Childhood leukemia and lymphoma: time trends and factors affecting survival in five Southern and Eastern European Cancer Registries.

PURPOSE: Within Europe, incidence and mortality rates of childhood leukemia and lymphoma are rather heterogeneous. The present study comprising data from five Southern and Eastern European Cancer Registries aims to compare time trends and examine whether sociodemographic variables, clinical parameters, and proxies of efficient care affect survival. METHODS: Data spanning 1996-2010 were obtained for a total of 3,041 newly diagnosed childhood leukemia and 1,183 lymphoma cases reported by the Greek Nationwide Registry for Childhood Hematological Malignancies, Bulgarian National Cancer Registry, Moscow Region and Turkey (Antalya and Izmir) Cancer Registries. Poisson modeling for the evaluation of time trends and multivariate Cox regression analysis for the assessment of prognostic factors were performed. RESULTS: The incidence of leukemia was increasing in all cases, with Bulgaria and Greece presenting statistically significant annual changes (+3.5, and +1.7 %, respectively), followed by marginally increasing trends in Izmir and Moscow; by contrast, there was a remarkable, statistically significant, decreasing mortality trend for leukemia. Rates for lymphoma remained flat. Greece experienced almost twofold better survival rates for both leukemia and lymphoma, probably due to its higher socioeconomic status during the study period. Overall, patients with leukemia living in rural areas had a 28 % lower prognosis (RR: 1.28, 95 % CI 1.03-1.59), pointing to effects of remoteness, when the most privileged country (Greece) was excluded from the analysis. CONCLUSIONS: The favorable mortality trends highlight the progress in Southern-Eastern European countries along their trajectory to converge with Northern-Western EU counterpart states. Socioeconomic status may act as a multipotent factor underlying the study findings.

Nutrition in early life and risk of childhood leukemia: a case-control study in Greece.

PURPOSE: There is a paucity of findings concerning the role of diet in childhood leukemogenesis, whereas the results are equivocal and the studies heterogeneous with regard to food items examined. This case-control study investigates the association of childhood leukemia with food groups, macronutrient consumption, total energy intake and adherence to Mediterranean diet among children aged 5-14 years in Greece. METHODS: A total of 139 consecutive, incident leukemia cases out of which 121 were acute lymphoblastic leukemia were derived from the Nationwide Registry for Childhood Hematological Malignancies along with one : one age- and gender-matched hospital controls. Information on socio-demographic, maternal and child variables and dietary habits was obtained through in-person interviews with the guardians/children. Multiple logistic regression was performed with adjustment for birth weight and possible confounding variables. RESULTS: Higher consumption of added lipids was associated with an increased risk of childhood leukemia, whereas consumption of milk and dairy products with reduced risk. From the macronutrient analysis, a borderline trend linking high protein intake with reduced childhood leukemia risk was observed. CONCLUSION: Consumption of milk and dairy products in the first year of life may protect against childhood leukemia possibly through vitamin D actions, while added lipids may increase the risk through various mechanisms. These results offer a holistic evaluation of children's nutrition and suggest that dietary habits in the early years of life may contribute to the prevention of childhood leukemia.

Allergy and risk of acute lymphoblastic leukemia among children: a nationwide case control study in Greece.

BACKGROUND: Several reports point to inverse associations between allergies and ALL; yet, no study has explored this link using both self-reported-data on allergic history and biomarkers of atopic sensitization. METHODS: Clinical information for the variables of interest was available for 252 out of 292 cases of childhood (0-14 years) ALL, newly diagnosed across Greece over a 4.5 year period as well as for 294 hospital controls. Allergen-specific-IgEs, as markers of allergic predisposition, against 24 most prevalent respiratory and food allergens, were determined, using an enzyme immunoassay procedure for 199 children with ALL and 113 controls. Cases were compared with controls through frequency distributions and unconditional multiple logistic regression models to estimate odds ratios (ORs) and 95% confidence-intervals (CIs) regarding associations of allergy with childhood ALL. RESULTS: Self-reported-allergic history overall (OR: 0.49, 95% CI: 0.34-0.72) and practically each one of its main components (respiratory, food, any other clinical allergy) were strongly and inversely associated with ALL. Likewise, the serum IgE inverse association was of the same magnitude (OR: 0.43, 95% CI: 0.22-0.84) mainly contributed by food IgE (OR: 0.39, 95% CI: 0.18-0.83). CONCLUSION: Beyond the already established inverse association of allergic history with childhood ALL, a same magnitude association is evident when serologic markers of allergic predisposition are used as an alternative measure of allergy. Further research with more appropriate study designs is needed to better understand possible associations between prior allergy and childhood ALL risk.

Carcinoid tumors of the appendix in children: experience from a tertiary center in northern Greece.

BACKGROUND AND OBJECTIVE: Carcinoid tumors of the appendix are rare in childhood and usually have a benign clinical course. Their incidence in appendectomy specimens ranges from 0.1% to 0.9%. The aim of the study was to report the frequency, clinical presentation, tumor characteristics, and outcome of children with appendiceal carcinoid treated in a pediatric oncology department. PATIENTS AND METHODS: All of the cases referred during a 19-year period (1990-2008) were studied retrospectively. Demographics, clinical presentation, tumor characteristics, and follow-up results were recorded. RESULTS: Among 839 admissions, 19 patients (9 boys) with appendiceal carcinoid were identified during the study period. Their median age was 10.5 years (range 4.5-13.2 years). In all of the cases, diagnosis was established after appendectomy. The mean tumor diameter was 4.55 (± 3.45) mm (range 1-15 mm). Concomitant appendicitis was diagnosed in 12 patients. In 18 children tumor size was ≤ 10 mm and did not infiltrate surrounding tissues. In 1 patient the size was 15 mm and a microscopic rupture of the appendix with infiltration of the surrounding fat was present. All of the tumors were located at the tip of the appendix and were of the classic histological type. Staging and follow-up consisted of abdominal ultrasound, chest and abdominal computed tomography scans, Tc bone scan, urine 5-hydroxylindoloacetic acid levels, and 111In octreotide scan. No patient had metastases requiring further therapeutic interventions. No relapses or other neoplasms occurred during a median follow-up period of 45 months (range 6-118 months). CONCLUSIONS: Carcinoid tumors of the appendix in children are rare. Long-term follow-up revealed that a good prognosis is possible provided they are diagnosed and surgically removed at an early stage.

Isolated central nervous system recurrence in a child with stage IV neuroblastoma.

Neuroblastoma is the most common extracranial solid tumor in children. Survival rates have improved due to advances in treatment with aggressive chemotherapy and autologous bone marrow transplantation. Usual sites of recurrence include the site of primary tumor, residual gross disease, bone, bone narrow, liver, and lungs. The authors describe a 16-month-old boy with stage IV extracerebral primary neuroblastoma who died because of an isolated central nervous system (CNS) relapse. The CNS is a rare site of relapse that is, however, increasingly diagnosed due to prolonged survival. Criteria to identify patients at increased risk of CNS relapse are urgently needed. High-risk patients should be followed-up with brain and spine magnetic resonance imaging (MRI) for timely detection of metastases and appropriate management.