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Biomedical subjects

Canan Akyüz

Publications and source records attributed to Canan Akyüz.

At least 19 recordsLinked to original sources
PubMed2006

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↗
PubMed2006

Extraneural metastasis in intracranial tumors in children: the experience of a single center.

Our aim is to evaluate the clinical features and outcomes of children with primary central nervous system (CNS) tumors who develop extraneural metastasis (ENM). We retrospectively evaluated children diagnosed with primary CNS tumors treated at our institution between 1972 and 2004. Of 1,011 patients these tumors, 10 (0.98%) developed ENM. The histopathologic diagnosis was medulloblastoma in six patients, germ cell tumors in two patients, and ependymoma and atypical teratoid rhabdoid tumor (ATRT) in one patient each. In six patients, the primary tumor was located in the posterior fossa; it had a supratentorial location in the patient with ATRT, was located in the sellar and suprasellar region in the two patients with germ cell tumors, and was found in the distal spinal cord in the patient with an ependymoma. In two patients ENM was detected at the time of diagnosis. In other patients ENM developed between 9 and 25 months after diagnosis. Metastatic sites included bone, bone marrow, lung, cervical lymph nodes, liver, and paranasal sinuses. Of the 10 patients who developed ENM, 8 died of their disease 0.27-16.2 months (median, 2.60 months) after it was detected. One patient with dysgerminoma is alive, without disease, 117.80 months after diagnosis of the ENM. One patient with germ cell tumor is alive with disease 11.3 months after diagnosis of the ENM. Systemic metastasis to other extraneural sites is extremely rare in children with intracranial tumors. In our series the rate of ENM is 0.98%. The liver and lung are the most common site for metastasis, followed by the bone and bone marrow. The outcome is poor in patients with CNS tumors with ENM.

Adolescent↗
PubMed2006

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↗
PubMed2006

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↗
PubMed2006

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↗
PubMed2006

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↗
PubMed2006

Improved survival of children with wilms tumor.

To analyze changes in the overall survival (OS) rate of children with Wilms tumor treated in a single institute over nearly 30 years. This study included 327 children with a newly diagnosed Wilms tumor. Their median age was 3 years, and the male:female ratio was 1.1. Survival rates were analyzed according to the stage of disease, histopathology, and different treatment regimens used between 1972 and 1999. At diagnosis, 51.1% of patients had advanced stage disease. Ten patients had anaplasia, and; 97% (317 patients) of the tumors had favorable histopathology. The 10-year OS rate was 60.6% for the entire group, but varied according to the years in which the patients were treated, the chemotherapy regimen, and stage of disease. Patients treated during the periods of 1972 to 1979, 1980 to 1989, and 1990 to 1999 had 10-year OS rates of 48.5%, 64.3%, and 72.8%, respectively. The 10-year OS rate in children treated with actinomycin only was 36.7% compared with 48% for children treated with the actinomycin-D+vincristine regimen with a 3-month interval, 67% for the actinomycin-D+vincristine regimen with a 1.5-month interval, 54.5% for the poor-risk regimen (actinomycin-D, vincristine, cyclophosphamide, and adriamycin), and 53.4% for the SIOP-9 protocol. Children with stage I to IV disease had 10-year OS rates of 75%, 77.1%, 54.4%, and 30.4%, respectively. The 10-year OS rates for children with stage III and IV disease increased from 46.4% and 13.4% for patients treated between 1972 to 1979 period to 75% and 54.5% for children treated during 1990 to 1999. The 10-year OS rate for children with Wilms tumor improved as treatment strategies evolved, illustrating that pediatric oncology in Turkey is developing parallel to the Western world.

Adolescent↗
PubMed2006

The first medical humanities programme in Turkey.

THE MEDICAL HUMANITIES: The arts and humanities have been considered a recreational activity related to the interests and talents of the doctor, rather than to their practice of medicine. GOOD MEDICAL PRACTICE COURSE: At Hacettepe University, the 'good medical practice course' was added to the curriculum in September 2004. The goals of this course are to help the students achieve the skills and attitudes of a good doctor and to become competent in caring for and communicating with patients. IMPLEMENTATION: As a part of the programme, in the first 3 years students prepared 526 projects concerned with medical humanities in the broad areas of 'medicine and art', 'medicine and history' and 'man and medicine'. They presented 72 of the projects as short communications at the Medical Humanities Congress and the remaining projects as posters. Each project was also to be prepared as a portfolio. PROGRAMME EVALUATION: At the end of the programme, a questionnaire was given to both the students and the tutors to evaluate the course. The part of the programme rated most difficult was the medical humanities section, according to 67.1% of the students. They commented that it took a great deal of time to research and prepare the projects. PROPOSED CHANGES: The new concept and the extra workload, in addition to new medical knowledge, confused all the students. We have made some changes to the programme and have decided to develop a number of new activities. CONCLUSION: 'Medical humanities' is a new concept for almost all the students and the faculty; it needs to be well defined.

Clinical Competence↗
PubMed2006

The efficacy of liver transplantation in malignant liver tumors associated with tyrosinemia: clinical and laboratory findings of five cases.

To evaluate clinical and laboratory findings of these patients and the efficacy of liver transplantation in children with hepatocellular carcinoma (HCC) and hepatoblastoma (HB) associated with tyrosinemia. Among 113 children with liver tumors diagnosed between 1972 and 2004 five patients had HCC or HB associated with tyrosinemia. The age at diagnosis of the HCC or HB ranged from 9.5 to 17 yr and male:female ratio was 1:4. During regular clinic visits for tyrosinemia, elevated alpha-fetoprotein (AFP) was detected in all patients. AFP levels ranged between 13.7 and 29 340 IU/mL. Radiological studies including ultrasound, computed tomography and magnetic resonance imaging showed heterogeneous parenchyma and nodules in the liver. The patients did not have any metastatic disease. The time from diagnosis of tyrosinemia to HCC or HB ranged from 9.25 to 15.25 yr. Histopathologically, four patients have been diagnosed as HCC and one patient had HB. All patients were given chemotherapy including cisplatin and adriamycin. In three patients, living-related liver transplantation was performed. They had no treatment after transplantation. All of them are disease free. One patient was treated with chemotherapy and right hepatectomy. She had no suitable donor for living-related liver transplantation. Three months after completing chemotherapy, she had recurrent tumor in the left lobe of the liver and she died with progressive disease. The last patient whose parents were not suitable as donors for living-related liver transplantation is waiting for a deceased donor graft. All patients had limited disease to liver due to close clinical and radiological follow up for tyrosinemia. In these patients liver transplantation is curative both for liver tumor and tyrosinemia.

Adolescent↗
PubMed2006

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↗
PubMed2006

Second malignant neoplasms following the treatment of brain tumors in children.

We investigated retrospectively 992 children with central nervous system tumors who were treated at our center between 1970 and 2004. All of the patients were treated by surgery, chemotherapy, and/or radiotherapy. Six patients developed second malignant neoplasms, and their clinical and histopathologic characteristics are reviewed in this article. The second malignant neoplasms were diagnosed as non-Hodgkin lymphoma, myelodysplastic syndrome, basal cell carcinoma, malignant melanoma, Kaposi sarcoma, and high-grade neuroectodermal tumor. The initial diagnoses were ependymoblastoma in one, medulloblastoma in three, and low-grade astrocytoma in two patients. The median latency time was 3.03 years (range 0.39-22.93 years). The outcome varied according to the histopathologic type of the second tumor. The patients who developed non-Hodgkin lymphoma and myelodysplastic syndrome died of progressive disease. The patients with second skin neoplasms are alive as of the time of this writing. The patient with Kaposi sarcoma developed one of the rare reported second malignant neoplasms following a primary brain tumor in childhood. A wide spectrum of second malignant neoplasms was detected after treatment of primary brain tumors with surgery, radiotherapy, and chemotherapy. Long-term follow-up is therefore necessary for the child who has survived a primary central nervous system tumor.

Brain Neoplasms↗
PubMed2005

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↗
PubMed2005

Prognostic significance of metastatic site at diagnosis in Wilms' tumor: results from a single center.

The purpose of this study was to identify the prognostic significance of pulmonary and liver involvements present at diagnosis in children with Wilms' tumor. From 1971 to 2002, 57 patients with stage IV Wilms' tumor were diagnosed, treated, and followed in the authors' institution. Metastases were detected by chest radiography, abdominal ultrasonography, and/or thoracoabdominal computed tomography. Nephrectomy with tumor resection was performed and appropriate chemotherapy was given to all the patients. The Kaplan-Meier survival method was used to calculate survival. The log-rank test was used to compare the groups with respect to survival. The age range was 1.25 to 15 years (median 4 years). Thirty-seven patients had only lung metastases, 12 had only liver metastases, 6 had both lung and liver metastases, 1 had adrenal gland metastases, and 1 had other site metastases. The overall survival rate in the whole group was 37.1%. The overall survival rates for lung and liver metastases were 50.2% and 16.6%, respectively. The overall survival rates were significantly different between the two groups (P = 0.005). Only one patient survived in the group with liver involvement. Liver involvement at diagnosis indicates a worse prognosis than lung involvement. Wilms' tumor patients with liver metastases should be treated with more intensive regimens than those with lung metastases.

Adolescent↗
PubMed2005

Cavoatrial tumor extension in children with wilms tumor: a retrospective review of 17 children in a single center.

The aim of this study was to evaluate the clinical characteristics and treatment results of 17 children with cavoatrial tumor extension of Wilms tumor. Of the 360 Wilms tumors diagnosed between 1980 and 2000, 17 patients with intracaval thrombus were identified from the medical records at the pediatric oncology department of Hacettepe University. The following data were collected and reviewed: age, sex, presenting symptoms, tumor site, presence of anaplasia, stage, associated congenital anomalies, localization of tumor thrombus, radiologic findings, type and duration of preoperative chemotherapy, response to preoperative chemotherapy, recurrences, and survival. The frequency of cavoatrial extension in this group was 4.7% (15 in the inferior vena cava and 2 in the right atrium). Fourteen patients received preoperative chemotherapy consisting of two-drug regimen (vincristine and actinomycin D) ranging from 1 to 12 weeks (median 4 weeks). Since intravascular invasion is often asymptomatic, a careful radiologic examination to detect tumor thrombus before surgery is essential. There is no need for aggressive surgery in the presence of tumor thrombus. It may be resolved by preoperative chemotherapy. Surgical removal of the thrombus should be considered in the presence of life-threatening tumor thrombosis at diagnosis and in patients who had residual thrombus after chemotherapy.

Child↗
PubMed2005

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↗
PubMed2005

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↗
PubMed2004

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↗