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Biomedical subjects

Bilgehan Yalçin

Publications and source records attributed to Bilgehan Yalçin.

At least 19 recordsLinked to original sources

Astrocytic tumors in children: treatment results from a single institution.

OBJECTIVE: The aims of this study are to evaluate the patients with astrocytomas and to investigate survival rates and prognosis. PATIENTS AND METHODS: Five hundred fourteen patients diagnosed with brain tumor between 1972 and 2003 were retrospectively analyzed. Three different chemotherapy regimens were used according to years. CCNU-based protocols were used in the early years; COPP (cyclophosphamide, oncovin, procarbazine, prednisolone) and CDDP+VP16 (cisplatinum + etoposide) were the other protocols used in the following years. Radiotherapy was used after 3 years of age according to protocols. RESULTS: Ninety-eight (19%) out of 514 patients have astrocytic histopathology. The histopathologic distribution was as follows: low grade, 55 patients; high grade, 43 patients. COPP regimen was given to 24 patients, CCNU-based regimen to 13, and CDDP+VP16 to 10 patients. We did not use any chemotherapy in 51 patients. Overall survival (OS) and event free-survival rates were 59.2 and 45.7% in whole group. OS rates were 93.3 and 22.4% for low-grade and high-grade histopathology, respectively (p=0.0001). OS for CCNU, CDDP+VP16, and COPP were 35.9, 22.8, and 30.4%, respectively. CONCLUSION: Low-grade astrocytomas are highly responsive to the surgery, and they do not need any further treatment unless the patient has relapse or recurrence. Still, the treatment of the high-grade tumors is a problem, and it needs new treatment approaches.

Adolescent↗

Treatment results of 84 patients with nasopharyngeal carcinoma in childhood.

BACKGROUND: To evaluate the clinical characteristics, treatment regimens, survival, and late complications in patients with nasopharyngeal carcinoma. PROCEDURE: Eighty-four patients diagnosed with nasopharyngeal carcinoma between 1972 and 2002 were retrospectively evaluated. Tumor status, lymph node involvement, metastasis, and stage were assessed according to the TNM classification. All patients were treated with radiotherapy and chemotherapy. Chemotherapeutic regimens involved cyclophosphamide from 1972 to 1982, vincristine + cyclophosphamide + epirubicine and actinomycin-D protocol from 1982 to 1999 and cisplatin + methotrexate + 5-fluorouracil with leucovorine rescue after 1999. Mean and median values were used for the demographic characteristics. Kaplan-Meier survival curves were used for survival analysis. The patient groups were compared in terms of survival duration using a log-rank test. RESULTS: There were 51 males and 33 females with a median age of 13 years (7-17) at diagnosis. At the time of diagnosis, 78.5% of the patients were at advanced stage (stages III and IV). Overall and event-free survival rates were 56.3% and 50.1%, respectively. Survival was inversely affected by advanced nodal status (P = 0.01). The survival rates (80%) were found higher with cisplatin + methotrexate + 5-fluorouracil + leucovorine rescue regimen. The most frequent late complications after therapy were hypothyroidism (9.5%), dental caries (7.1%), and trismus (7.1%). CONCLUSION: The cisplatin-based regimen was the best chemotherapeutic regimen. Less toxic regimens with better survival rates should be investigated in patients with nasopharyngeal carcinoma.

Adolescent↗

Paratesticular metastasis from Wilms tumor associated with a hydrocele.

Metastatic sites other than the lungs, lymph nodes, and liver are unusual for Wilms tumor (WT). Intra-scrotal metastasis is very rare. We report a 3-year-old boy with stage IIA WT, who experienced paratesticular metastasis 2 months after surgery for an abdominal recurrence. He had right scrotal hydrocele at initial diagnosis. The patient underwent right radical orchiectomy, and pathological examination revealed paratesticular WT metastasis. Intra-abdominal and peritoneal disseminated metastases followed. We considered that tumor cells spread through the patent processus vaginalis and grew at paratesticular space in hydrocele. One month after the end of 12 months of salvage chemotherapy and abdominal radiotherapy, the patient has no evidence of disease.

Child, Preschool↗

Immunogenicity of hepatitis a vaccine in children with cancer.

This study evaluated the immuned response of the hepatitis A vaccine in children with cancer who were receiving chemotherapy. Twenty-eight patients with lymphomas or solid tumors and who had negative serology for hepatitis A were enrolled. The median age was 4.7 years (range 2-16). The patients received 1440 IU hepatitis A vaccine at 0 and 6 months. Seroconversion rates at the first and seventh months were 60% (n = 17/28 patients) and 89% (n = 24/27 patients). No adverse effects were observed. The hepatitis A vaccine was found to be effective and safe in children with cancer.

Adolescent↗

Infantile hepatic hemangioendothelioma with elevated serum alpha-fetoprotein.

Infantile hemangioendothelioma is the most common hepatic vascular tumor in infants less than 6 months of age, with a prevalence of 1%. Serum alpha-fetoprotein levels have been used as an important tumor marker for hepatoblastoma, hepatocellular carcinoma, and germ cell tumors. It is rarely elevated in hepatic hemangioendothelioma. The authors report an infant with a hepatic hemangioendothelioma associated with elevation of serum alpha-fetoprotein who was treated with corticosteroids. In young infants, a solitary hepatic mass and elevated serum AFP level may not always be associated with hepatoblastoma. Infantile hemangioendothelioma must be differentiated by MRI or other radiological techniques before performing invasive procedures.

Age Factors↗

Second neoplasms in pediatric patients treated for cancer: a center's 30-year experience.

To investigate the incidence and outcome of secondary neoplasms in pediatric patients treated for childhood cancer. Between December 1971 and January 2000, a total of 5859 patients younger than age 17 were diagnosed and treated for childhood cancers in our center. Of this group, 1511 (36%) patients were followed for more than 36 months. These long-term survivors were included in this analysis. Twenty-six patients developed a secondary malignancy with an overall risk of 1.7% in this cohort. The male:female ratio was 17:10, with a median age of 7.66 at diagnosis (range, 2 to 16 y). Four patients (14.8%) with Hodgkin lymphoma; 3 each (11.1%) with retinoblastoma and rhabdomyosarcoma; 2 each (7.4%) with Wilms tumor, Ewing sarcoma, medulloblastoma, ganglioneuroblastoma, and non-Hodgkin lymphoma; and 1 each (3.7%) with ependymoma, nasopharyngeal carcinoma, osteosarcoma, astrocytoma had a secondary malignant disease during the long-term follow-up period. Secondary malignant diseases were osteosarcoma in 6 patients, acute lymphoblastic leukemia in 2, acute myelogenous leukemia in 2, and rare malignant disease in others. Four patients with osteosarcoma developed disease within the radiation field. Osteosarcoma was the most frequently occurring secondary neoplasm. Less toxic treatment modalities should be used to decrease the risk of secondary malignant diseases.

Adolescent↗

Central nervous system tumors in patients under three years of age: treatment results of a single institute.

Eighty-six patients under 3 years of age with central nervous system tumors were retrospectively analyzed between 1972 and 2003. Surgical resection was done in all patients except for those with optic glioma, pons glioma and pineal tumor. Three different chemotherapy regimens were used in different time periods. In 48 patients, the tumor was located in the posterior fossa, and 29 patients had a supratentorial tumor. We had 32 (37.2%) patients with embryonic tumors (21 medulloblastoma, 4 ependymoblastoma, 5 with atypical teratoid rhabdoid and 2 with supratentorial primitive neuroectodermal tumors), 21 (24.4%) with ependymoma, 14 (16.3%) with optic glioma, 10 (11.6%) with astrocytoma, 3 (3.5%) with pons glioma and 6 (7.0%) with others. Overall (OS) and event-free survival rates were 49.5 and 40.9%. OS rates according to the tumor localizations were 40.9 and 68.1% in the posterior fossa and supratentorial localizations, respectively (p=0.001). OS rates were 33.7, 41.3 and 88.8% for the medulloblastoma+primitive neuroectodermal tumor groups, ependymoma and astrocytoma, respectively (p=0.0001). Most of the patients had primitive embryonic tumors (37.2%). The best prognostic factors were tumor localization and histology.

Antineoplastic Combined Chemotherapy Protocols↗

Renal involvement of non-Hodgkin's lymphoma and its prognostic effect in childhood.

OBJECTIVE: To evaluate renal involvement in childhood lymphoma and define its prognostic effects. PATIENTS AND METHODS: One hundred and four patients with non-Hodgkin's lymphoma and renal involvement on admission to a single center between 1972 and 2003 were evaluated retrospectively. Blood urea nitrogen, serum creatinine, uric acid, electrolytes, and lactate dehydrogenase levels, as well as urinalysis, were evaluated. One or more of the following imaging methods were performed: intravenous urogram, ultrasound, computed tomography, and magnetic resonance imaging. The chi2 test was used to compare the groups. The Kaplan-Meier survival method was used to calculate survival rates, and the log-rank test was used to compare groups with respect to survival. Survival rates were also compared in two different time periods (before 1991 and after 1991). RESULTS: There were 76 boys and 28 girls with a median age of 6 (0.9-16) years. The renal infiltration pattern was nodular in 62 patients (59.6%) and diffuse in 40 patients (38.5%). Two patients had tumoral masses that originated from their kidneys (1.9%). Renal involvement was bilateral in 75 patients (72.1%); the remaining 29 patients had unilateral involvement. The overall survival rate was 42.5% with a median follow-up of 64 months. The factors that had a statistically significant impact on survival were high creatinine (p = 0.00001) and blood urea nitrogen levels (p = 0.0001), the onset of tumor lysis syndrome (p = 0.01), and the need for dialysis (p = 0.009). The survival rate was higher in the time period after 1991 (p = 0.01). CONCLUSION: Impaired renal function is a poor prognostic factor for non-Hodgkin's lymphoma. Renal function should therefore be monitored closely. Renal dysfunction caused by direct tumoral involvement may complicate therapy and shorten survival.

Adolescent↗

Evaluation of thrombotic children with malignancy.

The purpose of this study was to evaluate inherited and acquired prothrombotic risk factors among children with malignancies who have thrombosis and emphasize the importance of inherited prothrombotic risk factors. Thirty-seven consecutive children with thrombosis and malignancy were included in this study. The patients were evaluated separately for time of development of thrombosis, insertion of a central venous line (CVL), history of L: -asparaginase usage, and recent infections. Prothrombotic risk factors such as factor V G1691A and prothrombin G20210A mutation, protein C, protein S, antithrombin III deficiencies, factor VIII and lipoprotein(a) elevation, and antiphospholipid antibodies were analyzed for all patients. Of 387 children with thrombosis, 37 (9.5%) had a malignancy. Thrombosis was detected in 9 patients at the time of diagnosis, during maintenance therapy in 25 patients, and after the discontinuation of treatment in 3 patients. One or two additional prothrombotic risk factors other than L: -asparaginase therapy and insertion of central venous lines were present in 20 of these patients (54%). It was found that eight patients had the factor V G1691A mutation in the heterozygote state. One of them had the factor V G1691A mutation associated with a history of infection and one patient had the factor V G1691A mutation associated with factor VIII elevation. One had the the prothrombin G20210A mutation in the heterozygote state, four had lipoprotein(a) elevation, two had factor VIII elevation, one had a decreased protein S level, one had a decreased protein C level, one had antiphospholipid positivity, and two had histories of infection. Malignancy is an important risk factor for the development of childhood thrombosis. However, the risk of thrombosis increases when accompanied by additional prothrombotic risk factors. For this reason, especially children with malignancy and at high risk for the development of thrombosis, such as those who have received L: -asparaginase or a replaced CVL during their therapy, might be screened for additional prothrombotic risk factors and appropriate measures might be taken to prevent the development of thrombosis.

Activated Protein C Resistance↗

Discitis following lumbar puncture in non-Hodgkin lymphoma.

Discitis in children is a rare disorder of intervertebral disc and vertebral end plate. Infection or trauma, like lumbar puncture, may be the possible causes. Low-back pain and gait disturbance are the main symptoms. The most appropriate diagnostic procedure is MRI. Treatment is mainly empirical. Here a case with non-Hodgkin lymphoma is discussed. Treatment consisted of strict bed rest and antibiotics. Safe and sterile technique is important in patients with invasive procedures like intrathecal chemotherapy. Although discitis is a self-healing condition, it might cause vertebral osteomyelitis. In this regard, physicians should be aware of this probable complication after lumbar puncture and manage it earlier in children with cancer.

Adolescent↗

Primary testicular Burkitt lymphoma in a child.

A 13-year-old boy was referred to the authors' hospital following a right inguinal orchiectomy for a right scrotal mass. Histopathological examination revealed Burkitt lymphoma. The left testis was found to be small with heterogeneous parenchyma by scrotal ultrasound (US) and other systemic investigations were negative for lymphoma involvement. Ultrasound-guided fine-needle aspiration biopsy showed no evidence of involvement in the left testis. Considering stage I Burkitt lymphoma, chemotherapy was started. Following the first course, US findings changed: the volume of the left testis decreased and the parenchyma became homogeneous. The left testis was considered to be involved by lymphoma at initial diagnosis and chemotherapy was intensified. At the end of 5 months of chemotherapy the left testis was again heterogeneous in US. A wedge-biopsy was negative for lymphoma. The patient is under regular follow-up and is in complete remission 19 months after the end of chemotherapy. Primary testicular lymphoma is quite rare in children and experience is limited. Changes in testicular size and parenchyma by US should not necessarily indicate involvement by lymphoma in pubertal boys.

Adolescent↗

Primary malignant skin tumors in children: etiology, treatment and prognosis.

OBJECTIVE: The aim of the study was to evaluate the etiology, treatment and prognosis of the malignant skin tumors in children. METHODS: Twenty-one patients who had been diagnosed with malignant skin tumors between 1972 and 2003 were retrospectively analyzed. Age range was 0.5-20 years (median 9), and the male/female ratio was 12/9. We had nine (42.9%) patients with malignant melanoma, five (23.8%) with primary skin non-Hodgkin lymphoma, three (14.3%) with Kaposi sarcoma (KS), two (9.5%) with basal cell carcinoma (BCC), and two (9.5%) with squamous cell carcinoma (SCC). RESULTS: We could define the etiologic factors in only nine (42.9%) patients. Two KS cases were associated with renal transplantation, two cases of malignant melanoma occurred within the area of giant hairy cell nevus, one melanoma patient previously had bone marrow transplantation due to Gricelli syndrome, one patient with BCC had xeroderma pigmentosum and the other BCC had got radiotherapy due to previous diagnosis of medulloblastoma. One SCC patient also had xeroderma pigmentosum and the other had previous skin burn. Overall survival rate was 77%. Melanoma patients were treated successfully with high-dose interferon. CONCLUSION: Although malignant skin tumors are rare in childhood, the prognosis is relatively better than it is for adults. Malignant melanoma was the most frequent tumor. Forty-three per cent of our patients had an underlying defect in their immune barriers which is thought to be responsible for the development of their malignancies.

Adolescent↗

Leptin and neuropeptide Y plasma levels in children with cancer.

This study investigated leptin and neuropeptide Y levels in children with cancer, the relationship of those levels to cachexia, and their usefulness as prognostic indicators. Twenty-three newly diagnosed children with cancer were included in the study. The median age at diagnosis was 8 years (range 1.5-14), and the male to female ratio was 13:10. Body mass index, serum leptin and neuropeptide Y levels were measured at diagnosis and at each cycle of chemotherapy. The mean neuropeptide Y level was 211.1 pmol/l at diagnosis and decreased to 92.8 pmol/l at the fifth cycle of chemotherapy. In contrast, the mean leptin level was 3.9 ng/ml at diagnosis and increased to 13.0 ng/ml at the fifth cycle of chemotherapy. Thus, levels of these factors are influenced by treatment status and disease progression. The mean neuropeptide Y level at diagnosis was 82.32 pmol/l in children with complete remission and 430.16 pmol/l in those who died with disease during the follow-up period. The mean leptin level at diagnosis was 6.60 ng/ml in children with complete remission and 0.192 ng/ml in patients who died with disease during the follow-up period. The neuropeptide Y and leptin levels seem to be related to prognosis and could be used as prognostic indicators in the follow-up of children with cancer.

Adolescent↗

An unusual cause of acute renal failure: renal lymphoma.

Renal involvement is a common finding in non-Hodgkin's lymphoma (NHL). Acute renal failure at initial presentation due to lymphomatous infiltration of the kidneys has been described infrequently. We report a 17-year-old male who presented with acute renal failure due to massive lymphomatous infiltration of the kidneys, which necessitated hemodialysis. The diagnosis of B-cell NHL was established by tru-cut biopsy of the kidneys and the patient had an excellent response to high-dose chemotherapy with no major complication. The presence of extrarenal involvement in the testes and the retroperitoneal lymph nodes made the diagnosis of primary renal lymphoma debatable. However, considering the delay in diagnosis and the high proliferative rate of B-cell NHL, we might postulate that the disease had originated primarily in the kidneys. We recommend that in NHL cases with severe renal involvement, full-dose chemotherapy should be instituted with meticulous clinical and laboratory follow-up in order to improve clinical and renal failure status rapidly and to avoid further dissemination of NHL.

Acute Kidney Injury↗

Cerebrospinal fluid soluble CD27 levels in children with non-Hodgkin lymphomas.

The authors investigated the diagnostic value of cerebrospinal fluid (CSF) soluble CD27 (sCD27) for leptomeningeal involvement of non-Hodgkin lymphomas (NHL). Cytospin slides were prepared from CSF samples of 64 children treated for NHL. sCD27 levels were determined by sandwich ELISA method using two CD27 monoclonal antibodies. 8/194 (4.1%) samples were considered tumor-positive by cytology. Mean sCD27 values were 5.8 and 13.8 U/mL in tumor-negative and tumor-positive samples, respectively (p =.18). 26/194 samples were false positive and 2/194 false negative (cutoff: 7 U/mL) (sensitivity, 75 %; specificity, 86%; positive predictive value, 18.8%; negative predictive value, 98.8%; accuracy, 85.6%). With these results, the value of adding sCD27 determination to the cytological CSF examination remains questionable.

Adolescent↗

Value of surveillance imaging in the management of medulloblastoma.

BACKGROUND: To investigate the value of surveillance scanning for the detection of recurrences in medulloblastoma. PROCEDURE: The charts of 95 patients with medulloblastoma were retrospectively reviewed. Information regarding the patient characteristics, treatment modalities, dates, types and results of CT and MRI studies, the frequency with which recurrences were identified on surveillance images, changes in patient management, outcome of the patients following recurrences, and survival data were analyzed. RESULTS: Thirty-one patients had a recurrence of tumor in the central nervous system; none experienced extraneural relapses. Of all recurrences, 21 were symptomatic and 10 were discovered by surveillance scans asymptomatically. None of the patients with a recurrence survived. For all 95 patients, 5-year overall and event-free survival rates were 47.1 and 49.8%, respectively. In patients with symptomatic and asymptomatic recurrences, the mean time to recurrence since initial diagnosis, the mean duration of survival post-recurrence, and the mean duration of overall follow-up were 19.2 and 26.1 months, 3.6 and 8.0 months, and 22.8 and 34.1 months, respectively. For 95 patients, 468 surveillance and 38 symptomatic images were reviewed as 313 CTs and 193 MRIs. Rate of diagnosis of recurrence per surveillance image was 2.1% (10/468). CONCLUSIONS: In our study, surveillance scanning brought no survival advantage since it detected a minority of recurrences. Longer survival achieved by early detection of recurrences might be a reflection of lead-time and length biases. Surveillance procedures will gain more importance as new effective therapeutic options are developed for recurrent medulloblastoma.

Adolescent↗

Hodgkin's disease and ataxia telangiectasia with pulmonary cavities.

Ataxia telangiectasia (AT) homozygotes have an increased risk for development of Hodgkin's disease (HD). Parenchymal lung involvement is not uncommon in HD; however, cavitary pulmonary lesions are quite unusual. We report on 3 cases of AT with HD who had mediastinal disease and parenchymal pulmonary involvement with cavitation. Of 6 AT patients in our HD series, 3 developed pulmonary cavities. The patients displayed pulmonary infiltration, cavitation in the lung parenchyma, and mediastinal enlarged lymph nodes on both plain chest X-rays and thoracic computed tomographies. No infectious etiologies were established for the pulmonary findings. Histopathological examination of open lung and mediastinal biopsies revealed HD, and all patients received multiagent chemotherapies. The outcome was fatal in all 3 patients. Respiratory infections are the principle cause for morbidity and mortality in AT patients. Reports on cavitating pulmonary lesions in HD are quite rare. Furthermore, data regarding the patterns of pulmonary involvement in AT patients with or without HD are lacking. The increased incidence of malignancies in AT patients may relate to immunodeficiency and to the chromosomal alterations identified.

Ataxia Telangiectasia↗

Glutathione S-transferase and P-glycoprotein expressions in neuroblastoma.

This study was planned to evaluate the prognostic role of glutathione S-transferase pi (GST-pi) and P-glycoprotein (P-gp) expressions in children with neuroblastoma. Sections from formalin-fixed paraffin-embedded tumor blocks from 52 neuroblastoma cases (17 with localized, 35 with advanced disease) were subjected to immunohistochemistry for P-gp and GST-pi expressions. The overall number of tumors positive for P-gp and GST-pi were 19 (36.5%) and 21 (40.4%), respectively. Twenty-two tumors were negative for both GST-pi and P-gp expressions, whereas 10 expressed both proteins. The distribution of staining status of samples in the groups of both proteins showed no significant difference. No relation between the expressions of both proteins and the clinical characteristics of the patients was demonstrable. The differenes between the survival rates of patients with positive and negative staining for P-gp expression were not statistically significant. Although 2 common mechanisms of multiple drug resistance, P-gp and GST-pi, might be responsible for drug resistance in neuroblastoma, this complex mechanism has no direct significant impact on prognosis. Multiple mechanisms at cellular levels are responsible for the resistance against antineoplastic therapies in neuroblastoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗