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Dive into the research topics where Melis Gultekin is active.

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Featured researches published by Melis Gultekin.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2012

High daily fraction dose external radiotherapy for T1 glottic carcinoma: treatment results and prognostic factors.

Melis Gultekin; Enis Özyar; Mustafa Cengiz; Gokhan Ozyigit; Mutlu Hayran; Sefik Hosal; Fadil Akyol

The purpose of this study was to investigate the prognostic factors and treatment results of T1N0M0 glottic laryngeal carcinoma irradiated with 2.3 Gray (Gy) per fraction.


International Journal of Biological Markers | 2007

Use of plasma Epstein-Barr virus DNA monitoring as a tumor marker in follow-up of patients with nasopharyngeal carcinoma: preliminary results and report of two cases

Enis Özyar; Melis Gultekin; A. Alp; G. Hasçelik; O. Ugur; I.L. Atahan

Recent studies suggest that plasma Epstein-Barr virus (EBV) DNA may reflect tumor burden in patients with nasopharyngeal cancer. A prospective study was initiated to investigate this correlation in 125 patients (34 pretreatment [Group A], 78 in remission [Group B] and 13 relapsed [Group C]) and 19 healthy controls. In group A, EBV DNA was detected in plasma samples of 24 (70%) patients. In Group B, EBV DNA was detected in 7 patients (range 77-13,731 copies/mL) and further imaging in all but one of these patients revealed active disease confirmed by ultrasound-guided fine-needle biopsy. There was only one false-positive case; this patient is currently under follow-up. Here we describe 2 of the 7 patients with detectable plasma EBV DNA in whom recurrence was documented by PET scan during follow-up. Our results showed that in group B the positive predictive value of quantitative analysis of plasma EBV DNA was 85%. Quantitative analysis of EBV DNA in plasma seems to become an integral part of screening, staging, monitoring, and prediction of relapse in patients with nasopharyngeal carcinoma. However, previous studies cannot be considered definitive and more reports on the use of this technique are urgently needed from both endemic and non-endemic regions.


International Journal of Gynecological Cancer | 2015

Assessing the Quality of Life in Patients With Endometrial Cancer Treated With Adjuvant Radiotherapy.

Havva Karabuga; Melis Gultekin; Gökhan Tulunay; Kunter Yuce; Ali Ayhan; Deniz Yuce; Ferah Yildiz

Objective The current study evaluates long-term quality of life (QOL) and sexual function of patients with endometrial cancer who received adjuvant pelvic external beam radiotherapy (EBRT) and/or vaginal brachytherapy (BRT). Materials and Methods One hundred forty-four endometrial cancer survivors who were treated between January 2000 and December 2009 in our department were included in this study. Median follow-up was 79 months (range, 31–138 months). Fifty-two patients were treated with 45 to 50.4 Gy EBRT, 76 were with BRT, and 16 were with both EBRT and BRT. Brachytherapy was in the form of vaginal cuff BRT with 5 × 550 cGy high dose rate BRT, prescribed to the first 4 cm and whole wall thickness of vagina. Quality of life was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and subscales from the supplemental 24-item Cervical Cancer Module. Results Vaginal BRT patients reported better physical functioning (P = 0.01), role functioning (P = 0.03), and sexual enjoyment (P = 0.01) compared to EBRT group. Symptom score (P = 0.01), lymphedema (P = 0.03), pain (P = 0.02), and diarrhea (P = 0.009) scores were also higher with EBRT. Vaginal BRT did not worsen symptom scores or sexual functions when added to EBRT. Obese patients experienced higher rates of lymphedema (P = 0.008). Cognitive and role functioning scores were significantly higher in patients with normal body mass index. Conclusions External beam radiotherapy negatively affects long-term QOL and sexual functions in endometrial cancer survivors. Vaginal BRT provides higher QOL. Patients with body mass index within normal limits have improved QOL.


Asian Pacific Journal of Cancer Prevention | 2014

Metaplastic Breast Carcinoma: a Heterogeneous Disease

Melis Gultekin; Gulnihan Eren; Taner Babacan; Ferah Yildiz; Kadri Altundag; Nilüfer Güler; Yavuz Ozisik; Gozde Yazici; Pervin Hurmuz; Murat Gurkaynak

The aim of this study is to evaluate clinicopathologic characteristics and the multi-disciplinary treatment results of metaplastic breast cancer (MBC) patients treated in a single institute. Seventeen female patients with MBC treated in our department between June 2000 and January 2012 were identified and retrospectively evaluated. The median age at diagnosis was 46 years (range, 26-66 years). The median tumor size at diagnosis was 3.5 cm (range 1.5-12 cm). Six (35%) patients underwent breast conservation surgery and 11 (65%) mastectomy. Axillary lymph node metastasis was found in 6 (35%) patients. Twelve (71%) had triple negative tumors. Postoperative RT and systemic adjuvant treatment was given to all patients accordingly to stage and biological characteristics. Median follow-up time was 27 months (range, 12-151 months). At the time of this analysis, 14 (82%) patients were alive with no evidence of disease, and 1 (6%) was alive with disease. The 3-year OS was 91% and 5-year 80%, and DFS rates were 76% and 76%, respectively. Despite the young age of our patients with mostly high grade tumors, larger tumor size and higher rates of lymph node metastasis, the survival outcomes in our study are favorable in comparison with previously reported series.


The Breast | 2014

Impact of locoregional treatment on survival in patients presented with metastatic breast carcinoma

Melis Gultekin; Ozan Yazici; Gulnihan Eren; Deniz Yuce; Sercan Aksoy; Yavuz Ozisik; Nilüfer Güler; Gozde Yazici; Pervin Hurmuz; Ferah Yildiz; Kadri Altundag; Murat Gurkaynak

OBJECTIVES In this study, we tried to evaluate the efficacy of locoregional treatment (LRT) in patients with metastatic breast carcinoma (MBC). MATERIALS AND METHODS The medical records of 227 patients with MBC at initial presentation between April 1999 and January 2013 were retrospectively evaluated. The median age at diagnosis was 50 years (range, 27-83 years). Thirty-nine patients (17%) had no LRT. Among patients who had LRT, 2 (1%) had locoregional radiotherapy (RT) alone, 54 (29%) had surgery alone [mastectomy, n = 50; breast conserving surgery (BCS), n = 4] and 132 (70%) had surgery (mastectomy, n = 119; BCS, n = 13) followed by locoregional RT. RESULTS The median follow-up time was 35 months (range, 4-149 months). Five-year OS and PFS rates were 44% and 20%, respectively. In both univariate and multivariate analysis LRT per se did not affect OS and PFS rates. However, the 5-year OS and PFS rates were significantly higher in patients treated with locoregional RT than the ones who were not. The corresponding rates were 56% vs. 24% for OS and 27% vs. 7% for PFS (p < 0.001). Median survival was 67 months and 37 months, respectively. CONCLUSION Our study showed that patients with MBC who received postoperative locoregional RT may have a survival advantage compared with patients who were only treated by surgery. A phase III trial testing the role of adjuvant locoregional RT may help to distinguish patients who will benefit from adjuvant RT.


Technology in Cancer Research & Treatment | 2014

Fractionated Stereotactic Radiosurgery Treatment Results for Skull Base Chordomas

Faruk Zorlu; Melis Gultekin; Mustafa Cengiz; Ferah Yildiz; Fadil Akyol; Murat Gurkaynak; Gokhan Ozyigit

Chordomas are uncommon neoplasms and there is still controversy regarding establishment of diagnosis and management. The aim of this study was to evaluate efficacy and toxicity of fractionated stereotactic radiosurgery (FSRS) in skull base chordomas. There were 4 female (36%) and 7 male (64%) patients. FSRS was delivered with CyberKnife (Accuray Inc., Sunnyvale, CA). The median tumor volume was 14.7 cc (range, 3.9–40.5 cc). The median marginal tumor dose was 30 Gy (range, 20–36 Gy) in a median 5 fractions (range, 3–5 fractions). The median follow-up time was 42 months (range, 17–63 months). At the time of analysis, 10 (91%) patients were alive and 1 (9%) had died due to tumor progression. Of 10 patients, 8 (73%) had stable disease and the remaining 2 (18%) had progressive disease. The actuarial overall survival (OS) after FSRS was 91% at two-years. Two patients developed radiation-induced brain necrosis as a complication in the 8th and 28th months of follow-up, respectively. Our results with robotic FSRS in skull base chordomas are promising for selected patients. However, due to the slow growth pattern of skull base chordomas, a longer follow-up is required to determine exact treatment results and late morbidity.


World journal of clinical oncology | 2014

Current role of modern radiotherapy techniques in the management of breast cancer.

Gokhan Ozyigit; Melis Gultekin

Breast cancer is the most common type of malignancy in females. Advances in systemic therapies and radiotherapy (RT) provided long survival rates in breast cancer patients. RT has a major role in the management of breast cancer. During the past 15 years several developments took place in the field of imaging and irradiation techniques, intensity modulated RT, hypofractionation and partial-breast irradiation. Currently, improvements in the RT technology allow us a subsequent decrease in the treatment-related complications such as fibrosis and long-term cardiac toxicity while improving the loco-regional control rates and cosmetic results. Thus, it is crucial that modern radiotherapy techniques should be carried out with maximum care and efficiency. Several randomized trials provided evidence for the feasibility of modern radiotherapy techniques in the management of breast cancer. However, the role of modern radiotherapy techniques in the management of breast cancer will continue to be defined by the mature results of randomized trials. Current review will provide an up-to-date evidence based data on the role of modern radiotherapy techniques in the management of breast cancer.


Physica Medica | 2015

Determination of optimal planning target volume margins in patients with gynecological cancer

Ceyran Yilmaz; Melis Gultekin; Gulnihan Eren; Deniz Yuce; Ferah Yildiz

PURPOSE To define optimal planning target volume (PTV) margins for intensity modulated radiotherapy (IMRT) ± knee-heel support (KHS) in patients treated with adjuvant radiotherapy. METHODS Computed tomography (CT) scans ± KHS of 10 patients were taken before and at 3rd and 5th week of treatment, fused and compared with initial IMRT plans. RESULTS A PTV margin of 15 mm in anteroposterior (AP) and superoinferior (SI) directions and 5 mm in lateral directions were found to be adequate without any difference between ± KHS except for the SI shifts in CTV-primary at the 3rd week. Five mm margin for iliac CTV was found to be inadequate in 10-20% of patients in SI directions however when 7 mm margin was given for iliac PTV, it was found to be adequate. For presacral CTV, it was found that the most striking shift of the target volume was in the direction of AP. KHS caused significantly less volume of rectum and bladder in the treated volume. CONCLUSIONS PTV margin of 15 mm in SI and AP, and 5 mm in lateral directions for CTV-primary were found to be adequate. A minimum of 7 mm PTV margin should be given to iliac CTV. The remarkable shifting in presacral CTV was believed to be due to the unforeseen hip malposition of obese patients. The KHS seems not to provide additional beneficial effect in decreasing the shifts both in CTV-primary and lymphatic, however it may have a beneficial effect of decreasing the OAR volume in PTV margins.


Technology in Cancer Research & Treatment | 2013

Robotic Stereotactic Radiosurgery in Patients with Nasal Cavity and Paranasal Sinus Tumors

Gokhan Ozyigit; Mustafa Cengiz; Pervin Hurmuz; Gozde Yazici; Melis Gultekin; Fadil Akyol; Ferah Yildiz; Murat Gurkaynak; Faruk Zorlu

The aim of this retrospective study is to evaluate our therapeutic results in patients with paranasal sinus (PNS) or nasal cavity (NC) malignancies treated with robotic stereotactic radiosurgery (SRS). Between August 2007 and October 2008, 27 patients with PNS or NC tumors were treated in our department using SRS. Median age was 53 years (range, 27–84 years). Eleven patients were female and sixteen were male. Most common histopathology was SCC (44%). The disease involved the maxillary sinus in 15 patients (55%). SRS was applied to 6 patients (22%) for reirradiation, while the others received it as a primary treatment. Seven patients had SRS as a boost dose to external beam radiotherapy. SRS was delivered with cyberknife (Accuray Incorporated, Sunnyvale, CA, USA). The median dose to the tumor was 31 Gy (range, 15–37.5 Gy) in median 5 fractions (range, 3–5 fractions). After a median follow-up of 21.4 months (range, 3–59 months), 76% of the patients were free of local relapse. Three patients showed local progression and 3 developed distant metastases. One- and two-year survival rates for the entire group were 95.2% (SEM = 0.046) and 77.1% (SEM = 0.102), respectively. We observed brain necrosis in 2 patients, visual disorder in 2 patients, bone necrosis in 2 patients and trismus in 1 patient as a SRS related late toxicity. Robotic SRS seems to be a feasible treatment strategy for patients with PNS tumors. Further prospective studies with longer follow up times should be performed.


Technology in Cancer Research & Treatment | 2017

Reirradiation of Pediatric Tumors Using Hypofractionated Stereotactic Radiotherapy

Melis Gultekin; Mustafa Cengiz; Duygu Sezen; Faruk Zorlu; Ferah Yildiz; Gozde Yazici; Pervin Hurmuz; Gokhan Ozyigit; Fadil Akyol; Murat Gurkaynak

Background: This study aimed to evaluate the efficacy and safety of hypofractionated stereotactic radiotherapy for reirradiation of recurrent pediatric tumors. Methods and Materials: The study included 23 pediatric patients who were reirradiated using hypofractionated stereotactic radiotherapy in the radiation oncology department between January 2008 and November 2013. In total, 33 tumors were treated—27 (82%) cranial and 6 (18%) extracranial. Hypofractionated stereotactic radiotherapy was administered due to recurrent disease in 31 (94%) tumors and residual disease in 2 (6%) tumors. The median total dose was 25 Gy (range: 15-40 Gy), and the median follow-up was 20 months (range: 2-68 months). Results: The 1-year and 2-year local control rates in the entire study population were 42% and 31%, respectively. The median local control time was 11 months (range: 0-54 months) following hypofractionated stereotactic radiotherapy. The patients with tumor response after hypofractionated stereotactic radiotherapy had significantly longer local control than the patients with post-hypofractionated stereotactic radiotherapy tumor progression (21 vs 3 months, P < .001). Tumor volume <1.58 cm3 was correlated (not significantly) with better local control (23 vs 7 months, P = .064). Conclusion: Reirradiation of pediatric tumors using hypofractionated stereotactic radiotherapy is a safe and effective therapeutic approach. This treatment modality should be considered as a treatment option in selected pediatric patients.

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