Safety and Efficacy of Anticoagulation Therapy in Paediatric Patients With Solid Tumours or Lymphomas at Risk of Thrombocytopenia: A Retrospective Study.

[BACKGROUND] Patients with solid tumours or lymphomas have an increased risk of thromboembolism (TE) and thrombocytopenia. Evidence-based strategies for anticoagulation therapy (ACT) for patients with thrombocytopenia are limited. We examined the impact of thrombocytopenia on ACT administration and bleeding incidence in children with solid tumours or lymphomas.

[METHODS] A total of 38 patients with solid tumours or lymphoma and TE were reviewed for demographics, cancer and therapy, platelet counts during ACT, ACT dosing, TE details and outcome, and bleeding episodes.

[RESULTS] A total of 54 TEs were diagnosed in 38 patients (mean age: 7.59 years [range: 0.1-18 years]). The most common underlying malignancies were neuroblastoma (15.8%), osteosarcoma (10.5%), germ cell tumours (10.5%) and hepatoblastoma (10.5%). Most patients (94.7%) completed the prescribed duration of ACT, with a median duration of 3.04 months (range: 0.36-12.5 months). A total of 24 out of 26 procedures were completed without bleeding complications among 20 patients. Bleeding events occurred in five patients (13.1%); however, only one minor bleed occurred in a patient with ACT and concurrent thrombocytopenia. Of the four bleeds not associated with thrombocytopenia, two were due to surgery, one was cystitis-associated and one was mild haematochezia. Complete resolution of TE was achieved in 38 clots (70.3%) in 26 patients, partial resolution in 8 clots (14.8%) of 6 patients, 6 stable clots (11.1%) in 5 patients, 1 patient lacked information on resolution and 1 patient's thrombus was a rhabdomyoma and was excluded.

[CONCLUSION] Full dose low molecular weight heparin (LMWH) ACT administration is safe and effective in paediatric patients with lymphomas and solid tumours at risk of thrombocytopenia.