B2M and lymphoma: In patients with partial or complete remission after three cycles of chemotherapy, the median β2M was in the total patient's group 1,8 mg/L (range: 1,0–4,29), in the group of aggressive lymphomas 1,83 mg/L (range: 1,0–4,29 mg/L), in the group with extranodal disease presentation 1,85 mg/L (range: 1,0–4,29 mg/L), and in the group with nodal disease presentation 1,72 mg/L (range: 1,10–3,98 mg/L).