Fluorouracil, leucovorin, and oxaliplatin with and without cetuximab in the first-line treatment of metastatic colorectal cancer

A Phase I Study Comparing the Pharmacokinetics, Safety, and Immunogenicity of A140 Injection and Cetuximab (Erbitux®) in Healthy Chinese Male Subjects

INTRODUCTION

This study aimed to compare the pharmacokinetic (PK) profiles, safety, and immunogenicity of the proposed A140 with those of cetuximab (Erbitux®) in healthy Chinese male subjects.

METHODS

We conducted a randomized, single-dose, double-blind, parallel-controlled phase I study in which 82 healthy subjects were randomized equally into the A140 group and the cetuximab group. Both the test and comparator drug were administered as a single intravenous (IV) dose of 250 mg/m2. Blood samples were collected as per a designated schedule to evaluate PKs and immunogenicity. Safety was assessed throughout the study. PK similarity was concluded if the 90% confidence intervals (CIs) for the geometric mean ratios (GMRs) of the A140 to cetuximab for area under the concentration-time curve from time zero to the last measurable concentration (AUC0-t) were within the predefined bioequivalence range of 80-125%.

RESULTS

The results showed that the 90% CI of the GMR for PK parameters (AUC0-t, AUC0-∞, Cmax) between the A140 and cetuximab groups were all within the predefined equivalent interval of 80-125%. Furthermore, the types of treatment-related adverse events were similar between the two groups, with an incidence of 100%. However, approximately 80% of these events belonged to Common Terminology Criteria for Adverse Events (CTCAE) grade 1 or 2. Anti-drug antibody (ADA) profiles were comparable between the A140 and the cetuximab group.

CONCLUSION

A140 demonstrated similar PK to cetuximab and comparable safety and immunogenicity in healthy Chinese male subjects.

TRIAL REGISTRATION

CTR20182229 ( https://www.chinadrugtrials.org.cn/ ).

Physical insights guided rational design of anti-EGFR antibody to reverse the acquired resistance

Cetuximab (Ctx), a monoclonal antibody targeting the epidermal growth factor receptor (EGFR) for colorectal cancer treatment, often faces diminished clinical efficacy due to acquired resistance driven by EGFR mutations. Here, we investigated the molecular mechanisms underlying this mutation-induced drug resistance and developed a mechanism-based strategy to restore the binding affinity of Ctx to EGFR mutants. Through molecular dynamics simulations and free energy perturbation calculations, we discovered that most resistant mutations primarily alter the electrostatic properties of the binding interface. Focusing on two key mutations, EGFR K489E and I491M, we rationally designed two Ctx variants-CtxD103R for EGFRK489E and CtxD103E_E105D for EGFRI491M-using electrostatic compensation and steric hindrance adjustment strategies. Surface plasmon resonance measurements verified that the two designed Ctx variants exhibit improved binding affinity to the corresponding EGFR mutants compared with wild-type Ctx. Additionally, western blot experiments using HEK-293T cells showed that the designed CtxD103R effectively inhibits EGF-stimulated phosphorylation of EGFRK489E. Our findings highlight a rational design approach, empowered by interaction landscape at atomic detail, as a promising and cost-effective strategy to combat mutation-driven resistance in antibody therapies.

Combining treatment effects from mixed populations in meta-analysis: a review of methods

BACKGROUND

Meta-analysis is a useful method for combining evidence from multiple studies to detect treatment effects that could perhaps not be identified in a single study. While traditionally meta-analysis has assumed that populations of included studies are comparable, over recent years the development of precision medicine has led to identification of predictive genetic biomarkers which has resulted in trials conducted in mixed biomarker populations. For example, early trials may be conducted in patients with any biomarker status with no subgroup analysis, later trials may be conducted in patients with any biomarker status and subgroup analysis, and most recent trials may be conducted in biomarker-positive patients only. This poses a problem for traditional meta-analysis methods which rely on the assumption of somewhat comparable populations across studies. In this review, we provide a background to meta-analysis methods allowing for synthesis of data with mixed biomarker populations across trials.

METHODS

For the methodological review, PubMed was searched to identify methodological papers on evidence synthesis for mixed populations. Several identified methods were applied to an illustrative example in metastatic colorectal cancer.

RESULTS

We identified eight methods for evidence synthesis of mixed populations where three methods are applicable to pairwise meta-analysis using aggregate data (AD), three methods are applicable to network meta-analysis using AD, and two methods are applicable to network meta-analysis using AD and individual participant data (IPD). The identified methods are described, including a discussion of the benefits and limitations of each method.

CONCLUSIONS

Methods for synthesis of data from mixed populations are split into methods which use (a) AD, (b) IPD, and (c) both AD and IPD. While methods which utilise IPD achieve superior statistical qualities, this is at the expense of ease of access to the data. Furthermore, it is important to consider the context of the decision problem in order to select the most appropriate modelling framework.

Clinical Impact of Sub-Clonal RAS/BRAF Alterations in Liquid Biopsies From Patients With Advanced or Metastatic CRC

INTRODUCTION

Colorectal cancer (CRC), a global health concern, requires effective treatments. Anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies are used for RAS wild-type and BRAFV600 mutation-negative metastatic CRC (mCRC) but are not indicated for RAS mutant CRC. Evidence suggests CRC patients with sub-clonal RAS/BRAF mutations in tumor tissue may benefit from anti-EGFRs. We assessed the outcomes of patients with sub-clonal RAS/BRAF mutated advanced/mCRC receiving anti-EGFRs using liquid-based GuardantINFORM real-world clinical-genomic analysis.

PATIENTS AND METHODS

GuardantINFORM analyzed US patients with advanced CRC with BRAFV600/KRAS/NRAS mutations who received anti-EGFR therapies within 90 days after a Guardant360 test. Primary endpoints were time-to-next treatment (TTNT) and overall survival (OS) (compared across RAS/BRAF mutation clonality cut-offs of 0.3-0.8 using the Cox proportional hazards model).

RESULTS

In GuardantINFORM, 446 patients initiated anti-EGFR therapy within 90 days after the Guardant360 test, and 11%, 9%, and 1% had BRAFV600E, KRAS, or NRAS mutations, respectively; median distribution of RAS/BRAF clonality was 0.84 (IQR, 0.57-1.00). The data show that patients harboring sub-clonal RAS/BRAF mutations benefited from anti-EGFR therapy to a degree similar to patients without RAS/BRAF mutations. For cut-offs of 0.3 to 0.8, sub-clonal RAS/BRAF had similar TTNT to patients without RAS/BRAF mutations, while clonal RAS/BRAF had a significantly shorter TTNT. For cut-offs of 0.3 to 0.7, sub-clonal RAS/BRAF had similar OS to RAS/BRAF mutations not detected, while clonal RAS/BRAF had a significantly shorter OS.

CONCLUSION

Consistent with tumor tissue biopsy data, patients with CRC harboring sub-clonal RAS/BRAF mutations as assessed by liquid biopsy may derive benefit from anti-EGFR therapy, warranting further investigation.

Depth of response in patients with locally advanced pancreatic cancer treated with first-line chemotherapy: A supplementary analysis of JCOG1407

BACKGROUND/OBJECTIVES

Depth of response (DpR; maximum % reduction from baseline in sum of the target lesion diameters) has demonstrated potential in predicting prognosis in several malignancies. However, its role in locally advanced pancreatic cancer (LAPC) is still unclear. In JCOG1407, modified FOLFIRINOX (mFOLFIRINOX) and gemcitabine plus nab-paclitaxel (GnP) exhibited comparable efficacy for LAPC. In this exploratory analysis using the data of JCOG1407, we focused on the association between DpR and prognosis.

METHODS

DpR was classified into three groups at the tertile point and patients' backgrounds and survival were compared. The impact of DpR on survival outcomes was evaluated using the multivariable Cox proportional hazard model.

RESULTS

Of the 126 patients enrolled in JCOG1407, 109 patients were included, categorized into three DpR groups: T1 (<-37.2 %), T2 (-37.2 to -13.6 %), and T3 (>-13.6 %). The median DpR was significantly greater in the GnP arm than in the mFOLFIRINOX arm (-28.9 vs. -22.7 %, P = 0.041). Median duration of response tended to be shorter in the GnP arm than in the mFOLFIRINOX arm, although the difference was not significant (5.3 vs. 8.2 months, P = 0.132). Greater DpR (T1) had a significantly larger impact on better progression-free survival (PFS) and overall survival (OS) than T3, with the hazard ratio of 0.469 (95 % confidence interval [CI] 0.268-0.821, P = 0.008), and 0.398 (95 % CI 0.217-0.728, P = 0.003), respectively.

CONCLUSIONS

mFOLFIRINOX and GnP had similar OS, it is noteworthy that the regimens exhibited differences in DpR, with GnP leading to greater DpR. Greater DpR are associated with improved survival in patients with LAPC.

Clinical usefulness of anti-α3Gal immunoglobulin E assays for cetuximab-mediated anaphylaxis in head and neck cancer

Background

Fatal anaphylactic reactions to cetuximab remain a clinical issue, although they are associated with preexisting immunoglobulin E (IgE) directed against the galactose-α1,3-galactose epitope (α3Gal). We aimed to compare the clinical usefulness of the two assays and determine the prevalence of preexisting anti-α3Gal IgE.

Patients and methods

An anti-α3Gal IgE assay was developed (70BP assay) and compared with a commercial assay [bovine thyroglobulin (bTG) assay]. Both assays were applied to two cohorts: 299 healthy blood donors and 41 patients with head and neck cancer treated with cetuximab, including four patients with a history of anaphylactic reaction (9.8%).

Results

The prevalence of anti-α3Gal IgE was 6% and 5% using 70BP and bTG assays, respectively, in healthy blood donors. Among the head and neck cancer patients, the four who had an anaphylactic reaction were included in the seven (17.1%) and six (14.6%) patients with a signal above the detection threshold using the 70BP and bTG assays, respectively. This resulted in a sensitivity and negative predictive value of 100% for both assays, with a specificity of 91.9% and 94.6%, respectively, and a positive predictive value of 57.1% and 66.6% for the 70BP and bTG assays, respectively. Using an optimized threshold in the bTG assay, the prevalence of anti-α3Gal IgE in blood donors decreased to 1.3%, and five patients (12.2%) were eventually considered positive, giving a specificity of 97.3% and a positive predictive value of 80%.

Conclusion

The predictive value of anti-α3Gal IgE using these two assays was excellent and useful in clinical practice.

Gut microbiota derived DCA enhances FOLFOX efficacy via Ugt1a6b mediated enterohepatic circulation in colon cancer

FOLFOX (5-Fluorouracil, Calcium Folinate combined with Oxaliplatin) is a preferred chemotherapy regimen for colon cancer, but its limited efficacy remains a major challenge, significantly impairs patient outcomes. There is an urgent need to identify strategies to improve its therapeutic effectiveness. Our previous studies have suggested that gut microbiota-derived bile acids may be involved in the anticancer effect of FOLFOX in vitro, however, the underlying mechanism remains unclear. In this study, we investigated the role of bile acids in modulating FOLFOX efficacy and the related mechanisms. We first demonstrated that bile acids depletion (cholestyramine treatment) enhanced FOLFOX efficacy in an orthotopic colon cancer mouse model, suggesting that bile acids play a key role in FOLFOX's therapeutic effects. Further, based on the system screen of 15 bile acids on FOLFOX efficacy via MTT, colony formation and flow cytometry assay, Deoxycholic Acid (DCA) and Glycodeoxycholic Acid (GDCA) were annotated as potential modulators of FOLFOX efficacy. Among these, DCA was further validated to significantly enhance FOLFOX's anti-colon cancer effects in vivo. Transcriptomic analysis and subsequent biological experiments revealed that DCA enhanced FOLFOX efficacy via Ugt1a6b. In conclusion, our findings establish that gut microbiota-derived DCA enhances the efficacy of FOLFOX potentially via Ugt1a6b mediated enterohepatic circulation, providing novel insights into a synergistic therapeutic strategy for improving colon cancer treatment.

A surgical orthotopic xenograft approach with immune response for colorectal cancer research

The high morbidity and mortality of colorectal cancer (CRC) is a major challenge in clinical practice. Although a series of alternative research models of CRC have been developed, appropriate orthotopic animal models that reproduce the specific clinical response as well as pathophysiological immune features of CRC are still lacking. In the current study, we constructed a CRC orthotopic xenograft model by implanting the tumor tubes at the colorectum of mice and monitored the model development using bioluminescence imaging. This model successfully recapitulates the clinical chemotherapy efficacy, including reduced total flux, tumor weight, and the expression of Ki67 after treatment of the first-line chemotherapy regime of CRC (FOLFOX: oxaliplatin and 5-fluorouracil/calcium folinate). The model also reproduced the immunosuppressive effect of FOLFOX, indicated by decreased infiltration of macrophages and increased Treg cells in tumor. Additionally, the orthotopic xenograft approach may be applied in immunodeficient NCG/NSG mice for constructing patient-derived xenografts, and being used in clinical precision medicine and drug evaluation. We believe the current model is a successful surgical orthotopic xenograft approach for cancer research and deserves to be popularized, which will provide a convenient and efficient platform for in-depth mechanism exploration of CRC and preclinical drug evaluation.

The impact of combining cetuximab with the traditional chemotherapy regimens on clinical effectiveness in metastatic colorectal cancer: a systematic review and meta-analysis

BACKGROUND

Metastatic colorectal cancer (mCRC) poses a high rate of morbidity and mortality despite various treatment advances. Cetuximab, an anti-EGFR, has shown promising efficacy in improving outcomes when combined with chemotherapy. Understanding its efficacy is essential for optimizing treatment strategies in mCRC. This systematic review and meta-analysis aims to evaluate the effectiveness of combining cetuximab with chemotherapy in mCRC.

METHODS

PubMed and Google Scholar were systematically searched following the benchmarks indicated by PRISMA. The primary outcomes of the study were progression-free survival (PFS) and overall survival (OS). Statistical analyses were executed using Stata version 16.

RESULTS

The meta-analysis encompassed 25 studies involving 3788 mCRC patients. The median age spans from 18 to 77 years. The cetuximab plus chemotherapy exhibited a higher PFS and OS with a significant difference (PFS: HR = 0.79, 95% CI = 0.63-0.96, p < 0.01, I2 = 38% and OS: HR = 0.78, 95% CI = 0.60-0.91, p < 0.01, I2 = 47%) compared to the control group. Subgroup analysis based on randomized controlled trials demonstrated consistent treatment effects for PFS (HR = 0.77, 95% CI = 0.62-0.93) and OS (HR = 0.76, 95% CI = 0.61-0.88) in the cetuximab treatment group.

CONCLUSIONS

Combining cetuximab with chemotherapy offers a potential benefit in improving survival outcomes for metastatic colorectal cancer patients, as indicated by this study. These results suggest that cetuximab may be a valuable addition to mCRC treatment strategies, warranting further clinical investigation and integration into standard care.

Invasion and metastasis in cancer: molecular insights and therapeutic targets

The progression of malignant tumors leads to the development of secondary tumors in various organs, including bones, the brain, liver, and lungs. This metastatic process severely impacts the prognosis of patients, significantly affecting their quality of life and survival rates. Research efforts have consistently focused on the intricate mechanisms underlying this process and the corresponding clinical management strategies. Consequently, a comprehensive understanding of the biological foundations of tumor metastasis, identification of pivotal signaling pathways, and systematic evaluation of existing and emerging therapeutic strategies are paramount to enhancing the overall diagnostic and treatment capabilities for metastatic tumors. However, current research is primarily focused on metastasis within specific cancer types, leaving significant gaps in our understanding of the complex metastatic cascade, organ-specific tropism mechanisms, and the development of targeted treatments. In this study, we examine the sequential processes of tumor metastasis, elucidate the underlying mechanisms driving organ-tropic metastasis, and systematically analyze therapeutic strategies for metastatic tumors, including those tailored to specific organ involvement. Subsequently, we synthesize the most recent advances in emerging therapeutic technologies for tumor metastasis and analyze the challenges and opportunities encountered in clinical research pertaining to bone metastasis. Our objective is to offer insights that can inform future research and clinical practice in this crucial field.

High-salt diet decreases FOLFOX efficacy via gut bacterial tryptophan metabolism in colorectal cancer

BACKGROUND

FOLFOX is the recommended chemotherapy regimen for colorectal cancer (CRC), but its response rate remains low. Our previous studies have established a close relationship between gut microbiota and the anti-CRC effect of FOLFOX, though the underlying mechanisms remain unclear. Diet has been confirmed as a key factor influencing gut microbiota, and high-salt diets, representative of western dietary habits, has been shown to affect gut microbiota, immune function, and the risk of developing CRC. However, the impact of high-salt diets on the anti-CRC efficacy of FOLFOX remains unstudied. Therefore, we aimed to investigate the effect and mechanism of high-salt diets on the anti-CRC effect of FOLFOX.

METHODS

We performed 16 S rRNA sequencing and T500 targeted metabolomics analysis on fecal samples from CRC patients and healthy adults. A CRC orthotopic xenograft mouse model was used to study the effect of a high-salt diet on FOLFOX's anti-CRC efficacy. 16 S rRNA sequencing and non-targeted metabolomics were conducted on mouse fecal samples. Flow cytometry was used to assess immune cell infiltration in tumor and paracancerous tissues. A mouse macrophage conditioned medium system, with tryptophan metabolites, was employed to annotate the functional metabolites, followed by in vivo verification using the orthotopic xenograft mouse model.

RESULTS

The structure and metabolic profiles of gut microbiota are significantly different between 9 healthy adults and 6 CRC patients. A high-salt diet significantly reduced the efficacy of FOLFOX in mice, with notable changes in gut microbiota and related metabolites. Correlation analysis revealed a significant relationship between gut microbiota, tryptophan metabolites and FOLFOX efficacy. Flow cytometry indicated that a high-salt diet altered macrophage infiltration (CD45+F4/80+) in both the tumor and paracancerous tissues. In vitro experiments confirmed that the tryptophan metabolite SK reduced FOLFOX efficacy, while IPA enhanced it through macrophage-conditioned medium. In vivo, we verified that under a high-salt diet, SK inhibited the efficacy of FOLFOX, while IPA promoted it.

CONCLUSION

A high-salt diet reduces the anti-CRC efficacy of FOLFOX through gut bacterial tryptophan metabolism mediated macrophage immunomodulation.

Could Panitumumab with very low dose Capecitabine be an option as a maintenance regimen

BACKGROUND

Anti-epidermal growth factor receptor therapy showed an overall median survival improvement in wild type Ras metastatic colorectal cancer. Maintenance with anti EGFR in metastatic colorectal cancer wild type Ras was studied in many trials with promising results and many of these trials gave combined chemo with the target therapy and this combination had shown benefit in the form of synergistic effect and in delaying the resistance to the anti EGFR.

METHOD

In our study patients received 6 cycles of 5-FU based chemotherapy with Panitumumab and patients who had partial response, complete response or stationary disease received metronomic Capecitabine with Panitumumab every 2 weeks for one year. The primary end point was progression free survival (PFS) and the secondary end points were safety, toxicity and overall survival (OS).

RESULTS

The median PFS for all patients was 18 ± 1.4 months and the median OS was 45 months. Patients with synchronous metastasis and those who received Oxaliplatin based regimen with Panitumumab were found to have longer PFS compared to those with metachronous metastasis or those who received other chemotherapy regimen with accepted toxicity profile to the maintenance therapy.

CONCLUSION

Using Panitumumab with metronomic Capecitabine is considered an accepted maintenance regimen in wild type Ras metastatic colorectal cancer regardless of the primary site.

Surgical Management of Colorectal Cancer Liver Metastases

Approximately 50% of colorectal cancer patients develop liver metastases. Hepatic metastases represent the most common cause of colorectal cancer-related mortality. Metastasectomy, if possible, represents the most effective treatment strategy; 20% of patients will be cured and more than 50% survive at least 5 years. Nuances to treatment planning hinge on whether patients present with resectable disease upfront, whether the future liver remnant is adequate, and whether the primary tumor, if present, is colon versus rectal in origin. This article discusses considerations impacting our approach to patients with colorectal liver metastases and the role for various multimodal treatment options.

Factors Influencing the Duration of Maintenance Therapy in Metastatic Colorectal Cancer

BACKGROUND/OBJECTIVES

Metastatic colorectal cancer (mCRC) is mainly treated with 5-Fluoro-Uracil (5-FU), Oxaliplatin and Irinotecan chemotherapies and anti-Epidermal Growth Factor Receptor (EGFR) or anti-Vascular Endothelial Growth Factor (VEGF) targeted therapies. Due to chemotherapy-related toxicity, patients receive induction treatment to achieve tumour response followed by maintenance therapy with less cytotoxic molecules or a chemotherapy-free interval to reduce chemotherapy-related toxicity. In this study, the aim was to determine the patient, cancer and treatment factors that influence the duration of maintenance therapy (DMT).

METHODS

We collected retrospective data on a cohort of 133 patients treated at the Centre Georges François Leclerc (CGFL) cancer centre in Dijon between March 2014 and June 2022. Patients had unresectable or potentially resectable diseases. They received first-line induction treatment with chemotherapy and/or targeted therapy and maintenance treatment, defined as the interruption of at least one chemotherapy agent.

RESULTS

In the multivariate analysis, age (HR: 1.02, 95% CI 1.00-1.04, p = 0.031), N2 nodal status (HR: 1.78, 95% CI 1.09-2.89, p = 0.021) and the presence of peritoneal metastases (HR: 2.05, 95% CI 1.25-3.36, p = 0.004), as well as baseline carcino-embryonic antigen (CEA) level (HR: 1.10, 95% CI 1.00-1.20, p = 0.052), were significantly associated to poor DMT. Local treatment of liver metastases also significantly reduced the DMT (HR: 0.49, 95% CI 0.28-0.86, p = 0.013). In our cohort, induction triplet chemotherapy significantly increased the CEA delta (70% vs. 44%, p = 0.047) compared to doublet chemotherapy and led to a higher rate of liver surgery (40% vs. 21%, p = 0.014) and a trend for a higher rate of local treatment of metastases (62% vs. 45%, p = 0.059).

CONCLUSIONS

Duration of maintenance therapy is determined by the initial patient and colorectal cancer characteristics. However, it is significantly increased by local treatment of liver metastases. By reducing the tumour burden, a triplet induction chemotherapy regimen increases the rate of liver metastase resection.

More subtle microsatellite instability better predicts fluorouracil insensitivity in colorectal cancer patients

Microsatellite instability (MSI) is now widely used as an indispensable biomarker. However, the relationship between MSI-H (high) and defective DNA mismatch repair (MMR) is not as straightforward as has been expected. Genome-edited cells carrying Lynch syndrome mutations do not exhibit drastic MSI typical in MSI-H (i.e. Type B) but more subtle MSI (i.e. Type A). In this study, we explored a connection between Type A MSI and 5-fluorouracil (5-FU) resistance in colorectal cancer patients. Using our precision and high-resolution MSI assay technique, tumour microsatellites were analysed in 30 colorectal cancer patients treated with FOLFOX or CAPOX. Among 30 tumours, eleven (37%) were judged as Type A MSI-positive. In Type A MSI+ tumours, the patient response to fluoropyrimidine and oxaliplatin was significantly poor (Fisher's exact test, p = 0.021). Accordingly, median PFS and OS were significantly poor in Type A+ patients (log-rank test, p < 0.001/p = 0.009). Type A MSI was an independent predictor of patient prognosis in this pilot cohort (Cox regression analysis, p = 0.003). Thus, more subtle Type A MSI better predicts fluoropyrimidine insensitivity in colorectal cancer patients, which may shed light on a hitherto overlooked connection between the MSI phenotypes and drug resistance in human cancer.

First-Line Therapy in Metastatic, RAS Wild-Type, Left-Sided Colorectal Cancer: Should Everyone Receive Anti-EGFR Therapy?

PURPOSE OF REVIEW

This narrative review explores the efficacy and applicability of anti-EGFR therapy as the first-line treatment for patients with RAS wild-type (WT) left-sided metastatic colorectal cancer (mCRC). It critically examines current guidelines, along with recent evidence in the literature, to assess whether it should be universally applied.

RECENT FINDINGS

Recent evidences highlight the variability of the response to anti-EGFR therapies due to molecular diversity and several clinical factors, such as RAS mutational status and primary tumor location. Anti-EGFR plus chemotherapy is the standard first-line treatment for most patients with MSS, RAS-WT, left-sided mCRC. Whether this combination is the best treatment for these patients remains an open question. This review delves into the role of EGFR inhibition in mCRC, focusing on clinical factors and the knowledge of biology, molecular targets, and biomarkers. It underscores the crucial role of a personalized approach, empowering healthcare providers and equipping them with the confidence to make informed decisions.

Signaling pathways involved in colorectal cancer: pathogenesis and targeted therapy

Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide. Its complexity is influenced by various signal transduction networks that govern cellular proliferation, survival, differentiation, and apoptosis. The pathogenesis of CRC is a testament to the dysregulation of these signaling cascades, which culminates in the malignant transformation of colonic epithelium. This review aims to dissect the foundational signaling mechanisms implicated in CRC, to elucidate the generalized principles underpinning neoplastic evolution and progression. We discuss the molecular hallmarks of CRC, including the genomic, epigenomic and microbial features of CRC to highlight the role of signal transduction in the orchestration of the tumorigenic process. Concurrently, we review the advent of targeted and immune therapies in CRC, assessing their impact on the current clinical landscape. The development of these therapies has been informed by a deepening understanding of oncogenic signaling, leading to the identification of key nodes within these networks that can be exploited pharmacologically. Furthermore, we explore the potential of integrating AI to enhance the precision of therapeutic targeting and patient stratification, emphasizing their role in personalized medicine. In summary, our review captures the dynamic interplay between aberrant signaling in CRC pathogenesis and the concerted efforts to counteract these changes through targeted therapeutic strategies, ultimately aiming to pave the way for improved prognosis and personalized treatment modalities in colorectal cancer.

Management of Metastatic Colorectal Cancer (mCRC): Real-World Recommendations

INTRODUCTION

Metastatic CRC is considered as a heterogenous disease. Its management is therefore complex and dynamic. In order the give a ready reference to community oncologists, we developed this real world recommendations.

METHODS

A group of experts with academic background and real world experience in mCRC got together. We reviewed the current literature and the insights gained from our real world experience. Based on the same we put together these recommendations.

RECOMMENDATIONS RESULTS

Molecular testing should be done wherever possible. Most of these patients will be treated with a palliative approach. Doublet chemotherapy is a long-standing standard of care. Triplet therapy may be offered where a more aggressive approach is indicated. Combination with anti -vascular endothelial growth factor antibodies and/or anti EGFR antibodies is also considered standard. In the first-line setting, pembrolizumab can be used for patients with mCRC and microsatellite instability-high or deficient mismatch repair tumours; Left and right sided tumours are distinct entities. Combination of chemotherapy and targeted therapy is used as per individual patient and tumour characteristics.Oligometastatic disease can be approached with potentially curative intent. Cytoreductive surgery plus chemotherapy can be offered to selected patients with peritoneal only metastases. Stereotactic body radiation therapy can be used as local therapy for patients with oligometastatic liver only disease who cannot be taken up for surgery. New strategies include induction-maintenance chemotherapy and perioperative chemotherapy. All drugs/ regimen included as standard of care in the first line can also be used in subsequent lines. Specific targetable driver mutation tumours can be treated accordingly with their complementary biological therapy.

CONCLUSION

Multidisciplinary team management and shared decision making are possible when patient and caregivers choose to become active participants.

MCT1-dependent lactate recycling is a metabolic vulnerability in colorectal cancer cells upon acquired resistance to anti-EGFR targeted therapy

Despite the implementation of personalized medicine, patients with metastatic CRC (mCRC) still have a dismal overall survival due to the frequent occurrence of acquired resistance mechanisms thereby leading to clinical relapse. Understanding molecular mechanisms that support acquired resistance to anti-EGFR targeted therapy in mCRC is therefore clinically relevant and key to improving patient outcomes. Here, we observe distinct metabolic changes between cetuximab-resistant CRC cell populations, with in particular an increased glycolytic activity in KRAS-mutant cetuximab-resistant CRC cells (LIM1215 and OXCO2) but not in KRAS-amplified resistant DiFi cells. We show that cetuximab-resistant LIM1215 and OXCO2 cells have the capacity to recycle glycolysis-derived lactate to sustain their growth capacity. This is associated with an upregulation of the lactate importer MCT1 at both transcript and protein levels. Pharmacological inhibition of MCT1, with AR-C155858, reduces the uptake and oxidation of lactate and impairs growth capacity in cetuximab-resistant LIM1215 cells both in vitro and in vivo. This study identifies MCT1-dependent lactate utilization as a clinically actionable, metabolic vulnerability to overcome KRAS-mutant-mediated acquired resistance to anti-EGFR therapy in CRC.

Prognostic value of liver metastases in colorectal cancer treated by systemic therapy: An ARCAD pooled analysis

BACKGROUND

The liver is the most frequent site of metastases in colorectal cancer (CRC). This study aimed to assess the response rate and survival outcomes in metastatic CRC patients with non-liver metastases (NLM) compared to those with liver metastases (LM) across different lines of treatment.

METHODS

A total of 17,924 mCRC patients included in 26 trials from the ARCAD CRC database were analyzed. The analysis was conducted based on the presence or absence of LM across different treatment groups: chemotherapy (CT) alone, CT + anti-VEGF, CT + anti-EGFR in KRAS wild-type tumors, within the first-line (1 L) and second-line (2 L), and patients enrolled in third-line (≥3 L) trials treated with trifluridine/tipiracil or regorafenib or placebo. The endpoints were overall survival (OS), progression-free survival (PFS), and overall response rate (ORR).

RESULTS

Out of the 17,924 patients, 14,066 had LM (30.6 % with only liver involvement and 69.4 % with liver and other metastatic sites), while 3858 patients had NLM. In the CT alone and CT + anti-VEGF subgroups, NLM patients showed better OS and PFS in the 1 L and 2 L settings. However, in the CT + anti-EGFR 1 L and 2 L subgroups, there was no significant difference in OS and PFS between NLM and LM patients. In the ≥ 3 L subgroups, better OS and PFS were observed in NLM patients. ORRs were higher in LM patients than in NLM patients across all cohorts treated in the 1 L and only in the anti-EGFR cohort in the 2 L.

CONCLUSION

LM is a poor prognostic factor for mCRC increasing from 1 L to ≥ 3 L except for patients in 1 L and 2 L receiving CT+anti-EGFR. These data justify using LM as a stratification factor in future trials for patients with unresectable mCRC.

Evolution and current trends in the management of colorectal cancer liver metastasis

Metastatic colorectal cancer (mCRC) is a major cause of cancer-related death, with a 5-year relative overall survival of up to 20%. The liver is the most common site of distant metastasis in colorectal cancer (CRC), with about 50% of CRC patients metastasizing to their liver over the course of their disease. Complete liver resection is the primary modality of treatment for resectable colorectal cancer liver metastasis (CRLM), with an overall 5-year survival rate of up to 58%. However, only 15% to 20% of patients with CRLM are deemed suitable for resection at presentation. For unresectable diseases, the median survival of patients remains low even with the best chemotherapy. In recent decades, the management of CRLM has continued to evolve with the expansion of resection criteria, novel targeted systemic therapies, and improved locoregional therapies. However, due to the heterogeneity of the CRC patient population, the optimal evaluation of treatment options for CRLM remains complex. Therefore, effective management requires a multidisciplinary team to help define resectability and devise a personalized treatment approach, from the initial diagnosis to the final treatment.

Trends in patterns of treatment and survival of colorectal cancer patients using cancer registry data in Japan: 1995-2015

Recent advances in treating colorectal cancer (CRC) have increased the importance of multidisciplinary treatment. This study aimed to clarify trends in the treatment and survival of CRC using population-based cancer registry data in Japan. We analyzed the survival of CRC cases diagnosed from 1995 through 2015 from a population-based cancer registry of six prefectures. The year of diagnosis was classified into five periods, and the trends in the detailed categorization of treatments and survival were identified. We calculated net survival and excess hazard of death from cancer using data on 256,590 CRC patients. The use of laparoscopic surgery has been increasing since 2005 and accounts for the largest proportion of treatment types in the most recent period. Net survival of CRC patients diagnosed after 2005 remained high for laparoscopic surgery and endoscopic surgery (endoscopic mucosal resection or endoscopic submucosal dissection). There was an upward trend in treatment with chemotherapy in addition to open and laparoscopic surgery. Using the excess hazard ratio at the regional stage since 2005, there has been a significant improvement in survival in the younger age group and the rectum cancer group. By type of treatment, there was a tendency toward significant improvement in the open surgery + chemotherapy group. We clarified the trends in treating CRC and the associated trends in survival. Continuous survey based on population-based data helps monitor the impact of developments in treatment.

Safety of first-line systemic therapy in patients with metastatic colorectal cancer: a network meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the safety of first-line systemic therapy for metastatic colorectal cancer through network meta-analysis.

METHODS

The literature from PubMed, Embase, Web of Science, and Cochrane Library databases was searched from the inception of the databases to August 15, 2023, and strict inclusion and exclusion criteria were applied to screen studies. The Cochrane Bias Risk Assessment Tool (RoB 2.0) was used to evaluate the quality of the included literature. Network meta-analysis was conducted using Stata 15.0 and R4.3.1 software to compare the incidence of adverse events (AEs) among different treatment regimens.

RESULTS

A total of 53 randomized controlled trials, involving 17,351 patients with metastatic colorectal cancer (mCRC), were ultimately included, encompassing 29 different therapeutic approaches. According to SUCRA rankings, the CAPOX regimen is most likely to rank first in terms of safety, while the FOLFOXIRI + panitumumab regimen is most likely to rank last. In terms of specific AEs, the CAPOX regimen, whether used alone or in combination with targeted drugs (bevacizumab and cetuximab), is associated with a reduced risk of neutropenia and febrile neutropenia, as well as an increased risk of thrombocytopenia and diarrhea. The FOLFOX regimen, with or without bevacizumab, is linked to an increased risk of neutropenia and peripheral sensory neuropathy. The FOLFIRI/CAPIRI + bevacizumab regimen is associated with a reduced risk of peripheral sensory neuropathy. S-1 and S-1 + oxaliplatin are well-tolerated in terms of gastrointestinal reactions. The FOLFOXIRI regimen, whether used alone or in combination with targeted drugs, is associated with various AEs.

CONCLUSION

In summary, the CAPOX regimen may be the safest option among the first-line systemic treatment regimens for mCRC patients, while the FOLFOXIRI + panitumumab regimen may be associated with a higher incidence of grade 3 or higher AEs.

Tumor-Agnostic Therapy-The Final Step Forward in the Cure for Human Neoplasms?

Cancer accounted for 10 million deaths in 2020, nearly one in every six deaths annually. Despite advancements, the contemporary clinical management of human neoplasms faces a number of challenges. Surgical removal of tumor tissues is often not possible technically, while radiation and chemotherapy pose the risk of damaging healthy cells, tissues, and organs, presenting complex clinical challenges. These require a paradigm shift in developing new therapeutic modalities moving towards a more personalized and targeted approach. The tumor-agnostic philosophy, one of these new modalities, focuses on characteristic molecular signatures of transformed cells independently of their traditional histopathological classification. These include commonly occurring DNA aberrations in cancer cells, shared metabolic features of their homeostasis or immune evasion measures of the tumor tissues. The first dedicated, FDA-approved tumor-agnostic agent's profound progression-free survival of 78% in mismatch repair-deficient colorectal cancer paved the way for the accelerated FDA approvals of novel tumor-agnostic therapeutic compounds. Here, we review the historical background, current status, and future perspectives of this new era of clinical oncology.

Genome-wide DNA methylation status is a predictor of the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer: Translational research of the EPIC trial

PURPOSE

The genome-wide DNA methylation status (GWMS) predicts of therapeutic response to anti-epidermal growth factor receptor (EGFR) antibodies in treating metastatic colorectal cancer. We verified the significance of GWMS as a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer.

METHODS

Clinical data were obtained from a prospective trial database, and a genome-wide DNA methylation analysis was performed. GWMS was classified into high-methylated colorectal cancer (HMCC) and low-methylated colorectal cancer (LMCC). The patients were divided into subgroups according to the treatment arm (cetuximab plus irinotecan or irinotecan alone) and GWMS, and the clinical outcomes were compared between the subgroups.

RESULTS

Of the 112 patients, 58 (51.8%) were in the cetuximab plus irinotecan arm, and 54 (48.2%) were in the irinotecan arm; 47 (42.0%) were in the HMCC, and 65 (58.0%) were in the LMCC group regarding GWMS. Compared with the LMCC group, the progression-free survival (PFS) was significantly shortened in the HMCC group in the cetuximab plus irinotecan arm (median 1.4 vs. 4.1 months, p = 0.001, hazard ratio = 2.56), whereas no significant differences were observed in the irinotecan arm. A multivariate analysis showed that GWMS was an independent predictor of PFS and overall survival (OS) in the cetuximab plus irinotecan arm (p = 0.002, p = 0.005, respectively), whereas GWMS did not contribute to either PFS or OS in the irinotecan arm.

CONCLUSIONS

GWMS was a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer.

Epidermal growth factor receptor antagonists in colorectal cancer: emerging strategies for precision therapy

INTRODUCTION

The global prevalence of colorectal cancer highlights the need to enhance treatment strategies for improved patient outcomes. The pivotal role of epidermal growth factor receptor (EGFR) signaling in regulating cellular processes for this disease pinpoints its value as a therapeutic target, despite the emergence of resistance mechanisms over time.

AREAS COVERED

This review discusses the clinical evidence supporting the use of EGFR inhibitors in molecularly-selected patients based on molecular characteristics (notably BRAF V600E and KRAS G12C) including combination approaches targeting different points in in the signaling pathway, as well as strategies such as EGFR inhibitor rechallenge. The role of HER2 inhibitors and emerging approaches such as bispecific antibodies are also reviewed.

EXPERT OPINION

Recently, inhibitors targeting the KRAS G12C variant have emerged, albeit with modest monotherapy activity compared to other tumor types, emphasizing the influence of histologic origins on the EGFR signaling pathway. Integration of EGFR inhibitors into precision medicine has facilitated tailored therapies addressing resistance mechanisms. Patient selection for EGFR inhibitor rechallenge guided by ctDNA findings is crucial, with ongoing investigations exploring novel combinations to enhance EGFR blockade, highlighting the transformative potential of precision medicine in shaping the future of mCRC treatment toward personalized and targeted approaches.

CircHIF1A induces cetuximab resistance in colorectal cancer by promoting HIF1α-mediated glycometabolism alteration

Epidermal growth factor receptor (EGFR)-targeted therapy is an important treatment for RAS wild-type metastatic colorectal cancer (mCRC), but the resistance mechanism remains unclear. Here, the differential expression of circRNAs between Cetuximab sensitive and resistant cell lines was analyzed using whole-transcriptome sequencing. We identified that the expression of circHIF1A was significantly higher in LIM1215-R than in LIM1215. When treated with Cetuximab, downregulation of circHIF1A level weakened the proliferation and clonal formation ability of LIM1215-R, caused more cells to enter G0-G1 phase, and significantly reduced the basal respiration, ATP production, and maximal respiration, as well as the glycolytic capacity and glycolytic reserve. The response rate and prognosis of circHIF1A-positive patients were inferior to those of negative patients. Mechanistically, circHIF1A can upregulate the level of hypoxia-inducible factor 1 A (HIF1A) by competitively binding to miR-361-5p, inducing the overexpression of enzymes such as glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA). In a xenograft model, inhibition of circHIF1A expression increased the sensitivity to Cetuximab treatment. In conclusion, circHIF1A can promote HIF1α-mediated glycometabolism alteration to induce Cetuximab resistance in CRC. It has the potential to become a screening indicator for the Cetuximab beneficial population in mCRC and a new therapeutic target for enhancing treatment efficacy.

Unveiling acquired resistance to anti-EGFR therapies in colorectal cancer: a long and winding road

Emergence of acquired resistance limits the efficacy of the anti-EGFR therapies cetuximab and panitumumab in metastatic colorectal cancer. In the last decade, preclinical and clinical cohort studies have uncovered genomic alterations that confer a selective advantage to tumor cells under EGFR blockade, mainly downstream re-activation of RAS-MEK signaling and mutations in the extracellular domain of EGFR (EGFR-ECD). Liquid biopsies (genotyping of ctDNA) have been established as an excellent tool to easily monitor the dynamics of genomic alterations resistance in the blood of patients and to select patients for rechallenge with anti-EGFR therapies. Accordingly, several clinical trials have shown clinical benefit of rechallenge with anti-EGFR therapy in genomically-selected patients using ctDNA. However, alternative mechanisms underpinning resistance beyond genomics -mainly related to the tumor microenvironment-have been unveiled, specifically relevant in patients receiving chemotherapy-based multi-drug treatment in first line. This review explores the complexity of the multifaceted mechanisms that mediate secondary resistance to anti-EGFR therapies and potential therapeutic strategies to circumvent acquired resistance.

FOLFOXIRI plus cetuximab as conversion therapy for unresectable RAS/BRAF wild-type left-sided colorectal cancer with liver-limited metastases: a prospective dual-center pilot study

Purpose

To explore the efficacy and safety of FOLFOXIRI plus cetuximab regimen as conversion therapy for patients with unresectable RAS/BRAF wild-type colorectal liver-limited metastases (CLM).

Patients and methods

This was a dual-center, phase II trial with the rate of no evidence of disease (NED) achieved as the primary endpoint. All enrolled patients with initially unresectable left-sided RAS/BRAF wild-type colorectal liver-limited metastases received a modified FOLFOXIRI plus cetuximab regimen as conversion therapy.

Results

Between October 2019 and October 2021, fifteen patients were enrolled. Nine patients (60%) achieved NED. The overall response rate (ORR) was 92.9%, and the disease control rate (DCR) was 100%. The median relapse-free survival (RFS) was 9 (95% CI: 0-20.7) months. The median progression-free survival (PFS) was 13.0 months (95% CI: 5.7-20.5), and the median overall survival (OS) was not reached. The most frequently occurring grade 3-4 adverse events were neutropenia (20%), peripheral neurotoxicity (13.3%), diarrhea (6.7%), and rash acneiform (6.7%).

Conclusion

The FOLFOXIRI plus cetuximab regimen displayed tolerable toxicity and promising anti-tumor activity in terms of the rate of NED achieved and response rate in patients with initially unresectable left-sided RAS/BRAF wild-type CLM. This regimen merits further investigation.

Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients' values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Combined Resection Approaches: Decision Making for Synchronous Resection, Timing of Staged Intervention to Optimize Outcome

Advancement in systemic and regional radiation therapy, surgical technique, and anesthesia has provided a path for increased long-term survival and potential cure for more patients with stage IV rectal cancer in recent years. When patients have resectable disease, the sequence for surgical resection is classified in three strategies: classic, simultaneous, or combined, and reversed. The classic approach consists of rectal cancer resection followed by metastatic disease at a subsequent operation. Simultaneous resection addresses both rectal and metastatic disease in a single surgery. The reversed approach treats metastatic disease first, followed by the primary tumor in several months. Simultaneous resection is appropriate for selected patients to avoid delay of definitive surgery, and reduce number of surgeries, hospital stay, and cost to the health care system. It may also improve patients' psychological effect. Multidisciplinary discussions including colorectal and liver surgeons to review patients' baseline medical conditions, tumor biology and behavior, and disease burden and distribution is imperative to guide proper patient selection for simultaneous resection and perioperative treatments.

Modified FOLFOX6 with Cetuximab versus with Radiotherapy in Neoadjuvant Treatment of Locally Advanced Rectal Cancer: A Single-Center, Prospective, Randomized Controlled Trial

In this trial, the feasibility and efficacy of neoadjuvant chemotherapy with targeted agents in the treatment of patients with locally advanced rectal cancer were evaluated. In this single-center, prospective, randomized controlled trial, we randomly assigned (1 : 1) patients with locally advanced rectal cancer with wild-type RAS/BRAF gene to two groups: 5 cycles of modified leucovorin calcium (folinic acid), fluorouracil, and oxaliplatin combination regimen (modified FOLFOX6, mFOLFOX6) concurrent with 25 times radiotherapy or 5 cycles of mFOLFOX6 plus cetuximab, all with subsequent total mesorectal excision (TME) resection and adjuvant chemotherapy. We performed a random assignment by a computer-generated random number sequence. The primary end point was the R0 resection rate. The secondary end points were rates of pathologic complete response, downstaging, adverse events, postoperative complications, preventive enterostomy and low anterior resection syndrome. From January 6, 2020 to October 28, 2022, 80 patients were assigned and evaluated. In the mFOLFOX6-RT and mFOLFOX6-Cet groups, the rate of R0 resection was 96.7 and 96.9% (p = 1.000); the rate of pathological complete response (pCR) was 23.3 and 21.9% (p = 0.891); and the rate of downstaging (ypStage 0 to 1) was 53.3 and 53.1% (p = 1.000), respectively. No statistical differences between the two groups were observed in the incidence of adverse events and postoperative complications. Additionally, lower rates of preventive enterostomy and low anterior resection syndrome were shown in the mFOLFOX6-Cet group compared to the mFOLFOX6-RT group. The neoadjuvant treatment strategy of mFOLFOX6 with cetuximab is feasible and promising for patients with locally advanced rectal cancer, even superior to mFOLFOX6 with radiotherapy.

Gastrointestinal Malignancy: Genetic Implications to Clinical Applications

Advances in molecular genetics have revolutionized our understanding of the pathogenesis, progression, and therapeutic options for treating gastrointestinal (GI) cancers. This chapter provides a comprehensive overview of the molecular landscape of GI cancers, focusing on key genetic alterations implicated in tumorigenesis across various anatomical sites including GIST, colon and rectum, and pancreas. Emphasis is placed on critical oncogenic pathways, such as mutations in tumor suppressor genes, oncogenes, chromosomal instability, microsatellite instability, and epigenetic modifications. The role of molecular biomarkers in predicting prognosis, guiding treatment decisions, and monitoring therapeutic response is discussed, highlighting the integration of genomic profiling into clinical practice. Finally, we address the evolving landscape of precision oncology in GI cancers, considering targeted therapies and immunotherapies.

An update on pharmacotherapies for colorectal cancer: 2023 and beyond

INTRODUCTION

Colorectal cancer (CRC) is one of the most prevalent and lethal cancers worldwide. The treatment of metastatic colorectal cancer (mCRC) is difficult, and mCRC has a survival rate of only 13-17% compared with 70-90% in locoregional CRC. There is ongoing research effort on pharmacotherapy for CRC to improve the treatment outcome.

AREAS COVERED

We reviewed the current literature and ongoing clinical trials on CRC pharmacotherapy, with a focus on targeted therapy based on the results of genetic testing. The pharmacotherapies covered in this article include novel agents targeting EGFR and EGFR-related pathways, agents targeting the VEGF pathway, immunotherapy options depending on the MMR/MSI status, and new therapies targeting genetic fusions such as NTRK. We also briefly discuss the value of next-generation sequencing (NGS) in treatment selection and response monitoring.

EXPERT OPINION

We advocate for the early and routine use of NGS to genetically characterize CRC to assist with pharmacotherapy selection. Targeted therapy is a promising field of ongoing research and improves CRC treatment outcome.

Selecting Optimal First-Line Treatment for Microsatellite Stable and Non-Mutated RAS/BRAF Metastatic Colorectal Cancer

OPINION STATEMENT

Standard frontline treatment of metastatic colorectal cancer (CRC) is cytotoxic chemotherapy plus a biologic agent such as an anti-EGFR monoclonal antibody (cetuximab or panitumumab) or anti-VEGF antibody (bevacizumab). Predictive biomarkers include mismatch repair (MMR) status, and RAS and BRAF mutation status; and important factors in treatment selection include primary tumor location, intent of therapy, and potential toxicity, as well as patient age, comorbidities, and patient preference. To date, single-, double-, or triple-agent cytotoxic chemotherapy all have important roles in appropriately selected patients, with the addition of anti-VEGF or anti-EGFR antibody therapy based on the relevant predictive biomarker. Data indicate that patients with proficient MMR, RAS/BRAF wt mCRC are candidates for an anti-EGFR antibody plus doublet chemotherapy if they have a left-sided primary tumor, or for anti-VEGF (bevacizumab) plus doublet or triplet chemotherapy if they have a right-sided primary tumor. Future studies may provide more predictive biomarkers to further personalize therapy for this heterogeneous disease.

Prospective, open-label, and observational study of cetuximab for metastatic colorectal carcinoma: The OPTIM1SE study

AIM

The OPTIM1SE study observed long-term real-world outcomes of cetuximab-based infusional 5-fluorouracil (5-FU) regimens for first-line treatment of metastatic colorectal cancer (mCRC) across Asia-Pacific and Middle East regions, aiming to characterize their use, effectiveness, and safety in routine practice.

METHODS

OPTIM1SE was a prospective, open-label, observational study. Patients with untreated KRAS wild-type mCRC and distant metastases were treated per locally approved labels and monitored for 3 years via electronic medical records. The primary endpoint was the overall response rate (ORR). Secondary endpoints included safety, progression-free survival (PFS), and overall survival (OS).

RESULTS

From November 19, 2013, to June 30, 2016, 520 patients were enrolled in 51 sites. Patients were mostly male (61.2%), with a mean age of 58.5 (±12.0) years; 420 patients received leucovorin, 5-FU, and irinotecan-based regimens and 94 received leucovorin, 5-FU, and oxaliplatin. The most common primary tumor site was the rectum (38.8%), with liver metastases (65.0%). ORR was 45.4% (95% CI, 41.1%-49.7%), including 26 patients (5.0%) with a complete response. Median PFS was 9.9 months (95% CI, 8.2-11.0); median OS (mOS) was 30.8 months (95% CI, 27.9-33.6). Higher mOS was associated with tumors of left compared with right-sided origin (hazard ratio, 0.69 [95% CI, 0.49-0.99]); higher ORR was also associated with liver metastases compared with all other metastases (55.4% vs. 40.2%). Adverse events were consistent with the known safety profile of cetuximab.

CONCLUSION

Cetuximab-based 5-FU regimens were effective first-line treatments for mCRC in routine practice, particularly in patients with left-sided disease and liver metastases only.

Clinical outcomes of intensive versus less intensive first-line chemotherapy for metastatic colorectal cancer

Aims: Physicians determine the treatment regimen for metastatic colorectal cancer on a case-by-case bases, according to the individual disease characteristics. We retrospectively compared the baseline characteristics and efficacies of first-line treatment among patients with metastatic colorectal cancer who received intensive therapy involving fluoropyrimidine plus oxaliplatin and/or irinotecan, potentially with molecularly targeted agents as well, versus less intensive fluoropyrimidine and/or bevacizumab therapy. Materials & methods: Data were collected from a medical claims database. The efficacy outcomes were: time to treatment failure, time to first subsequent therapy and overall survival. Results: The less intensive therapy group (n = 633) had higher median age, lower daily activity levels and shorter time to treatment failure, time to first subsequent therapy and overall survival than the intensive therapy group (n = 3829). Combination therapy with molecularly targeted agents and bevacizumab improved treatment efficacy outcomes in the intensive and less intensive groups, respectively. Conclusion: Patient age and daily activity levels were important factors for determining treatment intensity.

Construction of a prognostic model for colorectal adenocarcinoma based on Zn transport-related genes identified by single-cell sequencing and weighted co-expression network analysis

Background

Colorectal cancer (CRC) is one of the most prevalent malignancies and the third most lethal cancer globally. The most reported histological subtype of CRC is colon adenocarcinoma (COAD). The zinc transport pathway is critically involved in various tumors, and its anti-tumor effect may be through improving immune function. However, the Zn transport pathway in COAD has not been reported.

Methods

The determination of Zn transport-related genes in COAD was carried out through single-cell analysis of the GSE 161277 obtained from the GEO dataset. Subsequently, a weighted co-expression network analysis of the TCGA cohort was performed. Then, the prognostic model was conducted utilizing univariate Cox regression and least absolute shrinkage and selection operator (LASSO) Cox regression analysis. Functional enrichment, immune microenvironment, and survival analyses were also carried out. Consensus clustering analysis was utilized to verify the validity of the prognostic model and explore the immune microenvironment. Ultimately, cell experiments, including CCK-8,transwell and scratch assays, were performed to identify the function of LRRC59 in COAD.

Results

According to the Zn transport-related prognostic model, the individuals with COAD in TCGA and GEO databases were classified into high- and low-risk groups. The group with low risk had a comparatively more favorable prognosis. Two groups had significant variations in the immune infiltration, MHC, and the expression of genes related to the immune checkpoint. The cell experiments indicated that the proliferation, migration, and invasion of the HCT-116, DLD-1, and RKO cell lines were considerably increased after LRRC59 knockdown. It proved that LRRC59 was indeed a protective factor for COAD.

Conclusion

A prognostic model for COAD was developed using zinc transport-related genes. This model can efficiently assess the immune microenvironment and prognosis of individuals with COAD. Subsequently, the function of LRRC59 in COAD was validated via cell experiments, highlighting its potential as a biomarker.

Real-World Outcomes in Patients with Metastatic Colorectal Cancer in Spain: The RWD-ACROSS Study

The retrospective, observational RWD-ACROSS study analyzed disease characteristics, systemic treatment, and survival in patients with metastatic colorectal cancer (mCRC) in Spain. In total, 2002 patients were enrolled (mean age 65.3 years; 62.7% male). Overall median overall survival (OS) was 26.72 months, and was longer in patients with left-sided tumors (28.85 vs. 21.04 months (right-sided tumors); p < 0.0001) and in patients receiving first-line anti-epidermal growth factor receptor (EGFR) treatment (31.21 vs. 26.75 (anti-vascular endothelial growth factor (VEGF) treatment) and 24.45 months (chemotherapy); p = 0.002). Overall median progression-free survival (PFS) was 10.72 months and was longer in patients with left-sided tumors (11.24 vs. 9.31 months (right-sided tumors); p < 0.0001), and in patients receiving either first-line anti-EGFR or anti-VEGF (12.13 and 12.00 vs. 8.98 months (chemotherapy); p < 0.001). PFS was longer with anti-VEGF treatment in patients with right-sided tumors and wild-type RAS (11.24 vs. 8.78 (anti-EGFR) and 7.83 months (chemotherapy); p = 0.025). Both anti-EGFR and anti-VEGF produced longer PFS in patients with left-sided tumors and wild-type RAS than chemotherapy alone (12.39 and 13.14 vs. 9.83 months; p = 0.011). In patients with left-sided tumors and mutant RAS, anti-VEGF produced a longer PFS than chemotherapy alone (12.36 vs. 9.34 months; p = 0.001). In Spain, wild-type RAS or left-sided mCRC tumors are predictive of longer survival times.

Early-Onset Colon Cancer: A Narrative Review of Its Pathogenesis, Clinical Presentation, Treatment, and Prognosis

Colon cancer remains a leading cause of cancer-related deaths, and there has been a rise in the incidence of early-onset colon cancer or colon cancer diagnosed before the age of 50 years old. Early-onset colon cancer has several differences in clinical presentation, as well as histopathology, genetic alteration, and molecular profiling. Early-onset colon cancer can be differentiated into familial type that includes hereditary familial syndrome and sporadic type. Demographic variance also exists in both developing and developed countries. Due to the rising incidence of colon cancer diagnosed in younger age, it is imperative to examine the available evidence regarding the mortality rate of early-onset colon cancer. Colon cancer is affected by numerous modifiable and non-modifiable risk factors. Increasing obesity and lifestyle disorders in the younger population, such as smoking, may influence this increasing trend. There are existing guidelines for colon cancer screening in both average-risk and high-risk individuals. This narrative review aims to highlight the pathogenesis of early-onset CRC; its clinical presentation, treatment, prognosis; and how it differs from late-onset CRC.

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

Background

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

Methods

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

Results

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

Conclusions

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

Cetuximab as first-line treatment for metastatic colorectal cancer (mCRC): a model-based economic evaluation in Indonesia setting

OBJECTIVES

To assess the cost-effectiveness of cetuximab in combination with chemotherapy fluorouracil, oxaliplatin, and leucovorin (FOLFOX) or fluorouracil, irinotecan and leucovorin (FOLFIRI) compared to standard chemotherapy alone as a first-line treatment for metastatic colorectal cancer (mCRC) with positive KRAS wild type patients in Indonesia.

METHODS

A cost-utility analysis applying Markov model was constructed, with a societal perspective. Clinical evidence was derived from published clinical trials. Direct medical costs were gathered from hospital billings. Meanwhile, direct non-medical costs, indirect costs, and utility data were collected by directly interviewing patients. We applied 3% discount rate for both costs and outcomes. Probabilistic sensitivity analysis was performed to explore the model's uncertainty. Additionally, using payer perspective, budget impact analysis was estimated to project the financial impact of treatment coverage.

RESULTS

There was no significant difference in life years gained (LYG) between cetuximab plus FOLFOX/FOLFIRI and chemotherapy alone. The incremental QALY was only one month, and the incremental cost-effectiveness ratio (ICER) was approximately IDR 3 billion/QALY for cetuximab plus chemotherapy. Using 1-3 GDP per capita (IDR 215 million or USD 14,350) as the current threshold, the cetuximab plus chemotherapy was not cost-effective. The budget impact analysis resulted that if cetuximab plus chemotherapy remain included in the benefits package under the Indonesian national health insurance (NHI) system, the payer would need more than IDR 1 trillion for five years.

CONCLUSIONS

The combination of cetuximab and chemotherapy for mCRC is unlikely cost-effective and has a substantial financial impact on the system.

Enhanced Clinical Utility of Molecular Budding Signature as a Recurrence Risk Determinant in Stage II and III Colon Cancer Patients

BACKGROUND

A molecular budding signature (MBS), which consists of seven tumor budding-related genes, was recently presented as a prominent prognostic indicator in colon cancer (CC) using microarray data acquired from frozen specimens. This study aimed to confirm the predictive power of MBS for recurrence risk based on formalin-fixed, paraffin-embedded (FFPE) materials.

METHODS

This research utilized the same microarray data from a prior multicenter study using FFPE whole tissue sections, which retrospectively reviewed 232 stage II CC patients without adjuvant chemotherapy and 302 stage III CC patients with adjuvant chemotherapy. All patients underwent upfront curative surgery without neoadjuvant therapy between 2009 and 2012. An MBS score was calculated using the mean of log2 [each signal] of seven genes (MSLN, SLC4A11, WNT11, SCEL, RUNX2, MGAT3, and FOXC1) as described before.

RESULTS

The MBS-low group exhibited a better relapse-free survival (RFS) than the MBS-high group in stage II (P = 0.0077) and in stage III CC patients (P = 0.0003). Multivariate analyses revealed that the MBS score was an independent prognostic factor in both stage II (P = 0.0257) and stage III patients (P = 0.0022). Especially among T4, N2, or both (high-risk) stage III patients, the MBS-low group demonstrated markedly better RFS compared with the MBS-high group (P = 0.0013).

CONCLUSIONS

This study confirmed the predictive power of the MBS for recurrence risk by employing FFPE materials in stage II/III CC patients.

Strategic Insight into the Combination Therapies for Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the second most common cause of cancer-related deaths worldwide. The 5-year survival rate after curative resection is almost 80%, however, it is still less than satisfactory for metastatic CRC (mCRC). The combination approach including surgery, chemotherapy, molecular targeted therapy, and immunotherapy is a promising strategy due to its synergistic anticancer effect. Moreover, circulating tumor DNA (ctDNA) analysis has been reported to stratify the post-operative risk of recurrence, thus providing clinically valuable information for deciding to conduct adjuvant chemotherapy. Furthermore, multiple new drugs that potentially target undruggable genes, including KRAS, have been developed. In this review, we discuss the current management of patients with mCRC and future perspectives in the light of a combination therapeutic strategy.

A multi-institutional observational study evaluating the incidence and the clinicopathological characteristics of NeoRAS wild-type metastatic colorectal cancer

PURPOSE

As circulating tumor DNA (ctDNA) measurement becomes more widespread, the "NeoRAS" phenomenon, where tissue rat sarcoma viral oncogene homolog (RAS) status converts from mutant (MT) to wild-type (WT) after treatment in metastatic colorectal cancer (mCRC), is gaining attention because ineffective epidermal growth factor receptor (EGFR) inhibitors may made effective. This study investigated its incidence and clinicopathological characteristics.

PATIENTS AND METHODS

In total, 107 mCRC patients (refractory or intolerant to previous chemotherapies) with tissue RAS MT were enrolled in four institutions from June 2021 to August 2022. The RAS status in ctDNA was assessed using OncoBEAM™ RAS CRC assay. Clinicopathologic features were compared between patients according to their RAS status in ctDNA, whether WT conversion was noted or not.

RESULTS

The incidence rate of NeoRAS WT mCRC was 21.5% (23/107). According to tissue RAS mutation sites, NeoRAS WT frequency in patients with KRAS mutation in exon 2 was significantly lower than those in exon 3 and 4 or NRAS (18.2% [18/99] vs 62.5% [5/8], P = 0.011). Regarding clinical background, there were significant differences in NeoRAS WT frequency between male vs female patients (30.6% [19/62] vs 8.9% [4/45], P = 0.008), and absence vs presence of liver metastasis (38.6% [17/44] vs 9.5% [6/63], P < 0.001). Comparing the two groups divided by the median value, NeoRAS WT was associated with smaller tumor diameter (>60.9 mm vs ≤, 3.8% [2/53] vs 38.9% [21/54], P < 0.001), lower carcinoembryonic antigen level (>38.2 ng/ml vs ≤, 11.3% [6/53] vs 31.5% [17/54], P = 0.018), and lower carbohydrate antigen 19-9 level (>158.0 U/ml vs ≤, 9.4% [5/53] vs 33.3% [18/54], P = 0.004). In the logistic regression multivariate analysis, liver metastasis absence (Odds ratio [OR], 4.62; P = 0.019), smaller tumor diameter (OR, 7.92; P = 0.012), and tissue RAS MT in other than KRAS exon 2 (OR, 9.04; P = 0.026) were significantly related to the conversion to NeoRAS WT in ctDNA.

CONCLUSIONS

Original RAS variants in tissue, tumor diameter, and liver metastasis are related to conversion to NeoRAS WT mCRC in ctDNA.

Molecular and genetic targets within metastatic colorectal cancer and associated novel treatment advancements

Colorectal cancer results in the deaths of hundreds of thousands of patients worldwide each year, with incidence expected to rise over the next two decades. In the metastatic setting, cytotoxic therapy options remain limited, which is reflected in the meager improvement of patient survival rates. Therefore, focus has turned to the identification of the mutational composition inherent to colorectal cancers and development of therapeutic targeted agents. Herein, we review the most up to date systemic treatment strategies for metastatic colorectal cancer based on the actionable molecular alterations and genetic profiles of colorectal malignancies.

Considerations for identifying the "right" subgroup in adaptive enrichment trials

Adaptive Enrichment Trials aim to make efficient use of data in a pivotal trial of a new targeted therapy to both (a) more precisely identify who benefits from that therapy and (b) improve the likelihood of successfully concluding that the drug is effective, while controlling the probability of false positives. There are a number of frameworks for conducting such a trial and decisions that must be made regarding how to identify that target subgroup. Among those decisions, one must choose how aggressively to restrict enrollment criteria based on the accumulating evidence in the trial. In this article, we empirically evaluate the impact of aggressive versus conservative enrollment restrictions on the power of the trial to detect an effect of treatment. We identify that, in some cases, a more aggressive strategy can substantially improve power. This additionally raises an important question regarding label indication: To what degree do we need a formal test of the hypothesis of no treatment effect in the exact population implied by the label indication? We discuss this question and evaluate how our answer for adaptive enrichment trials may relate to the answer implied by current practice for broad eligibility trials.

Prognosis for Metastatic Colorectal Cancer Patients Achieving Complete Response After Systemic Chemotherapy

PURPOSE

Despite marked recent advances in chemotherapy, few reports have focused on the prognosis for patients with metastatic colorectal cancer (mCRC) achieving complete response (CR) after systemic chemotherapy. This study investigated the clinical course of mCRC patients achieving CR and evaluated the role of chemotherapy in CR.

METHODS

This retrospective study searched a prospectively maintained database at the author's institute to identify medical records for mCRC patients achieving CR after systematic chemotherapy from January 2007 to March 2020.

RESULTS

The search yielded 23 patients with confirmed CR to systemic chemotherapy. Median time to CR from treatment initiation was 6.8 months. Maintenance chemotherapy was continued for 22 of 23 patients. Median duration of maintenance chemotherapy was 11.1 months. Disease progression occurred for 17 (73.9%) patients at a median 48.1-month follow-up. Median progression-free survival was 26.6 months. Median overall survival was 91.7 months.

CONCLUSIONS

Patients with CR to chemotherapy had a high probability of disease progression, but a relatively long-term prognosis. Treatment strategies after achievement of CR should be based an understanding of the high potential that tumor cells will remain. Use of maintenance chemotherapy after achievement of CR is still unclear, and the recent data do not demonstrate a negative impact for continuing maintenance chemotherapy after CR.

Potential Immunotherapy Targets for Liver-Directed Therapies, and the Current Scope of Immunotherapeutics for Liver-Related Malignancies

Liver cancer, including hepatocellular carcinoma and intrahepatic cholangiocarcinoma, is increasing in incidence and mortality across the globe. An improved understanding of the complex tumor microenvironment has opened many therapeutic doors and led to the development of novel pharmaceuticals targeting cellular signaling pathways or immune checkpoints. These interventions have significantly improved tumor control rates and patient outcomes, both in clinical trials and in real-world practice. Interventional radiologists play an important role in the multidisciplinary team given their expertise in minimally invasive locoregional therapy, as the bulk of these tumors are usually in the liver. The aim of this review is to highlight the immunological therapeutic targets for primary liver cancers, the available immune-based approaches, and the contributions that interventional radiology can provide in the care of these patients.

Agnostic Approvals in Oncology: Getting the Right Drug to the Right Patient with the Right Genomics

(1) Background: The oncology field has drastically changed with the advent of precision medicine, led by the discovery of druggable genes or immune targets assessed through next-generation sequencing. Biomarker-based treatments are increasingly emerging, and currently, six tissue-agnostic therapies are FDA-approved. (2) Methods: We performed a review of the literature and reported the trials that led to the approval of tissue-agnostic treatments and ongoing clinical trials currently investigating novel biomarker-based approaches. (3) Results: We discussed the approval of agnostic treatments: pembrolizumab and dostarlimab for MMRd/MSI-H, pembrolizumab for TMB-H, larotrectinib and entrectinib for NTRK-fusions, dabrafenib plus trametinib for BRAF V600E mutation, and selpercatinib for RET fusions. In addition, we reported novel clinical trials of biomarker-based approaches, including ALK, HER2, FGFR, and NRG1. (4) Conclusions: Precision medicine is constantly evolving, and with the improvement of diagnostic tools that allow a wider genomic definition of the tumor, tissue-agnostic targeted therapies are a promising treatment strategy tailored to the specific tumor genomic profile, leading to improved survival outcomes.