title: 12q amplification defines a subtype of extraskeletal osteosarcoma with good prognosis that is the soft tissue homologue of parosteal osteosarcoma.
abstract: Extraskeletal osteosarcomas are rare tumors with neoplastic cells synthesizing bone, usually associated with poor prognosis. We present the case of a 40-year-old man with an extraskeletal osteosarcoma that was treated by surgery and adjuvant radiotherapy. Thirteen years after the diagnosis, he remains disease-free, without any recurrences or metastases. Histopathological analysis favored the diagnosis of chondroblastic extraskeletal osteosarcoma grade II. G-banding, comparative genomic hybridization (CGH), and real-time PCR for the MDM2 and CDK4 genes were performed to describe the genetic profile of this tumor and revealed aberrations that are common findings of parosteal osteosarcomas. Ring chromosomes, giant marker chromosomes, and a telomeric association were found with G-banding. CGH revealed that 12q was amplified in the ring and giant markers identified by G-banding. Real-time PCR for MDM2 and CDK4 confirmed the amplification of these genes located in 12q. Our findings suggest that a variant of extraskeletal osteosarcoma, which is genotypically similar to parosteal osteosarcoma, exists and is associated with good prognosis.
authors: Department of Genetics, Saint Savvas Hospital, Athens, Greece. tassoskyr@gmail.com
authors: Anastasios I
authors: AI
authors: Kyriazoglou
authors: Joana
authors: J
authors: Vieira
authors: Efthimios
authors: E
authors: Dimitriadis
authors: Niki
authors: N
authors: Arnogiannaki
authors: Manuel R
authors: MR
authors: Teixeira
authors: Nikos
authors: N
authors: Pandis
mesh_terms: D000328:Adult; D001859:Bone Neoplasms / Q000235:genetics / Q000532:radiotherapy / Q000601:surgery; D002871:Chromosome Banding; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics*; D055028:Comparative Genomic Hybridization; D051358:Cyclin-Dependent Kinase 4 / Q000235:genetics*; D005784:Gene Amplification; D006801:Humans; D008297:Male; D012516:Osteosarcoma / Q000235:genetics* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D011379:Prognosis; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics*; D018714:Radiotherapy, Adjuvant; D060888:Real-Time Polymerase Chain Reaction; D012303:Ring Chromosomes; D016615:Telomere / Q000235:genetics
chemical_list: C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; C495900:CDK4 protein, human; D051358:Cyclin-Dependent Kinase 4