de DUVE INSTITUTE SARCOMAS and RHABDOID TUMORS INTERUNIVERSITY CERTIFICATE IN HUMAN GENETICS Université catholique de Louvain Brussels,19/02/2016 Professor Hélène Antoine-Poirel, MD, PhD Center for Human Genetics
Sarcomas I -Introduction II Specific translocation III- Simple genomic amplification IV- Complex& specific genetic anomalies V Activating mutations Rhabdoidtumors VI Inactivating mutations
SARCOMAS I. Introduction Malignant tumour of the connective tissue
SARCOMAS I. Introduction Characteristics 1-2% cancers Incidence : 6/100 000 hab/ yr Localisation : Soft Tissue (60%) Limb, trunk, abdomen, head& neck (Liposarcomas, rhabdomyosarcomas, poorly differentiated sarcomas, ) Viscera(30%) Digestive tract (GIST) Uterus (leiomyosarcoma) Other viscera Bone(10%) Limbbones (osteosarcomas, Ewing) Spine, pelvis (chondrosarcoma)
SARCOMAS I. Introduction 2012 WHO Classification Phenotypic characteristics: Morphology Immunohistochemistry Genetic anomalies : Specific translocations : 10-15% Simple genomic amplification : 10-15% Complex& non specific genetic anomalies : 50-60% Activating mutations : 20%
SARCOMAS II. Sarcomas with specific translocation 15-20% of soft tissue sarcomas Young patient Frequently aggressive tumors Small monomorphic cells
SARCOMAS II. Sarcomas with specific translocation
SARCOMAS II. Sarcoma with specific translocation Ex : Ewing Sarcoma Child/young adult Bone tumors(> Soft tissue in adult) Small round bluecellsarcoma, withvaryingdegreesof neurectodermal differentiation, CD99+ CD99 48,XY,+8,t(11;22)(q24;q12),+12[5]
SARCOMAS II. Sarcoma with specific translocation Ex : Ewing Sarcoma Ewing sarcoma/pnet FLI-1 (11q24) EWSR1 (22q12) Chimeric protein neo-oncogene with transforming properties
SARCOMAS II. Sarcoma with specific translocation Ex : Ewing Sarcoma Ewing sarcoma/pnet FLI-1 (11q24) 85% ERG (21q22) 10% FEV (2q33) ETV1 (7p22) E1AF/ETV4 (17q12) bone (soft tissue) soft tissue soft tissue EWSR1 (22q12) Other partner genes of EWSR1 in the Ewing sarcoma : ETS family of transcription factors ~ similar functional consequences
SARCOMAS II. Sarcoma with specific translocation Ex : Ewing Sarcoma Spectre of lesions initially reported separatly EWSR1 fusion gene Ewing sarcoma Askin tumor(chest wall) Extra-skeletic Ewing sarcoma Peripheral neuroepithelioma Peripheral primitive NeuroEctodermal Tumor/ Ewing Sarcoma Family (PNET/ESFT) variation in the level of neurectodermal differentiation undifferentiated form : differentiated form : Ewing sarcoma peripheral neuroepithelioma Cellof origin: neural crestcells?
SARCOMAS II. Sarcoma with specific translocation Ex : Ewing Sarcoma : prognosis No prognostic impact of the different fusion transcripts (RT-PCR) EF1 : EWSR1-FLI1 type 1 EF2 : EWSR1-FLI1 type 2 EE : EWSR1-ERG EFX : EWSR1-Other Le Deley M et al. JCO 2010
SARCOMAS II. Sarcoma with specific translocation Ex : Ewing Sarcoma : Minimal Disseminated Disease Prognostic significance of bone marrow (BM) micrometastasis and circulating tumor cells (PB), especially in clinically localized tumors All patients Localized tumors Schleiermacher G et al. JCO 2003
SARCOMAS II. Sarcoma with specific translocation Differential diagnosis of tumours with EWSR1 Rgt EWSR1 (22q12) Ewing sarcoma/pnet Ewing-like sarcoma/ undifferentiated small round cells sarcoma Small round cell sarcoma Desmoplastic small round cell tumour Extraskeletal myxoid chondrosarcoma Clear cell soft tissue sarcoma HELP! Primary pulmonary myxoid sarcoma Small cell osteosarcoma Myxoid liposarcoma Embryonal rhabdomyosarcoma Angiosarcoma Low-grade fibromyxoid sarcoma Sclerosing epithelioid sarcoma Mucoepidermoid carcinoma of the salivary glands Myoepithelioma / Soft tissue myoepithelial carcinoma Hyalinising clear cell carcinoma of salivary gland Acute lymphoblastic leukemia Mesothelioma Hydradenoma of the skin Angiomatoid fibrous histiocytoma Hemangioma of the bone FLI-1 (11q24) 85% ERG (21q22) 10% FEV (2q33) ETV1 (7p22) ETV4 (17q12) SP3 (2q31) NFATC2 (20q13) CIZ/NMP4 (17p13) VQCRH (1p34) PATZ1 (22q12) SMARCA5 (4q31) POU5F1 (6p21) WT1 (11p13) NR4A3 (9q22) CREB1 (2q33) ATF1 (12q13) DDIT3 (12q13) DUX4 (4q35) CREB3L1 (11p11) CREB3L2 (7q32-34) PBX1(1q23) ZNF444 (19q13) PBX3 (9q33) KLF17(1p34) ZNF384 (12p12) YY1 (14q23) NFATC1 (18q23)
SARCOMAS III. Sarcoma with simple genomic amplification Well differentiated / Dedifferentiated liposarcoma Atypical lipomatous tumour/ Well differentiated liposarcoma 2 different morphological aspects Dedifferentiated liposarcoma 10-15 % sarcomas Location : deep limbs, retro-peritoneal(60% sarcomas) Same genomic alteration
SARCOMAS III. Sarcoma with simple genomic amplification Well differentiated / Dedifferentiated liposarcoma Giant chromosome with HSR / Rings MDM2/12q14.3q15 amplification (+- CDK4 : 90%) MDM2/CEN12 MDM2 TP53.. G1 M S G2
SARCOMAS IV. Complex and non specific genetic alterations Osteosarcomas Most common primary high-grade sarcoma of the skeleton Bimodal distribution : children, older adults Complex aneuploid karyotypes Multiple numerical& structural chromosomal aberrations Amplification 6p (40-50%), 8q /MYC (45-55%) RB / 13q14 inactivation (35%) * TP53 / 17p13 inactivation (40%) ** Amplification 12q / MDM2 (10%) = low grade central osteosarcoma Deletion CDKN2A / 9p21 (15%) Transition lowgrade to high grade : polyploidy with structural alterations Inherited predisposition: * Hereditary Retinoblastoma(RB/13q14) ** Li-Fraumeni syndrome (TP53/17p13)
SARCOMAS IV. Complex and non specific genetic alterations Poorly differentiated sarcomas Adult> 50 yr Frequently«pleomorphic» Aggressive tumors, metastasis(50%) Transition lowgrade to high grade : polyploidy with structural alterations
SARCOMAS V. Activating mutations Gastro-intestinal tumour (GIST) Most common mesenchymal tumor in the gastrointestinal tract Mutually exclusive mutations in KIT or PDGFRA genes KIT (89%) PDGFRA (5%) Exon 9 : 18% Exon 11 : 67% Exon 13-14 : 2% Exon 17-18 : 2% Exon 12 : 1% Exon 18 : 4% Constitutive activation of the tyrosine kinase receptors Targeted treatment (Tyrosin kinase inhibitor Imatinib / Glivec) : adjuvant to surgery
MALIGNANT RHABDOID TUMORS VI. Inactivation mutations Recent & expanding entity 1978 : malignant rhabdoidtumors = separate morphological entity of renal tumours( Wilms tumor) close histological resemblance to rhabdomyoblasts(later not confirmed) 1994 : extrarenallocations : central nervous system (CNS), soft tissue Difficult classification : high variation in the histologic and immunologic characteristics variable rhabdoidcell component (hallmark cells) : few isolated to ~100% tumor spectrum extended to choroid plexus carcinoma, schwannomatosis, cribriform neuroepithelial tumor of the ventricle
MALIGNANT RHABDOID TUMORS VI. Inactivation mutations SWI/SNF complex 1998 : bi-allelicinactivation of SMARCB1/22q11 chromatin remodeling complex (SWI/SNF) 5% rhabdoid tumours: no SMARCB1 mutations 2010 : bi-allelic inactivation of SMARCA4/19p13 Remarkably stable genome : Xiaofeng Wang et al. Clin Cancer Res 2014 Paucity of other additional / recurrent genetic aberrations lowest rate of base variations reported in all sequenced cancer types
MALIGNANT RHABDOID TUMORS VI. Inactivation mutations Underestimated entity crucial to diagnose Early age of onset (< 3 yr-old), but also adult patients Highly aggressive High metastatic potential, poor survival rates : ~30% at 1 yr Prognostic factors: tumor stage, age at presentation No correlation genotype- phenotype Inherited predisposition Germline mutations in SMARCB1 ~35 50% of children with rhabdoid tumours higher frequency (up to 60%) in younger children (< 6months at diagnosis) more extensive disease, multi-site disease Germline mutations in SMARCA4:~50%? worse prognosis? The majority of germline mutations appear de novo Gonadal mosaicism may account for familial cases with incomplete penetrance In practice : 1. Screening by IHC on tumor : SMARCB1/INI1 or SMARCA4/BRG1 loss of expression? 2. Genetic analysis on tumoral DNA : sequencing + MLPA bi-allelic aberration? 3. Genetic analysis on blood DNA germline mutation?
MALIGNANT RHABDOID TUMORS VI. Inactivation mutations Inactivation mutation in adult tumors (mainly somatic) : SMARCB1 : epithelioid sarcomas, epithelioid malignant peripheral nerve sheath tumours, extraskeletalmyxoidcarcinoma, renal medullary carcinoma, myoepithelial carcinoma, chordoma, meningioma, SMARCA4 : small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) (2014) (somatic & germline mutations) Enigmatic tumour new category of 'SMARCA4-deficient thoracic sarcomas'(2015) Cellof origin? 2 possible scenarii of pathogenesis of SMARCB1-deficient neoplasia: 1/ primarygeneticeventin (yetunidentified) progenitorcellsexisting only during fetal development Children, few genomic mutations, highly reproducible diagnosis = «rhabdoid tumor» 2/ secondarygeneticeventin epithelialorgans: shift froma differentiatedcarcinomato a predominantly undifferentiated«rhabdoid» phenotype = «rhabdoid carcinomas»: Adults, complex pattern of genomic mutations = «SMARCB1-deficient tumor»
GENETICS OF ACQUIRED CANCERS : CONCLUSION Better understanding of oncogenesis Useful for the clinical management of patients : Diagnosis Prognosis MDD, MRD Treatment NGS : Intra-tumoral heterogeneity New prognostic biomarkers New therapeutic targets
Merci! de DUVE INSTITUTE helene.antoine-poirel@uclouvain.be