Randomized study of FOLFIRI plus either panitumumab or bevacizumab for wild-type KRAS colorectal cancer-WJOG 6210G

Real-world outcomes of FOLFOXIRI plus bevacizumab in patients with metastatic colorectal cancer: the JSCCR-TRIPON study

BACKGROUND

FOLFOXIRI plus bevacizumab is a standard first-line chemotherapy for patients with metastatic colorectal cancer (mCRC). However, due to the severe toxicities, this regimen is not widely used. There is limited data on the real-world efficacy and safety.

METHODS

We conducted a retrospective analysis of clinical data from mCRC patients who received FOLFOXIRI plus bevacizumab as first-line chemotherapy at 31 institutions. The initial dose was standardized according to the TRIBE regimen. Induction therapy was defined as a combination of oxaliplatin, irinotecan, and fluorouracil.

RESULTS

Out of 104 patients who met the criteria, the median age was 58 years (range, 16-72). 81% of patients had an eastern cooperative oncology group performance status (PS) of 0. An initial dose reduction was observed in 63% of patients. The median number of preplanned induction therapy cycles was 12 (range, 4-12). The completion of scheduled induction therapy cycles was observed in 45% of patients, with treatment-related toxicities being the main reason for discontinuation (63%). The median progression-free survival and overall survival were 12.8 months (95% CI, 10.6-15.0) and 27.9 months (95% CI 21.6-34.2), respectively. The objective response rate and disease control rate were 63.7% and 98.9%, respectively. The R0 resection rate was 21.2%. The main grade 3 or higher toxicities were neutropenia (51%), febrile neutropenia (10%), and nausea/vomiting (5%). No treatment-related deaths were observed.

CONCLUSION

In a real-world clinical setting, FOLFOXIRI plus bevacizumab demonstrated efficacy and safety comparable to previous clinical trials.

Real-World Evidence of FOLFIRI Combined with Anti-Angiogenesis Inhibitors or Anti-EGFR Antibodies for Patients with Early Recurrence Colorectal Cancer After Adjuvant FOLFOX/CAPOX Therapy: A Japanese Claims Database Study

BACKGROUND

Oxaliplatin-containing adjuvant regimens (folinic acid, fluorouracil, and oxaliplatin/capecitabine and oxaliplatin [FOLFOX/CAPOX]) are used after curative resection of colorectal cancer (CRC). However, real-world evidence regarding treatment sequences and outcomes in patients with early recurrence CRC after adjuvant chemotherapy is limited.

OBJECTIVE

We aimed to describe the patient characteristics, treatment sequence, and overall duration of second-line (2L) therapy in patients with early recurrence CRC who received adjuvant chemotherapy (FOLFOX/CAPOX) followed by folinic acid, fluorouracil, and irinotecan (FOLFIRI) + anti-angiogenesis drugs (AA) or FOLFIRI + anti-epidermal growth factor receptor (EGFR) antibodies.

METHODS

This retrospective study analyzed Japanese administrative data from November 2014 to March 2023 of adult patients who underwent CRC resection surgery, started FOLFOX/CAPOX ≤3 months (mo) after surgery, and had early CRC recurrence. Early recurrence was defined as initiation of FOLFIRI+AA or FOLFIRI+anti-EGFR antibodies as 2L therapy, ≤12 mo of discontinuing adjuvant chemotherapy. Patient characteristics, treatment sequence, median time to treatment discontinuation (mTTD), i.e., duration between the start and end dates of 2L therapy (Kaplan-Meier method), and factors associated with 2L time to treatment discontinuation constituted the study outcomes (Cox regression model). Subgroup analyses were performed for timing of early CRC recurrence (≤6 mo and 6-12 mo) and tumor sidedness.

RESULTS

Among the 832 selected patients (median age [minimum-maximum] 67 (24-86) years, 56.4% male), CAPOX (71.3%) was more commonly used than FOLFOX (28.7%) as adjuvant therapy. FOLFIRI+AA (72.5%) was used more commonly than FOLFIRI+anti-EGFR antibodies (27.5%) in 2L. AA and anti-EGFR antibodies groups had similar mTTD: 6.2 mo (95% confidence interval 5.8, 6.9) and 6.1 mo (95% confidence interval 5.2, 7.4). Age ≥70 years showed significant association with shorter 2L treatment duration (hazard ratio 1.2, 95% confidence interval 1.0, 1.4; p = 0.03). The AA cohort's mTTD was numerically shorter in the ≤6 mo recurrence subgroup compared with the 6-12 mo recurrence subgroup (6.1 mo vs 8.1 mo); the anti-EGFR antibodies cohort had similar mTTD (5.8 mo vs 6.2 mo). The AA and anti-EGFR antibodies cohorts also had similar mTTD in the left-sided CRC subgroup (6.5 mo vs 6.2 mo), but not in the right-sided subgroup (5.6 mo vs 3.9 mo).

CONCLUSIONS

This is the first administrative data-based real-world evidence on treatment sequence and outcomes for patients with early recurrence CRC treated with FOLFIRI+AAs or FOLFIRI+ anti-EGFR antibodies after adjuvant FOLFOX/CAPOX therapy in Japan. Both regimens had similar TTD, but relapse timing and tumor sidedness may influence their efficacy.

Plasma Angiogenic Factors as Predictors of the Efficacy of Second-line Chemotherapy Combined with Angiogenesis Inhibitors in Metastatic Colorectal Cancer: Results From the GI-SCREEN CRC-Ukit Study

BACKGROUND

The significance of angiogenic factors as predictors of second-line (2L) chemotherapy efficacy when combined with angiogenesis inhibitors for metastatic colorectal cancer (mCRC) remains unestablished.

PATIENTS AND METHODS

In this multicenter prospective observational study, 17 angiogenic factors were analyzed in plasma samples collected at pretreatment and progression stages using a Luminex multiplex assay. Patients who received chemotherapy plus bevacizumab (BEV group), FOLFIRI plus ramucirumab (RAM group), or FOLFIRI plus aflibercept (AFL group) as the 2L treatment were included. Interactions between pretreatment and treatment groups for progression-free survival (PFS), overall survival (OS), and response rate (RR) were assessed using the propensity-score weighted Cox proportional hazards model.

RESULTS

From February 2018 to September 2020, 283 patients were analyzed in the 2L cohort. A strong interaction was observed for PFS between BEV and RAM with HGF, sNeuropilin-1, sVEGFR-1, and sVEGFR-3. Interactions for RR between the BEV and RAM groups were observed for sNeuropilin-1 and sVEGFR-1. Contrarily, OS, PlGF, sVEGFR-1, and sVEGFR-3 differentiated the treatment effect between BEV and AFL. Plasma samples were evaluable for dynamic analysis in 203 patients. At progression, VEGF-A levels significantly decreased in the BEV group and increased in the RAM and AFL groups.

CONCLUSION

The pretreatment plasma sVEGFR-1 and sVEGFR-3 levels could be predictive biomarkers for distinguishing BEV and RAM when combined with chemotherapy in 2L mCRC treatment. Based on the VEGF-A dynamics at progression, selecting RAM or AFL for patients with significantly elevated VEGF-A levels may be a 2L treatment strategy, with BEV considered for the third-line treatment.

CLINICAL TRIAL NUMBER

UMIN000028616.

Effectiveness of bevacizumab in the treatment of metastatic colorectal cancer: a systematic review and meta-analysis

OBJECTIVE

To evaluate the benefit of bevacizumab under the comprehensive treatment strategy and its advantages over other drugs, so as to provide reference for the formulation of clinical plans.

METHODS

As of October 1, 2022, the randomized controlled clinical trials of bevacizumab in combination with metastatic colorectal cancer published in PubMed, Cochrane Library and Medline databases were searched. The odds ratio (OR) and its 95% confidence interval (CI) were used to evaluate the short-term disease control effect and long-term survival of the treatment strategy.

RESULTS

21 RCTs (6665 patients; 3356 patients in the experimental group and 3309 patients in the control group; average age, 55-75 years) were treated with bevacizumab as the experimental group for metastatic colorectal cancer. BEV has stronger anti-tumor activity than the single treatment scheme (OR = 1.30, 95% CI: 1.11-1.52). And Benefits of the BEV group were 0.73 (0.55, 0.96), 1.26 (0.71, 2.24), 1.63 (0.92, 2.87) and 0.07 (0.02, 0.25) compared with CET, VAN, CED and PAN respectively. The disease control of BEV combined therapy was better (OR = 1.36, 95% CI: 1.04-1.78). The same as compared with cediranib (OR = 1.94, 95% CI: 1.06-3.55). However, the long-term prognosis of BEV, including the overall survival (HRs = 0.98, 95% CI: 0.84-1.15) and progression-free survival (HRs = 1.05,95% CI: 0.97-1.13) were not prolonged. The survival benefits of cetuximab and panitumumab were not reflected.

CONCLUSION

The addition of BEV can enhance the anti-tumor ability and disease control, while cetuximab and panitumumab may have stronger ability. However, it did not effectively improve the survival of patients. A more reasonable and effective treatment plan needs more clinical experimental support.

BRAF Non-V600 Mutations in Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the United States. Despite advancements in detection and therapeutic options, patients with metastatic CRC continue to face poor survival rates. The heterogeneity of oncogenic alterations, including BRAF mutations, poses a substantial challenge in identifying optimal treatment approaches. Notably, BRAF non-V600 mutations, encompassing class II and class III mutations, exhibit the distinct patterns of the signaling pathways and responses to targeted therapies compared to BRAF V600 mutations (class I). Nevertheless, the current classification system may underestimate the complexity and heterogeneity of BRAF-mutant CRC. Ongoing clinical trials are actively investigating targeted therapies for BRAF non-V600 mutations, but they are being confronted with patient recruitment obstacles due to the genetic diversity of these alterations. Continued research is needed to refine mutation subtyping, identify effective treatment strategies, and improve outcomes for patients with BRAF non-V600-mutant CRC. Enhancing our understanding and management of this specific subgroup of CRC is crucial for developing personalized treatment approaches and advancing patient care. This manuscript provides a comprehensive overview of the recent advances in and perspectives on BRAF non-V600 alterations in colorectal cancer, including relevant ongoing clinical trials.

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.

Role of plasma angiogenesis factors in the efficacy of first-line chemotherapy combined with biologics in RAS wild-type metastatic colorectal cancer: Results from the GI-SCREEN CRC-Ukit study

BACKGROUND

Several biomarkers have been established for metastatic colorectal cancer (mCRC). We investigated whether plasma angiogenesis factors could predict the efficacy of biologics combined with chemotherapy in first-line (1L) treatment in patients with RAS wild-type mCRC and the dynamics of plasma angiogenesis factors at progression during 1L treatment.

METHODS

In this multicenter prospective observational study, serial plasma samples were prospectively collected at pretreatment and progression stages; 17 plasma angiogenesis factors were analyzed using the multiplex assay with Luminex® technology. Interactions between the pretreatment measurements and treatment groups on progression-free survival (PFS) and overall survival (OS) in patients with RAS wild-type were assessed using the propensity-score weighted Cox proportional hazards model.

RESULTS

From February 2018 to September 2020, 202 patients were enrolled in the 1L cohort; 133 patients had RAS wild-type (chemotherapy plus bevacizumab [BEV group, n = 33] and plus anti-epidermal growth factor receptor monoclonal antibodies [aEGFR group, n = 100]). A trend of strong interaction on PFS was observed for interleukin-8 (IL-8) (p = 0.0752) and soluble vascular cell adhesion molecule-1 (sVCAM-1) (p = 0.0156). Regarding OS, IL-8 (p = 0.0283), soluble vascular endothelial growth factor-receptor-1 (sVEGFR-1) (p = 0.0777) and sVCAM-1 (p = 0.0011) tended to differentiate the treatment effect. In 112 patients, plasma samples were evaluable for dynamic analysis (57 and 55 from the BEV and aEGFR groups, respectively). In the BEV group, six factors significantly increased during progression, whereas two decreased. In the aEGFR group, three factors significantly increased, and six decreased.

CONCLUSION

Pretreatment plasma IL-8 and sVCAM-1 levels could be predictive biomarkers to distinguish BEV and anti-EGFR mAbs when combined with chemotherapy in the 1L treatment of RAS wild-type mCRC. Several plasma angiogenesis factors showed significant change at progression in 1L chemotherapy plus biologics for RAS wild-type mCRC, which are potential biomarkers for selecting an optimal angiogenesis inhibitor in second-line treatment.

Clinical outcomes of chemotherapy-based therapies for previously treated advanced colorectal cancer: a systematic literature review and meta-analysis

PURPOSE

The purpose of this study was to evaluate clinical outcomes of standard therapies in previously treated, advanced colorectal cancer (CRC) patients.

METHODS

A systematic literature review was conducted in Embase, MEDLINE, and CENTRAL databases (January 2000-July 2021), annual oncology conferences (2019-2021), and clinicaltrials.gov to identify studies evaluating the use of licensed interventions in second-line or later settings. The primary outcome of interest was objective response rate (ORR) and secondary outcomes included progression-free survival (PFS) and overall survival (OS). ORR was pooled using the Freeman-Tukey double arcsine transformation. For survival outcomes, published Kaplan-Meier curves for OS and PFS were digitized to re-construct individual patient-level data and pooled following the methodology described by Combescure et al. (2014).

RESULTS

Twenty-three trials evaluating standard chemotherapies with or without targeted therapies across 4,791 advanced CRC patients contributed to our meta-analysis. In the second-line setting, the random effects pooled estimate of ORR was 22.4% (95% confidence interval (CI): 18.0, 27.1), median PFS was 7.0 months (95% CI: 6.4, 7.4), and median OS was 14.9 months (95% CI: 13.6, 16.1). In the third-line or later setting, the random effects pooled estimate of ORR was 1.7% (95% CI: 0.8, 2.7), median PFS was 2.3 months (95% CI: 2.0, 2.8), and median OS was 8.2 months (95% CI: 7.1, 9.1).

CONCLUSION

Standard treatments have limited efficacy in the second-line or later setting with worsening outcomes in later lines. Given the global burden of CRC, further research into novel and emerging therapeutic options following treatment failure is needed.

A phase II study to explore biomarkers for the use of mFOLFOX6/XELOX plus bevacizumab as a first-line chemotherapy in patients with metastatic colorectal cancer (WJOG7612GTR)

BACKGROUND

The purpose of this prospective study was to assess the ability of plasma vascular endothelial growth factor-A short isoforms (pVEGF-Asi) to predict bevacizumab (BV) efficacy and to explore other circulating biomarkers in metastatic colorectal cancer (mCRC) patients treated with modified FOLFOX6/XELOX plus BV (mFOLFOX6/XELOX + BV).

PATIENTS AND METHODS

Pre-treatment plasma samples were collected from 100 mCRC patients receiving first-line chemotherapy with mFOLFOX6/XELOX + BV. The plasma levels of 11 angiogenesis-associated molecules, including pVEGF-Asi and 22 cancer-associated gene mutations in circulating tumor DNA, were analyzed. For the primary endpoint, we assumed that the hazard ratio (HR) for progression-free survival (PFS) calculated using a Cox proportional hazards model was <1.15, comparing patients with a high versus those with a low pVEGF-Asi level divided according to the median pVEGF-Asi value.

RESULTS

The median value of pVEGF-Asi was 37 (range 6.5-262) pg/ml. The HR for PFS between the high and low pVEGF-Asi patient groups was 1.3 [95% confidence interval (CI) 0.8-2.1; log rank, P = 0.25], which was larger than the predefined threshold of 1.15. The multivariate analysis demonstrated that PFS was significantly associated with plasma intercellular adhesion molecule-1 (pICAM-1) (≥190.0 versus <190.0 ng/ml; HR 2.1; 95% CI 1.3-3.5), RAS (mutant versus wild; HR 2.5; 95% CI 1.5-4.3), and FBXW7 (mutant versus wild; HR 2.8; 95% CI 1.2-6.8), whereas overall survival was significantly associated with pICAM-1 (HR 2.0; 95% CI 1.1-3.7) and RAS (HR 2.6; 95% CI 1.5-4.6).

CONCLUSIONS

The addition of BV was unable to compensate for the poor PFS associated with a high pVEGF-Asi level, suggesting that pVEGF-Asi is unlikely to be a good predictive biomarker of the efficacy of mFOLFOX6/XELOX + BV therapy. The clinical significance of circulating ICAM-1, mutant RAS, and mutant FBXW7 levels should be studied further.

Chemotherapy plus panitumumab/cetuximab versus chemotherapy plus bevacizumab in wild-type KRAS/RAS metastatic colorectal cancer: a meta-analysis

OBJECTIVE

It remains controversial which targeted monoclonal antibodies combined with chemotherapy can provide better efficacy in wild-type KRAS/RAS metastatic colorectal cancer (mCRC) patients. Therefore, we used this meta-analysis to assess the latest evidence of clinical outcomes.

MATERIALS AND METHODS

We systematically searched PubMed, Web of Science, Cochrane Library and Embase databases for eligible studies published from database inception to May 2022. RevMan 5.4 was used to conduct the meta-analysis.

RESULTS

11 RCTs involving a total of 3575 patients were included. Meta-analysis showed that EGFR inhibitors significantly prolonged the overall survival (OS) [HR = 0.83, 95%CI (0.73, 0.94), P = 0.003] and overall response rate (ORR) [RR = 1.11, 95%CI (1.05, 1.18), P = 0.0003] compared to VEGF inhibitors in wild-type KRAS/RAS mCRC patients, but no significant difference in progression-free survival (PFS) [HR = 0.96, 95%CI (0.87, 1.07), P = 0.50]. In subgroup analysis, the survival benefit of EGFR inhibitors was limited to first-line treatment.

CONCLUSION

Our study showed that EGFR inhibitors were superior to VEGF inhibitors in wild-type KRAS/RAS mCRC patients, especially in patients with first-line treatment. However, subsequent large sample, multi-center RCTs are needed to further verify our conclusions.

Economic evaluation of encorafenib with cetuximab in patients with BRAF V600E-mutant metastatic colorectal cancer in France: a cost-effectiveness analysis using data from the BEACON CRC randomised controlled trial

OBJECTIVE

The BEACON CRC randomised controlled trial (NCT02928224) in BRAF-mutant metastatic colorectal cancer (mCRC) patients showed improved overall survival for the combination treatment of encorafenib (BRAF inhibitor) with cetuximab (EGFR inhibitor) compared with cetuximab with chemotherapy (FOLFIRI (folinic acid, fluorouracil and irinotecan) or irinotecan). We aimed to evaluate the cost-effectiveness of encorafenib with cetuximab in adult patients with BRAF-mutant mCRC after prior systemic therapy, from the perspective of the French healthcare system.

DESIGN

A partitioned survival analysis model was developed to assess the cost-effectiveness of encorafenib with cetuximab using data from BEACON CRC (encorafenib with cetuximab and cetuximab with FOLFIRI or irinotecan). For two further comparator treatments (FOLFIRI alone and bevacizumab with FOLFIRI), a systemic literature review identified appropriate clinical trial data for indirect comparison. Piecewise modelling extrapolation was used to fulfil a lifetime horizon in the model. A discount rate of 2.5% was used. Treatment-emergent adverse events ≥grade 3 with an incidence of ≥2% were included, as well as relative dose intensity and utility values.

OUTCOME MEASURES

The effectiveness outcomes of the model were expressed in terms of incremental life years gained and incremental quality-adjusted life years (QALY) gained. The cost-effectiveness of encorafenib with cetuximab was assessed using the incremental cost-effectiveness ratio (ICER). Results were presented probabilistically to account for parametric uncertainty. Deterministic and scenario analyses were conducted.

RESULTS

The ICER for encorafenib with cetuximab versus cetuximab with FOLFIRI or irinotecan, FOLFIRI alone and bevacizumab with FOLFIRI was €69 823/QALY, €70 421/QALY and €72 336/QALY, respectively. Encorafenib with cetuximab was considered cost-effective compared with the three comparators at a willingness to pay threshold of €90 000/QALY, with probabilities of being cost-effective of 89.8%, 98.2% and 86.4%, respectively.

CONCLUSIONS

This analysis showed encorafenib with cetuximab to be a cost-effective treatment in mCRC patients with a BRAF V600E mutation.

The Validity of Surrogate Endpoints in Sub Groups of Metastatic Colorectal Cancer Patients Defined by Treatment Class and KRAS Status

Background and Aim: Findings from the literature suggest that the validity of surrogate endpoints in metastatic colorectal cancer (mCRC) may depend on a treatments' mechanism of action. We explore this and the impact of Kirsten rat sarcoma (KRAS) status on surrogacy patterns in mCRC. Methods: A systematic review was undertaken to identify randomized controlled trials (RCTs) for pharmacological therapies in mCRC. Bayesian meta-analytic methods for surrogate endpoint evaluation were used to evaluate surrogate relationships across all RCTs, by KRAS status and treatment class. Surrogate endpoints explored were progression free survival (PFS) as a surrogate endpoint for overall survival (OS), and tumour response (TR) as a surrogate for PFS and OS. Results: 66 RCTs were identified from the systematic review. PFS showed a strong surrogate relationship with OS across all data and in subgroups by KRAS status. The relationship appeared stronger within individual treatment classes compared to the overall analysis. The TR-PFS and TR-OS relationships were found to be weak overall but stronger within the Epidermal Growth Factor Receptor + Chemotherapy (EGFR + Chemo) treatment class; both overall and in the wild type (WT) patients for TR-PFS, but not in patients with the mutant (MT) KRAS status where data were limited. Conclusions: PFS appeared to be a good surrogate endpoint for OS. TR showed a moderate surrogate relationship with PFS and OS for the EGFR + Chemo treatment class. There was some evidence of impact of the mechanism of action on the strength of the surrogacy patterns in mCRC, but little evidence of the impact of KRAS status on the validity of surrogate endpoints.

Circulating tumour DNA and its clinical utility in predicting treatment response or survival in patients with metastatic colorectal cancer: a systematic review and meta-analysis

BACKGROUND

We investigate the current knowledge on circulating tumour DNA (ctDNA) and its clinical utility in predicting outcomes in patients with metastatic colorectal cancer (mCRC).

METHODS

PubMed, Embase, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials were searched. Last search 16/12/2020. We included studies on patients with mCRC reporting the predictive or prognostic value of ctDNA. We performed separate random-effects meta-analyses to investigate if baseline ctDNA and early changes in ctDNA levels during treatment were associated with survival. The risk of bias was assessed according to the Quality in Prognosis Studies tool.

RESULTS

Seventy-one studies were included with 6930 patients. Twenty-four studies were included in meta-analyses. High baseline ctDNA level was associated with short progression-free survival (PFS) (HR = 2.2; 95% CI 1.8-2.8; n = 509) and overall survival (OS) (HR = 2.4; 95% CI 1.9-3.1; n = 1336). A small or no early decrease in ctDNA levels during treatment was associated with short PFS (HR = 3.0; 95% CI 2.2-4.2; n = 479) and OS (HR = 2.8; 95% CI 2.1-3.9; n = 583). Results on clonal evolution and lead-time were inconsistent. A majority of included studies (n = 50/71) had high risk of bias in at least one domain.

CONCLUSIONS

Plasma ctDNA is a strong prognostic biomarker in mCRC. However, true clinical utility is lacking.

Safety Assessment on Serious Adverse Events of Targeted Therapeutic Agents Prescribed for RAS Wild-Type Metastatic Colorectal Cancer: Systematic Review and Network Meta-Analysis

Despite substantially elevated risk of serious adverse events (SAEs) from targeted therapy in combination with chemotherapy, comprehensive pharmacovigilance research is limited. This study aims to systematically assess SAE risks of commonly prescribed targeted agents (bevacizumab, cetuximab, and panitumumab) in patients with rat sarcoma viral oncogene homolog (RAS) wild-type metastatic colon cancer. Keyword searches of Cochrane Library, Clinical Key and MEDLINE were conducted per PRISMA-NMA guidelines. Frequentist network meta-analysis was performed with eight randomized controlled trials to compare relative risk (RR) of 21 SAE profiles. The risks of hematological, gastrointestinal, neurological SAE were insignificant among targeted agents (p > 0.05). The risk of serious hypertension was substantially elevated in bevacizumab-based chemotherapy (p < 0.05), whereas panitumumab-based chemotherapy had markedly elevated risk of serious thromboembolism (RR 3.65; 95% CI 1.30−10.26). Although both cetuximab and panitumumab demonstrated increased risk of serious dermatological and renal toxicities, panitumumab-based chemotherapy has relatively higher risk of skin toxicity (RR 15.22; 95% CI 7.17−32.35), mucositis (RR 3.18; 95% CI 1.52−6.65), hypomagnesemia (RR 20.10; 95% CI 5.92−68.21), and dehydration (RR 2.81; 95% CI 1.03−7.67) than cetuximab-based chemotherapy. Thus, further studies on risk stratification and SAE management are warranted for safe administration of targeted agents.

Multicenter, single-arm, phase II study of the continuous use of panitumumab in combination with FOLFIRI after FOLFOX for RAS wild-type metastatic colorectal cancer - Exploratory sequential examination of acquired mutations in circulating cell-free DNA

This multicenter single-arm, phase II study evaluated the efficacy and safety of uninterrupted panitumumab usage combined with cytotoxic doublets for unresectable/metastatic colorectal cancer (mCRC). Additionally, clinical value of the RAS/BRAF mutation status in circulating cell-free DNA (ccfDNA) was evaluated; this evaluation was measured independently of the protocol treatment. Eligible patients with RAS wild-type mCRC who had received the first-line panitumumab plus FOLFOX treatment were recruited and administered continuous panitumumab combined with FOLFIRI. Progression-free survival (PFS) at 6 months was the primary endpoint, with threshold and expected values of 35% and 50%, respectively. In total, 54 patients were enrolled between October 2017 and October 2019. The crude 6-month PFS rate was 37.0%, with a 4.8-month median PFS. The response rate and disease control rate were 16.7 % and 50.0%, respectively. Notably, of the 54 participants, 17 showed RAS/BRAF mutations until the end of the protocol treatment, and of the 22 patients with progressive disease as their best response, 10 possessed RAS/BRAF mutations in their plasma ccfDNA at baseline. The median PFS significantly differed among patients harboring tumors with BRAF and RAS mutations and those with wild-type tumors. In conclusion, this study failed to show the expected efficacy of the continuous panitumumab use in the second-line treatment. Liquid biopsy discriminated the duration of PFS according to the mutation status. The effectiveness of continuous treatment with panitumumab should be evaluated in patients with RAS/BRAF wild-type mCRC determined by liquid biopsy at the start of the second-line treatment.

Comparative Effectiveness of Bevacizumab versus Cetuximab in Metastatic Colorectal Cancer Patients without Primary Tumor Resection

Primary tumor resection may be unfeasible in metastatic colorectal cancer. We determined the effects of bevacizumab and cetuximab therapies on survival or conversion surgery in patients with metastatic colorectal cancer who did not undergo primary tumor resection. This retrospective cohort study enrolled 8466 patients who underwent first-line bevacizumab- or cetuximab-based therapy. We analyzed the data of both therapies in patients who did not undergo primary tumor resection. Overall survival after targeted therapy plus chemotherapy was assessed. The groups were matched using propensity score matching and weighting. Cetuximab resulted in lower mortality than bevacizumab (hazard ratio (HR) = 0.75); however, it did not have the same effect in patients that underwent primary tumor resection (HR = 0.95) after propensity score weighting. Among patients treated with targeted agents, primary tumor resection was associated with lower mortality among those who received both bevacizumab (HR = 0.60) and cetuximab (HR = 0.75). Among patients that did not undergo primary tumor resection, multivariable analysis for conversion surgery showed that the cetuximab group (HR = 1.82) had a significantly higher metastasectomy rate. In these patients, cetuximab-based therapy was associated with significantly better survival compared with bevacizumab-based therapy. Cetuximab also yielded a higher conversion surgery rate. These findings demonstrate the importance of stratification by primary tumor resection in the application of current treatment guidelines and initiation of future clinical trials.

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

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

Resource Oriented Decision Making for Treatment of Metastatic Colorectal Cancer (mCRC) in a Lower-Middle Income Country: Egyptian Foundation of Medical Sciences (EFMS) Consensus Recommendations 2020

PURPOSE

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide and the second cause of cancer related mortality. Treatment options for patients with metastatic CRC (mCRC) expanded during the last two decades, with introduction of new chemotherapeutic and targeted agents. Egypt is a lower middle-income country; Egyptian health care system is fragmented with wide diversity in drug availability and reimbursement policies across different health care providing facilities. We report the results of consensus recommendations for treatment of patients with metastatic colorectal cancer developed by Egyptian Foundation of Medical Sciences (EFMS), aiming to harmonize clinical practice through structured expert consensus-based recommendations consistent with the national status. EFMS recommendations could be utilized in other countries with similar economic status.

METHODS

EFMS recommendations were developed using a modified Delphi process, with three rounds of voting till the final recommendations were approved. A non-systematic review of literature was conducted before generating the provisional statements. Content experts were asked to vote on some recommendations in two different resource groups (restricted resources and non-restricted resources). External review board of experts from a low income and lower-middle countries voted on the applicability of EFMS recommendations in their countries.

RESULTS

The current recommendations highlighted the discrepancy in health care between restricted and non-restricted resources with expected survival loss and quality of life deterioration. Access to targeted agents in first line is very limited in governmental institutions, and no access to agents approved for third line in patients who failed oxaliplatin and irinotecan containing regimens for patients treated in restricted resource settings.

CONCLUSION

Management of mCRC in developing countries is a challenge. The currently available resource-stratified guidelines developed by international cancer societies represent a valuable decision-making tool, adaptation to national status in each country based on healthcare system status is required.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

SYSTEMATIC REVIEW REGISTRATION

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

Optimal Sequence and Second-Line Systemic Treatment of Patients with RAS Wild-Type Metastatic Colorectal Cancer: A Meta-Analysis

Although several sequential therapy options are available for treating patients with RAS wild-type (WT) metastatic colorectal cancer (mCRC), the optimal sequence of these therapies is not well established. A systematic review and meta-analysis of 13 randomized controlled trials and 4 observational studies were performed, resulting from a search of the Cochrane Library, PubMed, and Embase databases. Overall survival (OS) did not differ significantly in patients with RAS-WT failure who were administered a second-line regimen of changed chemotherapy (CT) plus anti-epidermal growth factor receptor (EGFR) versus only changed CT, changed CT plus bevacizumab versus changed CT plus anti-EGFR, or changed CT versus maintaining CT plus anti-EGFR after first-line therapy with CT, plus bevacizumab. However, OS was significantly different with a second-line regimen that included changed CT plus bevacizumab, versus only changing CT. Analysis of first-line therapy with CT plus anti-EGFR for treatment of RAS-WT mCRC indicated that second-line therapy of changed CT plus an anti-EGFR agent resulted in better outcomes than changing CT without targeted agents. The pooled data study demonstrated that the optimal choice of second-line treatment for improved OS was an altered CT regimen with retention of bevacizumab after first-line bevacizumab failure. The best sequence for first-to-second-line therapy of patients with RAS-WT mCRC was cetuximab-based therapy, followed by a bevacizumab-based regimen.

Second-line chemotherapy after early disease progression during first-line chemotherapy containing bevacizumab for patients with metastatic colorectal cancer

Background

The ML18174 study, which showed benefits of bevacizumab (BEV) continuation beyond progression (BBP) for metastatic colorectal cancer (mCRC), excluded patients with first-line progression-free survival (PFS) shorter than 3 months. The present study was conducted to evaluate the efficacy of second-line chemotherapy after early disease progression during first-line chemotherapy containing bevacizumab.

Methods

The subjects of this study were mCRC patients who experienced disease progression < 100 days from commencement of first-line chemotherapy containing BEV initiated between Apr 2007 and Dec 2016. Second-line chemotherapy regimens were classified into two groups with and without BEV/other anti-angiogenic agents (BBP and non-BBP) and efficacy and safety were compared using univariate and multivariate analysis.

Results

Sixty-one patients were identified as subjects of this study. Baseline characteristics were numerically different between BBP (n = 37) and non-BBP (n = 25) groups, such as performance status (0–1/> 2/unknown: 89/8/3 and 56/40/4%), RAS status (wild/mutant/unknown: 32/54/16 and 76/16/8%). Response rate was 8.6% in BBP group and 9.1% in non-BBP group (p = 1.00). Median PFS was 3.9 months in BBP group and 2.8 months in non-BBP group (HR [95%CI]: 0.79 [0.46–1.34], p = 0.373, adjusted HR: 0.87 [0.41–1.82], p = 0.707). Median overall survival was 8.5 months in BBP group and 5.4 months in non-BBP group (HR 0.66 [0.38–1.12], p = 0.125, adjusted HR 0.53 [0.27–1.07], p = 0.078).

Conclusion

In mCRC patients who experienced early progression in first-line chemotherapy, second-line chemotherapy showed poor clinical outcomes regardless use of anti-angiogenic agents.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08890-6.

The best strategy for metastatic colorectal cancer (mCRC) patients in second-line treatment: A network meta-analysis

BACKGROUND

Varieties of systemic treatments in second-line treatment for metastatic colorectal cancer (mCRC) patients have showed an improvement on survival. In this study, we performed a systematic review with a pairwise and bayesian network meta-analysis to rank the best strategy for mCRC patients in second-line treatment.

METHODS

A systematic literature search through 2007 was performed to evaluate the association between several treatment combinations and overall survival (OS), progression-free survival (PFS) and disease control rate (DCR) in mCRC patients. Data were carried out and pooled into a statistical indirect comparison with Bayesian network meta-analysis (NMA).

RESULTS

10 trials totally comprised 4183 patients were included in our study. In NMA, For PFS, Doublet+Bev showed benefits in comparing with Doublet, Doulblet+placebo and Doublet+Ramucirumab. Also, Doublet+Aflibercept demonstrated its superiority in comparing with Doulblet+placebo. For OS, Doublet+Bev represented its superiority when comparing with Double and Doublet+placebo. Doublet+Aflibercept and Doublet+Ramucirumab also done well when opposed to Doublet+placebo. For DCR, Doublet+bev showed unique superiority when compared with Doublet, And Doublet+targeted agent did not represent benefits to each other in DCR. Doublet+bev ranked highest in terms of PFS, OS and DCR followed by Doublet+panitumumab, Doublet+placebo was the lowest in terms of PFS and OS.

CONCLUSIONS

Our study shows that Doublet+Bev has the major probability to provide an improvement of survival in patients with mCRC.

Shared decision-making and patient decision aids in choosing first-line targeted therapy for metastatic colorectal cancer in Taiwan

INTRODUCTION

In Taiwan, given the discrepancy between current treatment guidelines and reimbursement options, patients might require a tool to support their decision-making process when selecting a regimen for metastatic colorectal cancer, especially therapeutic strategies, and subsequent costs, along with efficacy and safety outcomes. Therefore, we developed a patient decision aid (PDA) to support patients in choosing between treatment options recommended based on the current evidence and those reimbursed by the Taiwanese National Health Insurance.

METHODS

By carefully reviewing the updated data and then interpreting the clinical tool, we conducted a needs assessment using a serial questionnaire to test for a step-by-step adjustment of the PDA.

RESULTS

Patients, their relatives, and medical team members were most concerned about outcomes, such as overall survival, progression-free survival, objective response rate, tumor shrinkage to resectable status, total medical cost, severe gastrointestinal perforation, and severe skin reaction. After a serial alpha test for quality, we performed quantitative evaluation and beta tests, revealing average scores of more than 4 points (on a scale of 1-5) for both perceptibility and utility.

CONCLUSIONS

The present findings suggest that PDAs are useful and supplement the shared decision-making practice, helping patients make decisions about preferences and consider the pros and cons of treatment regimens, along with insurance reimbursement options.

Treatments after first progression in metastatic colorectal cancer. A literature review and evidence-based algorithm

Prolonging survival, achieving symptoms palliation and preserving quality of life are the primary therapeutic goals of treatments administered after disease progression in mCRC. Even if the impact of these therapies on the prognosis of affected patients is less relevant than the impact of the upfront treatment, tailoring the optimal second-line therapy is increasingly important. Several therapeutic options are available, and different factors including not only patient- and disease-related characteristics, but also the first-line treatment received (i.e., type, timing of disease progression, observed outcome and reported toxicities) may drive this choice. Herein, we describe the current state of the art in the landscape of treatments after progression in mCRC. Based on a critical review of the literature, we built a patient-oriented therapeutic algorithm, aiming to guide clinicians in their daily decision-making.

BIG BANG study (EPOC1703): multicentre, proof-of-concept, phase II study evaluating the efficacy and safety of combination therapy with binimetinib, encorafenib and cetuximab in patients with BRAF non-V600E mutated metastatic colorectal cancer

Background

While the BRAF V600E mutation occurs in 5%–15% of metastatic colorectal cancer (mCRC), BRAF non-V600E mutations were recently reported to range from 1.6% to 5.1%. We have previously reported that BRAF non-V600E mutations could have a negative impact on efficacy outcomes as well as BRAF V600E mutation for antiepidermal growth factor receptor (EGFR) antibody treatment for pretreated patients with mCRC. Recently, simultaneous inhibitions of mitogen-activated protein kinase kinase (MEK), BRAF and EGFR exhibited relevant antitumour activities in patients with BRAF V600E mutant and also in BRAF non-V600E mutant but only in the preclinical model.

Trial design

The BIG BANG (study is a multicentre, phase II study to assess the efficacy, safety and proof of concept of the combinations of binimetinib+encorafenib+cetuximab in patients with BRAF non-V600E mutated mCRC, identified by either tumour tissue (tumour tissue group) or blood samples (liquid biopsy group). Key eligibility criteria include Eastern Cooperative Oncology Group Performance Status of ≤1, mCRC with BRAF non-V600E mutant and RAS wild type, refractory or intolerant to at least one fluoropyrimidine-based regimen and no prior history of regorafenib, and no prior history of anti-EGFR antibody treatment (primary analysis cohort and liquid biopsy cohort) or refractory to prior anti-EGFR antibody treatment in patients with class 3 BRAF mutations (anti-EGFR antibody refractory class three cohort). Enrolled patients receive binimetinib (45 mg, two times per day), encorafenib (300 mg, once a day) and cetuximab (initially 400 mg/m² and subsequently 250 mg/m², once per week). The primary endpoint is the confirmed objective response rate in the primary analysis cohort.

Trial registration numbers

UMIN000031857 and 000031860.

Early Tumor Shrinkage and Depth of Response in the Second-Line Treatment for KRAS exon2 Wild-Type Metastatic Colorectal Cancer: An Exploratory Analysis of the Randomized Phase 2 Trial Comparing Panitumumab and Bevacizumab in Combination with FOLFIRI (WJOG6210G)

BACKGROUND

Predictive markers for the clinical outcomes of second-line treatment in patients with metastatic colorectal cancer (mCRC) remain unclear.

OBJECTIVE

This retrospective biomarker study was conducted to explore predictive markers for patients with KRAS exon 2 wild-type mCRC who were treated with FOLFIRI plus panitumumab (Pani) or bevacizumab (Bev) in the WJOG6210G trial.

PATIENTS AND METHODS

The associations of early tumor shrinkage (ETS), tumor location, and VEGF-D with progression-free survival (PFS) and overall survival (OS) were analyzed using a Cox proportional hazards model. Spearman's correlation coefficient was used to analyze the association of depth of response (DpR) with PFS and OS. Serum VEGF-D levels were measured in samples collected before treatment using magnetic bead panel Milliplex xMAP kits.

RESULTS

In total, 101 patients (Pani, n = 49; Bev, n = 52) were enrolled in this study. Patients with ETS had longer PFS (Pani: hazard ratio (HR) 0.40, P = 0.009; Bev: HR 0.078, P = 0.0002) and OS (Pani: HR 0.49, P = 0.044; Bev: HR 0.35, P = 0.048) than patients without ETS. The DpR was moderately correlated with PFS and OS in Pani (rs = 0.75, P < 0.001; rs = 0.60, P < 0.001) and Bev groups (rs = 0.68, P < 0.001; rs = 0.44, P = 0.002). No significant differences were observed in PFS and OS between the two treatment groups even if in left-sided tumors. No significant interaction between VEGF-D levels and treatment was observed in PFS and OS.

CONCLUSIONS

ETS and DpR serve as surrogate markers of PFS and OS in the second-line treatment with FOLFIRI plus targeted agent for mCRC.

Combining Correlated Outcomes and Surrogate Endpoints in a Network Meta-Analysis of Colorectal Cancer Treatments

This study aimed to investigate the efficacy and safety of systemic therapies in the treatment of unresectable advanced or metastatic colorectal cancer. Predicted hazard ratios (HRs) and their 95% credible intervals (CrIs) for overall survival (OS) were calculated from the odds ratio (OR) for the overall response rate and/or HR for progression-free survival using multivariate random effects (MVRE) models. We performed a network meta-analysis (NMA) of 49 articles to compare the efficacy and safety of FOLFOX/FOLFIRI±bevacizumab (Bmab)/cetuximab (Cmab)/panitumumab (Pmab), and FOLFOXIRI/CAPEOX±Bmab. The NMA showed significant OS improvement with FOLFOX, FOLFOX+Cmab, and FOLFIRI+Cmab compared with that of FOLFIRI (HR = 0.84, 95% CrI = 0.73-0.98; HR = 0.76, 95% CrI = 0.62-0.94; HR = 0.80, 95% CrI = 0.66-0.96, respectively), as well as with FOLFOX+Cmab and FOLFIRI+Cmab compared with that of FOLFOXIRI (HR = 0.69, 95% CrI = 0.51-0.94 and HR = 0.73, 95% CrI = 0.54-0.97, respectively). The odds of adverse events grade ≥3 were significantly higher for FOLFOX+Cmab vs. FOLFIRI+Bmab (OR = 2.34, 95% CrI = 1.01-4.66). Higher odds of events were observed for FOLFIRI+Pmab in comparison with FOLFIRI (OR = 2.16, 95% CrI = 1.09-3.84) and FOLFIRI+Bmab (OR = 3.14, 95% CrI = 1.51-5.89). FOLFOX+Cmab and FOLFIRI+Bmab showed high probabilities of being first- and second-line treatments in terms of the efficacy and safety, respectively. The findings of the efficacy and safety comparisons may support the selection of appropriate treatments in clinical practice. PROSPERO registration: CRD42020153640.

Efficacy of Panitumumab and Cetuximab in Patients with Colorectal Cancer Previously Treated with Bevacizumab; a Combined Analysis of Individual Patient Data from ASPECCT and WJOG6510G

Background: Phase-III ASPECCT and randomised phase-II WJOG6510G trials demonstrated the noninferiority of panitumumab, when compared with cetuximab, for overall survival in patients with chemotherapy-refractory wild-type KRAS exon 2 metastatic colorectal cancer. Methods: The subgroup that received bevacizumab either prior to panitumumab or cetuximab monotherapy (ASPECCT) or in combination with irinotecan (WJOG6510G) was included. Multivariate Cox models were created, including the treatment arms as covariates together with patient, disease and treatment characteristics. Results: We included 185 and 189 patients in the panitumumab and cetuximab arms, respectively. The median overall survival was 12.8 and 10.1 months [p = 0.0031; log-rank test, stratified by trial; hazard ratio (HR), 0.72; 95% confidence interval (CI), 0.58–0.90], and the median progression-free survival was 4.7 and 4.1 months, in the panitumumab and cetuximab arms, respectively (p = 0.0207; HR, 0.79; 95% CI, 0.64–0.97). The treatment regimen was an independent prognostic factor of overall survival (adjusted HR, 0.69; 95% CI, 0.54–0.87; p = 0.0013). Conclusions: Panitumumab significantly prolonged the overall survival and progression-free survival, when compared with cetuximab in the cohort that previously received bevacizumab in the included studies. Clinical Trial Registration: ASPECCT trial registered with ClinicalTrials.gov (NCT01001377) and WJOG6510G trial registered with UMIN-CTR (UMIN000006643).

Efficacy of bevacizumab-containing chemotherapy in metastatic colorectal cancer and CXCL5 expression: Six case reports

BACKGROUND

In metastatic colorectal cancer (mCRC), the anti-vascular endothelial growth factor drug bevacizumab (BVZ) plus chemotherapy significantly improves progression-free survival compared to chemotherapy (CT) alone. This benefit is not, however, observed in all patients. While increased chemokine CXCL5 gene expression promoting angiogenesis has been proposed as a prognostic mCRC biomarker, few studies have examined its relationship with drug efficacy. This study sought to analyze tumor CXCL5 gene expression in six patients with different efficacy of BVZ-containing CT in terms of the tumor response to treatment.

CASE SUMMARY

We report six cases of stage IV KRAS-mutated mCRC. Patients were given first line treatment with BVZ-containing chemotherapy in University Hospital of Fuenlabrada. The six patients differed in terms of primary tumor location (right/left side), tumor burden (mostly hepatic and peritoneal disease) and clinical disease course. Before treatment onset, total RNA was isolated from paraffinated tumor biopsy specimens and CXCL5 gene expression quantified through conventional RT-qPCR procedures. Our main finding was that CXCL5 expression levels were several times higher in three patients with lower progression free survival (under 6 mo) from the start of treatment.

CONCLUSION

A higher expression of CXCL5 was observed in the three patients showing worse tumor response to treatment.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer

The number of deaths from colorectal cancer in Japan continues to increase. Colorectal cancer deaths exceeded 50,000 in 2016. In the 2019 edition, revision of all aspects of treatments was performed, with corrections and additions made based on knowledge acquired since the 2016 version (drug therapy) and the 2014 version (other treatments). The Japanese Society for Cancer of the Colon and Rectum guidelines 2019 for the treatment of colorectal cancer (JSCCR guidelines 2019) have been prepared to show standard treatment strategies for colorectal cancer, to eliminate disparities among institutions in terms of treatment, to eliminate unnecessary treatment and insufficient treatment and to deepen mutual understanding between healthcare professionals and patients by making these guidelines available to the general public. These guidelines have been prepared by consensuses reached by the JSCCR Guideline Committee, based on a careful review of the evidence retrieved by literature searches and in view of the medical health insurance system and actual clinical practice settings in Japan. Therefore, these guidelines can be used as a tool for treating colorectal cancer in actual clinical practice settings. More specifically, they can be used as a guide to obtaining informed consent from patients and choosing the method of treatment for each patient. Controversial issues were selected as clinical questions, and recommendations were made. Each recommendation is accompanied by a classification of the evidence and a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSCCR guidelines 2019.

Targeting EGFR and RAS/RAF Signaling in the Treatment of Metastatic Colorectal Cancer: From Current Treatment Strategies to Future Perspectives

The epidermal growth factor receptor (EGFR) and RAS/RAF signaling pathway plays pivotal roles in tumor progression via proliferation, survival, invasion, and immune evasion. Two anti-EGFR monoclonal antibodies, cetuximab and panitumumab, have become essential components in the treatment of patients with metastatic colorectal cancer (mCRC). Treatment with these anti-EGFR antibodies has shown definite benefits when administered in all treatment lines and is strongly recommended as the preferred regimen to prolong survival, especially when administered in the first- and third-lines. Recent efforts have revealed not only mechanisms responsible for resistance to anti-EGFR antibodies, including expanded RAS mutations as a negative predictive biomarker, but also the possibility of continuing anti-EGFR antibody treatment in combination with chemotherapy. Furthermore, the challenges associated with the pharmaceutical development of treatments for patients with mutant-type BRAF mCRC are ongoing. In this review, we provide an overview of the EGFR and RAS/RAF signaling pathway and antitumor activity, focusing on practical aspects such as established treatments including patient selection, treatment strategies, and future perspectives for drug development targeting the EGFR and RAS/RAF signaling pathway.

ctDNA detected by ddPCR reveals changes in tumour load in metastatic malignant melanoma treated with bevacizumab

Bevacizumab is included in an increasing number of clinical trials. To find biomarkers to predict and monitor treatment response, cancer and angiogenesis relevant mutations in tumour and circulating tumour DNA (ctDNA) were investigated in 26 metastatic melanoma patients treated with bevacizumab. Patients with >1% BRAF/NRAS ctDNA at treatment start had significantly decreased progression free survival (PFS) and overall survival (OS) (PFS: p = 0.019, median 54 vs 774 days, OS: p = 0.026, median 209 vs 1064 days). Patients with >1% BRAF/NRAS ctDNA during treatment showed similar results (PFS: p = 0.002, OS: p = 0.003). ≤1% BRAF/NRAS ctDNA and normal lactate dehydrogenase (LDH) levels both significantly predicted increased response to treatment, but BRAF/NRAS ctDNA was better at predicting response compared to LDH at treatment start (OR 16.94, p = 0.032 vs OR 4.57, p = 0.190), and at predicting PFS (HR 6.76, p = 0.002) and OS (HR 6.78, p = 0.002) during therapy. ctDNA BRAF p.V600D/E/K and NRAS p.G12V/p.Q61K/L/R were better biomarkers for response prediction than TERT promoter mutations (OR 1.50, p = 0.657). Next generation sequencing showed that all patients with ≥2 mutations in angiogenesis-relevant genes had progressive disease, but did not reveal other biomarkers identifying responders. To conclude, ctDNA and LDH are useful biomarkers for both monitoring and predicting response to bevacizumab.

Tumor sidedness and efficacy of first-line therapy in patients with RAS/BRAF wild-type metastatic colorectal cancer: A network meta-analysis

We conducted a systemic search of several databases for randomized controlled trials (RCTs) that reported efficacy and safety outcomes of drugs for left-sided and right-sided metastatic colorectal cancer (mCRC), to identify the best available treatment. A network meta-analysis with mixed comparisons was created to interpret the best treatment option using the surface under the cumulative ranking curve. In the left-sided rat sarcoma (RAS) wild-type (WT) mCRC patients, bevacizumab, panitumumab, or cetuximab with chemotherapy groups showed a significantly better objective response rate than the chemotherapy alone group. The progression-free survival (PFS) and overall survival were better with panitumumab or cetuximab with chemotherapy than with chemotherapy alone. In the right-sided RAS WT mCRC patients, PFS for bevacizumab with chemotherapy was significantly better than that for cetuximab with chemotherapy. Cetuximab, closely followed by panitumumab, is the most effective treatment in left-sided RAS WT mCRC. Bevacizumab is more effective in right-sided mCRC.

Barcode sequencing identifies resistant mechanisms to epidermal growth factor receptor inhibitors in circulating tumor DNA of lung cancer patients

Most patients with epidermal growth factor receptor (EGFR) mutation‐positive non‐small cell lung cancer (NSCLC) will inevitably develop acquired resistance induced by treatment with EGFR tyrosine kinase inhibitors (EGFR‐TKI). The mechanisms of resistance to EGFR‐TKI are multifactorial, and the detection of these mechanisms is critical for treatment choices in patients who have progressed after EGFR‐TKI therapy. We evaluated the feasibility of a molecular barcode method using next‐generation sequencing to detect multifactorial resistance mechanisms in circulating tumor DNA and compared the results with those obtained using other technologies. Plasma samples were collected from 25 EGFR mutation‐positive NSCLC patients after the development of EGFR‐TKI resistance. Somatic mutation profiles of these samples were assessed using two methods of next‐generation sequencing and droplet digital PCR (ddPCR). The positive rate for EGFR‐sensitizing mutations was 18/25 (72.0%) using ddPCR, 17/25 (68.0%) using amplicon sequencing, and 19/25 (76.0%) using molecular barcode sequencing. Rate of the EGFR T790M resistance mutation among patients with EGFR‐sensitizing mutations was shown to be 7/18 (38.9%) using ddPCR, 6/17 (35.3%) using amplicon sequencing, and 8/19 (42.1%) using molecular barcode sequencing. Copy number gain in the MET gene was detected in three cases using ddPCR. PIK3CA,KRAS and TP53 mutations were detected using amplicon sequencing. Molecular barcode sequencing detected PIK3CA,TP53,KRAS, and MAP2K1 mutations. Results of the three assays were comparable; however, in cell‐free DNA, molecular barcode sequencing detected mutations causing multifactorial resistance more sensitively than did the other assays.

Clinical Pharmacokinetics and Pharmacodynamics of the Epidermal Growth Factor Receptor Inhibitor Panitumumab in the Treatment of Colorectal Cancer

Despite progress in the treatment of metastatic colorectal cancer (mCRC) in the last 15 years, it is still a condition with a relatively low 5-year survival rate. Panitumumab, a fully human monoclonal antibody directed against the epidermal growth factor receptor (EGFR), is able to prolong survival in patients with mCRC. Panitumumab is used in different lines of therapy in combination with chemotherapy, and as monotherapy for the treatment of wild-type (WT) RAS mCRC. It is administered as an intravenous infusion of 6 mg/kg every 2 weeks and has a t_½ of approximately 7.5 days. Elimination takes place via two different mechanisms, and immunogenicity rates are low. Only RAS mutations have been confirmed as a negative predictor of efficacy with anti-EGFR antibodies. Panitumumab is generally well tolerated and has a manageable toxicity profile, despite a very high prevalence of dermatologic side effects. This article presents an overview of the clinical pharmacokinetics and pharmacodynamics of panitumumab, including a description of the studies that led to its approval in the different lines of therapy of mCRC.

Pan-Asian adapted ESMO consensus guidelines for the management of patients with metastatic colorectal cancer: a JSMO-ESMO initiative endorsed by CSCO, KACO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) consensus guidelines for the treatment of patients with metastatic colorectal cancer (mCRC) was published in 2016, identifying both a more strategic approach to the administration of the available systemic therapy choices, and a greater emphasis on the use of ablative techniques, including surgery. At the 2016 ESMO Asia Meeting, in December 2016, it was decided by both ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting, endorsed by both ESMO and JSMO, immediately after the JSMO 2017 Annual Meeting. The aim was to adapt the ESMO consensus guidelines to take into account the ethnic differences relating to the toxicity as well as other aspects of certain systemic treatments in patients of Asian ethnicity. These guidelines represent the consensus opinions reached by experts in the treatment of patients with mCRC identified by the Presidents of the oncological societies of Japan (JSMO), China (Chinese Society of Clinical Oncology), Korea (Korean Association for Clinical Oncology), Malaysia (Malaysian Oncological Society), Singapore (Singapore Society of Oncology) and Taiwan (Taiwan Oncology Society). The voting was based on scientific evidence and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

Optimizing sequential treatment with anti-EGFR and VEGF mAb in metastatic colorectal cancer: current results and controversies

Anti-EGFR mAb (cetuximab or panitumumab) and anti-VEGF mAb (bevacizumab) are the two main targeted agents available for RAS wild-type (WT) metastatic colorectal cancer (mCRC) treatment. Nonetheless, three head-to-head clinical trials evaluating anti-EGFR mAb vs -VEGF mAb in first-line treatment failed to conclude a uniform result. Recently, a few small clinical studies revealed that prior use of bevacizumab may impair the effect of cetuximab or panitumumab. Preclinical studies have also suggested that pretreatment with bevacizumab may lead to simultaneous resistance to anti-EGFR mAb. Therefore, we performed this review to summarize the available data regarding the optimal sequential treatment of anti-EGFR and -VEGF mAb for RAS or KRAS WT mCRC and discuss the potential mechanisms that may explain this phenomenon. Primary tumor location and early tumor shrinkage have emerged as new potential prognostic and predictive factors in mCRC. We also collected information to explore whether these factors affect the optimal sequencing of targeted therapy in mCRC. However, definite conclusions cannot be made, and we can only speculate on optimal treatment recommendations based on the contradictory results.

Repeat hepatectomy with systemic chemotherapy might improve survival of recurrent liver metastasis from colorectal cancer-a retrospective observational study

BACKGROUND

Although hepatectomy for metastatic colorectal cancer (mCRC) prolongs survival in up to 40% of people, recurrence rates approach 70%. We used a multidisciplinary approach to treat recurrent liver metastases, including chemotherapy, surgery, and palliative care. On the other hand, development of chemotherapeutic agents is remarkable and improves long-term survival. However, whether chemotherapy and repeat hepatectomy combination therapy improve survival or not is still unclear. The aim of this study was to analyze the outcomes of repeat hepatectomy with systemic chemotherapy for mCRC.

METHODS

Following Institutional Review Board approval, we reviewed the records of all patients who underwent hepatectomy for mCRC between 1974 and 2015 at Fujita Health University Hospital. We used the Kaplan-Meier method to estimate overall survival from the first and last hepatectomy in multi hepatectomy cases after 2005 and compared outcomes between groups using the log-rank test.

RESULTS

A total of 426 liver resections were performed for mCRC; of these, 236 cases were performed after 2005 (late group). In 118 (50%) cases, the site of recurrence was the liver, 59 (50%) underwent repeat hepatectomy, and 14 cases had ≥ 2 repeat hepatectomies. Overall survival (OS) before and after 2005 was 42.2 and 64.1 months, respectively, with the late group having better OS compared to the early (1974-2004) group. OS for single hepatectomy cases was 83.2 months, for two hepatectomies was 42.9 months, and for three hepatectomies was 35.3 months. In total, 59 patients did not undergo surgery after recurrence with an OS of 28.7 months. Mortality of the second and third repeat hepatectomy was 1.7% and 15.3%, respectively.

CONCLUSION

Repeat hepatectomy with systemic chemotherapy for mCRC is feasible and might achieve improved survival in carefully selected patients.

REVERCE: a randomized phase II study of regorafenib followed by cetuximab versus the reverse sequence for previously treated metastatic colorectal cancer patients

BACKGROUND

The objective of this randomized phase II trial was to evaluate efficacy and safety of the therapeutic sequence of regorafenib followed by cetuximab, compared with cetuximab followed by regorafenib, as the current standard sequence for metastatic colorectal cancer patients.

PATIENTS AND METHODS

Patients with KRAS exon 2 wild-type metastatic colorectal cancer after failure of fluoropyrimidine, oxaliplatin, and irinotecan were randomized to receive sequential treatment with regorafenib followed by cetuximab ± irinotecan (R-C arm), or the reverse sequence [cetuximab ± irinotecan followed by regorafenib (C-R arm)]. The primary end point was overall survival (OS). Key secondary end points included progression-free survival (PFS) with initial treatment (PFS1), PFS with second treatment (PFS2), safety, and quality of life. Exploratory end points included serial biomarker analyses, including oncogenic alterations from circulating tumor DNA or multiple serum or plasma proteins.

RESULTS

One-hundred one patients were randomized and eligible for efficacy analysis. Sequential treatment was successful in 86% patients in both arms. Median OS for R-C and C-R was 17.4 and 11.6 months, respectively (P = 0.0293), with a hazard ratio (HR) of 0.61 for OS [95% confidence interval (CI) 0.39-0.96]. The HR for PFS1 (regorafenib in R-C versus cetuximab in C-R) was 0.97 (95% CI 0.61-1.54), and PFS2 (C in R-C versus R in C-R) was 0.29 (95% CI 0.17-0.50). No unexpected safety signals were observed. The quality of life scores during the entire treatment period was not significantly different between the two arms. Circulating biomarker analyses showed emerging oncogenic alterations in RAS, BRAF, EGFR, HER2, and MET, which were more commonly detected after cetuximab than after regorafenib.

CONCLUSIONS

The therapeutic sequence of regorafenib followed by cetuximab suggests a longer OS than the current standard sequence.

Update review of skin adverse events during treatment of lung cancer and colorectal carcinoma with epidermal growth receptor factor inhibitors

The past decades have witnessed a rapid increase in the use of molecularly targeted therapies. One class of agents includes the epidermal growth factor receptor inhibitors (EGFRIs), which afford patients longer progression-free survival (PFS) times, especially among non-small cell lung cancer (NSCLC) and metastatic colorectal carcinoma (mCRC). Certain adverse effects, particularly skin toxicity, are mainly manifested as rash, xerosis, pruritus, nails changes, hair changes and mucositis. Previous studies reported the adverse events occurred based on the cutaneous inflammation reaction. Treatment recommended glucocorticoids and antibiotics. It is suggested that skin toxicity is an important issue because it usually affects patients' quality of life (QoL) and still causes dose reduction or discontinuation of targeted therapies. For these reasons, more and more oncologists and dermatologists recognize the importance of recognition and management of skin toxicities with the expansion in availability of EGFRIs. In this review, we conducted a systematic review of recent data to examine the types and frequencies of dermatologic toxicities associated with anti-epidermal growth factor receptor (EGFR) therapies in NSCLC and mCRC. In addition, we would like to explore the management and treatment options currently used by clinicians based on the possible mechanism.

Targeted Therapy for Colorectal Cancers With Non-V600 BRAF Mutations: Perspectives for Precision Oncology

BRAF mutations are found in up to 10% of colorectal cancers (CRC). Whereas the majority of BRAF mutant CRCs harbor V600 mutations, up to 25% express non-V600 BRAF mutations. It has been established that BRAF V600E mutations in CRC predict unresponsiveness to epidermal growth factor receptor (EGFR) inhibition—cetuximab and/or panitumumab—as a result of the constitutive activation of the mitogen-activated protein kinase pathway downstream of EGFR signaling. As more centers begin using next-generation sequencing assays to detect BRAF mutations, oncologists are more frequently confronted with treating patients with non-V600 BRAF mutations. In many instances, clinicians may be hesitant to use EGFR inhibitors for these patients, as it is largely assumed that tumors with non-V600 BRAF mutations activate the mitogen-activated protein kinase pathway in a similar manner to RAS or BRAF V600E mutations and would therefore be equally refractory to EGFR inhibition; however, the evidence that currently exists to substantiate this claim is mixed and incomplete. Recent data demonstrate that non-V600 BRAF mutant CRC is a distinct clinical entity with a favorable prognosis compared with CRC with V600E mutations. Preclinical data and several case reports suggest that a subset of BRAF non-V600 mutations that impair the protein's kinase activity may in fact confer heightened sensitivity to EGFR inhibition because of dependency on upstream receptor tyrosine kinase signaling. This review summarizes the clinical characteristics and targeted therapy approaches for non-V600 BRAF mutant CRCs, speculates on the value of non-V600 BRAF mutations as predictive biomarkers of responsiveness to EGFR inhibitors, and highlights outstanding questions in this emerging area of precision oncology.

A comprehensive gene mutation analysis of liquid biopsy samples from patients with metastatic colorectal cancer to the ovary: A case report

Liquid biopsies of circulating tumor DNA (ctDNA) can detect molecular alterations, including tumor-specific mutations, and have recently been used as a non-invasive diagnostic, prognostic, and predictive tool. However, this technique is not commonly used in the gynecological field. Gene mutation profiling of liquid biopsy samples was performed using CAncer Personalized Profiling by deep Sequencing (CAPP-Seq), a novel next-generation sequencing-based approach to ultrasensitive ctDNA detection, in order to make it possible to molecularly diagnose metastatic colorectal cancer to the ovary. Liquid biopsy (plasma) samples and formalin-fixed paraffin-embedded tumor samples were obtained from two patients with ovarian tumors, who had a history of surgery for colorectal cancer, and comprehensive gene mutation profiling was conducted using CAPP-Seq. In patient 1, mutations were identified in the same three regions in both the ovarian tumor and preoperative plasma sample (in the KRAS G13D, APC E1306*, and TP53 H193Y genes). In patient 2, mutation was identified in the same one region in all the primary colorectal tumor, the ovarian tumor, and preoperative plasma sample (in APC R216* gene). These mutations are well-known genetic signatures of colorectal cancer, suggesting that the ovarian tumor was metastatic. Tthe gene mutation patterns of colorectal cancer were examined by subjecting liquid biopsy samples from patients with suspected metastatic ovarian tumors to CAPP-Seq. Gene mutation profiling of liquid biopsy samples can contribute to the preoperative differential diagnosis of metastatic ovarian cancer and its subsequent personalized treatment.

Drug resistance and new therapies in colorectal cancer

Colorectal cancer (CRC) is often diagnosed at an advanced stage when tumor cell dissemination has taken place. Chemo- and targeted therapies provide only a limited increase of overall survival for these patients. The major reason for clinical outcome finds its origin in therapy resistance. Escape mechanisms to both chemo- and targeted therapy remain the main culprits. Here, we evaluate major resistant mechanisms and elaborate on potential new therapies. Amongst promising therapies is α-amanitin antibody-drug conjugate targeting hemizygous p53 loss. It becomes clear that a dynamic interaction with the tumor microenvironment exists and that this dictates therapeutic outcome. In addition, CRC displays a limited response to checkpoint inhibitors, as only a minority of patients with microsatellite instable high tumors is susceptible. In this review, we highlight new developments with clinical potentials to augment responses to checkpoint inhibitors.

Efficacy of bevacizumab versus epidermal growth factor receptor inhibitors for wild-type RAS metastatic colorectal cancer: a meta-analysis

Background

Results from several prospective clinical trials comparing anti-epidermal growth factor receptor (EGFR) therapy and anti-vascular endothelial growth factor (VEGF) therapy plus chemotherapy for wild-type RAS metastatic colorectal cancer (mCRC) have been inconsistent. This meta-analysis aims to investigate the optimal choice for these target agents.

Methods

We searched for clinical trials in both electronic databases from inception until January 2018 and recent conference abstracts to identify prospective clinical studies comparing the efficacy of a VEGF inhibitor (bevacizumab) versus EGFR inhibitors (cetuximab or panitumumab) on wild-type RAS (including its subset KRAS) mCRC. All analyses were conducted using RevMan 5.3 software.

Results

A total of 5 studies were included. EGFR inhibitors were associated with a significant benefit in terms of overall survival (OS) compared with VEGF inhibitors in wild-type KRAS or wild-type RAS populations, with hazard ratios (HRs) equal to 0.86 (95% CI: 0.78, 0.95; p=0.003) and 0.83 (95% CI: 0.72, 0.95; p=0.007), respectively. This survival benefit was limited to the first-line setting. No difference was found for progression-free survival (PFS), whereas the objective response rate (ORR) was significantly increased in the wild-type RAS population (OR: 0.64; 95% CI: 0.50, 0.82; p=0.0004). No difference in OS was noted between EGFR inhibitors versus a VEGF inhibitor plus the FOLFIRI regimen, whereas superior survival was noted for EGFR inhibitors plus the mFOLFOX6 regimen versus a VEGF inhibitor (HR: 0.75; 95% CI: 0.57, 0.98; p=0.04). PFS was significantly prolonged (HR: 1.48; 95% CI: 1.14, 1.92; p=0.003), whereas a trend favoring OS (HR: 1.23; 95% CI: 0.93, 1.63; p=0.14) was noted for a VEGF inhibitor in patients with right-sided tumors, with no difference in the ORR (OR: 0.85; 95% CI: 0.52, 1.38; p=0.51). However, left-sided tumors exhibited superior OS (HR: 0.71; 95% CI: 0.59, 0.85; p=0.0002), PFS (HR: 0.84; 95% CI: 0.72, 0.98; p=0.03), and ORR (OR: 0.66; 95% CI: 0.48, 0.92; p=0.01) for EGFR inhibitors.

Conclusion

This meta-analysis suggests the superiority of anti-EGFR therapy compared with anti-VEGF therapy for mCRC with wild-type RAS. Primary tumor location should be taken into account in target drug selection. Further research is still needed to confirm which inhibitor may be a better choice when combined with different chemotherapy regimens.

Skin toxicity with anti-EGFR monoclonal antibody in cancer patients: a meta-analysis of 65 randomized controlled trials

We performed a meta-analysis to fully investigate the skin toxicities of anti-EGFR monoclonal antibody (EGFR-MoAbs) in cancer patients. The relevant studies of the randomized controlled trials (RCTs) in cancer patients treated with EGFR-MoAbs were retrieved and the systematic evaluation was conducted. EMBASE, MEDLINE, and PubMed were searched for articles published till November 2017. The relevant RCTs in cancer patients treated with EGFR-MoAbs were retrieved and the systematic evaluation was conducted. 65 RCTs and 25994 patients were included. The current meta-analysis suggests that the use of EGFR-MoAbs significantly increases the risk of developing all-grade and high-grade skin toxicity, such as rash, hand-foot syndrome, dry skin and oral mucositis. Rash was the most common skin toxicity. Patients receiving nimotuzumab were associated with the least risk of skin toxicity. The risk of high-grade skin toxicity tended to be higher in the study in which the EGFR-MoAbs treatment duration was longer. The available data suggested that the use of EGFR-MoAbs significantly increases the risk of developing skin toxicity. Physicians should be aware of skin toxicity and should monitor cancer patients when receiving EGFR-MoAbs.

Previous Bevacizumab and Efficacy of Later Anti-Epidermal Growth Factor Receptor Antibodies in Metastatic Colorectal Cancer: Results From a Large International Registry

BACKGROUND

The FIRE-3 [5-fluorouracil, folinic acid, and irinotecan (FOLFIRI) plus cetuximab versus FOLFIRI plus bevacizumab in first line treatment colorectal cancer (CRC)] study reported that first-line FOLFIRI plus cetuximab versus FOLFIRI plus bevacizumab resulted in similar progression-free survival (PFS) but improved overall survival (OS). A potential explanation is that the initial biologic agent administered in metastatic CRC (mCRC) affects later line efficacy of the other treatments. We sought to test this hypothesis.

MATERIALS AND METHODS

We interrogated our mCRC registry (Treatment of Recurrent and Advanced Colorectal Cancer) regarding treatment and outcome data for RAS wild-type patients receiving epidermal growth factor receptor inhibitors (EGFRIs) in second and subsequent lines. Survival outcomes from the beginning of EGFRI use were determined as a function of previous bevacizumab use and the interval between ceasing bevacizumab and beginning EGFRI use.

RESULTS

Of 2061 patients, 222 eligible patients were identified, of whom 170 (77%) had received previous bevacizumab and 52 (23%) had not. PFS and OS from the start of EGFRIs did not differ by previous bevacizumab use (3.8 vs. 4.2 months; hazard ratio [HR], 1.12; P = .81; 9.0 vs. 9.2 months; HR, 1.19; P = .48, respectively) for the whole cohort or when analyzed by the primary tumor side (HR for left side, 1.07; P = .57; HR for right side, 1.2; P = .52). PFS was significantly shorter with right-sided primary tumors when the interval between bevacizumab and EGFRI use was < 6 versus > 6 months (median, 2.2 vs. 6 months; HR, 2.23; P = .01) but not with left-sided tumors (median, 4.2 vs. 5.5 months; HR, 1.12; P = .26).

CONCLUSION

Previous bevacizumab use had no effect on the activity of subsequent EGFRIs. The apparent effect of time between biologic agents in right-sided tumors might reflect patient selection.

Monitoring circulating tumor DNA revealed dynamic changes in KRAS status in patients with metastatic colorectal cancer

KRAS mutated circulating tumor DNA (MctDNA) can be monitored in the blood of patients with metastatic colorectal cancer (mCRC), but dynamic changes have not been determined. Four hundred and fifty-seven plasma samples were collected prospectively from 85 mCRC patients who underwent chemotherapy. MctDNA in plasma was detected by droplet digital PCR, and the percentage of MctDNA in total circulating cell-free DNA was calculated. KRAS assessment in tumor tissues showed 29 patients with the mutant-type (MT) and 56 patients with the wild-type (WT). Twenty-three of 29 MT patients (79.3%) and 28 of 56 WT patients (50.0%) showed MctDNA. Emergence of MctDNA was recognized during treatments with various drugs. Regardless of KRAS status in tumor tissues, patients with MctDNA in blood showed poor progression-free survival with first-line treatment. Median percentage of MctDNA accounted for 10.10% in MT patients and 0.22% in WT patients. These differences between MT and WT likely affected patterns of changes in MctDNA. KRAS monitoring identified dynamic changes in MctDNA, such as continuous, intermittent, and transient changes (quick elevation and disappearance). Emergence of MctDNA involved drug resistance, except for transient changes, which were seen in WT patients and likely corresponded with the drug response. Transient changes could be involved in recovery of sensitivity to anti-EGFR antibody in WT patients. Monitoring MctDNA during various treatments showed dynamic changes in KRAS status and could provide useful information for determining treatments for patients with mCRC.

Optimising the use of cetuximab in the continuum of care for patients with metastatic colorectal cancer

The anti-epidermal growth factor receptor (EGFR) monoclonal antibody cetuximab in combination with chemotherapy is a standard of care in the first-line treatment of RAS wild-type (wt) metastatic colorectal cancer (mCRC) and has demonstrated efficacy in later lines. Progressive disease (PD) occurs when tumours develop resistance to a therapy, although controversy remains about whether PD on a combination of chemotherapy and targeted agents implies resistance to both components. Here, we propose that some patients may gain additional clinical benefit from the reuse of cetuximab after having PD on regimens including cetuximab in an earlier treatment line. We conducted a non-systematic literature search in PubMed and reviewed published and ongoing clinical trials, focusing on later-line cetuximab reuse in patients with mCRC. Evidence from multiple studies suggests that cetuximab can be an efficacious and tolerable treatment when continued or when fit patients with mCRC are retreated with it after a break from anti-EGFR therapy. Furthermore, on the basis of available preclinical and clinical evidence, we propose that longitudinal monitoring of RAS status may identify patients suitable for such a strategy. Patients who experience progression on cetuximab plus chemotherapy but have maintained RAS wt tumour status may benefit from continuation of cetuximab with a chemotherapy backbone switch because they have probably developed resistance to the chemotherapeutic agents rather than the biologic component of the regimen. Conversely, patients whose disease progresses on cetuximab-based therapy due to drug-selected clonal expansion of RAS-mutant tumour cells may regain sensitivity to cetuximab following a defined break from anti-EGFR therapy. Looking to the future, we propose that RAS status determination at disease progression by liquid, needle or excisional biopsy may identify patients eligible for cetuximab continuation and rechallenge. With this approach, treatment benefit can be extended, adding to established continuum-of-care strategies in patients with mCRC.

FOLFIRI plus panitumumab in the treatment of wild-type KRAS and wild-type NRAS metastatic colorectal cancer

Background

The aim of this study was to investigate the efficacy and safety of first-line panitumumab plus folinic acid, 5-fluorouracil and irinotecan (FOLFIRI) in patients with wild-type KRAS and wild-type NRAS metastatic colorectal cancer (mCRC).

Methods

Patients with wild-type KRAS and wild-type NRAS mCRC presenting to the medical oncology department of the Okmeydani Training and Research Hospital in Istanbul, Turkey, between April 2014 and January 2018 were enrolled in this study.

Results

A total of 64 patients (35 males and 29 females) with a median age of 59 (35–81) years old were enrolled. The median follow-up was 18.9 months, and the median progression-free survival was 13 months. The median overall survival (OS) was 26 months in the patients with wild-type KRAS and wild-type NRAS mCRC. It was 90.4% for the 6-month OS, 79.5% for the 1-year OS, 53.7% for the 2-year OS and 31.1% for the 3-year OS. The median OS of the patients who underwent metastasectomies was 40 [95% confidence interval (CI) = 19.9–60.1] months, and the median OS of the patients without metastasectomies was 22 (95% CI = 17.7–26.4) months. There was a statistically significant difference between these (P = 0.007).

Conclusion

The first-line FOLFIRI plus panitumumab was associated with favourable efficacy in the patients with wild-type KRAS and wild-type NRAS mCRC, and it was well tolerated. The removal of the metastases that became resectable after chemotherapy further prolonged the patients’ survival.

Trial registration

Retrospectively registered: 33886

Chemotherapy plus Panitumumab Versus Chemotherapy plus Bevacizumab in Metastatic Colorectal Cancer: A Meta-analysis

Panitumumab and bevacizumab have been widely used in combination with chemotherapy for patients with wild type RAS metastatic colorectal cancer (mCRC). Whether panitumumab or bevacizumab was the optimal option remained controversial. Thus, we conducted a meta-anaylsis to evaluate chemotherapy plus panitumumab (C + P) versus chemotherapy plus bevacizumab (C + B) in wild type RAS mCRC. Electronic databases including PubMed, Embase, and Web of Science, Cochrane Library, ClinicalTrials.gov, were searched. This meta-analysis estimated the progression-free survival (PFS), overall survival (OS), overall response rate (ORR) and adverse events (AEs). Three randomized controlled trials with a total number of 577 patients were included. In wild type RAS population, PFS [hazard ratio (HR) = 0.96; 95% confidence interval (CI), 0.76 to 1.15] and OS (HR = 0.90; 95% CI, 0.54 to 1.27) and ORR [relative ratio (RR) = 2.06; 95% CI, 0.86 to 4.90] appeared similar between the two treatments, the incidence of AEs slightly increased (RR = 1.16; 95% CI 1.08 to 1.26). In conclusion, there was insufficient evidence to precisely conclude that combination treatment of C + P had an improved efficacy compared with C + B. Further large-scale and better-designed clinical trials are still needed to evaluate the combination treatment of C + P in patients with wild type RAS mCRC.