Malignant peripheral nerve sheath tumor in children: A clinicopathologic and molecular study with parallels to the adult counterpart Journal Article


Authors: Agaram, N. P.; Wexler, L. H.; Chi, P.; Antonescu, C. R.
Article Title: Malignant peripheral nerve sheath tumor in children: A clinicopathologic and molecular study with parallels to the adult counterpart
Abstract: Malignant peripheral nerve sheath tumors (MPNST) are aggressive neoplasms, arising either sporadically, in the setting of neurofibromatosis type I (NF1) or post radiation. Most MPNST occur in adults and their pathogenesis is driven by the loss of function mutations in the PRC2 complex, regardless of their clinical presentation. In contrast, pediatric MPNST are rare and their pathogenesis has not been elucidated. In this study, we investigate a large cohort of 64 MPNSTs arising in children and young adults (younger than the age of 20 years) to better define their clinicopathologic and molecular features. Sixteen (25%) cases were investigated by MSK-IMPACT, a targeted NGS panel of 505 cancer genes. Most patients (80%) were aged 11-20 years. A history of NF1 was established in half of the cases. Mean tumor size was 8.5 cm. The most common locations included the extremities (34%) and abdomen/pelvis (27%). Histologically, 89% of high-grade MPNST showed conventional features, while the remaining three cases showed a predominant epithelioid phenotype. Heterologous differentiation occurred in 25% of high grade cases, with half showing rhabdomyoblastic differentiation. Tumors arose in a background of a plexiform neurofibroma (16%), neurofibroma (13%), and schwannoma in two cases (3%). Immunohistochemically, H3K27me3 expression was lost in 82% of conventional high-grade MPNST analyzed, while loss of SMARCB1 expression was seen in one epithelioid MPNST. Genomically, all cases showed more than one genetic abnormality, with 53% showing mutations in EED / SUZ12 genes, and 47% of cases harboring alterations in NF1 and CDKN2A/CDKN2B genes. At the last follow-up, 30% patients died of disease, 28% were alive with disease and 42% had no evidence of disease. NF1 status did not correlate with overall survival. In conclusion, half of pediatric and young adult MPNST were NF1-related and showed loss of function alterations in PRC2 complex, NF1, and CDKN2A, similar to the adult counterpart. Thus, H3K27me3 loss of expression may be used in the diagnosis of high grade MPNSTs in children. Moreover, a small subset of pediatric MPNST have an epithelioid morphology with different pathogenesis.
Keywords: neurofibromatosis; children; mpnst; neurofibroma; suz12; prc2
Journal Title: Genes Chromosomes and Cancer
Volume: 62
Issue: 3
ISSN: 1045-2257
Publisher: Wiley Periodicals, Inc  
Date Published: 2023-03-01
Start Page: 131
End Page: 138
Language: English
ACCESSION: WOS:000892466800001
DOI: 10.1002/gcc.23106
PROVIDER: wos
PMCID: PMC9825640
PUBMED: 36414547
Notes: The MSK Cancer Center Support Grant (P30 CA008748) is acknowledged in the PDF --Corresponding author is MSK author: Narasimhan P. Agaram -- Source: Wos
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MSK Authors
  1. Leonard H Wexler
    192 Wexler
  2. Narasimhan P Agaram
    190 Agaram
  3. Cristina R Antonescu
    897 Antonescu
  4. Ping Chi
    173 Chi