Araştırma Çıktıları | TR-Dizin | WoS | Scopus | PubMed
Permanent URI for this communityhttps://hdl.handle.net/11727/4806
Browse
8 results
Search Results
Item Treatment Outcomes of Breast Cancer Liver Metastasis Treated with Stereotactic Body Radiotherapy(2018) Onal, Cem; Guler, Ozan Cem; Yildirim, Berna Akkus; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0001-6661-4185; 30296648; HOC-5611-2023; AAC-5654-2020; V-5717-2017Background: To assess the outcomes of breast cancer liver metastasis (BCLM) treated with stereotactic body radiotherapy (SBRT) and systemic treatment. Materials and methods: Patients with oligometastasis at the time of liver metastasis (LM) or who became oligometastatic (<= 5 metastases) after systemic treatment were assessed. Twenty-nine liver metastatic lesions were treated with a total of 54 Gy delivered in 3 fractions. The local control (LC), overall survival (OS), and progression-free survival (PFS) rates were calculated using Kaplan-Meier analyses. Results: A total of 22 patients with 29 liver metastatic lesions treated with liver SBRT between April 2013 and September 2017 were retrospectively analyzed. After a median follow-up time of 16.0 months (range 4.4-59.4 months), 18 patients (82%) had disease recurrence, median of 7.4 months (range 1.0-27.9 months) after completion of liver SBRT. The 1- and 2-year OS rates were 85% and 57%, and the 1- and 2-year PFS rates were 38% and 8%, respectively. The 1- and 2-year LC rates were 100% and 88%, respectively. No significant prognostic factors, including disease extension, size of metastasis, number of liver metastasis and timing of liver metastasis, hormonal status affecting OS, PFS and LC were found. No patients experienced Grade 4 or 5 toxicity; furthermore, only one patient experienced rib fracture 6 months after completion of treatment, and one patient had a duodenal ulcer. Conclusion: This study is the first to evaluate the feasibility of SBRT to BCLM patients. Liver SBRT is a conservative approach with excellent LC and limited toxicities. (C) 2018 Elsevier Ltd. All rights reserved.Item Association of Tumor Strain Ratio with Prognostic Factors in Invasive Breast Cancer(2022) Karan, Belgin; Purbager, Aysin; https://orcid.org/0000-0002-7034-7806We evaluate the correlations between tumor strain ratio value and prognostic factors for breast cancers. Fifty-seven women with invasive breast cancer underwent ultrasound elastography prior to surgery. Elastography strain ratio (SR), defined as the fat-to-lesion ratio, was recorded for each lesion using the software in the ultrasound equipment. We evaluated the associations between tumor SR and pathological prognostic factors such as tumor subtype, tumor size, axillary lymph node metastasis, histological grade, vascular invasion, and hormonal receptor status. We found a significant correlation between tumor SR and progesterone receptor (PR) status (p = 0.02). Tumors with axillary lymph node metastasis had a higher SR value than those without lymph node metastasis; however, this difference was not significant. Strain elastography revealed that grade 3 tumors had softer tissues than grade 1 and 2 tumors, although this was not statistically significant. The tumor SR value was not significantly correlated with tumor subtypes, tumor size, vascular invasion, and estrogen receptor or cell surface human epidermal growth factor 2 status (p > 0.05). The present study demonstrated no significant correlation between SR values and prognostic factors, except for PR status. However, tumors with LN metastasis tended to exhibit greater stiffness, and higher grade tumors exhibited lower stiffness owing to necrosis. Further studies with large study population on tumor-associated stiffness are required.Item Significance of liver metastasis volume in breast cancer patients treated with stereotactic body radiotherapy(2021) Oymak, Ezgi; Guler, Ozan Cem; Onal, Cem; 0000-0002-2742-9021; 34477885; AGG-9214-2022; D-5195-2014Purpose This study analyzed the impact of liver metastasis (LM) volume on treatment outcomes in breast cancer (BC) patients treated with stereotactic body radiotherapy (SBRT). Methods This single-institution retrospective analysis included 40 oligometastatic (<= 5 metastases) BC patients with 58 liver metastases treated with SBRT between April 2013 and March 2021. The prognostic factors for local control (LC), overall survival (OS), and progression-free survival (PFS) rates were assessed. Results Median follow-up time was 28.1 months. Isolated and solitary LM were seen in 26 (65%) and 24 (60%) patients, respectively. Median time to disease recurrence was 10.7 months post liver SBRT. The 2-year OS, PFS, and LC rates were 71.4%, 27.5%, and 86.8%, respectively. In univariate analysis, patients with a gross tumor volume (GTV) of <= 6 cc and a planning target volume (PTV) of <= 38 cc demonstrated a significantly better median OS than those with GTV > 6 cc and PTV > 38 cc. In multivariate analysis, the predictive factors for worse OS were GTV > 6 cc (HR = 3.07 [95% CI, 1.14-8.22; p = 0.03]) and PTV > 38 cc (HR = 5.91 [95% CI, 1.92-18.21; p = 0.002]). No significant factor for PFS was found. Only 2 patients experienced rib fracture at 4 and 6 months post treatment, and 1 patient had a grade II duodenal ulcer. Conclusion Liver SBRT is an effective and safe treatment option for oligometastatic BC patients with excellent LC, promising survival, and limited toxicity. Patients with smaller tumors displayed better OS than their counterparts, validating the effectiveness of a local treatment for this group.Item Kinome-wide RNAi screening for mediators of ABT-199 resistance in breast cancer cells identifies Wee1 as a novel therapeutic target(2021) Aka, Yeliz; Acikbas, Ufuk; Kutuk, Ozgur; 34171479Antiapoptotic and proapoptotic BCL-2 protein family members regulate mitochondrial apoptotic pathway. Small molecule inhibitors of antiapoptotic BCL-2 proteins including BCL-2-specific inhibitor ABT-199 (Venetoclax) are in clinical development. However, the efficiency of ABT-199 as a single agent in solid tumors is limited. We performed a high-throughput RNAi kinome screen targeting 691 kinases to identify potentially targetable kinases to enhance ABT-199 response in breast cancer cells. Our studies identified Wee1 as the primary target kinase to overcome resistance to ABT-199. Depletion of Wee1 by siRNA-mediated knockdown or inhibition of Wee1 by the small molecule Wee1 inhibitor AZD1775 sensitized SKBR3, MDA-MB-468, T47D and CAMA-1 breast cancer cells to ABT-199 along with decreased MCL1. BH3-only proteins PUMA and BIM functionally contribute to apoptosis signaling following co-targeting BCL-2 and Wee1. Suppression of Wee1 function increased mitochondrial cell death priming. Furthermore, we found that Wee1 inhibition altered MCL1 phosphorylation and protein stability, which led to HUWE1-mediated MCL1 degradation. Our findings suggest that Wee1 inhibition can overcome resistance to ABT-199 and provide a rationale for further translational investigation of BCL-2 inhibitor/Wee1 inhibitor combination in breast cancer.Item Associations between the expression of mucins (MUC1, MUC2, MUC5AC and MUC6) and clinicopathologic parameters of human breast carcinomas(2020) Oral, Onur; Unverdi, Hatice; Kumcu, Emrah; Turkbey, Duygu; Dogan, Serdar; Hucumenoglu, Sema; 33154304Aims: The aim of this study is to evaluate the relationships between the expression of mucins in invasive breast carcinomas and clinicopathologic parameters. Materials and Methods: We examined 150 cases of invasive breast carcinoma, using the 2012 World Health Organization (WHO) classification of the tumors of the breast. We studied the expression of MUC1, MUC2, MUC5AC, and MUC6 by immunohistochemistry. We also evaluated normal breast tissue and ductal carcinoma in situ (DCIS) lesions in nearby invasive tumor areas. Results: In invasive breast carcinomas, MUC1, MUC2, MUC5AC, and MUC6 were expressed in 98.6%, 11.3%, 9.9, and 8.5% of cases, respectively. MUC2, MUC5AC, and MUC6 were overexpressed in invasive tumors and DCIS lesions were compared with normal breast tissue. The apical pattern of MUC1 was correlated with low grade and ER expression. MUC2 was correlated with mucinous carcinoma and an inverse association with invasive ductal carcinoma, not otherwise specified (NOS). MUC6 expression was associated with lymphovascular invasion. Conclusions: Most invasive breast tumors express MUC1 and the apical pattern of MUC1 is correlated with low grade and ER expression. MUC6 expression is associated with indicators of poor prognosis. Further comprehensive studies need to evaluate the role of mucins as a potential biomarker and to be used as a specific therapeutic target against breast cancer.Item Radiotherapy After Skin-Sparing Mastectomy and Implant-Based Breast Reconstruction(2019) Sari, Sezin Yuce; Guler, Ozan Cem; Gultekin, Melis; Yildirim, Berna Akkus; Onal, Cem; Ozyigit, Gokhan; Yildiz, Ferah; 0000-0001-6908-3412; 31255547; AAC-5654-2020We aimed to evaluate the cosmetic results of radiotherapy in 170 breast cancer patients after implant-based reconstruction. Cosmetic results were excellent or fair in most patients after radiotherapy. However, bolus use, lymphatic irradiation, and the volume receiving at least 110% of the prescribed dose being >1% significantly deteriorated the outcomes. Introduction: We evaluated the cosmetic results of radiotherapy (RT) after implant-based reconstruction (IBR). Patients and Methods: We retrospectively evaluated 170 patients with 171 breast cancers treated between December 2004 and January 2016 in 2 university hospitals. RT fields were reconstructed breast (RB) only in 24 (14%), and RB and regional lymphatics in 147 (86%) breasts, respectively. All but 1 patient received a total 50 Gy with conventional fractionation. All patients received systemic chemotherapy. One hundred thirty-eight (81%) patients received hormonal therapy; 118 tamoxifen and 20 aromatase inhibitor. Results: Median follow-up time was 46.8 months (range, 1-163 months). The 5-year disease-free and overall survival rate was 83% and 93%, respectively. Cosmetic results were considered excellent in 111 (65%), fair in 46 (27%), and bad in 14 (8%) RB by patients. Thirty-four (20%) RB had restorative surgery; because of surgeons' preference because of implant natural life time span in 5, and contracture, fibrosis, deformation, or dislocation of the implant, or cellulitis in the remaining. Statistically significant adverse factors in univariate analysis for impaired cosmetic outcome were bolus use on the RB, lymphatic irradiation, and volume that received at least 110% of the prescribed dose being >1%. The use of bolus material was the only prognostic factor for deterioration of the cosmetic result in multivariate analysis. Conclusion: RT after IBR yields acceptable cosmetic results. Although only 111 (65%) of RBs were considered to have excellent cosmetic results, only a small percentage of patients needed reoperation because of bad cosmetic outcome. (C) 2019 Elsevier Inc. All rights reserved.Item Diagnostic Accuracy of Axillary Ultrasound in Early-Stage Breast Cancer(2019) Yilmaz, Tugba Han; Yerli, Hasan; Arslan, Baha; Erol, Varlik; Gulay, HuseyinSentinel lymph node biopsy is the standard application for evaluating the axilla in patients with breast cancer. The Z0011 trial conducted by The American College of Surgeons Oncology Group (ACOSOG) revealed that axillary dissection may be redundant in selected patients with positive sentinel node. This raises questions regarding the application of this result to ultrasound-positive patients. This research therefore aimed to evaluate how accurate an ultrasound scan is for axillary node status in early-stage breast carcinoma. The study included 156 newly diagnosed clinical T1-T2, N0 breast cancer patients attending our breast clinic between January 2010 and February 2016. Sentinel lymph node biopsy and axillary lymph node clearance in the presence of sentinel lymph node metastasis was performed on all the breast cancer patients. Axillary ultrasound reports were reviewed retrospectively and the results compared with surgical pathology results. The sensitivity and specificity of axillary ultrasound for detecting axillary lymph node disease was 69.2% and 98%, respectively, with a negative predictive value of 86.4% and positive predictive value of 94.7%. Given the high sensitivity and specificity, and high positive predictive value and negative predictive value demonstrated in the present study, axillary ultrasound represents a potential alternative to sentinel lymph node biopsy for staging of the axilla in early breast cancer. Subsequent trials (SOUND) comparing axillary ultrasound alone with sentinel lymph node biopsy in early breast cancer patients will provide additional information about the subject.Item Does Marital Adjustment Mediate Type C Personality-Depressive Symptoms Relation? A Comparison between Breast Cancer Patients and Cancer-Free Women(2019) Bozo, Ozlem; Ar, Yagmur; Eldogan, DilayThe purpose of this study was to investigate the relation between Type C personality and depressive symptoms in breast cancer patients, and to examine if marital adjustment mediates this relation. The data was collected from 98 married breast cancer patients undergoing post-operative chemotherapy treatment. Also, 97 married cancer-free women were included in the study as the comparison group to test whether the proposed relationship is typical only to breast cancer patients. Regression analyses indicated that marital adjustment partially mediated Type C personality-depressive symptoms relation in breast cancer patients. However, this mediation was not found in cancer-free women. Findings of the study were discussed in relation to current literature and cultural context of Turkey.