Correlation of clinical responses with immunologic and morphologic characteristics in patients with cutaneous T-cell lymphoma treated with interferon alfa-2a

Background: Immunophenotyping may aid in distinguishing more aggressive forms of cutaneous T-cell lymphoma (CTCL), thereby improving classification and treatment. Objective: Our purpose was to investigate the relations between clinical, histologic, and im-munophenotypic profiles in determining variables with respect to outcome. Methods: Thirty-seven cases of histologically proven CTCL were analyzed in relation to clinical responses to treatment with interferon alfa alone or in combination with PUVA. Clinical stage, immunophenotyping, and histologic features were noted. Results: All patients with no response to therapy had deletion of T-cell CD7 antigen. In contrast, only 21% of patients with a complete response had CD7 deletion. Deletion of the CD5 antigen occurred in 50% of patients with no response and in no patients with complete response. Large cell histologic features were found in 16% of patients with a complete response, 42% with a partial response, and 83% with no response. The presence or absence of other T-cell antigens and the clinical stage of disease did not correlate with outcome. Conclusion: Immunophenotypic analysis may be of greatest value in identifying a subset of high-risk CTCL patients, including those previously classified as low risk on the basis of clinical stage.