EPIC: Phase III Trial of Cetuximab Plus Irinotecan After Fluoropyrimidine and Oxaliplatin Failure in Patients With Metastatic Colorectal Cancer

Chemotherapy plus bevacizumab with or without anti-programmed death 1 immunotherapy as the second-line therapy in colorectal cancer

BACKGROUND

Patients with microsatellite stable (MSS) metastatic colorectal cancer (mCRC) typically exhibit an immunosuppressive tumor microenvironment and demonstrate a low response rate to immunotherapy. Reports suggest that chemotherapy and anti-angiogenic therapy may have the potential to enhance the response to immunotherapy in these patients. This study aims to evaluate the effectiveness and safety of chemotherapy combined with bevacizumab with or without anti-programmed death 1 (PD-1) immunotherapy as the second-line regimen for MSS mCRC.

AIM

To evaluate the effectiveness and safety of chemotherapy combined with bevacizumab with or without anti-PD-1 immunotherapy as the second-line regimen for MSS mCRC.

METHODS

A retrospective analysis was conducted on patients with MSS mCRC diagnosed at Peking University First Hospital and Jilin Cancer Hospital from January 2020 to December 2024. The patients were divided into two groups: The experimental group receiving second-line chemotherapy combined with bevacizumab and anti-PD-1 immunotherapy, and the control group receiving chemotherapy combined with bevacizumab. Propensity score matching was applied to balance potential prognostic factors, including age, gender, Eastern Cooperative Oncology Group score, number of metastases, and primary tumor site. The progression-free survival, overall survival, disease control rate, objective response rate, and treatment-related adverse reactions were compared between the two groups. Kaplan-Meier analysis and log-rank test were used to compare survival outcomes. Inverse probability of treatment weighting was used for sensitivity analysis.

RESULTS

Propensity score matching resulted in 103 matched eligible patients. The median follow-up period was 13.9 months in the matched cohort. The objective response rate was 11.5% and 9% for the experimental and control groups, respectively (P = 0.710), while the disease control rate was 76.9% and 53.2%, respectively (P = 0.058). The median progression-free survival in the experimental group was 8.27 months [95% confidence interval (CI): 6.7-14.7 months], significantly higher than that in the control group, which was 4.63 months (95%CI: 3.9-5.67 months) (hazard ratio = 0.4143, 95%CI: 0.2462-0.6972, P = 0.00066). There was a trend towards the higher median overall survival in the experimental group compared to the control group (hazard ratio = 0.4504, 95%CI: 0.1897-1.07, P = 0.064). The incidences of adverse events were similar between the two groups.

CONCLUSION

Compared with the standard second-line chemotherapy combined with bevacizumab regimen, second-line therapy that combines chemotherapy with bevacizumab and anti-PD-1 immunotherapy has demonstrated promising efficacy in the treatment of MSS mCRC, while exhibiting a similar safety profile.

Using Genomic Heterogeneity to Inform Therapeutic Decisions for Metastatic Colorectal Cancer: An Application of the Value of Heterogeneity Framework

BACKGROUND AND OBJECTIVE

Mutations in KRAS and NRAS are predictive of poor response to cetuximab and panitumumab, two anti-epidermal growth factor receptor (EGFR) monoclonal antibodies used in metastatic colorectal cancer (mCRC). Our objective was to explore the value of using KRAS and NRAS mutation status to inform third-line anti-EGFR therapy for mCRC using the value of heterogeneity (VOH) framework.

METHODS

We used administrative data to identify mCRC patients who were potentially eligible for third-line therapy in 2006-2019 in British Columbia (BC), Canada. We compared three alternative stratification policies in place during the study period: the unstratified policy where anti-EGFR therapy was not offered (2006-2009), stratification by KRAS mutation (2009-2016), and stratification by KRAS+NRAS mutation (2016-2019). We used inverse-probability-of-treatment weighting to balance covariates across the three groups. Cost and survival time were calculated using a 3-year time horizon and adjusted for censoring, with bootstrapping to characterize uncertainty. Mean net monetary benefit (NMB) was calculated at a range of threshold values. The VOH of using KRAS and NRAS mutation status to inform treatment selection was calculated as the change in NMB with increasing stratification, under current (static VOH) or perfect (dynamic VOH) information.

RESULTS

We included 2664 patients in the analysis. At a willingness-to-pay of CA$100,000/ life-year gained (LYG), stratification on KRAS mutation status provided a static VOH of CA$1565 per patient; further stratification on KRAS+NRAS provided additional static VOH of CA$594. The static VOH exceeded the marginal cost of genomic testing under both policies.

CONCLUSIONS

Stratification of anti-EGFR therapy by KRAS and NRAS mutation status can provide additional value at a threshold of CA$100,000/LYG. There is diminishing marginal value and increasing marginal costs as the policy becomes more stratified. The VOH framework can illustrate the value of subgroup-specific decisions in a comprehensive way, to better inform targeted treatment policies.

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.

1-year efficacy results after MR-guided risk-adapted stereotactic radiotherapy of infra-diaphragmatic oligometastases in a multicenter phase II trial

BACKGROUND AND PURPOSE

The SOFT (Stereotactic ablative radiotherapy of infra-diaphragmatic sOFT tissue metastases) trial assesses the safety and efficacy of risk-adapted MR-guided stereotactic ablative radiotherapy (SABR) of infra-diaphragmatic soft tissue metastasis in patients with oligometastatic disease (OMD) (clinicaltrials.gov ID NCT04407897). This paper reports the one-year efficacy analysis and evaluates associations between local control (LC) and clinical and dosimetric parameters.

MATERIALS AND METHODS

This investigator-initiated, multicenter, single-arm, phase 2 study recruited patients from four MR-linac centers in Denmark and the US. Patients with De novo or recurrent OMD with ≤5 metastases in ≤3 organs and patients with induced OMD or oligoprogressive disease (OPD) with ≤3 metastases were eligible. Fractionation schemes were 45-75 Gy in 3-8 fractions.

RESULTS

The trial included 121 patients with 147 oligometastatic lesions, primarily in the liver (41 %), lymph nodes (35 %), or adrenal glands (14 %). The median follow-up time was 13.0 months, interquartile range (IQR) (11.7,13.7) months. The 1-year LC rate was 89 %, 95 % confidence interval (CI) (83,94 %). We did not observe any statistically significant associations between LC and clinical and dosimetric parameters. The median progression-free survival was 7.1 months, 95 % CI (6.0,9.4). One- and two-year overall survival was 82.6 %, 95 % CI (76.2 %,89.7 %), and 65.1 %, 95 % CI (56.4 %,75.3 %). Sixty-one patients (50 %) were kept off systemic therapy throughout the one-year follow-up.

CONCLUSION

In our study, treatment with risk-adapted, MR-guided SABR resulted in a high one-year local control and survival rate and could keep half of the patients off systemic therapy within the first year of follow-up.

Real-world treatment outcomes from nationwide Onco-colon Turkey registry in RAS wild-type patients treated with biologics second-line mCRC

Backgrounds and ObjectivesColorectal cancer is one of the leading causes of mortality both globally and in our country. In Turkey, we conducted a multicenter investigation into the effectiveness of second-line treatments and real-life data for patients with RAS wild-type metastatic colorectal cancer (NCT04757311).Materials and MethodsIn this retrospective analysis, records from 28 centers were collected, and histopathological, molecular, and clinical characteristics were documented. Patients were categorized into groups based on their second-line biological treatments: anti-EGFR (Group A and Group B, panitumumab and cetuximab) and anti-VEGF (Group C, bevacizumab and aflibercept). They were then compared within these groups.ResultsA total of 588 patients with documented RAS wild-type status were evaluated. The median OS was 15.7, 14.3 and 14.7 months in Group A, Group B and Group C, respectively (p  =  0.764). The median PFS of the patients in second-line setting that received panitumumab, cetuximab and bevacizumab/aflibercept were 7.8, 6.6 and 7.4 months, respectively (p  =  0.848).ConclusionAccording to the results of our real-life data study, there is no significant difference in efficiency between the combination of biological agent and chemotherapy used in the second-line treatments.

Blocking Tumoral Angiogenesis VEGF/VEGFR Pathway: Bevacizumab-20 Years of Therapeutic Success and Controversy

The "angiogenesis switch"-defined as the active process by which solid tumors develop their own circulation-plays an important role in both tumoral growth and propagation. As the malignant tumor grows and reaches a critical size, the metabolic needs as a function of an ever-increasing distance to the nearest emergent blood vessel, can no longer be covered by the microenvironment of the peritumoral tissue. Although a relatively discrete process, the "angiogenic switch" acts as a limiting stage of tumoral development present from the avascular hyperplasia phase to the vascularized neoplastic phase, providing support for tumor expansion and metastasis. Over time, research has focused on blocking the angiogenetic pathways (such as VEGF/VEGFR signaling axis) leading to the development of targeted therapeutic agents such as Bevacizumab. Objectives: We conducted a review of the molecular principles of tumoral angiogenesis and we tried to follow the history of Bevacizumab from its first approval for human usage 20 years ago to current days, focusing on the impact this agent had in solid tumor therapy. A comprehensive review of clinical trials pertaining to Bevacizumab (from the era of the preclinic trials leading to approval for human usage, to the more recent randomized trial focusing on combination targeted therapy) further details the role of this drug. We aimed to establish if this ancient drug continues to have a place in modern oncology. Conclusions: Bevacizumab, one of the first drugs targeting tumoral microenvironment, remains one of the most important oncologic agents blocking the VEGF/VEGFR angiogenic pathway. otherwise, history of 20 years marked by numerous controversies (ranging from methodological errors of clinical trials to withdrawal of approval for human usage in breast cancer patients, from discussions about severe side effects to resistance to therapy and limited efficacity), Bevacizumab continues to provide an optimal therapeutic option for many solid tumors that previously had little to no means of treatment, improving otherwise bleak outcomes. Even in the era of personalized precision oncology, Bevacizumab continues to be a key element in many therapeutic regimens both as monotherapy and in combination with newer targeted agents.

A phase two trial evaluating FOLFIRI plus aflibercept after failure of FOLFOXIRI plus bevacizumab in patients with unresectable metastatic colorectal cancer

BACKGROUND

FOLFOXIRI plus bevacizumab (BEV) is an option for first-line treatment of metastatic colorectal cancer (mCRC). However, there is no consensus on the optimal treatment strategy when disease progresses. The EFFORT open-label, multicenter, single-arm phase II study investigated whether FOLFIRI plus aflibercept retains activity after progression of FOLFOXIRI plus BEV treatment.

METHODS

The patients with unresectable mCRC who failed first-line FOLFOXIRI plus BEV received FOLFIRI plus aflibercept. The primary endpoint was progression-free survival (PFS) in the full analysis set (FAS). Angiogenic biomarkers were measured before treatment initiation.

RESULTS

From April 2019 to May 2021, 35 patients were enrolled and 34 were analysed in the FAS population (men, 18; median age, 63 years [range: 32-78]). The primary tumor was left-sided in most cases (23/34), 23 patients were RAS mutant, 3 patients had BRAF V600E mutation and 27 patients had liver metastases. The primary end-point was met with a median PFS of 4.3 months [80% confidence interval [CI] 3.7-5.1]. Median overall survival was 15.2 months [95% CI 8.9-22.7]. Per RECIST, there were 1 complete response, 4 partial responses, 21 stable diseases and 8 disease progressions. Overall response rate was 14.7% [95% CI 5.0-31.1], and disease control rate was 76.5% [95% CI 58.8-89.3]. Responses were more common in patients with high VEGF-C, low VEGF-D and low PlGF levels before treatment.

CONCLUSION

FOLFIRI plus aflibercept, administered after failure of FOLFOXIRI plus BEV, is effective and has a manageable safety profile. This regimen may be a useful second-line treatment option for these patients.

The efficacy of targeted therapy and/or immunotherapy with or without chemotherapy in patients with colorectal cancer: A network meta-analysis

BACKGROUND

The use of targeted drugs and immunotherapy has significantly impacted the treatment of Colorectal Cancer. However, horizontal comparison among various regimens is extremely rare. Therefore, we evaluated the survival efficacy of multiple treatment regimens of targeted therapy and/or immunotherapy with or without chemotherapy in patients with Colorectal Cancer.

METHODS

A systematic search was conducted in PubMed, EMBASE, and Cochrane databases, covering the period from the establishment of the databases to October 29, 2024. To obtain articles that met the inclusion and exclusion criteria and contained the required data for conducting a network meta-analysis (NMA). The NMA evaluated overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 90 studies were identified, comprising a sample size of 33,167 subjects. In terms of PFS, compared with simple chemotherapy strategies, most of the other single or combined strategies are significantly effective, among which targeted therapy strategies have more advantages. Encorafenib + Binimetinib + Cetuximab (ENC-BIN-CET) shows significant benefits in all comparisons except when compared with Chemotherapy + Cetuximab + Dalotuzumab (Chemo-CET-DAL), Encorafenib + Cetuximab (ENC-CET), and Panitumumab + Sotorasib (PAN-SOT). The ENC-CET and PAN-SOT targeted strategies also show significant benefits. Pembrolizumab (PEM) monotherapy has advantages over all others except when it is not superior to some targeted strategies. Chemotherapy + Bevacizumab + Atezolizumab is only inferior to some strategies. In terms of OS, the combinations of Chemotherapy + Bevacizumab, ENC-CET, Chemotherapy + Panitumumab, and ENC-BIN-CET are superior to simple chemotherapy regimens. ENC-BIN-CET shows OS benefits in all comparisons except some. ENC-CET significantly improves OS in most cases, and PEM also significantly improves OS in some regimens. In the probability ranking of OS and PFS, ENC-BIN-CET has the best effect, followed by ENC-CET.

CONCLUSIONS

In conclusion, pembrolizumab is still effective in prolonging survival. Dual- and triple-drug targeted strategies are the best in terms of OS and PFS, and the combination of targeted immunotherapy and chemotherapy also works. However, not all combinations are beneficial. As targeted drugs play an active role, specific drugs for colorectal cancer regimens should be carefully selected.

Rechallenge therapy versus tyrosine kinase inhibitor (TKI) for advanced metastatic colorectal cancer: a retrospective study

Currently, the standard third-line treatment options for advanced metastatic colorectal cancer (mCRC) include regorafenib, fruquintinib, and trifluridine/tipiracil (TAS-102), but these drugs have limited clinical efficacy. This study aims to evaluate the efficacy and survival outcomes of tyrosine kinase inhibitor (TKI) versus chemotherapy rechallenge in third-line treatment for advanced mCRC patients. From January 2019 to December 2022, 107 patients met the inclusion criteria. After 1:1 matching, there were 34 patients in both the TKI and rechallenge groups. Cox regression analysis was performed to identify independent predictive factors. The result indicated that Eastern Cooperative Oncology Group (ECOG) score of 0-1 (hazard ratio [HR] = 0.03, 95% confidence interval [CI]: 0.01-0.17; P < 0.001) and chemotherapy rechallenge (HR = 0.43, 95% CI: 0.23-0.79; P = 0.007) were independent protective factors for overall survival (OS). Patient-Generated Subjective Global Assessment (PG-SGA) score of 0-3 (HR = 0.43, 95% CI: 0.23-0.80; P = 0.008), progression-free survival (PFS) of frontline treatment (HR = 0.66, 95% CI: 0.43-1.00, P = 0.047) and chemotherapy rechallenge (HR = 0.42, 95% CI: 0.24-0.73; P = 0.002) were independent protective factors for PFS. Kaplan-Meier survival analysis showed that the median OS in the rechallenge group was 13.2 months (95% CI: 9.6-19.3), compared with 7.7 months (95% CI: 6.5-14.5) in the TKI group, with a statistically significant difference (HR = 0.47, 95% CI: 0.26-0.86; P = 0.013). The median PFS for the rechallenge group was 5.0 months (95% CI: 4.3-6.7), compared with 3.4 months (95% CI: 2.7-4.8) in the TKI group, with a statistically significant difference too (HR = 0.54, 95% CI: 0.32-0.91; P = 0.019). Furthermore, subgroup analysis showed that in Group A, the rechallenge group also had superior median OS and PFS compared with the TKI group. In conclusion, while TKIs are the current standard for third-line treatment in mCRC patients, chemotherapy rechallenge is a more effective option for patients who have achieved disease control in the first two lines of treatment.

Second-line systemic treatment for metastatic colorectal cancer: A systematic review and Bayesian network meta-analysis based on RCT

BACKGROUND

The optimal second-line systemic treatment for metastatic colorectal cancer (mCRC) is inconclusive.

METHODS

We searched PubMed, Web of Science, EMBASE, and Cochrane Library for RCTs comparing second-line systemic treatments for mCRC from the inception of each database up to February 3, 2024. Markov Chain Monte Carlo (MCMC) technique was used in this network meta-analysis (NMA) to generate the direct and indirect comparison results among multiple treatments in progression-free survival (PFS), overall response rate (ORR), overall survival (OS), complete response (CR), partial response (PR), grade 3 and above adverse events (Grade ≥ 3AE), and any adverse events (Any AE). The surface under the cumulative ranking curve (SUCRA) was adopted to evaluate the probability of each treatment being the optimum intervention. Subgroup analyses were performed based on the RAS gene status.

RESULTS

A total of 47 randomized controlled trials were included, involving 16,925 patients and 44 second-line systemic treatments. In improving OS, FOLFOX + Bevacizumab + Erlotinib exhibited significant superiority (SUCRA:92.7%). In improving PFS, Irinotecan + CMAB009 (SUCRA:86.4%) had advantages over other treatments. FOLFIRI + Trebananib (SUCRA:88.1%) had a significant advantage in improving ORR. Among multiple second-line treatments, the SUCRA values of FOLFOX + Bevacizumab in PFS, OS, ORR, and PR were 83.4%, 74.0%, 81.1%, and 86.1%, respectively, and the safety was not significantly different from other interventions. Subgroup analyses showed that FOLFIRI + Bevacizumab + panitumumab ranked among the top in survival outcomes in the RAS-mutant population (OS SUCRA: 87.9%; PFS SUCRA: 70.2%); whereas in the RAS-wild-type population, FOLFIRI + Bevacizumab significantly improved survival outcomes (OS SUCRA: 73.2%; PFS SUCRA: 65.1%).

CONCLUSION

For most people, FOLFOX + Bevacizumab may be the best second-line systemic treatment regimen for mCRC. For RAS-mutant populations, FOLFIRI + Bevacizumab + Panitumumab is recommended. However, the therapeutic effect may be affected by the patient's physiological state, and clinicians should apply it based on actual conditions.

Precision Medicine for Metastatic Colorectal Cancer: Where Do We Stand?

Metastatic colorectal cancer is a leading cause of cancer-related death across the world. The treatment paradigm has shifted away from systemic chemotherapy alone to include targeted therapy and immunotherapy. The past two decades have been characterized by increased investigation into molecular profiling of colorectal cancer. These molecular profiles help physicians to better understand colorectal cancer biology among patients with metastatic disease. Additionally, improved data on genetic pathways allow for specific therapies to be targeted at the underlying molecular profile. Investigation of the EGFR, VEGF, HER2, and other pathways, as well as deficient mismatch repair, has led to the development of multiple targeted therapies that are now utilized in the National Comprehensive Cancer Network guidelines for colon and rectal cancer. While these new therapies have contributed to improved survival for metastatic colorectal cancer, long-term survival remains poor. Additional investigation to understand resistance to targeted therapy and development of new targeted therapy is necessary. New therapies are under development and are being tested in the preclinical and clinical settings. The aim of this review is to provide a comprehensive evaluation of molecular profiling, currently available therapies, and ongoing obstacles in the field of colorectal cancer.

Real-world cost-effectiveness of panel-based genomic testing to inform therapeutic decisions for metastatic colorectal cancer

BACKGROUND

Mutations in KRAS and NRAS are associated with a lack of response to cetuximab and panitumumab, two biologics used for third-line therapy of metastatic colorectal cancer (mCRC). In British Columbia, Canada, eligibility for cetuximab or panitumumab was first based on single-gene KRAS testing. OncoPanel, a multi-gene next-generation sequencing panel with both KRAS and NRAS, was introduced in 2016. Our objective was to estimate the real-world cost-effectiveness of OncoPanel versus to single-gene KRAS testing to inform eligibility for cetuximab or panitumumab in mCRC.

METHODS

Using population-based administrative health data, we identified a cohort of mCRC patients who had received a KRAS or OncoPanel test, and completed prior chemotherapy in 2010-2019. We matched KRAS- and OncoPanel-tested patients (1:1) using genetic matching to balance baseline covariates. Mean and incremental 3-year costs, survival, and quality-adjusted survival were estimated using inverse-probability-of-censoring weighting and bootstrapping. We conducted scenario-based sensitivity analysis for key costs and assumptions.

FINDINGS

All OncoPanel-tested cases (n=371) were matched to a KRAS-tested comparator. In the KRAS and OncoPanel groups, respectively, 55·8 % and 41·2 % of patients were potentially eligible for cetuximab or panitumumab based on mutation status. Incremental cost and effectiveness of OncoPanel were $72 (95 % CI: -6387, 6107), -0·004 life-years (95 % CI: -0·119, 0·113), and -0·011 quality-adjusted life-years (95 % CI: -0·094, 0·075). Reductions in systemic therapy costs were offset by increased costs in other resources. Results were moderately sensitive to time horizon and changes in testing or treatment cost.

INTERPRETATION

The use of OncoPanel resulted in more precise targeting of cetuximab and panitumumab, but there was no change in incremental cost or quality-adjusted survival. Understanding the balance of costs achieved in practice can provide insight into the effect of future changes in testing policy, test cost, treatment eligibility, or drug prices in this setting.

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.

Bayesian meta-analysis for evaluating treatment effectiveness in biomarker subgroups using trials of mixed patient populations

During drug development, evidence can emerge to suggest a treatment is more effective in a specific patient subgroup. Whilst early trials may be conducted in biomarker-mixed populations, later trials are more likely to enroll biomarker-positive patients alone, thus leading to trials of the same treatment investigated in different populations. When conducting a meta-analysis, a conservative approach would be to combine only trials conducted in the biomarker-positive subgroup. However, this discards potentially useful information on treatment effects in the biomarker-positive subgroup concealed within observed treatment effects in biomarker-mixed populations. We extend standard random-effects meta-analysis to combine treatment effects obtained from trials with different populations to estimate pooled treatment effects in a biomarker subgroup of interest. The model assumes a systematic difference in treatment effects between biomarker-positive and biomarker-negative subgroups, which is estimated from trials which report either or both treatment effects. The systematic difference and proportion of biomarker-negative patients in biomarker-mixed studies are used to interpolate treatment effects in the biomarker-positive subgroup from observed treatment effects in the biomarker-mixed population. The developed methods are applied to an illustrative example in metastatic colorectal cancer and evaluated in a simulation study. In the example, the developed method improved precision of the pooled treatment effect estimate compared with standard random-effects meta-analysis of trials investigating only biomarker-positive patients. The simulation study confirmed that when the systematic difference in treatment effects between biomarker subgroups is not very large, the developed method can improve precision of estimation of pooled treatment effects while maintaining low bias.

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.

Second-line treatment strategies for RAS wild-type colorectal cancer: A systematic review and Network Meta-analysis (NMA)

BACKGROUND

The optimal strategy for second-line (IIL) treatment in KRAS wt metastatic colorectal cancer (mCRC) is not determined yet.

METHODS

A random-effect NMA of phase II/III RCTs was conducted to evaluate IIL treatment for all-RAS wt mCRC, comparing anti-EGFR or anti-VEGF, and chemotherapy (CT).

RESULTS

Overall, 11 RCTs (3613 patients) were included. In KRAS wt patients, PFS was improved with anti-VEGF (HR 0.43) and anti-EGFR (HR 0.63) vs CT. However, anti-VEGF based therapy had the highest likelihood of being ranked as the best treatment in terms of PFS (SUCRA 99.3%) and OS (SUCRA 99.4%). Bevacizumab-based treatment is most likely to be the best treatment in terms of PFS (SUCRA 89.1%) and OS (SUCRA 86.7%).

CONCLUSIONS

Second line treatment with anti-VEGF and anti-EGFR improved PFS in mCRC patients, however, anti-VEGF based therapy, particularly CT plus bevacizumab, is the best treatment according to SUCRA in terms of PFS and OS.

Cetuximab every 2 weeks versus standard weekly dosing administration schedule

Cetuximab every 2 weeks (Q2W) dosing schedule is approved by the US FDA and by the Japanese Pharmaceuticals and Medical Devices Agency in patients with metastatic colorectal cancer and squamous cell carcinoma of the head and neck. Phase II trials have found comparable efficacy and safety for the weekly (Q1W) and Q2W schedules, and real-world studies have shown noninferiority of the Q2W compared with the Q1W schedule. Several guidelines recommend cetuximab Q2W administration as an alternative to the Q1W dosing schedule. Cetuximab Q2W can be administered with a Q2W dose of chemotherapy, making it a more convenient option to the Q1W schedule, potentially resulting in reduced costs for administration, increased flexibility for clinical staff and improved patient adherence.

Anti-angiogenesis in colorectal cancer therapy

The morbidity of colorectal cancer (CRC) has risen to third place among malignant tumors worldwide. In addition, CRC is a common cancer in China whose incidence increases annually. Angiogenesis plays an important role in the development of tumors because it can bring the nutrients that cancer cells need and take away metabolic waste. Various mechanisms are involved in the formation of neovascularization, and vascular endothelial growth factor is a key mediator. Meanwhile, angiogenesis inhibitors and drug resistance (DR) are challenges to consider when formulating treatment strategies for patients with different conditions. Thus, this review will discuss the molecules, signaling pathways, microenvironment, treatment, and DR of angiogenesis in CRC.

Impacts of systemic treatments on health-related quality of life for patients with metastatic colorectal cancer: a systematic review and network meta-analysis

OBJECTIVE

There is limited evidence of comparative results among different treatments regarding impacts of Health-Related Quality of Life (HRQoL) for patients with metastatic colorectal cancer (mCRC). We aimed to compare efficacy of systemic treatments on HRQoL among patients with mCRC.

METHODS

We collected randomized controlled trials (RCTs) reported in English up until July 2023, from databases including PubMed, Embase, Cochrane Library, ClinicalTrials.gov, and prominent conference databases, for this Bayesian network meta-analysis. Phase 2 or 3 trials that evaluated at least two therapeutic regimens were included. Primary outcomes were short-term and long-term mean changes in EORTC QLQ-C30 global health status/quality of life (GHS/QoL) scores. Secondary outcome was mean change in EQ-5D health utility scores. Mean differences (MDs) with 95% confidence intervals (CIs) were used as effect size. Subgroup analysis was performed based on whether patients received systemic treatments before. We conducted various sensitivity analyses, including differentiating between chemotherapy types, and analyzed patient cohorts with non-specified gene expression levels as well as those with target KRAS expression statuses. The current systematic review protocol was registered on PROSPERO (CRD42023453315 and CRD42023420498).

RESULTS

Immunotherapy and targeted therapy significantly improved HRQoL over chemotherapy, with MDs of 9.27 (95% CI: 3.96 to 14.6) and 4.04 (95% CI: 0.11 to 7.94), respectively. Monotherapy significantly outperformed both combination therapy (MD 5.71, 95%CI 0.78 to 10.63) and no active treatment (MD 3.7, 95%CI 1.41 to 6.01) regarding GHS/QoL in the short-term. Combining targeted therapy with chemotherapy did not improve HRQoL. Focusing on HRQoL, cetuximab excelled when gene expression baselines were unspecified. Subgroup and sensitivity analyses upheld these robust findings, unaffected by model or patient baseline characteristics. Evidence from clinical trials without specific gene level data suggested that monotherapies, especially targeted therapies such as cetuximab, demonstrated superiority in HRQoL. For KRAS wild-type patients, no significant HRQoL differences emerged between chemotherapy, targeted therapy, or their combination..

CONCLUSIONS

Targeted therapies and immunotherapy demonstrate superior HRQoL benefits, monotherapy such as cetuximab is associated with significant improvements as compared to combination therapy. However, tailoring these results to individual gene expression profiles requires more evidence.

The effective combination therapies with irinotecan for colorectal cancer

Colorectal cancer is the third most common type of cancer worldwide and has become one of the major human disease burdens. In clinical practice, the treatment of colorectal cancer has been closely related to the use of irinotecan. Irinotecan combines with many other anticancer drugs and has a broader range of drug combinations. Combination therapy is one of the most important means of improving anti-tumor efficacy and overcoming drug resistance. Reasonable combination therapy can lead to better patient treatment options, and inappropriate combination therapy will increase patient risk. For the colorectal therapeutic field, the significance of combination therapy is to improve the efficacy, reduce the adverse effects, and improve the ease of treatment. Therefore, we explored the clinical advantages of its combination therapy based on mechanism or metabolism and reviewed the rationale basis and its limitations in conducting exploratory clinical trials on irinotecan combination therapy, including the results of clinical trials on the combination potentiation of cytotoxic drugs, targeted agents, and herbal medicine. We hope that these can evoke more efforts to conduct irinotecan in the laboratory for further studies and evaluations, as well as the possibility of more in-depth development in future clinical trials.

Cetuximab as a Key Partner in Personalized Targeted Therapy for Metastatic Colorectal Cancer

Cetuximab, a chimeric IgG1 monoclonal antibody targeting the epidermal growth factor receptor (EGFR), has revolutionized personalized treatment of metastatic colorectal cancer (mCRC) patients. This review highlights the mechanism of action, characteristics, and optimal indications for cetuximab in mCRC. Cetuximab has emerged as a pivotal partner for novel therapies in specific molecular subgroups, including BRAF V600E, KRAS G12C, and HER2-altered mCRC. Combining cetuximab with immunotherapy and other targeted agents further expands the therapeutic landscape, offering renewed hope for mCRC patients who face the development of resistance to conventional therapies. Ongoing clinical trials have continued to uncover innovative cetuximab-based treatment strategies, promising a brighter future for mCRC patients. This review provides a comprehensive overview of cetuximab's role and its evolving importance in personalized targeted therapy of mCRC patients, offering valuable insights into the evolving landscape of colorectal cancer treatment.

Raltitrexed Chemotherapy Regimen Plus Bevacizumab as Second-Line Treatment for Metastatic Colorectal Cancer: A Prospective Multicenter Phase II Trial

OBJECTIVES

Clinical studies have shown that bevacizumab plus chemotherapy significantly improves efficacy in metastatic colorectal cancer (mCRC). This prospective study aims to investigate the efficacy and safety of changing second-line treatment to raltitrexed-based chemotherapy regimens plus bevacizumab in mCRC patients who have failed the first-line fluorouracil-based chemotherapy regimen with or without bevacizumab/cetuximab.

METHODS

This is a prospective, open-label, multicenter, phase II clinical study. A total of 100 patients with mCRC after failure of the first-line fluorouracil-based chemotherapy regimen with or without bevacizumab/cetuximab were enrolled from November 2016 to October 2021, and received second-line raltitrexed-based chemotherapy regimen plus bevacizumab. Patients were treated for 6 cycles, and efficacy evaluation over stable disease were followed by maintenance treatment of bevacizumab and raltitrexed until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR), safety, and toxicity.

RESULTS

Ninety-four patients were treated with SALIRI (raltitrexed + irinotecan) plus bevacizumab, and six patients with SALOX (raltitrexed + oxaliplatin) plus bevacizumab. Median PFS was 8.4 (95% CI: 6.2-11.0) months, including 8.2 (95% CI 6.2, 11.0) months in the SALIRI group and 11.6 (95% CI 3.1, NA) months in the SALOX group. Median OS was 17.6 (95% CI 15.2, 22.0) months in the SALIRI group and 17.1 (95% CI 4.1, NA) months in the SALOX group. ORR and DCR were 25.5% and 87.2% in the SALIRI group, and 33.3% and 83.3% in the SALOX group, respectively. A low incidence of grade 3-4 adverse events was observed.

CONCLUSIONS

Raltitrexed-based chemotherapy regimens plus bevacizumab improved survival duration in mCRC patients with failed first-line therapy. Therefore, treatment with raltitrexed-based chemotherapy regimens plus bevacizumab could be a superior therapeutic option for second-line chemotherapy in mCRC (ClinicalTrials.gov registration number: NCT03126071).

Targeted Inhibitors of EGFR: Structure, Biology, Biomarkers, and Clinical Applications

Members of the EGFR family of tyrosine kinase receptors are major regulators of cellular proliferation, differentiation, and survival. In humans, abnormal activation of EGFR is associated with the development and progression of many cancer types, which makes it an attractive target for molecular-guided therapy. Two classes of EGFR-targeted cancer therapeutics include monoclonal antibodies (mAbs), which bind to the extracellular domain of EGFR, and tyrosine kinase inhibitors (TKIs), which mostly target the intracellular part of EGFR and inhibit its activity in molecular signaling. While EGFR-specific mAbs and three generations of TKIs have demonstrated clinical efficacy in various settings, molecular evolution of tumors leads to apparent and sometimes inevitable resistance to current therapeutics, which highlights the need for deeper research in this field. Here, we tried to provide a comprehensive and systematic overview of the rationale, molecular mechanisms, and clinical significance of the current EGFR-targeting drugs, highlighting potential candidate molecules in development. We summarized the underlying mechanisms of resistance and available personalized predictive approaches that may lead to improved efficacy of EGFR-targeted therapies. We also discuss recent developments and the use of specific therapeutic strategies, such as multi-targeting agents and combination therapies, for overcoming cancer resistance to EGFR-specific drugs.

Evaluation of the additional prophylactic effect of topical steroid ointment to systemic minocycline against anti-epidermal growth factor antibody-induced skin toxicities in metastatic colorectal cancer treatment

BACKGROUND

Anti-epidermal growth factor receptor (EGFR) antibodies often cause skin toxicities. Preemptive skin treatments using systemic antibiotics with or without topical steroid are reportedly effective although the most suitable method remains unclear. This study aimed to determine whether combination prophylaxis using systemic minocycline and topical steroid is superior to minocycline alone in a real-world metastatic colorectal cancer (mCRC) treatment.

METHODS

Patients with mCRC (n = 87) who received anti-EGFR monoclonal antibodies were retrospectively assessed. The primary objective was to compare the incidence of grade ≥ 2 overall skin toxicities during all treatment periods between the control group receiving prophylactic minocycline 100 mg/day, and the combination prophylaxis group receiving minocycline 100 mg/day + topical steroid. The incidence of each skin symptom was also evaluated.

RESULTS

The incidence of grade ≥ 2 overall skin toxicities was 63.6% in the control and 56.9% in the combination groups, with no significant difference (P = 0.63). Similarly, the incidence of grade ≥ 2 dry skin, fissures, paronychia, and pruritus did not significantly differ. In addition, incidence of all-grade skin toxicities was not different. However, the incidence of grade ≥ 2 papulopustular rashes was significantly lower in the combination group (23.1% vs. 50.0%, P = 0.03). Propensity score-matched analysis supported these results. Multivariate logistic regression analysis showed no significant association between combination prophylaxis and grade ≥ 2 overall skin toxicities, but it did show a reduction in grade ≥ 2 papulopustular rashes.

CONCLUSION

Adding topical steroids to systemic minocycline did not mitigate grade ≥ 2 overall skin toxicities induced by anti-EGFR antibodies; however, it significantly improved papulopustular rashes.

A review of targeted therapy and immune checkpoint inhibitors for metastatic colorectal cancer

Surgical resection is the cornerstone of treatment for metastatic colorectal cancer (CRC) and offers the best chance at long-term survival. Unfortunately, most patients do not present with resectable metastatic disease and, among patients who do undergo curative-intent resection, many will develop recurrence. In turn, patients require a multi-disciplinary treatment approach with a combination of chemotherapy, surgery, radiation, and/or liver directed therapies that is guided by patient disease burden and clinical status. The development of targeted therapies has led to varying success in other cancers and has emerged as a treatment option for patients with metastatic CRC. While cytotoxic chemotherapy aims to kill cells as they replicate, targeted therapies are directed at biologic features of cancers, like angiogenesis or immune checkpoints. Targeted therapy can facilitate a more treatment tailored approach to the unique genomic alterations of the tumor and hopefully deliver more personalized therapy. We herein provide a systematic review of approved targeted therapies and immune checkpoint inhibitors for metastatic CRC and provide an overview of the current literature.

Irinotecan-Induced Toxicity: A Pharmacogenetic Study Beyond UGT1A1

BACKGROUND AND OBJECTIVE

Side effects of irinotecan treatment can be dose limiting and may impair quality of life. In this study, we investigated the correlation between single nucleotide polymorphisms (SNPs) in genes encoding enzymes involved in the irinotecan metabolism and transport, outside UGT1A1, and irinotecan-related toxicity. We focused on carboxylesterases, which are involved in formation of the active metabolite SN-38 and on drug transporters.

METHODS

Patients who provided written informed consent at the Erasmus Medical Center Cancer Institute to the Code Geno study (local protocol: MEC02-1002) or the IRI28-study (NTR-6612) were enrolled in the study and were genotyped for 15 SNPs in the genes CES1, CES2, SLCO1B1, ABCB1, ABCC2, and ABCG2.

RESULTS

From 299 evaluable patients, 86 patients (28.8%) developed severe irinotecan-related toxicity. A significantly higher risk of toxicity was seen in ABCG2 c.421C>A variant allele carriers (P = 0.030, OR 1.88, 95% CI 1.06-3.34). Higher age was associated with all grade diarrhea (P = 0.041, OR 1.03, 95% CI 1.00-1.06). In addition, CES1 c.1165-41C>T and CES1 n.95346T>C variant allele carriers had a lower risk of all-grade thrombocytopenia (P = 0.024, OR 0.42, 95% CI 0.20-0.90 and P = 0.018, OR 0.23, 95% CI 0.08-0.79, respectively).

CONCLUSION

Our study indicates that ABCG2 and CES1 SNPs might be used as predictive markers for irinotecan-induced toxicity.

Real-World Cost Effectiveness of a Policy of KRAS Testing to Inform Cetuximab or Panitumumab for Third-Line Therapy of Metastatic Colorectal Cancer in British Columbia, Canada

BACKGROUND

Cetuximab and panitumumab, two anti-EGFR therapies, are widely used for third-line therapy of metastatic colorectal cancer (mCRC) with wild-type KRAS, but there remains uncertainty around their cost effectiveness. The objective of this analysis was to conduct a real-world cost-effectiveness analysis of the policy change introducing KRAS testing and third-line anti-EGFR therapy mCRC in British Columbia (BC), Canada.

METHODS

We conducted secondary analysis of administrative data for a cohort of mCRC patients treated in BC in 2006-2015. Patients potentially eligible for KRAS testing and third-line therapy after the policy change (July 2009) were matched 2:1 to pre-policy patients using genetic matching on propensity score and baseline covariates. Costs and survival time were calculated over an 8-year time horizon, with bootstrapping to characterize uncertainty around endpoints. Cost effectiveness was expressed using incremental cost-effectiveness ratios (ICER) and the probability of cost effectiveness at a range of thresholds.

RESULTS

The cohort included 1757 mCRC patients (n = 456 pre-policy and n = 1304 post-policy; of those, n = 420 received cetuximab or panitumumab). There was a significant increase in survival and cost following the policy change. Adoption of KRAS testing and anti-EGFR therapy had an ICER of CA$73,759 per life-year gained (LYG) (95% CI 46,133-186,446). In scenario analysis, a reduction in cetuximab and panitumumab cost of at least 50% was required to make the policy change cost effective at a threshold of CA$50,000/LYG.

CONCLUSION

A policy of third-line anti-EGFR therapy informed by KRAS testing may be considered cost effective at thresholds above CA$70,000/LYG. Reduction in drug costs, through price discounts or potential future biosimilars, would make anti-EGFR therapy considerably more cost effective. By using real-world data for a large cohort with long follow-up we can assess the value of a policy of KRAS testing and anti-EGFR therapy achieved in practice.

Current Status of Angiogenesis Inhibitors as Second-Line Treatment for Unresectable Colorectal Cancer

Colorectal cancer is the third most common disease and the second most common cause of death around the world. The drug for second-line treatment depends on the drugs used in first-line treatment and the biomarker status. As biomarkers, the RAS gene, BRAF gene, and dMMR/MSI-H, TMB-H, and HER2 statuses have been established in clinical practice, and the corresponding molecularly targeted therapeutic agents are selected based on the biomarker status. Given the frequency of biomarkers, it is assumed that when patients move on to second-line treatment, an angiogenesis inhibitor is selected in many cases. For second-line treatment, three angiogenesis inhibitors, bevacizumab (BEV), ramucirumab (RAM), and aflibercept (AFL), are available, and one of them is combined with cytotoxic agents. These three angiogenesis inhibitors are known to inhibit angiogenesis through different mechanisms of action. Although no useful biomarkers have been established for the selection of angiogenesis inhibitors, previous biomarker studies have suggested that angiogenesis-related factors such as VEGF-A and VEGF-D might be predictors of the therapeutic efficacy of angiogenesis inhibitors. These biomarkers are measured as protein levels in plasma and are considered to be promising biomarkers. We consider that the rationale for selecting among these three angiogenesis inhibitors should be clarified to benefit patients.

SEOM-GEMCAD-TTD clinical guidelines for the systemic treatment of metastatic colorectal cancer (2022)

Colorectal cancer (CRC) is the second leading cause of cancer deaths in Spain. Metastatic disease is present in 15-30% of patients at diagnosis and up to 20-50% of those with initially localized disease eventually develop metastases. Recent scientific knowledge acknowledges that this is a clinically and biologically heterogeneous disease. As treatment options increase, prognosis for individuals with metastatic disease has steadily improved over recent decades. Disease management should be discussed among experienced, multidisciplinary teams to select the most appropriate systemic treatment (chemotherapy and targeted agents) and to integrate surgical or ablative procedures, when indicated. Clinical presentation, tumor sidedness, molecular profile, disease extension, comorbidities, and patient preferences are key factors when designing a customized treatment plan. These guidelines seek to provide succinct recommendations for managing metastatic CRC.

Computational prediction and analysis of targeting 17-beta-hydroxysteroid dehydrogenase (17-beta-HSD1) with natural products for colorectal cancer treatment

Colorectal cancer (CRC) is a type of cancer that occurs in the colon or rectum and kills millions of people each year. Steroid hormones are interconverted between their potent, high-affinity forms by using 17-beta hydroxysteroid dehydrogenase for their respective receptors in these tissues, with a high probability of random genetic errors. Currently, 17-beta-HSD1 studies have revealed the role of steroid metabolism in the development and proliferation of colorectal cancer. However, there is little information on how to target this enzyme with either modern medicine or natural products. In this study, we looked at 17-beta-HSD1 as a target for treating CRC development and proliferation using selected plant metabolites from previous studies. Plants are used to produce medicinal and novel bioactive compounds that are used to treat different infection. They primarily demonstrated anti-cancer effects through the regulation of cancer-related proteins, epigenetic factors and reactive oxygenase species. The study utilized Avogadro, ADMET lab 2.0, SWISS-MODEL, AutoDock, and Gromacs. Five lead molecules were chosen from a pool of plant metabolites based on their affinity for the 17-beta-HSD1 enzyme. Furthermore, two bind with high affinity are resveratrol (DG 11.29 kcal/mol) and folate (DG 12.23 kcal/mol) with low Ki values, while the rest binds with moderate affinity. Molecular dynamic simulation results also revealed that the folate-17-beta-HSD complex and reserverol- 17-beta-HSD1 complex maintained a stable conformation until the end of 100 ns. As a result, reserverol and folate could be used as lead molecules to target 17-beta-HSD1 and provide a promising starting point for further in vivo research.Communicated by Ramaswamy H. Sarma.

Evaluation of Intratumoral Response Heterogeneity in Metastatic Colorectal Cancer and Its Impact on Patient Overall Survival: Findings from 10,551 Patients in the ARCAD Database

Metastatic colorectal cancer (mCRC) is a heterogeneous disease that can evoke discordant responses to therapy among different lesions in individual patients. The Response Evaluation Criteria in Solid Tumors (RECIST) criteria do not take into consideration response heterogeneity. We explored and developed lesion-based measurement response criteria to evaluate their prognostic effect on overall survival (OS).

PATIENTS AND METHODS

Patients enrolled in 17 first-line clinical trials, who had mCRC with ≥ 2 lesions at baseline, and a restaging scan by 12 weeks were included. For each patient, lesions were categorized as a progressing lesion (PL: > 20% increase in the longest diameter (LD)), responding lesion (RL: > 30% decrease in LD), or stable lesion (SL: neither PL nor RL) based on the 12-week scan. Lesion-based response criteria were defined for each patient as follows: PL only, SL only, RL only, and varied responses (mixture of RL, SL, and PL). Lesion-based response criteria and OS were correlated using stratified multivariable Cox models. The concordance between OS and classifications was measured using the C statistic.

RESULTS

Among 10,551 patients with mCRC from 17 first-line studies, varied responses were noted in 51.6% of patients, among whom, 3.3% had RL/PL at 12 weeks. Among patients with RL/SL, 52% had stable disease (SD) by RECIST 1.1, and they had a longer OS (median OS (mOS) = 19.9 months) than those with SL only (mOS = 16.8 months, HR (95% CI) = 0.81 (0.76, 0.85), p < 0.001), although a shorter OS than those with RL only (mOS = 25.8 months, HR (95% CI) = 1.42 (1.32, 1.53), p < 0.001). Among patients with SL/PL, 74% had SD by RECIST 1.1, and they had a longer OS (mOS = 9.0 months) than those with PL only (mOS = 8.0 months, HR (95% CI) = 0.75 (0.57, 0.98), p = 0.040), yet a shorter OS than those with SL only (mOS = 16.8 months, HR (95% CI) = 1.98 (1.80, 2.18), p < 0.001). These associations were consistent across treatment regimen subgroups. The lesion-based response criteria showed slightly higher concordance than RECIST 1.1, although it was not statistically significant.

CONCLUSION

Varied responses at first restaging are common among patients receiving first-line therapy for mCRC. Our lesion-based measurement criteria allowed for better mortality discrimination, which could potentially be informative for treatment decision-making and influence patient outcomes.

Progress of research on molecular targeted therapies for colorectal cancer

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

Treatment of BRAF-V600E mutant metastatic colorectal cancer: new insights and biomarkers

INTRODUCTION

The presence of a BRAF-V600E mutation in metastatic colorectal cancer (mCRC) is observed in approximately 12% of cases and is associated with poor prognosis and aggressive disease. Unlike melanoma, the development of successful BRAF blockade in colorectal cancer has been complex. The phase III BEACON trial made significant progress in the development of BRAF inhibitors by establishing encorafenib-cetuximab as the new standard of care for patients with mCRC who have progressed to one or two previous lines of treatment. Nonetheless, not all patients respond to encorafenib-based combinations, and some responses are short-lived. Identifying new strategies to boost antitumor activity and improve survival is paramount.

AREAS COVERED

The development of targeted therapy for BRAF-V600E mCRC starting with BRAF inhibitors as monotherapy through novel combinations with anti-VEGF or anti-PD1 agents to enhance antitumor activity is reviewed, with a particular focus on the development of predictive and prognostic biomarkers.

EXPERT OPINION

There is a crucial need to better understand tumor biology and develop accurate and reliable biomarkers to enhance the antitumor activity of encorafenib-based combinations. The RNF43 mutation is an accurate and reliable predictive biomarker of response, and combinations that target crosstalk between the MAPK pathway, the immune system, and WNT pathways seem promising.

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.

Targeted Therapy in the Palliative Setting of Colorectal Cancer-Survival and Medical Costs

(1) Background: Targeted therapy is used alone or together with chemotherapy in metastatic colorectal cancer. The aim of this study was to assess overall survival and medical costs in a cohort of patients with metastatic colorectal cancer. (2) Methods: Demographic and clinical characteristics of 337 patients and pathological data of colorectal tumors were retrospectively collected in this population-based study. The overall survival and medical costs for patients receiving chemotherapy plus targeted therapy were compared with those for patients receiving chemotherapy only. (3) Results: Patients administered chemotherapy plus targeted therapy were less frail and had more often RAS wild-type tumors but had higher CEA levels than patients receiving chemotherapy only. No prolonged overall survival could be observed in patients receiving palliative targeted therapy. The medical costs for patients undergoing treatment with targeted therapy were significantly higher than for patients treated only with chemotherapy; they were especially higher in the group receiving targeted therapy early than late in the palliative setting. (4) Conclusions: The use of targeted therapy in metastatic colorectal cancer leads to significantly higher medical costs when used early in the palliative setting. No positive effects of the use of targeted therapy could be observed in this study; therefore, we suggest that targeted therapy be used in later lines of palliative therapy in metastatic colorectal cancer.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer (mCRC), published in late 2022, were adapted in December 2022, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with mCRC. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with mCRC representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and the Japanese Society of Medical Oncology (JSMO). The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian countries. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with mCRC across the different countries of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling and age and stage at presentation, coupled with a disparity in the drug approvals and reimbursement strategies, between the different countries.

Current and emerging therapeutic approaches for colorectal cancer: A comprehensive review

Colorectal cancer (CRC) affects 1 in 23 males and 1 in 25 females, making it the third most common cancer. With roughly 608000 deaths worldwide, CRC accounts for 8% of all cancer-related deaths, making it the second most common cause of death due to cancer. Standard and conventional CRC treatments include surgical expurgation for resectable CRC and radiotherapy, chemotherapy, immunotherapy, and their combinational regimen for non-resectable CRC. Despite these tactics, nearly half of patients develop incurable recurring CRC. Cancer cells resist the effects of chemotherapeutic drugs in a variety of ways, including drug inactivation, drug influx and efflux modifications, and ATP-binding cassette transporter overexpression. These constraints necessitate the development of new target-specific therapeutic strategies. Emerging therapeutic approaches, such as targeted immune boosting therapies, non-coding RNA-based therapies, probiotics, natural products, oncolytic viral therapies, and biomarker-driven therapies, have shown promising results in preclinical and clinical studies. We tethered the entire evolutionary trends in the development of CRC treatments in this review and discussed the potential of new therapies and how they might be used in conjunction with conventional treatments as well as their advantages and drawbacks as future medicines.

Hepatectomy versus Chemotherapy for Resectable Colorectal Liver Metastases in Progression after Perioperative Chemotherapy: Expanding the Boundaries of the Curative Intent

Disease progression (PD) at neoadjuvant chemotherapy for patients with colorectal liver metastases (CLMs) is considered a contraindication to hepatic resection. Our aim was to estimate the overall survival (OS) in patients undergoing surgery compared with those treated exclusively with chemotherapy in cases of PD. Patients from a single centre with PD were analyzed and subdivided into two groups: hepatectomy (HEP) versus chemotherapy (CHT). An Inverse Probability Weighting (IPW) was run to balance the baseline differences between the two groups. A Cox regression was carried out on identifying factors predicting mortality. From 2010 to 2020, 105 patients in PD to at least one line of chemotherapy were analyzed. Of these, 27 (25.7%) underwent hepatic resection. After a median follow-up of 30 (IQR 14-46) months, 61.9% were dead. The OS values at 1 and 3 years were 54.4 and 10.6% for CHT, and 95 and 46.8% for HEP (p < 0.001). After IPW, two balanced pseudopopulations were obtained: HEP = 85 and CHT = 103. The OS values at 1 and 3 years were 54.4 and 10.6% for CHT, and 97.8 and 49.3% for HEP (HR 0.256, 95%CI: 0.08-0.78, p = 0.033). After IPW, in the multivariate model, surgery resulted in the only protective variable (HR 0.198, 95%CI: 0.08-0.48, p = 0.0016). Our results show that hepatic resection could offer a chance of a longer OS than the prosecution of chemotherapy only in originally resectable patients.

Targeted Therapy and Personalized Medicine

Targeted therapy and personalized medicine are novel emerging disciplines of cancer research intended for treatment and prevention. One of the most significant advancements in modern oncology is the shift from an organ-centric strategy to a personalized strategy guided by deep molecular analysis. This shift in view, which focuses on the tumour's precise molecular changes, has paved the way for individualized treatment. Researchers and clinicians are using targeted therapies to select the best treatment available based on the molecular characterization of malignant cancer. In the treatment of a cancer, personalized medicine entails the use of genetic, immunological, and proteomic profiling to provide therapeutic alternatives as well as prognostic information about cancer. In this book, targeted therapies and personalized medicine have been covered for specific malignancies, including latest FDA-approved targeted therapies and it also sheds light on effective anti-cancer regimens and drug resistance. This will help to enhance our ability to conduct individualized health planning, make early diagnoses, and choose optimal medications for each cancer patient with predictable side effects and outcomes in a quickly evolving era. Various applications and tools' capacity have been improved for early diagnosis of cancer and the growing number of clinical trials that choose specific molecular targets reflects this predicament. Nevertheless, there are several limitations that must need to be addressed. Hence, in this chapter, we will discuss recent advancements, challenges, and opportunities in personalized medicine for various cancers, with a specific emphasis on target therapies in diagnostics and therapeutics.

Current concepts of anti-EGFR targeting in metastatic colorectal cancer

Anti-EGFR targeting is one of the key strategies in the treatment of metastatic colorectal cancer (mCRC). For almost two decades oncologists have struggled to implement EGFR antibodies in the mCRC continuum of care. Both sidedness and RAS mutational status rank high among the predictive factors for the clinical efficacy of EGFR inhibitors. A prospective phase III trial has recently confirmed that anti-EGFR targeting confers an overall survival benefit only in left sided RAS-wildtype tumors when given in first line. It is a matter of discussion if more clinical benefit can be reached by considering putative primary resistance mechanisms (e.g., HER2, BRAF, PIK3CA, etc.) at this early stage of treatment. The value of this procedure in daily routine clinical utility has not yet been clearly delineated. Re-exposure to EGFR antibodies becomes increasingly crucial in the disease journey of mCRC. Yet re- induction or re-challenge strategies have been problematic as they relied on mathematical models that described the timely decay of EGFR antibody resistant clones. The advent of liquid biopsy and the implementation of more accurate next-generation sequencing (NGS) based high throughput methods allows for tracing of EGFR resistant clones in real time. These displays the spatiotemporal heterogeneity of metastatic disease compared to the former standard radiographic assessment and re-biopsy. These techniques may move EGFR inhibition in mCRC into the area of precision medicine in order to apply EGFR antibodies with the increase or decrease of EGFR resistant clones. This review critically discusses established concepts of tackling the EGFR pathway in mCRC and provides insight into the growing field of liquid biopsy guided personalized approaches of EGFR inhibition in mCRC.

Engaging innate immunity for targeting the epidermal growth factor receptor: Therapeutic options leveraging innate immunity versus adaptive immunity versus inhibition of signaling

The epidermal growth factor receptor (EGFR) is a key player in the normal tissue physiology and the pathology of cancer. Therapeutic approaches have now been developed to target oncogenic genetic aberrations of EGFR, found in a subset of tumors, and to take advantage of overexpression of EGFR in tumors. The development of small-molecule inhibitors and anti-EGFR antibodies targeting EGFR activation have resulted in effective but limited treatment options for patients with mutated or wild-type EGFR-expressing cancers, while therapeutic approaches that deploy effectors of the adaptive or innate immune system are still undergoing development. This review discusses EGFR-targeting therapies acting through distinct molecular mechanisms to destroy EGFR-expressing cancer cells. The focus is on the successes and limitations of therapies targeting the activation of EGFR versus those that exploit the cytotoxic T cells and innate immune cells to target EGFR-expressing cancer cells. Moreover, we discuss alternative approaches that may have the potential to overcome limitations of current therapies; in particular the innate cell engagers are discussed. Furthermore, this review highlights the potential to combine innate cell engagers with immunotherapies, to maximize their effectiveness, or with unspecific cell therapies, to convert them into tumor-specific agents.

ACACB is a novel metabolism-related biomarker in the prediction of response to cetuximab therapy inmetastatic colorectal cancer

Cetuximab is one of the most valuable targeted therapy monoclonal antibodies in the treatment of metastatic colorectal cancer (CRC). However, the mechanisms affecting cetuximab resistance in CRC treatment remain unclear. Metabolism, especially fatty acid metabolism, has been reported to play an important role in tumor treatment. The correlation between cetuximab resistance and metabolism and whether it can be a new biomarker to evaluate the sensitivity of cetuximab in CRC treatment still need to be further explored. In this study, we perform a comprehensive analysis to confirm the relationship between fatty acid metabolism and cetuximab resistance, and the differentially expressed genes (DEGs) related to cetuximab drug resistance in CRC are screened by bioinformatics technology. We find that acetyl-CoA carboxylase beta (ACACB), ADH1C, CES1, MGLL, FMO5, and GPT are the hub DEGs, and ACACB is the most important biomarker among them. In addition, we systematically analyze the role of ACACB in the tumorigenesis of CRC, including tissue expression, CRC cell growth, cetuximab sensitivity, and potential downstream pathways, by using bioinformatics techniques, in vitro experiments and clinical cohort validation. Our results confirm that cetuximab resistance is correlated with metabolism. ACACB can lead to decreased sensitivity to cetuximab in CRC, and its mechanism may be related to EGFR phosphorylation, which could affect the activation of the mTOR/Akt signaling pathway and regulation of CDT1-, cyclin D1-, and p21-related cell cycle modulation.

Real-world overall survival of patients receiving cetuximab in later lines of treatment for metastatic colorectal cancer

Aim: To examine characteristics of and treatment duration and real-world overall survival (rwOS) in patients receiving cetuximab as second-line (2L) or third-line (3L) treatment for metastatic colorectal cancer. Materials & methods: This was a retrospective study of 1096 and 684 patients in 2L and 3L cohorts, respectively. Results: The most common cetuximab-based regimens were cetuximab + folinic acid, fluorouracil and irinotecan (2L: 44%; 3L: 32%) and cetuximab + irinotecan (2L: 28%; 3L: 35%). Kaplan-Meier survival estimates and stepwise Cox regression model analysis demonstrated median treatment duration and rwOS of 3.7 and 14.4 months, respectively, in patients receiving treatment in the 2L cohort. In the 3L cohort, treatment duration was 3.3 months and rwOS was 12.0 months. Conclusion: This large real-world study provides evidence of rwOS in patients with metastatic colorectal cancer receiving cetuximab-based regimens as 2L or 3L treatment.

Efficacy and safety of HER2-targeted inhibitors for metastatic colorectal cancer with HER2-amplified: A meta-analysis

OBJECTIVE

To systematically evaluate the efficacy and safety of human epidermal growth factor receptor 2 (HER2)-targeted inhibitors for metastatic colorectal cancer (mCRC) with HER2-amplified.

METHOD

A systematic search of PubMed, Embase, Cochrane Library, Wan fang, VIP, and the CNKI database was conducted for literature published up to 28 February 2022 on the use of HER2-targeted inhibitors in the treatment of HER2-amplified mCRC. The retrieved articles were screened to determine the final inclusion of literature and extract relevant data, including the objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and incidence of serious adverse events (SAEs) (grade ≥3AEs). In our study, we used merging ratios, means, and 95% confidence intervals (CIs) to describe the efficacy and safety of HER2-targeted inhibitors when treating HER2-amplified mCRC.

RESULTS

The meta-analysis included 8 single-arm clinical trials comprising 258 patients with HER2-amplified mCRC who received second-line or above treatment. In our meta-analysis of mCRC treated with HER2-targeted inhibitors, the ORR and DCR were respectively 29% (95% CI 20-40) and 71% (95% CI 63-78). The median PFS (mPFS) and median OS (mOS) were respectively 4.89 months (95% CI 3.82-5.97) and 13.04 months (95% CI 9.45-16.62). The incidence of SAEs was 12% (95% CI 3-25).

CONCLUSIONS

As the second-line or above treatment, HER2-targeted inhibitors have exhibited good antitumor efficacy and safety in HER2-amplified mCRC patients. Treatment patterns in clinically relevant subpopulations of mCRC patients can be possibly changed using HER2-targeted therapeutic strategies.

The emerging era of personalized medicine in advanced colorectal cancer

Colorectal cancer (CRC) is a genetically heterogeneous disease with its pathogenesis often driven by varying genetic or epigenetic alterations. This has led to a substantial number of patients developing chemoresistance and treatment failure, resulting in a high mortality rate for advanced disease. Deep molecular analysis has allowed for the discovery of key intestinal signaling pathways which impacts colonic epithelial cell fate, and the integral role of the tumor microenvironment on cancer growth and dissemination. Through transitioning pre-clinical knowledge in research into clinical practice, many potential druggable targets within these pathways have been discovered in the hopes of overcoming the roadblocks encountered by conventional therapies. A personalized approach tailoring treatment according to the histopathological and molecular features of individual tumors can hopefully translate to better patient outcomes, and reduce the rate of recurrence in patients with advanced CRC. Herein, the latest understanding on the molecular science behind CRC tumorigenesis, and the potential treatment targets currently at the forefront of research are summarized.

Clinical management of metastatic colorectal cancer in the era of precision medicine

Colorectal cancer (CRC) represents approximately 10% of all cancers and is the second most common cause of cancer deaths. Initial clinical presentation as metastatic CRC (mCRC) occurs in approximately 20% of patients. Moreover, up to 50% of patients with localized disease eventually develop metastases. Appropriate clinical management of these patients is still a challenging medical issue. Major efforts have been made to unveil the molecular landscape of mCRC. This has resulted in the identification of several druggable tumor molecular targets with the aim of developing personalized treatments for each patient. This review summarizes the improvements in the clinical management of patients with mCRC in the emerging era of precision medicine. In fact, molecular stratification, on which the current treatment algorithm for mCRC is based, although it does not completely represent the complexity of this disease, has been the first significant step toward clinically informative genetic profiling for implementing more effective therapeutic approaches. This has resulted in a clinically relevant increase in mCRC disease control and patient survival. The next steps in the clinical management of mCRC will be to integrate the comprehensive knowledge of tumor gene alterations, of tumor and microenvironment gene and protein expression profiling, of host immune competence as well as the application of the resulting dynamic changes to a precision medicine-based continuum of care for each patient. This approach could result in the identification of individual prognostic and predictive parameters, which could help the clinician in choosing the most appropriate therapeutic program(s) throughout the entire disease journey for each patient with mCRC. CA Cancer J Clin. 2022;72:000-000.

Relevance of Fc Gamma Receptor Polymorphisms in Cancer Therapy With Monoclonal Antibodies

Therapeutic monoclonal antibodies (mAbs), including immune checkpoint inhibitors (ICIs), are an important breakthrough for the treatment of cancer and have dramatically changed clinical outcomes in a wide variety of tumours. However, clinical response varies among patients receiving mAb-based treatment, so it is necessary to search for predictive biomarkers of response to identify the patients who will derive the greatest therapeutic benefit. The interaction of mAbs with Fc gamma receptors (FcγR) expressed by innate immune cells is essential for antibody-dependent cellular cytotoxicity (ADCC) and this binding is often critical for their in vivo efficacy. FcγRIIa (H131R) and FcγRIIIa (V158F) polymorphisms have been reported to correlate with response to therapeutic mAbs. These polymorphisms play a major role in the affinity of mAb receptors and, therefore, can exert a profound impact on antitumor response in these therapies. Furthermore, recent reports have revealed potential mechanisms of ICIs to modulate myeloid subset composition within the tumour microenvironment through FcγR-binding, optimizing their anti-tumour activity. The purpose of this review is to highlight the clinical contribution of FcγR polymorphisms to predict response to mAbs in cancer patients.

Efficacy and Safety of Cetuximab Dosing (biweekly vs weekly) in Patients with KRAS Wild-type Metastatic Colorectal Cancer: A Meta-analysis

BACKGROUND

Cetuximab 500 mg/m2 biweekly (Q2W) plus chemotherapy is commonly used and recommended by NCCN guidelines. This meta-analysis compares efficacy and safety between Q2W versus weekly (Q1W) cetuximab dosing.

METHODS

A systematic literature review was performed on Pubmed and RightFind (2007-2017) for patients with KRAS wild-type mCRC who received Q2W or Q1W cetuximab and other treatments. Observational studies and case reports were excluded. Randomized trials comparing Q2W and Q1W dosing, and single-arm trials with only Q2W schedule were included. CRYSTAL, a phase 3 randomized study with Q1W cetuximab dosing was paired with each single-arm study with a Q2W schedule and reweighted to achieve similar demographic/baseline characteristics. Overall survival (OS) and progression-free survival (PFS) with hazard ratios (HR), overall response rate (ORR) with odds ratios, and risk difference of adverse events of special interest (AESI) between Q2W versus Q1W cetuximab were analyzed.

RESULTS

Five phase 2 studies with cetuximab Q2W/Q1W dosing schedules were identified: CECOG (phase 2; Q2W, n = 77; Q1W, n = 75), NORDIC 7.5 (phase 2; Q2W, n = 152) and NORDIC 7 (arm C of phase 3; Q1W, n = 109), CELINE (n = 60), OPTIMIX (n = 99), and APEC (n = 289) all phase 2, Q2W, single-arm studies paired with CRYSTAL Q1W dosing (n = 303). Efficacy was similar between Q2W versus Q1W administration; OS HR = 0.96, 95% confidence interval (CI) [0.89, 1.04]; PFS HR = 0.96, 95% CI [0.87, 1.05]; ORR odds ratio 1.16, 95% CI [0.96, 1.41]. Mean differences (Q2W-Q1W) across AESI rates were not clinically meaningful with no obvious directionality.

CONCLUSION

This meta-analysis demonstrated no significant differences in efficacy and safety between Q2W versus Q1W cetuximab administration in mCRC patients.