Page 855 - Hematology_ Basic Principles and Practice ( PDFDrive )

738 Part VI Non-Malignant Leukocytes

years in some centers. These two approaches appear to have unique Disease manifestations can subside over several months to years.
strengths and weaknesses. Although a significant number of patients Of 215 cases in a patient registry, 21% had complete resolution of
fail to respond adequately or completely to etoposide-based regimens, disease. However, 14 patients died. Five died of “immunologic”
ATG-based regimens are complicated by relatively frequent and early causes, such as severe hemolysis; three died of infections; and six
relapse (median time to relapse reported by Ouachee-Chardin et al, probably died as a direct consequence of disease infiltration. As the
5.5 weeks). Thus, a rational combination of these approaches may disease resolves, extranodal disease regresses before nodal disease.
improve outcomes by increasing initial responses and maintaining Corticosteroids, vinblastine, and low-dose cyclophosphamide are
them until HCT can be obtained. Currently, a multicenter clinical sometimes effective; however, the results with these agents have been
trial called hybrid immunotherapy for HLH (HIT-HLH) is underway inconsistent. A recent report has found that (similar to refractory
in North America, testing the potential of this idea. A sister trial is LCH) clofarabine may be a highly active agent in patients with
being conducted in Europe. In this approach, ATG and etoposide are SHML who require systemic therapy. Attempts at treatment should
incorporated into one regimen, but the etoposide dose intensity is be reserved for special circumstances, such as tracheal or epidural
decreased to minimize potential myelosuppression. No data are avail- compression, or invasion of other vital structures, as well as for sig-
able yet regarding the usefulness of this approach. Alternative strate- nificant cosmetic disfigurement. Local excision may be useful in
gies using anticytokine antibodies for induction therapy are also being selected patients, although the lesions may reappear.
developed.
Although HLH appears to be a disease of excessive immune
activation, the ideal form of immune suppression and antiinflamma- SUGGESTED READINGS
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