Dermatofibrosarcoma protuberans: clinical, pathological, and genetic (COL1A1‐PDGFB ) study with therapeutic implications

Abstract

The COL1A1-PDGFB fusion was present in all histological subtypes of DFSP, but not all cases expressed the fusion transcript. No association was observed between different COL1A1 breakpoints and clinicopathological parameters. Imatinib mesylate can be useful in locally advanced tumours and metastases.

Molecular diagnosis of dermatofibrosarcoma protuberans: A comparison between reverse transcriptase‐polymerase chain reaction and fluorescence in situ hybridization methodologies

“…Detection of the COL1A1/PDGFB transcript varied from 74 to 96% (Maire et al, 2002;Gokden et al, 2003;Terrier-Lacombe et al, 2003;Llombart et al, 2009;Patel et al, 2008). In the present study, in which we include 63 cases previously published (Llombart et al, accepted for publication), we detected the COL1A1/PDGFB transcript in 80% of DFSP.…”

“…RNA was extracted using 1 ml of Trizol Reagent (Invitrogene, Carlsbad, CA) following the manufacturer's instructions. RT-PCR was carried out as previously described (Llombart et al, 2009). …”

“…This phenomenon could be explained by several factors which may be due to the integrity and quality of the total RNA: (i) the retrospective nature of the study: many samples had been obtained from more than 20 years ago; and (ii) the multi-institutional collections of the cases: samples from four different centres have been used in the study and the different procedures in sample processing (fixation, time to fixation, temperature for paraffin-embedding and storing conditions) could probably explain our data. Although it has been demonstrated that the use of frozen tissue for the RT-PCR could improve the success rate of this technique (Llombart et al, 2009), this material is not always available in a routine pathology laboratory.…”

Identification of t(17;22)(q22;q13) (COL1A1/PDGFB) in dermatofibrosarcoma protuberans by fluorescence in situ hybridization in paraffin-embedded tissue microarrays

“…Different results using RT-PCR amplification techniques have been reported. A recent work including 20 cases of DFSP using frozen tissue samples detected 16 positive cases from the 18 (89%) in which RNA could be obtained [23]. Other studies using paraffin-embedded tissue showed variable results from 74% to 96% [17,24,25] of positive cases.…”

Current approaches to cutaneous sarcomas: Dermatofibrosarcoma protuberans and cutaneous leiomyosarcoma

“…This is the mechanism being targeted with small molecule tyrosine kinase inhibitor therapy such as imatinib. 25,34,37 Furthermore, detection of this chromosomal aberration by FISH (Fluorescence In Situ Hybridization) represents an invaluable diagnostic tool, particularly in cases of DFSP-FS and other unusual variants, since all of which will exhibit the cytogenetic signature 18,19,21,25,38,39 . Interestingly, this same signature cytogenetic aberration is present in the childhood tumor Giant Cell Fibroblastoma (GCF), with known reported cases showing hybrid DFSP/GCF features.…”