Browsing by Author "Tezcanli, Evrim"

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Concurrent Use of Cyclin Dependent Kinase 4/6 (CDK4/6) Inhibitors with Palliative Radiotherapy for Metastatic Breast Cancer Patients: A Review of Toxicity
(KARE PUBL, 2021-01-01) Sonmez, Ozlem; Tezcanli, Evrim
Breast cancer remains to be the most common cancer in women. Given the recent developments in oncology, while more women with early breast cancer are being cured, patients with metastatic breast cancer are living longer. There have been improvements in the treatment of hormone-sensitive metastatic breast cancer by the addition of CDK 4/6 inhibitors to endocrine treatment. CDK 4 and CDK 6 control entry into the cell cycle via estrogen signaling pathway and their inhibition was shown to prevent tumor cell cycle progression. Three CDK4/6 inhibitors available for hormone receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer are palbociclib, ribociclib, and abemaciclib. CDK 4/6 inhibitors are suggested as radiosensitizers given their mechanism of action that inhibits cell cycle progression as well as DNA repair. However, there are concerns regarding their concurrent use with radiotherapy given their potential to delay normal tissue repair. Currently, there are several retrospective series suggesting a site-dependent toxicity. After reviewing preclinical and retrospective studies, we suggest further studies are required to clarify the safety of this combination. Until then, oncologists should evaluate each case with caution regarding the potential risks of CDK 4/6 inhibitors in combination with radiotherapy.
Coronaphobia: A barrier to ongoing cancer treatment?
(WILEY, 2022-01-01) Sonmez, Ozlem; Tezcanli, Evrim; Tasci, Elif Senocak; Kazanci, Hande Busra; Altinok, Ayse; Toklucu, Elvan; Tasci, Yusuf; Aydogdu, Cise; Aydin, Aysegul Bakir; Yuce, Sabiha; Oyan, Basak
Introduction Increased stress levels caused by the pandemic might cause delays in cancer treatment. We conducted a survey among cancer patients undergoing treatment to evaluate their psychological wellbeing and treatment adherence during Coronavirus disease 19 (COVID-19) pandemic. Material and Methods Patients receiving active chemotherapy at a private oncology center between January and May 2021 were included. Healthy volunteers were employees of a district health directorate with no history of cancer or chronic disease. Treatment adherence was described as compliant if the prescribed treatment was received within a week and the information was gained from patient charts. Hospital anxiety and depression scale (HADS) and COVID-19 phobia scale (CP19-S) were administered to participants. Results 402 participants were included
Dosimetric evaluation of VMAT and helical tomotherapy techniques comparing conventional volumes with clinical target volumes based on new ESTRO ACROP post-mastectomy with immediate implant reconstruction contouring guidelines
(BMC, 2022-01-01) Goksel, Evren Ozan; Tezcanli, Evrim; Arifoglu, Alptekin; Kucucuk, Halil; Senkesen, Oznur; Abacioglu, Ufuk; Aslay, Isik; Sengoz, Meric
Background The ESTRO-ACROP Consensus Guideline (EACG) recommends implant excluded clinical target volume (CTVp) definitions for post-mastectomy radiation therapy after implant-based immediate breast reconstruction (IBR). The purpose of this study is to investigate the effectiveness of Helical Tomotherapy (HTp) and Volumetric Modulated Arc Therapy (VMATp) treatment techniques in terms of CTVp coverage and reduced organ at risk (OAR), normal tissue and implant doses when CTVp was used for treatment planning as the target structure instead of conventional CTV. Methods Eight left-sided and eight right-sided breast cancer patients who underwent IBR after mastectomy were included in this study. Planning CT data sets were acquired during free breathing and patients were treated with HT technique targeted to conventional CTV. Retrospectively, CTVp was delineated based on EACG by the same radiation oncologist, and treatment plans with HTp and VMATp techniques were generated based on CTVp. For each patient, relevant dosimetric parameters were obtained from three different treatment plans. Results There was no statistically significant difference on target coverage in terms of, PTVp-D95, PTVp-Vpres, homogeneity index (p > 0.05) between HTp and VMATp plans. But, the conformity numbers were significantly higher (HTp vs VMATp, 0.69 +/- 0.15 vs 0.79 +/- 0.12) for VMATp (Z = - 2.17, p = 0.030). While HTp significantly lowered Dmax and Dmean for LAD (LAD-D-max: chi(2) = 12.25, p = 0.002 and LAD-D-mean: chi(2) = 12.30, p = 0.002), neither HTp nor VMATp could reduce maximum and mean dose to heart (p > 0.05). Furthermore, heart volume receiving 5 Gy was significantly higher for VMATp when compared to HTp (21.2 +/- 9.8 vs 42.7 +/- 24.8, p: 0.004). Both techniques succeeded in reducing the mean dose to implant (HTp vs HT, p < 0.001
Gamma Knife Radiosurgery for Arteriovenous Malformations: Clinical Series of 199 Patients
(TURKISH NEUROSURGICAL SOC, 2017-01-01) Arslan, Ipek; Tezcanli, Evrim; Yilmaz, Meltem; Cizmeli, Olcay; Sengoz, Meric; Peker, Selcuk
AIM: Cerebral arteriovenous malformations (AVM) are pathological connections between arteries and veins without capillaries. Stereotactic radiosurgery (RS) is a proven and accepted treatment method for cerebral AVMs. Our objective was to analyze the factors influencing the clinical outcome in patients suffering from AVMs. MATERIAL and METHODS: We retrospectively reviewed 199 patients who were treated with Gamma-Knife RS for intracranial AVMs between 13 October 2005 and 31 October 2010. There were 89 male, 110 female patients with a median age of 32 years (range, 3-74 years). Obliteration was assessed with MRI angiography and DSA imaging. RESULTS: Complete obliteration rate after RS was 71 \% (141 out of 199), including second RS treatments. In terms of obliteration rates, there was no significant difference between patients younger and older than 21 years old (p=0.669). After RS, 3 patients died due to intracranial hemorrhage and 1 died of heart disease. Death from AVM was determined as 1.5 \%. Intracranial hemorrhage was observed in 7 (3.5 \%) patients post-RS. CONCLUSION: Obliteration was found to be associated with Spetzler-Martin Grade, Pollock-Flickinger Grade, AVM volume, RS dose, bleeding history before RS and no previous embolization before RS. Gamma knife RS is an effective treatment method for the treatment of AVMs both for pediatric and adult patients. It provides high obliteration and low mortality rates.
GAMMA KNIFE RADIOSURGERY FOR RECURRENT HIGH GRADE GLIOMAS
(OXFORD UNIV PRESS INC, 2014-01-01) Peker, Selcuk; Kabalay, Ipek Arslan; Tezcanli, Evrim; Yilmaz, Meltem; Sengoz, Meric
Limited field adaptive radiotherapy for glioblastoma: changes in target volume and organ at risk doses
(KOREAN SOC THERAPEUTIC RADIOLOGY \& ONCOLOGY, 2022-01-01) Senkesen, Oznur; Tezcanli, Evrim; Abacioglu, Mehmet Ufuk; Ozen, Zeynep; Cone, Derya; Kucucuk, Halil; Goksel, Evren Ozan; Arifoglu, Alptekin; Sengoz, Meric
Objective: This study aimed to investigate the tumor volume changes occurring during limited-field radiotherapy (RT) for glioblastoma patients and whether a volume-adapted boost planning approach provided any benefit on tumor coverage and normal tissue sparing. Materials and Methods: Twenty-four patients underwent simulation with magnetic resonance (MR) and computed tomography (CT) scans prior to RT (MR\_initial, CT\_initial) and boost treatment (MR\_adapt, CT\_adapt). For the boost phase, MR\_initial and MR\_adapt images were used to delineate GTV(2) and GTV(2\_adapt), respectively. An initial boost plan (Plan\_initial) created on CT\_initial for PTV2 was then reoptimized on CT\_adapt by keeping the same optimization and normalization values. Plan\_adapt was generated on CT\_adapt for PTV(2\_adapt )volume. Dose volume histogram parameters for target volumes and organs-at-risk were compared using these boost plans generated on CT\_adapt. Plan\_initial and Plan\_adaptive boost plans were summed with the first phase plan and the effect on the total dose was investigated. Results: Target volume expansion was noted in 21 0 /c, of patients while 791b had shrinkage. The average difference for the initial and adaptive gross tumor volume (G1V), clinical target volume (CTV), and planning target volume (PTV) volumes were statistically significant. Maximum dose differences for brainstem and optic chiasm were significant. Healthy brain tissue V-10 and ipsilateral optic nerve maximum doses were found to decrease significantly in Plan\_adaptive. Conclusion: Results of this study confirm occurrence of target volume changes during RT for glioblastoma patients. An adaptive plan can provide better normal tissue sparing for patients with lesion shrinkage and avoid undercoverage of treatment volumes in case of target volume expansion especially when limited-fields are used.
The Great Mimicker: Zona Zoster at the Mastectomy Site Causing Contralateral Intramammary Lymph Node Enlargement
(HINDAWI LTD, 2012-01-01) Ozcan, Umit Aksoy; Tezcanli, Evrim; Yildirim, Yesim; Garipagaoglu, Melahat
Zona zoster is rarely observed in patients with malignancy
Tumor-stage mycosis fungoides of the vulva successfully treated with local low-dose radiotherapy
(WILEY-BLACKWELL, 2015-01-01) Bakar, Ozgur; Sahin, Sedef; Cetinozman, Fatma; Willemze, Rein; Tezcanli, Evrim; Cetin, Emel Dikicioglu
Mycosis fungoides (MF) is the most common type of primary cutaneous T-cell lymphoma. According to the proposed guidelines for MF, skin-directed therapies are the treatment of choice for patients with limited stage disease. We present a case of early-stage MF, who progressed to tumor-stage MF during the postpartum period, showing a solitary ulcerated tumor on the vulva, which was successfully treated with local response-based, low-dose radiotherapy.