Publications by authors named "Melek Yavuz"
Background: This study evaluated the impact of radiotherapy (RT) with or without a simultaneous integrated boost (SIB) to intraprostatic lesions on survival, recurrence, and toxicity in localized prostate cancer (PCa). Key prognostic and predictive factors were also analyzed.
Materials And Methods: A retrospective analysis included 712 intermediate- and high-risk PCa patients treated with external beam RT at 78 Gy, with or without SIB (up to 86 Gy), between 2010 and 2018.
Purpose: This study aimed to investigate the effects of dose escalation through focal boost (FB) to intraprostatic lesions (IPLs) as well as the role of gallium-68 prostate-specific membrane antigen positron-emission tomography (Ga-PSMA-PET/CT) for staging and treatment planning in patients with Gleason score (GS) 10 prostate cancer (PCa) receiving definitive radiotherapy (RT) and androgen deprivation therapy (ADT).
Materials And Methods: We retrospectively analyzed data of 92 patients with GS 10 PCa who underwent definitive RT and ADT from March 2010 to October 2022. Freedom from biochemical failure (FFBF), prostate cancer-specific survival (PCSS), distant metastasis-free survival (DMFS), and overall survival (OS) rates were calculated using the Kaplan-Meier method.
Article Synopsis
- The study evaluated the outcomes of younger (< 70 years) and older (≥ 70 years) prostate cancer patients after receiving definitive radiotherapy, focusing on disease-free survival and side effects.
- Findings showed similar 7-year biochemical disease-free survival and prostate cancer-specific survival rates between the two age groups, despite older patients having additional risk factors and comorbidities.
- The research concluded that definitive radiotherapy is a safe and effective treatment for localized prostate cancer regardless of age, as older patients experience comparable rates of survival and toxicity to younger ones.
Purpose: To assess the early metabolic response of the primary tumor using Gallium-68 (Ga)-labeled-prostate-specific membrane antigen positron emission tomography (Ga-PSMA-PET/CT), as well as the relationship between PSMA change in the primary tumor and PSA response after definitive radiotherapy (RT), either alone or in combination with androgen deprivation therapy (ADT) in intermediate risk prostate cancer (IR-PCa) patients.
Methods: The clinical data of 71 IR-PCa patients treated with RT alone (36 patients, 50.7%) or RT and ADT (35 patients, 49.
Purpose: This study sought to determine the predictive and prognostic value of clinicopathological parameters and neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and hemoglobin (Hgb) level in predicting recurrence patterns and locoregional relapse-free survival (LRFS) and distant metastasis-free survival (DMFS) in cervical cancer patients receiving definitive chemoradiotherapy (ChRT).
Methods: This study included 261 cervical cancer patients treated with ChRT. The primary endpoints were the predictors of local recurrence (LR) and distant metastasis (DM), whereas the secondary endpoints were LRFS and DMFS.
Article Synopsis
- The study examined the effectiveness of PSMA PET/CT imaging compared to traditional imaging methods in treatment outcomes for patients with node-positive prostate cancer who received androgen deprivation therapy (ADT) and external radiotherapy (RT).
- Results showed that patients assessed with PSMA PET/CT had significantly higher 5-year prostate cancer-specific survival rates (95.1%) compared to those who underwent conventional imaging (76.9%).
- Findings suggested that factors such as the duration of ADT and post-RT PSA levels were crucial in predicting both progression-free survival and survival specific to prostate cancer, indicating that PSMA PET/CT provides better prognostic information for patient outcomes.
Aim: The aim of this study was to explore nursing students' views on the theory-practice gap in surgical nursing education and determine its relationship with attitudes towards the profession and evidence-based practice.
Background: In nursing education, the discrepancy between the theoretical knowledge and clinical practices is known as the "theory-practice gap". Although this problem was defined many years ago, scientific information on the subject is very limited in terms of surgical nursing.
Could Amifostine Prevent Experimental Radiotherapy-Induced Acute Pericarditis?
Asian Pac J Cancer Prev
September 2022
Background: Amifostine is a powerful antioxidant that is one of the documented three chemo-radio prototectants recommended for clinical use. There is no data exploring amifostine in prevention of acute pericardial damage. We aimed to investigate whether amifostine has protective effect against acute pericardial injury due to radiotherapy in an experimental rat model.
View Article and Find Full Text PDFAim: The study evaluates the different treatment planning techniques according to three recommendation levels of the International Commission on Radiation Units and Measurements Report-83 in gynecologic cancer patients treated with adjuvant pelvic radiotherapy (APR).
Materials And Methods: Computerized tomography images of ten endometrial and cervical cancer patients who were treated with APR were assessed. For each patient, five different treatment plans were created.
Objectives: To evaluate the long-term clinical efficacy and toxicity of concomitant boost radiotherapy (CBRT) in elderly patients with invasive bladder cancer.
Methods And Materials: Elderly patients (n=188; mean 75-year-old, range 70-91 years; 88.3% male/11.
Purpose: The aim of this study was to evaluate the long-term clinical efficacy and toxicity of concomitant boost and accelerated hyperfractionated radiation therapy (CBAHRT) in patients with invasive bladder cancer.
Methods And Materials: Between October 1997 and September 2012, 334 patients with diagnoses of invasive bladder cancer were selected. These patients received CBAHRT as a bladder-conserving approach.
Introduction: The aim of this study was to compare computed tomography (CT)- and positron emission tomography (PET)/CT-based gross tumor volume (GTV) delineation and its subsequent expansion to the planning target volume (PTV), and to analyze the resultant doses of 3-dimensional conformal radiotherapy (3D-CRT) to critical organs.
Methods: 15 patients with unresectable extrahepatic cholangiocarcinoma (EHCC) were enrolled into this study. PTVCT-based plans were initially made, and then PTVPET-CT-based plans were created using the same beam angles and isocenter.
Background: Radiotherapy (RT) for abdominal and pelvic malignancies often causes severe small bowel toxicity. Citrulline concentrations are known to decrease with intestinal failure. We thus evaluated the feasibility of plasma citrulline levels in predicting radiation-induced intestinal toxicity.
View Article and Find Full Text PDFPurpose: To compare the protective effects of the potent antioxidants, melatonin and octreotide, against radiation-induced intestinal injury.
Methods: A total of 42 male 3-month-old Swiss albino mice (40 ± 10 g) were matched according to body weight and randomly assigned to one of six groups: control; radiation treatment (RT) only; melatonin only (15 mg/kg, i.p.
Background: When combined with adequate tumoricidal doses, accurate target volume delineation remains to be the one of the most important predictive factors for radiotherapy (RT) success in locally advanced or medically inoperable malignant pleural mesothelioma (MPM) patients. Recently, 18-fluorodeoxyglucose positron emission tomography (PET) has demonstrated significant improvements in diagnosis and accurate staging of MPM. However, role of additional PET data has not been studied in RT planning (RTP) of patients with inoperable MPM or in those who refuse surgery.
View Article and Find Full Text PDFBackground: To compare intracavitary brachytherapy (ICBT) planning methods for cervical cancer, based on either orthogonal radiographs (conventional plan) or CT sections (CT plan); the comparison focused on target volume coverage and dose volume analysis of organs at risk (OARs), by representing point doses defined by the International Commission on Radiation Units and Measurement (ICRU) and dose volume histograms (DVHs) from 3D planning.
Methods: We analyzed the dosimetric data for 62 conventional and CT-based ICBT plans. The gross tumor volume (GTV), clinical target volume (CTV) and organs at risk (OAR)s were contoured on the CT-plan.
Background: To evaluate the impact of four different rectum contouring techniques and rectal toxicities in patients with treated with 3D conformal radiotherapy (3DCRT).
Methods: Clinical and dosimetric data were evaluated for 94 patients who received a total dose 3DCRT of 70 Gy, and rectal doses were compared in four different rectal contouring techniques: the prostate-containing CT sections (method 1); 1 cm above and below the planning target volume (PTV) (method 2); 110 mm starting from the anal verge (method 3); and from the anal verge to the sigmoid flexure (method 4). The percentage of rectal volume receiving RT doses (30-70 Gy) and minimum, mean rectal doses were assessed.
As a result of improved local and regional control with aggressive multimodality protocols, the brain has become one of the major sites of relapse in patients with locally advanced non-small cell lung carcinoma (LA-NSCLC). The demonstrated efficacy of prophylactic cranial irradiation (PCI) in small-cell lung carcinoma led to studies of its effectiveness in LA-NSCLC, which indicated that PCI also has a high potential to reduce the incidence or delay the occurrence of brain metastases in this patient group. This report provides an extensive review of the current evidence from nonrandomized and randomized trials regarding the use of PCI in LA-NSCLC and discusses related key issues including risk factors, patient selection criteria, timing of PCI, preferred PCI dosing scheme, toxicity profile and potential novel PCI techniques.
View Article and Find Full Text PDFBackground: Prophylactic cranial irradiation (PCI) has been demonstrated to reduce or delay the incidence of brain metastases (BM) in locally advanced non-small cell lung carcinoma (LA-NSCLC) patients with various prognostic groups. With this current cohort we planned to evaluate the potential usefulness of prophylactic cranial irradiation (PCI) specifically in recursive partitioning analysis (RPA) Group 1, which is the most favorable group of LA-NSCLC patients.
Methods: Between March 2007 and February 2008, 62 patients in RPA group 1 were treated with sequential chemoradiotherapy and PCI for stage IIIB NSCLC.
Purpose: We compared the effects of amifostine and melatonin in preventing radiation-induced epiphyseal growth plate injury in rats.
Materials And Methods: Four-week-old (65-85 g), growing male Sprague-Dawley rats were randomly assigned to receive radiation alone, at 25 Gy in three fractions (group R), or this dose of fractionated radiation proceeded by prophylactic amifostine 200 mg/kg i.p.
Background: To compare computed tomography (CT) with co-registered positron emission tomography-computed tomography (PET-CT) as the basis for delineating gross tumor volume (GTV) in unresectable, locally advanced pancreatic carcinoma (LAPC).
Methods: Fourteen patients with unresectable LAPC had both CT and PET images acquired. For each patient, two three-dimensional conformal plans were made using the CT and PET-CT fusion data sets.
Background: The purpose of this study was to evaluate the efficacy of oral glutamine in the prevention of acute radiation-induced esophagitis (ARIE) and weight loss in lung carcinoma patients, and to determine the clinical/dosimetric predictors of ARIE.
Patients And Methods: Data from 41 patients with stage III lung carcinoma treated with thoracic irradiation were retrospectively analyzed. Twenty-two patients (53.