Camille Tlemsani

Sarcopenia and body mass index predict sunitinib-induced early dose-limiting toxicities in renal cancer patients

Background:Little is known on factors predicting sunitinib toxicity. Recently, the condition of low muscle mass, named sarcopenia, was identified as a significant predictor of toxicity in metastatic renal cell cancer (mRCC) patients treated with sorafenib. We investigated whether sarcopenia could predict early dose-limiting toxicities (DLTs) occurrence in mRCC patients treated with sunitinib.Methods:Consecutive mRCC patients treated with sunitinib were retrospectively reviewed. A DLT was defined as any toxicity leading to dose reduction or treatment discontinuation. Body composition was evaluated using CT scan obtained within 1 month before treatment initiation.Results:Among 61 patients eligible for analysis, 52.5% were sarcopenic and 32.8% had both sarcopenia and a body mass index (BMI)<25 kg m−2. Eighteen patients (29.5%) experienced a DLT during the first cycle. Sarcopenic patients with a BMI<25 kg m−2 experienced more DLTs (P=0.01; odds ratio=4.1; 95% CI: (1.3–13.3)), more cumulative grade 2 or 3 toxicities (P=0.008), more grade 3 toxicities (P=0.04) and more acute vascular toxicities (P=0.009).Conclusion:Patients with sarcopenia and a BMI<25 kg m−2 experienced significantly more DLTs during the first cycle of treatment.

Posterior reversible encephalopathy syndrome induced by anti-VEGF agents

Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological entity that may occur in patients receiving anti-vascular endothelial growth factor (VEGF) agents such as bevacizumab and tyrosine kinase inhibitors. Little is known about the characteristics of patients at risk for PRES under anti-VEGF agents. We carried out a comprehensive review of reports documenting the occurrence of PRES in patients receiving anti-VEGF agents. Twenty-six patients are described with a majority of females (73.1%). Almost a third of patients had a past history of hypertension. The most common symptoms included headache, visual disturbance and seizure. A vast majority of patients had hypertension at the diagnosis of PRES, and proteinuria was detectable each time it was investigated. Neurological outcome was favorable in all cases with a symptomatic treatment including blood pressure control. The risk of PRES is increased when blood pressure is poorly controlled and when proteinuria is detectable. The clinical course appears favorable with a symptomatic treatment. PRES is a potentially severe but manageable toxicity of anti-VEGF agents.

Effect of glucuronidation on transport and tissue accumulation of tyrosine kinase inhibitors: consequences for the clinical management of sorafenib and regorafenib

Introduction: UDP-glucuronosyltransferases (UGTs) are a multigenic family of enzymes responsible for the glucuronidation reaction. Many therapeutic classes of drugs used in solid tumors are UGT substrates, including cancer therapies. Areas covered: This article describes the tyrosine kinase inhibitors (TKIs) undergoing hepatic glucuronidation; its effect on transport and tissue accumulation and the clinical consequences of this particular metabolism. A PubMed search concerning the pharmacokinetics of the TKIs was performed. All are extensively metabolized by CYP450. Two TKIs, sorafenib and regorafenib, also have a major UGT-mediated metabolism and were therefore studied. Expert opinion: The prescription of the same dose of sorafenib and regorafenib for all patients may be inappropriate since at each enzymatic step of this multistep metabolism inter-individual fluctuations exist. Having a non-exclusive CYP-mediated route of metabolism may reduce the risk of variability in drug exposure when CYP3A4 substrates are concomitantly given. Several clinical consequences derive from this pharmacokinetic particularity of sorafenib and regorafenib. Since no clear difference distinguishes TKIs in efficacy in large randomized trials, the differences for the clinical management of their toxicity is a critical aspect.

Clinical pharmacology, drug-drug interactions and safety of pazopanib: a review.

ABSTRACT Introduction: In the past decade, treatment options for metastatic renal cell carcinoma and soft-tissue sarcoma have expanded. Pazopanib was discovered during the screening of compounds that suppressed vascular endothelial growth factor receptor-2 (VEGFR-2). As other tyrosine kinase inhibitors (TKI), pazopanib is not totally specific for one target since it also inhibits stem-cell factor receptor (cKIT), platelet-derived growth factor receptors (PDGFRα, β), VEGFR-1 and −3. Areas covered: Clinical pharmacology, drug-drug interactions and safety data published on pazopanib, between January 2006 and April 2016, are reviewed. Expert opinion: This new therapy has been shown to improve progression-free survival compared with previous approaches, in renal cell cancer and soft-tissue sarcoma. However, some specific sub-populations, such as elderly patients, patients with brain metastases or with Eastern Cooperative Oncology Group Performance Status (ECOG PS) 2 or comorbidities, are poorly represented in pivotal pazopanib phase III studies. Pazopanib meets criteria defining therapies as candidates for therapeutic drug monitoring: large intra- and inter-patient pharmacokinetic variability, potential pharmacokinetic drug-drug interactions, pharmacokinetic/pharmacodynamic relationship and narrow therapeutic index. Knowledge of predictors that can be used to guide dosing regimens in the target population and in special populations needs to be improved.

SETD2 and DNMT3A screen in the Sotos-like syndrome French cohort

Background Heterozygous NSD1 mutations were identified in 60%–90% of patients with Sotos syndrome. Recently, mutations of the SETD2 and DNMT3A genes were identified in patients exhibiting only some Sotos syndrome features. Both NSD1 and SETD2 genes encode epigenetic ‘writer’ proteins that catalyse methylation of histone 3 lysine 36 (H3K36me). The DNMT3A gene encodes an epigenetic ‘reader’ protein of the H3K36me chromatin mark. Methods We aimed at confirming the implication of DNMT3A and SETD2 mutations in an overgrowth phenotype, through a comprehensive targeted-next generation sequencing (NGS) screening in 210 well-phenotyped index cases with a Sotos-like phenotype and no NSD1 mutation, from a French cohort. Results Six unreported heterozygous likely pathogenic variants in DNMT3A were identified in seven patients: two nonsense variants and four de novo missense variants. One de novo unreported heterozygous frameshift variant was identified in SETD2 in one patient. All the four DNMT3A missense variants affected DNMT3A functional domains, suggesting a potential deleterious impact. DNMT3A-mutated index cases shared similar clinical features including overgrowth phenotype characterised by postnatal tall stature (≥+2SD), macrocephaly (≥+2SD), overweight or obesity at older age, intellectual deficiency and minor facial features. The phenotype associated with SETD2 mutations remains to be described more precisely. The p.Arg882Cys missense de novo constitutional DNMT3A variant found in two patients is the most frequent DNMT3A somatic mutation in acute leukaemia. Conclusions Our results illustrate the power of targeted NGS to identify rare disease-causing variants. These observations provided evidence for a unifying mechanism (disruption of apposition and reading of the epigenetic chromatin mark H3K36me) that causes an overgrowth syndrome phenotype. Further studies are needed in order to assess the role of SETD2 and DNMT3A in intellectual deficiency without overgrowth.

Investigational therapies up to Phase II which target PDGF receptors: potential anti-cancer therapeutics

Introduction: The platelet-derived growth factor receptor (PDGFR) pathway has important functions in cell growth and, by overexpression or mutation, could also be a driver for tumor development. Moreover, PDGFR is expressed in a tumoral microenvironment and could promote tumorigenesis. With these biological considerations, the PDGFR pathway could be an interesting target for therapeutics. Currently, there are many molecules under development that target the PDGFR pathway in different types of cancer. Areas covered: In this review, the authors report the different molecules under development, as well as those approved albeit briefly, which inhibit the PDGFR pathway. Furthermore, the authors summarize their specificities, their toxicities, and their development. Expert opinion: Currently, most PDGFR kinase inhibitors are multikinase inhibitors and therefore do not simply target the PDGFR pathway. The development of more specific PDGFR inhibitors could improve drug efficacy. Moreover, selecting tumors harboring mutations or amplifications of PDGFR could improve outcomes associated with the use of these molecules. The authors believe that new technologies, such as kinome arrays or pharmacologic assays, could be of benefit to understanding resistance mechanisms and develop more selective PDGFR inhibitors.

Hereditary diffuse gastric cancer syndrome: improved performances of the 2015 testing criteria for the identification of probands with a CDH1 germline mutation

The international, consensus testing criteria for CDH1 germline mutations were recently revised in order to increase their performances, particularly their sensitivity. It is paramount to identify a high proportion of actual mutation carriers, as finding a mutation in a proband and subsequently in some of his relatives allows for risk-reducing recommendations regarding diffuse gastric cancer (DGC) and lobular breast cancer (LBC). We collected data on all French probands tested for CDH1 in a retrospective study on the hereditary DGC syndrome (HDGC). Out of 627 probands, 52 were carriers. We compared the new, 2015 version of these criteria to the 2010 version, and showed that both the sensitivity and the Youden index ( J ), an index that estimates the criteria discriminating power, increased. CDH1 is a tumour suppressor gene located on chromosome 16q22. It codes for the E-cadherin adhesion protein. Monoallelic germline mutations in CDH1 cause HDGC, in which carriers have a high lifetime risk of DGC (also called signet ring cell gastric cancer), and LBC (reviewed in ref. 1). In clinical practice, mutations are first identified in a proband with a personal history of DGC and/or LBC, and adult relatives are subsequently tested to see whether they also carry the mutation. Asymptomatic carriers are then advised to undergo risk-reducing gastrectomy, and for women annual breast cancer screening using MRI. The International Gastric Cancer Linkage Consortium defined clinical criteria warranting CDH1 germline testing in a proband. The criteria were first published in 1999 and then updated in 2010.2 ,3 A new 2015 version is being published in this issue of the Journal of Medical Genetics …

Inhibiteurs de tyrosine kinase ciblant l’angiogenèse et sujets âgés : tolérance, évaluation pré-thérapeutique et gestion des effets indésirables

Angiogenesis inhibition is a major antitumor strategy that has emerged during the last decade. Oral tyrosine kinase inhibitors (TKI) targeting the VEGF receptor, including sunitinib, sorafenib, axitinib, regorafenib, pazopanib, and vandetanib reduce tumor growth and metastasis. These agents are approved for the treatment of metastatic diseases in first or second-line. They display a narrow therapeutic index. However, data in the elderly and/or in patients with multiple illnesses remain scarce. This population is classically excluded from clinical trials. The aim of this review is to provide an overview of existing literature regarding antiangiogenic TKI tolerance in the elderly (>70 years old). We also highlight key points of the pre-therapeutic evaluation and summarize the management of common toxicities.

SynthèseInhibiteurs de tyrosine kinase ciblant l’angiogenèse et sujets âgés : tolérance, évaluation pré-thérapeutique et gestion des effets indésirablesTyrosine kinase inhibiting the VEGF pathway and elderly people: Tolerance, pre-treatment assessment and side effects management

Angiogenesis inhibition is a major antitumor strategy that has emerged during the last decade. Oral tyrosine kinase inhibitors (TKI) targeting the VEGF receptor, including sunitinib, sorafenib, axitinib, regorafenib, pazopanib, and vandetanib reduce tumor growth and metastasis. These agents are approved for the treatment of metastatic diseases in first or second-line. They display a narrow therapeutic index. However, data in the elderly and/or in patients with multiple illnesses remain scarce. This population is classically excluded from clinical trials. The aim of this review is to provide an overview of existing literature regarding antiangiogenic TKI tolerance in the elderly (>70 years old). We also highlight key points of the pre-therapeutic evaluation and summarize the management of common toxicities.

BRCA2 Loss-of-Function and High Sensitivity to Cisplatin-Based Chemotherapy in a Patient With a Pleomorphic Soft Tissue Sarcoma: Effect of Genomic Medicine

&NA; We report the case of a patient with a BRCA2 germline mutation who developed a localized pleomorphic soft tissue sarcoma of the leg with poor prognostic features. BRCA2 germline mutations were not previously reported to be associated with pleomorphic sarcoma. BRCA2 loss‐of‐heterozygosity was found in the tumor, resulting in a complete BRCA2 loss‐of‐function. BRCA2 deficiency is associated with sensitivity to cisplatin‐based chemotherapy in breast and ovarian cancer patients. We used a cisplatin‐based chemotherapy. A rapid major partial response was obtained, which allowed a curative and conservative surgical resection of the sarcoma followed by adjuvant irradiation. This case illustrates that sarcoma patients may present unexpected but targetable genetic abnormalities and that BRCA2 loss‐of‐function may be targetable in sarcoma as it is associated with enhanced sensitivity to cisplatin. Our observation emphasizes the input of genomic medicine in clinical practice, its importance for treatment decisions, and the overlap between constitutional and somatic genetics.