Epstein-Barr virus-positive systemic NK/T-cell lymphomas in children: report of six cases

Aims: The World Health Organization lymphoma classification recognizes two different Epstein-Barr virus (EBV)-positive T-cell lymphoproliferative disorders of childhood: systemic EBV-positive T-cell lymphoproliferative disease of childhood, and hydroa vacciniforme-like lymphoma, which is more prevalent in Asia and Latin America. The aim of this study was to characterize six cases of paediatric EBV-positive peripheral T-cell lymphoma with distinct features. Methods and results: All cases were male, with a median patient age of 9 years (range: 5-17 years). Most of them presented suddenly with fever, weight loss, hepatosplenomegaly, peripheral lymphadenopathy, and high lactate dehydrogenase (LDH) levels. Moreover, gut, lung or soft tissues of the abdominal wall were also affected in four cases. Partial to total replacement of the lymph node by pleomorphic infiltration of atypical neoplastic cells was found in all cases. Vasculitis and geographical areas of necrosis were seen in three and four cases, respectively. Neoplastic cells showed expression of EBV-encoded RNA, T-cell markers (CD2 and CD3), and cytotoxic markers (TIA1, granzyme-B, and perforin). CD56 and T-cell receptor -gamma were expressed in one case each. TCRBF1, CD4, CD8 and anaplastic lymphoma kinase were negative. In all cases, the disease progressed rapidly, causing death of the patient, with a median survival of 7.1 months (range: 1-13 months). Conclusions: These cases probably represent a solid form of systemic EBV-positive T-cell lymphoproliferative disease of childhood, which requires identification and the development of appropriate therapy.