Gene mutations and treatment outcome in chronic lymphocytic leukemia: results from the CLL8 trial

Abstract

Key Points• Independent prognostic impact of biological markers, notably TP53 and SF3B1 mutations, in CLL patients requiring therapy.• NOTCH1 mutation as a predictive factor for reduced benefit from the addition of rituximab to FC chemotherapy.Mutations in TP53, NOTCH1, and SF3B1 were analyzed in the CLL8 study evaluating firstline therapy with fludarabine and cyclophosphamide (FC) or FC with rituximab (FCR) among patients with untreated chronic lymphocytic leukemia (CLL). TP53, NOTCH1, and SF3B1 were mutated in 11.5%, 10.0%, and 18.4% of patients, respectively. NOTCH1 mut and SF3B1 mut virtually showed mutual exclusivity (0.6% concurrence), but TP53 mut was frequently found in NOTCH1 mut (16.1%) and in SF3B1 mut (14.0%) patients. There were few significant associations with clinical and laboratory characteristics, but genetic markers had a strong influence on response and survival. In multivariable analyses, an independent prognostic impact was found for FCR, thymidine kinase (TK) ‡10 U/L, unmutated IGHV, 11q deletion, 17p deletion, TP53 mut , and SF3B1 mut on progression-free survival; and for FCR, age ‡65 years, Eastern Cooperative Oncology Group performance status ‡1, b2-microglobulin ‡3.5 mg/L, TK ‡10 U/L, unmutated IGHV, 17p deletion, and TP53 mut on overall survival. Notably, predictive marker analysis identified an interaction of NOTCH1 mutational status and treatment in that rituximab failed to improve response and survival in patients with NOTCH1 mut . In conclusion, TP53 and SF3B1 mutations appear among the strongest prognostic markers in CLL patients receiving current-standard first-line therapy. NOTCH1 mut was identified as a predictive marker for decreased benefit from the addition of rituximab to FC. This study is registered at www.clinicaltrials.gov as #NCT00281918. (Blood. 2014;123(21):3247-3254)

Chlorambucil plus rituximab with or without maintenance rituximab as first‐line treatment for elderly chronic lymphocytic leukemia patients

“…Neither NOTCH1, SF3B1, or BIRC3 mutations impacted on OR after induction, in line with other reports [33,34]; however, SF3B1 mutations and BIRC3 disruption were rarely detected in CR patients.…”

EGR2 mutations define a new clinically aggressive subgroup of chronic lymphocytic leukemia

“…CHD2 15 , MED12 16 , NFKBIE 17 , POT1 18 , RPS15 19 , SETD2 20 , XPO1 21 ). Though integration of molecular information has been proposed to improve classical risk stratification models [22][23][24][25] , a substantial proportion of patients with a dismal clinical course will not be captured by these algorithms, hence indicating a need to identify additional molecular markers of disease aggressiveness.…”

Common nonmutationalNOTCH1activation in chronic lymphocytic leukemia

“…NOTCH1 mutations in CLL were shown to associate with poor prognosis, including a specific subset of patients carrying trisomy 12, disease progression, transformation to highly aggressive diffuse large B-cell lymphomas, termed Richter syndrome, and immunochemotherapy resistance (3,4,(12)(13)(14)(15)(16).…”