Polymorphisms May Affect Course of Metastatic Breast Cancer
Variants in XRCC1, XRCC3 and CCND1 associated with poorer survival
WEDNESDAY, Dec. 27 (HealthDay News) -- Single nucleotide polymorphisms (SNPs) in the DNA repair genes XRCC1-01 and XRCC3-01, and the cell cycle control gene CCND1-02, may predict survival in patients with metastatic breast cancer who undergo DNA damaging chemotherapy, according to a report published in the Dec. 20 issue of the Journal of Clinical Oncology.
Mary A. Bewick, research technician at Sudbury Regional Hospital, Regional Cancer Center in Sudbury, Ontario, Canada, and colleagues evaluated SNPs in 95 patients with metastatic breast cancer who were enrolled in five prospective clinical trials of high-dose chemotherapy and autologous stem-cell transplantation.
The researchers found that the hazard ratios for breast cancer specific survival were 2.8 for XRCC1-01, 2.0 for XRCC3-01 and 1.8 for CCND1-02. They found that the hazard ratios for progression-free survival were 2.0 for both XRCC1-01 and XRCC3-01, and 1.8 for CCND1-02. Compared to patients with no gene variants, patients carrying either one variant genotype or combinations of any two variant genotypes had significantly poorer hazard ratios for breast cancer specific survival (1.7 and 4.7, respectively).
"To our knowledge, this is the first study to show that polymorphisms in XRCC1 and XRCC3 are associated with survival outcome of patients with metastatic breast cancer," the authors write. The development of additional studies may "further help define their role and value in the clinical setting."