Table 1: Staging of non-Hodgkin lymphoma (NHL) [8].

Stage 1 NHL is limited to one lymph node group (e.g., neck, underarm, groin, etc.) above or below the diaphragm, or NHL is in an organ or site other than the lymph nodes (extranodal) but has not spread to other organs or lymph nodes.
Stage 2 NHL is limited to two lymph node groups on the same side of the diaphragm, or NHL is limited to one extranodal organ and has spread to one or more lymph node groups on the same side of the diaphragm.
Stage 3 NHL is in two lymph node groups, with/without partial involvement of an extranodal organ or site above and below the diaphragm.
Stage 4 NHL is extensive (diffuse) in one organ or site, with/without NHL in distant lymph nodes.