Omer Görgün

Onkoloji Enstitüsü, İstanbul, İstanbul, Istanbul, Turkey

Are you Omer Görgün?

Claim your profile

Publications (14)16.59 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Neuroblastoma (NBL), a malignant embryonic tumor derived from neural crest cells, is the most common tumor worldwide among children less than 1 year of age. Metastasis to the mandible is uncommon. This article reports the case of a 15-month-old male diagnosed with NBL with bone metastasis including the mandible which resulted in severe tooth mobility. Dentists or pediatricians should consider the primary or metastatic tumors of the maxillofacial region in the differential diagnosis in children presenting with premature loss of teeth related to tooth mobility.
    The Journal of clinical pediatric dentistry 01/2011; 36(2):203-6. · 0.34 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hypertrophic osteoarthropathy (HOA) is a syndrome characterized by clubbing of the fingers and toes, periosteal new bone formation of the long bones and polyarthritis. In this report, two children with intrathoracic Hodgkin's disease and HOA are presented. Intrathoracic neoplasms are one of the major causes of HOA in adults; however HOA is rarely associated with intrathoracic malignancies in children. HOA associated with intrathoracic Hodgkin's disease is even more rare, but should be kept in mind.
    Leukemia Research 08/2006; 30(7):899-902. · 2.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Variation in serum levels of CD44, which acts as an adhesion receptor involved in lymphocyte migration and binding, have been reported in some malignancies. The aim of this study is to compare serum levels of CD44 in children with sarcomas with those in healthy children. CD44 levels were measured by enzyme-linked immunosorbent assay (ELISA) in serum samples taken at diagnosis from 55 children with sarcomas and from 27 healthy children of similar age, sex, and socioeconomic status. There was no statistically significant difference between CD44 serum levels of children with sarcomas and those of healthy children. No significant difference was observed between CD44 serum levels of each patient group and those of control group (P > 0.05). There was no significant difference among CD44 serum levels of patient groups according to stage or outcome. In this study, serum CD44 levels were not found to be of value in the diagnosis or prognosis in children with sarcomas.
    Pediatric Blood & Cancer 02/2006; 46(1):62-5. · 2.56 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Brain is a rare site of metastasis in most extracranial pediatric solid tumors. The aim of this study is to investigate the incidence, treatment, prognosis of brain metastasis in extracranial pediatric malignant tumors in a single institution and to review the literature. From September 1989 to December 2002, 1100 children <or=16 years of age with extracranial solid tumors including lymphomas were diagnosed and treated in the Division of Pediatric Oncology, Oncology Institute, Istanbul University. Patients with parenchymal metastases in the brain were assessed. Sixteen (10 female, 6 male) of 1100 patients (1.45%) with extracranial solid tumors developed brain metastases. The median age of the patients was 10.5 (1-16) years. The diagnosis was sarcomas in 12 patients: 5 osteosarcomas, 4 Ewing's sarcoma family tumors, 1 rhabdomyosarcoma, 1 clear cell sarcoma of the soft tissue, 1 alveolar soft part sarcoma. Two patients had Wilms' tumor and two had germ cell tumors. Four patients (25%) had brain metastasis at diagnosis. Twelve (75%) developed brain metastasis during therapy or relapse at a median duration of 16 (1-70) months from initial diagnosis. All patients had metastases to various sites, mostly lung, at the time the brain metastases were detected. Treatment included surgery, followed by postoperative radiotherapy (RT) and chemotherapy (CT) in 1, S and RT in 1, S in 1, RT and CT in 6, RT in 1, CT in 1 and no treatment in 5. Only one patient with alveolar soft part sarcoma is alive with disease 20 months from diagnosis of brain metastasis. All other patients died at a median time of 2 months (2 days-6 months) from the time of brain metastasis. Children with metastatic cancer who develop headaches or any other neurologic symptom should be investigated for possible brain metastasis. Although, the outcome for these patients is dismal in this series and in the literature; reports of long term survival in a few cases with Wilms' tumor, osteosarcoma and alveolar soft part sarcoma who had isolated brain metastasis, suggest that a subset of patients may benefit from therapy.
    Journal of Neuro-Oncology 01/2005; 71(1):43-8. · 2.79 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hepatoblastoma is the most common primary liver tumour in children. Complete surgical removal is the treatment of choice for cure; however, in most cases the tumour is unresectable because of its extensive hepatic involvement. Nineteen pediatric cases (11 boys, 8 girls) with ages ranging from three months to 17 years were referred for management to our clinic from 1982 until 2000. All but three suffered from abdominal distention. The other frequent complaints were abdominal mass, anorexia, fatigue, abdominal pain and fever. Physical examination revealed enlarged liver in all patients. In addition to laboratory studies, they were pre-operatively examined by ultrasonography and, in recent cases, computed tomography was also used. Serum alpha-fetoprotein levels were found to be elevated in all patients. In thirteen cases, hepatic resections (10 lobectomies, 2 trisegmentectomies, 1 segmentectomy) were performed. In six children only liver biopsies could be done because of the huge tumour size. However, in three of them the tumours were excised at the second laparotomy, but only one patient survived. All of the patients - except two who were lost in the early postoperative period - received chemotherapy whether the tumour was excised or biopsied. In this series the mortality rate was found to be very high (91%) in the 1980s, and more reasonable (50%) in the 1990s, with an overall mortality rate of 73 per cent. This result might be explained with late referral and advanced stage at diagnosis. In addition, we speculate that a combination of improved chemotherapy and technical advances in anesthesia and hepatic resection caused the obvious differences in the survival rates between the two periods.
    Acta chirurgica Belgica 07/2004; 104(3):318-21. · 0.44 Impact Factor
  • Rejin Kebudi, Omer Görgün, Inci Ayan
    [Show abstract] [Hide abstract]
    ABSTRACT: Etoposide (VP-16) is a topoisomerase II inhibitor that is effective in a broad spectrum of pediatric and adult malignancies. Chronic, low-dose, oral VP-16 has also been shown to be active in some recurrent malignancies mostly in adults. The aim of this prospective, single institution study is to assess the efficacy and toxicity of oral VP-16 in children with progressive or recurrent (P/R) sarcomas. Twenty-one children (10 girls and 11 boys) with R/P sarcomas and a median age of 11 years (range 3-16 years) were enrolled in this study. The diagnosis was Ewing sarcoma family tumor (ESFT) in seven, osteosarcoma in eight, rhabdomyosarcoma in four, clear cell sarcoma of soft tissue in one, fibrosarcoma in one patient. Oral VP-16 was administered at a dose of 50 mg/m(2)/daily for 20 days. The next course was initiated after a 10 day rest. Response to oral VP-16 was assessed after two courses. There was an objective response (one complete response [CR], two partial responses [PR]) in three patients (14%) by two courses of oral VP-16 alone. One of these patients with PR achieved CR by the use of radiotherapy (RT) and further oral VP-16. Two more patients (9.5%) achieved CR by RT and oral VP-16. Eight (38%) patients had disease stabilization for 2-15 months. Two patients (9.5%) are long-term survivors. They are alive with no evidence of disease (NED) 79 and 94 months from time of relapse/progressive disease (PD). A patient developed acute myeloid leukemia and died. There was no major acute toxicity related to oral VP-16 in a total of 126 courses. Oral VP-16 therapy is simple, relatively nontoxic, and does not necessitate hospitalization. The cure rate is small. Given the risk of second malignancy, especially in children with previous exposure to topoisomerase II inhibitors and alkylating agents, this regimen may be used as a palliative treatment or in patients with poor prognosis.
    Pediatric Blood & Cancer 05/2004; 42(4):320-4. · 2.56 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The role of surgery in intraabdominal Burkitt's lymphoma remains controversial and different opinions are present in the literature. In our institution, forty patients (30 boys and 10 girls) with intraabdominal Burkitt's lymphoma with ages ranging from 3 to 12 years have been treated and followed from 1989 through 2000. In ten cases, the patients underwent surgery because of their acute abdominal diseases (intestinal obstruction in 5, intussusception in 3, intestinal perforation in one, and acute appendicitis in one). The remaining thirty patients were referred to our clinic because of their abdominal masses, pain, anorexia and fatigue. Twelve children had localized tumors and total resection could be performed. There was one death in this group due to central nervous system involvement during chemotherapy. In the remaining 28 children, extensive intraabdominal diseases were detected. In four of them, debulking procedures were performed, while in 24 children only biopsies could be made; 8 of them underwent a second-look operation. In the debulking procedures group, two children were lost (50 %) due to tumorlysis and acute renal failure. In the biopsy group, there were six deaths (25 %). All patients received chemotherapy after operative recovery. In conclusion, our results suggest that when the tumor is localized, total resection results in a good outcome. However, in the presence of extensive intraabdominal diseases instead of resection, the operation should be limited to biopsy only.
    European Journal of Pediatric Surgery 09/2003; 13(4):236-9. · 0.98 Impact Factor
  • Medical and Pediatric Oncology 05/2003; 40(4):256-7.
  • Medical and Pediatric Oncology 07/2002; 38(6):455-6.
  • [Show abstract] [Hide abstract]
    ABSTRACT: With the availability of new broad-spectrum antibiotics, initial therapy with a single agent has become an alternative to classic combinations, especially beta-lactam antibiotics plus aminoglycosides, in the management of febrile neutropenic cancer patients. Since January 1994, monotherapy has been used for empiric initial treatment at our center. The aim of this prospective randomized study is to compare the efficacy of cefepime (CFP), a new fourth-generation cephalosporin, and ceftazidime (CFZ) as empirical monotherapy of febrile neutropenic patients with solid tumors. From January 1998 to November 1998, 63 episodes of fever and neutropenia occurring in 33 children with solid tumors including lymphomas, were randomized to receive treatment with either CFP or CFZ. The patients were analyzed for leukocyte count and absolute neutrophil count (ANC) at entry, days in fever, neutropenia and hospitalization, and side effects of drugs. Success with or without modifications of the initial antibiotic was defined as survival through neutropenia; failure was death due to infection. In our study group, with a median age of 7 [(1/12)-14] years, CFP was administered in 32, and CFZ in 31 episodes. An infection was documented microbiologically in eight episodes (25%) in the CFP arm and in nine episodes (29%) in the CFZ arm. The success rate with initial empiric monotherapy was 62.5% in the CFP arm and 61.3% in the CFZ arm respectively (P > 0.05). The total success rate (success with or without modification) was 100% in both arms. No major adverse effects were observed in either groups. CFP is as effective and safe as CFZ for the empirical treatment of febrile episodes in neutropenic patients with solid tumors.
    Medical and Pediatric Oncology 04/2001; 36(4):434-41.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Children with cancer receiving intensive chemotherapy require multiple transfusions and are at increased risk for blood transmittable diseases such as hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infections. Sera from 50 children (24 female, 26 male) admitted between January, 1994, and December, 1995, with solid tumors receiving intensive chemotherapy and multiple transfusions were investigated for HBsAg, anti-HBs, anti-HBc, anti-HCV, and anti-HIV by ELISA at diagnosis and at the end of therapy. HBsAg, HBV, HCV, and HIV seropositivities were 0%, 4%, 2% and 0% at diagnosis and 10%, 20%, 14% and 0% at the end of therapy, respectively. The high seroprevalence of HCV may be due to the lack of anti-HCV screening of blood products in the blood banks during the study period. Although the HBV seroprevalance of 20% found in this study is much lower than the value of 56% found in a previous study conducted during 1986-1989 in a similar patient population and a similar setting, it is still high. Children infected with HBV during immunosuppressive therapy are at greater risk of becoming chronic carriers and precautions must be taken for immunization of these children.
    Medical and Pediatric Oncology 03/2000; 34(2):102-5.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Hypertrophic osteoarthropathy (HOA), well known in adults, is rarely encountered in children. The clinical features include clubbing of the fingers and toes, arthritis, and painful periosteal new bone formation of the tubular bones. The association of malignant disorders with HOA is more common in adults than in children. In this paper, a 12-year-old boy with intrathoracic Hodgkin disease and HOA is presented and four other children with HOA and Hodgkin disease in the literature reviewed. The presence of HOA has been thought to be a bad prognostic sign, but complete remission of Hodgkin disease and regression of clinical signs and symptoms of HOA were attained in our patient after chemotherapy and radiotherapy, and continue during 9 months post-therapy follow-up. HOA accompanying a malignant tumor in children is very rare. Only 5 cases have been associated with Hodgkin disease, including the present boy. It is important that patients with symptoms of HOA and an intrathoracic mass be examined carefully to rule out a malignancy.
    Medical and Pediatric Oncology 01/1998; 29(6):578-81.
  • [Show abstract] [Hide abstract]
    ABSTRACT: With the increasing use of ifosfamide in pediatric tumors, nephrotoxicity became the point of interest since it may cause chronic morbidity. In this study, the renal glomerular and tubular functions of 25 cases with solid tumors aged between 2-17 years (median 9) who were treated with ifosfamide, were investigated. For this purpose, routine blood urea, creatinine, calcium, phosphorus, electrolytes, urinary creatinine, phosphorus, glucose, protein and urinary retinol binding protein as well as microglobulin were evaluated. Except for two patients who had hypophosphatemia, phosphaturia, and proteinuria, all the cases had normal blood biochemistry, creatinine clearance, tubular phosphate reabsorption; and none had proteinuria, hematuria, or glycosuria. In spite of these findings, urine beta 2 microglobulin and retinol binding protein were found to be high in 11 patients and this elevation persisted during the following one year in 8 cases whose treatments were stopped and their levels increased in three patients who continued to receive fosfamide therapy. In correlation with the increasing cumulative dose of ifosfamide (32-126 g/m2), urinary retinol binding protein or beta 2 microglobulin of patients who are treated with ifosfamide may predict the existence of renal toxicity even if other routine renal function tests are normal. Thus, the periodic evaluation of urinary beta 2 microglobulin and retinol binding protein in patients receiving chemotherapy containing ifosfamide is recommended.
    Journal of experimental & clinical cancer research: CR 07/1997; 16(2):227-30. · 3.27 Impact Factor
  • I Ayan, R Kebudi, S Doğan, G Tokuç, Ö. Görgün
    [Show abstract] [Hide abstract]
    ABSTRACT: Granulocyte colony-stimulating factor (G-CSF) has been used to reduce the duration and/or degree of neutropenia of different etiologies in recent years. In this study, experience with the use of G-CSF (Neupogen, Roche) after 123 courses of highly myelosuppressive chemotherapy administered to 31 (20 female, 11 male) patients with pediatric solid tumors is reported. G-CSF was initiated at a white blood cell (WBC) count of 918 +/- 452/microL (100-2000), at a dose of 7.6 +/- 2.3 micrograms/kg/d (5-14) subcutaneously for 5.2 +/- 2.4 days (2-18). G-CSF was given for afebrile neutropenia after 82 and for febrile neutropenia after 41 courses. Only in two episodes where G-CSF was given for afebrile neutropenia, fever developed. The average hospitalization period for febrile neutropenia was 9.8 +/- 3.3 days (5-20). Chemotherapy could be given on scheduled time and dosage in 90% of the courses in which G-CSF was used for afebrile neutropenia. G-CSF was well tolerated. Bone pain was observed in two patients and urticaria in one patient. In conclusion, G-CSF increased the WBC count effectively, there were only two febrile episodes in 82 courses in children receiving G-CSF for afebrile neutropenia, it was well tolerated, and it was found to be feasible for use in a developing country.
    Pediatric Hematology and Oncology 01/1996; 13(5):417-24. · 0.96 Impact Factor