Adipose tissue tumors are often characterized by typical or even speci
fic chromosomal alterations. In some of the cases the molecular backgr
ound of these microscopically visible alterations was already elucidat
ed. In myxoid liposarcomas the translocation t(12;16) creates a fusion
gene between the CHOP gene and the FUS gene and in lipomas the HMGI-C
gene becomes rearrranged by structural aberrations involving chromoso
mal region 12q14-15. Based on examples of a lipoma, a well-differentia
ted liposarcoma, a myxoid liposarcoma, and an aggressive angiomyxoma i
t is demonstrated in the present paper how cytogenetic investigation c
an be used as an additional tool for an improved diagnosis of adipose
tissue tumors. Furthermore, the detection of molecular mechanisms unde
rlying the visible cytogenetic alterations will certainly significantl
y increase our knowledge about the pathogenesis of these diseases.