Correlation of allelic loss with poor postoperative survival in breast cancer

Background: Allelic losses of tumor suppressor genes or the chromosomal regions harboring them in the DNA of tumor cells may become useful postoperative prognostic indicators. Methods: To examine whether specific allelic losses correlate with postoperative survival in a fiveyear prospective follow-up, we tested tumors from a cohort of 504 breast cancer patients for allelic loss of 1 8 microsatellite markers representing either known tumor suppressor genes or regions where genetic alterations are frequent in breast tumors. Results: Patients with allelic loss at 1 p34, 3p25, 8p22, 13q12, 17pl 3.3, or 17q21.1 had a significantly higher risks of postoperative mortality compared with those whose tumors retained both alleles at those loci (at lp34, the 5-year mortality rate was 23% among patients with loss vs 10% with retention, ρ = 0.0100; at 3p25, 22% vs 9%, ρ = 0.0014; at 8p22, 24% vs 7%, ρ = 0.0177; at 13q12, 19% vs 8%, ρ = 0.0093; at 17pl3.3, 19% vs 9%, ρ = 0.0078; and at 1 Zq 21.1, 17% vs 10%, ρ = 0.0475). Conclusion: Allelic losses at these loci can serve as negative prognostic indicators to guide postoperative management, especially in the selection of those who will benefit from intensive adjuvant therapies.