Effective treatment of a refractory hairy cell leukemia variant with splenic pre-irradiation and alemtuzumab

A 72-year-old Japanese man presented with 43.1 x 10(9)/l hairy cells and apparent splenomegaly. The leukemia cells had unevenly distributed microvilli and round nuclei with dense chromatin and one or two clear nucleoli, lacked CD25 expression and were negative for tartrate-resistant acid phosphatase. The case was diagnosed as hairy cell leukemia variant (HCLv) and proved refractory to various chemotherapies, including cladribine, pentostatin, interferon-alpha, CHOP and rituximab. Because of the CD52 expression, we treated the patient with alemtuzumab. Pretreatment with 22.5 Gy to the spleen reduced the spleen size from 12 to 4 cm below the left costal margin, and the number of circulating leukemic cells decreased from 229.0 to 63.6 x 10(9)/l. Subsequent administration of 24.0 mg of alemtuzumab eliminated leukemic cells in the peripheral blood on day 12, and the spleen was not palpable after the administration of 54.0 mg of alemtuzumab. In vitro treatment with alemtuzumab confirmed the cytotoxic effect against the patient's leukemic cells in the presence of complement. This is the first report showing clinical effectiveness of splenic irradiation and alemtuzumab against refractory HCLv.

Advances in the treatment of hairy-cell leukaemia

Hairy-cell leukaemia (HCL) is an uncommon B-cell chronic lymphoproliferative disorder that accounts for about 2% of all leukaemias. Although the disease is generally indolent in its natural course, the majority of patients require treatment for life-threatening infections due to pancytopenia or symptomatic splenomegaly. During the past 20 years, remarkable progress has been made in the treatment of HCL. Since the introduction of interferon-alpha, splenectomy, which was formerly the standard therapy, has been rarely used. With the purine analogues cladribine and pentostatin, response rates are even better than with interferon-alpha and long-lasting remissions can be achieved in most patients. Therefore, these agents are now considered the treatment of choice. Recently, immunotherapeutic approaches which use monoclonal antibodies have increased the number of therapeutic options for HCL and offer promising salvage strategies for patients who relapse or who are refractory to treatment with purine analogues. In this review the different treatment options available are discussed and recommendations for the clinical management of the HCL are summarised.

Clinical indications and biological mechanisms of splenic irradiation in chronic leukaemias and myeloproliferative disorders

Splenic irradiation (SI) was the first efficient treatment for chronic leukaemia, but with the emergence of effective drugs its use has been more and more restricted to advanced cases presenting with splenomegaly. But in selected patients who are not responsive or not suitable to drug treatment, SI may offer still an effective, low toxic and cost-effective palliative modality. Eight studies of SI in chronic lymphatic leukaemia (CLL) including 198 patients, six reports about SI in prolymphocytic leukaemia (PLL), including 18 patients, one study and six case reports about SI in hairy cell leukaemia (HCL) and nine studies about SI in myeloproliferative disorders has been analyzed. In CLL, symptoms of splenomegaly have been improved in 50-87% of all patients with overall doses between 4 and 10 Gy in mostly 1-Gy fractions. PLL seems to be more resistant to SI with a median response rate of 66%. Casuistic reports described also efficacy of SI in HCL patients using similar radiation schedules. Symptomatic relief is also provided by SI in myeloproliferative disorders using lower overall doses between 1 and 9 Gy with small single fractions of 0.25 Gy (median). Acute toxicity was low in lymphoid disorders, but higher in myeloproliferative disorders with severe cytopenia in 10-30% of all cases, indicating the need for a cautious fractionation schedule. Interestingly, even complete systemic remissions after SI in all types of lymphoproliferative disorders have been described. Different mechanisms underlying SI such as direct cell kill, immune modulation via changes in lymphocyte subsets or cytokine induction or "radiotherapeutic" splenectomy with high doses are discussed.

Splenic irradiation for hairy cell leukaemia

Splenic irradiation in the management of hairy cell leukaemia is previously unreported. A case is presented here to illustrate that splenic irradiation may be a useful addition to systemic therapies.

Remission in hairy cell leukemia-variant following splenic radiotherapy alone

The therapeutic approach to hairy cell leukemia (HCL) is in some instances still debated. A variant form of HCL (HCL-V) characterized by high white cell count, splenomegaly, hypercellular and aspirable bone marrow has been described; differential diagnosis often arises with some other B-cell disorders which also show circulating hairy or villous lymphocytes. Conventional treatment for HCL is often less effective in HCL-V. In this report we describe a case with features consistent with HCL-variant treated with splenic radiotherapy. We not only obtained an hematological response but also the near total disappearance of bone marrow infiltration, compatible with a clinical complete remission. Clinical and biological implications of this phenomenon are discussed on the basis of this unexpected therapeutic result, obtained with splenic radiotherapy alone.

Hairy cell leukemia. A therapeutical update

This is a review of current treatment for hairy cell leukemia (HCL). Data for this analysis were obtained from the Italian HCL Registry, as well as from other published series. We have given space to the impact of interferon and pentostatin on the management of this disease. Other issues are also discussed, such as the relevance of achieving a complete remission with respect to overall and relapse-free survival. We include a final section on recommendations which may prove useful in designing an appropriate therapeutic strategy.

A role for splenic irradiation in the treatment of hairy-cell leukaemia. Case report and review of the literature

The use of splenic radiotherapy in the treatment of hairy-cell leukaemia is discussed. Reference is made to the case of an elderly female whose cardiorespiratory state precluded splenectomy, and who responded well to splenic irradiation on two occasions.

Bone involvement in hairy-cell leukemia

Destructive bone involvement is a rarely recognized complication of hairy-cell leukemia (leukemic reticuloendotheliosis). We report a case in which localized hip pain and lytic bone lesions were the presenting manifestations. A second case of bone involvement in a patient with previously diagnosed hairy-cell leukemia is also described. These cases are compared with the nine cases of hairy-cell leukemia with bone involvement previously published in the medical literature.

A role for radiation in the treatment of hairy cell leukemia complicated by massive lymphadenopathy: a case report

A patient with leukemic reticuloendotheliosis is described who two years following splenectomy developed massive retroperitoneal, abdominal, and mediastinal lymphadenopathy. Therapeutic intervention was necessary because the bulky tumor masses produced disabling pain in the back and chest regions. Low-dose radiation to the involved fields produced prompt regression of the adenopathy along with dramatic pain relief. This case suggests that hairy cells may be quite sensitive to radiation, and this therapeutic modality should be considered, especially when local problems are present.