A further question is whether the newer TKIs prolong survival compared with imatinib for newly diagnosed patients; the most recent data show little difference in progression-free, event-free, or overall survival. Although follow-up to date is substantially shorter than in IRIS, the question remains whether long-term benefits with these agents will outweigh their costs, especially with the prospect of generic imatinib on the horizon.3
Finally, oncologists may have the unprecedented opportunity to consider whether patients with CML are “cured,” in the sense of being able to discontinue therapy. Results of the STIM trial, wherein patients who had maintained CMR for 2 years or longer discontinued imatinib, suggest that some patients may safely do so. However, 61% of patients experienced a molecular relapse and responded again when therapy was reinitiated. Other studies have had similar outcomes.6 Current NCCN guidelines recommend continuing TKI therapy indefinitely.1 Determining which patients can safely stop therapy may be the next milestone in the evolution of CML therapy.
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