Prevalence of Factor V Leiden and other thrombophilic traits among Cretan children with malignancy

The prevalence of thrombophilic traits, which might further enhance the risk of thrombotic complications in children treated for cancer, varies significantly among different populations.

To evaluate the prevalence of common thrombophilic traits of the East Mediterranean Region, among native Cretan children treated for malignancy.

Blood samples were consecutively collected from 31 native Cretan children treated for acute lymphoblastic leukaemia (n = 19) or other malignancies (n = 12) over 3 years. A molecular diagnosis based on the presence of Factor V Leiden (FVL), as well as on PT G20210A and MTHFR C677T mutation (in 14 patients) using PCR was applied. Patients who had central venous catheters (n = 29) were treated with an intensified thromboprophylaxis protocol that had been previously established in our institution.

The prevalence of the FVL mutation was 19.4% (95% CI = 5-32). The allele frequency is estimated at 11.3% (95% CI: 3.5-19.1) which is higher than that reported for the population of the mainland of Greece. The prevalence of the PT G20210A and MTHFR C677T mutation was 14.3 and 71.4%, respectively (corresponding allele frequencies 7.1 and 50%, respectively). Only one patient developed thrombosis, having although no thrombophilic trait.

Thrombophilic traits were relatively common in this group of native Cretan children treated for malignancy. Thromboprophylaxis should be considered in Cretan children in the presence of known acquired risk factors for thrombosis, but a larger prospective to study is first needed.