title: [Analysis of the COL1A1-PDGFB fusion gene in a case of dermatofibrosarcoma protuberans with a fibrosarcoma component].
abstract: Dermatofibrosarcoma protuberans (DFSP) is an infrequent tumor of intermediate malignancy, with little tendency to develop metastases but with a high rate of local recurrence. Cytogenetically, DFSP is characterized by a reciprocal translocation, t(17;22)(q22;q13), which is a conditioning factor in the fusion of the collagen type I alpha I gene (COL1A1) in chromosome 17q with the platelet-derived growth factor beta chain gene (PDGFB) in chromosome 22q. The fusion of these genes is variable, involving one of the 51 exons of the COL1A1 gene and exon 2 of the PDGFB gene. We present the case of a 37-year-old woman with a tumor on the arm whose histology showed a neoplastic infiltration of the subcutaneous cellular tissue made up of fusiform cells with an elongated nucleus in a storiform pattern and other more pleomorphic cells in a herringbone pattern, compatible with DFSP with a fibrosarcoma component. The molecular biology study with RT-PCR analysis of paraffin-embedded material and later sequencing showed a new fusion of exon 19 of the COL1A1 gene and exon 2 of PDGFB, supporting a diagnosis of DFSP. A study of the COL1A1-PDGFB fusion products is useful in cases where histology and immunohistochemistry are insufficient for the differential diagnosis of DFSP versus other sarcomas. It also justifies the use of new avenues of treatment with tyrosine kinase inhibitors.
authors.affiliation: Servicio de Dermatología, Instituto Valenciano de Oncología, Valencia, España. Beatriz.llombart@uv.es
authors.forename: Beatriz
authors.initials: B
authors.lastname: Llombart
authors.forename: Onofre
authors.initials: O
authors.lastname: Sanmartín
authors.forename: José A
authors.initials: JA
authors.lastname: López-Guerrero
authors.forename: Carlos
authors.initials: C
authors.lastname: Monteagudo
authors.forename: Silvia
authors.initials: S
authors.lastname: Calabuig
authors.forename: Rafael
authors.initials: R
authors.lastname: Botella
authors.forename: Eduardo
authors.initials: E
authors.lastname: Nagore
authors.forename: Celia
authors.initials: C
authors.lastname: Requena
authors.forename: Carlos
authors.initials: C
authors.lastname: Guillén
authors.forename: Antonio
authors.initials: A
authors.lastname: Cremades
authors.forename: Antonio
authors.initials: A
authors.lastname: Pellín
authors.forename: Antonio
authors.initials: A
authors.lastname: Llombart-Bosch
mesh_terms: D000328:Adult; D001132:Arm; D018223:Dermatofibrosarcoma / Q000235:genetics* / Q000473:pathology; D005260:Female; D005354:Fibrosarcoma / Q000235:genetics* / Q000473:pathology; D006801:Humans; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: C120892:COLIA1-PDGFB fusion protein, human; D015514:Oncogene Proteins, Fusion