Relapsed or refractory disease
Arsenic trioxide (As2O3) is currently being evaluated for treatment of relapsed/refractory disease. Remission with arsenic trioxide has been reported. Studies have shown arsenic reorganizes nuclear bodies and degrades the mutant PML-RAR fusion protein. Arsenic also increases caspase activity which then induces apoptosis. It does reduce the relapse rate for high risk patients. In Japan a synthetic retinoid, tamibarotene, is licensed for use as a treatment for ATRA-resistant APL. Investigational agents
Some evidence supports the potential therapeutic utility of histone deacetylase inhibitors such as valproic acid or vorinostat in treating APL. According to one study, a cinnamon extract has effect on the apoptotic process in acute myeloid leukemia HL-60 cells. Prognosis
Prognosis is generally good relative to other leukemias. Because of the acuteness of onset compared to other leukemias, early death is comparatively more common. If untreated, it has median survival of less than a month. It has been transformed from a highly fatal disease to a highly curable one. The cause of early death is most commonly severe bleeding, often intracranial hemorrhage. Early death from hemorrhage occurs in 5–10% of patients in countries with adequate access to healthcare and 20–30% of patients in less developed countries. Risk factors for early death due to hemorrhage include delayed diagnosis, late treatment initiation, and high white blood cell count on admission. Despite advances in treatment, early death rates have remained relatively constant, as described by several groups including Scott McClellan, Bruno Medeiros, and Ash Alizadeh at Stanford University.Relapse rates are extremely low.
Anticoagulation such as heparin, intravenously (IV) or injectable (shot) can be given while inpatient and followed by heparin. A recent trial in 2015,  the Cervical Artery Dissection in Stroke Study (CADISS), examined the efficacy of antiplatelet and anticoagulation treatment with the primary endpoint of ipsilateral stroke or death in individuals with symptomatic dissections. The CADISS trial revealed no significant difference in efficacy of antiplatelet and anticoagulant drugs in preventing strokes or death, but did note that strokes were rare in either group, and rarer than what has been reported in observational studies. == References ==