Various drugs have been added to different treatment regimens in order to improve the response rate in patients with Acute Lymphoblastic Leukemia, however, it has been shown that adding Bortezomib to the relapsing regimen improves the proportion of second complete remissions without increasing chemotherapy toxicity. Therefore, proteasome inhibitors can drastically modify the prognosis of patients, since their synergy with drugs such as steroids has positioned them as an attractive strategy.

Mortality associated with leukemia has decreased due to the use of various chemotherapy combinations, the addition of new agents, or the chemical modification of existing drugs. Despite advances in treatment, the prognosis in the adult population continues to be unfavorable. About 25% of the patients will be refractory to the first treatment regimen and the rest will have a disease-free survival below 40%. The chemotherapy intensity reduction strategy based on risk stratification according to Minimal Residual Disease (MRD) is a strategy used by various pediatric centers in order to detect patients at high risk of relapse.

Inclusion Criteria:

• Patients with a confirmatory diagnosis of Acute Lymphoblastic Leukemia relapsed to bone marrow described with more than 5% blasts in bone marrow at any stage of treatment or positivity of minimal residual disease at any stage of treatment.
• Patients who have signed their informed consent from the institution for hospitalization, and accepted the performance of the bone marrow study, and the administration of chemotherapy.

Exclusion Criteria:

• Patients with a diagnosis of phenotypic leukemia or bilinear leukemia
• Patients treated only with palliative regimen or transfusion support
• Patients without the administration of prophylaxis to the central nervous system by intrathecal chemotherapy
• Patients with lymphoblastic leukemia with a positive Philadelphia chromosome
• Patients with severe comorbidities may put treatment therapy at risk.
• Patient with a history of cardiac toxicity or arrhythmias associated with treatment

All participants and their information will be managed by intern investigators and will be kept secure for personal data protection according to Mexican laws.