Journal Article

Soft tissue tumor with novel NR1D1-MAML1 fusion in a pediatric case

Yamamoto Nobuyuki, Komatsu Masato, Hara Hitomi, Akisue Toshihiro, Kanzawa Maki, Iijima Kazumoto, Nishimura Noriyuki, Jimbo Naoe, Kajimoto Kazuyoshi, Uemura Suguru, Kawamoto Teruya, Kawakami Yohei, Kuroda Ryosuke, Itoh Tomoo, Hirose Takanori

2020

Overview

We herein describe soft tissue tumor arising in the lower extremity of a pediatric patient. The tumor displayed a unique and wide range of histological features, sheet-like and cohesive growth pattern consisting of enlarged round to epithelioid atypical cells with a large alveolar and pseudopapillary histological architecture, focally mimicking alveolar soft part sarcoma and MiT family translocation renal cell carcinoma. Tumor cells were focally immunoreactive for cytokeratin, S-100, and EMA. RNA sequencing identified a novel in-frame NR1D1 (exon 5)-MAML1 (exon 2) gene rearrangement resulting in the formation of a putative chimeric protein containing the N-terminal C4-type zing finger domains of NR1D1 and the C-terminal MAML1 protein, which was confirmed by subsequent RT-PCR, Sanger sequencing, and FISH assay. To the best of our knowledge, NR1D1-MAML1 fusion has not yet been described in any neoplasms, suggesting the emergence of a novel tumor entity.

• Publisher: Springer Nature B.V
• Subject: Alveoli / Cytokeratin / Gene rearrangement / Gene sequencing / Growth patterns / Kidney cancer / Mimicry / Neoplasia / Neoplasms / Pediatrics / Polymerase chain reaction / Proteins / Renal cell carcinoma / Ribonucleic acid / RNA / Sarcoma / Soft tissues / Translocation / Tumor cells / Tumors