Epidermal growth factor receptor (EGFR) mutation incidence in Caucasian ovarian cancer patients

Abstract

Aims: The EGFR is over expressed in 55% to 98% of advanced epithelial ovarian carcinoma. Different studies demonstrated EGFR status as an independent prognostic factor for ovarian cancer. Recent studies in non small cell lung cancer suggest that the presence of the clinical response to tyrosine kinase inhibitors (e.g. ZD 1839) correlates with the somatic mutations in the kinase domain of EGFR, exons 18–21. For patients with ovarian cancer data are not available on EGFR gene mutation. Material and Methods: Shock-frozen samples from 32 patients with primary of ovarian cancer were stratified in two groups according to disease-free interval: ≤6 months (17 patients.) and <6 months (15 patients). All patients were prospectively collected within Tumor bank Ovarian Cancer Project (TOC). Patient collective consisted only from west European Caucasian women. Additionally, 9 commercial available ovarian cancer cell lines (TOV-90, TOV-112D, TOV-21G, OVCAR-3, A2780, A2780 ADR, ES-2, SK-OV-3, and Caov-3) and 32 established ovarian cancer lines were analysed. Exon sequencing of genomic DNA was used to detect L858R deletion mutations of EGFR within exons 21 of the kinase domain. PCR and capillary electrophoresis (Chip-Format) were used to analyse 15 bp deletion in Exon 19. We focused on descriptive analysis. The Log-Rank test was applied to confirm statistically significance (p-value of <0.05). Results: 74.6% of the pts. were diagnosed FIGO stage III-IV. Median follow-up period was: 14.17 month (range: 2–42 months). Whether in cell lines, nor in tumor samples, stratified to response of platinum therapy any mutation of EGFR gene was observed. Conclusions: Our study indicates that the prevalence of mutation in the kinase domain of EGFR, exons 19 and 21 seems to be very low in patients with advanced ovarian cancer. Further studies should investigate other ethical groups of patients.