Lymphoma is a malignant condition affecting lymphoid cells that can originate in lymph nodes (nodal disease) or tissues outside of lymph nodes (extranodal disease). Hodgkin lymphoma usually is nodal and is defined by the presence of Reed-Sternberg cells. All other lymphomas are considered non-Hodgkin lymphoma. Lymphomas are stratified into aggressive forms and more slow-moving, indolent forms. Bone involvement can be primary or secondary1.