Maternal smoking during pregnancy and risk for childhood leukemia: a nationwide case-control study in Greece and meta-analysis.

BACKGROUND: Maternal smoking during pregnancy has been often implicated in the development of childhood leukemia with ambiguous results. Hence, we conducted a meta-analysis aiming to summarize current evidence and quantify any tentative impact. PROCEDURE: We retrieved one cohort (553 leukemias compared to 1,440,542 children), 20 case-control studies and also analyzed the updated Greek case-control dataset with unpublished data, yielding in total 11,092 cases and 25,221 controls. RESULTS: Odds ratios reported in the studies included ranged from 0.70 to 2.20 for acute lymphocytic (ALL) and from 0.60 to 2.17 for acute myelocytic leukemia (AML). The combined effect regarding the association of maternal smoking (any vs. no) and leukemia risk was 1.03 for ALL (95% CI = 0.95-1.12, random effects model) and 0.99 for AML (95% CI = 0.90-1.09, fixed effects model). The results remained unchanged when sensitivity analyses were undertaken of studies reporting same maternal smoking periods, those focusing only on childhood leukemia deaths or investigations which did not clearly define AML subtype. CONCLUSIONS: The findings of the meta-analysis challenge the limits of traditional epidemiology to provide sound inferences when point estimates of constituent studies range around the null. In particular, this study provides no support to a hypothesis linking maternal smoking during pregnancy with subsequent development of main childhood leukemia subtypes. Further investigations employing molecular and genetic epidemiology, however, might be needed in the hope to reveal even minimal risks pertaining individuals with specific susceptibility to tobacco compounds who sustain high environmental exposures prenatally or postnatally.

Propranolol treatment for severe infantile hemangiomas: a single-centre 3-year experience.

AIM: To evaluate the effectiveness, safety and tolerability of propranolol as single-agent treatment in patients with problematic, proliferative-phase, infantile hemangiomas (IHs). METHODS: Oral propranolol was administered at a dose of 2 mg/kg/day to 28 children. Cardiologic evaluation was performed before treatment initiation. Hemodynamic variables and blood glucose levels were monitored during the first 24 h of treatment, while the children were hospitalized. Clinical response and tolerance were assessed every month, along with photographic documentation. Macroscopic regression was considered the reduction >90% in the size of the IHs. RESULTS: Effects on colour and growth were observed within the first month in all cases. Twenty-four patients completed treatment after a mean duration of 7.56 months, and their hemangiomas were successfully regressed. Propranolol was administered again, with satisfactory results, in three patients (12.5%) because of hemangioma regrowth. Satisfactory response is noticeable in ongoing cases. Episodes of hypotension were noted in four patients. There were no treatment interruptions because of side effects. CONCLUSIONS: Propranolol, as first-line treatment, yielded excellent results with very good clinical tolerance and also seems to be effective in relapses. The optimal duration of the treatment remains to be defined by long-term observation.

Improvement of sun-related knowledge and protection practice.

The aim of this study was to examine changes in sun-related knowledge and sun protection practice among Greek mothers and children during 1993-2002. A total of 315 mothers in 1993 and 295 mothers in 2002, with their 649 and 491 children respectively, were randomly selected to answer the same questionnaire on sun-related issues. Sun knowledge and protection practice were determined by an index score. Significantly more mothers in 2002 compared to 1993 had 'good' (58.9% versus 16%) and 'excellent' levels (28% versus 6%) of sun knowledge (p<0.001). In 2002, 40% of the mothers and children (versus 27% and 30% each in 1993) had 'good' levels of sun protection practice, while 28% of the mothers and 26% of the children (versus none in 1993) reported 'excellent' levels (p<0.001). Knowledge and sun protection practice were significantly improved, probably due to an information campaign conducted between both surveys.

Recent thymic emigrants and prognosis in T- and B-cell childhood hematopoietic malignancies.

The concentration of T-cell receptor rearrangement excision DNA circles (TRECs) in peripheral blood mononuclear cells (PBMCs) is currently known to be a marker of recent thymic emigrants. We evaluated the hypothesis that TREC values would be lower in childhood T-cell hematopoietic malignancies than in childhood B-cell acute lymphoblastic leukemia (ALL) or healthy controls because the former category may reflect compromised thymic function. From the Greek national childhood leukemia/lymphoma database we obtained all 30 available T-cell leukemia/non-Hodgkin's lymphoma cases, 30 age- and sex-matched childhood B-cell origin cases of ALL and 60 healthy hospital controls. We compared TREC levels in PBMCs using a real-time PCR assay. There was highly significant reduction of TREC values in children with T-cell malignancies (median 3,100 TRECs/10(6) PBMCs), whereas children with B-cell origin ALL had slightly but nonsignificantly lower TREC values compared to healthy children (medians 19,300 and 22,500 TRECs/10(6) PBMCs, respectively). During a median follow-up period of about 19 months, only 4 children died. All of them had a T-cell hematopoietic malignancy and relatively low TREC values. The number of TRECs was higher among healthy girls than among healthy boys, and a similar pattern was evident in T-cell malignancies. It appears that there is a pattern of concordance of high TREC values with better disease prognosis in hematologic childhood malignancies. This applies to specific disease entities with better prognosis (B-cell origin ALL having higher TREC values than T-cell leukemia/lymphoma) and to gender, another important predictor of prognosis conditional on disease entity (girls having higher TREC values than boys); however, it may also be true for the survival of individual patients. These preliminary findings can be used as hypothesis-generating indications that should be confirmed in larger data sets.