Epidemiology of venous thromboembolism in children with malignant diseases: a single-center study of the Belarusian Center for Pediatric Oncology and Hematology.

ABSTRACT

BACKGROUND: Venous thrombosis is a complication of treatment of children with cancer but studies devoted to the epidemiology of thrombosis in children with cancer are rare and data are scanty. OBJECTIVE: To determine the prevalence and clinical characteristics of VT as a secondary complication in children with malignant disease and to estimate the ten-year experience of our hospital. METHOD: Retrospective analysis of data of Children's Cancer Subregistry of Belarus, which included information about age, gender, details of diagnosis, classification of malignant neoplasm according to ICD-10, treatment protocol and outcome. Clinical information was obtained from case histories. RESULTS: For the specified period, 2061 children with newly diagnosed cancer and 44 cases of VT have been registered. Among VT cases, hematological malignancies prevailed (32 of total 44). Higher incidence of VT in AML and APL groups was shown (p<0.05). In patients with VT, boys (M/F = 1,6/1) and teenagers prevailed (65,9%). Of 44 patients, 33 had catheter-associated thrombosis (CAT). Almost all CAT (91,7%) were in the upper venous system. Children with non-CAT (11 out of 44) had more prolonged duration of immobilization, than children with CAT (p<0.05) and in this group, thrombosis affected predominantly the lower limb (9 out of 11). CONCLUSION: The present study has shown that venous thrombosis occurs significantly more often in children with AML and APL. Prevalence of boys in patients with venous thrombosis has been noted. Increased frequency of VT events in teenagers has been observed and the provoking role of CVC and immobilization for thrombosis has been confirmed.