ATXN1 and adult T-cell leukemia/lymphoma: ATXN1 or CIC alterations are present in 53% of adult T-cell leukemia/lymphoma (ATLL) cases, and CCR4 (C–C chemokine receptor 4) mutations are common, and the majority of ATLL patients exhibit CCR4 overexpression, which is associated with skin involvement and worse prognosis [32].