Translocations in sarcomas Klinisch belang van chromosomale translocatie detectie in sarcomen Judith V.M.G. Bovée, M.D., Ph.D. Department of Pathology Leiden University Medical Center RNA binding DNA binding Classification of bone and soft tissue tumors Bone and soft tissue tumours are difficult for pathologists: Relatively rare >40 entities Considerable morphological overlap Entities differ widely in treatment and outcome Increasing knowledge on genetic background of tumours 2002 WHO classification on bone and soft tissue tumours Relevance of translocations in sarcomas 1. Clues about the pathogenesis 2. Classification of sarcomas 3. Usefull in differential diagnosis 4. Detection minimal residual disease? 5. Prediction of outcome? 6. Identify targets for treatment Diagnosis of soft tissue tumours Techniques for translocation detection Classifying soft tissue tumours: H&E Immunohistochemistry Molecular diagnostics 15-20% of mesenchymal tumours carry translocations Only in specific tumour types: Cornerstone of diagnosis Ewing sarcoma, myxoid liposarcoma, synoviosarcoma up to 100% Absent in osteosarcoma, chondrosarcoma, leiomyosarcoma Conventional cytogenetics RT-PCR FISH (immunohistochemistry) (fresh tissue) (frozen tissue, paraffin) (paraffin material, not decalcified!) 1
Conventional karyotyping EWSR1 translocation EWSR1 FLI1 ERG ETV1 E1AF FEV WT1 NR4A3 ATF1 CREB1 GADD153 Ewing sarcoma / PNET Desmoplastic small round cell tumour Extraskeletal myxoid chondrosarcoma Angiomatoid FH Myxoid liposarcoma RT-PCR Small blue round cell tumours; differential diagnosis Ewing sarcoma / PNET Rhabdomyosarcoma Neuroblastoma Non Hodgkin Lymfoma / leukemia Small cell osteosarcoma Mesenchymal chondrosarcoma desmin, MYF4 - CD45 osteoid (ALP) cartilage Poorly differentiated monofasic synoviosarcoma FISH analysis Ewing versus poorly diff synovio: immunohistochemistry normal t(11;22) 11 22 11 der11 der22 22 HE Ewing 99% Synovio (poorly diff) 66% HE keratin 8% 67% S100 17% 25% ker t(11;22) EWSR1 break t(x;18) SYT break ker 2
Ewing sarcoma Ewing sarcoma / PNET specific translocations t(11;22)(q24;q12) t(21;22)(q22;q12) t(7;22)(q22;q12) t(17;22)(q12;q12) t(2;22)(q33;q12) EWS-FLI1 85% EWS-ERG ERG 10% EWS-ETV1 ETV1 <1% EWS-ETV4 ETV4 <1% EWS-FEV <1% t(16;21)(p11;q22) FUS-ERG De Alava et al. 2000 J Clin Oncol 18:204-213 213 EWS-ETS ETS fusionproteins t(11;22)(q24;q12) Prognostic value of EWSR1-FLI1 fusion type? Different variants: Type 1: 60% Type 2: Type 1 associated with better prognosis: 25%? De Alava et al. 2000 J Clin Oncol 18:204-213 De Alava JCO 1998 Ewing sarcoma / PNET White, young persons (80% < 20 jaar) Male > female In bone and soft tissue Resection, with chemotherapy (incl( pre-operative), radiotherapy 5 years survival 50% Spindle cell tumours; differential diagnosis Monophasic synovial sarcoma Malignant peripheral nerve sheath tumour Fibrosarcoma Leiomyosarcoma HE, vim Muscle markers S100, HMB45, EWSR1 rearrangement 3
Synoviosarcoma vs. MPNST; immunohistochemistry SYT-SSX fusion; prognostic value? EMA Synovial sarcoma 78% MPNST 17% Association fusion type and morphology: Monophasic: : mostly SYT-SSX2 SSX2 Biphasic: mostly SYT-SSX1 SSX1 SYT-SSX1 SSX1 associated with early relapse keratine 66% 67% 100% 15% Ladanyi et al. 2002 Cancer Res Canter et al. 2008 Clin Cancer Res Bcl2 94% 28% S100 25% 64% t(x;18) SYT break No specific changes Other groups: no association fusion type and prognosis (n=141 and n=91) Synovial sarcoma All ages, peak 10-35 yrs Soft tissue: 60% in lower extremity (esp( thigh) High grade sarcoma 5 year survival 50% 10 year survival 20-30% Morphology Biphasic: spindle and epithelial cell component Monophasic: only spindle (or epithelial) cells Aneurysmal Bone Cyst t(16;17)(q22;p13) t(1;17)(p34.1 34.3;p13) 34.3;p13) t(3;17)(q21;p13) t(9;17)(q22;p13) t(17;17)(q12;p13) CDH11-USP6 TRAP150-USP6 ZNF9-USP6 OMD-USP6 COL1A1-USP6 oncogenic activation USP6 gene vs. melanoma Mod Pathol 2000; 13:1253-1263 melanoma S100 HMB45 vimentin keratin - - t(12;22) EWSR1 break 4
vs. melanoma Dermatofibrosarcoma protuberans A A soft tissue sarcoma of young adults with melanocytic differentiation, typically involving tendons and aponeuroses Equal male-female distribution, 5-855 years (median 30 yrs.) extremities Deep location Variable outcome, prognosis usually bad, recurrence sometimes after 10 years Dermatofibrosarcoma Protuberans (DFSP) Poorly recognized by clinicians Adults 20-50 years, male predominance Duration prior to diagnosis > 5 year; long clinical course Location: Trunk, head & neck, proximal extremity Regarded a superficial low-grade sarcoma Significant risk of local recurrence (<3 yrs) Wide local excision (2-3 cm): 18% Superficial / incomplete excision: 43% Rarely metastases ; genetics DFSP; genetics t(12;22)(q13;q12) t(2;22)(q32;q12) ATF1-EWSR1 EWSR1-CREB1 der(22)t(17;22)(q22;q13) COL1A1-PDGFB Angiomatoid fibrous histiocytoma t(2;22)(q32;q12) EWSR1-CREB1 t(12;22)(q13;q12) EWSR1-ATF1 t(12;16)(q13;p11) FUS-ATF1 5
Glivec (STI571) Pre-glivec Glivec PDGFR Bcr-abl KIT ATP binds to kinase portion of receptor Cell membrane Blocks ATP binding Signal Transduction Pathways Activated Nucleus Signal Transduction Pathways Inhibited Conclusion Detection of translocations in sarcomas is relevant for: 1. Clues about the pathogenesis 2. Classification of sarcomas 3. Usefull in differential diagnosis 4. Detection minimal residual disease? 5. Prediction of outcome? 6. Identify targets for treatment 6