Géraldine Perkins

Multi-purpose utility of circulating plasma DNA testing in patients with advanced cancers.

Tumor genomic instability and selective treatment pressures result in clonal disease evolution; molecular stratification for molecularly targeted drug administration requires repeated access to tumor DNA. We hypothesized that circulating plasma DNA (cpDNA) in advanced cancer patients is largely derived from tumor, has prognostic utility, and can be utilized for multiplex tumor mutation sequencing when repeat biopsy is not feasible. We utilized the Sequenom MassArray System and OncoCarta panel for somatic mutation profiling. Matched samples, acquired from the same patient but at different time points were evaluated; these comprised formalin-fixed paraffin-embedded (FFPE) archival tumor tissue (primary and/or metastatic) and cpDNA. The feasibility, sensitivity, and specificity of this high-throughput, multiplex mutation detection approach was tested utilizing specimens acquired from 105 patients with solid tumors referred for participation in Phase I trials of molecularly targeted drugs. The median cpDNA concentration was 17 ng/ml (range: 0.5–1600); this was 3-fold higher than in healthy volunteers. Moreover, higher cpDNA concentrations associated with worse overall survival; there was an overall survival (OS) hazard ratio of 2.4 (95% CI 1.4, 4.2) for each 10-fold increase in cpDNA concentration and in multivariate analyses, cpDNA concentration, albumin, and performance status remained independent predictors of OS. These data suggest that plasma DNA in these cancer patients is largely derived from tumor. We also observed high detection concordance for critical ‘hot-spot’ mutations (KRAS, BRAF, PIK3CA) in matched cpDNA and archival tumor tissue, and important differences between archival tumor and cpDNA. This multiplex sequencing assay can be utilized to detect somatic mutations from plasma in advanced cancer patients, when safe repeat tumor biopsy is not feasible and genomic analysis of archival tumor is deemed insufficient. Overall, circulating nucleic acid biomarker studies have clinically important multi-purpose utility in advanced cancer patients and further studies to pursue their incorporation into the standard of care are warranted.

Iron deficiency: From diagnosis to treatment

Iron deficiency is the most frequent cause of anaemia worldwide. It impairs quality of life, increases asthenia and can lead to clinical worsening of patients. In addition, iron deficiency has a complex mechanism whose pathologic pathway is recently becoming better understood. The discovery of hepcidin has allowed a better clarification of iron metabolism regulation. Furthermore, the ratio of concentration of soluble transferrin receptor to the log of the ferritin level, has been developed as a tool to detect iron deficiency in most situations. The cause of iron deficiency should always be sought because the underlying condition can be serious. This review will summarize the current knowledge regarding diagnostic algorithms for iron deficiency anaemia. The majority of aetiologies occur in the digestive tract, in men and postmenopausal women, and justify morphological examination of the gut. First line investigations are upper gastrointestinal endoscopy and colonoscopy, and when negative, the small bowel should be explored; newer tools such as video capsule endoscopy have also been developed. The treatment of iron deficiency is aetiological if possible and iron supplementation whether in oral or in parenteral form. New parenteral formulations are available and seem to have promising results in terms of efficacy and safety.

A Study of Hypermethylated Circulating Tumor DNA as a Universal Colorectal Cancer Biomarker

BACKGROUND Circulating tumor DNA (ctDNA) has emerged as a good candidate for tracking tumor dynamics in different cancer types, potentially avoiding repeated tumor biopsies. Many different genes can be mutated within a tumor, complicating procedures for tumor monitoring, even with highly sensitive next-generation sequencing (NGS) strategies. Droplet-based digital PCR (dPCR) is a highly sensitive and quantitative procedure, allowing detection of very low amounts of circulating tumor genetic material, but can be limited in the total number of target loci monitored. METHODS We analyzed hypermethylation of 3 genes, by use of droplet-based dPCR in different stages of colorectal cancer (CRC), to identify universal markers for tumor follow-up. RESULTS Hypermethylation of WIF1 (WNT inhibitory factor 1) and NPY (neuropeptide Y) genes was significantly higher in tumor tissue compared to normal tissue, independently of tumor stage. All tumor tissues appeared positive for one of the 2 markers. Methylated ctDNA (MetctDNA) was detected in 80% of metastatic CRC and 45% of localized CRC. For samples with detectable mutations in ctDNA, MetctDNA and mutant ctDNA (MutctDNA) fractions were correlated. During follow-up of different stage CRC patients, MetctDNA changes allowed monitoring of tumor evolution. CONCLUSIONS These results indicate that MetctDNA could be used as a universal surrogate marker for tumor follow-up in CRC patients, and monitoring MetctDNA by droplet-based dPCR could avoid the need for monitoring mutations.

Signet-ring cell carcinoma of the stomach: Impact on prognosis and specific therapeutic challenge.

While the incidence of gastric cancer has decreased worldwide in recent decades, the incidence of signet-ring cell carcinoma (SRCC) is rising. SRCC has a specific epidemiology and oncogenesis and has two forms: early gastric cancer, which can be resected endoscopically in some cases and which has a better outcome than non-SRCC, and advanced gastric cancer, which is generally thought to have a worse prognosis and lower chemosensitivity than non-SRCC. However, the prognosis of SRCC and its chemosensitivity with specific regimens are still controversial as SRCC is not specifically identified in most studies and its poor prognosis may be due to its more advanced stage. It therefore remains unclear if a specific therapeutic strategy is justified, as the benefit of perioperative chemotherapy and the value of taxane-based chemotherapy are unclear. In this review we analyze recent data on the epidemiology, oncogenesis, prognosis and specific therapeutic strategies in both early and advanced SRCC of the stomach and in hereditary diffuse gastric cancer.

Validation and utilisation of high-coverage next-generation sequencing to deliver the pharmacological audit trail.

Background:Predictive biomarker development is a key challenge for novel cancer therapeutics. We explored the feasibility of next-generation sequencing (NGS) to validate exploratory genomic biomarkers that impact phase I trial selection.Methods:We prospectively enrolled 158 patients with advanced solid tumours referred for phase I clinical trials at the Royal Marsden Hospital (October 2012 to March 2013). After fresh and/or archived tumour tissue were obtained, 93 patients remained candidates for phase I trials. Results from tumour sequencing on the Illumina MiSeq were cross-validated in 27 out of 93 patients on the Ion Torrent Personal Genome Machine (IT-PGM) blinded to results. MiSeq validation with Sequenom MassARRAY OncoCarta 1.0 (Sequenom Inc., San Diego, CA, USA) was performed in a separate cohort.Results:We found 97% concordance of mutation calls by MiSeq and IT-PGM at a variant allele frequency ⩾13% and ⩾500 × depth coverage, and 91% concordance between MiSeq and Sequenom. Common ‘actionable’ mutations involved deoxyribonucleic acid (DNA) repair (51%), RAS-RAF-MEK (35%), Wnt (26%), and PI3K-AKT-mTOR (24%) signalling. Out of 53, 29 (55%) patients participating in phase I trials were recommended based on identified actionable mutations.Conclusions:Targeted high-coverage NGS panels are a highly feasible single-centre technology well-suited to cross-platform validation, enrichment of trials with molecularly defined populations and hypothesis testing early in drug development.

Early Evaluation of Circulating Tumor DNA as Marker of Therapeutic Efficacy in Metastatic Colorectal Cancer Patients (PLACOL Study)

Purpose: Markers of chemotherapy efficacy in metastatic colorectal cancer (mCRC) are essential for optimization of treatment strategies. We evaluated the applicability of early changes in circulating tumor DNA (ctDNA) as a marker of therapeutic efficacy. Experimental Design: This prospective study enrolled consecutive patients with mCRC receiving a first- or second-line chemotherapy. CtDNA was assessed in plasma collected before the first (C0), second (C1) and/or third (C2) chemotherapy cycle, using picodroplet-digital PCR assays based either on detection of gene mutation (KRAS, BRAF, TP53) or hypermethylation (WIF1, NPY). CT scans were centrally assessed using RECIST v1.1 criteria. Multivariate analyses were adjusted on age, gender, ECOG performance status (PS), metastatic synchronicity, and treatment line. Results: Eighty-two patients with mCRC treated in first- (82.9%) or second- (17.1%) line chemotherapy were included. Patients with a high (>10 ng/mL) versus low (≤0.1 ng/mL) ctDNA concentration at C0 had a shorter overall survival (OS; 6.8 vs. 33.4 months: adjusted HR, 5.64; 95% CI, 2.5–12.6; P < 0.0001). By analyzing the evolution of the ctDNA concentration between C0 and C2 or C1 (C2or1), we classified the patients in two groups (named “good” or “bad ctDNA responders”). In multivariate analysis, patients belonging to the group called “good ctDNA responder” (n = 58) versus “bad ctDNA responder” (n = 15) had a better objective response rate (P < 0.001), and a longer median progression-free survival (8.5 vs. 2.4 months: HR, 0.19; 95% CI, 0.09–0.40; P < 0.0001) and OS (27.1 vs. 11.2 months: HR, 0.25; 95% CI, 0.11–0.57; P < 0.001). Conclusions: This study suggests that early change in ctDNA concentration is a marker of therapeutic efficacy in patients with mCRC. Clin Cancer Res; 23(18); 5416–25. ©2017 AACR.

Feasibility of Gemcitabine plus Oxaliplatin in Advanced Hepatocellular Carcinoma Patients with Child-Pugh B Cirrhosis

Purpose: Sorafenib improves survival in advanced hepatocellular carcinoma (HCC), but the demonstration of its efficacy and safety is limited to Child-Pugh A cirrhotic patients. The biweekly combination of gemcitabine and oxaliplatin (GEMOX) is safe and widely used in patients with advanced malignancies. We aimed to evaluate the feasibility of GEMOX in HCC patients with Child-Pugh B cirrhosis ineligible for sorafenib. Methods: The medical records of cirrhotic patients with advanced HCC receiving the GEMOX regimen between July 2006 and November 2011 were retrospectively reviewed. Treatment was repeated every 2 weeks until disease progression or unacceptable adverse effects occurred. The primary evaluation criterion was safety. Secondary evaluation criteria were the presence of muscle wasting (sarcopenia), response rate, progression-free survival and overall survival (OS). Results: Patients with Child-Pugh A (group A, n = 17) or Child-Pugh B cirrhosis (group B, n = 15) received a total of 169 cycles (median 4, range 1–16/patient). Eight patients in each group had sarcopenia. Common toxicities were thrombocytopenia (25 and 14 in groups A and B, respectively; p = 0.65) and peripheral neuropathy (44 and 54% in groups A and B, respectively; p = 1). Neither febrile neutropenia nor toxic death occurred. One patient in each group experienced grade 3 oesophageal varices bleeding. The response and disease control rates were 18% (95% CI 0–35.8) and 58.8% (95% CI 35.4–82.2) in group A, and 27% (95% CI 4.3–49.1) and 60.0% (95% CI 35.2–84.8) in group B. The median progression-free survival and OS did not differ between the two groups, but median OS was significantly shorter in sarcopenic patients. Conclusions: The GEMOX regimen appears feasible in HCC patients with Child-Pugh B cirrhosis and exerts anti-tumour activity. These data need to be confirmed in a prospective study.

Feasibility of gemcitabine and oxaliplatin in patients with advanced biliary tract carcinoma and a performance status of 2.

The use of gemcitabine and oxaliplatin is well documented in selected patients with advanced biliary tract carcinoma (BTC), but little is known on the feasibility of systemic treatments in patients with a performance status (PS) of 2. We retrospectively examined the medical records of consecutive BTC patients with a PS of 2 receiving gemcitabine 1000 mg/m2 plus oxaliplatin 100 mg/m2 every 2 weeks from January 2003 to December 2011 in our institution. Body composition was analysed by computed tomography scan to detect sarcopenia. The primary evaluation criterion was safety. The secondary evaluation criteria were the response rate, progression-free survival (PFS) and overall survival (OS). Twenty-eight patients (median age: 63 years, range 41–83) received a total of 175 cycles (median per patient: 6, range 2–12). Ten patients (35.7%) had sarcopenia on the pretreatment computed tomography scan. The most frequent toxicities were thrombocytopenia (grades 2–4: n=4, 14.3%), peripheral neuropathy (grades 2–3: n=9, 32.1%) and cholangitis (n=4, 14.3%). The best response was a partial response in 10.7% of patients [95% confidence interval (CI): 0–22.2] and stable disease in 42.9% of patients. The median PFS and OS were 4.6 (95% CI: 2.5–6.3) and 7.5 (95% CI: 5.2–9.5) months, respectively. The median PFS and OS were significantly longer in patients without sarcopenia: 7.0 months (95% CI: 4.4–8.0) vs. 2.2 months (95% CI: 2.0–2.5), P less than 0.01, and 10.4 months (95% CI: 7.5–11.6) vs. 4.9 months (95% CI: 3.7–5.2), P less than 0.01, respectively. In our experience, gemcitabine–oxaliplatin was feasible and induced effective palliation in PS2 patients with advanced BTC. Further studies are warranted to confirm these findings.

Diagnosis of Iron Deficiency in Inflammatory Bowel Disease by Transferrin Receptor-Ferritin Index.

AbstractIron deficiency is common in patients with inflammatory bowel disease (IBD), but can be difficult to diagnose in the presence of inflammation because ferritin is an acute phase reactant. The transferrin receptor-ferritin index (TfR-F) has a high sensitivity and specificity for iron deficiency diagnosis in chronic diseases. The diagnostic efficacy of TfR-F is little known in patients with IBD. The aim of the study was to assess the added value of TfR-F to iron deficiency diagnosis in a prospective cohort of patients with IBD.Consecutive IBD patients were prospectively enrolled. Patients were excluded in case of blood transfusion, iron supplementation, or lack of consent. IBD activity was assessed on markers of inflammation (C-reactive protein, endoscopy, fecal calprotectin). Hemoglobin, ferritin, vitamin B9 and B12, Lactate dehydrogenase, haptoglobin, and soluble transferrin receptor (sTfR) were assayed. TfR-F was calculated as the ratio sTfR/log ferritin. Iron deficiency was defined by ferritin <30 ng/mL or TfR-F >2 in the presence of inflammation.One-hundred fifty patients with median age 38 years (16–78) and Crohn disease (n = 105), ulcerative colitis (n = 43), or unclassified colitis (n = 2) were included. Active disease was identified in 45.3%. Anemia was diagnosed in 28%. Thirty-six patients (24%) had ferritin <30 ng/mL. Thirty-two patients (21.3%) had ferritin levels from 30 to 100 ng/ml and inflammation: 2 had vitamin B12 deficiency excluding TfR-F analysis, 13 of 30 (43.3%) had TfR-F >2. Overall, iron deficiency was diagnosed in 32.7% of the patients.TfR-F in addition to ferritin <30 ng/mL criterion increased by 36% diagnosis rates of iron deficiency. TfR-F appeared as a useful biomarker that could help physicians to diagnose true iron deficiency in patients with active IBD.

Expression of pEGFR and pAKT as response-predictive biomarkers for RAS wild-type patients to anti-EGFR monoclonal antibodies in metastatic colorectal cancers.

Background:RAS wild-type (RASw/t) tumours have been associated with better outcomes in patients with metastatic colorectal cancer (mCRC) treated with anti-EGFR monoclonal antibodies (mAb). We investigated the expression of EGFR downstream proteins under their active phosphorylated forms as potential markers in response to these patients.Methods:One-hundred tumour samples were collected from patients with mCRC refractory to FOLFOX and/or FOLFIRI and treated by a combination of chemotherapy with anti-EGFR mAb. The outcomes were measured on response evaluation criteria in solid tumour (RECIST), progression-free survival (PFS) and overall survival (OS). All samples were assessed for RAS and BRAF mutations, and the key phosphorylated proteins of EGFR downstream signalling were quantitatively analysed using the BioPlex Protein array.Results:Among the 60 RASw/t patients, 45.0% achieved a complete or partial response when treated with anti-EGFR mAb. Expression of pAKT, pERK1/2 and pMEK1 was significantly lower in RASw/t patients (P=0.0246; P=0.004; P=0.0110, respectively). The response rate was significantly higher for RASw/t patients who express pEGFR and pAKT (P=0.0258; P=0.0277, respectively).Conclusions:Overexpression of pEGFR and pAKT may predict the response rate in RASw/t patients treated with anti-EGFR mAb. On the basis of our results, we hypothesise that the association of anti-EGFR mAb and anti-AKT therapies could be of interest.