Intergroup Trial for Children or Adolescents With Primary Mediastinal Large B-Cell Lymphoma: DA-EPOCH-Rituximab Evaluation

Inclusion Criteria:

* Histologically proven Primary Mediastinal Large B-Cell Lymphoma (PMLBL).
* PMLBL without central nervous system (CNS) involvement.
* 6 months to less than 18 years of age at the time of consent.
* Males and females of reproductive potential must agree to use an effective contraceptive method during the treatment, and after the end of treatment: during twelve months for women, taking into account the characteristics of rituximab
* Complete initial work-up within 8 days prior to treatment that allows definite staging.
* Able to comply with scheduled follow-up and with management of toxicity.
* Signed informed consent from patients and/or their parents or legal guardians

Exclusion Criteria:

* Follicular lymphoma, mucosa-associated lymphoid tissue (MALT) and nodular marginal zone
* PMLBL patients with CNS involvement
* Patients with congenital immunodeficiency, chromosomal breakage syndrome, prior organ transplantation, previous malignancy of any type, or known positive HIV serology.
* Evidence of pregnancy or lactation period.
* There will be no exclusion criteria based on organ function.
* Past or current anti-cancer treatment except corticosteroids during less than one week.
* Tumor cell negative for CD20
* Prior exposure to rituximab.
* Severe active viral infection, especially hepatitis B.
* Hepatitis B carrier status history of hepatitis B virus (HBV) or positive serology.
* Participation in another investigational drug clinical trial.
* Patients who, for any reason, are not able to comply with the national legislation.