The NCCN recommends the use of cytogenetic techniques (conventional karyotyping or FISH) to detect chromosomal abnormalities such as t(11;14), t(11q;v), +12, del(11q), del(13q), del(17p), etc., for the initial diagnosis of chronic lymphocytic leukemia CLL;

Chromosomal abnormalities are present in approximately 80% of CLL patients, and these abnormalities are important for the diagnosis, differential diagnosis, selection of treatment options, and prognosis of CLL;

CLL patients with del(13q) alone have a better prognosis. Chromosomally normal and +12 have a moderate prognosis, while patients with del(11q) or del(17p) have a poor prognosis. In particular, patients with del(17p) have the worst prognosis;

New genetic abnormalities may be acquired during disease progression, and cytogenetic evaluation should be performed again in patients with disease progression, relapse, and drug resistance before starting new therapy;

Patients with therapeutic indications are stratified according to FISH results and different treatment options are selected.