GENETIC ABERRATIONS IN ADRENOCORTICAL TUMORS-DETECTED USING COMPARATIVE GENOMIC HYBRIDIZATION CORRELATE WITH TUMOR SIZE AND MALIGNANCY

The differentiation between malignant and benign adrenocortical tumors is often difficult, and better markers are required. Because the gene tic background of adrenocortical tumors is poorly characterized, we us ed comparative genomic hybridization (CGH) to screen for DNA sequence copy number changes in 8 sporadic primary adrenocortical cancers and 1 4 adenomas. There was a strong relationship between the number of gene tic aberrations detected using CGH and both tumor size and malignancy. No alterations were seen in the smaller adenomas (<5 cm), whereas the two largest adenomas (5 cm each) and seven of the eight cancers (7-20 cm) showed an increased number of genetic alterations, The presence o f genetic aberrations detected using CGH was associated with an aneupl oid DNA pattern. In the cancers, losses most often involved the chromo somal regions 2, 11q, and 17p (four of eight tumors), whereas gains to ok place at chromosomes 4 and 5 (four of eight tumors). In conclusion, our data indicate that genetic changes may help to define the maligna nt potential of adrenocortical tumors. Furthermore, the CGH results im plicate several chromosomal regions that may contain genes with an imp ortant role in the development of adrenocortical cancers.