximab and that of the postoperative chemotherapy in the cohort of our study. The study was registered in the University Hospital Medical Information Network (UMIN000007787).

Efficacy and Safety of Systemic Treatments Among Colorectal Cancer Patients: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Systemic treatments, namely, either monotherapy or combination therapy, are commonly administered to patients with advanced or metastatic colorectal cancer (CRC). This study aimed to provide the complete efficacy and safety profiles and ranking of systemic therapies for the treatment of unresectable advanced or metastatic CRC.

METHODS

We searched PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception until June 30, 2021, and also the bibliographies of relevant studies. Randomized controlled trials comparing two or more treatments, namely, at least capecitabine, 5-fluorouracil, leucovorin, irinotecan, bevacizumab, cetuximab, oxaliplatin, or panitumumab were investigated. A network meta-analysis using the Bayesian approach was performed to compare the efficacy and safety of treatments. The surface under the cumulative ranking curve (SUCRA) was calculated for the probability of each treatment as the most effective. The overall response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), adverse events (AEs) grade ≥3, and serious adverse events (SAEs) were evaluated.

RESULTS

One hundred two publications with 36,147 participants were assigned to 39 different treatments. Among 11 treatments with full information on six outcomes, FOLFIRI/FOLFOX/FOLFOXIRI + bevacizumab significantly improved both the ORR and DCR, compared to FOLFIRI. Although FOLFOX and FOLFIRI/FOLFOX + cetuximab significantly prolonged both OS and PFS, treatments were comparable in terms of AEs grade ≥3 and SAEs. The top highest SUCRA values were observed in the FOLFOXIRI + panitumumab group for ORR (96%) and DCR (99%), FOLFIRI + bevacizumab + panitumumab group for OS (62%) and PFS (54%), and FOLFOXIRI + bevacizumab group for AEs grade ≥3 (59%) and SAEs (59%) outcomes.

CONCLUSIONS

These findings suggest an available range of systemic treatment therapies with different efficacy and safety profiles with patients. Further investigations of the side effects and mutation status are required to confirm our findings.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42019127772.

Precision medicine for metastatic colorectal cancer in clinical practice

Globally, metastatic colorectal cancer is one of the leading causes for cancer-related death. Treatment limited to conventional chemotherapeutics extended life for only a few months. However, advances in surgical approaches and medical treatment regimens have greatly increased survival, even leading to long-term remission in selected patients. Advances in multiomics analysis of tumors have built a foundation for molecular-targeted therapies. Furthermore, immunotherapies are on the edge of revolutionizing oncological practice. This review summarizes recent advances in the growing toolbox of personalized treatment for patients with metastatic colorectal cancer. We provide an overview of current multimodal therapy and explain novel immunotherapy and targeted therapy approaches in detail. We emphasize clinically relevant therapies, such as inhibitors of MAPK signaling, and give recommendations for clinical practice. Finally, we describe the potential predictive impact of molecular subtypes and provide an outlook on novel concepts, such as functional precision medicine.

Epidermal Growth Factor Receptor as Target for Perioperative Elimination of Circulating Colorectal Cancer Cells

Surgical resection of the tumor is the primary treatment of colorectal cancer patients. However, we previously demonstrated that abdominal surgery promotes the adherence of circulating tumor cells (CTC) in the liver and subsequent liver metastasis development. Importantly, preoperative treatment with specific tumor-targeting monoclonal antibodies (mAb) prevented surgery-induced liver metastasis development in rats. This study investigated whether the epidermal growth factor receptor (EGFR) represents a suitable target for preoperative antibody treatment of colorectal cancer patients undergoing surgery. The majority of patients with resectable colorectal liver metastases were shown to have EGFR + CTCs. Three different anti-EGFR mAbs (cetuximab, zalutumumab, and panitumumab) were equally efficient in the opsonization of tumor cell lines. Additionally, all three mAbs induced antibody-dependent cellular phagocytosis (ADCP) of tumor cells by macrophages at low antibody concentrations in vitro, independent of mutations in EGFR signaling pathways. The plasma of cetuximab-treated patients efficiently opsonized tumor cells ex vivo and induced phagocytosis. Furthermore, neither proliferation nor migration of epithelial cells was affected in vitro, supporting that wound healing will not be hampered by treatment with low anti-EGFR mAb concentrations. These data support the use of a low dose of anti-EGFR mAbs prior to resection of the tumor to eliminate CTCs without interfering with the healing of the anastomosis. Ultimately, this may reduce the risk of metastasis development, consequently improving long-term patient outcome significantly.

Efficacy and safety of immune checkpoint inhibitors in colorectal cancer: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Immune checkpoint inhibitor (ICI) therapies have shown promising prospects in colorectal cancer (CRC) immunotherapy; many clinical trials have been carried out. In this study, we sought to evaluate the efficacy and safety of ICI therapies in CRC by presenting a meta-analysis of relevant studies.

METHODS

Databases including PubMed, Embase, Cochrane Library, and Web of Science were systematically searched for studies concerning the efficacy and safety of ICI in colorectal cancer. The reported odds ratio (OR) or weighted mean difference (WMD) with 95% confidence intervals (CIs) of overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), treatment-related adverse events (TRAEs), and TRAEs ≥ 3 in the included studies were analyzed by fixed effects/random effects models.

RESULTS

Three studies involving 667 patients with colorectal cancer were included in our meta-analysis. No significant difference between the immune checkpoint inhibitor therapies and conventional therapies in OS (WMD = 0.73, 95% CI - 3.09, 4.54; p = 0.71), in ORR (OR = 1.54, 95% CI 0.98, 2.40; p = 0.06), and in DCR (OR = 0.97, 95% CI 0.36, 2.61; p = 0.95). The median PFS of the ICI therapy group was shorter than that of the conventional therapy group (WMD =  - 0.10, 95% CI - 0.18, - 0.02; p = 0.02). At the same time, we also could not find a significant difference between the immune checkpoint inhibitor therapies and conventional therapies in TRAEs (OR = 1.56, 95% CI 0.11, 22.09; p = 0.74) and in TRAEs ≥ 3 (OR = 0.94, 95% CI 0.16, 5.65; p = 0.95).

CONCLUSION

Immune checkpoint inhibitor therapies could not improve all survival endpoints to advanced or metastatic colorectal cancer patients. Whether immune checkpoint inhibitors should be the first choice of therapies for colorectal cancer patients with undetermined microsatellite status or not able to determine microsatellite status needs more related studies to prove.

EUS-FNA Biopsies to Guide Precision Medicine in Pancreatic Cancer: Results of a Pilot Study to Identify KRAS Wild-Type Tumours for Targeted Therapy

Background

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer death and lacks effective treatment options. Diagnostic endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsies represent an appealing source of material for molecular analysis to inform targeted therapy, as they are often the only available tissue for patients presenting with PDAC irrespective of disease stage. However, EUS-FNA biopsies are typically not used to screen for precision medicine studies due to concerns about low tissue yield and quality. Epidermal growth factor receptor (EGFR) inhibition has shown promise in clinical trials of unselected patients with advanced pancreatic cancer, but has not been prospectively tested in KRAS wild-type patients. Here, we examine the clinical utility of EUS-FNA biopsies for molecular screening of KRAS wild-type PDAC patients for targeted anti-EGFR therapy to assess the feasibility of this approach.

Patients and Methods

Fresh frozen EUS-FNA or surgical biopsies from PDAC patient tumours were used to screen for KRAS mutations. Eligible patients with recurrent, locally advanced, or metastatic KRAS wild-type status who had received at least one prior line of chemotherapy were enrolled in a pilot study (ACTRN12617000540314) and treated with panitumumab at 6mg/kg intravenously every 2 weeks until progression or unacceptable toxicity. The primary endpoint was 4-month progression-free survival (PFS).

Results

275 patient biopsies were screened for KRAS mutations, which were detected in 88.3% of patient samples. 8 eligible KRAS wild-type patients were enrolled onto the interventional study between November 2017 and December 2020 and treated with panitumumab. 4-month PFS was 14.3% with no objective tumour responses observed. The only grade 3/4 treatment related toxicity observed was hypomagnesaemia.

Conclusions

This study demonstrates proof-of-principle feasibility to molecularly screen patients with pancreatic cancer for targeted therapies, and confirms diagnostic EUS-FNA biopsies as a reliable source of tumour material for molecular analysis. Single agent panitumumab was safe and tolerable but led to no objective tumour responses in this population.

Mucinous adenocarcinoma: A unique clinicopathological subtype in colorectal cancer

Mucinous adenocarcinoma (MAC) is a unique clinicopathological subtype of colorectal cancer, which is characterized by extracellular mucinous components that comprise at least 50% of the tumor tissue. The clinical characteristics, molecular features, response to chemo-/radiotherapy, and prognosis of MAC are different from that of non-MAC (NMAC). MAC is more common in the proximal colon, with larger volume, higher T-stage, a higher proportion of positive lymph nodes, poorer tumor differentiation, and a higher proportion of peritoneal implants compared to NMAC. Although biopsy is the main diagnostic method for MAC, magnetic resonance imaging is superior in accuracy, especially for rectal carcinoma. The aberrant expression of mucins, including MUC1, MUC2 and MUC5AC, is a notable feature of MAC, which may be related to tumor invasion, metastasis, inhibition of apoptosis, and chemo-/radiotherapy resistance. The genetic origin of MAC is mainly related to BRAF mutation, microsatellite instability, and the CpG island methylator phenotype pathway. In addition, the poor prognosis of rectal MAC has been confirmed by various studies, and that of colonic MAC is still controversial. In this review, we summarize the epidemiology, clinicopathological characteristics, molecular features, methods of diagnosis, and treatments of MAC in order to provide references for further fundamental and clinical research.

Application of Tumor Burden Score for predicting conversion outcome in patients with initially unresectable colorectal liver metastases after first-line systemic therapy

BACKGROUND

Patients with initially unresectable colorectal liver metastases (CRLM) could achieve survival benefit from successful conversion therapy. Recently, Tumor Burden Score (TBS) was proposed as a valuable index to predict outcome following resection of CRLM. The study is aimed to investigate the association of TBS with conversion outcome.

METHODS

A total of 234 patients who underwent first-line treatment in our center were enrolled as training cohort. The validation cohort was developed from 89 patients in our previous study. Cut-off value of TBS was calculated to stratify patients into two groups. Significance test and logistic regression model were used to examine the prediction value of TBS for conversion outcome after first-line systemic therapy. Kaplan-Meier method and Cox proportional hazard model were applied to assess the prognostic value of TBS.

RESULTS

TBS showed good discriminatory power [area under curve (AUC) 0.726, p < 0.001] with cut-off value defined as 14.3 in training cohort, which was validated in the validation cohort. Increasing TBS was related to adverse chemotherapy response and conversion outcome. Low TBS group had three times higher conversion rate than that in high TBS group (57.3% versus 19.0%, p < 0.001). Multivariate analysis indicated that high TBS [odds ratio (OR) = 3.676, 95% confidence interval (CI) 1.671-8.429, p = 0.002], first-line treatment response as stable disease (SD) or progressive disease (PD) (OR = 9.247; 95% CI 4.736-18.846, p < 0.001), and absence of targeted therapy (OR = 2.453, 95% CI 1.139-5.455, p = 0.024) were three independent risk factors for failure conversion outcome. High TBS was significantly associated with conversion outcome whatever chemotherapy response, addition of targeted therapy, and Kirsten rat sarcoma viral oncogene homolog (KRAS) status. High TBS was also associated with worse overall survival.

CONCLUSION

TBS should be applied in clinical practice to predict conversion outcome in patients with initially unresectable CRLM.

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.

Comparative Effectiveness of Biologic Agents Among Black and White Medicare Patients in the US With Metastatic Colorectal Cancer

Importance

Randomized clinical trials have defined the survival benefit provided by the addition of biologic drugs to chemotherapy in patients with metastatic colorectal cancer (mCRC). However, Black patients may be underrepresented in trial populations, and outcomes in this group remain poorly defined.

Objective

To determine whether the real-world benefit of biologic drugs in Black patients is consistent with the real-world benefit of biologic drugs in White patients using a comparative effectiveness research approach.

Design, Setting, and Participants

Population-based retrospective comparative effectiveness analysis of a cohort of patients aged 65 years or older with mCRC diagnosed between 2004 and 2011 who had received at least 1 dose of chemotherapy and had complete Medicare claims data using the Surveillance, Epidemiology, and End Result (SEER)-Medicare linked database. Data were analyzed from August 1, 2020, to March 31, 2021.

Interventions

Patient data were classified according to whether patients received chemotherapy (oxaliplatin, irinotecan, and 5-fluorouracil or capecitabine) or biochemotherapy (bevacizumab, cetuximab, panitumumab, ramucirumab, or aflibercept, started within 3 months of chemotherapy).

Main Outcomes and Measures

Overall survival (OS) defined as the time from starting chemotherapy to death or last follow-up. A weighted Cox regression model was used to assess differences in survival.

Results

A total of 5617 patients with mCRC were identified in the SEER-Medicare linked database, and 4542 patients were included in the main analysis. Of the 5617 patients, 3969 (70.7%) received biologic agents at any point between 2004 and 2011; biologic agent therapy was started within 3 months of chemotherapy in 2894 patients (72.9%). Among 4542 patients with data on race and ethnicity, the median age was 72 years (IQR, 68-78 years), 2365 (52.0%) were female, 3445 (75.8%) had colon as the primary site, 552 (12.2%) were Black patients, and 3990 (87.8%) were White patients. There was no difference in the receipt of 1 (76.7% and 74.8%) vs 2 or more (23.3% and 25.2%: P = .92) lines of therapy, and in the receipt of biologic agents (63.6% vs 64.3% P = .33), among White patients and Black patients, respectively. Biochemotherapy was associated with a significant survival benefit compared with chemotherapy alone in the overall population (biochemotherapy median OS, 17.9 [95% CI, 17.3-18.7] months vs chemotherapy median OS, 8.3 [95% CI, 9.1-9.9] months; P < .001). The survival benefit was similar among White patients (17.8 vs 9 months; average hazard ratio, 0.59; 95% CI, 0.55-0.64; P < .001) and Black patients (18.6 vs 9.9; average hazard ratio, 0.58; 95% CI, 0.47-0.71; P < .001).

Conclusions and Relevance

In this comparative effectiveness analysis of a cohort of Medicare recipients with mCRC, biochemotherapy was associated with an improvement in OS with a similar rate of reduction in mortality among Black and White patients. Clinicians may offer biochemotherapy therapy to all patients to maximize clinical benefit, factoring in clinical variables, but not their race.

Short-course radiotherapy and chemotherapy for conversion surgery in patients with unresectable metastatic rectal cancer: a preliminary case series study

Purpose

Curative treatment is challenging in patients with locally advanced rectal cancer and unresectable metastases. The aim of this study was to evaluate the clinical outcomes of short-course radiotherapy (RT) followed by systemic chemotherapy for patients with rectal cancer with mesorectal fascia (MRF) involvement and unresectable distant metastases.

Methods

The study included consecutive patients diagnosed as having metastatic mid-to-low rectal cancer treated with short-course RT followed by systemic chemotherapy for conversion radical or palliative surgery between 2014 and 2019 at Gil Medical Center. The patients had primary rectal tumors involving the MRF and unresectable distant metastases. The treatment strategies were determined in a multidisciplinary team discussion.

Results

Seven patients (five men and two women) underwent short-course RT (5×5 Gy) and preoperative systemic chemotherapy. The median age was 68 years (range, 46-84 years), and the median distance from the anal verge to the primary tumor was 6.0 cm (range, 2.0-9.0 cm). During the median follow-up period of 29.4 months, three patients underwent conversion radical surgery with R0 resection, two underwent palliative surgery, and two could not undergo surgery. No postoperative major morbidity or mortality occurred. The patients who underwent conversion complete radical surgery showed good long-term survival outcomes, with an overall survival time of 29.4-48.8 months and progression-free survival time of 14.7-41.1 months.

Conclusion

Short-course RT followed by systemic chemotherapy could provide patients with unresectable stage IV rectal cancer a chance to undergo to conversion radical surgery with good long-term survival outcomes.

Liver transplantation for advanced liver-only colorectal metastases

Liver transplantation provided a 5-year overall survival rate of 100 per cent in patients with colorectal cancer who had undergone liver resection previously. Patients with extensive liver metastases (over 20 lesions) and a left-sided primary tumour had long survival, whereas those with an ascending colonic primary tumour had inferior survival after liver transplantation.

Depletion of METTL3 alters cellular and extracellular levels of miRNAs containing m6A consensus sequences

Extracellular vesicles (EVs) are capable of transferring cargo from donor to recipient cells, but precisely how cargo content is regulated for export is mostly unknown. For miRNA cargo, we previously showed that when compared to isogenic colorectal cancer (CRC) cells expressing wild-type KRAS, a distinct subset of miRNAs are differentially enriched in EVs from KRAS mutant active CRC cells, with miR-100 being one of the most enriched. The mechanisms that could explain how miR-100 and other miRNAs are differentially exported into EVs have not been fully elucidated. Here, we tested the effect of N6-methyladenosine (m6A) modification on miRNA export into EVs by depletion of METTL3 and ALKBH5, a writer and eraser of m6A modification, respectively. While the effects of ALKBH5 knockdown were quite modest, decreased levels of METTL3 led to reduced cellular and extracellular levels of a subset of miRNAs that contain consensus sequences for m6A modification. Functional testing of EVs prepared from cells expressing shRNAs against METTL3 showed that they were less capable of conferring colony growth in 3D to wild-type KRAS cells and were also largely incapable of conferring the spread of cetuximab resistance. Our data support a role for METTL3 modification on cellular miRNA levels and export of specific miRNAs.

BRAF Mutation Is Associated with Hyperplastic Polyp-Associated Gastric Cancer

Gastric hyperplastic polyps (GHP) are frequently found to be benign polyps and have been considered to have a low carcinogenic potential. The characteristics of the hyperplastic polyp-associated gastric cancer (HPAGC) remain unclear. Therefore, we analyzed samples from 102 GHP patients and identified 20 low-grade atypical GHPs (19.6%), 7 high-grade atypical GHPs (6.9%), and 5 intramucosal cancer samples (4.9%). GHP atypia was more common in the elderly and increased with increasing polyp size. In particular, polyps larger than 1 cm were associated with a higher grade and cancer. Furthermore, mucus production decreased with increasing atypia. Although no correlation was found between atypia and Helicobacter pylori infection or intestinal metaplasia, enhanced proliferative ability (Ki-67) did correlate with atypia, as did nuclear 8-hydroxy-2'-deoxyguanosine levels. Interestingly, 4-hydroxynonenal levels in granulation tissue and the area ratio of granulation tissue within polyps also correlated with GHP atypia. In five cases of HPAGC, three cases exhibited caudal type homeobox transcription factor (CDX2)-positive cells and a mixed mucin phenotype, which is considered to be related to H. pylori infection. By contrast, two cases were CDX2 negative, with a gastric mucin phenotype, and H. pylori infection was not observed in the tumor or the surrounding mucosa. In these cases, a v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutation (V600E) was detected. All cancer samples showed high stemness and p53 protein accumulation, but no KRAS mutations. The molecular and phenotypic characteristics of the cases characterized by BRAF mutations may represent a novel subtype of HPAGC, reflecting a conserved pathway to oncogenesis that does not involve H. pylori infection. These findings are worthy of further investigation in a large-scale study with a substantial cohort of HPAGC patients to establish their clinical significance.

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.