Age-related clinical and biological features of PTEN abnormalities in T-cell acute lymphoblastic leukaemia

Archive ouverte

Tesio, M | Trinquand, A. | Ballerini, P | Hypolite, G | Lhermitte, L. | Petit, A. | Ifrah, Norbert | Baruchel, A. | Dombret, H. | Macintyre, E. | Asnafi, V.

Edité par CCSD ; Springer Nature -

International audience. The tumour suppressor gene PTEN is commonly altered in T-cell acute lymphoblastic leukaemia but its prognostic impact is still debated. We screened a cohort of 573 fully characterised adult and paediatric T-cell acute lymphoblastic leukaemia (TALL) patients for genomic PTEN abnormalities. PTEN-inactivating mutations and/or deletions were identified in 91 cases (16%), including 18% of paediatric (49/277) and 14% of adult cases (42/296). Thirty-four patients harboured only mutations, 12 cases demonstrated only large deletions and 9 only microdeletions. About 36 patients had combined alterations. Different mechanisms of PTEN inactivation predicted differences in the clinical outcome for both adult and paediatric patients treated according to the GRAALL03/05 and FRALLE2000 protocols. Whereas large deletions predicted lower 5-year overall survival (P = 0.0053 in adults, P = 0.001 in children) and disease-free survival (P = 0.0009 in adults, P = 0.0002 in children), mutations were not associated with a worse prognosis. The prognostic impact of PTEN loss is therefore linked to the underlying type of genomic abnormality, both in adult and paediatric T-ALLs, demonstrating that detailed analysis of the type of abnormality type would be useful to refine risk stratification.

• Description
• Sujet/Public
• Outil
• Outil d'anticipation
• Mémoire et thèse
• Gestion