Atanas Ignatov

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Tamoxifen is the most frequently used anti-hormonal drug for treatment of women with hormone-dependent breast cancer. The aim of this study is to investigate the mechanism of tamoxifen resistance and the impact of the new estrogen G-protein coupled receptor (GPR30). MCF-7 cells were continuously exposed to tamoxifen for 6 months to induce resistance to the(More)
AIMS We wanted to assess the factors that predict complications and patient satisfaction of totally implanted central venous access ports (TIAP). METHODS We reviewed 550 patients with breast or gynaecological malignancies who had initial port placement for chemotherapy between 1995 and 2006. We retrospectively assessed all TIAP complications, port(More)
OBJECTIVE This study was undertaken to evaluate the potential role of G-protein-coupled estrogen receptor in endometrial pathology associated with tamoxifen treatment of breast cancer patients. STUDY DESIGN We investigated whether G-protein-coupled estrogen receptor plays a role in mediating proliferating effect of tamoxifen in endometrial carcinoma(More)
To determine the impact of adjuvant treatment with tamoxifen and aromatase inhibitors (AI) on the survival of men with breast cancer. We analyzed 257 male patients with hormone-receptor-positive breast cancer from numerous German population-based cancer registries treated with tamoxifen (N = 207) or aromatase inhibitors (N = 50). The median follow-up was(More)
Recently, we have shown that the new G-protein-coupled estrogen receptor GPR30 plays an important role in the development of tamoxifen resistance in vitro. This study was undertaken to evaluate the correlation between GPR30 and tamoxifen resistance in breast cancer patients. GPR30 protein expression was evaluated by immunohistochemical analysis in 323(More)
INTRODUCTION The aim of this study was to determine the efficacy of ultrasonography (US)-guided excision of palpable breast cancer and to compare it with the standard palpation-guided breast-conserving surgery (BCS). METHODS For this purpose, 335 women with palpable breast cancer who underwent BCS were retrospectively studied. The positive surgical(More)
OBJECTIVE The aim of this study was to investigate the role of p16 in tumorigenesis of endometrial carcinoma (EC). METHODS Expression of p16 protein was analyzed using immunohistochemistry. The methylation status of p16 promoter region was determined by methylation-specific PCR. Deletion analysis of the p16 gene was performed by PCR-analyses. RESULTS(More)
Elevated platelet count occasionally is associated with gynecologic malignancies. We investigated the level of platelet count in 450 patients with gynecologic tumors. Ovarian cancer patients have increased platelet count associated with the course of treatment and disease progression. In multivariate analysis, the decrease of platelet count less than 25%(More)
Overexpression of human epidermal growth factor receptor 2 (HER2) is an important prognostic and predictive marker of response to anti-HER2 therapy in breast cancer. Our goal was to analyze the prognostic significance of moderate expression of HER2 in breast cancer with intermediate differentiation grade. We performed a multicenter retrospective register(More)
The aim of the current study was to investigate the role of BRCA1 gene aberrations in sporadic triple-negative breast cancer (TNBC) and its impact on anthracycline-based therapy. BRCA1 promoter methylation was analyzed in 70 TNBC and compared with the clinical and pathologic characteristics. As a control group, we used 70 patients with non-TNBC. BRCA1(More)