Hairy cell leukemia: new understanding of biology and treatment

Secondary acute myeloid leukemia 4 years after the diagnosis of hairy cell leukemia: case report and review of the literature

A 49-year-old man diagnosed with hairy cell leukemia (HCL) achieved a complete remission lasting 4 years after treatment with cladrabine and subsequently developed acute myeloid leukemia. Although a wide variety of second malignancies have been noted in HCL with an incidence of 8.7%, acute myeloid leukemia (AML) has been reported only once previously in a splenectomized patient who had been treated with alpha interferon.

The simultaneous occurrence of variant hairy cell leukemia and chronic-phase chronic myelogenous leukemia. A case report

BACKGROUND

Coexistence of second malignancies in patients with hairy cell leukemia is not uncommon. Most second malignancies are solid tumors or other lymphoproliferative proliferative disorders. In this study, a case of a tartrate-resistant acid phosphatase (TRAP)-positive hairy cell leukemia variant with the subsequent development of Philadelphia chromosome-positive chronic myelogenous leukemia (CML) is reported.

METHODS

Routine morphology was performed on the peripheral blood, bone marrow and spleen. Peripheral smears were stained for TRAP. Peripheral blood was studied by two-color flow cytometry for a panel of lymphocytic markers including CD11, CD25, and CD103. Cytogenetic studies were performed on a bone marrow aspirate.

RESULTS

A unique case of a hairy cell leukemia variant and CML in a patient who responded to the new purine analog 2-chlorodeoxyadenosine (2-CdA) is presented.

CONCLUSIONS

The first case of concurrent hairy cell leukemia with CML is reported.

Clinical and toxicological aspects of the antineoplastic drug cladribine: a review

Cladribine (2-chlorodeoxyadenosine, 2-CdA) is a new antineoplastic drug which exerts its antilymphoproliferative activity by its resistance to the enzyme adenosine deaminase. Cladribine is mostly administered as a 7-day continuous infusion and in a dose of 0.1 mg/kg/day. However, preliminary data show that the subcutaneous and oral routes of administration might be feasible. The drug is well tolerated, and myelosuppression was found to be the dose-limiting toxicity. Nonhematological toxicity, such as alopecia, nausea, vomiting, stomatitis, diarrhea, and organ toxicity is mild or absent. Cladribine has shown efficacy in phase-II studies in hairy cell leukemia [response rate (RR) = 75-100% and complete response rate (CR) = 46-92%], chronic lymphocytic leukemia (RR = 37-67% and CR = 4-39%), and lymphocytic lymphoma (RR = 43-52% and CR = 14-20%). Furthermore, there is preliminary evidence that cladribine might be effective in the treatment of cutaneous T cell lymphoma (RR = 47% and CR = 20%), acute myeloid leukemia in children (RR = 59% and CR = 47%), acute lymphoid leukemia in children (RR = 14% and CR = 14%) and Waldenström macroglobulinemia (RR = 58% and CR = 3.5%). In multiple myeloma cladribine was not effective. Comparative randomized studies with established first-line and second-line therapeutic regimens are warranted and will define the ultimate place of cladribine in the therapy of malignant hematological disorders.