CD200 and B-cell chronic lymphocytic leukemia: Additionally, atypical CLL group displayed less intense CD200 expression opposed to classical CLL; as proportion of positive cells ≥ 30% [median 62.6(50.6–84.7%)] vs. [median 98(88.9–100)] and MFIR [median 50.3 (40–57)] vs median 59.8(39.3–69.9)], respectively, p value <0.001.