Sarcoma in the context of Splenic tumor

Amoeboid movement is the most typical mode of locomotion in adherent eukaryotic cells. It is a crawling-like type of movement accomplished by protrusion of cytoplasm of the cell involving the formation of pseudopodia ("false-feet") and posterior uropods. One or more pseudopodia may be produced at a time depending on the organism, but all amoeboid movement is characterized by the movement of organisms with an amorphous form that possess no set motility structures.

Movement occurs when the cytoplasm slides and forms a pseudopodium in front to pull the cell forward. Some examples of organisms that exhibit this type of locomotion are amoebae (such as Amoeba proteus and Naegleria gruberi,) and slime molds, as well as some cells in humans such as leukocytes. Sarcomas, or cancers arising from connective tissue cells, are particularly adept at amoeboid movement, thus leading to their high rate of metastasis.

Epstein–Barr virus–associated lymphoproliferative diseases (also abbreviated EBV-associated lymphoproliferative diseases or EBV+ LPD) are a group of disorders in which one or more types of lymphoid cells (a type of white blood cell), i.e. B cells, T cells, NK cells, and histiocytic-dendritic cells, are infected with the Epstein–Barr virus (EBV). This causes the infected cells to divide excessively, and is associated with the development of various non-cancerous, pre-cancerous, and cancerous lymphoproliferative disorders (LPDs). These LPDs include the well-known disorder occurring during the initial infection with the EBV, infectious mononucleosis, and the large number of subsequent disorders that may occur thereafter. The virus is usually involved in the development and/or progression of these LPDs although in some cases it may be an "innocent" bystander, i.e. present in, but not contributing to, the disease.

EBV-associated LPDs are a subcategory of EBV-associated diseases. Non-LPD that have significant percentages of cases associated with EBV infection (see Epstein–Barr virus infection) include the immune disorders of multiple sclerosis and systemic lupus erythematosus; malignancies such as stomach cancers, soft tissue sarcomas, leiomyosarcoma, and undifferentiated nasopharyngeal cancer; the childhood disorders of Alice in Wonderland syndrome; and acute cerebellar ataxia.