Patients who have chronic lymphocytic leukemia and achieve minimal residual disease negativity have a high probability of long-term progression-free and overall survival, irrespective of the type of therapy they receive, reported Marwan Kwok, MD, of Queen Elizabeth Hospital Birmingham (England) and colleagues.

Minimal residual disease (MRD) negativity, defined as less than 1 chronic lymphocytic leukemic (CLL) cell detectable per 10,000 leukocytes, has been shown to independently predict clinical outcome in the front line setting, but the long-term prognostic value of MRD status in other therapeutic settings remains unclear. “Our results demonstrate the long-term benefit of achieving MRD negativity regardless of the therapeutic setting and treatment modality, and support its use as a prognostic marker for long-term PFS (progression-free survival) and as a potential therapeutic goal in CLL,” the authors wrote (Blood. 2016 Oct 3. doi: 10.1182/blood-2016-05-714162).

The researchers retrospectively analyzed, with up to 18 years of follow-up, all 133 CLL patients at St. James’s University Hospital in Leeds, England, who achieved at least a partial response with various therapies between 1996 and 2007 and who received a bone marrow MRD assessment at the end of treatment, according to the international harmonized approach.

MRD negativity correlated with progression-free and overall survival, and the association was independent of the type and line of treatment, as well as adverse cytogenetic findings, the investigators said.

For those who achieved MRD negativity in front-line treatment, the 10-year progression-free survival was 65%; survival in patients who did not achieve MRD negativity was 10%. Overall survival at 10 years was 70% for those who achieved MRD negativity and 30% for MRD-positive patients.

The authors had no relevant financial disclosures.