[Allogeneic bone marrow transplantation for chemotherapy-resistant T-prolymphocytic leukemia]

A 34-year-old female was referred to our hospital for the evaluation of atypical lymphocytosis. Leukocyte count at diagnosis was 17,900/microl with 58% atypical lymphocytes having a convoluted nucleus and prominent nucleoli. Because the leukocyte count increased to 43,600/microl, the patient was treated with 2'deoxycoformycin followed by CHOP combination chemotherapy. However, both treatments failed to achieve remission. We planned an allogeneic bone marrow transplantation from an HLA-matched unrelated donor. The patient was treated with Ara-C and etoposide before conditioning to decrease the high leukemia burden. After administration of total body irradiation (12 Gy in six fractions) and cyclophosphamide (total dose of 120 mg/kg) unmanipulated marrow cells were infused. Under prevention of GVHD by CsA and short-term MTX, leukocyte engraft was prompt at day 16, and acute GVHD grade II was observed. Because 9.4% of residual recipient type T-cells was seen with STR analysis on day 22, we decreased the dose of Cs'A. After the occurrence of mild acute GVHD, the residual T-cell number decreased. The patient is still in complete remission for up to 22 months after BMT. We conclude that allogeneic SCT is effective for the treatment of T-PLL.