title: Rituximab and risk of second primary malignancies in patients with non-Hodgkin lymphoma: a systematic review and meta-analysis.
abstract: BACKGROUND
  Addition of the anti-CD20 monoclonal antibody rituximab to chemotherapy improves response rates and survival in patients with B-cell non-Hodgkin lymphoma (NHL). However, rituximab induces a transient B-cell depletion and a dose-dependent T-cell inactivation that could impair T-cell immunosurveillance. The impact of rituximab on second primary malignancy (SPM) risk remains unclear so far. We thus carried out a systematic review to compare SPM risk among patients treated or not with rituximab.
  
  
  METHODS
  We retrieved trials from MEDLINE and EMBASE and updated data presented at American Society of Hematology and American Society of Clinical Oncology meetings from 1998 to 2013. We selected randomized, controlled trials addressing newly or relapsed/progressive B-cell NHL in which randomization arms differed only from rituximab administration. Two authors extracted data and assessed the study quality.
  
  
  RESULTS
  We analyzed nine trials involving 4621 patients. At a median follow-up of 73 months, a total of 169 SPMs were observed in patients randomized to rituximab compared with 165 SPMs in patients not randomized to rituximab (OR = 0.88; 95% CI 0.66-1.19). The proportion of females, histology subtypes, use of rituximab in first line or in maintenance did not influence SPM risk (P = 0.94, P = 0.80, P = 0.87, P = 0.87, respectively). Cumulative exposure through prolonged administration in trials with rituximab maintenance did not contribute to an increased risk of SPM (P = 0.86).
  
  
  CONCLUSIONS
  Our meta-analysis suggests no SPM predisposition among NHL survivors exposed to rituximab at a median follow-up of 6 years.
authors.affiliation: Departments of Hemato-oncology, APHP, Saint-Louis hospital, Paris.
authors.forename: I
authors.initials: I
authors.lastname: Fleury
authors.affiliation: Biostatistics, APHP, Saint-Louis hospital, Paris ECSTRA Team, UMR 1153, Inserm Paris Diderot University Paris, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Chevret
authors.affiliation: Internal Medicine, Universitätsklinikum des Saarlandes, Homburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Pfreundschuh
authors.affiliation: Hospices civils de Lyon, Pierre-Bénite, France.
authors.forename: G
authors.initials: G
authors.lastname: Salles
authors.affiliation: Hospices civils de Lyon, Pierre-Bénite, France.
authors.forename: B
authors.initials: B
authors.lastname: Coiffier
authors.affiliation: Department of Hematology, Academisch Medisch Centrum, Amsterdam, The Netherlands.
authors.forename: M H J
authors.initials: MH
authors.lastname: van Oers
authors.affiliation: Departments of Hemato-oncology, APHP, Saint-Louis hospital, Paris.
authors.forename: C
authors.initials: C
authors.lastname: Gisselbrecht
authors.affiliation: Oncology Institute of Southern Switzerland, IOSI, Ospedale San Giovanni, Bellinzona Swiss Group for Clinical Cancer Research-SAKK, Berne, Switzerland.
authors.forename: E
authors.initials: E
authors.lastname: Zucca
authors.affiliation: Onkologisches Zentrum, HELIOS Klinikum, Erfurt, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Herold
authors.affiliation: Oncology Institute of Southern Switzerland, IOSI, Ospedale San Giovanni, Bellinzona Swiss Group for Clinical Cancer Research-SAKK, Berne, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Ghielmini
authors.affiliation: Departments of Hemato-oncology, APHP, Saint-Louis hospital, Paris Paris Diderot University, Sorbonne Paris Cité, Paris, France catherine.thieblemont@sls.aphp.fr.
authors.forename: C
authors.initials: C
authors.lastname: Thieblemont
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007165:Immunosuppression Therapy; D008228:Lymphoma, Non-Hodgkin / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000139:chemically induced*; D000069283:Rituximab / Q000009:adverse effects* / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D000069283:Rituximab
keywords: meta-analysis; non-Hodgkin lymphoma; randomized controlled trials; rituximab; second primary malignancies; secondary cancers