Reduced hematologic response to alpha-interferon therapy in patients with hairy cell leukemia showing a peculiar
1Istituto di Ematologia L.e A. Seràgnoli, University of Bologna, Italy.
Insights
Hairy cell leukemia (HCL) patients with a specific CD5 marker on leukemia cells show poor response to alpha-interferon (alpha-IFN) therapy. This immunologic marker may predict treatment outcomes in HCL.
Area of Science:
- Hematology
- Immunology
- Oncology
Background:
- Alpha-interferon (alpha-IFN) is effective for hairy cell leukemia (HCL) but complete remissions are rare.
- Some HCL patients exhibit inadequate responses to alpha-IFN treatment.
Purpose of the Study:
- To investigate if a specific immunologic surface marker profile of hairy cells (HC) correlates with poor alpha-IFN response in HCL patients.
Main Methods:
- Analysis of immunologic surface marker profiles using monoclonal antibodies, specifically Leu1 (CD5).
- Comparison of treatment responses (CR, PR, MR) between HCL patients with and without the Leu1 (CD5) marker.
Main Results:
- HCL patients with a Leu1 (CD5)-positive phenotype showed significantly poorer responses to alpha-IFN.
- Of nine Leu1 (CD5)-positive HCL patients, only three achieved partial remission (PR), and six had minor responses (MR).
- In contrast, 22 Leu1 (CD5)-negative HCL patients achieved three complete remissions (CR), 16 PR, and three MR.
Conclusions:
- The presence of the Leu1 (CD5) marker on hairy cells may indicate a poor prognosis and reduced response to alpha-IFN therapy.
- Extensive immunologic analysis at diagnosis could predict alpha-IFN treatment efficacy in HCL.
Abstract:
Alpha-interferon (alpha-IFN) treatment is highly effective in normalizing the clinical, hematologic, and immunologic parameters of patients with hairy cell leukemia (HCL). Complete remissions (CR), however, are rare, and a few patients do not respond adequately to alpha-IFN. That the poor response to alpha-IFN treatment could be related to a particular immunologic surface marker profile of the HC was investigated in this study. The results showed that most patients who do not respond adequately to alpha-IFN HC have a peculiar immunologic phenotype with a positive response to the Leu1 (CD5) monoclonal antibody, usually absent on HC but characteristically expressed on B-chronic lymphocytic leukemia cells. Of nine HCL patients with this phenotype, only three had partial remissions (PR) and six minor responses (MR) compared with the three CR, 16 PR, and three MR observed in the 22 Leu1 (CD5)-negative patients. The authors postulate that a more extensive immunologic analysis of HCL patients at diagnosis may be predictive of the response to IFN treatment.
