[Primary Ki-1 positive anaplastic large cell non-Hodgkin's lymphoma of the lung. A case study and review of the literature].

Ki-l positive anaplastic large cell non-Hodgkin's lymphomas are a recently recognized entity, unusual and characterized by the expression of CD30 antigen. The most usual clinical feature is peripheral lymphadenopathy with mediastinal sparing and extranodal disease which occurs in approximately half of the cases, with the skin as the most common site; lung, bone marrow and central nervous system involvement are uncommon. Therefore primary pulmonary Ki-l positive anaplastic large cell non-Hodgkin's lymphomas are an uncommon clinical entity. Their classification and clinical behaviour look like high grade malignancy lymphomas, that in the most cases are presented in advanced stages disease to the diagnostic. They are presented with higher incidence in young people, where prognostic is more favourable. Clinical, morphologic and inmunophenotypic features of this lymphoma type are reported.