is an indolent (slow-growing) cancer
in which too many immature lymphocytes (white blood cells) are found mostly in the blood and bone marrow
and lymph glands .
Watchful waiting is majority done until any indication present to start treatment. However, there is subtype of cll which behaves more agressively and requires treatment to be started earlier. See more at : www.Lls.Org, www.Cancer.Gov.