New PLAG1-fusion transcripts in the spectrum of pediatric fibrotic, lipofibrotic, and mature lipomatous tumors

Bernhard Theis; Ilmi Alhussami; Elke Kämmerer; Karim Kentouche; Christian Vokuhl; Nikolaus Gassler; Kathrin Katenkamp

New PLAG1-fusion transcripts in the spectrum of pediatric fibrotic, lipofibrotic, and mature lipomatous tumors

Int J Clin Exp Pathol. 2022 Oct 15;15(10):425-430. eCollection 2022.

Authors

Bernhard Theis¹, Ilmi Alhussami², Elke Kämmerer³, Karim Kentouche³, Christian Vokuhl⁴, Nikolaus Gassler¹, Kathrin Katenkamp¹

Affiliations

¹ Section Pathology, Institute of Forensic Medicine, Jena University Hospital Jena 07747, Germany.
² Department of Pediatric Surgery, Jena University Hospital Jena 07747, Germany.
³ Section of Pediatric Hematology and Oncology, Department of Pediatrics, Jena University Hospital Jena 07747, Germany.
⁴ Institute of Pathology, Section Paidopathology, University Hospital Bonn Bonn 53127, Germany.

PMID: 36381419
PMCID: PMC9638836

Abstract

The histomorphology of liboblastoma is highly variable and comprises different patterns that are found admixed or in pure form within a tumor. The most important features - mature lipomatous, fibrotic, lipofibrous, and myxoid - overlap with the histomorphology of several other pediatric tumor entities. Regarding the morphologic overlaps, molecular diagnostics with identification of fusion transcripts involving PLAG1 or HMGA2 is essential to identify lipoblastomas. This paper describes the diagnostic procedure in general and two new fusion transcripts of lipoblastoma, MEG3-PLAG1 and COL1A1-PLAG1. In conclusion, the algorithm to diagnose lipoblastomas among this group of pediatric fibrotic, lipofibrous and mature lipomatous tumors essentially includes histomorphology, immunohistochemistry, and molecular diagnostics.

Keywords: Lipoblastoma; PLAG1-fusion; molecularpathology; pediatric tumor.

Publication types

Case Reports