Aysegul Unuvar

NAD(P)H:quinone oxidoreductase 1 null genotype is not associated with pediatric de novo acute leukemia

NAD(P)H:quinone oxidoreductase1 (NQO1) is a two‐electron reductase that detoxifies quinones derived from the oxidation of phenolic metabolites of benzene. Exposure to benzene metabolites increases the risk of hematotoxicity and leukemia. NQO1 enzyme activity protects the cells against metabolites of benzene. C to T base substitution at nucleotide 609 of NQO1 cDNA (C609T) results in loss of enzyme activity. Low NQO1 activity may play a role in etiology of acute leukemia.

Respiratory syncytial virus infection outbreak among pediatric patients with oncologic diseases and/or BMT

Respiratory syncytial virus (RSV) has been reported to cause severe morbidity and mortality among cancer patients receiving chemotherapy with or without autologous/allogeneic hematopoetic stem cell transplantation (HSCT). There have been few reports describing the outcome of RSV infection specifically among pediatric oncology patients.

Secondary Hemophagocytic Lymphohistiocytosis Induced by Malaria Infection in a Child with Langerhans Cell Histiocytosis

Since the first description of infection-associated hemophagocytosis (IAHS), the list of precipitating infectious agents causing hemophagocytic syndrome has grown. A lymphohistiocytic proliferation with hemophagocytosis may develop as a result of macrophage activation, viral or bacterial infection, parasitic infestations, or malignancy. The authors report on a 3-year-old boy with Langerhans cell histiocytosis (LCH), who developed IAHS during malaria infection. Hemophagocytic syndromes may complicate the course of LCH and cause diagnostic problems. Malaria is one of many infections that can precipitate secondary hemophagocytic lymphohistiocytosis.

Mediastinal Masses In Children: Experience With 120 Cases

Primary mediastinal malignancies are rare tumors and can originate from any mediastinal organ or tissue such as thymic, neurogenic, lymphatic, germinal, or mesenchymal. The authors reviewed all cases of primary pediatric mediastinal masses diagnosed over a 25-year period to determine the pattern of presentation, the histology, and the outcome of the surgical treatment. In this study, 120 primary pediatric mediastinal mass cases diagnosed between 1985 and 2011 are retrospectively evaluated according to their age, sex, symptoms, anatomical location, surgical treatment, and histopathological evaluation. The median age of the patients was 5.8 years. There were 34 benign and 86 malign tumors. Thirty patients were asymptomatic. Common symptoms in the patients were cough, dyspnea, fatigue, fever, abdomen pain, back pain, and neurological symptoms. According to their origins, they were presented as neurogenic tumors (38.3%), lymphomas (18.3%), undifferentiated sarcomas (15%), germ cell tumors (7.5%), and the other tumors (22%) thymic pathologies, lymphangiomas, rhabdomyosarcomas, lipomas, hemangiomas, and Wilms’ tumor. Complete resection of the tumor was performed in 86 patients, partial resection of the tumor was the intervention in 11 patients. In 23 patients, biopsy was undertaken. Because of the high incidence of asymptomatic or nonspecific presentation such as the upper airway disease, the presentation of a mediastinal mass in children may be challenging. Neurogenic tumors or lymphomas are indicating surgery, if possible complete resection, for both benign and malignant conditions. Although surgery is the mainstay of therapy for most mediastinal tumors, an experienced multidisciplinary approach is necessary.

Is the MDR1 C3435T Polymorphism Responsible for Oral Mucositis in Children with Acute Lymphoblastic Leukemia

BACKGROUND AND AIM Although the functional consequences of MDR-1 polymorphisms have been the subject of numerous studies, to the best to our knowledge, associations with clinical side effects of anticancer drugs have yet to be assessed. Our aim was to clarify any role of the C3435T polymorphism of the MDR1 gene in oral mucositis and its relation with elevated reactive oxygen species (ROS) levels, in children with acute lymphoblastic leukemia (ALL). MATERIALS AND METHODS The distribution of the MDR-1 C3435T polymorphism in 47 patients with ALL was determined by RFLP and compared with that of 68 healthy controls. RESULTS There were no association in distribution of genotypes of MDR-1 C3435T polymorphism and the risk of ALL. Oral mucositis were detected in 78.7% (n=37) of the patients and significantly related to the MDR-1 CT genotype (p=0.042), as confirmed by logistic regression analysis. CONCLUSION Our preliminary data suggest that children carrying the CT genotype are more prone to develop oral mucositis, which might mean that the heterozygous genotype leads to accumulation of more reactive oxygen species. Since a limited number of patients was investigated, further studies are needed to confirm these findings.

Allogeneic versus autologous versus peripheral stem cell transplantation in CR1 pediatric AML patients: a single center experience.

Treatment of childhood acute myelocytic leukemia (AML) in first remission, is still evolving. Allogeneic bone marrow transplantation (BMT) in patients with a donor has been well established, but the role of autologous transplantation remains of interest, particularly in the light of some encouraging results in adults.

LI-FRAUMENI SYNDROME IN A TURKISH FAMILY

Li-Fraumeni syndrome (LFS) is one of the familial cancers characterized by different tumors and hereditary TP53 mutations. The adrenocortical carcinoma (ACC) association with acute leukemia is unusual in childhood, even in LFS. The authors here present a family with pR337P mutation in TP53 gene who had a child with acute lymphoblastic leukemia (ALL) and associated adrenocortical carcinoma as a case 1 and his cousin with brain tumor as a case 2. A hereditary TP53 mutation supported the diagnosis of LFS in this family. The patients had many difficulties in treatment strategies and succumbed to death. The availability of a reliable molecular marker to detect the R337P TP53 mutation allows the rapid identification of carriers in families that have a child with ACC. Once identified, carriers could be screened for early detection of ACC by imaging and endocrine studies and should be given psychological support to prevent anxiety for death. Whether early detection of ACC will reduce the mortality in these patients remains to be determined.

SET oncogene is upregulated in pediatric acute lymphoblastic leukemia

AIMS AND BACKGROUND The SET gene is a target of chromosomal translocations in acute leukemia and encodes a widely expressed multifunctional phosphoprotein. It has been shown that SET is upregulated in BCR-ABL1-positive cell lines, patient-derived chronic myeloid leukemia CD34-positive cells, and some solid tumors. METHODS AND STUDY DESIGN We determined the expression level of SET in 59 pediatric acute lymphoblastic leukemia patients who were BCR-ABL-negative using quantitative real-time reverse-transcriptase-polymerase chain reaction. Results. We showed that SET expression was significantly upregulated in 96.5% of B-acute lymphoblastic leukemia (28 of 29; 16.6 fold) and 93% of T-acute lymphoblastic leukemia (28 of 30; 47.6 fold) patients. This upregulation was not associated with any clinical features or overall and relapse-free survival. CONCLUSIONS Our results showed that SET is significantly overexpressed in pediatric acute lymphoblastic leukemia samples, and an increased level of SET might contribute to leukemic process.

Human herpes virus type 8-associated Kaposi sarcoma in a pediatric liver transplant recipient

Çeltik C, Ünüvar A, Aydoğan A, Gökçe S, Öztürk G, Güllüoğlu M, Yılmaz G, Türkoğlu S, Anak S, Sökücü S, Durmaz Ö. Human herpes virus type 8‐associated Kaposi sarcoma in a pediatric liver transplant recipient.
Pediatr Transplantation 2011: 15: E100–E104.

How to manage an unresectable or recurrent sialoblastoma.

Only 2–5% of all salivary gland tumors occur in children. Sialoblastoma is an extremely rare salivary gland tumor diagnosed at birth or shortly thereafter with significant variability in histological range and clinical course, so that it may be difficult to predict the most appropriate therapy. In cases where surgical removal is not curative or technically feasible, chemotherapy may be attempted. We report herein a patient with progression of a huge partially resected sialoblastoma who was successfully treated with chemotherapy. Systemic chemotherapy with vincristine, actinomycin D, and cyclophosphamide (VAC) seems to be an effective adjuvant or neoadjuvant treatment option for unresectable or recurrent sialoblastoma. Pediatr Blood Cancer. 2010;55:374–376.