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

Tumor Sidedness and Enriched Gene Groups for Efficacy of First-line Cetuximab Treatment in Metastatic Colorectal Cancer

Molecular differences in tumor locations may contribute to the sidedness-specific response to cetuximab in metastatic colorectal cancer (mCRC). We investigated genes associated with the response to cetuximab treatment depending on tumor sidedness. Our study included 77 patients with mCRC (13/63, right/left) with KRAS exon 2 wild-type tumors from phase II trials of first-line therapy with cetuximab. Expression levels of 2,551 genes were measured in tissue samples by HTG EdgeSeq Oncology Biomarker Panel. Univariate Cox regression analysis using log2 values of counts per million (CPM) was conducted in each sidedness to assess associations with clinical outcomes, and to define the optimal cut-off point for clinically significant genes. In addition, a gene set enrichment analysis (GSEA) was performed to identify significant gene pathways in each sidedness. Sixty-nine patients were assessable for gene expression data. Overexpression of BECN1 [log2(CPM) ≥ 6.8] was associated with favorable survival, regardless of tumor sidedness. High expression of NOTCH1 [log2(CPM) ≥ 7.5] predicted significantly longer progression-free survival (PFS; median 14.7 vs. 11.1 months, HR 0.43, P = 0.01) and overall survival (OS; median 42.8 vs. 26.5 months, HR 0.35, P = 0.01) in left side but not in right side. The GSEA showed that regulation of DNA replication gene set correlated with favorable survival in the left, whereas the subcellular component and leukocyte migration gene sets were associated with good survival in the right. In conclusion, genes contributing to the efficacy of cetuximab treatment may differ according to the sidedness in mCRC. NOTCH1 may potentially discriminate favorable responders to cetuximab in patients with left-sided tumors.

Capecitabine Versus Continuous Infusion Fluorouracil for the Treatment of Advanced or Metastatic Colorectal Cancer: a Meta-analysis

OPINION STATEMENT

Nowadays, systemic chemotherapy with intravenous (IV) 5-fluorouracil (5-FU) remains the most commonly prescribed treatment for metastatic colorectal cancers (CRC), in combination with other cytotoxic drugs. 5-FU can be administered through a bolus injection or continuous infusion (cIV), with the latter becoming the preferred administration method and standard of care in recent years. Oral fluoropyrimidines were developed to overcome challenges associated with the IV administration of 5-FU, among which capecitabine has become the most widely used one. However, although capecitabine and other oral fluoropyrimidine-based regimens are more convenient to administer, their efficacy and safety in comparison with IV 5-FU are not well understood. Results from recent randomized controlled trials, observational studies, and meta-analyses have been inconsistent. Safety, in particular, remains controversial. Our review, a first comprehensive meta-analysis comparing the efficacy and safety of cIV 5-FU with capecitabine, the two most widely used fluorouracil modalities in CRC, showed that cIV 5-FU-based regimens are associated with greater response rates compared with capecitabine-based regimens, with no difference in progression-free survival, time to treatment failure, overall survival, or disease-free survival between the two. Furthermore, cIV 5-FU-based regimens showed an improved safety profile compared with capecitabine-based regimens. Our findings suggest that cIV 5-FU remains a more effective and safer modality of fluorouracil administration than capecitabine, thus providing supporting evidence to guide clinical practice in the management of colorectal cancer.

Colorectal Cancer: Why Does Side Matter?

Colorectal cancer (CRC) is a heterogeneous disease, and the search for clinical and molecular prognostic and predictive factors is thus necessary to better tailor each individual patient's management. Primary tumor location (PTL) seems to act as a master prognostic factor pooling different clinical, pathological, and molecular poor prognostic factors. In fact, right-sided (RS) CRC patients are more frequently female and elderly with microsatellite unstable, BRAF mutated, CpG island methylator phenotype (CIMP)-high, poorly differentiated tumors, compared to left-sided (LS) CRC patients. PTL does not seem to clearly influence disease-free survival (DFS) in localised colon cancer even though the opposite prognostic value of RS tumors on DFS depending on RAS/BRAF mutational status has been recently suggested in these patients. In metastatic CRC (mCRC), the poor prognosis associated with RS tumors is confirmed in the most recent publications in the era of double and triple chemotherapeutic regimens and targeted agents. Concerning the predictive value of PTL, in patients with RAS wild-type mCRC in the first-line setting, anti-epidermal growth factor receptor (EGFR) therapy combined with chemotherapy appears to be more effective than bevacizumab in LS CRC, while patients with RS CRC benefit less from anti-EGFR therapy, and intensive chemotherapy plus bevacizumab may be more appropriate but EGFR antibodies remain an option if objective response is needed. Due to the limitation of the current data (unplanned and retrospective analyses), these conclusions must be interpreted with caution. Clinical trials in RS CRC may be of interest to clarify what is the best treatment strategy in these patients.

Third- or Later-line Therapy for Metastatic Colorectal Cancer: Reviewing Best Practice

An increasing number of patients with metastatic colorectal cancer (mCRC) are able to receive 3 or more lines of therapy. Treatments in this setting can include regorafenib (an oral multikinase inhibitor), trifluridine/tipiracil hydrochloride (TAS-102), antibodies that target epidermal growth factor receptor for patients with RAS wild-type tumors (if no prior exposure), and, where approved, anti-programmed cell death protein 1 inhibitors for patients with microsatellite instability-high mCRC. Although guidelines describe the available treatment options, few insights are provided to guide selection and sequencing. In this article, we share expert opinion from diverse geographic regions, to offer guidance for best practice when selecting and managing third-line treatment for mCRC. Various factors, including performance status, age, and tumor sidedness, can be used to guide treatment selection. Biomarkers, such as RAS, BRAF, and microsatellite instability, can be useful for treatment stratification. Management of adverse events, to maintain quality of life, is a key consideration and is crucial to best practice in this setting. Common toxicities associated with third-line treatments are hand-foot skin reaction, fatigue, diarrhea, and cytopenias. Patients who receive third-line and later-line treatments should be monitored for these events, especially during the first 2 cycles. Dose modifications can also be used to manage toxicities and to minimize the effect on quality of life, while maximizing treatment benefit. Clinical trials of emerging agents, new treatment combinations, and novel therapies continue the efforts to improve outcomes for patients with mCRC. Sharing expert opinions on best practice for treatment selection and management can ultimately improve outcomes for patients with mCRC.

Clinical Validation of Newly Developed Multiplex Kit Using Luminex xMAP Technology for Detecting Simultaneous RAS and BRAF Mutations in Colorectal Cancer: Results of the RASKET-B Study

Detection of RAS and BRAF mutations is essential to determine the optimal treatment strategy for metastatic colorectal cancer (CRC). We prospectively evaluated the MEBGEN RASKET-B KIT (RASKET-B), a novel multiplex kit, simultaneously detecting 48 types of RAS mutations and the BRAF V600E mutation using Luminex xMAP technology. The aim was to obtain market approval for RASKET-B as an in vitro diagnostic (IVD) option in Japan. Genomic DNA was extracted from 302 formalin-fixed paraffin-embedded tissues obtained from CRC patients. The primary endpoints were the concordance rate (CR) between the results from RASKET-B and the previously approved IVD kit (RASKET) for RAS mutations, and CR between the results from RASKET-B and direct sequencing (DS) for BRAF mutations. The secondary endpoints included the CR between RASKET-B and DS for RAS mutations and between RASKET-B and the pyrosequencing (PYRO) for the BRAF V600E mutation. Among the 302 samples, 142 RAS mutations (47%) and 18 BRAF V600E mutations (6.0%) were detected by RASKET-B. All mutations detected in the recruited patients were mutually exclusive. Both RAS and BRAF mutation rates were statistically higher in right-sided than left-sided CRC. The CR between RASKET-B and RASKET for RAS gene and RASKET-B and DS for BRAF V600E mutation was 100% for both (95% CI: 99%-100%). The results from RASKET-B were also highly concordant with DS for RAS (97.4%) and with PYRO for the BRAF (V600E) gene (99.7%). RASKET-B thus provides rapid, precise, and simultaneous detection of RAS and BRAF mutations in CRC.

Clinicopathological differences and survival outcomes with first-line therapy in patients with left-sided colon cancer and rectal cancer: Pooled analysis of 2879 patients from AGITG (MAX), COIN, FOCUS2, OPUS, CRYSTAL and COIN-B trials in the ARCAD database

PURPOSE

Patients with left-sided colon tumours have better survival and respond differently to biologics compared with patients with right-sided tumours. Left-sided colon tumours and rectal cancers are often grouped together. Herein, we examined the clinicopathological differences and outcomes between left-sided colon and rectal cancers.

PATIENTS AND METHODS

Data from 2879 metastatic colorectal cancer patients enrolled on six first-line clinical trials during 2004-2010 were pooled. Patients were included if the primary tumour origin was clearly defined. Progression-free survival (PFS) and overall survival (OS) were compared in the two groups after adjusting for patient and tumour characteristics, metastatic sites and the first-line regimen.

RESULTS

In total, 1374 patients with metastatic left-sided colon cancer and 1505 patients with metastatic rectal cancers were evaluated. Left-sided colon cancer patients were more likely to be female (40.1% versus 32.6%; P < 0.0001) and older (31.0% ≥ 70 years versus 25.8%; P = 0.0033) compared with rectal cancers patients. Patients with left-sided colon cancer had higher rates of liver metastases (80.9% versus 72.3%, P < 0.0001) but lower rates of lung metastases (34.2% versus 53.8%, P < 0.0001). KRAS mutations were slightly less frequent among left-sided tumours (34.8% versus 40.5%; P = 0.0103). Patients with left-sided tumours had approximately similar PFS (median 7.4 versus 6.9 months; hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.87-1.03; P = 0.1998) and OS (median 17.4 versus 16.6 months; HR 0.99, 95% CI 0.91-1.07; P = 0.7597) compared with rectal cancer patients.

CONCLUSION

The site of tumour origin within the left side was not prognostic of outcomes. Moreover, neither bevacizumab nor cetuximab impacted, differently, the findings of the comparisons in outcomes between patients with left-sided colon tumours or rectal cancers.

Phase Ib study of irinotecan and ramucirumab for advanced gastric cancer previously treated with fluoropyrimidine with/without platinum and taxane

PURPOSE

Optimal salvage chemotherapy for patients with treated advanced/metastatic gastric cancer (AGC) is unknown. Irinotecan is commonly used in Japan. Ramucirumab, a human IgG-1 monoclonal antibody targeting the extracellular domain of VEGF receptor 2, is the first molecularly targeted agent proven to be effective in second-line therapy for AGC in combination with chemotherapy. We sought to determine the maximum tolerated dose (MTD) and recommended dose (RD) of ramucirumab plus irinotecan for AGC previously treated with fluoropyrimidine with/without platinum and taxane.

METHODS

Patients received systemic chemotherapy with ramucirumab (8 mg/kg) and irinotecan on day 1, repeated every 2 weeks. A decrease in irinotecan dose was planned from start level 1 (irinotecan 150 mg/m2). This trial was registered with the University Hospital Medical Network (UMIN no. 000018606).

RESULTS

Six patients were enrolled from August 2015 to September 2017. No dose-limiting toxicity (DLT) was observed, and the maximum tolerated dose (MTD) was not reached at level 1. Irinotecan 150 mg/m2 in combination with ramucirumab 8 mg/kg was administered with acceptable toxicity, and all patients were treated at these doses. No treatment-related deaths were observed. Adverse events of Grade 3/4 were neutropenia (17%), anemia (17%) and hypertension (17%). Patients were evaluated using the RECIST criteria, and response rate and disease control rate were 17% and 83%, respectively.

CONCLUSIONS

Salvage chemotherapy with irinotecan plus ramucirumab was well-tolerated by patients previously treated for AGC. RD was defined as irinotecan 150 mg/m2 in combination with ramucirumab 8 mg/kg.

Recent advances in understanding colorectal cancer

The achievements in the treatment of metastatic colorectal cancer during recent years are based on a better understanding of the disease and individualized regimen planning. In adjuvant treatment, the highly important IDEA (International Duration Evaluation of Adjuvant Chemotherapy) study has shown that treatment duration can safely be reduced in selected patient populations. In patients with pN1 and pT1-pT3 tumors, 3 months of treatment with 5-fluorouracil and oxaliplatin is comparable with respect to 3-year survival rate to 6 months of treatment. For patients with N2 tumors, 6 months of treatment should stay the standard of care. The limitation of the duration of the adjuvant treatment is significantly reducing the chemotherapy-induced morbidity. New studies will explore the use of immune-checkpoint inhibitors in the adjuvant setting in microsatellite-instable (MSI) tumors. In metastatic disease, next to the required molecular testing for RAS and BRAF mutations, MSI testing is recommended. In the rare group of patients with a MSI tumor, immune-checkpoint inhibition is changing the course of the disease dramatically. Therefore, it is important to identify those patients early. For the RAS-mutant cases, no new and targeted treatment options have been identified yet. An optimal treatment strategy for those patients is urgently needed. RAS wild-type patients with tumors derived from the left side of the colon (splenic flexure to rectum) should be treated in first line with epithelial growth factor receptor (EGFR) antibodies. This selection by a molecular and a clinical marker increased the benefit derived by EGFR antibodies dramatically and defined the most effective treatment option for those patients. New selection criteria based on gene expression, methylation, and other molecular changes are explored and will further influence our therapeutic strategies in the future.

Skin Disorders and Primary Tumor Location as Prognostic Factors in Patients with Metastatic Colorectal Cancer Treated with Cetuximab and Chemotherapy

Background:

Cetuximab-induced skin disorder is common in colorectal cancer (CRC), and is known to affect prolonged overall survival (OS). Patients with left-sided CRC survive longer than those with right-sided CRC, among those treated with combination cetuximab and chemotherapy. However, no study has evaluated patient prognosis in terms of OS and progression-free survival (PFS) in relation to both tumor location and skin disorder. This study aimed to determine the incidence of skin disorder according to tumor location and analyze the relationship of tumor location and skin disorder with OS.

Methods:

Patients with metastatic colorectal cancer (mCRC) treated with standard chemotherapy and cetuximab as first-line therapy were included. Differences in the incidence of skin disorders due to the location of the primary tumors were compared in the same patient. The OS and PFS in relation to the location of the primary tumors and presence or absence of skin disorder were also compared.

Results:

Total frequency of each skin disorder as rash acneiform, paronychia, and dry skin in patients with left- and right-sided mCRC was 70%, 70%, and 43% and 27%, 36%, and 27%, respectively. The median OS was 8.9 months for mCRC on the left-sided without skin disorder and 56.3 months for mCRC on the left-sided with skin disorder. In comparison, the median OS was 10.4 months for mCRC on the right-sided without skin disorder and 11.3 months for mCRC on the right-sided with skin disease (left-sided with skin disorder versus other three group; P<0.001).

Conclusions:

Primary tumor location and the presence of skin disorder are important factors in patients with mCRC who receive cetuximab. In particular, our results show the new fact that the left-sided and right-sided mCRC survival time were comparable if there is no skin disorder caused by cetuximab.

Rationale and design of the TRUSTY study: a randomised, multicentre, open-label phase II/III study of trifluridine/tipiracil plus bevacizumab versus irinotecan, fluoropyrimidine plus bevacizumab as second-line treatment in patients with metastatic colorectal cancer progressive during or following first-line oxaliplatin-based chemotherapy

Background

Trifluridine/tipiracil is an oral agent approved for the treatment of patients with metastatic colorectal cancer (mCRC). Trifluridine is an antineoplastic thymidine analogue, and tipiracil improves its bioavailability. A phase I/II C-TASK FORCE study of trifluridine/tipiracil plus bevacizumab for patients with refractory mCRC demonstrated promising efficacy results with mild toxicity profile. It is important that quality of life be preserved in patients with mCRC without compromising their prognosis. Here, we outline the TRiflUridine/tipiracil in Second-line sTudY phase II/III study (JapicCTI-173618), designed to demonstrate non-inferiority in overall survival of trifluridine/tipiracil plus bevacizumab compared with irinotecan, fluoropyrimidine and bevacizumab combination regimens as second-line treatment in patients with mCRC.

Patients and methods

Eligible patients have confirmed unresectable advanced or recurrent colorectal adenocarcinoma and have failed to respond to first-line oxaliplatin-based chemotherapy. A total of 524 patients are to be randomly assigned (1:1 ratio) to trifluridine/tipiracil plus bevacizumab or irinotecan, fluoropyrimidine and bevacizumab and stratified according to RAS status (wild type vs mutant). The primary endpoint of the phase II part is disease control rate with trifluridine/tipiracil plus bevacizumab therapy. Secondary endpoints are response rate and safety with trifluridine/tipiracil plus bevacizumab therapy. In the phase III part, the primary endpoint is overall survival, and secondary endpoints include quality of life, progression-free survival, response rate, disease control rate, safety, time to treatment failure, time to post-study treatment failure and the proportion of patients receiving post-study treatment. The first patient was enrolled in October 2017 and the study is anticipated to be completed in 2022.

Clinical trial registration

JapicCTI-173618 (JapicCTI).

Trifluridine/tipiracil: an emerging strategy for the management of gastrointestinal cancers

Fluoropyrimidines are currently the backbone of treatment for gastrointestinal (GI) cancers but development of resistance to these agents remains a major problem. Trifluridine/tipiracil is an oral chemotherapeutic agent recently approved for third-line treatment of chemorefractory metastatic colorectal cancer. This article reviews the clinical value of trifluridine/tipiracil as a monotherapy, including recent trials in GI cancers, and the potential benefit of combining it with other agents in patients with GI cancers, including the preclinical rationale for combination therapy and recently completed and ongoing clinical trials. Data gathered so far suggest that trifluridine/tipiracil has the potential to form the chemotherapeutic backbone in the continuum of care for GI cancers in the future.

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.

Japanese Society of Medical Oncology Clinical Guidelines: Molecular Testing for Colorectal Cancer Treatment, Third Edition

The Japanese Society of Medical Oncology (JSMO) previously published 2 editions of the clinical guidelines: "Japanese guidelines for testing of KRAS gene mutation in colorectal cancer" in 2008 and "Japanese Society of Medical Oncology Clinical Guidelines: RAS (KRAS/NRAS) mutation testing in colorectal cancer patients" in 2014. These guidelines have contributed to the proper use of KRAS and RAS mutation testing, respectively. Recently, clinical utility, particularly for colorectal cancer (CRC) patients with BRAF V600E mutation or DNA mismatch-repair (MMR) deficiency, has been established. Therefore, the guideline members decided these genetic alterations should also be involved. The aim of this revision is to properly carry out testing for BRAF V600E mutation and MMR deficiency in addition to RAS mutation. The revised guidelines include the basic requirements for testing for these genetic alterations based on recent scientific evidence. Furthermore, because clinical utility of comprehensive genetic testing using next-generation sequencing and somatic gene testing of analyzing circulating tumor DNA has increasingly evolved with recent advancements in testing technology, we noted the current situation and prospects for these testing technologies and their clinical implementation in the revised guidelines.

Prognostic and Predictive Value of HER2 Amplification in Patients With Metastatic Colorectal Cancer

PURPOSE

To evaluate a prognostic and predictive value of HER2 amplification in patients with metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Patients with mCRC who underwent surgical resection of the primary tumor and who received best supportive care with or without palliative chemotherapy between 2005 and 2015 were included. HER2 immunohistochemistry was performed using formalin-fixed, paraffin-embedded primary tumor specimens. HER2 amplification was confirmed by fluorescence in-situ hybridization. The RAS and BRAF^V600E mutations were centrally assessed using a PCR-based method. Patients were divided into 4 subgroups: R (RAS mutant), B (BRAF^V600E mutant), H (wild-type RAS/BRAF with HER2 amplification), and W (wild-type RAS/BRAF without HER2 amplification). Overall survival (OS) and progression-free survival of anti-epidermal growth factor receptor (EGFR) therapy were assessed.

RESULTS

Among 370 eligible patients, data of 359 were successfully analyzed. Fifteen tumors harbored HER2 amplifications, including 4 tumors with concomitant RAS mutation (group R). The number of patients in groups R, B, H, and W was 204, 13, 11, and 131, respectively. The median OS was 27.4 months, and the median follow-up time was 63.2 months. The median OS for groups R, B, H, and W was 24.0, 14.2, 19.9, and 39.1 months, respectively. The number of patients who received anti-EGFR therapy in groups R, B, H, and W was 17, 4, 5, and 49, respectively. Progression-free survival of anti-EGFR therapy was significantly shorter in groups R, B, and H than in group W.

CONCLUSION

HER2 amplification was predictive of anti-EGFR therapy response and appeared to be prognostic in mCRC patients.

Consensus on management of metastatic colorectal cancer in Central America and the Caribbean: San José, Costa Rica, August 2016

Colorectal cancer (CRC) is the third most common cancer in men and the second most common in women worldwide. In Latin America and the Caribbean, it has a mortality of 56%. The median overall survival for patients with metastatic colorectal cancer (mCRC) is currently estimated as ~30 months, which has substantially improved through strategic changes in treatment and in the management of patients. As opposed to other metastatic cancers where first-line regimens are often determined, mCRC requires special attention because there is controversy in the possible combinations of the available drugs and the different periods of duration for each patient. Each combination must seek to be effective and to generate the minimum adverse effects as possible. Instead of giving the first-line regimen until the tumour progresses, treatment is often individualised. Furthermore, up to 60% of colorectal tumours are considered non-mutated or wild-type CRC. Not harbouring mutations in the RAS family of genes or mutations in the signalling pathways of the epidermal growth factor receptor causes a null response to anti-epidermal growth factor receptor antibody therapy, which implies even more complex considerations regarding its management. The primary objective of this consensus is to address the main scenarios of mCRC in order to warrant the most appropriate therapeutic intervention for these patients in the Central American and the Caribbean (CAC) region. This can lead to better clinical outcomes as well as quality of life for palliative patients. This document includes the formal expert consensus recommendations for scenarios of mutated and non-mutated mCRC, including synchronous or metachronous disease, management of mCRC with liver and lung metastasis, resectable, potentially resectable or non-resectable tumours and local in the CAC context.