Pathogenic NF1 truncating mutation and copy number alterations in a dedifferentiated liposarcoma with multiple lung metastasis: A case report

Background: Dedifferentiated liposarcoma (DDLPS), which accounts for an estimated 15-20% of liposarcomas, is a high-grade and aggressive malignant neoplasm, exhibiting a poor response to available therapeutic agents. However, genetic alteration profiles of DDLPS as well as the role of NF1 mutations have not been studied extensively. Case presentation: The current study reports a patient presenting with rapidly growing DDLPS accompanied by multiple lung and pleural metastases, in whom whole-exome sequencing revealed a NF1 truncating mutation of the known pathogenic variant, c.C7486T, p.R2496X, as well as multiple copy number alterations (CNAs), including the well-known 12q13-15 amplification, and multiple chromothripsis events encompassing potential cancer-related genes. Conclusions: Our results suggest that, in addition to the 12q13-15 amplification, NF1 inactivation mutation and other CNAs may contribute to DDLPS tumorigenesis accompanied by aggressive clinical features.