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Featured researches published by Gorkem Aksu.


Journal of Cranio-maxillofacial Surgery | 2009

The role of surgery and radiotherapy in treatment of soft tissue sarcomas of the head and neck region: Review of 30 cases

Merdan Fayda; Gorkem Aksu; Fulya Yaman Agaoglu; Ahmet Karadeniz; Emin Darendeliler; Musa Altun; Gunter Hafiz

BACKGROUND Thirty adult patients with head and neck soft tissue sarcoma (HNSTS) treated between 1987 and 2000 were retrospectively analysed. PATIENTS AND METHODS The most frequent histopathological subtypes were chondrosarcomas (27%) and malignant fibrous histiocytoma (20%). The surgical resection was performed in 25 of the 30 patients (83%). Twenty-three patients in the surgical resection arm received postoperative radiotherapy. RESULTS Five-year local control rates for patients with negative surgical margins (n=9), microscopically positive disease (n=10), gross residual disease (n=6) and inoperable cases (n=5) were 64, 70, 20 and 0%, respectively. However, there was no significant difference in local control between patients with negative or microscopically positive disease who received postoperative radiotherapy (71 vs. 70%). The patients who received doses>or=60 Gy had significantly higher local control rates than the ones who received doses lower than 60 Gy (p=0.048). The local control rates were lower in patients with grade 2-3 tumours when compared with grade 1 tumours (44 vs. 83%). The median overall survival of whole group was 31 months. Median survivals of patients receiving both surgery and radiotherapy with negative and microscopically positive margins were significantly better than patients who were not treated with surgery (34.8 and 36 vs. 13.3 months). CONCLUSION Our results confirm that the optimal treatment of HNSTSs is complete surgical excision, and that postoperative adjuvant radiotherapy clearly improves local control.


American Journal of Clinical Oncology | 2004

Prognostic features and survival of inoperable hepatocellular carcinoma in Turkish patients with cirrhosis

Burak Sakar; Zeki Ustuner; Hakan Karagol; Gorkem Aksu; Hakan Camlica; N. Faruk Aykan

Background:Primary hepatocellular carcinoma (HCC) is common in Turkey and its prognosis is poor. In the current study the authors analyzed the prognostic factors and survival in Turkish patients with inoperable HCC with cirrhosis. Methods:Clinical and demographic data of 91 patients consecutively admitted to the authors’ institute from 1988 to 2000 were reviewed. A univariate analysis was performed using the Kaplan–Meier method to identify predictors of survival and were compared using the Mantel log-rank test. Independent factors correlated with survival were determined using the Cox regression analysis. Results:Cirrhosis was diagnosed in all patients. Coinfections with HCV and HBV were not observed. Overall median survival was 16.9 months. On univariate analysis, poor performance status (Eastern Cooperative Group); high α-fetoprotein (AFP); low albumin; high bilirubin; high alkaline phosphatase; high lactic dehydrogenase; high alanine and aspartate aminotransferase; high γ-glutamyl transpeptidase; high platelet count; low prothrombin activity; hepatitis B surface antigen positivity; the presence of ascites, encephalopathy, and portal vein thrombosis; poor differentiation and diffuse type of tumor; and no treatment were associated with shorter survival. Multivariate analysis showed that only independent risk factors were related to performance status (Eastern Cooperative Group) at initial presentation and with pathologic characteristic of the tumor: abnormal AFP level. Conclusion:HCC occurred only in patients with liver cirrhosis. Survival time can be predicted from information collected by the physician at the initial assessment.


Tumori | 2006

Primary glioblastoma multiforme in younger patients: a single-institution experience.

Cuneyt Ulutin; Merdan Fayda; Gorkem Aksu; Oguz Cetinayak; Okan Kuzhan; Fatih Ors; Murat Beyzadeoglu

Aims and Background To report our experience of patients with primary glioblastoma multiforme of young age by evaluating the characteristics, prognostic factors, and treatment outcomes. Patients and Methods Seventy patients with primary glioblastoma multiforme (GBM) treated at our department between 1996 and 2004 were studied. The male-female ratio was 2.6:1. The median age was 53 (16-74). Sixty-eight patients (97%) were operated on before radiotherapy and 2 patients (3%) underwent only stereotactic biopsy. All patients received radiotherapy. Postoperative chemotherapy as an adjuvant to radiotherapy was given to 9 patients (12%). The patients were divided into 2 groups according to their age (group A ≤35 years, n = 21 vs group B >35 years, n = 49). Survival was determined with the Kaplan-Meier method and differences were compared using the log-rank test. Cox regression analysis was performed to identify the independent prognostic factors. Karnofsky performance status (≥70 vs <70), age (≤35 vs >35 years), gender, tumor size (≤4 vs >4 cm), number of involved brain lobes (1 vs more than 1), type of surgery (total vs subtotal), preoperative seizure history (present vs absent), radiotherapy field (total cranium vs partial), total radiotherapy dose (60 vs 66 Gy), and adjuvant chemotherapy (present vs absent) were evaluated in univariate analysis. Results The median survival was 10.3 months in the whole group, 19.5 months in the younger age group and 5.7 months in the older age group. During follow-up re-craniotomy was performed in 2 patients (3%), and 1 patient (1%) developed spinal seeding metastases and was given spinal radiotherapy. In univariate analysis younger age vs older age: median 19.5 months vs 5.27 months (P = 0.0012); Karnofsky performance status ≥70 vs <70: median 15.3 months vs 2.67 months (P <0.0001), and external radiotherapy dose 60 Gy vs 66 Gy: median 11.6 months vs 3 months (P = 0.02) were found as significant prognostic factors for survival. In regression analysis a worse performance status (KPS <70) was found to be the only independent factor for survival (P = 0.014, 95% CI HR = 0.0043 [0.0001-0.15]). Conclusions Younger patients with primary glioblastoma multiforme had a relatively long survival (median, 19.5 months, with a 2-year survival rate of 30%) compared to older patients. This was due particularly to their better performance status.


Tumori | 2006

The value of postoperative radiotherapy in renal cell carcinoma: a single-institution experience.

H. Cüneyt Ulutin; Gorkem Aksu; Merdan Fayda; Okhan Kuzhan; Lutfu Tahmaz; Murat Beyzadeoglu

Aim To evaluate the efficacy of postoperative irradiation in renal cell carcinoma. Patients and methods Forty patients with localized renal cell carcinoma admitted to our hospital between 1986 and 1999 were evaluated. All patients were initially treated with radical nephrectomy. Postoperative radiotherapy was given to 26 of 40 patients (65%). Fourteen patients (35%) received no adjuvant therapy. Median age was 55 years (range, 20–70 years). Twenty-four patients (60%) were men and 16 patients (40%) were women. Histopathological diagnosis was renal cell carcinoma in all of the patients. N+ disease was present in 3 patients (7%). Stage I and II disease was present in 25 patients (63%) and stage III and IV disease in 15 patients (37%). Two patients (5%) had T1a disease, 11 patients (27%) had T1b, 15 patients (38%) had T2, 11 patients (27%) had T3a and 1 (3%) patient had T3b. In the radiotherapy group, renal bed and regional lymphatic fields were irradiated with daily fractions of 180–200 cGy/fraction to a total dose of 46–50 Gy, using parallel opposing fields. Results The 5-year overall survival rates were 70% in the postoperative radiotherapy group and 20% in the no adjuvant treatment group, showing no significant difference (P = 0.1). The 5-year disease-free survival rates were 66% in the radiotherapy group and 16% in the no treatment group, with a significant difference in both univariate and multivariate analyses (P = 0.045 and P = 0.0007, respectively). Stage III and IV disease, tumor size ≥7 cm, presence of distant metastasis and lactate dehydrogenase level >450 U/L were found to be adverse prognostic factors for overall survival in both univariate and multivariate analyses. Analyzing the factors affecting disease-free survival, absence of postoperative radiotherapy and tumor size ≥7 cm were found to be adverse prognostic factors in univariate and multivariate analyses. Conclusion Multi-institutional prospective randomized trials using modern radiotherapy techniques such as conformal radiotherapy and intensity-modulated radiotherapy are necessary to evaluate the real role of radiotherapy and its effect on survival in renal cell carcinoma, especially in selected patients with a high risk of local or regional failure.


Pediatric Hematology and Oncology | 2008

Posttraumatic stress disorder and risk factors in parents of children with a cancer diagnosis.

Irem Yalug; Funda Corapcioglu; Merdan Fayda; Gorkem Aksu; Eviç Zeynep Başar; Kıvanç Yaluğ; Tamer Aker

The purpose of this study was to determine the prevalence of posttraumatic stress disorder (PTSD) in parents of children with cancer. Five questionnaires were administered to 104 parents, including a sociodemographic questionnaire, a traumatic events check list, the Structured Clinical Interview for DSM-IV PTSD and Major Depressive Disorder modules, and the self-rating instrument General Health Questionnaire-12. The prevalence of PTSD was 34.6%. The statistically significant tendency to develop PTSD were found in the female gender, better educational status, death of a loved one, previous history of psychiatric disorder, having a child with poorer prognosis, and the presence of radiotherapy in childs treatment. The vulnerable parents must receive psychosocial support.


International Journal of Gastrointestinal Cancer | 2003

Colon cancer with isolated metastasis to the kidney at the time of initial diagnosis

Gorkem Aksu; Merdan Fayda; Burak Sakar; Yersu Kapran

Blood-borne metastases to the kidneys from solid tumors have received little attention in the medical literature because they usually occur in a setting of advanced systemic disease, and renal involvement is a elatively minor cause of symptoms. Although the frequency of metastases to the kidney in cancer patients is 7–13% in large autopsy series, incidental discovery of a renal metastasis as the first manifestation of a primary tumor is a very rare event. The most common primary malignancy to involve the kidney is bronchogenic carcinoma, followed by breast and gastrointestinal cancers. In this article, we report a patient with left colon cancer and isolated metastasis to the right kidney at the time of initial diagnosis. Left hemicolectomy and right nephrectomy were performed. Adjuvant systemic chemotherapy consisting of 5-fluorouracil (5-FU) and folinic acid (FA) was given. 5-FU and FA were stopped after four cycles because metastases to the lung and liver occurred about 3 mo after the surgery during adjuvant chemotherapy. Capecitabine was started. The patient died 9 mo after the discovery of the isolated renal metastasis. Nephrectomy is more for diagnostic clarification in the setting of synchronous primary because it has no effect on survival and its effect on quality of life is minimal; as seen in our case, the other organ metastases rapidly occur and the survival is limited. Nephrectomy may also compromise the choice of chemotherapy agents that require renal clearance, thus a careful evaluation of renal functions is necessary if a nephrectomy is performed. In the matter of a decreased renal clearance, the doses of these drugs should be decreased or the choice should be reevaluated.


Onkologie | 2010

The effect of tumor size on overall survival in patients with pT3 gastric cancer: experiences from 3 centers.

Ahmet Bilici; Kazim Uygun; Mesut Seker; Bala Basak Oven Ustaalioglu; Mehmet Aliustaoglu; Suleyman Temiz; Gorkem Aksu; Cem Gezen; Dilek Yavuzer; Serap Kaya; Taflan Salepci; Alpaslan Mayadagli; Mahmut Gumus

Background: Although a number of studies have investigated whether tumor diameter is a prognostic factor in gastric cancer, no consensus was reached on its clinical importance. In this study, we aimed to determine the effect of tumor size on survival in patients with pT3 gastric cancer. Patients and Methods: A total of 232 patients with pT3 gastric cancer, who underwent curative gastrectomy with D2 lymph node dissection, were retrospectively analyzed. Receiver operating characteristics analysis showed that the cutoff value for tumor size was 8 cm. On the basis of this cutoff point, patients were divided into 2 groups: small-size tumors (SST, ≤8 cm) and large-size tumors (LST, >8 cm). The prognostic significance of tumor size and the relationship between tumor size and other prognostic factors were evaluated. Results: LST was detected in 44% of patients. Resection type, tumor site, lymph node metastasis, tumor differentiation, lymphatic vessel invasion, and blood vessel invasion were correlated with tumor size. The median survival of patients with SST was significantly better than that of patients with LST (107 vs. 18.2 months; p < 0.001). Multivariate analysis indicated that tumor size was an independent prognostic factor (p = 0.001; hazard ratio (HR): 0.43) as were resection type and blood vessel invasion. Conclusions: Our results show that tumor size is an important prognostic indicator in patients with pT3 gastric cancer, who underwent curative gastrectomy, and that the rate of LST increased with aggressiveness and stage of disease. Tumor size may be a useful and reliable prognostic factor for detection and staging in patients with gastric cancer, who have a poor prognosis after curative resection.


Journal of Pediatric Hematology Oncology | 2014

Golden bullet-denosumab: early rapid response of metastatic giant cell tumor of the bone.

Ugur Demirsoy; Meriban Karadogan; Ozgur Selek; Yonca Anik; Gorkem Aksu; Bahar Muezzinoglu; Funda Corapcioglu

Giant cell tumor of the bone (GCTB) is usually a benign, locally aggressive tumor with metastatic potential. Histogenesis of GCTB is unknown and a correlation has not been found between histologic and clinical course. For this reason, many authors consider its prognosis unpredictable. Lung metastasis after GCTB treatment is well known and generally has unfavorable outcome, despite varied chemotherapy regimens. Denosumab, which inhibits RANK-RANKL interaction, is a new, promising actor among targeted therapeutic agents for GCTB. In this report, we emphasize on early rapid response to denosumab in metastatic GCTB.


Orthopedics | 2008

Spinal Cord Compression Due to Vertebral Hemangioma

Gorkem Aksu; Merdan Fayda; Mert Saynak; Ahmet Karadeniz

This article presents a case of multiple vertebral hemangiomas in a 58-year-old man with pain in the dorsal region and bilateral progressive foot numbness. Magnetic resonance imaging revealed multiple vertebral hemangiomas. One hemangioma at the T7 level demonstrated epidural extension, causing spinal cord compression. After treatment with radiotherapy, the patients symptoms improved significantly.


Radiation Oncology | 2014

Assessment of early and late dysphagia using videofluoroscopy and quality of life questionnaires in patients with head and neck cancer treated with radiation therapy

Eda Yirmibeşoğlu Erkal; Doğu Canoğlu; Ahmet Kaya; Gorkem Aksu; Binnaz Sarper; Gur Akansel; Tülay P. Meydanci; Haldun Şükrü Erkal

BackgorundThe aim of this study was to evaluate dysphagia in patients with head and neck cancer (HNC) undergoing three-dimensional conformal radiation therapy using objective and subjective tools simultaneously and to associate the clinical correlates of dysphagia with dosimetric parameters.MethodsTwenty patients were included in the study. The primary tumor and the involved lymph nodes (LN) were treated with 66-70 Gy, the uninvolved LN were treated with 46-50 Gy. Six swallowing structures were identified: the superior pharyngeal constrictor muscle (SPCM), the middle pharyngeal constrictor muscle (MPCM), the inferior pharyngeal constrictor muscle (IPCM), the base of tongue (BOT), the larynx and the proximal esophageal sphincter (PES). Dysphagia was evaluated using videofluoroscopy and European Organization for Research and Treatment of Cancer (EORTC) QoL questionnaire (QLQ-C30) and supplemental EORTC QoL module for HNC (QLQ-H&N35). The evaluations were performed before treatment, at 3 months and at 6 months following treatment.ResultsOn objective evaluation, the Dmax for the larynx and the sub-structures of the PCM were correlated with impaired lingual movement, BOT weakness and proximal esophageal stricture at 3 months, whereas the V65, the V70and the Dmax for the larynx was correlated with BOT weakness and the V65, the V70, the Dmax or the Dmean for the sub-structures of the PCM were correlated with impaired lingual movement, BOT weakness, reduced laryngeal elevation, reduced epiglottic inversion and aspiration at 6 months following treatment. On subjective evaluation, the V60, the Dmax and the Dmean for SPCM were correlated with QoL scores for HNSO at 3 months, whereas the V70 for SPCM were correlated with QoL scores for HNPA and the V60, the V65, the V70, the Dmax and the Dmean for SPCM were correlated with QoL scores for HNSO at 6 months following treatment.ConclusionsThe use of multiple dysphagia-related endpoints to complement eachother rather than to overlap with one another, as well as the use of multiple evaluations over time to represent a scale of early to late findings might provide a better insight in terms of the association of the clinical correlates of dysphagia with the dose-volume data for the dysphagia-related anatomical structures.

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Mahmut Gumus

Istanbul Medeniyet University

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