Abstract

Background: Excision repair cross-complementation group 1 (ERCC1) expression and some polymorphisms of the gene could predict treatment efficacy in patients with different types of tumors receiving platinum-based treatments. The purpose of this study is to correlate ERCC1 gene polymorphism and protein expression by immunohistochemistry (ICH) with recurrence free survival (RFS) and overall survival (OS) in locally advanced cervical squamous cell carcinoma patients who have undergone cisplatin-based concurrent chemoradiotherapy (CRT). Methods: Sixty-six patients with locally advanced cervical squamous cell carcinoma treated with radical CRT from a cooperative group were evaluated. This group studied the polymorphism that causes a single nucleotide change C to T at codon 118 -becoming AAC on AAT- resulting in a decreased ERCC1 gene expression carrying a loss of DNA repair activity, using quantitative real-time PCR in blood samples. ERCC1 protein expression was determined in pre-treatment tumor tissues by IHC. The association of ERCC1 status with clinicopathological characteristics (age, hemoglobin, grade, FIGO stage) and treatment outcome were analyzed. Results: Thirty-three patients (50%) were homozygous for AAC codon (C/C genotype), 17 (26%) were homozygous for AAT codon (T/T genotype), and 16 (24%) were heterozygous (C/T genotype). Thirty-eight percent of patients were ERCC1 negative or low expression by IHC, whereas 62% were positive. There was a significant association of C/C genotype and positive ERCC1 by IHC (p 0.003). No significant correlation between ERCC1 expression, codon 118 polymorphism and clinicopathological characteristics was observed. No difference was observed between C/C or non C/C genotypes in terms of RFS or OS. Positive ERCC1 expression by IHC was related to worse RFS (p 0.04). Conclusions: C/C genotype was associated to high expression of the protein but without impact on RFS or OS. ERCC1 expression by IHC has been shown to be a biomarker for RFS in cervical squamous cell carcinoma patients treated with CRT.page2image18864

17th ECCO - 38th ESMO -32 ESTRO European Cancer Congress, 27 Sept -1 Oct, 2013, Amsterdam, Holland. Abstract # 3095, Poster#

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