Araştırma Çıktıları | WoS | Scopus | TR-Dizin | PubMed
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Publication Metadata only Letter to the Editor: Radiotherapy Increases aMMP-8 Levels and Neutrophil/Lymphocyte Ratio Rapidly in Head and Neck Cancer Patients: A Pilot Study(SAGE Publications Ltd, 2023) Yilmaz, Busra; Topkan, Erkan; Pehlivan, Berrin; Selek, Uǧur; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Bahçeşehir Üniversitesi, Istanbul, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, Turkey[No abstract available]Publication Metadata only Review of Osteoradionecrosis of the Jaw: Radiotherapy Modality, Technique, and Dose as Risk Factors(Multidisciplinary Digital Publishing Institute (MDPI), 2023) Topkan, Erkan; Kucuk, Ahmet; Somay, Efsun; Yilmaz, Busra; Pehlivan, Berrin; Selek, Uǧur; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Kucuk, Ahmet, Clinic of Radiation Oncology, Mersin City Education and Research Hospital, Mersin, Turkey; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, Turkey, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, United StatesRadiotherapy (RT) or concurrent chemoradiotherapy (CCRT) is the cornerstone of organ-sparing or adjuvant therapy for nearly all head and neck cancers. Unfortunately, aggressive RT or CCRT can result in severe late toxicities, such as osteoradionecrosis of the jaws (ORNJ). The incidence of ORNJ is currently less than 5–6% due to advances in dental preventive care programs, RT planning systems, and RT techniques. Although numerous patient-, tumor-, and treatment-related factors may influence the incidence rates of ORNJ, RT modality (equipment), technique, and dose-volume-related factors are three of the most influential factors. This is mainly because different RT equipment and techniques have different levels of success at delivering the prescribed dose to the focal volume of the treatment while keeping the organ at risk safe. ORNJ risk is ultimately determined by mandibular dose, despite the RT technique and method being known predictors. Regardless of the photon delivery method, the radiobiological effects will be identical if the total dose, dose per fraction, and dose distribution within the tissue remain constant. Therefore, contemporary RT procedures mitigate this risk by reducing mandibular dosages rather than altering the ionizing radiation behavior in irradiated tissues. In light of the paucity of studies that have examined the impact of RT modality, technique, and dose-volume-related parameters, as well as their radiobiological bases, the present review aims to provide a comprehensive overview of the published literature on these specific issues to establish a common language among related disciplines and provide a more reliable comparison of research results. © 2023 Elsevier B.V., All rights reserved.Publication Metadata only Pre-chemoradiotherapy low hemoglobin levels indicate increased osteoradionecrosis risk in locally advanced nasopharyngeal cancer patients(Springer Science and Business Media Deutschland GmbH, 2023) Yilmaz, Busra; Somay, Efsun; Topkan, Erkan; Pehlivan, Berrin; Selek, Uǧur; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, Turkey, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, United StatesPurpose: We aimed to determine whether pretreatment hemoglobin (Hb) levels can predict the risk of osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal carcinoma (LA-NPC). Methods: ORN cases were identified from the records of LA-NPCs who had oral exams before and after CCRT. All Hb measurements were obtained on the first day of treatment. Receiving operating characteristic curve analysis was used to determine the relationship between Hb levels and ORN rates. The relationship between pretreatment Hb levels and ORN rates served as the primary endpoint, and secondary endpoints included the discovery of additional potential ORN risk factors. Results: Among the 263 eligible LA-NPCs, we identified 8.7% ORN cases. The ideal cutoff Hb before CCRT was 10.6 g/dL. It was revealed that HPR ≤ 10.6 group had a significantly higher ORN rate (32.5% vs. 1.5% for Hb > 10.6, P < 0.001). The mandibular V59.8 ≥ 36% Gy, pre-CCRT ≥ 4 tooth extractions, the presence of post-CCRT tooth extractions, and the time of post-CCRT tooth extractions > 8 months were the other factors associated with significantly increased ORN rates (P < 0.05 for each). Conclusion: Low pre-CCRT Hb levels appeared to be independently linked to significantly higher ORN rates. Pretreatment Hb levels may be used to establish preventive measures and predict ORN. © 2023 Elsevier B.V., All rights reserved.Publication Metadata only Comment on: Planned dose of intensity modulated proton beam therapy versus volumetric modulated arch therapy to tooth-bearing regions(Elsevier Ltd, 2023) Yilmaz, Busra; Topkan, Erkan; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Bahçeşehir Üniversitesi, Istanbul, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey[No abstract available]Publication Metadata only The predictive usefulness of the novel combined hemoglobin-to-platelet ratio and maximum mouth opening index on prevalence of radiation induced trismus in patients with nasopharyngeal cancer(John Wiley and Sons Inc, 2023) Somay, Efsun; Yilmaz, Busra; Topkan, Erkan; Kucuk, Ahmet; Pehlivan, Berrin; Selek, Uǧur; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Kucuk, Ahmet, Department of Radiation Oncology, Mersin City Hospital, Mersin, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, Turkey, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, United StatesObjectives: To explore how well a unique combination of hemoglobin-to-platelet ratio (HPR) and pretreatment maximum mouth opening (MMO) predicts the prevalence of radiation-induced trismus (RIT). Patients and methods: HPR and MMO cutoff values (0.54 and 40.7 mm) divided patients into two groups. To develop the novel HPR-MMO index, four combinations of these factors were tested for predictive power: Group 1: HPR > 0.54 and MMO > 40.7 mm, Group 2: HPR ≤ 0.54 but MMO > 40.7 mm, Group 3: HPR > 0.54 but MMO ≤ 40.7 mm, Group 4: HPR ≤ 0.54 and MMO ≤ 40.7 mm. Results: Data of 198 patients with LA-NPC was analyzed retrospectively. RIT rates for Groups 1 to 4 were 10.2%, 15.2%, 25%, and 59.4%. Groups 2 and 3 were merged to generate HPR-MMO index because of statistically equivalent RIT rates: Low-risk: HPR > 0.54 and MMO > 40.7 mm, Intermediate-risk: HPR ≤ 0.54 but MMO > 40.7 mm or, HPR > 0.54 but MMO ≤ 40.7 mm, High-risk: HPR ≤ 0.54 and MMO ≤ 40.7 mm. It was revealed that the low-, high-, and intermediate-risk group's RIT rates, 10.2%, 59.4%, and 19.2%, respectively. Conclusion: The novel HPR-MMO index may to classify LA-NPC patients into low, intermediate, and high-risk RIT groups. © 2023 Elsevier B.V., All rights reserved.Publication Metadata only Hemoglobin-to-platelet ratio in predicting the incidence of trismus after concurrent chemoradiotherapy(John Wiley and Sons Inc, 2023) Somay, Efsun; Yilmaz, Busra; Topkan, Erkan; Kucuk, Ahmet; Haksöyler, Veysel; Pehlivan, Berrin; Selek, Uǧur; Araz, Kenan; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Yilmaz, Busra, Department of Dentomaxillofacial Radiology, Başkent Üniversitesi, Ankara, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Kucuk, Ahmet, Department of Radiation Oncology, Mersin City Hospital, Mersin, Turkey; Haksöyler, Veysel, Department of Medical Oncology, Medline Hospital, Adana, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, Turkey, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, United States; Araz, Kenan, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, TurkeyObjective: The significance of pre-hemoglobin-to-platelet ratio (HPR) in predicting the occurrence of radiation-induced trismus (RIT) in locally advanced nasopharyngeal carcinoma patients (LA-NPC) who received concurrent chemoradiotherapy (C-CRT). Methods: The records of LA-NPC patients with oral examination before and after C-CRT were analyzed. Maximum mouth openings (MMO) were measured before and after C-CRT to confirm RIT status, with an MMO of ≤35 mm defined as RIT. HPR values were calculated on the first day of C-CRT. The relationship between the HPR values and RIT status was discovered using the receiver operating characteristic curve analysis. Results: A total of 43 patients RIT cases among 198 individuals were diagnosed. The optimal HPR cutoff that stratified the patients into two groups was 0.54. RIT incidence was found to be significantly higher in the HPR ≤0.54 group than its HPR >0.54 counterpart(p < 0.001). Univariately T3-4 stage, mean masticator apparatus dose>57.2Gy, and pre-C-CRT MMO ≤40.7 mm were found as the other significant correlates of increased RIT rates(p < 0.05). All four variables seemed to be independently connected to greater RIT incidence in multivariate analysis (p < 0.05, for each). Conclusion: The risk of post-C-CRT RIT may be significantly increased when pre-treatment HPR levels are low. © 2023 Elsevier B.V., All rights reserved.Publication Metadata only Initial neutrophil-to-lymphocyte ratio predicts radiation-induced trismus in parotid gland cancer(John Wiley and Sons Inc, 2023) Somay, Efsun; Yilmaz, Busra; Topkan, Erkan; Kucuk, Ahmet; Pehlivan, Berrin; Selek, Uǧur; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Kucuk, Ahmet, Department of Radiation Oncology, Mersin City Hospital, Mersin, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, Turkey, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, United StatesObjective: To investigate the link between pretreatment neutrophil-to-lymphocyte ratio(NLR) and the incidence of radiation-induced trismus(RIT) in parotid gland cancers(PGC) patients after postoperative radiotherapy(PORT). Method: Data of PGC patients who had oral examinations before and after PORT were reviewed retrospectively. We comprised patients who had maximum mouth opening (MMO) assessments before and after PORT and complete blood count test on the first day of PORT. MMO of ≤35 mm was considered as RIT. The receiver operating characteristic (ROC) curve analysis was used to search for an ideal NLR threshold value that might be linked to RIT rates. Results: Fifty-one patients were included, with a RIT incidence of 15.7%. The NLR cutoff that showed a link with the prevalence of RIT in the ROC curve analysis was 2.7[Area under the curve (AUC):82.0%, sensitivity:87.5%, specificity:74.4%]. The patients were divided into groups based on this value:Group 1: NLR≤2.7 (N = 34) and,NLR >2.7 (N = 17). In comparative analysis, the incidence of RIT was found to be statistically higher in the NLR >2.7 than counterpart (35.2%vs.5.8%,rs:0.79, p <.001). Also, a mean temporomandibular joint dose ≥51.0Gy was linked to increased RIT rates (p <.001). Conclusion: This study showed that high pre-PORT NLR levels were a robust and independent predictor of significantly elevated rates of RIT. © 2023 Elsevier B.V., All rights reserved.Publication Metadata only Utility of pre-chemoradiotherapy Pan-Immune-Inflammation-Value for predicting the osteoradionecrosis rates in locally advanced nasopharyngeal cancers(Springer Science and Business Media Deutschland GmbH, 2023) Yilmaz, Busra; Somay, Efsun; Topkan, Erkan; Kucuk, Ahmet; Pehlivan, Berrin; Selek, Uǧur; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Bahçeşehir Üniversitesi, Istanbul, Turkey; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Kucuk, Ahmet, Department of Radiation Oncology, Mersin City Hospital, Mersin, Turkey; Pehlivan, Berrin, Department of Radiation Oncology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Selek, Uǧur, Department of Radiation Oncology, Koç Üniversitesi, Istanbul, TurkeyPurpose: The aim of this retrospective study was to explore whether pretreatment Pan-Immune-Inflammation-Value (PIV) measurements might predict the risk of mandibular osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal cancer (LA-NPC). Methods: The platelet, monocyte, neutrophil, and lymphocyte counts acquired on the first day of CCRT were used to compute pretreatment PIV levels: PIV = (Platelets × Monocytes × Neutrophils) ÷ Lymphocytes. Receiver operating characteristic curve analysis was used to determine the association between ORN rates and PIV levels. Spearman correlation analysis was used to examine the probable intergroup correlations. The potential link between the pretreatment PIV levels and the post-treatment ORN rates was determined as the primary objective. Results: 21 (10.0%) of 210 eligible patients were diagnosed with ORN. The optimal pre-CCRT PIV cutoff was 833, which separated patients into two PIV groups with divergent ORN prevalence estimates: Group 1: PIV < 833 (N = 153), and Group 2: PIV ≥ 833 (N = 57). The comparison analysis found that the PIV ≥ 833 cohort had significantly higher ORN rates than the PIV < 833 cohort (29.8% vs. 2.6%, P < 0.001). Other characteristics linked to significantly higher ORN rates were the patient’s continuing smoking, the use of the Three-dimensional conformal radiation therapy technique, the mean mandibular dose of ≥ 58.1 Gy, the number of tooth extractions before CCRT ≥ 4, and the presence of tooth extractions after CCRT. The independent importance of all factors on higher ORN occurrence rates were retained in multivariate analysis (P < 0.05). Conclusions: Our findings revealed a strong link between aggravated inflammatory response and ORN genesis, with high pretreatment PIV levels related to significantly higher ORN rates. © 2023 Elsevier B.V., All rights reserved.Publication Metadata only Letter to the Editor regarding Radiologic findings of osteonecrosis, osteoradionecrosis, osteomyelitis and jaw metastatic disease with cone beam CT(Elsevier Ireland Ltd, 2023) Yilmaz, Busra; Topkan, Erkan; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Bahçeşehir Üniversitesi, Istanbul, Turkey; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey[No abstract available]Publication Metadata only Radiation therapy for cT1-2 carcinoma of the palatine tonsil diagnosed via a simple tonsillectomy: Dosimetry and patterns of care in the IMRT era(Elsevier Ltd, 2023) Topkan, Erkan; Somay, Efsun; Yilmaz, Busra; Topkan, Erkan, Department of Radiation Oncology, Başkent Üniversitesi, Ankara, Turkey; Somay, Efsun, Department of Oral and Maxillofacial Surgery, Başkent Üniversitesi, Ankara, Turkey; Yilmaz, Busra, Department of Oral and Maxillofacial Surgery, Bahçeşehir Üniversitesi, Istanbul, Turkey[No abstract available]
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