RADIOLOGICAL ASSESSMENT OF EXTRANODAL LYM PHOMA - SPECTRUM OF DISEASE

Primary extranodal lymphoma manifestation in the narrow sense is the t erm used to define the primary organ manifestation of a malignant lymp homa, excluding the thymus, spleen, Waldeyer's tonsilar ring, the appe ndix and Peyer's patches. However, in the clinical routine the term is also used for the secondary organ manifestation of underlying lymphop roliferative disease. Primary extranodal lymphomas are mainly non-Hodg kin lymphomas; there is primary extranodal manifestation of Hodgkin's disease in only about 1% of the cases. Among the extranodal NHL, the h ighly malignant forms predominate. A major exception is MALT lymphomas , which mainly show low slow growth. In the past, they were considered to be pseudolymphomas because of their slow and localized tumor growt h. They were included as an entity of their own for the first time in the Revised European American Lymphoma (REAL) classification of 1994. The incidence data vary between <10% and 25% for primary extranodal ma nifestation. The major reason for this is the difference in extranodal regions because of classification. Secondary organ involvment of an N HL occurs in up to 40% of the cases in the long-term course of the dis ease in primary nodal lymphomas. Secondary organ involvment is frequen tly diagnosed in AIDS patients who develop an AIDS-related lymphoma (8 5% of cases). The following contribution reports on the radiological i maging of extranodal lymphoma manifestation in the thoracoabdominal re gion.