title: Presence of C11orf95-MKL2 fusion is a consistent finding in chondroid lipomas: a study of eight cases.
abstract: OBJECTIVE
  Chondroid lipomas are benign adipose tissue tumours. Their rarity and peculiar morphology can lead to misinterpretation, especially in small biopsies. Based on a recurrent translocation t(11;16)(q13;p13), the C11orf95-MKL2 fusion gene has been found in a few cases. Therefore, it seemed appropriate to look for this fusion gene in a larger cohort.
  
  
  RESULTS
  We describe eight further cases from four females and four males with an age range of 21-81 years (median 49 years). The tumours were situated in the lower arm (three), lower leg (two), thigh (one), back (one) and head (one); seven lesions were deep-seated and one was located subcutaneously. Sizes ranged from 3 to 12 cm (median 6.3 cm). All patients were treated by simple excision, and follow-up, available for six patients (range 2 months-12 years; median 15 months), demonstrated recurrence in one case. Histologically, the circumscribed and lobulated tumours showed a variable composition of adipocytes, lipoblasts, hibernoma-like cells and chondroblast-like cells embedded in a chondroid matrix. Immunohistochemistry, performed in four cases, revealed positivity for S-100 and pancytokeratin in two of three neoplasms stained for each marker. A C11orf95-MKL2 fusion gene was shown by RT-PCR analysis in seven of the eight cases.
  
  
  CONCLUSIONS
  Molecular analysis can be used to support the diagnosis of chondroid lipoma, especially in small samples. This may be helpful in planning treatment when the differential diagnosis includes malignant lesions.
authors.affiliation: Department of Pathology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. u.flucke@pathol.umcn.nl
authors.forename: Uta
authors.initials: U
authors.lastname: Flucke
authors.forename: Bastiaan B J
authors.initials: BB
authors.lastname: Tops
authors.forename: Nicolas
authors.initials: N
authors.lastname: de Saint Aubain Somerhausen
authors.forename: Johannes
authors.initials: J
authors.lastname: Bras
authors.forename: David H
authors.initials: DH
authors.lastname: Creytens
authors.forename: Benno
authors.initials: B
authors.lastname: Küsters
authors.forename: Patricia J T A
authors.initials: PJ
authors.lastname: Groenen
authors.forename: Marian A J
authors.initials: MA
authors.lastname: Verdijk
authors.forename: Albert J H
authors.initials: AJ
authors.lastname: Suurmeijer
authors.forename: Thomas
authors.initials: T
authors.lastname: Mentzel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics*; D002885:Chromosomes, Human, Pair 16 / Q000235:genetics; D005260:Female; D050939:Gene Fusion; D006801:Humans; D008067:Lipoma / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018205:Neoplasms, Adipose Tissue / Q000235:genetics* / Q000473:pathology; D016366:Open Reading Frames; D011506:Proteins / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014178:Translocation, Genetic; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D011506:Proteins; D014157:Transcription Factors; C585140:ZFTA protein, human; C478036:MRTFB protein, human