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Author: search.filters.author.Topkan, Erkansearch.filters.applied.f.publicationcategory: search.filters.publicationcategory.Makale - Uluslararası Hakemli Dergi

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    Systemic Inflammation Score for Predicting Radiation-Induced Trismus and Osteoradionecrosis of the Jaw Rates in Locally Advanced Nasopharyngeal Carcinoma Patients
    (2023) Somay, Efsun; Sezen, Duygu; Selek, Ugur; Besen, Ali Ayberk; Mertsoylu, Huseyin; Topkan, Erkan; 0000-0001-8120-7123; AAG-2213-2021
    We sought to determine the predictive value of the systemic inflammation score (SIS) for radiation-induced trismus (RIT) and osteora-dionecrosis of the jaw (ORNJ) in locally advanced nasopharyngeal carcinoma (LA-NPC) patients treated with concurrent chemoradio-therapy (C-CRT). LA-NPC patients (n= 188) who underwent C-CRT and pre-and post-C-CRT oral examinations from August 2010 to January 2022 were included. The three-tiered SIS groups were created using the serum albumin and lymphocyte-to-monocyte ratio (LMR) measures obtained on the first day of C-CRT: SIS-0: Albumin >= 40 g/dL and LMR >= 4.44); SIS-1: Albumin < 40 g/dL and LMR < 4.44 or albumin >= 0 g/dL and LMR >= 4.44; and SIS-2: Albumin < 40 g/dL and LMR <4.44. The primary objective was to ascertain whether there were irrefutable associations between pretreatment SIS groups and the respective post-C-CRT RIT and ORNJ rates. RIT and ORNJ were diagnosed in 33 (17.6%) and 21 (11.1%) patients, respectively. There were 12 (32.4%), 13 (12.7%), and 18 (45.0%) cases diagnosed with RIT in the respective SIS-0, SIS-1, and SIS-2 groups (p< 0.001). Similarly, there were 1 (2.7%), 11 (9.9%), and 9 (22.5%) cases with ORNJ diagnoses in the corresponding SIS groups (p< 0.001). The multivariate analysis's findings revealed that the SIS grouping was an independent predictor of RIT (p< 0.001) and ORNJ incidence rates (p< 0.001). Our study's findings indicate that the novel pretreatment SIS grouping is a dependable biomarker-based system, which can accurately predict the rates of RIT and ORNJ in LA-NPC patients who receive definitive C-CRT.
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    Pretreatment Masseter Muscle Volume Predicts Survival in Locally Advanced Nasopharyngeal Carcinoma Patients Treated with Concurrent Chemoradiotherapy
    (2023) Pehlivan, Umur Anil; Somay, Efsun; Yilmaz, Busra; Besen, Ali Ayberk; Mertsoylu, Huseyin; Selek, Ugur; Topkan, Erkan; 0000-0001-5871-0695; 0000-0001-8251-6913; 0000-0001-8120-7123; 37959329; AAG-2213-2021
    Background and purpose: Muscle loss is a significant indicator of cancer cachexia and is associated with a poor prognosis in cancer patients. Given the absence of comparable studies, the current retrospective study sought to examine the correlation between the total masseter muscle volume (TMMV) before treatment and the survival outcomes in locally advanced nasopharyngeal cancer (LA-NPC) patients who received definitive concurrent chemoradiotherapy (CCRT). Methods: A three-dimensional segmentation model was used to determine the TMMV for each patient by analyzing pre-CCRT magnetic resonance imaging. The optimal TMMV cutoff values were searched using receiver operating characteristic (ROC) curve analyses. The primary and secondary endpoints were the relationship between the pre-CCRT TMMV measures and overall survival (OS) and progression-free survival (PFS), respectively. Results: Ninety-seven patients were included in this study. ROC curve analyses revealed 38.0 cc as the optimal TMMV cutoff: <= 38.00 cc (n = 42) and >38.0 cc (n = 55). Comparisons between the two groups showed that the TMMV>38.0 cc group had significantly longer PFS [Not reached (NR) vs. 28; p < 0.01] and OS (NR vs. 71; p < 0.01) times, respectively. The results of the multivariate analysis demonstrated that the T-stage, N-stage, number of concurrent chemotherapy cycles, and TMMV were independent associates of PFS (p < 0.05 for each) and OS (p < 0.05 for each) outcomes, respectively. Conclusion: The findings of the current retrospective research suggest that pretreatment TMMV is a promising indicator for predicting survival outcomes in LA-NPC patients receiving definitive CCRT.
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    Predicting Teeth Extraction after Concurrent Chemoradiotherapy in Locally Advanced Nasopharyngeal Cancer Patients Using the Novel GLUCAR Index
    (2023) Somay, Efsun; Topkan, Erkan; Yilmaz, Busra; Besen, Ali Ayberk; Mertsoylu, Huseyin; Selek, Ugur; 0000-0001-8120-7123; 0000-0001-8251-6913; 38066835; AAG-2213-2021
    To evaluate the value of the newly created GLUCAR index in predicting tooth extraction rates after concurrent chemoradiotherapy (C-CRT) in locally advanced nasopharyngeal carcinomas (LA-NPCs). Methods: A total of 187 LA-NPC patients who received C-CRT were retrospectively analyzed. The GLUCAR index was defined as 'GLUCAR = (Fasting Glucose x CRP/Albumin Ratio) by utilizing measures of glucose, C-reactive protein (CRP), and albumin obtained on the first day of C-CRT. Results: The optimal GLUCAR cutoff was 31.8 (area under the curve: 78.1%; sensitivity: 70.5%; specificity: 70.7%, Youden: 0.412), dividing the study cohort into two groups: GLUCAR < 1.8 (N = 78) and GLUCAR >= 31.8 (N = 109) groups. A comparison between the two groups found that the tooth extraction rate was significantly higher in the group with a GLUCAR >= 31.8 (84.4% vs. 47.4% for GLUCAR < 31.8; odds ratio (OR):1.82; p < 0.001). In the univariate analysis, the mean mandibular dose >= 38.5 Gy group (76.5% vs. 54.9% for <38.5 Gy; OR: 1.45; p = 0.008), mandibular V55.2 Gy group >= 40.5% (80.3 vs. 63.5 for <40.5%, p = 0.004, OR; 1.30), and being diabetic (71.8% vs. 57.9% for nondiabetics; OR: 1.23; p = 0.007) appeared as the additional factors significantly associated with higher tooth extraction rates. All four characteristics remained independent predictors of higher tooth extraction rates after C-CRT in the multivariate analysis (p < 0.05 for each). Conclusions: The GLUCAR index, first introduced here, may serve as a robust new biomarker for predicting post-C-CRT tooth extraction rates and stratifying patients according to their tooth loss risk after treatment.
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    High Pre-Chemoradiotherapy Pan-Immune-Inflammation Value Levels Predict Worse Outcomes in Patients with Stage IIIB/C Non-Small-Cell Lung Cancer
    (2023) Topkan, Erkan; Kucuk, Ahmet; Ozkan, Emine Elif; Ozturk, Duriye; Besen, Ali Ayberk; Mertsoylu, Huseyin; Pehlivan, Berrin; Selek, Ugur; 0000-0001-8120-7123; 38091179; AAG-2213-2021
    Background and objectives We explored the prognostic usefulness of the pan-immune-inflammation value (PIV) in patients with stage IIIB/C non-small-cell lung cancer (NSCLC) who underwent concurrent chemoradiotherapy (CCRT).Methods and patients For all patients, the PIV was calculated using platelet (P), monocyte (M), neutrophil (N), and lymphocyte (L) measures obtained on the first day of CCRT: PIV = P x M x N divided by L. Using receiver operating characteristic (ROC) curve analysis, we searched for the existence of an ideal cutoff that may partition patients into two groups with unique progression-free- (PFS) and overall survival (OS) results. The primary endpoint of this retrospective cohort research was to determine whether there were any significant relationships between pretreatment PIV measures and post-CCRT OS outcomes.Results The present research included a total of 807 stage IIIB/C NSCLC patients. According to ROC curve analysis, the ideal PIV cutoff was 516 [area under the curve (AUC): 67.7%; sensitivity: 66.4%; specificity: 66.1%], which divided the whole cohort into two: low PIV (L-PIV: PIV < 516; N = 436) and high PIV (H-PIV: PIV >= 516; N = 371). The comparisons between the PIV groups indicated that either the median PFS (9.2 vs. 13.4 months; P < 0.001) or OS (16.7 vs. 32.7 months; P < 0.001) durations in the H-PIV group were substantially inferior to their L-PIV counterpart. Apart from the H-PIV (P < 0.001), the N-3 nodal stage (P = 0.006), IIIC disease stage (P < 0.001), and receiving only one cycle of concurrent chemotherapy (P = 0.005) were also determined to be significant predictors of poor PFS (P < 0.05, for each) and OS (P < 0.05, for each) outcomes in univariate analysis. The multivariate analysis findings revealed that all four variables had independent negative impacts on PFS (P < 0.05, for each) and OS (P < 0.05, for each).Conclusions The findings of this hypothesis-generating retrospective analysis claimed that the novel PIV was an independent and steadfast predictor of PFS and OS in stage IIIB/C NSCLC patients.
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    The Prognostic Value of the Novel Global Immune-Nutrition-Inflammation Index (GINI) in Stage IIIC Non-Small Cell Lung Cancer Patients Treated with Concurrent Chemoradiotherapy
    (2023) Topkan, Erkan; Selek, Ugur; Pehlivan, Berrin; Kucuk, Ahmet; Ozturk, Duriye; Ozdemir, Beyza Sirin; Besen, Ali Ayberk; Mertsoylu, Huseyin; 0000-0001-8120-7123; 37760482; AAG-2213-2021
    Simple Summary: We investigated the prognostic significance of the newly created Global Immune-Nutrition-Inflammation Index (GINI) in IIIC non-small cell lung cancer (NSCLC) patients who received definitive concurrent chemoradiotherapy (CCRT). A total of 802 newly diagnosed stage IIIC NSCLC patients were included. The optimal pre-CCRT GINI cutoff was 1562 (area under the curve: 76.1%; sensitivity: 72.4%; specificity: 68.2%; Youden index: 0.406). GINI >= 1562 was associated with significantly shorter median locoregional progression-free (p < 0.001), progression-free (p < 0.001), and overall survival (p < 0.001) than GINI < 1562. For each survival endpoint, the association between GINI and survival outcomes appeared independent of other confounding variables (p < 0.05 for each). The novel GINI index effectively stratified patients with stage IIIC NSCLSC into two distinct subgroups, demonstrating significant differences in both median and long-term survival rates. Background: We sought to determine the prognostic value of the newly developed Global Immune-Nutrition-Inflammation Index (GINI) in patients with stage IIIC non-small cell lung cancer (NSCLC) who underwent definitive concurrent chemoradiotherapy (CCRT). Methods: This study was conducted on a cohort of 802 newly diagnosed stage IIIC NSCLC patients who underwent CCRT. The novel GINI created first here was defined as follows: GINI = [C-reactive protein x Platelets x Monocytes x Neutrophils] divided by [Albumin x Lymphocytes]. The receiver operating characteristic (ROC) curve analysis was used to determine the optimal pre-CCRT GINI cut-off value that substantially interacts with the locoregional progression-free (LRPFS), progression-free (PFS), and overall survival (OS). Results: The optimal pre-CCRT GINI cutoff was 1562 (AUC: 76.1%; sensitivity: 72.4%; specificity: 68.2%; Youden index: 0.406). Patients presenting with a GINI >= 1562 had substantially shorter median LRPFS (13.3 vs. 18.4 months; p < 0.001), PFS (10.2 vs. 14.3 months; p < 0.001), and OS (19.1 vs. 37.8 months; p < 0.001) durations than those with a GINI < 1562. Results of the multivariate analysis revealed that the pre-CCRT GINI >= 1562 (vs. <1562), T4 tumor (vs. T3), and receiving only 1 cycle of concurrent chemotherapy (vs. 2-3 cycles) were the factors independently associated with poorer LRPS (p < 0.05 for each), PFS (p < 0.05 for each), and OS (p < 0.05 for each). Conclusion: The newly developed GINI index efficiently divided the stage IIIC NSCLSC patients into two subgroups with substantially different median and long-term survival outcomes.
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    Definitive Chemoradiation Therapy Following Surgical Resection or Radiosurgery Plus Whole-Brain Radiation Therapy in Non-Small Cell Lung Cancer Patients With Synchronous Solitary Brain Metastasis: A Curative Approach
    (2014) Parlak, Cem; Mertsoylu, Huseyin; Guler, Ozan Cem; Onal, Cem; Topkan, Erkan; https://orcid.org/0000-0001-6170-0383; https://orcid.org/0000-0002-1932-9784; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-8120-7123; 24495594; B-3671-2014; M-9530-2014; AAC-5654-2020; HOC-5611-2023; AAG-2213-2021
    Purpose/Objectives: The aim of this study was to evaluate the impact of definitive thoracic chemoradiation therapy following surgery or stereotactic radiosurgery (SRS) and whole-brain radiation therapy (WBRT) on the outcomes of patients with non-small cell lung cancer (NSCLC) with synchronous solitary brain metastasis (SSBM). Methods and Materials: A total of 63 NSCLC patients with SSBM were retrospectively evaluated. Patients were staged using positron emission tomography-computed tomography in addition to conventional staging tools. Thoracic radiation therapy (TRT) with a total dose of 66 Gy in 2 Gy fractions was delivered along with 2 cycles of cisplatin-based chemotherapy following either surgery plus 30 Gy of WBRT (n = 33) or SRS plus 30 Gy of WBRT (n = 30) for BM. Results: Overall, the treatment was well tolerated. All patients received planned TRT, and 57 patients (90.5%) were also able to receive 2 cycles of chemotherapy. At a median follow-up of 25.3 months (7.1-52.1 months), the median months of overall, locoregional progression-free, neurological progression-free, and progression-free survival were 28.6, 17.7, 26.4, and 14.6, respectively. Both univariate and multivariate analyses revealed that patients with a T1-T2 thoracic disease burden (P = .001), a nodal stage of N0-N1 (P = .003), and no weight loss (P = .008) exhibited superior survival. Conclusions: In the present series, surgical and radiosurgical treatments directed toward SSBM in NSCLC patients were equally effective. The similarities between the present survival outcomes and those reported in other studies for locally advanced NSCLC patients indicate the potentially curative role of definitive chemoradiation therapy for highly selected patients with SSBM. (C) 2014 Elsevier Inc.
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    Safety and Palliative Efficacy of Single-Dose 8-Gy Reirradiation for Painful Local Failure in Patients with Stage IV Non-Small Cell Lung Cancer Previously Treated with Radical Chemoradiation Therapy
    (2015) Topkan, Erkan; Yildirim, Berna Akkus; Guler, Ozan Cem; Parlak, Cem; Pehlivan, Berrin; Selek, Ugur; 0000-0001-8120-7123; 0000-0001-6170-0383; 0000-0001-6661-4185; 0000-0001-6908-3412; 0000-0001-8087-3140; 25752391; AAG-2213-2021; B-3671-2014; V-5717-2017; AAC-5654-2020; O-5474-2014
    Purpose: To investigate the safety and efficacy of single-dose 8-Gy palliative chest reirradiation (CRI) in metastatic non-small cell lung cancer (M-NSCLC) patients with painful thoracic failures (TF) within the previous radiation portal. Patients and Methods: We retrospectively analyzed the clinical data of 78 M-NSCLC patients who received single-dose 8-Gy CRI for painful TF after concurrent chemoradiation therapy to a total radiation dose of 52 to 66 Gy between 2007 and 2012. Primary endpoints included significant pain relief (SPR) defined as a >= 2 point decrement in the Visual Analogue Scale for Pain inventory (VAS-P), time to pain relief, and duration of pain control. Secondary objectives were survival and prognostic factors. Results: Treatment was well tolerated, with only 5.1% grade 3 pneumonitis and 1.3% grade 2 esophagitis. Pre-CRI median and post-CRI minimum VAS-P were 7 and 3 (P < .001), respectively. SPR was noted in 67 (85.9%) patients, and only 3 (3.9%) scored progressive pain. Median time to lowest VAS-P and duration of pain control were 27 days and 6.1 months, respectively. Median overall survival (OS) was 7.7 months, and the 1-year OS rate was 26.5%. On multivariate analyses, lower Eastern Cooperative Oncology group score (1-2; P < .001), absence of anemia (P = .001), and fewer metastatic sites (1-2; P < .001) were found to be associated with longer OS. Conclusions: Single-dose 8-Gy CRI provides safe, effective, and durable pain palliation for TF in radically irradiated M-NSCLC patients. Because of its convenience, lower cost, and higher comfort, the present protocol can be considered an appropriate option for patients with limited life spans. (C) 2015 Elsevier Inc.
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    Prevention of Radiation-Induced Retinopathy with Amifostine in Wistar Albino Rats
    (2015) Yildirim, Berna Akkus; Cetin, Eren; Topkan, Erkan; Ozyigit, Gokhan; Cengiz, Mustafa; Surucu, Selcuk; Usubutun, Alp; Akyol, Fadil; 0000-0001-6661-4185; 25768249; V-5717-2017
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    Reproducible Deep-Inspiration Breath-Hold Irradiation with Forward Intensity-Modulated Radiotherapy for Left-Sided Breast Cancer Significantly Reduces Cardiac Radiation Exposure Compared To Inverse Intensity-Modulated Radiotherapy
    (2014) Bolukbasi, Yasemin; Saglam, Yucel; Selek, Ugur; Topkan, Erkan; Kataria, Anglina; Unal, Zeynep; Alpan, Vildan; https://orcid.org/0000-0001-8120-7123; 24852861; AAG-2213-2021
    Aims and background. To investigate the objective utility of our clinical routine of reproducible deep-inspiration breath-hold irradiation for left-sided breast cancer patients on reducing cardiac exposure. Methods and study design. Free-breathing and reproducible deep-inspiration breath-hold scans were evaluated for our 10 consecutive left-sided breast cancer patients treated with reproducible deep-inspiration breath-hold. The study was based on the adjuvant dose of 50 Gy in 25 fractions of 2 Gy/fraction. Both inverse and forward intensity-modulated radiotherapy plans were generated for each computed tomography dataset. Results. Reproducible deep-inspiration breath-hold plans with forward intensity-modulated radiotherapy significantly spared the heart and left anterior descending artery compared to generated free-breathing plans based on mean doses free-breathing vs reproducible deep-inspiration breath-hold, left ventricle (296.1 vs 94.5 cGy, P = 0.005), right ventricle (158.3 vs 59.2 cGy, P = 0.005), left anterior descending artery (171.1 vs 78.1 cGy, P = 0.005), and whole heart (173.9 vs 66 cGy, P = 0.005), heart V20 (2.2% vs 0%, P = 0.007) and heart V10 (4.2% vs 0.3%, P = 0.007) whereas they revealed no additional burden on the ipsilateral lung. Reproducible deep-inspiration breath-hold and free-breathing plans with inverse intensity-modulated radiotherapy provided similar organ at risk sparing by reducing the mean doses to the left ventricle, left anterior descending artery, heart, V10-V20 of the heart and right ventricle. However, forward intensity-modulated radiotherapy showed significant reduction in doses to the left ventricle, left anterior descending artery, heart, right ventricle, and contralateral breast (mean dose, 248.9 to 12.3 cGy, P= 0.005). The mean doses for free-breathing vs reproducible deep-inspiration breath-hold of the proximal left anterior descending artery were 1.78 vs 1.08 Gy and of the distal left anterior descending artery were 8.11 vs 3.89 Gy, whereas mean distances to the 50 Gy isodose line of the proximal left anterior descending artery were 6.6 vs 3.3 cm and of the distal left anterior descending artery were 7.4 vs 4.1 cm, with forward intensity-modulated radiotherapy. Overall reduction in mean doses to proximal and distal left anterior descending artery with deep-inspiration breath-hold irradiation was 39% (P = 0.02) and 52% (P = 0.002), respectively. Conclusions. We found a significant reduction of radiation exposure to the contralateral breast, left and right ventricles, as well as of proximal and especially distal left anterior descending artery with the deep-inspiration breath-hold technique with forward intensity-modulated radiotherapy planning.
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    Retrospective Comparison of Standard and Escalated Doses of Radiotherapy in Newly Diagnosed Glioblastoma Patients Treated with Concurrent and Adjuvant Temozolomide
    (2019) Guler, Ozan Cem; Yildirim, Berna Akkus; Onal, Cem; Topkan, Erkan; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0001-6661-4185; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-8120-7123; 30950447; AAC-5654-2020; V-5717-2017; HOC-5611-2023; AAG-2213-2021
    BACKGROUND: To compare the efficacies of standard dose-(SDRT) and escalated dose radiotherapy (EDRT) in newly diagnosed glioblastoma (GBM) with concurrent and adjuvant temozolomide (TMZ). MATERIALS AND METHODS: Outcomes of 126 newly diagnosed GBM patients who received SDRT (60 Gy, 30 fractions) or EDRT (70 Gy, 30 fractions) with concurrent plus adjuvant TMZ were retrospectively analyzed. Both groups received concurrent TMZ (75 mg/m(2)) during the course of RT and at least one course of adjuvant TMZ (150-200 mg/m(2)), thereafter. Overall survival (OS) and local progression free survival (LPFS) constituted the primary and secondary endpoints, respectively. RESULTS: At median 14.2 months follow-up, 26 (20.6%) patients were alive. Median LPFS and OS were 9.2 [95% confidence interval (CI); 8.4-10.0] and 15.4 months (95% CI; 12.1-18.8), respectively, for the entire cohort. Although the median OS was numerically superior in the EDRT this difference could not reach statistical significance (22.0 vs. 14.9 months; P = 0.45), Likewise, LPFS was also (9.9 vs. 8.9 months; P = 0.89) not different between the two treatment groups. In multivariate analysis, better recursive partitioning analysis class (3-4 vs. 5; P = 0.044) and extensive surgery (gross total resection vs. subtotal resection/biopsy only; P = 0.021) were identified to associate significantly with superior OS times, irrespective of the RT protocol. CONCLUSIONS: Although the current median OS of 22 months of the EDRT group is promising, no statistically significant survival advantage for EDRT was observed even in the presence of TMZ. Randomized studies with larger population sizes and available genetic markers are warranted to conclude more reliably on the fate of EDRT plus TMZ.