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Öğe Chemotherapy and cerebrovascular disease(Zerbinis Medical Publ, 2008) Saynak, M.; Cosar-Alas, R.; Yurut-Caloglu, V.; Caloglu, M.; Kocak, Z.; Uzal, C.Cerebrovascular disease is common in cancer patients. Some tumors are at high risk for cerebrovascular complications. The development of cerebrovascular disease may be provoked by cancer treatment. No well-planned prospective studies about other causes of thrombosis are available, although various case reports about thrombosis related to chemotherapy have been published. L-asparaginase, cisplatin, 5-fluorouracil (5-FU) and methotrexate are anticancer agents which are reported to relate to stroke. The mechanisms by which antineoplastic agents may lead to stroke include endothelium toxicity and abnormalities of coagulation factors. Also, brain hemorrhages that could result from chemotherapy effects on the hemostatic system were reported. Besides, it is difficult to determine whether stroke is caused by chemotherapy or cancer itself Clinicians deal not only with problems originating from cancer itself but also with the complications resulting from its treatment. Treatment-induced cerebrovascular disorders affect quality of life and survival in cancer patients. For this reason, cancer treatment should be planned by taking into consideration the possibility of cerebrovascular complications.Öğe CYCLIN D1 (A870G) GENE POLYMORPHISM IN LUNG CANCER(Elsevier Ireland Ltd, 2011) Cakina, S.; Gulyasar, T.; Sipahi, T.; Ozen, A.; Kocak, Z.[Abstract Not Available]Öğe Effect of bladder distention on bladder base dose in gynaecological intracavitary high dose rate brachytherapy(British Inst Radiology, 2009) Adli, M.; Garipagaoglu, M.; Kocak, Z.The purpose of this study was to assess the impact of bladder volume on bladder base doses during gynaecological intracavitary high dose rate (HDR) brachytherapy. 42 different intracavitary HDR brachytherapy applications (tandem and ovoid, 25; ovoid, 17) were performed in 41 patients treated for cervical (n=29) and endometrial (n=12) cancer. The International Commission on Radiation Units and Measurements (ICRU) bladder reference point (BRP) dose and doses of 17 points selected on the bladder base were calculated using planning orthogonal radiographs taken after applicator placement with 100 ml and 270 ml bladder volumes. The effect of bladder volume on ICRU BRP and bladder base maximum point (BBMP) doses were analysed for both types of applications. Median ICRU BRP doses (in percentage of prescription dose) were 36.2% (18.2-69.8%) and 40.0% (21.0-61.8%) for ovoid applications (p=0.13) and 34.9% (15.7-81.0%) and 33.8% (16.5-88.1%) for tandem and ovoid applications (p=0.48) in 100 ml and 270 ml bladder volumes, respectively. Median BBMP doses were 75.1% (33.8-141.0%) and 104.0% (62.8-223.0%) for ovoid applications (p < 0.001) and 116% (51.2-242.0%) and 124.0% (62.0-326%) for tandem and ovoid applications (p=0.018) in 100 ml and 270 ml bladder volumes, respectively. Although the BBMP dose significantly increases, the ICRU BRP dose does not change with increasing bladder volume in gynaecological intracavitary HDR brachytherapy. Increasing bladder volume increases bladder base maximum dose in intracavitary gynaecological brachytherapy.Öğe The effect of gender differences on radiation induced acute lung toxicity by using XRCC1, XRCC3 and HHR2L gene panel(Elsevier Ireland Ltd, 2015) Ozen, A.; Cakina, S.; Turkkan, G.; Cosar, R.; Sipahi, T.; Kocak, Z.; Uzal, C.[Abstract Not Available]Öğe GIANT INTRATHORACIC MASSES AS AN ECTOPIC THYMOMA TREATED WITH CHEMORADIOTHERAPY(Wiley-Blackwell, 2016) Kocak, Z.; Okumus, D.; Erdogan, B.; Tastekin, E.; Karamustafaoglu, A.[Abstract Not Available]Öğe High plasma d-dimer level is associated with decreased survival in patients with lung cancer(Elsevier Science London, 2007) Altiay, G.; Ciftci, A.; Demir, M.; Kocak, Z.; Sut, N.; Tabakoglu, E.; Hatipoglu, O. N.Aims: An elevated plasma D-dimer level indicates the activation of coagulation and fibrinolysis. In the present study, we investigated the association of pre-treatment haemostatic parameters (D-dimer, fibrinogen and prothrombin fragment 1 + 2) with clinicopathological parameters and outcome in patients with lung cancer. Materials and methods: Plasma levels Of D-dimer and other parameters were measured in 78 evaluable patients with lung cancer (60 non-small cell lung cancers, 18 small cell lung cancers). At diagnosis, 35 patients (44.9%) were locally advanced stage (IIIA/B) and 43 patients (55.1%) had metastatic disease (IV). Multivariate statistical analysis was carried out using Cox's proportional hazards model. The receiver operating characteristic curve was used to determine the cutoff values for D-dimer, fibrinogen and prothrombin fragment 1 + 2. Results: The median survival for all patients was 264 days (95% confidence interval 200-328 days). A significant association between the plasma levels Of D-dimer and the response to chemotherapy was observed (P = 0.03). With the univariate analysis, tumour stage, pre-treatment plasma levels Of D-dimer, fibrinogen, platelet count, lactate dehydrogenase concentration and Karnofsky performance status were predictive for survival. With the multivariate analysis (P <= 0.11), the plasma level Of D-dimer (P < 0.001), tumour stage (P = 0.01) and Karnofsky performance status (P = 0.02) were identified as independent predictive factors. The median survival times were 405 days (95% confidence interval 165-644 days) and 207 days (95% confidence interval 146-267 days, P < 0.001), respectively, for patients with a low D-dimer level (<= 0.65 mu g/ml) and a high D-dimer level (> 0.65 mu g/ml). Conclusions: Elevated plasma levels Of D-dimer in patients with lung cancer are associated with decreased survival and a poor response to treatment. Pre-treatment for the D-dimer level may be useful in the prediction of survival and the response to treatment.Öğe Investigation of differences of sacral and vertebral bone mineral densities before and after radiotherapy in patients with locally advanced rectal cancer(Elsevier, 2019) Hayar, M.; Durankus, N. K.; Altun, G. D.; Kocak, Z.; Uzal, M. C.; Saynak, M.Purpose. - Radiotherapy is a treatment method performed using ionizing radiation on cancer patients either alone or with surgery and/or chemotherapy. Although modern radiotherapy techniques provide a significant advantage in protecting healthy tissues, it is inevitable that normal tissues are also located in the areas targeted by radiations. In this study, we aimed to examine the bone mineral density changes in bone structures commonly included in the irradiated area such as, L5 vertebra, sacrum, and femur heads, in patients who have received pelvic radiotherapy; and the relationship between these changes with radiation dose. Material and methods. - Patients included in the study had been previously diagnosed with rectal cancer, which were operated or not. Preoperative or postoperative pelvic radiotherapy was planned for all patients. In terms of convenience when comparing with future scans, all densitometry and CT scans were performed with the same devices. Fifteen patients were included in the study. In order to determine the dose of radiation each identified area had taken after radiotherapy, the sacrum, L5 vertebra, bilateral femoral heads, and L1 regions were contoured in the CT scans in which treatment planning was done. Sagittal cross-sectional images were taken advantage of while these regions were being contoured. Results. - Bone mineral density was evaluated with CT and dual-energy X-ray absorptiometry before and after the treatment. The regions that have theoretically been exposed to irradiation, such as L5, sacrum, left to right femur were found to have significant difference in terms of bone density. According to CT evaluation, there was a significant decrease in bone intensity of L5, sacrum, left and right femurs. Dual energy X-ray absorptiometry assessment revealed that the whole of the left femoral head, left femur neck and Ward's region were significantly affected by radiotherapy. However, there was no significant difference in the sacrum and L5 vertebra before and after radiotherapy. Conclusion. - More accurate results could be achieved if the same study was conducted on a larger patient population, with a longer follow-up period. When the reduction in bone density is at maximum or a cure is likely in a long-term period, bone mineral density could be determined by measurements performed at regular intervals. (C) 2019 Societe francaise de radiotherapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.Öğe Massive osteoradionecrosis of facial bones and soft tissues(Imprimatur Publications, 2009) Benlier, E.; Alicioglu, B.; Kocak, Z.; Yurdakul-Sikar, E.; Top, H.Osteoradionecrosis (ORN) is one of the most serious and uncommon complications in head and neck irradiation for cancer It is defined as a combination of necrotic soft tissue and bone not being able to heal spontaneously, it demonstrates a general resistance to antibiotics and requires conservative surgical management. Even with modern radiation therapy, its incidence is high v unpredictable and varies between 4-30%. We report on a patient with a huge open cavitation in the cheek, communicating with the mouth and extending to contralateral periodontal gingival and temporal fossa. He had been treated with radiation therapy for naso-pharyngeal cancer 5 years ago and presented with restriction of the opening of the mouth. Osteonecrosis complicated with osteomyelitis was evident in bilateral mandible and maxillary bones and the temporal bone. The ramus of the mandible and zygomatic arc were resected, subtotal maxillectomy was performed and the defect was repaired by a free double island flap from the scapular and parascapular osteocutaneous latissimus dorsi muscle flap supplied by subscapular artery. To our knowledge, this is the most extensive bone and soft tissue destruction due to radiation reported in the literature.Öğe Sudden death: A case report of hepatocellular carcinoma with tumor thrombus extending into the right atrium(Zerbinis Medical Publ, 2007) Saynak, M.; Ozen, A.; Kocak, Z.; Cosar-Alas, R.; Uzal, C.[Abstract Not Available]
