[Primary Orbital Liposarcoma].

A 30-year-old male patient presented with a painful globe subluxation of the left eye since two weeks. Painless left proptosis had been noted at least 2 years earlier. An MRI performed one year after onset of symptoms showed a retrobulbar mass, which on biopsy was diagnosed as spindle cell lipoma. Surgical debulking via a transconjunctival approach successfully reduced proptosis; repeated histology with extensive immunohistochemical analysis now led to the diagnosis of a well-differentiated orbital liposarcoma. The patient underwent orbital exenteration and received adjuvant radiotherapy. Genetic testing showed a heterozygote mutation of the ATM-gene on chromosome 11.