Sixty-three patients with T-cell lymphoma (TCL) were analyzed to correlate morphological and immunological features with clinical presentation, response to therapy, and survival. Clinical presentation was severe, with 59% of patients having stage IV disease, 60% B symptoms, 35% poor performance status, 44% large tumoral mass, and 40% a high number of extranodal localizations. Morphological subtypes were small-cell in four cases, diffuse-mixed in 29 cases, monomorphic medium-sized in two cases, immunoblastic in 21 cases, anaplastic large-cell in four cases, and unclassified in three cases. Immunological phenotypes were immature T in 11 cases, CD4 in 26 cases, CD8 in 13 cases, and undefined (CD4 + CD8) in ten cases. Response to therapy was poor except for the 39 patients treated by an intensive and sequential regimen (non-Hodgkin's lymphoma [LNH]-80 or LNH-84) that gave a 77% complete remission (CR) rate with a 23% relapse rate. Median survival was 35 months. No correlation was found between morphological subtypes and other variables. Helper (CD4) phenotype seemed to have a better prognosis than other phenotypes. Variables associated with long survival for all the patients were localized disease and absence of large tumoral mass and for the subgroup of patients treated by the LNH regimens CD4 phenotype, absence of B symptoms, absence of a large tumoral mass, and less than two extranodal sites of disease.