Eleven wood-workers with sinonasal adenocarcinoma were analyzed by comparative genomic hybridization. This technique serves as a screening test for regions of copy number changes in tumor genomes. We have applied the technique to map DNA gains and losses in 9 cases of formalin-fixed, paraffin-embedded tumors and 2 cases of frozen tumors. Gains were found most frequently than losses. Whole arm chromosomic gains were detected in high frequencies at 8q, 7q, 12q and 18p and losses at 18q, 8p, 10q, 5q, 14q and 17p. The segment most frequently amplified was 18p11.1-q11 (45%), even though others like 7q21-22 (18%) were related with lower survival rates. This analysis allows us to know for the first time the chromosomic aberrations that occur and may play an important role in sinonasal adenocarcinoma. In the future, comparative genomic hybridization could be used in the woodworkers with long exposition to wood dust to detect initial genetic aberrations and obtain an early treatment and diagnosis of the disease.