Elisa Fontana

Novel targets in the treatment of advanced gastric cancer: a perspective review

Gastric cancer is responsible for a high burden of disease globally. Although more extensive use of chemotherapy together with the recent introduction of the two targeted agents trastuzumab and ramucirumab have contributed to marginal outcome prolongation, overall survival for patients with advanced stage disease remains poor. Over the last decade, a number of novel agents have been examined in clinical trials with largely disappointing results. Potential explanations for this are the absence of molecularly selected trial populations or weak predictive biomarkers within the context of a highly heterogeneous disease. In the recently published gastric cancer The Cancer Genome Atlas (TCGA) project a new classification of four different tumour subtypes according to different molecular characteristics has been proposed. With some overlap, several relatively distinct and potentially targetable pathways have been identified for each subtype. In this perspective review we match recent trial results with the subtypes described in the gastric cancer TCGA aiming to highlight data regarding novel agents under evaluation and to discuss whether this publication might provide a framework for future drug development.

Functional imaging and circulating biomarkers of response to regorafenib in treatment-refractory metastatic colorectal cancer patients in a prospective phase II study

Objective Regorafenib demonstrated efficacy in patients with metastatic colorectal cancer (mCRC). Lack of predictive biomarkers, potential toxicities and cost-effectiveness concerns highlight the unmet need for better patient selection. Design Patients with RAS mutant mCRC with biopsiable metastases were enrolled in this phase II trial. Dynamic contrast-enhanced (DCE) MRI was acquired pretreatment and at day 15 post-treatment. Median values of volume transfer constant (Ktrans), enhancing fraction (EF) and their product KEF (summarised median values of Ktrans× EF) were generated. Circulating tumour (ct) DNA was collected monthly until progressive disease and tested for clonal RAS mutations by digital-droplet PCR. Tumour vasculature (CD-31) was scored by immunohistochemistry on 70 sequential tissue biopsies. Results Twenty-seven patients with paired DCE-MRI scans were analysed. Median KEF decrease was 58.2%. Of the 23 patients with outcome data, >70% drop in KEF (6/23) was associated with higher disease control rate (p=0.048) measured by RECIST V. 1.1 at 2 months, improved progression-free survival (PFS) (HR 0.16 (95% CI 0.04 to 0.72), p=0.02), 4-month PFS (66.7% vs 23.5%) and overall survival (OS) (HR 0.08 (95% CI 0.01 to 0.63), p=0.02). KEF drop correlated with CD-31 reduction in sequential tissue biopsies (p=0.04). RAS mutant clones decay in ctDNA after 8 weeks of treatment was associated with better PFS (HR 0.21 (95% CI 0.06 to 0.71), p=0.01) and OS (HR 0.28 (95% CI 0.07–1.04), p=0.06). Conclusions Combining DCE-MRI and ctDNA predicts duration of anti-angiogenic response to regorafenib and may improve patient management with potential health/economic implications.

Anti-angiogenic therapies for advanced esophago-gastric cancer.

Neo-vascularization is a vital process for tumor growth and development which involves the interaction between tumor cells and stromal endothelial cells through several growth factors and membranous receptors which ultimately activate pro-angiogenic intracellular signaling pathways. Inhibition of angiogenesis has become a standard treatment option for several tumor types including colorectal cancer, glioblastoma and ovarian cancer. In gastric cancer, the therapeutic role of anti-angiogenic agents is more controversial. Bevacizumab and ramucirumab, two monoclonal antibodies, which target vascular endothelial growth factor-A and vascular endothelial growth factor receptor-2, respectively, have been demonstrated antitumor activity in patients with tumors of the stomach or esophagogastric junction. However, especially for bevacizumab, this antitumor activity has not consistently translated into a survival advantage over standard treatment in randomized trials. In this article, we provide an overview of the role of angiogenesis in gastric cancer and discuss the results of clinical trials that investigated safety and effectiveness of antiangiogenic therapies in this disease. A review of the literature has been done using PubMed, ClinicalTrials.gov website and the ASCO Annual Meeting Library.

A Low-Cost Multiplex Biomarker Assay Stratifies Colorectal Cancer Patient Samples into Clinically-Relevant Subtypes

Previously, we classified colorectal cancers (CRCs) into five CRCA subtypes with different prognoses and potential treatment responses, using a 786-gene signature. We merged our subtypes and those described by five other groups into four consensus molecular subtypes (CMS) that are similar to CRCA subtypes. Here we demonstrate the analytical development and application of a custom NanoString platform-based biomarker assay to stratify CRC into subtypes. To reduce costs, we switched from the standard protocol to a custom modified protocol (NanoCRCA) with a high Pearson correlation coefficient (>0.88) between protocols. Technical replicates were highly correlated (>0.96). The assay included a reduced robust 38-gene panel from the 786-gene signature that was selected using an in-laboratory developed computational pipeline of class prediction methods. We applied our NanoCRCA assay to untreated CRCs including fresh-frozen and formalin-fixed paraffin-embedded (FFPE) samples (n=81) with matched microarray or RNA-Seq profiles. We further compared the assay results with CMS classification, different platforms (microarrays/RNA-Seq) and gene-set classifiers (38 and 786 genes). NanoCRCA classified fresh-frozen samples (n=39; not including those showing a mixture of subtypes) into all five CRCA subtypes with overall high concordance across platforms (89.7%) and with CMS subtypes (84.6%), independent of tumour cellularity. This analytical validation of the assay shows the association of subtypes with their known molecular, mutational and clinical characteristics. Overall, our modified NanoCRCA assay with further clinical assessment may facilitate prospective validation of CRC subtypes in clinical trials and beyond. Novelty and Impact We previously identified five gene expression-based CRC subtypes with prognostic and potential predictive differences using a 786-gene signature and microarray platform. Subtype-driven clinical trials require a validated assay suitable for routine clinical use. This study demonstrates, for the first time, how molecular CRCA subtype can be detected using NanoString Technology-based biomarker assay (NanoCRCA) suitable for clinical validation. NanoCRCA is suitable for analysing FFPE samples, and this assay may facilitate patient stratification within clinical trials.Objective: In order to personalise standard therapies based on molecular profiles, we previously classified colorectal cancers (CRCs) into five distinct subtypes (CRCAssigner) and later into four consensus molecular subtypes (CMS) with different prognoses and treatment responses. For clinical application, here we developed a low-cost multiplex biomarker assay. Design: Three cohorts of untreated fresh frozen CRC samples (n=57) predominantly from primary tumours and profiled by microarray/RNA-Seq were analysed. A reduced 38-gene panel (CRCAssigner-38) was selected from the published 786-gene CRCAssigner signature (CRCAssigner-786) using an in-house gene selection approach. A customised NanoString Technologies nCounter platform-based assay (NanoCRCAssigner) was developed for comparison with different classifiers (CMS subtypes), platforms (microarrays and RNA-Seq), and gene sets (CRCAssigner-38 and CRCAssigner-786). Results: NanoCRCAssigner classified samples (n=48; except those showing a mixture of subtypes) into all five CRCAssigner subtypes with overall high concordance across platforms (> 87%) and with CMS subtypes (81%) irrespective of variable tumour cellularity. The association of subtypes with their known molecular (microsatellite-instable and stemness), mutational (KRAS/BRAF), and clinical characteristics (including overall survival) further demonstrated assay validity. To reduce costs, we switched from the standard protocol to a low-cost protocol with a high Pearson correlation co-efficient (0.9) between protocols. Technical replicates were highly correlated (0.98). Conclusion: Here we developed a low-cost and potentially clinically deployable NanoCRCAssigner assay to facilitate prospective validation of (CRCAssigner and potentially CMS) subtypes in clinical trials and beyond.

Esophagogastric Adenocarcinoma: Is More Chemotherapy Better?

Opinion statementTwo cycles of neoadjuvant cisplatin and fluoropyrimidine (CF) and 6 cycles of perioperative CF with or without epirubicin are an evidence-based approach in operable esophageal and esophagogastric junctional adenocarcinomas. Three-drug regimens with anthracycline or taxane are associated with significantly higher tumor regression rates, with an expected increase in toxicity. In order to achieve an R0 resection and consequently a survival advantage, in selected patients having a risk of a threatened margin or incomplete resection, chemotherapy might be continued beyond 2 cycles if a response has been demonstrated. In metastatic setting, multidrug combination regimens have demonstrated a significant survival benefit when compared to single-agent regimes. A three-drug regimen should be considered for fit patients and/or when a response is required for symptom control. The expected increase in toxicity needs to be carefully considered and discussed with patients. The choice to use a taxane in first-line setting may limit the options of second-line treatment to irinotecan-containing regimens and also precludes the use of anthracyclines in the first line. For this reason, we prefer to reserve taxane-based therapy for the second-line setting.

Molecular Classification of Colon Cancer: Perspectives for Personalized Adjuvant Therapy

Although surgery for early-stage colorectal cancer (CRC) is often curative, many patients require adjuvant chemotherapy to treat micrometastatic disease and to reduce the risk of recurrence. Targeted therapies have improved outcomes for patients with metastatic disease but, in the adjuvant setting, options are limited to a fluoropyrimidine alone or in combination with oxaliplatin. There is an unmet need for new predictive biomarkers to personalise treatment in the adjuvant setting. With goals to address this gap and to better characterise disease heterogeneity, several groups including our own have identified three to six gene expression subtypes that were later consolidated into consensus molecular subtypes as part of the Colorectal Cancer Subtyping Consortium (CRCSC) effort. In this review, we discuss the differences and similarities between these subtypes and their potential prognostic and predictive values. We question whether a personalised treatment approach based on CRC subtypes might be beneficial in the adjuvant setting to improve treatment options and ultimately patient outcomes.

Formulating a surveillance strategy following surgery for oesophagogastric cancer.

153 Background: Oesophagogastric adenocarcinoma (OGA) has a poor prognosis, even for patients (pts) with operable disease. We conducted a retrospective study to assess relapse characteristics to see if these could influence follow-up strategies. Methods: We performed a retrospective review of all pts with OGA who had surgery with radical intent at the Royal Marsden between January 2001 – December 2010. Details of first relapse, including date, site, symptoms, method of relapse detection, tumour markers and treatment were recorded. Association of survival outcomes with relapse characteristics was determined by Cox regression univariate analysis. Results: 360 pts with OGA had surgery and 72.8% received neoadjuvant or peri-operative chemotherapy. After a median follow-up of 61.7 months, the median disease-free survival (DFS) was 35.6 months (95% CI 27.0 – 65.4) and median overall survival (OS) was 59.6 months (95% CI 40.7 – 81.2). 147 pts (40.8%) had disease recurrence. 51.0%, 78.9% and 91.8% of relapses occ...

Emerging treatments for advanced pancreatic cancer: clinical potential of albumin-bound paclitaxel

License. The full terms of the License are available at http://creativecommons.org/licenses/by-nc/3.0/. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. Permissions beyond the scope of the License are administered by Dove Medical Press Limited. Information on how to request permission may be found at: http://www.dovepress.com/permissions.php Gastrointestinal Cancer: Targets and Therapy 2014:4 89–101 Gastrointestinal Cancer: Targets and Therapy Dovepress