Patients with leukaemia-like reactions have a low mortality rate. Because the disease has a clear etiology, the leukaemia-like reaction usually disappears after aggressive treatment and the primary disease is cured or improves, the prognosis is better and the patient does not usually die, except when the primary disease is an infection and causes systemic infection, which may affect the patient’s life cycle. In addition, the prognosis for leukaemia-like reactions due to neoplastic factors is relatively poor and, if left untreated and the disease progresses to an intermediate or advanced stage, the patient’s quality of life is reduced and can be life-threatening.