This report documents the occurrence of an extranodal cytotoxic peripheral
T-cell lymphoma (PTCL) in a patient with X-linked agammaglobulinaemia (XLA)
. The diagnosis was based on the immunohistochemical detection of T-cell an
tigens and of the cytotoxic proteins TIA1 and Granzyme B in the tumour cell
s. This report provides further evidence that cytotoxic lymphomas are part
of the differential diagnosis of neoplasia in patients with immunodeficienc
ies.