Improved Survival with Radiotherapy in Stage I-II Primary Mediastinal B-Cell Lymphoma: A Surveillance, Epidemiology, and End Results Database Analysis
Menée à partir des données des registres américains des cancers portant sur 250 patients atteints d'un lymphome primitif médiastinal à grandes cellules B de stade I/II diagnostiqué entre 2001 et 2011 (âge médian : 36 ans ; durée médiane de suivi : 39 mois), cette étude montre que l'utilisation de la radiothérapie améliore la survie des patients
Background : Primary mediastinal B-cell lymphoma (PMBCL) is an uncommon lymphoma for which trials are few with small patient numbers. The role of radiotherapy (RT) following standard immunochemotherapy for early stage disease has never been studied prospectively. We utilized the Surveillance, Epidemiology, and End Results (SEER) database to evaluate PMBCL and the impact of RT on outcomes. Materials/Methods : We queried the SEER database for patients with Stage I/II PMBCL diagnosed from 2001-2011. Retrievable data included age, gender, race (white/nonwhite), stage, extra-nodal (E) disease, year of diagnosis, and use of RT as a component of definitive therapy. Kaplan-Meier overall survival estimates, univariate (UVA) log rank and multivariate (MVA) Cox proportional hazards regression analyses were performed. Results : 250 stage I/II patients were identified with a median follow-up of 39 months (range 3 - 125). Median age was 36 years (range 18-89); 61% were female, 76% white, 45% stage I, 60% with E disease, and 55% given RT. 5-year OS for the entire cohort was 86%. On UVA OS was improved with RT (HR 0.446, p=0.029) and decreased in association with non-white race (HR 2.70, p=0.006). 5-year OS was 79% (no-RT) and 90% (RT). On MVA, white race and RT remained significantly associated with improved OS (p=0.007 and 0.018, respectively). Use of RT decreased over time: 61% for the 67 patients diagnosed from 2001-05 and 53% in the 138 patients treated from 2006-10. Conclusion : This retrospective population-based analysis is the largest PMBCL dataset to date and demonstrates a significant survival benefit associated with RT. Nearly half of patients treated in the United States do not receive RT, and its use appears to be declining. In the absence of phase III data, use of RT should be strongly considered for its survival benefit in early stage disease.
http://www.redjournal.org/article/S0360-3016%2815%2903347-7/abstract