Liposclerosing Myxofibrous Tumor: A Separated Clinical Entity?

Area of Science:

• Orthopedic Oncology
• Skeletal Radiology
• Molecular Pathology

Background:

• Liposclerosing myxofibrous tumors (LSMFTs) are infrequent, peculiar fibrous dysplasia variants.
• LSMFTs predominantly affect the intertrochanteric femoral region.
• These tumors are often not recognized as a distinct entity and can be misdiagnosed.

Purpose of the Study:

• To analyze the clinical, radiological, histopathological, and molecular features of LSMFTs.
• To differentiate LSMFTs from other bone lesions.
• To improve diagnostic accuracy and prevent overtreatment.

Main Methods:

• Retrospective analysis of 15 new LSMFT cases.
• Comparison with 241 previously reported LSMFT cases from English literature.
• Review of clinical, radiological, histopathological, and molecular data.

Main Results:

• Radiographically, LSMFTs appear as well-defined intraosseous lytic masses with sclerotic rims and internal calcifications.
• Histopathology reveals variable spindle cells, bone matrix, adipose tissue, and cystic spaces in a fibromyxoid stroma.
• Molecular testing identified GNAS and TP53 mutations.

Conclusions:

• Familiarity with LSMFT's typical radiological appearance is essential.
• Heterogeneous histopathological findings, especially in small biopsies, necessitate careful evaluation.
• Accurate diagnosis prevents misdiagnosis and unnecessary aggressive treatment.