The Binet and Rai staging systems are two clinical tools that are used to define the stage of CLL based solely on physical examination and blood counts (Table 2) (Rai et al., 1975; Binet et al., 1977; Binet et al., 1981). Median survival from diagnosis of CLL varies widely from 18 months to more than 10 years and staging can aid in predicting outcomes (Eichorst et al., 2011).

Table 2. Staging systems for CLL (adapted from Oscier, 2012 and Eichorst, 2011). Please note: These original staging systems are presented alongside more recent outcome data.

Binet Stage Features Median survival


<3 Lymphoid areas*

>10 years


≥3 Lymphoid areas

>8 years


Haemoglobin <10 g/dL
platelet count <100 x 109/L

6.5 years

Rai Stage / risk group Features  

0 / low risk

Lymphocytosis only

>10 years

I / intermediate risk


>8 years

II / intermediate risk

Hepatomegaly or splenomegaly

III / high risk

Lymphocytosis and haemoglobin <11 g/dL

6.5 years

IV / high risk

Lymphocytosis and platelet count <100 x 109/L

*The five lymphoid areas comprise: uni or bilateral cervical, axillary and inguinal lymphoid, hepatomegaly and splenomegaly. 

Staging in Early CLL:

The Rai and Binet staging systems are not sensitive enough to account for the clinical heterogeneity seen in early CLL (Binet stage A; Rai stage 0). Therefore, addition of further clinical and laboratory parameters such as age, gender, lymphocyte count, lymphocyte doubling time (LDT) and serum beta 2 microglobulin (B2M), as well as assessment of biomarkers, can aid in the classification of patients with low, intermediate or high risk of disease progression (Oscier et al., 2012).