A new score including CD43 and CD180: Increased diagnostic value for atypical chronic lymphocytic leukemia

Area of Science:

• Hematology
• Immunophenotyping
• Diagnostic Biomarkers

Background:

• The Moreau score is used to distinguish chronic lymphocytic leukemia (CLL) from other mature B-cell neoplasms.
• The Moreau score has demonstrated limitations, particularly in Asian patient populations.
• A need exists for a more accurate diagnostic tool for CLL, especially in diverse ethnic groups.

Purpose of the Study:

• To develop and evaluate a novel scoring system for the diagnosis of CLL.
• To replace CD5 and CD23 with CD43 and CD180 in the diagnostic criteria for CLL.
• To assess the diagnostic performance of the new score in differentiating CLL from other mature B-cell neoplasms, particularly in Asian patients.

Main Methods:

• Collected 237 untreated mature B-cell neoplasm samples, divided into exploratory (2:1 ratio) and validation cohorts.
• Analyzed the expression of CD5, CD19, CD20, CD23, CD43, CD79b, CD180, CD200, FMC7, and surface immunoglobulin (SmIg).
• Developed a new CLL score using a logistic regression model and evaluated its sensitivity and specificity via ROC curves.

Main Results:

• The new CLL score, incorporating CD43/CD180, CD200, FMC7, and CD79b, achieved 91.8% sensitivity and 83.1% specificity in the exploratory cohort.
• Validation cohort confirmed the score's performance with 90.5% sensitivity and 79.5% specificity.
• The new score demonstrated significantly improved sensitivity (79.4%) in CD5/CD23 negative and atypical CLL cases compared to Moreau and CLLflow scores.

Conclusions:

• The proposed CLL score, utilizing CD43 and CD180, offers improved diagnostic accuracy for CLL.
• This novel score is particularly valuable for differentiating CLL in cases with atypical immunophenotypes and in Asian populations.
• The new scoring system, combined with morphological and molecular methods, enhances the accurate diagnosis of CLL.