Spindle Cell Lipoma : Cytogenetics

Comments:
Cytogenetics: Deletions of chromosome arm 13q or loss of the entire chromosome 13 are found in the majority of spindle cell/pleomorphic lipomas. Breakpoints occur in 13q14 region resulting in the loss of tumor suppressor gene RB1, encoding the Rb protein. The same deletion is also found in cellular angiofibromas and mammary and soft tissue myofibroblastomas. In addition, rearrangements involving chromosomes 16, 1, 12, and 11 have also been detected. Spindle cell and pleomorphic lipomas don't have giant marker and ring chromosomes that are seen in atypical lipomatous tumor/well-differentiated liposarcoma.

About this image: G-banding and FISH analysis on two cellular angiofibromas. The top panel shows rearrangements involving chromosomes 13 and 16 and loss of RB1 in one case. The bottom panel shows rearrangements involving chromosome 13 and RB1 deletion in a second case. Image source: Panagopoulos I. et al. Loss of chromosome 13 material in cellular angiofibromas indicates pathogenetic similarity with spindle cell lipomas. Diagnostic Pathology (2017) Feb 13;12(1):17. doi: 10.1186/s13000-017-0607-6. Used under Creative Commons Attribution 4.0 International License.