Single nucleotide polymorphisms analysis of BRAC and ERCC1 as predictor of recurrence after chemoradiation for cervical cancer patients.
e13540 Background: A number of patients with locally advanced cervical cancer will recur despite presenting initial response to chemoradiation. Single-nucleotide polymorphisms (SNP) of DNA repair genes have been found to be predictors of efficacy of chemotherapy and radiotherapy. Methods: We evaluated the presence of SNP in ERCC1, BRAC 1 and 2 genes. We analysed paraffin-embedded biopsies from patients who had relapsed after receiving treatment with chemoradiation, for SNP of the mentioned genes. The status of the alleles wild type (wt) or at least 1 SNP was compared with time to progression (TTP) and toxicity. Results: 90 patients who experience recurrence of their cervical cancer were included in the analysis. Of those, we only could obtain evaluable tumour from 43 patients. Median age: 52.5 yrs (31-81). Histology: 32 squamous cell, 8 adenocarcinoma, 3 adenosquamous. One SNP in BRAC1 (rs12516) was found to be significantly associated with better TTP for the mutant variant compared to the wild-type (124 m. vs. 14 m.). Furthermore, all six patients who presented with severe (grade 3-4) toxicity had this wild-type SNP (rs12516) in BRAC1 gene. Conclusions: We have identified a SNP which confers better outcome in patients with cervical cancer. Further analysis need to be done to determine its relation to radiation-induced toxicity in this group of patients.