Benign atypical intravascular CD30(+) T-cell proliferation: a reactive condition mimicking intravascular lymphoma.

CD30 is a transmembrane glycoprotein molecule usually expressed in activated B and T cells. Although it has been considered a reliable marker for CD30 lymphomas, reactive inflammatory disorders may contain a significant number of CD30 cells mimicking lymphoproliferative disorders clinically or histologically. Intravascular lymphoma is a rare variant of non-Hodgkin lymphoma that can involve the skin in 40% of the patients. The majority of cases show a B-cell phenotype, and only a minority of cases are of T-cell or NK-cell origin. Moreover, 2 aggressive cases of intravascular large T-cell lymphoma have been described with a CD30 phenotype. Herein, we report 2 patients with skin lesions showing an atypical intravascular CD30 T-cell proliferation. Both the patients did not present systemic disease and therefore exhibit a favorable outcome. To the best of our knowledge, this is the second report in the literature of a benign intravascular CD30 T-cell proliferation that represents an intriguing differential diagnosis for intravascular lymphoma.