title: Intramuscular dendritic fibromyxolipoma: myxoid variant of spindle cell lipoma?
abstract: Dendritic fibromyxolipoma (DFML) is an uncommon, recently described, benign soft tissue lesion that shares many clinical and pathological features with myxoid variants of spindle cell lipoma (SCL). As described, DFML is distinguished from SCL by the presence of dendritic cytoplasmic processes, abundant keloidal collagen and a prominent, often plexiform vascular pattern. We describe the first known reported case of an intramuscular DFML that occurred in the right shoulder region of a 73-year-old man. The tumor displayed the typical histopathological features of DFML but also included foci of chondroid metaplasia, a previously unreported finding. This report also discusses the differential diagnosis, particularly distinguishing DFML from SCL and myxoid liposarcoma. In view of the similarities in many clinical and pathological features between SCL and DFML, we speculate that DFML probably represents an unusual variant of myxoid SCL.
authors.affiliation: Department of Anatomical Pathology, Royal Prince Alfred Hospital, Sydney, Australia.
authors.forename: Rooshdiya Z
authors.initials: RZ
authors.lastname: Karim
authors.forename: Stanley W
authors.initials: SW
authors.lastname: McCarthy
authors.forename: Allan A
authors.initials: AA
authors.lastname: Palmer
authors.forename: S Fiona
authors.initials: SF
authors.lastname: Bonar
authors.forename: Richard A
authors.initials: RA
authors.lastname: Scolyer
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor; D003713:Dendritic Cells / Q000737:chemistry / Q000473:pathology*; D003937:Diagnosis, Differential; D018572:Disease-Free Survival; D005350:Fibroma / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007124:Immunoenzyme Techniques; D008067:Lipoma / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D018208:Liposarcoma, Myxoid / Q000737:chemistry / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D019042:Muscle Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor