Impaired fibrinolysis and increased clot strength are potential risk factors for thrombosis in lymphoma.

Thrombosis and bleeding are significant contributors to morbidity and mortality in patients with hematological cancer, and the impact of altered fibrinolysis on bleeding and thrombosis risk is poorly understood. In this prospective cohort study, we investigated the dynamics of fibrinolysis in hematological cancer patients. Fibrinolysis was investigated prior to treatment and three months after treatment initiation. A dynamic clot formation and lysis assay was performed beyond the measurement of plasminogen activator inhibitor 1, tissue- and urokinase-type plasminogen activators (tPA and uPA), plasmin-antiplasmin complexes (PAP), α-2-antiplasmin activity, and plasminogen activity. Clot initiation, clot propagation, and clot strength were assessed using thromboelastometry (ROTEM®). A total of 79 patients were enrolled. Lymphoma patients displayed impaired fibrinolysis with prolonged 50% clot lysis time compared to healthy controls (p = 0.048). They also displayed decreased clot strength at follow-up compared to at diagnosisp (p = 0.001). A patient with amyloid-light-chain amyloidosis having overt bleeding at diagnosis displayed hyperfibrinolysis, indicated by a reduced 50% clot lysis time, α-2-antiplasmin activity, and plasminogen activity and elevated tPA and uPA. A patient with acute promyelocytic leukemia also displayed marked hyperfibrinolysis with very high PAP indicating extreme plasmin generation, and clot formation was not measurable probably due to the extremely fast fibrinolysis. Fibrinolysis returned to normal after treatment in both patients. In conclusion, lymphoma patients showed signs of impaired fibrinolysis and increased clot strength, whereas hyperfibrinolysis was seen in patients with acute promyelocytic leukemia and light-chain amyloidosis. Thus, investigating fibrinolysis in hematological cancer patients could have diagnostic value.