[Morphological and immunohistochemical characteristics of primary brain lymphomas in AIDS patients]

Primary lymphomas of the brain were studied in 6 AIDS patients. The lymphomas were characterized by multicentricity, extended necroses and location in large hemispheres. Two types of tumor cell growth were recorded: diffuse and perivascular with vascular wall destruction. According to the International Histologic Classification (2001), these lymphomas were classified as diffuse B-cell large cell lymphomas subdivided into 3 variants: immunoblastic with plasma cell differentiation, centroblastic polymorphic and large cell anaplastic (by Kils classification criteria). Immunohistochemically (LMP-1) and by hybridization in situ (RNA EBER-1,2) Epstein-Barr virus was found in tumor cells from all the patients. In 5 of 6 cases studied expression of the antiapoptotic protein bcl-2 and in 2 cases expression of mutant p53 were revealed.