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Öğe Breast Conserving Surgery and Sentinel Lymph Node Biopsy in Locally Advanced Breast Cancer: Single Center Experience(Galenos Publ House, 2011) Sezer, Atakan; Alas, Rusen Cosar; Cicin, Irfan; Hoscoskun, Zeki; Tuncbilek, NerminObjective: Patients with locally advanced breast cancer may undergo breast conserving surgery after neoadjuvant chemotherapy. The aim of the study is to evaluate the results of locally advanced breast cancer patients who underwent breast conserving surgery, axillary dissection and sentinel lymph node biopsy in a single center. Material and Methods: 12 patients with locally advanced breast cancer stage IIIA/IIIB were included in the study between 2002-2009. The patients were given anthracycline-based regimen before surgery. Patients underwent breast conserving surgery, axillary dissection, and sentinel lymph node biopsy followed by radiotherapy. Results: There were five patients in stage IIIA, six in stage IIIB, and one in stage IIIC. Patients had received 3-6 regimen of FAC/FEC. Eight had partial and four had complete response. Five positive axilla were detected. The median value of the lymph nodes was 12 (n:8-19). Five patients underwent sentinel lymph node biopsy. The biopsy has failed in one patient and the median value of dissected sentinel node was 3.5 (n:3-4). Locoregional recurrence was not observed in any patients. The mean follow-up of the patients was 29.8 months and median time was 16 (n:2-80) months. Of the 12 patients 10 are alive and 2 were deceased. Conclusion: In selected locally advanced patients, breast conserving surgery and sentinel lymph node biopsy may be applied by a multidisciplinary approach, and excellent success may be achieved in those patients as in early breast cancer patients.Öğe Developing and comparing two different prognostic indexes for predicting disease-free survival of nonmetastatic breast cancer patients(Tubitak Scientific & Technological Research Council Turkey, 2011) Tokatli, Zehra Fusun; Ture, Mevlut; Omurlu, Imran Kurt; Alas, Rusen Cosar; Uzal, Mustafa CemAim: To determine 2 different prognostic indexes (PI) for the differentiation of subgroups of nonmetastatic breast cancer patients with the Cox regression analysis and survival tree (ST) methods and the additional usage of the Kaplan-Meier estimates to investigate the predictive power of these methods. Materials and methods: Prognostic factors data were collected for 410 patients. The Cox regression analysis examines the relationship of the survival distribution and covariates. The ST method is a tree-structured survival analysis based on a recursive partitioning algorithm. In this study, Harrell's concordance indexes of models for training and test sets were computed. Furthermore, survival curves were estimated by the Kaplan-Meier method. Disease-free survival (DFS) was calculated from the time of initial diagnosis (initiation of the first treatment) to the first recurrence of disease. Results: After a median follow-up of 48 months, 100 (24.4%) patients have had at least 1 of the DFS events. In Cox regression analysis, we proposed the simple PI, which is a sum of axillary nodal and HER2/neu status. In the ST method, we identified 3 variables: HER2/neu, axillary nodal, and estrogen receptor status. The axillary nodal status was the most important determining factor for recurrence. Conclusion: We found that the PI of the ST and Cox regression methods had similar performance levels in predicting DFS, and the error rates of the models were close to each other in the training and test sets. Furthermore, we determined that the axillary nodal status and HER2/neu were the most important determining factors for prediction of DFS in breast cancer patients.Öğe The Effect of Positional Movement of a Semiflexible Applicator on Dose Distrubutions in Low Dose Rate Brachytherapy for Cervical Carcinoma(Ortadogu Ad Pres & Publ Co, 2010) Kucucuk, Seden; Kemikler, Gonul; Okutan, Murat; Aslay, Isik; Disci, Rian; Alas, Rusen Cosar; Tore, GokhanObjective: Current study aims to detect the movements of a semiflexible applicator (TORE's applicator) in the first 24 hours and to analyze its effect on the calculated point A, bladder and rectum doses in low dose rate brachytherapy (LDR-BT) applications. Material and Methods: Eighty films were evaluated on 18 cervical carcinoma patients (20 applications) who were treated with curative radiotherapy. The comparison of the reference points and doses at critical organs were performed by using a reference axis which was fixed to bony landmarks in the pelvis. To evaluate the movement of the applicator, distance of the upper point and lower point of the tandem to the reference axis were measured. Additionally, the angular deviation of the applicator was tested. Results: The movements of the upper point and lower point of the tandem in x, y, z axes were 5.30 +/- 6.33 mm, 2.80 +/- 2.24 mm, 6.65 +/- 8.33 mm and 3.45 +/- 4.32 mm, 3.75 +/- 3.59 mm, 3.05 +/- 3.08 mm, respectively. The mean differences were 3.30 +/- 2.99 degrees in alpha-angle and 5.65 +/- 4.76 degrees in beta-angle. The mean percent dose changes in point A, bladder and rectum were 1.5 +/- 1.2%, 3.7 +/- 3.1%, 4.4 +/- 4.0%, respectively. Conclusion: Our study demonstrates that there are some movements of the applicator during LDR-BT, however these movements do not result in significant dose changes in target volumes and critical organs. Therefore, positional correction is not required. In conclusion, CT-compatible TORE's applicator that allows an advantage for CT-based 3D planning is useful and safe for brachytherapy.Öğe Identification of patients who may benefit from the prophylactic cranial radiotherapy among breast cancer patients with brain metastasis(Springer, 2009) Saip, Pinar; Cicin, Irfan; Eralp, Yesim; Karagol, Hakan; Kucucuk, Seden; Alas, Rusen Cosar; Yavuz, EkremBackground To identify the candidates for prophylactic cranial radiotherapy (PCI) among the patients with early and advanced-stage breast cancer. Methods The demographic, pathologic and clinical features and survival results of 182 brain metastatic breast cancer patients treated with cranial radiotherapy were examined. Results Early stage patients who progressed with isolated brain metastasis had longer survival (13 months vs. 4 months P = 0.006). Lobular/mixed type histology (P = 0.033), high nuclear (P = 0.046) and high histological grade (P = 0.034) were the prognostic factors for isolated brain metastases. The most significant factor for the time to brain metastasis was the number of involved of lymph nodes (P = 0.004). In 60% of 148 patients with metastatic breast cancer, a progression with isolated brain metastasis was developed while the systemic disease was under control. Isolated brain metastasis progression was related to the presence of the hepatic metastasis at the first relapse (P = 0.001) and with ErbB-2 overexpression (P = 0.034). The time to the brain metastasis from the first extracerabral metastasis was associated with the high nuclear grade (P = 0.040) and with chemoresistance (P = 0.037). The median survival time after the brain metastases in chemosensitive patients was longer than in chemoresistant patients (8 months vs. 3 months P = 0.044). In chemoresistant patients (P = 0.0028) and/or in triple negative patients (P = 0.05) the development of the brain metastasis was early and the survival after brain metastasis was short. Discussions Since there is a tendency to early brain metastasis in early stage patients with high-grade, lobular/mixed type histology tumors and with a high number of involved lymph nodes, the value of PCI can be explored in these patients by a well designed prospective trial. Advanced stage chemosensitive patients with ErbB-2 over-expression and/or with hepatic metastasis at their first relapse may be candidates for PCI. There is no place for PCI in chemoresistant and triple-negative breast cancer patients.Öğe Primary unknown solitary brain metastasis: brain recurrence alone(Kare Publ, 2007) Bayir Angin, Goden; Saynak, Mert; Kocak, Zafer; Ozen, Alaattin; Alas, Rusen Cosar; Caloglu, Vuslat Yurut; Caloglu, MuratA 53-year-old male patient presented with complaints of headache and paresis in left arm. Cranial computerized tomography and magnetic resonance imaging (MRI) demonstrated a mass in the right parietal region. The solitary tumor was removed by craniotomy. Histological examination showed that it was a squamous cell carcinoma metastasis. The patient subsequently underwent whole brain radiotherapy for a total dose of 30 Gy in 10 fractions and conventional external-beam boost irradiation of 10 Gy in 5 fractions to the tumor margins. He remained disease free until 23 months later. He returned to our clinic with left arm paresis after 24 months. In the left parietal lobe a new lesion was determined on his MRI scan. Partial brain reirradiation at a dose of 25 Gy in 10 fractions was performed. There was a partial regression of symptoms after radiotherapy. In the light of this patient, we reviewed the literature and discussed the treatment strategies of patients with solitary brainmetastasis.
