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BUĞDAYCI, ONUR

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    PublicationOpen Access
    A gaucher patient with bilateral total femoral lytic lesions mimicking malignancy: a case report
    (2022-01-01) AKGÜLLE, AHMET HAMDİ; BUĞDAYCI, ONUR; ERBARUT SEVEN, İPEK; KESKİN ÖZTÜRK, BEYZA; ŞAHBAT Y., AKGÜLLE A. H. , BUĞDAYCI O., ERBARUT SEVEN İ., KESKİN ÖZTÜRK B.
    Bone involvement in Gaucher disease can afect quality of life. Bone lesions of Gaucher disease can be confused with hematological diseases, infections, and malignancy. Our patient with bilateral femur involvement presented to us with a pathological fracture. After the fracture was treated with a long leg splint and healed, we performed a biopsy because of suspicious radiological fndings. The pathology results confrmed Gaucher disease with bone infltration during the time in which conservative follow-up was taking place, eventually leading to the patient’s mobilization again. Bone fndings of Gaucher disease indicate a difcult process requiring follow-up and treatment. It is crucial to scan patients periodically for possible vertebral and extremity symptoms. Vertebral and extremity fractures undoubtedly require experience on the part of the clinician as they can imitate malignant masses.
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    PublicationOpen Access
    Low bone density, vertebral fracture and FRAX score in kidney transplant recipients: A cross-sectional cohort study
    (PUBLIC LIBRARY SCIENCE, 2021-04-30) VELİOĞLU, ARZU; Velioglu, Arzu; Kaya, Burcu; Aykent, Basar; Ozkan, Bige; Karapinar, Melis Sevil; Arikan, Hakki; Asicioglu, Ebru; Bugdayci, Onur; Yavuz, Dilek Gogas; Tuglular, Serhan
    Background Kidney transplantation (KT) recipients are at increased risk of low bone density (LBD) and fractures. In this retrospective study, we investigated bone mineral density (BMD), vertebral fractures, calculated risk for major osteoporotic fractures (MOF), and hip fractures in the KT recipients. Patients-method Patients who completed at least one year after KT were included in the analysis. Demographic, clinical, and laboratory data were recorded. Measurements of BMD were performed by dual-energy X-ray absorptiometry. Vertebral fractures were assessed using semi-quantitative criteria with conventional radiography. The ten-year risk for MOF and hip fracture were calculated using the FRAX@ tool with BMD. Results One hundred fifty-three KT recipients were included in the study. The population included 77 women. The mean age at evaluation was 46,511,9 years. Seventy-eight (50.9%) patients had normal femoral neck BMD while osteoporosis and osteopenia at the femoral neck were present in 12 (7.8%) and 63 (41.1%) of the patients, respectively. Age at evaluation was the risk factor for LBD (OR 1.057; 95% CI 1.024-1.091; p = 0.001). In female KT recipients, LBD was principally affected by menopausal status whereas in males, mammalian target of rapamycin (mTOR) inhibitor use and lower BMI levels were the risk factors. The prevalent vertebral fracture was found in 43.4% of patients. In multivariate analysis, only steroid use (OR 0.121; 95% CI 0.015-0.988; p = 0.049) was found to be associated with prevalent fracture. Among all KT recipients, 1.9% had a high MOF probability (>= 20% risk of fracture), and 23.5% had high hip fracture probability (>= 3% risk of hip fracture) according to FRAX. Conclusion Exploring the prevalence of LBD and vertebral fracture and the risk factors would help clinicians to modify long-term follow-up strategies. Furthermore, the high hip fracture risk probability in our cohort suggested that there is a need for longitudinal studies to confirm the validity of the FRAX tool in the transplant population.
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    PublicationOpen Access
    The impact of sarcopenia and sarcopenic obesity on survival in children with Ewing sarcoma and osteosarcoma
    (2023-01-05) BUĞDAYCI, ONUR; Buğdaycı O., Eker N.
    Abstract Background Sarcopenia is an indicator of negative outcomes in many diseases in adults. Reports indicate this might also be true in children. Objective To evaluate the efect of sarcopenia and sarcopenic obesity on event-free survival (EFS) and overall survival (OS) in children with Ewing sarcoma and osteosarcoma. Materials and methods We retrospectively measured total muscle areas of the pectoralis, paraspinal (T12 level) and psoas (L4 level) muscles and total abdominal muscle area (L3 level) on computed tomography images in 60 children diagnosed with either Ewing sarcoma (n=34) or osteosarcoma (n=26). Skeletal muscle indices (SMI) were calculated by normalizing muscle area to patient height. Vertebral morphologic parameters of T12 and L4 vertebrae were measured and correlated to patient height to use as a substitute in cases of missing height data (SMIT12 and SMIL4). We calculated sarcopenic obesity index by dividing SMI by body mass index. We subdivided children into two groups according to the median value of each parameter and assessed the diferences in survival between the groups. Results No skeletal muscle index or sarcopenic obesity index parameter signifcantly afected event-free or overall survival in the total group analysis. In the non-metastatic group, higher values of SMI–paraspinal and SMIT12–psoas were correlated with longer event-free survival and no patient died in this group. Boys and children in the metastatic group with higher SMIT12–paraspinal values had signifcantly longer event-free survival and both event-free and overall survival, respectively. Conclusion Although some parameters were correlated with event-free and overall survival, neither sarcopenia nor sarcopenic obesity were reliably associated with survival in children with Ewing sarcoma or osteosarcoma.
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    PublicationOpen Access
    Dual-Phase ADC Modelling of Breast Masses in Diffusion-Weighted Imaging: Comparison with Histopathologic Findings
    (AVES, 2018-05-16) BUĞDAYCI, ONUR; Ertas, Gokhan; Onaygil, Can; Bugdayci, Onur; Aribal, Erkin
    Objective: To investigate the diagnostic value of dual-phase apparent diffusion coefficient (ADC) compared to traditional ADC values in quantitative diffusion-weighted imaging (DWI) for differentiating between benign and malignant breast masses. Materials and Methods: Diffusion-weighted images of pathologically confirmed 88 benign and 85 malignant lesions acquired using a 3.0T MR scanner were analyzed. Small region-of-interests focusing on the highest signal intensity of lesions were used. Lesion ADC estimates were obtained separately from all b-value images (ADC; b=50, 400 and 800s/mm(2)), lower b-value images (ADC low; b=50 and 400s/mm2) and higher b-value images (ADC(high); b=400 and 800s/mm(2)). A set of dual-phase ADC (dpADC) models were constructed using ADC low, ADC high and a perfusion influence factor ranging from 0 to 1. Results: Strong positive correlation is observable between ADC and all dpADCs (rho=0.80-1.00). Differences in ADC and dpADCs between the benign and the malignant lesions are all significant (p<0.05). In detecting malignancy, traditional lesion ADC provides a good performance (AUC=89.9%) however dpADC(0.5) (dpADC with a factor of 0.5) accomplishes a better performance (AUC=90.8%). At optimal thresholds, ADC achieves 94.1% sensitivity, 72.7% specificity and 83.2% accuracy while dpADC(0.5) leads to 92.9% sensitivity, 79.5% specificity and 86.1% accuracy. Conclusion: Dual-phase ADC modelling may improve the accuracy in breast cancer diagnosis using DWI. Further prospective studies are needed to justify its benefit in clinical setting.
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    PublicationOpen Access
    Gradient-boosting algorithm for microwave breast lesion classification-safe clinical investigation
    (2022-12-13) BUĞDAYCI, ONUR; Janjic A., Akduman I., Cayoren M., Bugdayci O., Aribal M. E.
    ) Background: Microwave breast imaging (MBI) is a promising breast-imaging technology that uses harmless electromagnetic waves to radiate the breast and assess its internal structure. It utilizes the difference in dielectric properties of healthy and cancerous tissue, as well as the dielectric difference between different cancerous tissue types to identify anomalies inside the breast and make further clinical predictions. In this study, we evaluate the capability of our upgraded MBI device to provide breast tissue pathology. (2) Methods: Only patients who were due to undergo biopsy were included in the study. A machine learning (ML) approach, namely Gradient Boosting, was used to understand information from the frequency spectrum, collected via SAFE, and provide breast tissue pathology. (3) Results: A total of 54 patients were involved in the study: 29 of them had benign and 25 had malignant findings. SAFE acquired 20 true-positive, 24 true-negative, 4 false-positive and 4 false-negative findings, achieving the sensitivity, specificity and accuracy of 80%, 83% and 81%, respectively. (4) Conclusions: The use of harmless tissue radiation indicates that SAFE can be used to provide the breast pathology of women of any age without safety restrictions. Results indicate that SAFE is capable of providing breast pathology at a high rate, encouraging further clinical investigations.
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    PublicationOpen Access
    Effect of denosumab treatment on bone mineral density and bone turnover markers in osteoporotic patients: real-life experience 2-year follow-up
    (2022-12-01) DİNÇER YAZAN, CEYDA; BUĞDAYCI, ONUR; ILGIN, CAN; YAVUZ, DİLEK; DİNÇER YAZAN C., BUĞDAYCI O., ILGIN C., YAVUZ D.
    Summary Denosumab leads to improvements in BMD levels and is a well-tolerated agent according to results of randomized controlled studies but results in real-life setting are important to evaluate drug adherence and real-life efciency. In this study, we present the results of 305 patients that were treated with denosumab in our clinic. Introduction The long-term efcacy of anti-osteoclastic drugs in treatment of osteoporosis is well known. Denosumab, a novel human monoclonal antibody, is an anti-osteoclastic agent that has been shown to lead to reductions in vertebral, nonvertebral, and hip fracture risk in randomized and observational studies. Real-life data of this agent is increasing. In this study, we presented our real-life data about the 2-year follow-up of patients under denosumab treatment. Methods Osteoporotic patients who were treated with at least one denosumab injection between 2014 and 2020 years were included. Clinical and demographic data, bone turnover markers, and radiological reports (bone mineral densitometry (BMD), vertebral x-ray) were obtained from patient fles retrospectively. Results A total of 305 patients (f/m: 275/30, 68.1±11.05 years) were included. The median injection number was 4 (1–10). Two hundred seventy-three patients (89.8%) were persistent on treatment at the 12th month; 175 patients (57.3%) were persistent at 24th month. Sixty-eight patients (22%) were not using denosumab anymore, 55 of the patients were not continuing by doctor desicion and 13 were not continuing due to patient-related causes. Median BMD levels signifcantly increased from 0.809 (0.2–1.601, IQR: 0.136) to 0.861 (0.517–1.607, IQR: 0.14) in L1–L4 and from 0.702 (0.349–0.997, IQR: 0.125) to 0.745 (0.508–1.008, IQR: 0.137) in femur area at the 24th month of treatment. An improvement of 8.04% in L1–L4 BMD and 4.5% in femur neck BMD levels at the 24th month of treatment was observed. There was a signifcant decrease in bone turnover markers at the 24th month of treatment. Conclusion In our group of patients under denosumab treatment, 53% of persistence was found at 24 months and associated with improvement in BMD levels without any signifcant side efects except one case with urticarial reaction. Denosumab leads to improvements in BMD levels and is a well-tolerated agent in a real-life setting comparable to results of randomized controlled studies in patients with diferent comorbidities.
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    PublicationOpen Access
    A very rare case of cervicothoracic vertebral synostosis spanning eight adjacent segments: congenital vs acquired
    (MARMARA UNIV, FAC MEDICINE, 2018-02-26) BUĞDAYCI, ONUR; Cengic, Ismet; Tureli, Derya; Altas, Hilal; Bugdayci, Onur
    An elderly female presented with acute post-traumatic neck pain. Cervical roentgenogram revealed a long-segment cervicothoracic vertebral fusion spanning 8 adjacent spinal levels. The patient was evaluated with computed tomography (CT) and magnetic resonance (MR) imagings of the spine, electromyography (EMG) and growth differentiation factor 6 (GDF6) gene mutation analysis. Imaging findings were atypical for congenital block vertebrae and there was no GDF6 mutation. A revision of very old medical records and patient's recollections revealed long-term stay in sanatorium for rehabilitation of chronic partially-treated brucella spondylodiscitis during adolescence. Block vertebrae spanning several levels have previously been reported; but, this is the first report of an acquired cervicothoracic fusion spanning 8 adjacent vertebral bodies.
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    PublicationOpen Access
    Clinicopathologic and radiologic characteristics of pleomorphic lobular breast cancer
    (2021-01-01) KAYA, HANDAN; BUĞDAYCI, ONUR; UĞURLU, MUSTAFA ÜMİT; ARIKAN R., AKIN TELLİ T., ALAN Ö., DEMİRCAN N. C. , BAŞOĞLU T., ERCELEP Ö., KAYA H., BUĞDAYCI O., UĞURLU M. Ü. , ÖZGEN Z., et al.
    Objectives: The objective of the study was to evaluate clinicopathologic and radiologic features of patients with pleomorphic lobular breast cancer (pleomorphic lobular carcinoma [PLC]). Methods: We retrospectively evaluated the clinicopathologic and radiologic features of 25 PLC patients treated in our division from 2012 to 2018. Results: Median age was 50 (range, 42–55) and 48% were postmenopausal. The presence of spiculated mass was 92%. Median tumor size was 21.9 mm (SD±12.7 mm) and axillary lymph node positivity was 44%. Frequency of microcalcification was 12% and frequency of occult breast cancer was 8%. About 72% of patients had Stage 2 or 3 disease. De novo metastatic disease was 8% and another 8% developed metastasis during follow-up. ER, PR, and Her2/neu were positive in 76%, 44%, and 8%, respectively, and 16% of patients were triple negative. All tumors were Grade III. Median Ki-67 was 22% (range 3–90%). Frequency of lymphovascular invasion was 52%. Patients were followed median of 34.5 months (95% CI, 22.2–46.8), since during this period, two patients recurred and five died, median disease-free survival and overall survival could not be reached. Conclusion: Our data suggest that patients with PLC present with poor prognostic features such as large tumor size, axillary lymph node positivity, and high lymphovascular invasion and tumor grade and Ki-67
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    PublicationOpen Access
    Acetazolamide treatment in a patient with pseudohypoparathyroidism with venous calcification
    (2021-09-22) BUĞDAYCI, ONUR; GÜRAN, TÜLAY; BEREKET, ABDULLAH; DEMİRCİOĞLU, SERAP; SEVEN MENEVŞE T., GÜRPINAR TOSUN B., YAVAŞ ABALI Z., HELVACIOĞLU D., KAYGUSUZ S. B., ELTAN M., BUĞDAYCI O., GÜRAN T., BEREKET A., DEMİRCİOĞLU S.
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    PublicationOpen Access
    Prevalence of vertebral fractures and serum sclerostin levels in acromegaly
    (SPRINGER, 2021-09) YAVUZ, DİLEK; Uygur, Meliha Melin; Yazici, Dilek Dereli; Bugdayci, Onur; Yavuz, Dilek Gogas
    Objective An increased prevalence of vertebral fractures (VFs) has been reported in previous studies. The aim of this study was to evaluate the association between bone mineral density (BMD), bone turnover markers, serum sclerostin levels, and vertebral fractures (VFs) in acromegaly patients. We also evaluated the effects of gonadal status, disease activity, treatment modality, age, sex, and body mass index (BMI) on skeletal endpoints. Design Case-control study. Patients and measurements Seventy acromegaly patients (M/F:36/34, mean age 45.5 +/- 11.9 years) and 70 controls (M/F:31/39; mean age 45.66 +/- 11.9 years) were included. VFs, BMD, calcium metabolism, markers of bone turnover, and sclerostin levels were evaluated. BMD was measured by dual-energy X-ray absorptiometry (Hologic QDR 4500). Conventional lateral radiography of the spine was performed and the Genant method was used for the assessment of fractures of T4-L5 vertebrae. Results The prevalence of vertebral fractures was higher in acromegalic patients as compared with the control group (72.9 vs. 20%; p < 0.001). Serum phosphate (P) levels (3.46 +/- 0.59 mg/dl vs. 3.11 +/- 0.44 mg/dl; p < 0.001) and b-cross laps (CTx) levels (0.47 mu g/l, range 0.04-2.38 vs. 0.28 mu g/l, range 0.11-0.80; p < 0.001) were significantly higher in acromegaly patients than control subjects. Serum sclerostin levels were similar between either acromegaly patients and control subjects or acromegaly patients with VF and without VF. In the means of treatment modality, VFs were more frequent in patients treated with adjuvant gamma knife radiosurgery (GKS) (p = 0.07). In the binary logistic regression analysis, the age of the acromegaly patients, the presence of hypogonadism, and GKS treatment were the factors significantly correlated with the occurrence of spinal fractures. Conclusions The prevalence of VFs in patients with acromegaly is higher than in control subjects. Since advanced age, the presence of hypogonadism and GKS treatment were the factors predicting VFs in acromegaly; radiological evaluations should be considered as an emerging tool especially in those patients. Although markers of bone turnover elevated in acromegaly, they were not useful for the prediction of fractures. Serum sclerostin levels showed no discrepancy between the two groups and further studies are required for assessment of sclerostin role in this form of secondary osteoporosis.