Background: Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive T-cell lymphoma and etiologically associated with human T-lymphotropic virus type 1 (HTLV-1). Patients with ATLL commonly present with leukemic changes, systemic lymphadenopathy, and/or extranodal lesion and have very poor prognosis.
Methods and results: We describe a rare case of ATLL presenting as an isolated paranasal mass. Southern blot analysis of the biopsied specimens demonstrated multiple integration bands of HTLV-1 provirus of different intensities. Chemotherapy resulted in complete resolution of the paranasal mass. Thereafter, the patient showed an indolent clinical course with leukemic changes and pulmonary and cutaneous ATLL lesions and remains alive more than 5 years from diagnosis.
Conclusion: ATLL should be included in the differential diagnosis of sinonasal lymphoma, although the event is rare. Multiple HTLV-1 provirus integrations of different intensities may be indicative of good prognosis for ATLL.