Purpose: Asparaginases, key agents in treatment of acute lymphoblastic leukemia (ALL), are associated with venous thromboembolism (VTE). While risks of short-acting asparaginase-related VTE is well-known, we studied VTE incidence and risk factors in adult ALL patients treated with and without long-acting pegylated asparaginase (PegA).
Methods: Single-center, retrospective analysis of 89 ALL patients treated with (n = 61) or without (n = 28) PegA at Greenebaum Comprehensive Cancer Center. Reviewed patient and disease characteristics, treatment, and VTE incidence.
Results: VTE during treatment occurred in 31 patients (35%), and was associated with PegA (p = 0.001) and Philadelphia chromosome negativity (p = 0.002). Among PegA recipients, VTE was associated with a significantly higher mean body mass index (BMI) of 31.3 kg/m2 (p = 0.037), and was more common with pre-T/T cell compared to pre-B/B cell ALL (68.2% vs. 33.3%, p = 0.009). Antithrombin-III (ATIII) levels were measured for 26 patients; 16 (61.5%) were < 50%. Of those, 8 (50%) experienced VTE, while 3 of 10 (30%) patients with ATIII levels ≥ 50% experienced VTE. VTE occurred in 7 of 13 (54%) of patients who received ATIII repletion. There was a trend toward a higher incidence of VTE in the PegA group among patients with non-O compared to O blood type (55.9% vs. 33.3%, p = 0.079) as well as those with a higher hemoglobin at diagnosis (9.3 vs 8.1 g/dL, p = 0.056).
Conclusion: This study confirms PegA as a risk factor for VTE in patients with ALL. Risk factors among those receiving PegA include higher BMI and pre-T/T cell ALL. ATIII repletion was not shown to be protective against VTE. There was a higher incidence of VTE in patients who received PegA with non-O compared to O blood type, but the precise correlation is uncertain.
Keywords: ALL; Acute lymphoblastic leukemia; Pegaspargase; Pegylated-asparaginase; Venous thromboembolism.