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Comparative genomic hybridization was used to screen colorectal carcinomas for chromosomal aberrations that are associated with the metastatic phenotype of the lung. Thirteen lung metastases, six primary tumors, one lymph node metastasis, one liver metastasis, and one ovarian metastasis were investigated and added to our CGH colon cancer tumor collective, comprising 85 tumor specimens from 56 patients (see CGH online tumor database at http://amba.charite.de/cgh). Lung metastases showed more alterations than liver metastases, particularly more deletions at 1p, 3p, 9q, 12q, 17q, 19p and 22q and gains at 2q, 5p, and chromosome 6. Comparing lung metastases with their corresponding primary tumors, particularly more deletions at 3p, 8p, 12q, 17q, and 21q21 and gains at 5p were observed. Based on our results, we wish to suggest a metastatic progression model. Specific subpopulations of metastatic cells have a distinct metastatic potential which is reflected by a non-random accumulation of chromosomal alterations. Distinct alterations already exist within the primary tumor and this “ready to go package” gives the cells the metastatic potential to achieve the complex series of events needed for metastasis.

98th AACR Annual Meeting-- Apr 14-18, 2007; Los Angeles, CA