Lymphoma, lymphoblastic: A rapidly moving, aggressive form of lymphoma that is most often seen in children or young adults. Since it is a tumor consisting of early lymphocyte precursors (lymphoblasts) it is believed to represent the same disease entity as acute lymphoblastic leukemia (ALL). Lymphoblastc lymphoma is a term that has been used in the past to refer to the presence of the abnormal lymphoblasts primarily in the lymph nodes. The World Health Organization (WHO) classification has unified lymphoblastic lymphoma and lymphoblastic leukemia into one entity known as precursor B- or T-cell lymphoblastic leukemia/lymphoma. Treatment may include chemotherapy, radiation, surgery, medications, and bone marrow transplant.