Association of allelic loss at 8p22 with poor prognosis among breast cancer cases treated with high-dose adjuvant chemotherapy

To identify specific allelic losses that might correlate with postoperative mortality of breast cancer patients treated with high-dose adjuvant chemotherapy consisting of cyclophosphamide, methotrexate and fluorouracil, we examined tumors from a cohort of 150 such patients, who were followed clinically for 5 years postoperatively, for allelic losses (loss of heterozygosity, LOH) among 18 microsatellite markers throughout the genome. Patients whose tumors had lost an allele at 8p22 had significantly higher risks of mortality than those whose tumors retained both alleles at those loci. At 8p22, the 5-year mortality rate was 31% among patients with losses vs. 8% with retention (P=0.0354). No other region showed correlation between LOH and prognosis. The data indicate that LOH at 8p22 is a significant predictor of postoperative mortality for breast cancer patients who received high-dose postoperative adjuvant chemotherapy. Thus, LOH at 8p22 can serve as a negative prognostic indicator to guide postoperative management of patients.