Primary effusion lymphoma after heart transplantation: a new entity associated with human herpesvirus-8.

Deep immunosuppression and Epstein-Barr virus (EBV) infection promote the emergence of lymphoproliferative disorders in patients undergoing solid organ transplantation. In the last few years a new herpesvirus, named human herpesvirus-8 (HHV-8), has been identified in Kaposi's sarcoma and primary effusion lymphoma (PEL) developing in AIDS patients. Subsequently, the same viral DNA sequences have been identified in almost all cases of Kaposi's sarcoma emerged outside HIV infection, thus suggesting their possible pathogenetic role in this tumor. Similarly, the association between HHV-8 and PEL also emerged in cases without HIV infection, even though the total number of these patients is still limited. Here, we focus on the emergence of this unusual lymphoma in patients undergoing solid organ transplant and underline once again its association with the HHV-8. Moreover, despite the characteristic local growth of this peculiar type of lymphoma, we demonstrate at the molecular level, an early neoplastic spread to the bone marrow suggesting the need to investigate in more detail the origin of the disease, as well as the molecular mechanisms controlling its systemic dissemination.

Mitotic recombination among acrocentric chromosomes' short arms.

Routine Q-banding chromosome analysis detected the jumping behaviour of bright fluorescent chromosome 22 satellites (22s+) in two unrelated males (case 1 ascertained for recurrent abortions and case 2 for infertility), and in the mother of one of them, all with a normal karyotype. The 22s+ was present in more than 90% of the cells. In a minority of the cells the polymorphism was present alternatively on another acrocentric, on one chromosome 22 and on another acrocentric, on both chromosomes 22 or it was absent. We take these findings as evidence of mitotic exchanges between the short arms of the acrocentric chromosomes. The presence of a stable 22s+ in the fibroblasts of case 1 and in the lymphocytes of his son indicates that acrocentric short arm exchanges depend both on the type of tissue and on the genetic content of all the other acrocentrics.