CD38 expression as a prognostic indicator in chronic lymphocytic leukaemia

Area of Science:

• Hematology
• Oncology
• Immunology

Background:

• Chronic lymphocytic leukemia (CLL) staging systems predict survival but not disease progression.
• CD38 expression is an established prognostic factor in CLL, but optimal thresholds remain debated.

Purpose of the Study:

• To determine the most effective CD38 expression threshold for predicting treatment-free interval (TFI) in CLL patients.
• To correlate CD38 expression levels with clinical stage, sex, and genetic abnormalities.

Main Methods:

• Hazard ratios for TFI were calculated across CD38 expression cut-offs from 0% to 100%.
• Triple-color flow cytometry analyzed CD38 expression in 289 untreated CLL patients.
• Correlation with clinical stage, sex, and genetic markers (p53, 13q14, 11q23 deletions, trisomy 12) was assessed.

Main Results:

• A CD38 cut-off of 7% maximized the hazard ratio for TFI.
• Patients with <7% CD38 expression had a significantly longer TFI (median 36 months) compared to those with ≥30% (8.7 months) or intermediate levels.
• The <7% threshold correlated with early-stage disease (Stage A) and a longer TFI, and was associated with 13q14 deletion.
• Higher CD38 expression (≥7% or ≥30%) showed a tendency towards trisomy 12.

Conclusions:

• A 7% CD38 expression threshold is a more sensitive indicator of CLL disease progression and TFI than higher thresholds.
• CD38 expression, particularly at the 7% threshold, holds independent prognostic value for TFI in CLL.
• This finding aids in refining prognostic assessments and potentially guiding treatment decisions in CLL.