To the Editor: T-cell prolymphocytic leukemia (T-PLL) is the most frequent mature T-cell leukemia in Western countries. Its inherently aggressive growth and a notoriously chemotherapy refractory behavior result in overall survival times of <20–36 months [1, 2]. There are no formally licensed drugs for T-PLL. Although the anti-CD52 monoclonal antibody alemtuzumab induces high primary response rates, the vast majority of patients relapse on average within 12 months thereafter [3, 4].
