BACKGROUND: Although patients with Klinefelter syndrome have elevated risk and incidence rates for several solid cancers, reports on the incidence of hematological malignancies have been equivocal.

CASE REPORT: We report a patient diagnosed with angioimmunoblastic T-cell lymphoma in whom Klinefelter syndrome was newly detected. Moreover, we discuss the development of a variety of lymphomas in patients with Klinefelter syndrome.

CONCLUSIONS: This is the first case describing angioimmunoblastic T-cell lymphoma in a patient with Klinefelter syndrome who was treated with chemotherapy.

Keywords: Immunoblastic Lymphadenopathy - therapy, Biopsy, Klinefelter Syndrome - diagnosis, Lymph Nodes - diagnostic imaging, Lymphoma, T-Cell - therapy, Tomography, X-Ray Computed