@article{4b1ee20b8289446cac1553b710f3c643,
title = "Molecular Characterization of a Rare Dedifferentiated Liposarcoma With Rhabdomyosarcomatous Differentiation in a 24 Year Old",
abstract = "Aims. The aim of this study was to identify potential driver genetic alterations in a dedifferentiated liposarcoma (DDLPS) with rhabdomyosarcomatous differentiation. Methods and Results. A 24-year-old female underwent resection of an abdominal mass, which on a previous biopsy demonstrated rhabdomyosarcomatous differentiation concerning for embryonal rhabdomyosarcoma. Histologically the resected tumor displayed a high-grade sarcoma with rhabdomyosarcomatous differentiation in the background of well-differentiated liposarcoma consistent with DDLPS. Fluorescence in situ hybridization confirmed MDM2 amplification, as did array-based copy number profiling. Whole-exome sequencing revealed a somatic FGFR1 hotspot mutation and RNA sequencing an LMNB2-MAP2K6 fusion only within the dedifferentiated component. Conclusions. This study represents an in-depth examination of a rare DDLPS with rhabdomyosarcomatous differentiation in a young individual. Additionally, it is also instructive of a potential pitfall when assessing for MDM2 amplification in small biopsies. Despite exhaustive analysis, mutation and gene copy number analysis did not identify any molecular events that would underlie the rhabdomyoblastic differentiation. Our understanding of what causes some tumors to dedifferentiate as well as undergo divergent differentiation is limited, and larger studies are needed.",
keywords = "liposarcoma, dedifferentiation, rhabdomyosarcoma, MDM2, amplification, DIVERGENT MYOSARCOMATOUS DIFFERENTIATION, READ ALIGNMENT, MUTATIONS, ONCOGENE, AMPLIFICATION, DISCOVERY, PROMOTER",
author = "Nicholas Olson and Rodrigo Gularte-Merida and Pier Selenica and Paula, {Arnaud Da Cruz} and Barbara Alemar and Britta Weigelt and Joel Lefferts and Konstantinos Linos",
note = "Funding Information: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: B. Weigelt is funded in part by Cycle for Survival. Research reported in this publication was supported in part by a Cancer Center Support Grant of the National Institutes of Health/National Cancer Institute (Grant No. P30CA008748). Funding Information: https://orcid.org/0000-0002-6745-3587 Olson Nicholas MD 1 Gularte-M{\'e}rida Rodrigo PhD 2 Selenica Pier BSc 2 3 Da Cruz Paula Arnaud PhD 2 Alemar Barbara PhD 2 Weigelt Britta PhD 2 Lefferts Joel PhD 1 Linos Konstantinos MD 1 1 Dartmouth-Hitchcock Medical Center and Geisel School of Medicine, Lebanon, NH, USA 2 Memorial Sloan Kettering Cancer Center, New York, NY, USA 3 University of Maastricht, Maastricht, Netherlands Konstantinos Linos, Department of Pathology & Laboratory Medicine, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, Lebanon, NH 03756, USA. Email: Konstantinos.Linos@hitchcock.org 11 2019 1066896919890401 {\textcopyright} The Author(s) 2019 2019 SAGE Publications Aims . The aim of this study was to identify potential driver genetic alterations in a dedifferentiated liposarcoma (DDLPS) with rhabdomyosarcomatous differentiation. Methods and Results . A 24-year-old female underwent resection of an abdominal mass, which on a previous biopsy demonstrated rhabdomyosarcomatous differentiation concerning for embryonal rhabdomyosarcoma. Histologically the resected tumor displayed a high-grade sarcoma with rhabdomyosarcomatous differentiation in the background of well-differentiated liposarcoma consistent with DDLPS. Fluorescence in situ hybridization confirmed MDM2 amplification, as did array-based copy number profiling. Whole-exome sequencing revealed a somatic FGFR1 hotspot mutation and RNA sequencing an LMNB2-MAP2K6 fusion only within the dedifferentiated component. Conclusions . This study represents an in-depth examination of a rare DDLPS with rhabdomyosarcomatous differentiation in a young individual. Additionally, it is also instructive of a potential pitfall when assessing for MDM2 amplification in small biopsies. Despite exhaustive analysis, mutation and gene copy number analysis did not identify any molecular events that would underlie the rhabdomyoblastic differentiation. Our understanding of what causes some tumors to dedifferentiate as well as undergo divergent differentiation is limited, and larger studies are needed. liposarcoma dedifferentiation rhabdomyosarcoma MDM2 amplification Cancer Center Support Grant of the National Institutes of Health/National Cancer Institute Grant No. P30CA008748 edited-state corrected-proof Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: B. Weigelt is funded in part by Cycle for Survival. Research reported in this publication was supported in part by a Cancer Center Support Grant of the National Institutes of Health/National Cancer Institute (Grant No. P30CA008748). Ethical Approval Not applicable, because this article does not contain any studies with human or animal subjects. Informed Consent Not applicable, because this article does not contain any studies with human or animal subjects. Trial Registration Not applicable, because this article does not contain any clinical trials. ORCID iD Nicholas Olson https://orcid.org/0000-0002-6745-3587 Supplemental Material Supplemental material for this article is available online. Publisher Copyright: {\textcopyright} The Author(s) 2019.",
year = "2020",
month = jun,
doi = "10.1177/1066896919890401",
language = "English",
volume = "28",
pages = "454--463",
journal = "International Journal of Surgical Pathology",
issn = "1066-8969",
publisher = "SAGE Publications Inc.",
number = "4",
}