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

Optimum patient selection for irinotecan-containing regimens in metastatic colorectal cancer: Literature review and lessons from clinical practice

Metastatic colorectal cancer (mCRC) accounts for over 20% of CRC cases and is associated with a poor prognosis. Irinotecan is an important first- and second-line chemotherapy option for mCRC. In this review, we summarize the clinical efficacy and safety of irinotecan-based regimens for the treatment of mCRC and discuss various tumor- and patient-related factors that affect the clinical response, survival, and toxicity associated with these regimens. Uridine diphosphate glucuronosyltransferase (UGT) gene polymorphisms such as UGT1A1*28/*6, age, performance status, serum lactate dehydrogenase levels, and bilirubin levels could be important considerations for predicting outcomes and tolerability with irinotecan-based regimens. The role of tumor location; chemotherapy backbone; and emerging evidence on the presence of microsatellite instability-high status, consensus molecular subtype 4 tumors, and signet-ring morphology in predicting response to irinotecan-based therapy have also been highlighted. Careful consideration of these factors will help guide clinicians in optimizing the selection of mCRC patients for irinotecan-based treatment.

Postoperative chemotherapy is associated with prognosis of stage IV colorectal cancer treated with preoperative chemotherapy/chemoradiotherapy and curative resection

PURPOSE

Advances in systemic chemotherapy have increased the resectability in colorectal cancer (CRC) associated with metastases even if it was initially unresectable. However, what determines the prognosis of stage IV CRC patients treated by preoperative therapy and surgery remains unclear. We attempted to identify prognostic factors in such CRC patients.

METHODS

We reviewed stage IV CRC patients who underwent curative resection between December 2007 and May 2019. The patients who underwent conversion chemotherapy for initially unresectable disease and those who received neoadjuvant chemotherapy (NAC) for resectable synchronous metastases or neoadjuvant chemoradiotherapy (NACRT) for advanced lower rectal cancer with resectable metastases were included. Recurrence-free survival (RFS) and overall survival (OS) were examined by multivariate analyses using Cox proportional hazard models. The RFS and OS curves were analyzed according to postoperative adjuvant chemotherapy (AC).

RESULTS

Among 70 patients who underwent curative surgery (34 men, mean age: 60 years old), 33 had initially unresectable disease, 23 received NAC, and 14 NACRT. By multivariate analyses, AC was an independent predictor for improved RFS and OS (hazard ratio = 0.29, p = 0.0002, and hazard ratio = 0.37, p = 0.025). Patients treated with AC showed improved RFS and OS than those without AC (2-year RFS rate = 30% vs 19%, p = 0.031, and 3-year OS rate = 87% vs 67%, p = 0.045).

CONCLUSION

Because of its association with improved prognosis, AC should be considered for stage IV CRC patients after curative resection regardless of initial resectability status and preoperative therapy.

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

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

Biomarker-guided therapy for colorectal cancer: strength in complexity

The number of molecularly stratified treatment options available to patients with colorectal cancer (CRC) is increasing, with a parallel rise in the use of biomarkers to guide prognostication and treatment decision-making. The increase in both the number of biomarkers and their use has resulted in a progressively complex situation, evident both from the extensive interactions between biomarkers and from their sometimes complex associations with patient prognosis and treatment benefit. Current and emerging biomarkers also reflect the genomic complexity of CRC, and include a wide range of aberrations such as point mutations, amplifications, fusions and hypermutator phenotypes, in addition to global gene expression subtypes. In this Review, we provide an overview of current and emerging clinically relevant biomarkers and their role in the management of patients with CRC, illustrating the intricacies of biomarker interactions and the growing treatment opportunities created by the availability of comprehensive molecular profiling.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the management of patients with locally-advanced unresectable non-small-cell lung cancer: a KSMO-ESMO initiative endorsed by CSCO, ISMPO, JSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of early and locally-advanced non-small-cell lung cancer (NSCLC) was published in 2017, and covered the diagnosis, staging, management and treatment of both early stage I and II disease and locally-advanced stage III disease. At the ESMO Asia Meeting in November 2018, it was decided by both the ESMO and the Korean Society of Medical Oncology (KSMO) to convene a special face-to-face guidelines meeting in 2019 in Seoul. The aim was to adapt the ESMO 2017 guidelines to take into account potential differences related to ethnicity, cancer biology and standard practices associated with the treatment of locally-advanced, unresectable NSCLC in Asian patients. These guidelines represent the consensus opinions reached by those experts in the treatment of patients with lung cancer who represented the oncology societies of Korea (KSMO), China (CSCO), India (ISMPO), Japan (JSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and it was independent of both local current treatment practices and the treatment availability and reimbursement situations in the individual participating Asian countries.

Overcoming Drug Resistance by Taking Advantage of Physical Principles: Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC)

Theoretical considerations as well as comprehensive preclinical and clinical data suggest that optimizing physical parameters of intraperitoneal drug delivery might help to circumvent initial or acquired resistance of peritoneal metastasis (PM) to chemotherapy. Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is a novel minimally invasive drug delivery system systematically addressing the current limitations of intraperitoneal chemotherapy. The rationale behind PIPAC is: (1) optimizing homogeneity of drug distribution by applying an aerosol rather than a liquid solution; (2) applying increased intraperitoneal hydrostatic pressure to counteract elevated intratumoral interstitial fluid pressure; (3) limiting blood outflow during drug application; (4) steering environmental parameters (temperature, pH, electrostatic charge etc.) in the peritoneal cavity for best tissue target effect. In addition, PIPAC allows repeated application and objective assessment of tumor response by comparing biopsies between chemotherapy cycles. Although incompletely understood, the reasons that allow PIPAC to overcome established chemoresistance are probably linked to local dose intensification. All pharmacological data published so far show a superior therapeutic ratio (tissue concentration/dose applied) of PIPAC vs. systemic administration, of PIPAC vs. intraperitoneal liquid chemotherapy, of PIPAC vs. Hyperthermic Intraperitoneal Chemotherapy (HIPEC) or PIPAC vs. laparoscopic HIPEC. In the initial introduction phase, PIPAC has been used in patients who were quite ill and had already failed multiple treatment regimes, but it may not be limited to that group of patients in the future. Rapid diffusion of PIPAC in clinical practice worldwide supports its potential to become a game changer in the treatment of chemoresistant isolated PM of various origins.

BTK inhibitors synergise with 5-FU to treat drug-resistant TP53-null colon cancers

Colorectal cancer (CRC) is the fourth cause of death from cancer worldwide mainly due to the high incidence of drug-resistance. During a screen for new actionable targets in drug-resistant tumours we recently identified p65BTK - a novel oncogenic isoform of Bruton's tyrosine kinase. Studying three different cohorts of patients here we show that p65BTK expression correlates with histotype and cancer progression. Using drug-resistant TP53-null colon cancer cells as a model we demonstrated that p65BTK silencing or chemical inhibition overcame the 5-fluorouracil resistance of CRC cell lines and patient-derived organoids and significantly reduced the growth of xenografted tumours. Mechanistically, we show that blocking p65BTK in drug-resistant cells abolished a 5-FU-elicited TGFB1 protective response and triggered E2F-dependent apoptosis. Taken together, our data demonstrated that targeting p65BTK restores the apoptotic response to chemotherapy of drug-resistant CRCs and gives a proof-of-concept for suggesting the use of BTK inhibitors in combination with 5-FU as a novel therapeutic approach in CRC patients. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Atypical RAS Mutations in Metastatic Colorectal Cancer

PURPOSE

To describe the clinical and molecular features of metastatic colorectal cancers (mCRCs) bearing uncommon atypical RAS (At-RAS) mutations at codons other than 12, 13, 59, 61, 117, and 146.

MATERIALS AND METHODS

By exploiting five next-generation sequencing sources (Italian collaboration, Memorial Sloan Kettering Cancer Center, Samsung Medical Center, the Biomarker Research for Anti-EGFR Monoclonal Antibodies by Comprehensive Cancer Genomics (BREAC) study, and the Foundation Medicine database), we retrieved 175 At-RAS mutated cases. Molecular data were obtained from 163 samples from Memorial Sloan Kettering Cancer Center and the Foundation Medicine database. Clinical data were available for 27 At-RAS-positive and 467 negative cases from the Italian collaboration, Memorial Sloan Kettering Cancer Center, Samsung Medical Center, and the BREAC study.

RESULTS

At-RAS mutations were identified in 163 (0.9%) of 18,270 mCRCs. Among 133 with evaluable microsatellite instability status, 11 (8%) were microsatellite instability high. POLE exonuclease domain mutations had higher frequency (7%) than expected and were found only in microsatellite-stable tumors with high tumor mutational burden (TMB). Overall, 17% (28 of 163) of At-RAS cases had TMB greater than 20 mutations/Mb. Co-occurring typical RAS/BRAF V600E mutations and NF1 mutations, presumed to cause RAS activation, were found in 30% and 12% of samples, respectively (up to 43% and 50%, respectively, in TMB-high samples). Patients with RAS/BRAF wild-type mCRC achieved a median overall survival (OS) of 42.1 months, whereas those harboring isolated At-RAS, typical RAS, or BRAF V600E mutations showed a median OS of 32.3, 30.0, and 17.9 months, respectively (P < .001). No significant OS difference (P = .240) was found between patients with At-RAS versus typical RAS-mutated mCRC. Only one of six patients evaluable for primary resistance to anti-epidermal growth factor receptors achieved tumor response.

CONCLUSION

At-RAS mutations may be a marker for RAS pathway activation and can be associated with high co-occurrence of POLE exonuclease domain mutations.

Does Tumour Contrast Retention on CT Immediately Post Chemoembolization Predict Tumour Metabolic Response on FDG-PET in Patients with Hepatic Metastases from Colorectal Cancer?

Purpose

The exact mechanism of action of chemoembolization with drug eluting beads loaded with irinotecan (DEBIRI) in colorectal cancer is undetermined. Posttreatment tumour contrast retention often seen on CT immediately post procedure is of indeterminate significance. This study is aimed at assessing if metabolic response on PET-CT can be related to posttreatment tumour contrast retention.

Materials and Methods

In this retrospective study, a total of 17 patients with a total of 55 marker lesions were recruited.

Results

The area of tumour contrast retention can be matched to a hypometabolic area on subsequent PET-CT in over 36 lesions (65.5%). Out of the 55 lesions, a total of 38 marker lesions in 11 patients who also had pre-DEBIRI PET-CT were analyzed for disease response. 10 out of 10 lesions that had a complete response on PET-CT were found to demonstrate contrast retention throughout the tumour. 12 out of 13 (92.3%) tumours that had a partial metabolic response on PET-CT were found to demonstrate contrast uptake in the hypometabolic area only. In the 15 lesions that had progression/no response, 13 (86.6%) demonstrated no relationship between tumour contrast retention and tumour response. There was a significant correlation between contrast retention and disease response (P < 0.001).

Conclusion

Our study showed that PET-CT response can be associated with post embolization contrast retention. The data suggests blood stasis, for which tumour contrast retention is a surrogate marker, is important for the PET-CT metabolic response. The authors propose that tumour contrast retention is an important embolization endpoint in DEBIRI.

Consensus molecular subgroups (CMS) of colorectal cancer (CRC) and first-line efficacy of FOLFIRI plus cetuximab or bevacizumab in the FIRE3 (AIO KRK-0306) trial

BACKGROUND

FIRE-3 compared first-line therapy with FOLFIRI plus either cetuximab or bevacizumab in 592 KRAS exon 2 wild-type metastatic colorectal cancer (mCRC) patients. The consensus molecular subgroups (CMS) are grouping CRC samples according to their gene-signature in four different subtypes. Relevance of CMS for the treatment of mCRC has yet to be defined.

PATIENTS AND METHODS

In this exploratory analysis, patients were grouped according to the previously published tumor CRC-CMSs. Objective response rates (ORR) were compared using chi-square test. Overall survival (OS) and progression-free survival (PFS) times were compared using Kaplan-Meier estimation, log-rank tests. Hazard ratios (HR) were estimated according to the Cox proportional hazard method.

RESULTS

CMS classification could be determined in 438 out of 514 specimens available from the intent-to-treat (ITT) population (n = 592). Frequencies for the remaining 438 samples were as follows: CMS1 (14%), CMS2 (37%), CMS3 (15%), CMS4 (34%). For the 315 RAS wild-type tumors, frequencies were as follows: CMS1 (12%), CMS2 (41%), CMS3 (11%), CMS4 (34%). CMS distribution in right- versus (vs) left-sided primary tumors was as follows: CMS1 (27% versus 11%), CMS2 (28% versus 45%), CMS3 (10% versus 12%), CMS4 (35% versus 32%). Independent of the treatment, CMS was a strong prognostic factor for ORR (P = 0.051), PFS (P < 0.001), and OS (P < 0.001). Within the RAS wild-type population, OS observed in CMS4 significantly favored FOLFIRI cetuximab over FOLFIRI bevacizumab. In CMS3, OS showed a trend in favor of the cetuximab arm, while OS was comparable in CMS1 and CMS2, independent of targeted therapy.

CONCLUSIONS

CMS classification is prognostic for mCRC. Prolonged OS induced by FOLFIRI plus cetuximab versus FOLFIRI plus bevacizumab in the FIRE-3 study appears to be driven by CMS3 and CMS4. CMS classification provides deeper insights into the biology to CRC, but at present time has no direct impact on clinical decision-making.The FIRE-3 (AIO KRK-0306) study had been registered at ClinicalTrials.gov: NCT00433927.

A Phase II Study of Regorafenib With a Lower Starting Dose in Patients With Metastatic Colorectal Cancer: Exposure-Toxicity Analysis of Unbound Regorafenib and Its Active Metabolites (RESET Trial)

BACKGROUND

Regorafenib demonstrated survival benefits as salvage therapy for patients with metastatic colorectal cancer. However, severe toxicities frequently occurred early in the treatment with the standard dose (160 mg/day), resulting in a dose reduction or interruption. To improve the tolerability and maintain sufficient efficacy, we conducted a phase II study of regorafenib with a lower starting dose (120 mg/day).

PATIENTS AND METHODS

Regorafenib was initiated at 120 mg/day, and the dosage was increased to 160 mg/day on day 15 of the first cycle for patients who had met the dose escalation criteria. The primary endpoint was the disease control rate (DCR). The pharmacokinetics of the total and unbound regorafenib and its active metabolites (M2, M5) were assessed.

RESULTS

A total of 70 patients were enrolled from September 2016 to December 2017. Only 6 patients achieved dose escalation to 160 mg on day 15 as planned. For the 68 evaluable patients, the DCR was 32.4% (95% confidence interval, 21.5%-44.8%), which was less than the threshold (30%) of our statistical hypothesis. The serum concentrations of total regorafenib for patients whose dose was escalated to 160 mg/day were significantly lower than those of the patients whose dose was not escalated (median, 3978 vs. 7244 nM; P = .027). The serum unbound concentrations of the sum of regorafenib and the active metabolites correlated significantly with the maximum grade of regorafenib-related symptomatic adverse events in the first cycle (11,138 vs. 19,096 pM; P = .035).

CONCLUSION

Regorafenib with a low starting dose of 120 mg/day did not achieve the expected DCR. A relationship of unbound exposure with toxicity was found.

Predictive And Prognostic Value Of Hepatic Steatosis In Conversion Therapy For Colorectal Liver-limited Metastases: A Propensity Score Matching Analysis

Purpose

To evaluate the role of hepatic steatosis (HS) in patients with synchronous colorectal liver-limited metastases (CLLMs) undergoing conversion therapy.

Patients and methods

From March 2013 to March 2017, a total of 406 patients with initially unresectable CLLMs accepted conversion therapy in multidisciplinary team (MDT). Before the implementation of conversion therapy, all patients underwent CT scan to assess the presence of hepatic steatosis and divided into the HS group (n = 124) and the non-HS group (n = 282). After using propensity score matching (PSM) to eliminate the potential confounding bias of the two groups, the conversion hepatectomy rate and long-term oncological survival in two groups were compared.

Results

After 1:1 PSM, no significant difference was observed at baseline between patients in the HS group (n = 119) and the non-HS group (n = 119). Patients in the HS group had higher conversion hepatectomy rate from MDT evaluation (31.1% vs 18.5%, P = 0.029) and actual hepatectomy rate (30.2% vs 18.5%, P = 0.030), when compared with patients in the non-HS group, respectively. In addition, the HS group achieved better progression-free survival (PFS, P = 0.047) and overall survival (OS, P = 0.035) than that of the non-HS group. Multivariate logistic analysis confirmed that pretreatment HS was an independent predictor for conversion hepatectomy rate (OR, 2.393; 95% CI, 1.463–4.315, P = 0.001), and multivariate Cox analysis revealed that HS was an independent prognostic factor for PFS (HR, 0.493, 95% CI 0.281–0.866, P = 0.014) and OS (HR, 0.559, 95% CI 0.398–0.785, P = 0.001).

Conclusion

For CLLM patients who underwent conversion therapy, hepatic steatosis could be an effective predictor for conversion hepatectomy rate and an independent prognostic factor for PFS and OS.

Response to Anti-EGFR Therapy in Patients with BRAF non-V600-Mutant Metastatic Colorectal Cancer

PURPOSE

While mutations in BRAF in metastatic colorectal cancer (mCRC) most commonly occur at the V600 amino acid, with the advent of next-generation sequencing, non-V600 BRAF mutations are increasingly identified in clinical practice. It is unclear whether these mutants, like BRAF V600E, confer resistance to anti-EGFR therapy.

EXPERIMENTAL DESIGN

We conducted a multicenter pooled analysis of consecutive patients with non-V600 BRAF-mutated mCRCs identified between 2010 and 2017. Non-V600 BRAF mutations were divided into functional classes based on signaling mechanism and kinase activity: activating and RAS-independent (class 2) or kinase-impaired and RAS-dependent (class 3).

RESULTS

Forty patients with oncogenic non-V600 BRAF-mutant mCRC received anti-EGFR antibody treatment [n = 12 (30%) class 2 and n = 28 (70%) class 3]. No significant differences in clinical characteristics were observed by mutation class. In contrast, while only 1 of 12 patients with class 2 BRAF mCRC responded, 14 of 28 patients with class 3 BRAF responded to anti-EGFR therapy (response rate, 8% and 50%, respectively, P = 0.02). Specifically, in first- or second-line, 1 of 6 (17%) patients with class 2 and 7 of 9 (78%) patients with class 3 BRAF mutants responded (P = 0.04). In third- or later-line, none of 6 patients with class 2 and 7 of 19 (37%) patients with class 3 BRAF mutants responded (P = 0.14).

CONCLUSIONS

Response to EGFR antibody treatment in mCRCs with class 2 BRAF mutants is rare, while a large portion of CRCs with class 3 BRAF mutants respond. Patients with colorectal cancer with class 3 BRAF mutations should be considered for anti-EGFR antibody treatment.See related commentary by Fontana and Valeri, p. 6896.

Cancers in Taiwan: Practical insight from epidemiology, treatments, biomarkers, and cost

Cancer is the leading cause of death in Taiwan, and the overall incidence rate has gradually increased. The four most common cancers in Taiwan are colorectal, lung, breast and liver cancers. With the rise in incidence, the clinical use and costs of all anticancer drugs have steadily increased. The costs of novel therapeutics, such as targeted therapies and immunotherapy were accounted almost two-third of all antineoplastic agents in Taiwan. Moving forward, it will be necessary to discuss the economic impacts to clinical use of new therapeutics, while continuing to monitor and improve the quality of cancer therapy. In this review, we describe the epidemiology, disease screening policies and medication treatment policies for colorectal, lung, breast and liver cancer. We focus on the recent developments in cancer therapeutics, discuss the use of biomarkers, and finally consider the costs and the recent advances of anticancer medications in Taiwan.

A comparison of regorafenib and fruquintinib for metastatic colorectal cancer: a systematic review and network meta-analysis

BACKGROUND

The optimal treatment in the third-line and later-line setting for metastatic colorectal cancer (mCRC) has not been established. As reported, regorafenib and fruquintinib have shown to be superior to placebo in mCRC. However, no direct clinical comparison of regorafenib and fruquintinib has been conducted; we performed a systematic review and network meta-analysis to compare the efficacy and safety of regorafenib and fruquintinib.

METHODS

PubMed, Embase, and the Cochrane Library were systematically searched and randomized-controlled trials (RCTs) assessing the effect and safety of regorafenib or fruquintinib versus placebo for patients with mCRC were included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. After that, we performed pairwise direct meta-analyses (regorafenib vs. placebo and fruquintinib vs. placebo) and indirect comparison (regorafenib vs. fruquintinib) using network meta-analyses methods.

RESULTS

Three RCTs involving 1380 patients were included in the meta-analysis. In the direct meta-analysis, regorafenib and fruquintinib both showed survival benefits when compared with placebo. For the indirect comparison, fruquintinib shows no significant difference in OS compared to regorafenib (HR 0.97; 95% CI 0.64-1.46). Regarding PFS, there was a tendency that fruquintinib was superior to regorafenib (HR 0.65; 95% CI 0.39-1.08); however, there was no statistic difference. For the safety analysis, in indirect comparison, fruquintinib showed significant difference in all-grade toxicity compared to regorafenib (OR 0.73; 95% CI 0.65-0.82), especially in subgroup of proteinuria (OR 0.31; 95% CI 0.11-0.86). For the grade 3-5 toxicity, fruquintinib showed no significant difference when compared with regorafenib (OR 0.92; 95% CI 0.64-1.32).

CONCLUSION

Based on efficacy and safety, there was a tendency that fruquintinib was superior to regorafenib, as a whole, regorafenib and fruquintinib demonstrated similar clinical benefit for patients with refractory mCRC. It seems that fruquintinib has less toxic in all-grade toxicity when compared with regorafenib.

The Evolving Biomarker Landscape for Treatment Selection in Metastatic Colorectal Cancer

The approval of targeted therapies for metastatic colorectal cancer (mCRC) has led to important improvements in patient outcomes. However, it is still necessary to increase individualisation of treatments based on tumour genetic profiles to optimise efficacy, while minimising toxicity. As such, there is currently great focus on the discovery and validation of further biomarkers in mCRC, with many new potential prognostic and predictive markers being identified alongside developments in patient molecular profiling technologies. Here, we review data for validated and emerging biomarkers impacting treatment strategies in mCRC. We completed a structured literature search of the PubMed database to identify relevant publications, limiting for English-language publications published between 1 January 2014 and 11 July 2018. In addition, we performed a manual search of the key general oncology and CRC-focused congresses to identify abstracts reporting emerging mCRC biomarker data, and of ClinicalTrials.gov to identify ongoing clinical trials investigating emerging biomarkers in mCRC and/or molecular-guided clinical trials. There is solid evidence supporting the use of BRAF status as a prognostic biomarker and DYPD, UGT1A1, RAS, and microsatellite instability as predictive biomarkers in mCRC. There are a number of emerging biomarkers that may prove to be clinically relevant in the future to have prognostic (HPP1 methylation), predictive (HER3, microRNAs, anti-angiogenic markers, and CRC intrinsic subtypes), or both prognostic and predictive values (HER2, CpG island methylator phenotype, tumour mutational load, gene fusions, and consensus molecular subtypes). As such, new biomarker-led treatment strategies in addition to anti-epidermal growth factor receptor and anti-angiogenetic treatments are being explored. Biomarkers that are not recommended to be tested in clinical practice or are unlikely to be imminently clinically relevant for mCRC include thymidylate transferase, ERCC1, PIK3CA, and PTEN. We highlight the clinical utility of existing and emerging biomarkers in mCRC and provide recommended treatment strategies according to the biomarker status. An update on ongoing molecular-guided clinical trials is also provided.

SAPPHIRE: a randomised phase II study of planned discontinuation or continuous treatment of oxaliplatin after six cycles of modified FOLFOX6 plus panitumumab in patients with colorectal cancer

BACKGROUND

Fluorouracil (5-FU), leucovorin (LV) and oxaliplatin (FOLFOX) plus panitumumab therapy is a commonly used first-line chemotherapy for metastatic colorectal cancer (mCRC). However, the long-term administration of oxaliplatin is associated with peripheral neuropathy (PN). We investigated whether the planned discontinuation of oxaliplatin after FOLFOX plus panitumumab therapy can maintain efficacy and reduce PN incidence.

PATIENTS AND METHODS

Chemotherapy-naive patients with RAS wild-type mCRC, aged ≥20 years, were enrolled and received six cycles of modified FOLFOX6 (mFOLFOX6) plus panitumumab as induction therapy. Patients who completed induction therapy without progression were randomised to mFOLFOX6 plus panitumumab (group A) or to 5-FU/LV plus panitumumab (group B). The primary end-point was the progression-free survival (PFS) rate at 9 months after randomisation. The secondary end-points were PFS, overall survival (OS), time to treatment failure (TTF), response rate (RR) and safety.

RESULTS

In total, 164 patients were enrolled; of whom, 113 patients were then randomised (group A, n = 56; group B, n = 57). The median follow-up after randomisation was 19.6 months. The PFS rates at 9 months and median PFS were 46.4% (80% confidence interval [CI], 38.1-54.9) and 9.1 months (95% CI, 8.6-11.1) in group A, compared with 47.4% (80% CI, 39.1-55.8) and 9.3 months (95% CI, 6.0-13.0) in group B, respectively. RR, OS and TTF were also similar in both groups. Grade ≥2 PN incidence was lower in group B (9.3%) than in group A (35.7%).

CONCLUSION

Planned discontinuation of oxaliplatin after six cycles of mFOLFOX6 plus panitumumab is a potential treatment option in patients with mCRC, achieving similar efficacy while reducing oxaliplatin-associated PN compared with mFOLFOX6 plus panitumumab.

TRIAL REGISTRATION NUMBER

NCT02337946.

Fibrinogen-Albumin Ratio Index (FARI): A More Promising Inflammation-Based Prognostic Marker for Patients Undergoing Hepatectomy for Colorectal Liver Metastases

BACKGROUND

Systemic inflammation response is involved in the development and progression of cancers. This study aimed to evaluate the prognostic value of a preoperative Fibrinogen-Albumin Ratio Index (FARI) in patients undergoing hepatectomy for colorectal liver metastases (CRLM) and compare it with established systemic inflammation markers, including the neutrophil-lymphocyte ratio, lymphocyte-monocyte ratio, platelet-lymphocyte ratio, and systemic immune-inflammation index.

METHODS

Patients who underwent hepatectomy for CRLM between November 2002 and December 2016 were considered for inclusion. Time-dependent receiver operating characteristic (ROC) curve analysis was conducted to evaluate the ability of markers in predicting survival. Multivariable Cox regression analysis was used to identify independent predictors for overall survival (OS) or disease-free survival (DFS).

RESULTS

A total of 452 consecutive patients were enrolled. The areas under the ROC curve of the FARI in predicting OS and DFS were superior to other inflammatory markers and carcinoembryonic antigen (CEA). The optimal cut-off value of the FARI was 7.6%. Patients with a high FARI (> 7.6%) showed significantly decreased OS and DFS (all p < 0.001). In multivariable analysis, the FARI was the only inflammatory marker that independently predicted OS and DFS. Additionally, regardless of patients having a high or low CEA, the FARI further stratified these patients into subgroups with significantly distinct OS and DFS (all p < 0.05). The FARI also showed good clinical utility in patients with different clinical characteristics.

CONCLUSIONS

A preoperative FARI is an independent predictor of OS and DFS for patients undergoing hepatectomy for CRLM, superior to the established systemic inflammation markers and CEA.

Emergence of RAS mutations in patients with metastatic colorectal cancer receiving cetuximab-based treatment: a study protocol

BACKGROUND

In the management of patients with RAS wild-type metastatic colorectal cancer (mCRC), anti-epidermal growth factor receptor (EGFR) therapies have demonstrated a clinical benefit, with longer survival. However, the correlation between the emergence of circulating RAS mutations and secondary resistance to anti-EGFR therapies requires further elucidation. In this study, we aim to examine evolutionary changes in RAS mutations through liquid biopsy in patients with mCRC during and after anti-EGFR therapy.

METHODS

A total of 120 patients diagnosed with RAS wild-type mCRC will be enrolled in this study. Patients will receive a cetuximab-based infusional 5-fluorouracil regimen as first-line treatment. Cetuximab-based treatment is expected to continue until disease progression, intolerable toxic effects, or withdrawal of consent. Blood samples from enrolled patients will be collected before and then every 3 months during cetuximab-based treatment and also at disease progression. These blood samples will be evaluated for RAS resistance mutations by using the MassARRAY platform. The primary endpoint is the percentage of RAS mutations detected in circulating DNA from patients during cetuximab treatment. The correlation between the tumor response and survival outcomes of these patients and the emergence of circulating RAS mutations will be further analyzed.

DISCUSSION

Liquid biopsy is a powerful technology that can represent tumor heterogeneity in a relatively noninvasive manner. Because RAS mutations play a major role in resistance to anti-EGFR therapy for mCRC, examining evolutionary changes in these mutations during such treatment through liquid biopsy would be useful. After comprehensively analyzing the emergence of circulating RAS mutations and its clinical relevance in this study, our results should provide practical guidance on anti-EGFR therapy for mCRC.

TRIAL REGISTRATION

The date of trial registration ( NCT03401957 ) in this study was January 17, 2018.

Molecular targeted therapy of BRAF-mutant colorectal cancer

Over the past two decades, the molecular characterization of metastatic colorectal cancer (mCRC) has been revolutionized by the routine implementation of RAS and BRAF tests. As a result, it is now known that patients with mCRC harboring BRAF mutations experience a poor prognosis. Although it accounts for only 10% of mCRC, this group is heterogeneous; only the BRAF-V600E mutation, also observed in melanoma, is associated with a very poor prognosis. In terms of treatment, these patients do not benefit from therapeutics targeting the epidermal growth factor receptor (EGFR). In first-line chemotherapy, there are two main options; the first one is to use a triple chemotherapy combination of 5-fluorouracil, irinotecan, and oxaliplatin, with the addition of bevacizumab, because post hoc analysis of randomized trials have reported interesting results. The other option is to use double chemotherapy plus bevacizumab, since anti-EGFR seems to have modest activity in these patients. Only a small percentage of patients who experience failure of this first-line treatment receive second-line treatment. Monotherapy with BRAF inhibitors has failed in this setting, and different combinations have also been tested. Using the rationale that BRAF inhibitor monotherapy fails due to feedback activation of the EGFR pathway, BRAF inhibitors have been combined with anti-EGFR agents plus or minus MEK inhibitors; however, the results did not live up to the hopes raised by the concept. To date, the best results in second-line treatment have been obtained with a combination of vemurafenib, cetuximab, and irinotecan. Despite these advances, further improvements are needed.

A Systematic Review and Network Meta-Analysis of Regorafenib and TAS-102 in Refractory Metastatic Colorectal Cancer

BACKGROUND

Regorafenib at different dosing strategies and TAS-102 are treatment options for refractory metastatic colorectal cancer (mCRC). We aimed to evaluate the comparative effectiveness evidence supporting these different strategies.

MATERIALS AND METHODS

We searched different databases for randomized controlled trials evaluating TAS-102 or regorafenib in patients with refractory mCRC who failed prior oxaliplatin, irinotecan, and fluoropyrimidine. Outcomes of interest included overall survival (OS) and progression-free survival (PFS). The overall effect was pooled using the DerSimonian random effects model. We conducted network meta-analysis based on White's multivariate meta-regression to pool evidence from direct and indirect comparisons.

RESULTS

Six trials at low risk of bias (2,445 patients) were included. Direct comparisons showed that Rego 160 and TAS-102 as monotherapy were superior to best-supportive care (BSC) in terms of PFS (Rego 160: hazard ratio [HR], 0.4; 95% confidence ratio [CI], 0.26-0.63; TAS-102: HR, 0.46 CI, 0.40-0.52) and OS (Rego 160: HR, 0.67; CI, 0.48-0.93; TAS-102: HR, 0.67; CI, 0.57-0.80). Network analysis showed no statistically difference in PFS or OS between Rego 160 and TAS-102. Rego 80+ was superior to BSC in terms of OS (HR, 0.44; CI, 0.23-0.84) and PFS (HR, 0.37; CI, 0.21-0.66). Rego 80+ was associated with statistically nonsignificant improvement in OS and PFS compared with TAS-102 and Rego 160.

CONCLUSION

Regorafenib 160 and TAS-102 appear to have similar efficacy. Rego 80+ is shown to be superior to BSC. A trend for improved OS was observed with Rego 80+ versus Rego 160 or TAS 102.

IMPLICATIONS FOR PRACTICE

Regorafenib at a dose of 160 mg and TAS-102 appear to have similar efficacy in patients with refractory metastatic colorectal cancer. Regorafenib with a dose escalation strategy is superior to best-supportive care. Given its tolerability and the observed trend in survival benefit compared with regorafenib 160, dose escalation strategy of regorafenib (80+) may be the preferred option in this setting.

Efficacy and safety assessment of S-1-based regimens comparing to intravenous fluorouracil-based ones in Asian patients with metastatic colorectal carcinoma: A system review and meta-analysis

BACKGROUND

We performed the present systematic review and meta-analysis to evaluate the efficacy and safety for S-1-based regimens comparing to intravenous fluorouracil-based ones in Asian patients with metastatic colorectal carcinoma (mCRC).

METHODS

Eligible prospective and controlled randomized clinical trials (RCT) were included, of which data were extracted by inclusion criteria and exclusion ones. Odds ratio (OR) and Hazard ratio (HR) of outcomes including objective response rate (ORR), disease control rate (DCR), progressive-free survival (PFS), overall survival (OS), and adverse events (AEs) were explored for the final analysis between the 2 groups.

RESULTS

A total of 23 eligible prospective, controlled RCTs including 2269 patients were enrolled for the pooled analysis. With the meta-analysis of available data, the results of the present research showed that there was no statistical difference on short-term efficacy including ORR (HR = 0.85, 95% CI: 0.71-1.01; P = .07) or DCR (HR = 0.88, 95% CI: 0.69-1.11; P = .27), as well as long-term efficacy including PFS (HR = 1.00, 95% CI: 0.90-1.11; P = .98) or OS (HR = 0.95, 95% CI: 0.82-1.10; P = .50). In addition, the incidences of AEs including leucopenia, neutropenia, and vomiting were statistically lower in S-1-based regimens comparing to intravenous fluorouracil-based ones, regardless of all grade or high grade (all P <.05). However, there were no significant differences detected among other AEs including anemia, thrombocytopenia, increased alanine aminotransferase concentration, stomatitis, anorexia, diarrhea, hand-foot syndrome (HFS), or sensory neuropathy among the 2 groups (all P >.05).

CONCLUSIONS

The present meta-analysis revealed that S-1-based regimens might be associated with comparable efficacy, as well as lower risk of leucopenia, neutropenia, and vomiting at all/high grade comparing to intravenous fluorouracil-based ones in Asian patients with mCRC.

Regorafenib: A Review in Metastatic Colorectal Cancer

Regorafenib (Stivarga^®) is an oral small-molecule multiple kinase inhibitor. It is indicated worldwide for patients with metastatic colorectal cancer (mCRC). In the EU and USA it is indicated for patients with mCRC who have been previously treated with, or are not considered candidates for available therapies, including fluoropyrimidine-based chemotherapy, an anti-VEGF therapy and, if RAS wild-type, an anti-EGFR therapy. In Japan, it is indicated for the treatment of unresectable, advanced/recurrent CRC. The addition of regorafenib to best supportive care prolonged median overall survival (OS; by up to 2.5 months) and progression-free survival (PFS; by up to 1.5 months) relative to the addition of placebo in double-blind phase 3 studies (CORRECT and CONCUR) in patients with mCRC who had progressed after failure of standard therapy. Health-related quality of life was not adversely affected with regorafenib relative to placebo. A large open-label phase 3 study (CONSIGN) and several large real-world studies supported the efficacy of regorafenib in this setting. Regorafenib had a generally manageable tolerability profile, which was consistent with the profile of a typical small-molecule multiple kinase inhibitor. Treatment-related adverse events (AEs), mostly of mild or moderate severity, were reported in the majority of patients receiving regorafenib, with dermatological toxicities and liver enzyme elevations among the most common AEs. Although identification of biomarkers/parameters predicting efficacy outcomes with regorafenib will help to individualize therapy, current evidence indicates that regorafenib is a valuable treatment option for patients with refractory mCRC who have a very poor prognosis.

Peritoneal dissemination of ascending colon cancer demonstrating relapse-free survival for 40 months with panitumumab monotherapy: A case report

INTRODUCTION

The prognosis of metastatic colorectal cancer (mCRC) patients receiving multiple cytotoxic agents and targeted therapies (CATT) has improved, but a complete cure by CATT is still very rare.

PRESENTATION OF CASE

We report the successful treatment of ascending colon cancer complicated by peritoneal disseminations (PDs) with panitumumab (Pmab) plus mFOLFOX6 therapy. A 67-year-old male patient was diagnosed with clinical stage IV cancer of the ascending colon with PDs, and underwent ileostomy. Eighteen courses of Pmab plus mFOLFOX6 caused remarkable tumor shrinkage and the disappearance of PDs on ECT. Laparotomy revealed tumor shrinkage and scarring at the PD sites. We performed right hemicolectomy, subtotal omentectomy, and ileostomy closure as curability B surgery. Seven months later, new PDs were detected by ECT so we resumed Pmab plus mFOLFOX6 therapy. After nine courses of treatment, the target lesion had completely disappeared. After a total of 20 courses, we changed to Pmab monotherapy as maintenance therapy because there was no recurrence. Forty months after the initiation of Pmab monotherapy, there has been no oncologic progression.

DISCUSSION

Pmab plus mFOLFOX6 treatment resulted in a complete response for PDs, which is extremely rare for CATT.

CONCLUSION

We consider that Pmab therapy should be introduced for the treatment of mCRC complicated by PDs.

Non-V600E BRAF mutations and EGFR signaling pathway in colorectal cancer

The Raf murine sarcoma viral oncogene homolog B (BRAF^V600E ) mutation (MT) in metastatic colorectal cancer (CRC) is a well-known prognostic indicator and a negative predictive biomarker for antiepidermal growth factor receptor (EGFR) treatment. However, the clinical characteristics and significance of BRAF^non-V600E MTs remain unclear. Here, we evaluated the clinical characteristics of BRAF^non-V600E MTs vs. those of other MTs in the EGFR signaling pathway, including BRAF^V600E . Consecutive CRC patients in our institute from June 2012 to November 2013 were enrolled in our study. Multiplex genotyping of the EGFR pathway was performed with archival samples using a Luminex Assay for BRAF^V600E /BRAF^non-V600E , KRAS/NRAS exons 2-4, and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA). We analyzed correlations among the MT profiles, clinical data and primary tumor locations in CRC. All statistical analyses were performed using R software. CRC samples (824) from 374 (45.4%) male and 450 (54.6%) female patients were analyzed, of which 154 (18.7%), 202 (24.5%), 270 (32.8%) or 198 (24.0%) had Stages I, II, III or IV or recurrent CRC, respectively. The frequencies of BRAF^V600E /BRAF^non-V600E , KRAS (including exons 2-4), NRAS and PIK3CA MTs were 5.3/1.7, 41.4, 3.3 and 9.6%, respectively. The characteristics of patients with the BRAF^V600E MT were an age of ≥65 years old, a right-sided primary tumor location, poorly differentiated histology and an advanced disease stage. In contrast, the characteristics of patients with BRAF^non-V600E MTs were a left-sided primary tumor location and well-differentiated histology. BRAF^non-V600E MTs were relatively rare and showed different characteristics compared to the BRAF^V600E MT. These results may contribute to future precision medicine.

A multicentre, prospective study of plasma circulating tumour DNA test for detecting RAS mutation in patients with metastatic colorectal cancer

BACKGROUND

OncoBEAMTM RAS CRC kit using BEAMing technology is a circulating tumour DNA (ctDNA) test for detecting plasma RAS mutational status in metastatic colorectal cancer (mCRC). We conducted a multicentre, prospective study to investigate the concordance of the RAS mutational status between plasma ctDNA and tumour tissue DNA.

METHODS

mCRC patients without prior anti-EGFR antibodies or regorafenib treatment were enroled. Plasma- and tissue-based RAS mutational status were determined by BEAMing, respectively.

RESULTS

A total of 280 patients from eight institutions were eligible. The overall agreement between plasma- and tissue-based analyses was 86.4%, with a positive percent agreement of 82.1% and negative percent agreement of 90.4%. From logistic regression analysis, lung metastasis alone indicated the most significant factor associated with discordance. The agreement between plasma- and tissue-based analyses was 64.5% in patients with lung metastasis alone (n = 31) indicating lower amount of ctDNA. Among the cases with lung metastasis alone, all plasma- and tissue-based analyses were perfectly concordant in cases with ≥20 mm of maximum lesion diameter or ≥10 lesions.

CONCLUSION

The clinical validity of OncoBEAMTM RAS CRC kit was confirmed. Careful attention should be paid for mCRC patients with lung metastases alone having fewer metastases or smaller diameter lesions.

Two cases of lymphangitic carcinomatosis as the primary symptom of colorectal carcinoma that achieved complete remission using combination anti-EGFR antibody therapy

Clinicians often encounter cases of pulmonary lymphangitic carcinomatosis when treating patients with cancer. When such a condition develops before the diagnosis of cancer, its diagnosis is often challenging. Herein, we report about two patients with colorectal carcinoma diagnosed after the identification of lymphangitic carcinomatosis, which achieved complete remission with combination anti-epidermal growth factor receptor (anti-EGFR) antibody therapy. In case 1, a 74-year-old woman presented with cough and dyspnea that had persisted for 1 month. She had unresectable advanced carcinoma of the sigmoid colon with lymphangitic carcinomatosis. Her respiratory status gradually deteriorated due to the disease. Thus, FOLFIRI plus cetuximab therapy was initiated. Her dyspnea rapidly resolved with the treatment, and complete remission of lymphangitic carcinomatosis was achieved. In case 2, a 46-year-old man presented with fever and dyspnea that had persisted for 1 month. He had unresectable advanced carcinoma of the transverse colon with lymphangitic carcinomatosis. FOLFOXIRI therapy was then initiated. However, his respiratory status did not improve. Therefore, his treatment was immediately switched to FOLFIRI plus panitumumab. His dyspnea rapidly resolved with the treatment, and complete remission of lymphangitic carcinomatosis was achieved. In oncologic emergencies, such as lymphangitic carcinomatosis, requiring an early response to treatment, the administration of anti-EGFR antibodies may be a highly effective treatment option.

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

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

First-line therapy for metastatic colorectal cancer: Current perspectives and future directions

The prognosis for patients with newly diagnosed inoperable metastatic colorectal cancer has steadily improved over the past two decades as new agents have been introduced into clinical practice and many new biomarkers have been discovered. In parallel with this progress, clinicians face increasingly complex treatment decisions. This review summarizes recent progress, with a historical perspective, which should help guide the clinician in decision making and optimal therapy selection. This review not only focuses on important and readily identifiable subsets, including primary tumor side and v-RAF murine sarcoma viral oncogene homologue B (BRAF) mutations, but also discusses rarer molecular subgroups that may be important for determining treatment in the future.

A phase I study to determine the maximum tolerated dose of trifluridine/tipiracil and oxaliplatin in patients with refractory metastatic colorectal cancer: LUPIN study

Background The effectiveness of reintroducing oxaliplatin for metastatic colorectal cancer (mCRC) refractory to both oxaliplatin and irinotecan was previously reported in a phase II study (RE-OPEN). We conducted a phase I study to determine the maximum tolerated dose of oxaliplatin plus trifluridine/tipiracil (FTD/TPI) in patients with refractory mCRC. Patients and Methods Three dosages of intravenous oxaliplatin (50, 65 and 85 mg/m²) on days 1 and 15 and a fixed dose of FTD/TPI 35 mg/m² twice daily (bid) on days 1-5 and 15-19 every 4 weeks were investigated in patients with refractory mCRC using a 3 + 3 design. Eligible patients had received prior oxaliplatin-based treatment that achieved a response or stable disease followed by confirmed disease progression at least 6 months before entering the study. Results Twelve patients were enrolled in the study. Three of six patients in the oxaliplatin 85 mg/m² cohort had dose-limiting toxicities (DLTs) with treatment delays during the second cycle at ≥8 days due to grade ≥ 2 neutropenia or grade 2 AST/ALT increased. No DLTs were observed in the other cohorts. Grade ≥ 3 AEs were neutropenia (n = 3), thrombocytopenia (n = 1), anorexia (n = 1), and nausea (n = 1). There was no evidence of allergic reaction to oxaliplatin or severe peripheral sensory neuropathy. Conclusions A combination of FTD/TPI 35 mg/m² bid on days 1-5 and 15-19 and oxaliplatin 85 mg/m² on days 1 and 15 every 4 weeks could be a suitable regimen for the recommended dose of FTD/TPI plus oxaliplatin in patients with refractory mCRC.

Clinical utility of circulating tumor DNA for colorectal cancer

Colorectal cancer (CRC) is currently the most common type of cancer in Japan, and its prognosis has improved because of development of diagnosis and advancement in treatments including surgery and chemotherapy. However, because of intratumor heterogeneity and clonal evolution, tumors often develop resistance to treatment. Genotyping tumor tissue in search of somatic genetic alterations for actionable information has become routine examination in clinical practice. However, the inherent molecular heterogeneity of metastatic tumors and the ability of cancer genomes to dynamically evolve are not properly captured by tissue specimens only. Circulating tumor DNA (ctDNA) carrying tumor‐specific genetic or epigenetic alterations is released into the circulation from tumor cells undergoing apoptosis or necrosis. Analysis of ctDNA has the potential to change clinical practice by exploiting blood rather than tissue, as a source of information. Here, we provide an overview of the characteristics of ctDNA and focus on detection methods for ctDNA, and the feasibility of use of ctDNA to monitor tumor dynamics for patients with colorectal cancer.

Pan-Asian adapted Clinical Practice Guidelines for the management of patients with metastatic non-small-cell lung cancer: a CSCO-ESMO initiative endorsed by JSMO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of metastatic non-small-cell lung cancer (NSCLC) was published in 2016. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and the Chinese Society of Clinical Oncology (CSCO) to convene a special guidelines meeting immediately after the Chinese Thoracic Oncology Group Annual Meeting 2018, in Guangzhou, China. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic NSCLC cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic NSCLC representing the oncological societies of China (CSCO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and was independent of both the current treatment practices and the drug availability and reimbursement situations in the six participating Asian countries. During the review process, the updated ESMO 2018 Clinical Practice Guidelines for metastatic NSCLC were released and were also considered, during the final stages of the development of the Pan-Asian adapted Clinical Practice Guidelines.

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

BACKGROUND

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Impact of primary tumor location as a predictive factor in patients suffering from colorectal cancer treated with cytotoxic anticancer agents based on the collagen gel droplet-embedded drug sensitivity test

In recent studies, better clinical outcomes for patients with left-sided colon cancer (CC) compared with right-sided CC have been reported; however, in such investigations, the chemotherapy regimens included molecular-targeting agents. To the best of our knowledge, the impact of primary tumor location as a predictive factor in patients suffering from CC treated with cytotoxic anticancer agents alone has not been investigated. The aim of the present study was to determine the impact of the primary tumor location as a predictive factor of patients undergoing the following cytotoxic anticancer agent regimens: Leucovorin and fluorouracil + oxaliplatin (FOLFOX) or Leucovorin and fluorouracil + irinotecan (FOLFIRI), using the collagen gel droplet-embedded drug sensitivity test (CD-DST). Between March 2008 and April 2017, tumor specimens were obtained from 133 patients suffering from colorectal cancer (CRC) who had not received preoperative chemotherapy. CD-DST was performed and the growth inhibition rate (IR) was determined in FOLFOX and FOLFIRI regimens. The associations between tumor location and IR values for each condition were evaluated. In the present study, the prognosis of patients receiving palliative chemotherapy as well as treatment with molecularly-targeted agents was also investigated. There were no significant differences in the IRs (%) of the two regimens using CD-DST for right-sided tumors compared with left-sided tumors, including or excluding the rectum. The median survival times of patients with right CC and left CC who had received palliative chemotherapy and treatment with molecularly-targeted agents were 960 and 1,348 days, respectively. Primary tumor location did not represent a predictive factor for the efficacy of treatment with cytotoxic anticancer agent regimens using CD-DST. However, patients suffering from left-sided CC were revealed to exhibit better clinical outcomes compared with patients suffering from right-sided CC when molecularly-targeted agent regimens were administered. Therefore, the results of the present study suggested that molecularly-targeted agents rather than cytotoxic anticancer agents may result in improved clinical outcomes for patients with CRC suffering from left-sided tumors.

Emerging microRNA biomarkers for colorectal cancer diagnosis and prognosis

MicroRNAs (miRNAs) are one abundant class of small, endogenous non-coding RNAs, which regulate various biological processes by inhibiting expression of target genes. miRNAs have important functional roles in carcinogenesis and development of colorectal cancer (CRC), and emerging evidence has indicated the feasibility of miRNAs as robust cancer biomarkers. This review summarizes the progress in miRNA-related research, including study of its oncogene or tumour-suppressor roles and the advantages of miRNA biomarkers for CRC diagnosis, treatment and recurrence prediction. Along with analytical technique improvements in miRNA research, use of the emerging extracellular miRNAs is feasible for CRC diagnosis and prognosis.

Colorectal Cancer Biomarkers in the Era of Personalized Medicine

The 5-year survival probability for patients with metastatic colorectal cancer has not drastically changed over the last several years, nor has the backbone chemotherapy in first-line disease. Nevertheless, newer targeted therapies and immunotherapies have been approved primarily in the refractory setting, which appears to benefit a small proportion of patients. Until recently, rat sarcoma (RAS) mutations remained the only genomic biomarker to assist with therapy selection in metastatic colorectal cancer. Next generation sequencing has unveiled many more potentially powerful predictive genomic markers of therapy response. Importantly, there are also clinical and physiologic predictive or prognostic biomarkers, such as tumor sidedness. Variations in germline pharmacogenomic biomarkers have demonstrated usefulness in determining response or risk of toxicity, which can be critical in defining dose intensity. This review outlines such biomarkers and summarizes their clinical implications on the treatment of colorectal cancer. It is critical that clinicians understand which biomarkers are clinically validated for use in practice and how to act on such test results.

Biomarker analysis beyond angiogenesis: RAS/RAF mutation status, tumour sidedness, and second-line ramucirumab efficacy in patients with metastatic colorectal carcinoma from RAISE-a global phase III study

Background

: Second-line treatment with ramucirumab+FOLFIRI improved overall survival (OS) versus placebo+FOLFIRI for patients with metastatic colorectal carcinoma (CRC) [hazard ratio (HR)=0.84, 95% CI 0.73-0.98, P = 0.022]. Post hoc analyses of RAISE patient data examined the association of RAS/RAF mutation status and the anatomical location of the primary CRC tumour (left versus right) with efficacy parameters.

Patients and methods

Patient tumour tissue was classified as BRAF mutant, KRAS/NRAS (RAS) mutant, or RAS/BRAF wild-type. Left-CRC was defined as the splenic flexure, descending and sigmoid colon, and rectum; right-CRC included transverse, ascending colon, and cecum.

Results

RAS/RAF mutation status was available for 85% of patients (912/1072) and primary tumour location was known for 94.4% of patients (1012/1072). A favourable and comparable ramucirumab treatment effect was observed for patients with RAS mutations (OS HR = 0.86, 95% CI 0.71-1.04) and patients with RAS/BRAF wild-type tumours (OS HR = 0.86, 95% CI 0.64-1.14). Among the 41 patients with BRAF-mutated tumours, the ramucirumab benefit was more notable (OS HR = 0.54, 95% CI 0.25-1.13), although, as with the other genetic sub-group analyses, differences were not statistically significant. Progression-free survival (PFS) data followed the same trend. Treatment-by-mutation status interaction tests (OS P = 0.523, PFS P = 0.655) indicated that the ramucirumab benefit was not statistically different among the mutation sub-groups, although the small sample size of the BRAF group limited the analysis. Addition of ramucirumab to FOLFIRI improved left-CRC median OS by 2.5 month over placebo (HR = 0.81, 95% CI 0.68-0.97); median OS for ramucirumab-treated patients with right-CRC was 1.1 month over placebo (HR = 0.97, 95% CI 0.75-1.26). The treatment-by-sub-group interaction was not statistically significant for tumour sidedness (P = 0.276).

Conclusions

In the RAISE study, the addition of ramucirumab to FOLFIRI improved patient outcomes, regardless of RAS/RAF mutation status, and tumour sidedness. Ramucirumab treatment provided a numerically substantial benefit in BRAF-mutated tumours, although the P-values were not statistically significant.

ClinicalTrials.gov number

NCT01183780.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the management of patients with metastatic oesophageal cancer: a JSMO-ESMO initiative endorsed by CSCO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of oesophageal cancer was published in 2016, and covered the management and treatment of local/locoregional disease, limited disease, locally advanced disease and the management of advanced/metastatic disease. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting immediately after the JSMO Annual Meeting in 2018. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic oesophageal cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic oesophageal cancer representing the oncological societies of Japan (JSMO), China (CSCO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the management of patients with metastatic gastric cancer: a JSMO-ESMO initiative endorsed by CSCO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of gastric cancer (GC) was published in 2016, and covered the management and treatment of local, locoregional, locally advanced and metastatic disease. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and The Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting immediately after the JSMO Annual Meeting in 2018. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic GC in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic GC representing the oncological societies of Japan (JSMO), China (CSCO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

Early-onset colorectal cancer in young individuals

Treatment of young adults with colorectal cancer (CRC) represents an unmet clinical need, especially as diagnosis in this population might lead to the greatest loss of years of life. Since 1994, CRC incidence in individuals younger than 50 years has been increasing by 2% per year. The surge in CRC incidence in young adults is particularly alarming as the overall CRC frequency has been decreasing. Early-onset CRC are characterized by a more advanced stage at diagnosis, poorer cell differentiation, higher prevalence of signet ring cell histology, and left colon-sided location of the primary tumor. Among EO-CRC, approximately 30% of patients are affected by tumors harboring mutations causing hereditary cancer predisposing syndromes, and 20% have familial CRC. Most notably, the remaining 50% of EO-CRC patients have neither hereditary syndromes nor familial CRC, thus representing a formidable challenge for research. In this review article we summarize epidemiology, clinical and molecular features, heredity and outcome of treatments of EO-CRC, and provide considerations for future perspectives.

SEOM clinical guidelines for diagnosis and treatment of metastatic colorectal cancer (2018)

Colorectal cancer (CRC) is the second cause of cancer death in Spain, the objective of this guide published by the Spanish Society of Medical Oncology is to develop a consensus for the diagnosis and management of metastatic disease. The optimal treatment strategy for patients with metastatic CRC should be discussed in a multidisciplinary expert team to select the most appropriate treatment, and integrate systemic treatment and other options such as surgery and ablative techniques depending on the characteristics of the tumour, the patient and the location of the disease and metastases.

Considering FOLFOXIRI plus bevacizumab for metastatic colorectal cancer with left-sided tumors

A recent subgroup analysis of the TRIBE trial suggested that FOLFOXIRI plus bevacizumab may be a preferred option for the first-line treatment of only right-sided metastatic colorectal cancer (mCRC), regardless of RAS or BRAF status. Our subanalysis of a phase II trial of the FOLFOXIRI triplet regimen plus bevacizumab in patients with mCRC who had RAS mutant tumors showed that tumor shrinkage was better and the duration of treatment was longer in patients with left-sided tumors than in those with right-sided tumors, leading to a higher rate of conversion to surgery in mCRC patients with left-sided tumors. The early and deep responses to the triplet-regimen in patients with left-sided tumors might facilitate conversion treatment resulting in favorable survival. Our data suggest that the FOLFOXIRI plus bevacizumab might be a promising treatment for left-sided mCRC involving RAS mutant tumors.

Impact of primary tumor location as a predictive factor in patients suffering from colorectal cancer treated with cytotoxic anticancer agents based on the collagen gel droplet-embedded drug sensitivity test

In recent studies, better clinical outcomes for patients with left-sided colon cancer (CC) compared with right-sided CC have been reported; however, in such investigations, the chemotherapy regimens included molecular-targeting agents. To the best of our knowledge, the impact of primary tumor location as a predictive factor in patients suffering from CC treated with cytotoxic anticancer agents alone has not been investigated. The aim of the present study was to determine the impact of the primary tumor location as a predictive factor of patients undergoing the following cytotoxic anticancer agent regimens: Leucovorin and fluorouracil + oxaliplatin (FOLFOX) or Leucovorin and fluorouracil + irinotecan (FOLFIRI), using the collagen gel droplet-embedded drug sensitivity test (CD-DST). Between March 2008 and April 2017, tumor specimens were obtained from 133 patients suffering from colorectal cancer (CRC) who had not received preoperative chemotherapy. CD-DST was performed and the growth inhibition rate (IR) was determined in FOLFOX and FOLFIRI regimens. The associations between tumor location and IR values for each condition were evaluated. In the present study, the prognosis of patients receiving palliative chemotherapy as well as treatment with molecularly-targeted agents was also investigated. There were no significant differences in the IRs (%) of the two regimens using CD-DST for right-sided tumors compared with left-sided tumors, including or excluding the rectum. The median survival times of patients with right CC and left CC who had received palliative chemotherapy and treatment with molecularly-targeted agents were 960 and 1,348 days, respectively. Primary tumor location did not represent a predictive factor for the efficacy of treatment with cytotoxic anticancer agent regimens using CD-DST. However, patients suffering from left-sided CC were revealed to exhibit better clinical outcomes compared with patients suffering from right-sided CC when molecularly-targeted agent regimens were administered. Therefore, the results of the present study suggested that molecularly-targeted agents rather than cytotoxic anticancer agents may result in improved clinical outcomes for patients with CRC suffering from left-sided tumors.

Irinotecan toxicity during treatment of metastatic colorectal cancer: focus on pharmacogenomics and personalized medicine

Colorectal cancer, one of the most frequent types of cancer worldwide, has a high mortality rate. Irinotecan (CPT-11) has been approved for the treatment of advanced or metastatic disease either as a single agent or, more commonly, as part of combined chemotherapeutic regimens. Treatment with irinotecan is often accompanied by severe toxicity (e.g. neutropenia and diarrhea) that can result in treatment interruption or cessation, thus jeopardizing the patient's prognosis and quality of life. Irinotecan is bioactivated into its metabolite SN-38, which is subsequently detoxified by uridine diphosphate-glucuronosyl transferases (mainly UGT1A1). Further, ABC transporters (i.e. ABCB1, ABCC1-ABCC6, and ABCG2) are responsible for drug efflux into bile and urine whereas OATP transporters (SLCO1B1) enable its influx from blood into hepatocytes. Genetic polymorphisms in these enzymes/pumps may result in increased systemic SN-38 level, directly correlating with toxicity. Contemporary research is focused on the clinical implementation of genetic screenings for validated gene variations prior to treatment onset, allowing tailored individual doses or treatment regimens.