Elastofibroma is a rare, benign, slow-growing degenerative pseudotumor that typically occurs in the subscapular region and has been considered a peculiar fibroblastic proliferation with accumulation of abnormal elastic fibers. Very little is known about the cytogenetic and molecular genetic changes in elastofibroma. In the present study, we analyzed DNA copy number changes in 27 elastofibromas by comparative genomic hybridization. DNA was extracted from 22 archival paraffin-embedded tumor tissues and from 5 fresh frozen samples. Nine (33%) of the 27 cases exhibited DNA copy number changes involving one or two chromosomes, whereas the remaining 18 cases exhibited no DNA copy number changes. The majority of the changes were gains (8 cases), whereas 2 cases showed losses. The most common recurrent gains were at chromosomal locations Xq12-q22 (6 cases) and 19 (2 cases). High-level amplifications and recurrent losses were not observed. There was no correlation between DNA copy number changes and the pseudotumor size. The present study has identified a chromosomal region that may contain genes involved in the development of at least some elastofibromas.