Desislava Dimitrova

BRCA1 gene promoter methylation status in high-grade serous ovarian cancer patients - A study of the tumour Bank ovarian cancer (TOC) and ovarian cancer diagnosis consortium (OVCAD)

BACKGROUND Mutations in BRCA1/2 genes are involved in the pathogenesis of breast and ovarian cancer. Inactivation of these genes can also be mediated by hypermethylation of CpGs in the promoter regions. Aim of this study was to analyse the clinical impact of BRCA1 promoter gene methylation status in a homogenous cohort of high-grade serous ovarian cancer (HGSOC) patients. METHODS The cohort included 257 primary HGSOC patients treated by cytoreduction and platinum-based chemotherapy. DNA was extracted from fresh frozen tissue samples. BRCA1 gene promoter methylation rate was assessed using polymerase chain reaction (PCR). RESULTS 14.8% of patients presented hypermethylation within a selected region of the BRCA1 promoter. The rate of hypermethylation was significantly higher in younger patients (20.8% hypermethylation in the age group ⩽ 58 years versus 8.7% hypermethylation in the age group >58 years; p = 0.008). Optimal tumour debulking could be reached in 63% of patients, without significant differences in the extent of residual disease with respect to the methylation status. No impact of BRCA1 gene promoter methylation status on progression free- and overall-survival rates was found. No significant differences within BRCA1 promoter methylation status between primary and metastatic tissue could be observed. These results on BRCA1 promoter methylation status were also confirmed in a subgroup of 107 patients found negative for BRCA1 exon 11 mutations. CONCLUSIONS Our data suggest that BRCA1 methylation determines the earlier onset of HGSOC. Furthermore our study supports the idea that BRCAness is not only due to mutations but also to epigenetic changes in BRCA1 promoter gene.

Expression of epithelial cell adhesion molecule in paired tumor samples of patients with primary and recurrent serous ovarian cancer.

Objective Ovarian cancer (OC) recurrence constitutes a therapeutic dilemma with various novel targeted agents emerging that offer alternative treatment options. The aim of the present study was to evaluate and compare epithelial cell adhesion molecule (EpCAM) expression profiles in paired tumor samples of patients with OC relapse. Methods EpCAM expression was analyzed by immunohistochemistry using the avidin-biotin-complex method on paraffin-embedded OC tissues obtained at primary surgery as well as on corresponding tumor samples of the same patients at relapse. The EpCAM overexpression was defined as 76% to 100% of tumor cells positively stained for EpCAM. Clinical data were collected within the Tumorbank Ovarian Cancer Network. Results Nineteen patients with serous OC histology were included in the study (median age at primary diagnosis, 50 years; range, 40–74 years). The majority of the patients (95%) presented with International Federation of Gynecology and Obstetrics stage III/IV, and 68.4% of the tumors were poorly differentiated. A complete macroscopic tumor resection could be achieved in 15 patients (78.9%) at diagnosis. Epithelial cell adhesion molecule overexpression was detected in 17 (89%) of the primary and 16 (84%) of the recurrent tumors (P = 1.0); hence, no significant change of the EpCAM expression profile could be identified over time. Conclusions Epithelial cell adhesion molecule expression profile appears to remain stable during the course from the primary throughout the relapse of serous OC. The results indicate that EpCAM might be an interesting therapeutic target structure in serous OC.

Preoperative CA-125 Value as a Predictive Factor for Postoperative Outcome in First Relapse of Platinum-sensitive Serous Ovarian Cancer

Aim: The purpose of the study was to evaluate whether preoperative cancer antigen 125 (CA-125) levels predict outcome of secondary cytoreductive surgery (SCS) in patients with serous recurrent ovarian cancer and whether this could be used as a prognostic factor for progression-free (PFS) and overall (OS) survival. Patients and Methods: A cohort of 111 patients with first recurrence of platinum-sensitive serous ovarian cancer, who had undergone SCS at the Department of Gynecology and Oncological Surgery, Charité, Campus Virchow Clinic was analyzed in correlation with the preoperative CA-125 value. Results: The median preoperative CA-125 level was 164 U/ml. Complete tumor resection was achieved in 58.6% of the patients. PFS and OS for patients with preoperative CA-125 of less than 164.5 U/ml was significantly better than those with preoperative CA-125 ≥164.5 U/ml (p=0.025 and p<0.001, respectively). Conclusion: Preoperative CA-125 is not a statistically significant predictive factor for complete tumor resection after SCS. Preoperative CA-125 <164.5 U/ml can predict significantly better PFS and OS for patients with first recurrence of platinum-sensitive ovarian cancer.

Impact of BRCA1 gene alterations on tumor characteristics and clinical outcome in ovarian cancer (OC) patients.

5019 Background: Patients (pts) with BRCA1-associated OC appear to have a survival advantage over those with sporadic OC. It is unclear if this is due to a greater platinum sensitivity or due to a ...