Atypical spindle cell lipomatous tumor/atypical pleomorphic lipomatous tumor and atypical mammary-type myofibroblastoma: clinicopathological, immunohistochemical, and multiplex fluorescence in situ hybridization analyses

• Published in: Chinese medical journal Vol. 134; no. 19; pp. 2370 - 2372
• Main Authors: Zhang, Zhang, Liu, Nan, Chen, Min, Peng, Ran, Chen, Hui-Jiao, Zhang, Hong-Ying
• Format: Journal Article
• Language: English
• Published: China Lippincott Williams & Wilkins Ovid Technologies 05.10.2021; Lippincott Williams & Wilkins; Wolters Kluwer
• Subjects: Adipocytes; Biomarkers, Tumor; Correspondence; Diagnosis, Differential; Gene amplification; Humans; Hybridization; In Situ Hybridization, Fluorescence; Lipoma - diagnosis; Lipoma - genetics; Liposarcoma; Morphology; Neoplasms, Muscle Tissue - genetics; Neoplasms, Muscle Tissue - surgery; Sarcoma; Tumors; United States > US; China
• ISSN: 0366-6999; 2542-5641
• DOI: 10.1097/CM9.0000000000001692

In atypical MTMF, the hyperchromatic spindle cells coexpressed desmin, CD34, and estrogen receptor, suggesting the differentiation of myofibroblastic tumors. [...]atypical MTMF was negative for cytokeratine, the MDM2 gene, and the CDK4 gene, with no nuclear Rb expression [Figure 1D]. [...]our study is the first cytogenetic analysis to verify the codeletion status of the RB1 and FOXO1 genes in APLT (cases 17 and 21) and atypical MTMF (case 15), demonstrating that APLTs and atypical MTMF share obvious overlapping clinical, morphologic, immunohistochemical, and cytogenetic characteristics with ASLTs. [...]case 16 and case 20 had 2F1O signals by FISH, demonstrating only RB1 deletions but not FOXO1 deletions, which suggest that RB1 deletions are more frequent than FOXO1 deletions. According to the control cases and differential diagnosis, ALT/WDLS showed MDM2 amplifications and FUS rearrangement was observed in low-grade fibromyxoid sarcomas.