Radiation therapy for the management of patients with HTLV-1–associated adult T-cell leukemia/lymphoma

Abstract
Human T-cell leukemia virus type 1–associated adult T-cell leukemia/lymphoma (ATL) typically has survivals measured in months with chemotherapy. One prior published series (1983-1991) assessed local radiotherapy for ATL. Ten consecutive patients with pathologically confirmed ATL treated with radiotherapy were reviewed. Subtypes included acute (n = 7), smoldering (n = 2), and lymphomatous (n = 1). Patients received an average of 2.5 systemic therapy regimens before radiotherapy. Twenty lesions (cutaneous = 10, nodal = 8, extranodal = 2) were treated to a mean of 35.4 Gy/2-3 Gy (range, 12-60 Gy). At 9.0-month mean follow-up (range, 0.1-42.0 months), all lesions symptomatically and radiographically responded, with in-field complete responses in 40.0% (nodal 37.5% vs cutaneous 50.0%; P = .62). No patient experienced in-field progression. Nine patients developed new/progressive out-of-field disease. Median survival was 17.0 months (3-year survival, 30.0%). No Radiation Therapy Oncology Group acute grade ≥ 3 or any late toxicity was noted. This report is the first to use modern radiotherapy techniques and finds effective local control across ATL subtypes. Radiotherapy should be considered for symptomatic local progression of ATL.