The role of radiotherapy and intrathecal CNS prophylaxis in extralymphatic craniofacial aggressive B-cell lymphomas
Menée à partir des données de 11 essais incluant au total 4 155 patients atteints d'un lymphome agressif à cellules B dont 290 présentant un envahissement extra-lymphatique crânio-facial, cette étude évalue l'intérêt d'une radiothérapie et d'une prophylaxie intrathécale par méthotrexate pour réduire le risque d'envahissement du système nerveux central
To define the role of radiotherapy and intrathecal prophylaxis in extralymphatic craniofacial involvement (ECFI) of aggressive B-cell lymphoma we analyzed 11 consecutive DSHNHL trials. ECFI occurred in 290/4155 (7.0%) patients (orbita: 31, paranasal sinuses: 93; main nasal cavity: 38, tongue: 27, remaining oral cavity: 99, salivary glands: 54). In a multivariable analysis adjusted for IPI rituximab improved EFS and OS both in patients with and without ECFI. Three-year event-free (79% vs 79%; p=0.842) and overall survival (86% vs. 88%; p=0.351) were similar in 145 patients receiving and 57 not receiving radiotherapy. Without rituximab, the 2-year cumulative rate of CNS disease was increased in 205 ECFI patients compared to 2586 non-ECFI patients (4.2% vs. 2.8%; p=0.038), while this was not observed with rituximab (1.6% in 83 ECFI vs 3.4% in 1252 non-ECFI patients; p=0.682). In 88 ECFI patients who received intrathecal prophylaxis with methotrexate, 2-year rate of CNS disease was 4.2% compared to 2.3% in 191 patients who did not (p=0.981). In conclusion, rituximab eliminates the increased risk for CNS disease in patients with ECFI. This retrospective analysis does not support intrathecal prophylaxis or radiotherapy to ECFI patients in CR/CRu. These findings should be confirmed in a prospective study.