Maktav Dincer
Istanbul University
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Publication
Featured researches published by Maktav Dincer.
British Journal of Radiology | 2010
Gül Alço; S I Iğdem; Tülay Ercan; Maktav Dincer; R Şentürk; S Atilla; F Oral Zengin; S. Okkan
The aim of this study is to evaluate the coverage of axillary nodal volumes with high tangent fields (HTF) in breast radiotherapy and to determine the utility of customised blocking. The treatment plans of 30 consecutive patients with early breast cancer were evaluated. The prescription dose was 50 Gy to the whole breast. Axillary level I-II lymph node volumes were delineated and the cranial border of the tangential fields was set just below the humeral head to create HTF. Dose-volume histograms (DVH) were used to calculate the doses received by axillary nodal volumes. In a second planning set, HTF were modified with multileaf collimators (MLC-HTF) to obtain an adequate dose coverage of axillary nodes. The mean doses of the axillary nodes, the ipsilateral lung and heart were compared between the two plans (HTF vs MLC-HTF) using a paired sample t-test. The doses received by 95% of the breast volumes were not significantly different for the two plans. The doses received by 95% of the level I and II axillary volumes were 16.79 Gy and 11.59 Gy, respectively, for HTF, increasing to 47.2 Gy and 45.03 Gy, respectively, for MLC-HTF. Mean lung doses and per cent volume of the ipsilateral lung receiving 20 Gy (V20) were also increased from 6.47 Gy and 10.47%, respectively, for HTF, to 9.56 Gy and 16.77%, respectively, for MLC-HTF. Our results suggest that HTF do not adequately cover the level I and II axillary lymph node regions. Modification of HTF with MLC is necessary to obtain an adequate coverage of axillary levels without compromising healthy tissue in the majority of the patients.
American Journal of Clinical Oncology | 2003
Kazim Uygun; Adnan Aydiner; Pinar Saip; Mert Basaran; Faruk Tas; Zafer Kocak; Maktav Dincer; Erkan Topuz
Adult granulosa cell tumors of the ovary are rare neoplasms, accounting for less than 5% of all ovarian malignancies. In addition to the tumor stage, residual disease, patient age, tumor size, extent of surgery, and also some histologic factors have been reported to be of prognostic importance. Tumor registries were screened for all patients treated between 1979 and 1998 for ovarian tumors at the University of Istanbul. There were 952 ovarian carcinomas, of which 47 were granulosa cell tumors. All charts were reviewed, and the clinical data were extracted. Prognostic factors and treatment results were evaluated retrospectively. The median follow-up was 84 (range: 6–141 months) months. According to univariate analysis, there were only two significant factors for overall survival (OS): stage and presence of residual disease. The OS of the 23 patients with early stage (mean, 122 months; median, unreached) was significantly (p = 0.0001) better than the OS of the 22 patients with advanced stage (mean, 34 months; median, 21 months). A significant difference (p = 0.0004) in OS was also observed between patients with residual (mean, 42 months; median, 21 months) and nonresidual (mean, 108 months; median, unreached) disease. In a multivariate analysis, only stage remained statistically significant (p = 0.0001). The overall 5-year survival rate was 55% and median survival after recurrence was 21 months. Despite the small number of patients, the study showed that stage and macroscopic residual disease are significant prognostic factors. The benefit of chemotherapy and radiotherapy remains controversial.
Japanese Journal of Radiology | 2010
Tülay Ercan; Şefik İğdem; Gül Alço; Funda Zengin; Selin Atilla; Maktav Dincer; S. Okkan
PurposeThe aim of this study was to be able to implement the field-in-field intensity-modulated radiotherapy (FiF) technique in our daily practice for breast radiotherapy. To do this, we performed a dosimetric comparison.Materials and methodsTreatment plans were produced for 20 consecutive patients. FiF plans and conformal radiotherapy (CRT) plans were compared for doses in the planning target volume (PTV), the dose homogeneity index (DHI), doses in irradiated soft tissue outside the target volume (SST), ipsilateral lung and heart doses for left breast irradiation, and the monitor unit counts (MU) required for treatment. Averaged values were compared using Student’s t-test.ResultsWith FiF, the DHI is improved 7.0% and 5.7%, respectively (P < 0.0001) over the bilateral and lateral wedge CRT techniques. When the targeted volumes received 105% and 110% of the prescribed dose in the PTV were compared, significant decreases are found with the FiF technique. With the 105% dose, the SST, heart, and ipsilateral lung doses and the MU counts were also significantly lower with the FiF technique.ConclusionThe FiF technique, compared to CRT, for breast radiotherapy enables significantly better dose distribution in the PTV. Significant differences are also found for soft tissue volume, the ipsilateral lung dose, and the heart dose. Considering the decreased MUs needed for treatment, the FiF technique is preferred over tangential CRT.
Ejso | 1997
Sidika Kurul; Maktav Dincer; Ahmet Kizir; Adnan Uzunismail; Emin Darendeliler
Reconstructive surgery in previously irradiated areas is more difficult than in non-irradiated cases. A retrospective analysis of the outcome of 200 previously irradiated patients who had skin graft or flap reconstruction performed by the same surgeon is presented, and the most suitable surgical technique in irradiated areas is discussed. One hundred and fifty-six patients had skin and oral cavity cancer, and were operated on after local recurrence. Twenty patients had breast cancer; 15 were operated on for local recurrence and five for breast reconstruction. Twenty-four patients had soft tissue sarcomas. Eighty-five patients had a skin graft (group 1), 35 had a skin flap (group 2), 10 had a fascia/muscle flap plus skin graft and 70 had a myocutaneous flap (group 3). Analysis of complications revealed statistically significant differences in terms of incomplete graft/flap necrosis between group 1 and 2 (P < 0.001) and groups 1 and 3 (P < 0.001), and in terms of infection between groups 1 and 3 (P < 0.01). We conclude that the method of reconstruction is determined by the characteristics of the defect such as size and localization; the quality, fractionation, total dose, and energy of radiation used; skin and subcutaneous tissue changes due to radiation; and operation time. However, it is reasonable to choose fascia/muscle or myocutaneous flaps for reconstruction in previously irradiated areas. These methods are more resistant to bacterial inoculation, more prone to clean residual infection, and provide better vascularized tissue and volume replacement for contour defects.
Acta Oncologica | 1994
Adnan Aydiner; Erkan Topuz; Rian Discli; Vildan Yasasever; Maktav Dincer; Koray Dinçol; Nijad Bilge
For the diagnosis of bone metastasis in breast cancer patients during systemic treatment serum tumor markers, including carbohydrate antigens 15-3 (CA 15-3) and 19-9 (CA 19-9), cancer antigen 125 (CA 125), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), beta-2 microglobulin (BMG), ferritin, and tissue polypeptide antigen (determined by the M3 monoclonal antibody, TPS) were measured in 22 patients with known bone metastases and in 30 patients without documented metastases. The most useful single marker was CA 15-3. By stepwise discriminant analysis, it was found that 90% of the patients could be diagnosed truly by using the markers CA 15-3, BMG and ferritin. It is concluded that monitoring with combinations of tumor markers at regular intervals increases the diagnostic efficiency.
Asian Pacific Journal of Cancer Prevention | 2014
Gül Alço; Sefik Igdem; Maktav Dincer; Vahit Ozmen; Sezer Saglam; Derya Selamoglu; Zeynep Erdogan; Cetin Ordu; Sedef Yenice; Coskun Tecimer; Gokhan Demir; Gülistan Köksal; S. Okkan
BACKGROUND Vitamin D deficiency is a potentially modifiable risk factor that may be targeted for breast cancer (BC) prevention. It may also be related to prognosis after diagnosis and treatment. The aim of our study was to determine the prevalence of vitamin D deficiency as measured by serum 25-hydroxy vitamin D (25-OHD) levels in patients with BC and to evaluate its correlations with life-style and treatments. MATERIALS AND METHODS This study included 186 patients with stage 0-III BC treated in our breast center between 2010-2013. The correlation between serum baseline 25-OHD levels and supplement usage, age, menopausal status, diabetes mellitus, usage of bisphosphonates, body-mass index (BMI), season, dressing style, administration of systemic treatments and radiotherapy were investigated. The distribution of serum 25-OHD levels was categorized as deficient (<10ng/ ml), insufficient (10-24 ng/ml), and sufficient (25-80 ng/ml). RESULTS The median age of the patients was 51 years (range: 27-79 years) and 70% of them had deficient/insufficient 25-OHD levels. On univariate analysis, vitamin D deficiency/insufficiency was more common in patients with none or low dose vitamin D supplementation at the baseline, high BMI (≥25), no bisphosphonate usage, and a conservative dressing style. On multivariate analysis, none or low dose vitamin D supplementation, and decreased sun-exposure due to a conservative dressing style were found as independent factors increasing risk of vitamin D deficiency/insufficiency 28.7 (p=0.002) and 13.4 (p=0.003) fold, respectively. CONCLUSIONS The prevalence of serum 25-OHD deficiency/insufficiency is high in our BC survivors. Vitamin D status should be routinely evaluated for all women, especially those with a conservative dressing style, as part of regular preventive care, and they should take supplemental vitamin D.
Ejso | 2015
Vahit Ozmen; Beyza Ozcinar; Atilla Bozdogan; Yesim Eralp; Ekrem Yavuz; Maktav Dincer
BACKGROUND The role of internal mammary lymph node biopsy (IMLNB) is still being discussed in breast cancer treatment. The aim of this study was to investigate the role of IMLNB on adjuvant therapy and survival of patients with breast cancer. PATEINTS AND METHODS The data of 72 patients with clinically negative axilla and IMLNB were evaluated. IMLNB was performed either through a small separate intercostal incision or from the same incision for tumor resection or mastectomy by using both blue dye and radioisotope. Pathological analysis was performed on formalin-fixed paraffin-embedded tissues. RESULTS Ten of the patients (14%) were IMLNB-positive. The axillary sentinel lymph node and IMLN were negative in most of the patients (52.8%). In one patient (1.4%), the axilla was negative but the IMLNB was positive. IMLNB changed the pathologic stage in eight patients (11%). Adjuvant internal mammary radiotherapy was added to the treatment protocol for 10 patients due to IMLNB positivity and adjuvant chemotherapy was added in for only one patient with negative axilla. The factors found to be related with IMLN positivity were SLN positivity (p = 0.033), mastectomy (p = 0.022), and the number of resected IMLN ≥2 (p = 0.040). The median follow-up time was 115.5 months (range, 30-162 months). The ten-year overall survival (OS) rate was 86%. Systemic metastasis (p = 0.007), SLNB positivity (p < 0.001), and IMLNB positivity (p = 0.005) were statistically related to overall survival. CONCLUSION IMLNB positivity in patients with breast cancer changed the pathologic stage and adjuvant treatment modalities of patients and also adversely affected the overall survival.
Oncology Letters | 2015
Gül Alço; Atilla Bozdogan; Derya Selamoglu; Kezban Nur Pilanci; Sitki Tuzlali; Cetin Ordu; Sefik Igdem; S. Okkan; Maktav Dincer; Gokhan Demir; Vahit Ozmen
The aim of the present study was to identify the optimal Ki-67 cut-off value in breast cancer (BC) patients, and investigate the association of Ki-67 expression levels with other prognostic factors. Firstly, a retrospective search was performed to identify patients with stage I–III BC (n=462). A range of Ki-67 index values were then assigned to five groups (<10, 10–14, 15–19, 20–24 and ≥25%). The correlation between the Ki-67 index and other prognostic factors [age, tumor type, histological and nuclear grade, tumor size, multifocality, an in situ component, lymphovascular invasion (LVI), estrogen and progesterone receptor (ER/PR) expression, human epidermal growth factor receptor (HER-2) status, axillary involvement and tumor stage] were investigated in each group. The median Ki-67 value was revealed to be 20% (range, 1–95%). A young age (≤40 years old), tumor type, size and grade, LVI, ER/PR negativity and HER-2 positivity were revealed to be associated with the Ki-67 level. Furthermore, Ki-67 was demonstrated to be negatively correlated with ER/PR expression (P<0.001), but positively correlated with tumor size (P<0.001). The multivariate analysis revealed that a Ki-67 value of ≥15% was associated with the largest number of poor prognostic factors (P=0.036). In addition, a Ki-67 value of ≥15% was identified to be statistically significant in association with certain luminal subtypes. The rate of disease-free survival was higher in patients with luminal A subtype BC (P=0.036). Following the correlation analysis for the Ki-67 index and the other prognostic factors, a Ki-67 value of ≥15% was revealed to be the optimal cut-off level for BC patients.
Annals of Surgery | 2013
Gül Alço; Maktav Dincer
W e have read with great enthusiasm the practice-changing article by Giuliano et al.1 In this trial, women with clinical T1 or T2N0M0 breast cancer treated with breastconserving surgery and sentinel lymph node dissection (SLND), who have 1 to 2 positive sentinel node(s), were randomized to completion axillary lymph node dissection (ALND) or no ALND and no further axillary-specific therapy, specifically no third field nodal irradiation. However, all patients received opposing tangential field whole breast irradiation. Adjuvant systemic chemotherapy and/or hormonal therapy were determined by consulting a physician and patient selection. At a median follow-up time of 6.3 years, regional recurrence (defined as recurrence in the axillary, supraclavicular, or internal mammary nodes) was seen in 0.5% of patients randomized to ALND compared with 0.9% of patients randomized to SLND alone. Their findings showed that “27% of patients in the ALND arm [of Z0011] had additional nodal metastases identified on histopathological assessment of the axillary contents,” meaning that “patients randomized to the SLND alone arm [of Z0011] were likely to have residual non-SLN metastasis that was not removed by operation”1 or intentional irradiation. However, the regional recurrence rates
Breast Journal | 2003
Vahit Ozmen; Neslihan Cabioglu; Abdullah Igci; Temel Dagoglu; Adnan Aydiner; Mustafa Kecer; Yavuz Bozfakioglu; Maktav Dincer; Ayhan Bilir; Erkan Topuz
Abstract: Twenty‐three patients with inflammatory breast cancer treated with a combined modality approach including anthracycline‐based induction chemotherapy‐surgery‐chemotherapy‐radiotherapy were reviewed. Twelve patients (52.2%) received FAC (5‐fluorouracil, adriamycin, cyclophosphamide) and 11 patients (47.8%) were treated with FEC (5‐fluorouracil, epirubicin, cyclophosphamide) induction chemotherapy for three cycles every 3 weeks. Surgery was followed by the initial chemotherapy or second‐line chemotherapy for an additional six cycles to complete nine cycles and radiotherapy, respectively. The median overall survival (OS) time was 27 months and the median disease‐free survival (DFS) was 13 months. Furthermore, patients treated with FAC induction chemotherapy have been found to have longer median OS and DFS periods compared to patients with FEC induction chemotherapy in both univariate and multivariate analysis. In conclusion, the superiority of doxorubicin‐containing chemotherapy over epirubicin‐containing chemotherapy should be established in larger randomized studies and more effective chemotherapeutic agents such as taxans are required for better survival rates in inflammatory breast cancer patients.