A randomized phase III trial on maintenance treatment with bevacizumab alone or in combination with erlotinib after chemotherapy and bevacizumab in metastatic colorectal cancer: the Nordic ACT Trial

MODUL cohort 2: an adaptable, randomized, signal-seeking trial of fluoropyrimidine plus bevacizumab with or without atezolizumab maintenance therapy for BRAFwt metastatic colorectal cancer

Background

MODUL is an adaptable, signal-seeking trial designed to test novel agents in predefined patient subgroups in first-line metastatic colorectal cancer (mCRC).

Patients and methods

Patients with measurable, unresectable, previously untreated mCRC received induction with ≤8 cycles of FOLFOX + bevacizumab followed by randomization to maintenance treatment comprising control [fluoropyrimidine (FP)/bevacizumab: 5-fluorouracil 1600-2400 mg/m² 46-h intravenous (i.v.) infusion day 1 q2 weeks plus leucovorin 400 mg/m² 2-h infusion i.v. day 1 q2 weeks or capecitabine 1000 mg/m² b.i.d. orally days 1-14 every 21 days; bevacizumab 5 mg/kg 15-30-min i.v. infusion q2 weeks] or experimental treatment in one of four biomarker-driven cohorts. In patients with BRAF wild-type (BRAF^wt) tumors (cohort 2), experimental treatment was FP/bevacizumab + atezolizumab (800 mg 60-min i.v. infusion q2 weeks). Primary efficacy endpoint was progression-free survival (PFS; intent-to-treat population). Enrollment is complete; efficacy and safety findings from cohort 2 are presented.

Results

Four hundred and forty-five patients with BRAF^wt mCRC were randomized (2 : 1) to maintenance in cohort 2. At a median follow-up of 10.5 months, PFS outcome hypothesis was not met [hazard ratio (HR) 0.92; 95% confidence interval (CI) 0.72-1.17; P = 0.48]; overall survival (OS) was immature. At a median follow-up of 20.3 months (2-year survival follow-up), PFS benefit was also not met (HR 0.95; 95% CI 0.77-1.18; P = 0.666); OS HR with nearly two-thirds of patients with events was 0.83 (95% CI 0.65-1.05; P = 0.117). No new safety signals were identified. The most common grade ≥3 treatment-emergent adverse events (TEAEs) for experimental versus control arms were hypertension (6.1% versus 4.2%), diarrhea (3.1% versus 2.1%), and palmar-plantar erythrodysesthesia syndrome (1.0% versus 2.5%). Four patients experienced TEAEs with fatal outcome, two were study treatment-related: hepatic failure (experimental arm) and large intestine perforation (control arm; bevacizumab-related).

Conclusions

Adding atezolizumab to FP/bevacizumab as first-line maintenance treatment after FOLFOX + bevacizumab induction for BRAF^wt mCRC did not improve efficacy outcomes.

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MODUL is an adaptable, signal-seeking trial of novel combinations in predefined subgroups of patients with mCRC.

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In cohort 2 (BRAF^wt mCRC), adding atezolizumab to FP/bevacizumab (bev) first-line maintenance therapy did not improve PFS or OS versus FP/bev.

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ORR and DCR were numerically but not statistically significantly higher with atezolizumab + FP/bev versus FP/bev.

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The safety profile of atezolizumab + FP/bev was consistent with previous findings with no new safety signals identified.

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Findings from MODUL cohort 2 indicate that immunotherapy has limited efficacy in patients with microsatellite stable mCRC.

Spatial Immunology in Liver Metastases from Colorectal Carcinoma according to the Histologic Growth Pattern

Simple Summary

In the era of immunotherapy, the tumor microenvironment (TME) has attracted special interest. However, colorectal liver metastases (CRC-LM) present histological peculiarities that could affect the interaction of immune and tumor cells such as fibrotic encapsulation and dense intratumoral stroma. We explored the spatial distribution of lymphocytic infiltrates in CRC-LM in the context of the histologic growth patterns using multispectral digital pathology providing data on three different scenarios, tumor periphery, invasive margin, and central tumoral areas. Our results illustrate a similar poor cell density of CD8⁺ cells between different metastases subtypes in intratumoral regions. However, in encapsulated metastases, cytotoxic cells reach the tumor cells while remaining retained in stromal areas in non-encapsulating metastases. Some aspects are still unresolved, such as understanding the reason why most lymphocytes are largely retained in the capsule.

Abstract

Colorectal cancer liver metastases (CRC-LM) present differential histologic growth patterns (HGP) that determine the interaction between immune and tumor cells. We explored the spatial distribution of lymphocytic infiltrates in CRC-LM in the context of the HGP using multispectral digital pathology. We did not find statistically significant differences of immune cell densities in the central regions of desmoplastic (_dHGP) and non-desmoplastic (_ndHGP) metastases. The spatial evaluation reported that _dHGP-metastases displayed higher infiltration by CD8⁺ and CD20⁺ cells in peripheral regions as well as CD4⁺ and CD45RO⁺ cells in _ndHGP-metastases. However, the reactive stroma regions at the invasive margin (IM) of _ndHGP-metastases displayed higher density of CD4⁺, CD20⁺, and CD45RO⁺ cells. The antitumor status of the TIL infiltrates measured as CD8/CD4 reported higher values in the IM of encapsulated metastases up to 400 μm towards the tumor center (p < 0.05). Remarkably, the IM of _dHGP-metastases was characterized by higher infiltration of CD8⁺ cells in the epithelial compartment parameter assessed with the ratio CD8^epithelial/CD8^stromal, suggesting anti-tumoral activity in the encapsulating lesions. Taking together, the amount of CD8⁺ cells is comparable in the IM of both HGP metastases types. However, in _dHGP-metastases some cytotoxic cells reach the tumor nests while remaining retained in the stromal areas in _ndHGP-metastases.

Quality of life assessment and reporting in colorectal cancer: A systematic review of phase III trials published between 2012 and 2018

BACKGROUND

In this study, our aim was to describe quality of life (QoL) prevalence and heterogeneity in QoL reporting in colorectal cancer phase III trials.

METHODS

We included all phase III trials evaluating anticancer drugs in colorectal cancer patients published between 2012 and 2018 by 11 major journals.

RESULTS

Out of the 67 publications identified, in 41 (61.2 %) QoL was not listed among endpoints. Out of 26 primary publications of trials including QoL among endpoints, QoL results were not reported in 10 (38.5 %). Overall, no QoL data were available in 51/67 (76.1 %) primary publications. In particular, in the metastatic setting, QoL data were not available in 12/18 (66.7 %) trials with primary endpoint overall survival, and in 20/29 (69.0 %) trials with other primary endpoints.

CONCLUSIONS

QoL was absent in a high proportion of recently published phase III trials in colorectal cancer, even in trials of second or further lines, where attention to QoL should be particularly high.

Maintenance treatment in metastatic colorectal cancer: in search of the best strategy

Over the last 2 decades, the standard fluoropyrimidine-based chemotherapy backbone for metastatic colorectal cancer has been complemented by the addition of novel biological agents, achieving impressive increases in 5-year survival rates. Nonetheless, these new combinations have also entailed increases in toxicity, leading to evaluation of de-escalated chemotherapy regimens and "drug holiday" periods in attempts to reduce side effects and optimise quality of life without impairing efficacy. Here, we review the current and emerging evidence for maintenance schedules with chemotherapy and targeted agents, versus continuous treatment after induction treatment, in metastatic colorectal cancer patients.

Efficacy and safety of bevacizumab-based maintenance therapy in metastatic colorectal cancer: A meta-analysis

OBJECTIVE

To identify the optimal treatment strategy after first-line induction chemotherapy for metastatic colorectal cancer (mCRC).

METHODS

We conducted a meta-analysis of randomized controlled trials comparing bevacizumab-based maintenance therapy, observation, and continuous chemotherapy.We searched the PubMed, Embase, and Cochrane databases for relevant articles published through March 2018. All randomized phase-III trials evaluating bevacizumab-based maintenance treatment after bevacizumab-based induction treatment were eligible for inclusion. The primary and secondary endpoints were progression-free survival (PFS) and overall survival (OS), respectively. Hazard ratios (HRs) with 95% confidence intervals (CIs) or data for calculating HRs with 95% CIs were extracted. The RevMan v5.3 (Copenhagen, Denmark) software was used for data analysis.

RESULTS

Nine trials (3121 patients) were included in this meta-analysis. Compared with observation alone, bevacizumab-based maintenance therapy significantly improved PFS (HR: 0.62, 95% CI: 0.47-0.82) and showed a trend toward prolonged OS (HR: 0.93, 95% CI: 0.83-1.05). The incidence of grade 3/4 toxicity, including hypertension and fatigue, was higher after maintenance therapy than after observation alone. PFS (HR: 0.91, 95% CI: 0.70-1.18) and OS (HR: 0.88, 95% CI: 0.74-1.04) did not differ between the maintenance treatment and continuous chemotherapy groups. Grade 3/4 toxicity, including diarrhea and sensory neuropathy, was less common after maintenance therapy than after continuous chemotherapy.

CONCLUSION

Bevacizumab-based maintenance therapy significantly improved PFS, showed a trend toward prolonged OS, and reduced cumulative grade 3/4 toxicity relative to continuous chemotherapy with comparable efficacy. Although maintenance therapy was beneficial, the optimal strategy should be individualized.

Combination strategies based on epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors for cancer patients: Pooled analysis and subgroup analysis of efficacy and safety

BACKGROUND

Combination therapy based on epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is an emerging trend in cancer treatment, but the clinical value of EGFR-TKIs combination therapy remains controversial. Thus, we conducted a comprehensive analysis of randomized controlled trials (RCTs) comparing EGFR-TKIs combination therapies with monotherapies, aiming to evaluate the safety and efficacy of EGFR-TKIs based combination therapy and to find a more beneficial combination strategy.

METHODS

We searched for clinical studies that evaluated EGFR-TKIs combination therapy in cancer. We extracted data from these studies to evaluate the relative risk (RR) of overall response rate (ORR) and grade 3/4 treatment-related adverse events (AEs), the hazard ratios (HRs) of overall survival (OS), and progression-free survival (PFS).

RESULTS

Fourteen RCTs were identified (n = 3774). Treatments included combinations of EGFR-TKIs and chemotherapy, combinations of EGFR-TKIs and radiotherapy, and combinations of EGFR-TKIs and bevacizumab. EGFR-TKIs combination therapies showed higher ORR [RR: 1.62; 95% confidence interval (95% CI):1.16-2.26; P = .005], PFS (HR: 0.76; 95% CI: 0.64-0.89; P = .001), and OS (HR: 0.88; 95% CI: 0.79-0.97; P = .013) values than monotherapies. However, higher grade 3/4 treatment-related AEs (RR: 1.79; 95% CI: 1.02-3.15; P = .000) were observed in combination therapy than in monotherapy.

CONCLUSION

Our pooled analysis and subgroup analysis results showed that the addition of chemotherapy to EGFR-TKIs better benefits PFS and safety. Adding bevacizumab was associated with better ORR and OS. The efficacy and safety of a bevacizumab-EGFR-TKIs-chemotherapy combination should be investigated further.

Comparative and combined effectiveness of innovative therapies in cancer: a literature review

To achieve therapeutic innovation in oncology, already expensive novel medicines are often concomitantly combined to potentially enhance effectiveness. While this aggravates the pricing problem, comparing effectiveness of novel yet expensive (concomitant) treatments is much needed for healthcare decision-making to deliver effective but affordable treatments. This study reviewed published clinical trials and real-world studies of targeted and immune therapies. In total, 48 studies compared and/or combined multiple novel products on breast, colorectal, lung and melanoma cancers. To a great extent, products evaluated in each study were owned by one manufacturer. However, cross-manufacturer assessments are also needed. Next to costs and intensive market competition, the absence of a regulatory framework enforcing real-world multiproduct studies prevents these from being conducted. Trusted third parties could facilitate such real-world studies, for which appropriate and efficient data access is needed.

Bevacizumab and erlotinib versus bevacizumab for colorectal cancer treatment: systematic review and meta-analysis

Background Improving the survival of patients diagnosed with metastatic colorectal cancer requires the use of chemotherapy to be managed with minimum adverse effects. Randomized control trials (RCTs) have shown promising results with a combination of bevacizumab and erlotinib to block two important tumor growth pathways, namely vascular endothelial growth factor and epidermal growth factor receptor. Aim of the Review We aimed to examine the efficacy and safety of the combination of bevacizumab and erlotinib with bevacizumab alone in the maintenance treatment of metastatic colorectal cancer, by examining PFS, OS, overall response rate (ORR), and toxicity. This study performed a systematic review meta-analysis using existing randomized clinical trial. Methods Randomized controlled trials were systematically reviewed from PubMed, Cochrane library, SCOPUS, CRD, and Google scholar databases. After evaluating the quality of studies through the Cochrane checklist, data of the relevant studies were extracted. This meta-analysis included outcomes of overall survival, progression-free survival of the disease through the hazard ratio, and the upper and lower confidence intervals for the third and fourth degree side effects of relative risk. To perform the meta-analysis for both types of survival, two fixed and random effect models were used. Results A total of three trials, providing data of 682 patients who received maintenance treatment, were included in this meta-analysis. Conclusion The combination of bevacizumab and erlotinib significantly increased the overall survival compared to using bevacizumab alone [HR = 0.78, 95% CI 0.66-0.93]. This combination, effectively increased progression-free survival [HR = 0.81, 95% CI 0.7-0.93] too. The side effects of diarrhea and grade III rash were more frequent in the group administered bevacizumab plus erlotinib. The combination of bevacizumab and erlotinib, in the maintenance treatment of metastatic colorectal cancer, significantly improved the overall survival and progression-free survival of patients, and the resulting side effects were easily treatable.

Protein array profiling of circulating angiogenesis-related factors during bevacizumab containing treatment in metastatic colorectal cancer

BACKGROUND

Prolonged angiogenesis inhibition may improve treatment outcome in metastatic colorectal cancer (mCRC) patients. However, due to the complexity of the angiogenic pathways there is a lack of valid predictive biomarkers for anti-angiogenic agents. Here, we describe and optimize a procedure for simultaneous dynamic profiling of multiple angiogenesis related proteins in patient serum to explore associations with the response and acquired resistance to anti-angiogenic therapy.

MATERIALS AND METHODS

Patients (n=22) were selected from a clinical trial investigating maintenance treatment with bevacizumab alone after response to induction chemotherapy + bevacizumab in mCRC. Serum samples were analysed for 55 unique angiogenesis related proteins using a commercial proteome profiler array and a publicly available image analysis program for quantification. Samples were collected at baseline before induction treatment start, at start of maintenance treatment, and at end of treatment after tumour progression.

MAIN RESULTS AND CONCLUSION

For eight proteins, the antibody array signals were below detection range in all patient samples. None of the proteins showed levels at baseline or at start of maintenance with strong evidence for correlation to time to progression (lowest nominal p-value 0.03). The dynamic ranges of protein levels measured during the induction treatment period and during the maintenance period were analysed separately for time trends. Evidence for changing trends (up/down) in the levels of MMP-8, TIMP-4 and EGF was observed both during response to induction treatment and at progressive disease, respectively. For three of the proteins (IL-8, Activin A and IGFBP-2), weak evidence for correlation between increasing protein levels during induction with chemotherapy and bevacizumab and time to progression was observed. In conclusion, semi-quantitative profiling of angiogenesis related proteins in patient serum may be a versatile tool to screen for protein patterns aiming at identifying resistance mechanisms of anti-angiogenic treatment in patients with mCRC.

Duration of first-line treatment for metastatic colorectal cancer: Translating the available evidence into general recommendations for routine practice

Over the last two decades the number of front-line regimens for metastatic colorectal cancer has progressively increased. Nevertheless, there is still no consensus on the optimal duration of treatment or the role of de-escalated/maintenance strategies after induction chemotherapy. In this article we provide an overview of the studies that addressed the duration of first-line systemic treatment with cytotoxic agents plus or minus targeted therapies highlighting caveats and limitations of the same. Also, we try to translate the available evidence into practical recommendations that can be used in everyday practice to inform treatment decisions. The main conclusion of our review article is that continuing induction treatment until progression may improve disease control but there is no evidence to suggest that adopting this practice can prolong survival. On the other hand, de-escalated treatment strategies offer an opportunity to reduce the burden of toxicity while maintaining satisfactory oncological outcomes.

Reporting of patient characteristics and stratification factors in phase 3 trials investigating first-line systemic treatment of metastatic colorectal cancer: A systematic review

BACKGROUND

Patient characteristics and stratification factors are important factors influencing trial outcomes. Uniform reporting on these parameters would facilitate cross-study comparisons and extrapolation of trial results to clinical practice. In 2007, standardisation on patient characteristics reporting and stratification in metastatic colorectal cancer (mCRC) trials was proposed. We investigated the reporting of prognostic factors and implementation of this proposal in mCRC trials published from 2005 to 2016.

METHODS

We searched PubMed and Embase (January 2005 - June 2016) for first-line phase 3 mCRC trials. Patient characteristics reporting and use of stratification factors were extracted and analysed for adherence to the proposal from 2007.

RESULTS

Sixty-seven trials (35,315 patients) were identified, reporting 48 different patient characteristics (median: 9 [range: 5-18] per study). Age, gender, performance status (PS), primary tumour site and adjuvant chemotherapy were frequently reported (87%-100%), in contrast to laboratory values, such as alkaline phosphatase, lactate dehydrogenase and white blood cell count (10%-25%). We identified 29 different stratification factors (median: 3 [range: 1-9] per study). The most common strata were PS and treatment centre (>60%). A median of 8/12 (range: 4-11) of the proposed parameters was reported. Although the percentage of studies reporting each factor slightly increased over time, there was no significant correlation between publication year and adherence to the proposal from 2007.

CONCLUSIONS

We observed persistent heterogeneity in the reporting of patient characteristics and use of stratification factors in first-line mCRC trials. The proposal from 2007 has not led to increased uniformity of patient characteristics reporting and use of stratification over time. There is an urgent need to address this issue to improve the interpretation of trial results.

Targeting HER2 in colorectal cancer: The landscape of amplification and short variant mutations in ERBB2 and ERBB3

BACKGROUND

In contrast to lung cancer, few precision treatments are available for colorectal cancer (CRC). One rapidly emerging treatment target in CRC is ERBB2 (human epidermal growth factor receptor 2 [HER2]). Oncogenic alterations in HER2, or its dimerization partner HER3, can underlie sensitivity to HER2-targeted therapies.

METHODS

In this study, 8887 CRC cases were evaluated by comprehensive genomic profiling for genomic alterations in 315 cancer-related genes, tumor mutational burden, and microsatellite instability. This cohort included both colonic (7599 cases; 85.5%) and rectal (1288 cases; 14.5%) adenocarcinomas.

RESULTS

A total of 569 mCRCs were positive for ERBB2 (429 cases; 4.8%) and/or ERBB3 (148 cases; 1.7%) and featured ERBB amplification, short variant alterations, or a combination of the 2. High tumor mutational burden (≥20 mutations/Mb) was significantly more common in ERBB-mutated samples, and ERBB3-mutated CRCs were significantly more likely to have high microsatellite instability (P<.002). Alterations affecting KRAS (27.3%) were significantly underrepresented in ERBB2-amplified samples compared with wild-type CRC samples (51.8%), and ERBB2- or ERBB3-mutated samples (49.0% and 60.8%, respectively) (P<.01). Other significant differences in mutation frequency were observed for genes in the PI3K/MTOR and mismatch repair pathways.

CONCLUSIONS

Although observed less often than in breast or upper gastrointestinal carcinomas, indications for which anti-HER2 therapies are approved, the percentage of CRC with ERBB genomic alterations is significant. Importantly, 32% of ERBB2-positive CRCs harbor short variant alterations that are undetectable by routine immunohistochemistry or fluorescence in situ hybridization testing. The success of anti-HER2 therapies in ongoing clinical trials is a promising development for patients with CRC. Cancer 2018;124:1358-73. © 2018 Foundation Medicine, Inc. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

A Randomized Phase II Study of Axitinib as Maintenance Therapy After First-line Treatment for Metastatic Colorectal Cancer

INTRODUCTION

The aim of this study was to evaluate the efficacy and safety of maintenance therapy with axitinib versus placebo following induction therapy in patients with metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

In this double-blinded, phase II trial, patients with mCRC who had not progressed after 6 to 8 months of first-line chemotherapy were randomized to receive axitinib (5 mg twice a day) (arm A) or placebo (arm B).

RESULTS

Forty-nine patients were included: 25 in arm A and 24 in arm B. The median follow-up was 26.07 months (95% confidence interval [CI], 18.44-31.73 months). Progression-free survival (PFS) rate at 6 months was 40.00% (95% CI, 21.28%-58.12%) in the axitinib arm versus 8.33% (95% CI, 1.44%-23.30%) in the placebo arm (P = .0141). The median PFS was statistically significantly longer in the axitinib group than in the placebo group (4.96 vs. 3.16 months; hazard ratio, 0.46; 95% CI, 0.25-0.86; P = .0116). Median overall survival was also longer in the axitinib arm but did not reach statistical significance (27.61 vs. 19.99 months; hazard ratio, 0.68; 95% CI, 0.31-1.48; P = .3279). Grade 3 to 4 treatment-related toxicities were experienced by 7 patients (28%) in cohort A and 1 patient (4%) in cohort B (P = .0488). The most frequent grade 3 to 4 treatment-related toxicities were hypertension, diarrhea, and asthenia. There were no toxic deaths. The study was prematurely closed because of slow recruitment.

CONCLUSIONS

In our study, maintenance treatment with axitinib monotherapy showed a significant increase in PFS and a good safety profile. Axitinib should be further explored as a possible option for first-line chemotherapy maintenance treatment in patients with mCRC.

Meta-analysis comparing maintenance strategies with continuous therapy and complete chemotherapy-free interval strategies in the treatment of metastatic colorectal cancer

There is as yet no consensus as to the best choice among the three treatment options (maintenance, complete chemotherapy-free intervals [CFIs], and continuous) for metastatic colorectal cancer (CRC). We performed a meta-analysis of six trials (N = 2, 454 patients) to compare the safety and efficacy of those three treatment strategies. Maintenance appeared to offer an advantage over CFI with respect to progression-free survival (PFS) (hazard ratio [HR]: 0.53, 95% confidence interval [CI], 0.40–0.69). PFS and overall survival (OS) were comparable between the maintenance and continuous strategies (HR: 1.18, 95% CI, 0.96–1.46; HR: 1.05, 95% CI, 0.98–1.27, respectively), as was OS between the maintenance and CFI strategies (HR: 0.84; 95% CI, 0.70–1.00). The incidence of grade 3/4 toxicity, including neutropenia, neuropathy, hand-foot syndrome and fatigue, was lower with maintenance than with continuous therapy. A maintenance regimen utilizing bevacizumab-based doublets appeared to confer a slight advantage over bevacizumab monotherapy with respect to PFS (P = 0.011). Maintenance appeared to reduce cumulative grade 3/4 toxicity as compared to the continuous strategy, while showing comparable efficacy. Bevacizumab-based doublets appeared to be of particular value in patients with metastatic CRC.

Dosing de novo combinations of two targeted drugs: Towards a customized precision medicine approach to advanced cancers

Metastatic cancers harbor complex genomic alterations. Thus, monotherapies are often suboptimal. Individualized combinations are needed in order to attenuate resistance. To help inform selection of safe starting doses for novel, two-agent, targeted drug combinations, we identified clinical trials in adult oncology patients who received targeted drug doublets (PubMed, January 1, 2010 through December 31, 2013). The dose percentage was calculated for each drug: (safe dose in combination divided by single agent full dose) X 100. Additive dose percentage represented the sum of the dose percentage for each drug. A total of 144 studies (N = 8568 patients; 95 combinations) were analyzed. In 51% of trials, each of the two drugs could be administered at 100% of their full dose. The lowest safe additive dose percentage was 60% if targets and/or class of drugs overlapped, or in the presence of mTor inhibitors, which sometimes compromised the combination dose. If neither class nor target overlapped and if mTor inhibitors were absent, the lowest safe additive dose percentage was 143%. The current observations contribute to the knowledge base that informs safe starting doses for new combinations of targeted drugs in the context of clinical trials or practice, hence facilitating customized combination therapies.

Continuum of care strategy in metastatic colorectal cancer: a review

Treatment of human metastatic colorectal cancer (mCRC) has changed remarkably in the past two decades. The use of novel therapies and more complex treatment strategies have contributed to progressively increase the median life expectancy of patients up to approximately 30 months. Although traditional cytotoxic chemotherapy and newer targeted therapy are now available for use in treating patients with mCRC, the optimal treatment strategy remains unknown. In recent years, there has been a treatment paradigm shift for mCRC patients with the emergence of the concept of ‘continuum of care’ as the optimal palliative therapy strategy. It is based on the concept whereby patients are exposed throughout the course of their disease to different active drugs; the therapy is personalized according to the need for rapid response, the burden of disease and molecular subtype status, such as RAS, BRAF, MMR and HER2. Drugs are often reintroduced if they demonstrated activity in a previous line of therapy, and most importantly, maintenance chemotherapy and/or intermittent therapy are considered. This review details available data for the use of the continuum of care strategy in mCRC, in which the strategy has provided significant clinical benefit in clinical studies. As our understanding advances, optimal treatment strategy for the patients with mCRC should still be individualized.

Clinical Relevance of Alternative Endpoints in Colorectal Cancer First-Line Therapy With Bevacizumab: A Retrospective Study

BACKGROUND

We studied the relationship between intermediate criteria and overall survival (OS) in metastatic colorectal cancer (mCRC) patients who received first-line chemotherapy with bevacizumab.

PATIENTS AND METHODS

We assessed OS, progression-free survival (PFS), duration of disease control (DDC), the sum of the periods in which the disease did not progress, and the time to failure of strategy (TFS), which was defined as the entire period before the introduction of a second-line treatment. Linear correlation and regression models were used, and Prentice criteria were investigated.

RESULTS

With a median follow-up of 57.6 months for 216 patients, the median OS was 24.5 months (95% confidence interval [CI], 21.3-29.7). The median PFS, DDC, and TFS were 8.9 (95% CI, 8.4-9.7), 11.0 (95% CI, 9.8-12.4), and 11.1 (95% CI, 10.0-13.0) months, respectively. The correlations between OS and DDC (Pearson coefficient, 0.79 [95% CI, 0.73-0.83], determination coefficient, 0.62) and OS and TFS (Pearson coefficient, 0.79 [95% CI, 0.73-0.84], determination coefficient, 0.63) were satisfactory. Linear regression analysis showed a significant association between OS and DDC, and between OS and TFS. Prentice criteria were verified for TFS as well as DDC.

CONCLUSION

DDC and TFS correlated with OS and are relevant as intermediate criteria in the setting of patients with mCRC treated with a first-line bevacizumab-based regimen.

Role of VEGFA gene polymorphisms in colorectal cancer patients who treated with bevacizumab

Objectives

This study aimed to explore the effects of vascular endothelial growth factor A (VEGFA) gene polymorphisms (rs699947 and rs833061) on Bevacizumab (BEV) treatment in colorectal cancer (CRC) patients.

Methods

125 CRC cases receiving BEV plus FOLFIRI treatment were recruited in this study. VEGFA polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Correlation of VEGFA gene polymorphisms with the response rate and progression free survival (PFS) was evaluated. Multivariate analyses were performed to estimate the effects of VEGFA polymorphisms on the therapeutic effects of BEV treatment in CRC patients.

Results

Rs699947 variants did not show significant association with BEV treatment. For rs833061 analysis, TT and TC genotype carriers had significantly higher ORR (objective response rate) than CC carriers (P=0.048 and P=0.021, respectively). Moreover, TT carriers underwent a well DCR (disease control rate) compared to CC carriers (P=0.002). PFS time also showed obvious correlation with rs833061 polymorphism (log rank test, P=0.002). Multivariate analyses demonstrated that TT and TC genotypes of rs833061 polymorphism were significantly correlated with enhanced therapeutic effects and prolonged PFS in CRC patients.

Conclusion

VEGFA rs833061 polymorphism is significantly associated with the therapeutic efficiency of bevacizumab in CRC patients.

A phase II clinical study of combining FOLFIRI and bevacizumab plus erlotinib in 2nd-line chemotherapy for patients with metastatic colorectal cancer

We conducted an open-label single-arm phase II study by combining irinotecan (FOLFIRI) and bevacizumab (BV) plus erlotinib (ER) in 2nd-line chemotherapy for patients with metastatic colorectal cancer (mCRC).Eligible mCRC patients received 1st-line standard chemotherapy but still had progressive disease. They were given FOLFIRI plus BV at 2.5 mg/kg on day 1 per 2-week cycle, and daily 150 mg ER. The primary endpoint is progression-free survival (PFS).A total of 122 patients enrolled in the study. Among them, 55.7% were male patients and median age was 58.4 years (29-72 years). Median PFS was 7.1 months (95% CI 4.3-10.2). Median overall survival (OS) was 13.5 months (95% CI 9.7-16.4). No patients had complete responses, 24 patients had partial response (19.6%) and 59 had stable disease (48.4%). The most frequent adverse event (AE) was rash, with 66 patients (54.1%) had grade 3/4 rash. Other frequent grade 3/4 AEs were fatigue (n = 36, 29.5%), bleeding (n = 31, 25.4%), neutropenia (n = 23, 18.9%), and platelets (n = 14, 11.5%).Combining FOLFIRI and BV plus ER in 2nd-line chemotherapy is efficient to treat mCRC patients with acceptable safety.

Epidermal growth factor receptor (EGFR) inhibitors for metastatic colorectal cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) inhibitors prevent cell growth and have shown benefit in the treatment of metastatic colorectal cancer, whether used as single agents or in combination with chemotherapy. Clear benefit has been shown in trials of EGFR monoclonal antibodies (EGFR MAb) but not EGFR tyrosine kinase inhibitors (EGFR TKI). However, there is ongoing debate as to which patient populations gain maximum benefit from EGFR inhibition and where they should be used in the metastatic colorectal cancer treatment paradigm to maximise efficacy and minimise toxicity.

OBJECTIVES

To determine the efficacy, safety profile, and potential harms of EGFR inhibitors in the treatment of people with metastatic colorectal cancer when given alone, in combination with chemotherapy, or with other biological agents.The primary outcome of interest was progression-free survival; secondary outcomes included overall survival, tumour response rate, quality of life, and adverse events.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Library, Issue 9, 2016; Ovid MEDLINE (from 1950); and Ovid Embase (from 1974) on 9 September 2016; and ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) on 14 March 2017. We also searched proceedings from the major oncology conferences ESMO, ASCO, and ASCO GI from 2012 to December 2016. We further scanned reference lists from eligible publications and contacted corresponding authors for trials for further information where needed.

SELECTION CRITERIA

We included randomised controlled trials on participants with metastatic colorectal cancer comparing: 1) the combination of EGFR MAb and 'standard therapy' (whether chemotherapy or best supportive care) to standard therapy alone, 2) the combination of EGFR TKI and standard therapy to standard therapy alone, 3) the combination of EGFR inhibitor (whether MAb or TKI) and standard therapy to another EGFR inhibitor (or the same inhibitor with a different dosing regimen) and standard therapy, or 4) the combination of EGFR inhibitor (whether MAb or TKI), anti-angiogenic therapy, and standard therapy to anti-angiogenic therapy and standard therapy alone.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures defined by Cochrane. Summary statistics for the endpoints used hazard ratios (HR) with 95% confidence intervals (CI) for overall survival and progression-free survival, and odds ratios (OR) for response rate (RR) and toxicity. Subgroup analyses were performed by Kirsten rat sarcoma viral oncogene homolog (KRAS) and neuroblastoma RAS viral (V-Ras) oncogene homolog (NRAS) status - firstly by status of KRAS exon 2 testing (mutant or wild type) and also by status of extended KRAS/NRAS testing (any mutation present or wild type).

MAIN RESULTS

We identified 33 randomised controlled trials for analysis (15,025 participants), including trials of both EGFR MAb and EGFR TKI. Looking across studies, significant risk of bias was present, particularly with regard to the risk of selection bias (15/33 unclear risk, 1/33 high risk), performance bias (9/33 unclear risk, 9/33 high risk), and detection bias (7/33 unclear risk, 11/33 high risk).The addition of EGFR MAb to standard therapy in the KRAS exon 2 wild-type population improves progression-free survival (HR 0.70, 95% CI 0.60 to 0.82; high-quality evidence), overall survival (HR 0.88, 95% CI 0.80 to 0.98; high-quality evidence), and response rate (OR 2.41, 95% CI 1.70 to 3.41; high-quality evidence). We noted evidence of significant statistical heterogeneity in all three of these analyses (progression-free survival: I² = 76%; overall survival: I² = 40%; and response rate: I² = 77%), likely due to pooling of studies investigating EGFR MAb use in different lines of therapy. Rates of overall grade 3 to 4 toxicity, diarrhoea, and rash were increased (moderate-quality evidence for all three outcomes), but there was no evidence for increased rates of neutropenia.For the extended RAS wild-type population (no mutations in KRAS or NRAS), addition of EGFR MAb improved progression-free survival (HR 0.60, 95% CI 0.48 to 0.75; moderate-quality evidence) and overall survival (HR 0.77, 95% CI 0.67 to 0.88; high-quality evidence). Response rate was also improved (OR 4.28, 95% CI 2.61 to 7.03; moderate-quality evidence). We noted significant statistical heterogeneity in the progression-free survival analysis (I² = 61%), likely due to the pooling of studies combining EGFR MAb with chemotherapy with monotherapy studies.We observed no evidence of a statistically significant difference when EGFR MAb was compared to bevacizumab, in progression-free survival (HR 1.02, 95% CI 0.93 to 1.12; high quality evidence) or overall survival (HR 0.84, 95% CI 0.70 to 1.01; moderate-quality evidence). We noted significant statistical heterogeneity in the overall survival analysis (I² = 51%), likely due to the pooling of first-line and second-line studies.The addition of EGFR TKI to standard therapy in molecularly unselected participants did not show benefit in limited data sets (meta-analysis not performed). The addition of EGFR MAb to bevacizumab plus chemotherapy in people with KRAS exon 2 wild-type metastatic colorectal cancer did not improve progression-free survival (HR 1.04, 95% CI 0.83 to 1.29; very low quality evidence), overall survival (HR 1.00, 95% CI 0.69 to 1.47; low-quality evidence), or response rate (OR 1.20, 95% CI 0.67 to 2.12; very low-quality evidence) but increased toxicity (OR 2.57, 95% CI 1.45 to 4.57; low-quality evidence). We noted significant between-study heterogeneity in most analyses.Scant information on quality of life was reported in the identified studies.

AUTHORS' CONCLUSIONS

The addition of EGFR MAb to either chemotherapy or best supportive care improves progression-free survival (moderate- to high-quality evidence), overall survival (high-quality evidence), and tumour response rate (moderate- to high-quality evidence), but may increase toxicity in people with KRAS exon 2 wild-type or extended RAS wild-type metastatic colorectal cancer (moderate-quality evidence). The addition of EGFR TKI to standard therapy does not improve clinical outcomes. EGFR MAb combined with bevacizumab is of no clinical value (very low-quality evidence). Future studies should focus on optimal sequencing and predictive biomarkers and collect quality of life data.

Epidermal growth factor receptor (EGFR) inhibitors for metastatic colorectal cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) inhibitors prevent cell growth and have shown benefit in the treatment of metastatic colorectal cancer, whether used as single agents or in combination with chemotherapy. Clear benefit has been shown in trials of EGFR monoclonal antibodies (EGFR MAb) but not EGFR tyrosine kinase inhibitors (EGFR TKI). However, there is ongoing debate as to which patient populations gain maximum benefit from EGFR inhibition and where they should be used in the metastatic colorectal cancer treatment paradigm to maximise efficacy and minimise toxicity.

OBJECTIVES

To determine the efficacy, safety profile, and potential harms of EGFR inhibitors in the treatment of people with metastatic colorectal cancer when given alone, in combination with chemotherapy, or with other biological agents.The primary outcome of interest was progression-free survival; secondary outcomes included overall survival, tumour response rate, quality of life, and adverse events.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Library, Issue 9, 2016; Ovid MEDLINE (from 1950); and Ovid Embase (from 1974) on 9 September 2016; and ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) on 14 March 2017. We also searched proceedings from the major oncology conferences ESMO, ASCO, and ASCO GI from 2012 to December 2016. We further scanned reference lists from eligible publications and contacted corresponding authors for trials for further information where needed.

SELECTION CRITERIA

We included randomised controlled trials on participants with metastatic colorectal cancer comparing: 1) the combination of EGFR MAb and 'standard therapy' (whether chemotherapy or best supportive care) to standard therapy alone, 2) the combination of EGFR TKI and standard therapy to standard therapy alone, 3) the combination of EGFR inhibitor (whether MAb or TKI) and standard therapy to another EGFR inhibitor (or the same inhibitor with a different dosing regimen) and standard therapy, or 4) the combination of EGFR inhibitor (whether MAb or TKI), anti-angiogenic therapy, and standard therapy to anti-angiogenic therapy and standard therapy alone.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures defined by Cochrane. Summary statistics for the endpoints used hazard ratios (HR) with 95% confidence intervals (CI) for overall survival and progression-free survival, and odds ratios (OR) for response rate (RR) and toxicity. Subgroup analyses were performed by Kirsten rat sarcoma viral oncogene homolog (KRAS) and neuroblastoma RAS viral (V-Ras) oncogene homolog (NRAS) status - firstly by status of KRAS exon 2 testing (mutant or wild type) and also by status of extended KRAS/NRAS testing (any mutation present or wild type).

MAIN RESULTS

We identified 33 randomised controlled trials for analysis (15,025 participants), including trials of both EGFR MAb and EGFR TKI. Looking across studies, significant risk of bias was present, particularly with regard to the risk of selection bias (15/33 unclear risk, 1/33 high risk), performance bias (9/33 unclear risk, 9/33 high risk), and detection bias (7/33 unclear risk, 11/33 high risk).The addition of EGFR MAb to standard therapy in the KRAS exon 2 wild-type population improves progression-free survival (HR 0.70, 95% CI 0.60 to 0.82; high-quality evidence), overall survival (HR 0.88, 95% CI 0.80 to 0.98; high-quality evidence), and response rate (OR 2.41, 95% CI 1.70 to 3.41; high-quality evidence). We noted evidence of significant statistical heterogeneity in all three of these analyses (progression-free survival: I2 = 76%; overall survival: I2 = 40%; and response rate: I2 = 77%), likely due to pooling of studies investigating EGFR MAb use in different lines of therapy. Rates of overall grade 3 to 4 toxicity, diarrhoea, and rash were increased (moderate-quality evidence for all three outcomes), but there was no evidence for increased rates of neutropenia.For the extended RAS wild-type population (no mutations in KRAS or NRAS), addition of EGFR MAb improved progression-free survival (HR 0.60, 95% CI 0.48 to 0.75; moderate-quality evidence) and overall survival (HR 0.77, 95% CI 0.67 to 0.88; high-quality evidence). Response rate was also improved (OR 4.28, 95% CI 2.61 to 7.03; moderate-quality evidence). We noted significant statistical heterogeneity in the progression-free survival analysis (I2 = 61%), likely due to the pooling of studies combining EGFR MAb with chemotherapy with monotherapy studies.We observed no evidence of a statistically significant difference when EGFR MAb was compared to bevacizumab, in progression-free survival (HR 1.02, 95% CI 0.93 to 1.12; high quality evidence) or overall survival (HR 0.84, 95% CI 0.70 to 1.01; moderate-quality evidence). We noted significant statistical heterogeneity in the overall survival analysis (I2 = 51%), likely due to the pooling of first-line and second-line studies.The addition of EGFR TKI to standard therapy in molecularly unselected participants did not show benefit in limited data sets (meta-analysis not performed). The addition of EGFR MAb to bevacizumab plus chemotherapy in people with KRAS exon 2 wild-type metastatic colorectal cancer did not improve progression-free survival (HR 1.04, 95% CI 0.83 to 1.29; very low quality evidence), overall survival (HR 1.00, 95% CI 0.69 to 1.47; low-quality evidence), or response rate (OR 1.20, 95% CI 0.67 to 2.12; very low-quality evidence) but increased toxicity (OR 2.57, 95% CI 1.45 to 4.57; low-quality evidence). We noted significant between-study heterogeneity in most analyses.Scant information on quality of life was reported in the identified studies.

AUTHORS' CONCLUSIONS

The addition of EGFR MAb to either chemotherapy or best supportive care improves progression-free survival (moderate- to high-quality evidence), overall survival (high-quality evidence), and tumour response rate (moderate- to high-quality evidence), but may increase toxicity in people with KRAS exon 2 wild-type or extended RAS wild-type metastatic colorectal cancer (moderate-quality evidence). The addition of EGFR TKI to standard therapy does not improve clinical outcomes. EGFR MAb combined with bevacizumab is of no clinical value (very low-quality evidence). Future studies should focus on optimal sequencing and predictive biomarkers and collect quality of life data.

Management of adverse events during treatment of gastrointestinal cancers with epidermal growth factor inhibitors

The epidermal growth factor receptor (EGFR) is involved in development and progression of some gastrointestinal cancers, and is targeted by monoclonal antibodies (mAbs) and tyrosine kinase inhibitors (TKIs) used to treat these conditions. Targeted agents are generally better tolerated than conventional chemotherapy, but have characteristic toxicities that can affect adherence, dosing, and outcomes. Skin conditions are the most common toxicities associated with EGFR inhibitors, particularly papulopustular rash. Other common toxicities include mucosal toxicity, electrolyte imbalances (notably hypomagnesaemia), and diarrhoea, while the chimaeric mAb cetuximab is also associated with increased risk of infusion reactions. With appropriate prophylaxis, the incidence and severity of these events can be reduced, while management strategies tailored to the patient and the degree of toxicity can help to ensure continuation of anti-cancer therapy. Here, we review the main toxicities associated with EGFR-inhibiting mAbs and TKIs in patients with gastrointestinal cancers, and provide recommendations for prophylaxis and treatment.

Survival Benefit and Safety of Bevacizumab in Combination with Erlotinib as Maintenance Therapy in Patients with Metastatic Colorectal Cancer: A Meta-Analysis

BACKGROUND

Recently, the need for maintenance chemotherapy arose as a result of the significantly improved survival of patients with metastatic colorectal cancer (mCRC) without increasing adverse events. Currently used maintenance regimens are fluoropyrimidines, bevacizumab, and the combination of fluoropyrimidine with bevacizumab. A new combination with bevacizumab and erlotinib, a tyrosine kinase inhibitor of the epithelial growth factor receptor, has shown synergistic effects in preclinical tests and promising results in some clinical trials. Whether bevacizumab combined with erlotinib vs. bevacizumab alone as maintenance therapy will further improve the clinical outcomes in patients with mCRC is controversial. We conducted this meta-analysis to compare the survival benefit and safety of these two regimens in patients with mCRC.

METHODS

We searched PubMed, EMBASE, and the Central Registry of Controlled Trials of the Cochrane Library up to August 2016. We also searched the Proceedings of the American Society of Clinical Oncology (1986 to August 2016). Abstracts were manually searched to identify relevant trials. A total of three randomized controlled trials with 682 patients met the inclusion criteria.

RESULTS

Our results demonstrated that bevacizumab combined with erlotinib significantly improved overall survival (hazard ratio 0.78; 95 % confidence interval 0.66-0.93; p = 0.006) and progression-free survival (hazard ratio 0.79; 95 % confidence interval 0.68-0.92; p = 0.002). Significantly more grade 3 rash, diarrhea, infection total, and fatigue were observed in the bevacizumab combined with erlotinib arm, which were controllable and reversible.

CONCLUSIONS

Based on current evidence, the addition of erlotinib to bevacizumab as maintenance therapy significantly increases overall survival and progression-free survival with an increased but manageable toxicity in patients with mCRC. It should be considered as a treatment option for these patients under the premise of a reasonable selection of the target population.

Unravelling the pharmacologic opportunities and future directions for targeted therapies in gastro-intestinal cancers Part 1: GI carcinomas

Until the 1990s, cytotoxic chemotherapy has been the cornerstone of medical therapy for gastrointestinal (GI) cancers. Better understanding of the molecular biology of cancer cell has led to the therapeutic revolution of targeted therapies, i.e. monoclonal antibodies or small molecule inhibitors directed against proteins that are specifically overexpressed or mutated in cancer cells. These agents being more specific to cancer cells were expected to be less toxic than cytotoxic agents. Targeted agents have provided clinical benefit in many GI cancer types. For example, antiangiogenics and anti-EGFR therapies have significantly improved survival of patients affected by metastatic colorectal cancer and have deeply changed the therapeutic strategy in this disease. However, their effects have sometimes been disappointing, due to intrinsic or acquired resistance mechanisms (e.g., RAS mutation for anti-EGFR therapies), or to an activity restricted to some tumour settings (e.g., lack of activity in other cancer types, or on the microscopic residual disease in adjuvant setting). Many studies are negative in overall population but positive in some specific patient subgroups (e.g., trastuzumab in HER2-positive gastric cancer), illustrating the importance of patient selection and early identification of predictive biomarkers of response to these therapies. We propose a comprehensive two-part review providing a panoramic approach of the successes and failures of targeted agents in GI cancers to unravel the pharmacologic opportunities and future directions for these agents in GI oncology. In this first part, we will focus on adenocarcinomas and squamous cell carcinomas, for which targeted therapies are mostly used in combination with chemotherapy.

Bevacizumab maintenance treatment for colorectal cancer: A meta-analysis

AIM

to perform a meta-analysis to evaluate the efficacy and safety of bevacizumab in the maintenance treatment of colorectal cancer.

METHODS

Literature retrieval was conducted by searching Cochrane Controlled Trials Register (CCTR), MEDLINE (1994-August 2016), Chinese Biomedical database (1978-August 2016) and CNKI (1994-August 2016). The quality of included articles was assessed based on the approach commended by the International Cochrane Collaboration. Statistical analysis was performed using RevMan5.0 software.

RESULTS

Eight randomized controlled clinical trials were included, but concealed allocation was not mentioned in all of them. Although loss to follow-up was reported and intention-to-treat analysis was conducted in all the included articles, blinding method was covered only in one paper. Compared with chemotherapy alone, chemotherapy combined with bevacizumab was associated with prolonged progression free survival (PFS; HR = 0.76, 95%CI: 0.64-0.90) and median overall survival (OS; HR = 0.82, 95%CI: 0.74-0.89). After six cycles of XELOX (capecitabine, oxaliplatin, and fluorouracil) + bevacizumab, the patients received maintenance therapy comprising either XELOX + bevacizumab or capecitabine + bevacizumab (PFS: HR = 1.68, 95%CI: 1.21-2.35; OS: HR = 1.38, 95%CI: 0.91-2.08). In patients who had disease progression after first-line chemotherapy combined with bevacizumab, bevacizumab combined with second-line maintenance chemotherapy provided survival advantage (PFS: HR = 0.76, 95%CI: 0.69-0.83; OS: HR = 0.83, 95%CI: 0.72-0.95). chemotherapy plus bevacizumab increased the incidence of grade 3-4 toxicities (RR = 1.19, 95%CI: 1.11-1.28).

CONCLUSION

Bevacizumab combined with chemotherapy can improve the PFS and OS in the treatment of metastatic colorectal cancer, but increases the incidence of grade 3-4 toxicities.

Does bevacizumab impact anti-EGFR therapy efficacy in metastatic colorectal cancer?

Anti-EGFR therapy and antiangiogenic therapies are used alone or in combination with chemotherapies to improve survival in metastatic colorectal cancer. However, it is unknown whether pretreatment with antiangiogenic therapy could impact on the efficacy of anti-EGFR therapy.

We selected one hundred and twenty eight patients diagnosed with advanced colorectal cancer with a KRAS and NRAS unmutated tumor. These patients were treated with cetuximab or panitumumab alone or with chemotherapy as second or third-line. Univariate and multivariate Cox model analysis were performed to estimate the effect of a previous bevacizumab regimen on progression free survival and on overall survival during anti-EGFR therapy. In vitro studies using wild type KRAS and NRAS colon cancer cells were performed to evaluate the impact of VEGF-A on cetuximab-induced cell death.

The median progression free survival (PFS) during anti-EGFR treatment was significantly different between the bevacizumab group and the non-bevacizumab group (2.8 and 4 months respectively; p = 0.003). The median overall survival from the beginning of the metastatic disease was similar in the two groups (41.3 and 42 months respectively; p = 0.7). In vitro, VEGF-A induced a resistance toward cetuximab cytotoxicity on three KRAS and NRAS wild type colon cancer cell lines in a VEGFR2 and Stat-3-dependent manner.

All in all, our clinical data, supported by in vitro procedures, suggest that a previous anti-VEGF therapy decreases anti-EGFR efficacy. Although these results are observed in a limited cohort, they could be taken into consideration for a better strategy of care for patient suffering from metastatic colorectal cancer.

Risk of severe rash in cancer patients treated with EGFR tyrosine kinase inhibitors: a systematic review and meta-analysis

Aim: We performed a meta-analysis to evaluate the incidence and risk factors of severe rash associated with the use of EGFR tyrosine kinase inhibitors (TKIs). Methods: PubMed, EMBASE and oncology conference proceedings were searched for articles published till March 2016. Results: A total of 18,309 patients from 37 randomized controlled trials were available for the meta-analysis. The overall incidence for severe rash was 6.6% (95% CI: 5.2–8.3%) among patients receiving EGFR-TKIs. The use of EGFR-TKIs significantly increased the risk of developing severe rash (risk ratio: 7.70; 95% CI: 5.79–10.23) in cancer patients. On subgroup analysis, the increased risk of severe rash was driven predominantly by drug type (p = 0.002). Conclusion: EGFR-TKIs significantly increase the risk of developing severe rash in cancer patients.

Quality of life assessment in patients with metastatic colorectal cancer receiving maintenance therapy after first-line induction treatment: a preplanned analysis of the phase III AIO KRK 0207 trial

BACKGROUND

First-line maintenance strategies are a current matter of debate in the management of mCRC. Their impact on patient's health-related quality of life (HRQOL) has not yet been evaluated. The objective of this study was to assess whether differences in HRQOL during any active maintenance treatment compared with no maintenance treatment exist.

PATIENT AND METHODS

Eight hundred and thirty-seven patients were enrolled in the AIO KRK 0207 trial. Four hundred and seventy-two underwent randomization (after 24 weeks of induction treatment) into one of the maintenance arms: FP plus Bev (arm A), Bev alone (arm B), or no active treatment (arm C). HRQOL were assessed every 6 weeks during induction and maintenance treatment independent from treatment stop, delay, or modification, and also continued after progression, using the EORTC QLQ-C30, QLQ-CR29. The mean value of the global quality of life dimension (GHS/QoL) of the EORTC QLQ-C30, calculated as the average of all available time points after randomization was considered as pre-specified main endpoint. Additionally, EORTC QLQ-C30 response scores were analyzed.

RESULTS

For HRQOL analysis, 413 patients were eligible (arm A: 136; arm B: 142, arm C: 135). Compliance rate with the HRQOL questionnaires was 95% at time of randomization and remained high during maintenance (98%, 99%, 97% and 97% at week 6, 12, 18 and 24). No significant differences between treatment arms in the mean GHS/QoL scores were observed at any time point. Also, rates of GHS/QoL score deterioration were similar (20.5%; 17.2% and 20.7% of patients), whereas a score improvement occurred in 36.1%; 43.8% and 42.1% (arms A, B and C).

CONCLUSION

Continuation of an active maintenance treatment with FP/Bev after induction treatment was neither associated with a detrimental effect on GHS/QoL scores when compared with both, less active treatment with Bev alone or no active treatment.

CLINICAL TRIALS NUMBER

NCT00973609 (ClinicalTrials.gov).

Emerging tyrosine kinase inhibitors for the treatment of metastatic colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is a leading cause of cancer death worldwide. Over the last decade, the addition of antibodies that block the epidermal growth factor receptor (EGFR) or angiogenesis to the classic chemotherapy backbone has improved overall survival in metastatic colorectal cancer (mCRC). However, the role of the other major targeted therapy, the tyrosine kinase inhibitors (TKIs), is not yet fully clarified.

AREAS COVERED

This review discusses key published and ongoing studies with TKIs in mCRC, the mechanisms of resistance to standard treatments that are potentially targetable with these small molecules, along with the role of biomarkers in therapeutic decision-making process.

EXPERT OPINION

The current effectiveness of TKIs is limited by two principal reasons, firstly the use of combination chemotherapy necessitates lower dose-density to manage the toxicity profile and secondly, development of these drugs has mainly been performed in molecularly unselected populations. mCRC is a heterogeneous and dynamic disease, and clinical trials with TKIs must be designed on the basis of specific molecular alterations targeted by these drugs. Success with this approach relies on identifying mutations at the time of progression, raising the importance of minimally-invasive monitoring tools. Liquid biopsies are a promising option, although this technique remains to be validated. Overall, this approach contributes to the move towards personalized and precision therapeutic strategies.

ESMO consensus guidelines for the management of patients with metastatic colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies in Western countries. Over the last 20 years, and the last decade in particular, the clinical outcome for patients with metastatic CRC (mCRC) has improved greatly due not only to an increase in the number of patients being referred for and undergoing surgical resection of their localised metastatic disease but also to a more strategic approach to the delivery of systemic therapy and an expansion in the use of ablative techniques. This reflects the increase in the number of patients that are being managed within a multidisciplinary team environment and specialist cancer centres, and the emergence over the same time period not only of improved imaging techniques but also prognostic and predictive molecular markers. Treatment decisions for patients with mCRC must be evidence-based. Thus, these ESMO consensus guidelines have been developed based on the current available evidence to provide a series of evidence-based recommendations to assist in the treatment and management of patients with mCRC in this rapidly evolving treatment setting.

Maintenance based Bevacizumab versus complete stop or continuous therapy after induction therapy in first line treatment of stage IV colorectal cancer: A meta-analysis of randomized clinical trials

BACKGROUND

In stage IV colorectal cancer, bevacizumab-based maintenance therapy, complete stop therapy and continuous therapy are considered all possible approaches after first line induction chemotherapy. However, there are no clear data about which approach is preferable.

MATERIAL AND METHODS

All randomized phase III trials comparing bevacizumab-based maintenance therapy (MB) with complete stop therapy (ST) or with continuous therapy (CT) were considered eligible and included into the analysis. Primary endpoint was the Time to failure strategies (TFS). Secondary endpoints were Overall Survival (OS) and Progression free survival (PFS). Meta-analysis was performed in line with the PRISMA statement.

RESULTS

1892 patients of five trials were included into the analysis. A significant improvement in TFS (HR 0.79; CI 95% 0.7-0.9 p=0.0005) and PFS (HR 0.56; CI 95% 0.44-0.71 p<0.00001) were observed in favour of MB versus ST. A trend, but not statistically significant, in favour of MB versus ST was also observed for OS (HR 0.88; CI 95% 0.77-1.01, p=0.08). Comparing maintenance therapy versus continuous therapy no statistically differences were observed in the outcomes evaluated (OS 12 months OR 1.1 p=0.62, OS 24 months OR 1 p=1, OS 36 months OR 0.54 p=0.3, TFS 12 months OR 0.76 p=0.65).

CONCLUSIONS

Our meta-analysis suggests that use of MB approach increases TFS, PFS compared to ST. Although without observing any statistically advantage, it should be highlighted that MB versus ST showed a trend in favour of MB. We observed no difference between MB and CT. MB should be considered the standard regimen in patients with stage IV colorectal cancer after first line induction therapy.

Reconsidering the benefit of intermittent versus continuous treatment in the maintenance treatment setting of metastatic colorectal cancer

Colorectal cancer is one of the most frequent solid tumors in the western world, with low survival rates in patients with metastatic disease. Doublet chemotherapy regimens such as FOLFOX or FOLFIRI are the mainstay of standard first-line chemotherapy in the metastatic setting. The conventional treatment as a first-line approach is continuous application until progression or intolerable toxicities. However, only one third of patients are treated until progression mainly due to the side effects of chemotherapy. Notably, oxaliplatin-containing regimens such as FOLFOX/CapOx or FOLFOXIRI are associated with oxaliplatin-induced neuropathy, which is the main reason for treatment discontinuation or treatment de-escalation. On this basis, recent studies have investigated the clinical benefits of bevacizumab-based intermittent and continuous treatment regimens in the metastatic colorectal setting, together with various strategies to optimize maintenance therapy including regimens with targeted therapies, such as cetuximab, ziv-aflibercept and regorafenib. Recent studies have also investigated when maintenance therapy should be initiated as well individualizing treatment based on patient, tumor and treatment characteristics, as well as molecular biomarkers. This article reviews the current evidence for the clinical benefit of intermittent versus continuous treatment in the maintenance treatment setting of metastatic colorectal cancer, and also evaluates the effect of RAS and BRAF mutational status on maintenance strategies.

Effect of Application and Intensity of Bevacizumab-based Maintenance After Induction Chemotherapy With Bevacizumab for Metastatic Colorectal Cancer: A Meta-analysis

BACKGROUND

The administration and intensity of bevacizumab-based maintenance therapy after induction treatment with bevacizumab is still a matter of debate. Thus, the present meta-analysis and an indirect comparison were performed to clarify these issues.

PATIENTS AND METHODS

Trials evaluating a separately defined "maintenance phase," with randomization after the induction phase, were selected. Three trials of maintenance with bevacizumab with or without a fluoropyrimidine (CAIRO3, SAKK 41/06, and AIO KRK 0207) were analyzed regarding the effect on progression-free survival (PFS) and overall survival (OS) of any maintenance therapy compared with observation alone and different maintenance intensities (bevacizumab with or without fluoropyrimidine) compared with observation alone and between each other.

RESULTS

Maintenance with bevacizumab with or without fluoropyrimidine after bevacizumab-based induction treatment for 4 to 6 months significantly improved PFS (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.43-0.75; P = .0004) and showed a trend toward prolonged OS (HR, 0.89; 95% CI, 0.78-1.02; P = .09) compared with observation alone. The effect on PFS increased with the intensity of the maintenance regimen (HR, 0.72; 95% CI, 0.60-0.85 for single-agent bevacizumab vs. HR, 0.45; 95%, CI 0.39-0.51 for combination therapy, both compared to observation alone). In contrast, the HRs for OS remained in the same range. A similarly improved PFS (HR, 0.63; 95% CI, 0.50-0.79) was shown for the more intensive maintenance therapy (bevacizumab and fluoropyrimidine) compared with bevacizumab alone.

CONCLUSION

Bevacizumab-based maintenance therapy after induction chemotherapy with bevacizumab significantly improves PFS and showed a trend toward prolonged OS and should thus be considered, in particular, in patients with a response to induction treatment.

Maintenance strategy in metastatic colorectal cancer: A systematic review

PURPOSE

Colorectal cancer is the third most common cancer in men and second in women, estimated to cause 694,000 deaths worldwide in 2012. Although 5-year survival rate of CRC has increased, inoperable metastatic colorectal cancer (mCRC) is almost always fatal. The aim of this systematic review is to outline the maintenance strategies that increase the chance and duration of survival with less toxicity and sustained quality of life.

DESIGN

Literature search in PubMed, in American Society of Clinical Oncology (ASCO) Annual Meetings and in ASCO Gastrointestinal Symposia and European Society for Medical Oncology (ESMO) Congresses was performed. Studies conducted in adult patients were written in English language and were published in peer-reviewed journals as phase II or III randomized controlled trials (RCTs) comparing continuous chemotherapy to intermittent chemotherapy, each with or without maintenance therapy was included along with at least one of the outcomes of interest.

RESULTS

Twenty randomized controlled trials and systematic reviews were included from Medline search, together with 4 abstracts from ASCO meetings and 2 abstracts from ESMO meetings.

CONCLUSION

Existing evidence-based data show that prolonged progression free survival (PFS) can be achieved with less toxic regimens compared to complete drug holidays or continued treatment. However, the impact of maintenance on overall survival is less clear. The specific data for maintenance with biological agents are evolving, while in general fluoropyrimidine based maintenance with bevacizumab is better than Bev alone or observation for PFS. Data regarding Cetuximab maintenance are less pronounced than that of Bev maintenance. Preliminary data show that erlotinib-Bev combination may be of benefit as maintenance. Although maintenance may provide significant clinical benefit in clinical studies, the optimal strategy should still be individualized.

Bevacizumab in combination with fluoropyrimidine-irinotecan- or fluoropyrimidine-oxaliplatin-based chemotherapy for first-line and maintenance treatment of metastatic colorectal cancer

Despite a slight decrease in mortality rates, recent advances in screening methods, diagnosis and overall improved therapeutic options, colorectal cancer (CRC) remains among the leading causes of cancer-related death worldwide. The major cause is the mortality related to metastatic status of CRC. Increasing clinical evidence derived from randomized trials strongly suggests that the efficacy of standard cytotoxic agents, including various combinations of 5-fluoouracil (5-FU)/leucovorin (LV), capecitabine, irinotecan and oxaliplatin, may be significantly augmented with concomitant administration of molecular agents targeting the vascular endothelial growth factor (VEGF) signaling pathways, such as bevacizumab. Herein, we critically discuss the current data on the efficacy and safety profile of bevacizumab in combination with fluoropyrimidine-based chemotherapy for first-line and maintenance treatment of metastatic CRC and briefly comment on existing controversies and future perspectives.

Bevacizumab with or without erlotinib as maintenance therapy in patients with metastatic colorectal cancer (GERCOR DREAM; OPTIMOX3): a randomised, open-label, phase 3 trial

BACKGROUND

The combination of an anti-VEGF or an anti-EGFR-targeted monoclonal antibody with chemotherapy has shown clinical activity in patients with metastatic colorectal cancer. However, combining both anti-VEGF and anti-EGFR antibodies with chemotherapy in first-line treatment resulted in adverse outcomes. We assessed whether the combination of erlotinib, an EGFR tyrosine kinase inhibitor, with bevacizumab could increase the efficacy of maintenance therapy in patients with unresectable metastatic colorectal cancer.

METHODS

This randomised, open-label, phase 3 study was undertaken in 49 centres in France, Austria, and Canada. Eligible patients were aged 18-80 years with histologically confirmed, unresectable metastatic colorectal cancer, WHO performance status 0-2, had received no previous therapy for metastatic disease, and had adequate organ function. Patients without disease progression after bevacizumab-based induction therapy were randomly assigned (1:1) by a minimisation technique to bevacizumab (7·5 mg/kg every 3 weeks) or bevacizumab plus erlotinib (150 mg once daily) as maintenance therapy until progression. All patients were stratified by centre, baseline performance status, age, and number of metastatic sites. The primary endpoint was progression-free survival on maintenance therapy analysed by intention to treat. We report the final analysis. This trial is registered with ClinicalTrials.gov, number NCT00265824.

FINDINGS

Between Jan 1, 2007, and Oct 13, 2011, 700 eligible patients were enrolled; following induction treatment, patients without disease progression were randomly assigned to bevacizumab (n=228) or bevacizumab plus erlotinib (n=224). At the final analysis, median follow-up was 51·0 months (IQR 36·0-60·0) in the bevacizumab group and 48·3 months (31·5-61·0) in the bevacizumab plus erlotinib group. In the primary analysis (after 231 progression-free survival events), median progression-free survival from randomisation was 5·1 months (95% CI 4·1-5·9) in the bevacizumab plus erlotinib group compared with 6·0 months (4·6-7·9) in the bevacizumab group (stratified hazard ratio [HR] 0·79 [95% CI 0·60-1·06]; p=0·11; unstratified HR 0·76 [0·59-0·99]; p=0·043). In the final analysis, median progression-free survival from randomisation was 5·4 months (95% CI 4·3-6·2) in the bevacizumab plus erlotinib group compared with 4·9 months (4·1-5·7) in the bevacizumab group (stratified HR 0·81 [95% CI 0·66-1·01], p=0·059; unstratified HR 0·78 [0·68-0·96], p=0·019). At the final analysis, median overall survival from maintenance was 24·9 months (95% CI 21·4-28·9) in the bevacizumab plus erlotinib group and 22·1 months (19·6-26·7) in the bevacizumab group (stratified HR 0·79 [95% CI 0·63-0·99], p=0·036; unstratified HR 0·79 [0·64-0·98], p=0·035). The most frequent grade 3-4 adverse events were skin rash (47 [21%] of 220 patients in the bevacizumab plus erlotinib group vs none of 224 patients in the bevacizumab alone group), diarrhoea (21 [10%] vs two [<1%]), and asthenia (12 [5%] vs two [<1%]).

INTERPRETATION

Maintenance bevacizumab plus erlotinib might be a new non-chemotherapy-based maintenance option for the first-line treatment of patients with unresectable metastatic colorectal cancer after bevacizumab-based induction therapy.

FUNDING

GERCOR and F Hoffmann-La Roche.

A randomized study of KRAS-guided maintenance therapy with bevacizumab, erlotinib or metronomic capecitabine after first-line induction treatment of metastatic colorectal cancer: the Nordic ACT2 trial

BACKGROUND

Maintenance treatment (mt) with bevacizumab (bev) ± erlotinib (erlo) has modest effect after induction chemotherapy in metastatic colorectal cancer (mCRC). We hypothesized the efficacy of erlo to be dependent on KRAS mutational status and investigated this by exploring mt strategies with bev ± erlo and low-dose capecitabine (cap).

PATIENTS AND METHODS

Included patients had mCRC scheduled for first-line therapy, Eastern Cooperative Oncology Group (ECOG) 0-1 and no major comorbidities. Treatment with XELOX/FOLFOX or XELIRI/FOLFIRI + bev was given for 18 weeks. After induction, patients without progression were eligible for randomization to mt; KRAS wild-type (wt) patients were randomized to bev ± erlo (arms wt-BE, N = 36 versus wt-B, N = 35), KRAS mutated (mut) patients were randomized to bev or metronomic cap (arms mut-B, N = 34 versus mut-C, N = 33). Primary end point was progression-free survival (PFS) rate (PFSr) at 3 months after start of mt. A pooled analysis of KRAS wt patients from the previous ACT study was performed.

RESULTS

We included 233 patients. Median age was 64 years, 62% male, 68% ECOG 0, 52% with primary tumor in situ. A total of 138 patients started mt after randomization. PFSr was 64.7% versus 63.6% in wt-B versus wt-BE, P = 1.000; and 75% versus 66.7% in mut-B versus mut-C, P = 0.579, with no significant difference in median PFS and overall survival (OS). In the pooled cohort, median PFS was 3.7 months in wt-B (N = 64) and 5.7 months in wt-BE (N = 62) (hazard ratios 1.03, 95% confidence interval 0.70-1.50, P = 0.867). The frequency of any grade 3/4 toxicities during mt was: 28%/58%/18%/15% (wt-B/wt-BE/mut-B/mut-C).

CONCLUSIONS

Addition of erlo to bev as mt in KRAS wt mCRC did not significantly improve PFS or OS, but it did increase toxicity. KRAS status does not seem to influence the outcome of treatment with erlotinib. Metronomic cap warrants further investigation in mt strategies, given our explorative results.

CLINICALTRIALSGOV

NCT01229813.

Maintenance strategies after first-line oxaliplatin plus fluoropyrimidine plus bevacizumab for patients with metastatic colorectal cancer (AIO 0207): a randomised, non-inferiority, open-label, phase 3 trial

BACKGROUND

The definition of a best maintenance strategy following combination chemotherapy plus bevacizumab in metastatic colorectal cancer is unclear. We investigated whether no continuation of therapy or bevacizumab alone are non-inferior to fluoropyrimidine plus bevacizumab, following induction treatment with a fluoropyrimidine plus oxaliplatin plus bevacizumab.

METHODS

In this open-label, non-inferiority, randomised phase 3 trial, we included patients aged 18 years or older with histologically confirmed, previously untreated metastatic colorectal cancer, Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, adequate bone marrow, liver, and renal function, no pre-existing neuropathy greater than grade 1, and measurable disease, from 55 hospitals and 51 private practices in Germany. After 24 weeks of induction therapy with either fluorouracil plus leucovorin plus oxaliplatin or capecitabine plus oxaliplatin, both with bevacizumab, patients without disease progression were randomly assigned centrally by fax (1:1:1) to standard maintenance treatment with a fluoropyrimidine plus bevacizumab, bevacizumab alone, or no treatment. Both patients and investigators were aware of treatment assignment. Stratification criteria were response status, termination of oxaliplatin, previous adjuvant treatment with oxaliplatin, and ECOG performance status. At first progression, re-induction with all drugs of the induction treatment was a planned part of the protocol. Time to failure of strategy was the primary endpoint, defined as time from randomisation to second progression after maintenance (and if applicable re-induction), death, or initiation of further treatment including a new drug. Time to failure of strategy was equivalent to time to first progression for patients who did not receive re-induction (for any reason). The boundary for assessment of non-inferiority was upper limit of the one-sided 98·8% CI 1·43. Analyses were done by intention to treat. The study has completed recruitment, but follow-up of participants is ongoing. The trial is registered with ClinicalTrials.gov, number NCT00973609.

FINDINGS

Between Sept 17, 2009, and Feb 21, 2013, 837 patients were enrolled and 472 randomised; 158 were randomly assigned to receive fluoropyrimidine plus bevacizumab, 156 to receive bevacizumab monotherapy, and 158 to receive no treatment. Median follow-up from randomisation is 17·0 months (IQR 9·5-25·4). Median time to failure of strategy was 6·9 months (95% CI 6·1-8·5) for the fluoropyrimidine plus bevacizumab group, 6·1 months (5·3-7·4) for the bevacizumab alone group, and 6·4 months (4·8-7·6) for the no treatment group. Bevacizumab alone was non-inferior to standard fluoropyrimidine plus bevacizumab (hazard ratio [HR] 1·08 [95% CI 0·85-1·37]; p=0·53; upper limit of the one-sided 99·8% CI 1·42), whereas no treatment was not (HR 1·26 [0·99-1·60]; p=0·056; upper limit of the one-sided 99·8% CI 1·65). The protocol-defined re-induction after first progression was rarely done (30 [19%] patients in the fluoropyrimidine plus bevacizumab group, 67 [43%] in the bevacizumab monotherapy group, and 73 [46%] in the no treatment group. The most common grade 3 adverse event was sensory neuropathy (21 [13%] of 158 patients in the fluoropyrimidine plus bevacizumab group, 22 [14%] of 156 patients in the bevacizumab alone group, and 12 [8%] of 158 patients in the no treatment group).

INTERPRETATION

Although non-inferiority for bevacizumab alone was demonstrated for the primary endpoint, maintenance treatment with a fluoropyrimidine plus bevacizumab may be the preferable option for patients following an induction treatment with a fluoropyrimidine, oxaliplatin, and bevacizumab, as it allows the planned discontinuation of the initial combination without compromising time with controlled disease. Only a few patients were exposed to re-induction treatment, thus deeming the primary endpoint time to failure of strategy non-informative and clinically irrelevant. Progression-free survival and overall survival should be considered primary endpoints in future trials exploring maintenance strategies.

Emerging drugs in refractory colorectal cancer

Colorectal cancer is the third leading cause of cancer-related deaths in the western world. Despite therapeutic advances, the prognosis of metastatic colorectal cancer patients remains poor due to intrinsic or acquired tumor drug resistance. The main mechanisms of tumor drug resistance are represented by genetic and epigenetic alterations. This leads to tumor refractoriness during treatment or disease progression following response to first-line therapy. Strategies to combat chemorefractory tumors involve the development of selective inhibitors of drug-resistant phenotypes, the epigenetic resensitization of drug-resistant cancer cells and new cytotoxic drugs devoid of cross resistance with first-line cytotoxics. The use of drug combination regimens may also increase treatment efficacy, and the exploitation of specific phenomena such as oncogenic and nononcogenic addiction or synthetic lethality represents another potential approach in combating tumor drug resistance. Clinical trials based on such strategies in mCRC patients whose tumors progressed following first-line chemotherapy are discussed herein.

Maintenance treatment with capecitabine and bevacizumab in metastatic colorectal cancer (CAIRO3): a phase 3 randomised controlled trial of the Dutch Colorectal Cancer Group

BACKGROUND

The optimum duration of first-line treatment with chemotherapy in combination with bevacizumab in patients with metastatic colorectal cancer is unknown. The CAIRO3 study was designed to determine the efficacy of maintenance treatment with capecitabine plus bevacizumab versus observation.

METHODS

In this open-label, phase 3, randomised controlled trial, we recruited patients in 64 hospitals in the Netherlands. We included patients older than 18 years with previously untreated metastatic colorectal cancer, with stable disease or better after induction treatment with six 3-weekly cycles of capecitabine, oxaliplatin, and bevacizumab (CAPOX-B), WHO performance status of 0 or 1, and adequate bone marrow, liver, and renal function. Patients were randomly assigned (1:1) to either maintenance treatment with capecitabine and bevacizumab (maintenance group) or observation (observation group). Randomisation was done centrally by minimisation, with stratification according to previous adjuvant chemotherapy, response to induction treatment, WHO performance status, serum lactate dehydrogenase concentration, and treatment centre. Both patients and investigators were aware of treatment assignment. We assessed disease status every 9 weeks. On first progression (defined as PFS1), patients in both groups were to receive the induction regimen of CAPOX-B until second progression (PFS2), which was the study's primary endpoint. All endpoints were calculated from the time of randomisation. Analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00442637.

FINDINGS

Between May 30, 2007, and Oct 15, 2012, we randomly assigned 558 patients to either the maintenance group (n=279) or the observation group (n=279). Median follow-up was 48 months (IQR 36-57). The primary endpoint of median PFS2 was significantly improved in patients on maintenance treatment, and was 8·5 months in the observation group and 11·7 months in the maintenance group (HR 0·67, 95% CI 0·56-0·81, p<0·0001). This difference remained significant when any treatment after PFS1 was considered. Maintenance treatment was well tolerated, although the incidence of hand-foot syndrome was increased (64 [23%] patients with hand-foot skin reaction during maintenance). The global quality of life did not deteriorate during maintenance treatment and was clinically not different between treatment groups.

INTERPRETATION

Maintenance treatment with capecitabine plus bevacizumab after six cycles of CAPOX-B in patients with metastatic colorectal cancer is effective and does not compromise quality of life.

FUNDING

Dutch Colorectal Cancer Group (DCCG). The DCCG received financial support for the study from the Commissie Klinische Studies (CKS) of the Dutch Cancer Foundation (KWF), Roche, and Sanofi-Aventis.

Therapeutic strategy in unresectable metastatic colorectal cancer: an updated review

Systemic therapy is the standard care for patients with unresectable advanced colorectal cancer (CRC), but salvage surgery of metastatic disease should be considered in the case of adequate tumor shrinkage. Several drugs and combinations are now available for use in treating patients with advanced CRC, but the optimal sequence of therapy remains unknown. Moreover, the administration of antitumor therapy can be modulated by periods of maintenance or treatment breaks rather than delivered as full therapy until disease progression or unacceptable toxicity, followed by reintroduction of prior full therapy when required, before switching to other drugs. Consequently, randomized strategy trials are needed to define the optimal treatment sequences. Molecular testing for Kirsten rat sarcoma viral oncogene homolog (KRAS) and neuroblastoma RAS viral oncogene homolog (NRAS) is mandatory but not sufficient to select appropriate patients for epidermal growth factor receptor (EGFR) monoclonal antibody (MoAb) therapy.

In vitro anti-angiogenic effects of Hemidesmus indicus in hypoxic and normoxic conditions

ETHNOPHARMACOLOGICAL RELEVANCE

The decoction of the roots of Hemidesmus indicus is widely used in the Indian traditional medicine for many purposes and poly-herbal preparations containing Hemidesmus are often used by traditional medical practitioners for the treatment of cancer. In the context of anticancer pharmacology, anti-angiogenic therapy has become an effective strategy for inhibiting new vessel formation and contrast tumor growth. These considerations are supported by the evidence that most tumors originate in hypoxic conditions and limitation of oxygen diffusion stimulates the formation of tumor abnormal microvasculature. Aim of this study was to evaluate the in vitro anti-angiogenic potential of Hemidesmus indicus (0.31-0.93 mg/mL) on human umbilical vein endothelial cells and delineate the main molecular mechanisms involved in its anti-angiogenic activity both in normoxia and hypoxia.

MATERIALS AND METHODS

The decoction of Hemidesmus indicus was subjected to an extensive HPLC phytochemical characterization. Its in vitro anti-angiogenic potential was investigated in normoxia and hypoxia. Cell proliferation, apoptosis induction, and inhibition of endothelial cell migration and invasion were analyzed by flow cytometry. The endothelial tube formation assay was evaluated in matrix gel. The capillary tube branch points formed were counted using a Motic AE21 microscope and a VisiCam videocamera. The regulation of key factors of the neovascularization process such as VEGF, HIF-1α and VEGFR-2 was explored at mRNA and protein level by real time PCR and flow cytometry, respectively.

RESULTS

Treatment with Hemidesmus resulted in a significant inhibition of cell proliferation and tube formation in both normoxia and hypoxia. Hemidesmus differently regulated multiple molecular targets related to angiogenesis according to oxygen availability. In normoxia, the inhibition of VEGF was the main responsible for its anti-angiogenic effect; the angiogenesis inhibition induced in hypoxia was regulated by a more complex mechanism involving firstly HIF-1α inhibition, and then VEGF and VEGFR-2 down-regulation. Additionally, the inhibition of endothelial cell migration and invasion by Hemidesmus was more pronounced in normoxia than in hypoxia, possibly due to the physiological enhanced induction of invasion characteristic of hypoxia.

CONCLUSIONS

Our results indicate that Hemidesmus might represent a promising therapeutic strategy for diseases in which the inhibition of angiogenesis could be beneficial, such as cancer. The antiangiogenic activity of Hemidesmus is based on multiple interactions with critical steps in the angiogenic cascade. VEGF expression stimulated by HIF-1α as well as endothelial cell migration and differentiation represent important targets of Hemidesmus action and might contribute to its cancer therapeutic efficacy that is presently emerging and offer a scientific basis for its use in traditional medicine.