A Randomized, Open-label Two-arm Phase III Comparative Study Assessing the Role of Involved Mediastinal Radiotherapy after Rituximab Containing Chemotherapy Regimens to Patients With Newly Diagnosed Primary Mediastinal Large B-Cell Lymphoma


  • Study type

  • Study phase

  • Study IDs

  • Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • During the early phases (phases 1 and 2), researchers assess safety, side effects, optimal dosages and risks/benefits. In the later phase (phase 3), researchers study whether the treatment works better than the current standard therapy. They also compare the safety of the new treatment with that of current treatments. Phase 3 trials include large numbers of people to make sure that the result is valid. There are also less common very early (phase 0) and later (phase 4) phases. Phase 0 trials are small trials that help researchers decide if a new agent should be tested in a phase 1 trial. Phase 4 trials look at long-term safety and effectiveness, after a new treatment has been approved and is on the market.

  • Site IRB
    • Rochester, Minnesota: 13-003692
    NCT ID: NCT01599559
    Sponsor Protocol Number: IELSG 37

About this study

Primary mediastinal large B cell lymphoma is treated with a combination of chemotherapy and the monoclonal antibody rituximab (chemoimmunotherapy).

Following chemoimmunotherapy patients receive radiation therapy if they have residues which may be active tumour. However at the end of chemoimmunotherapy the majority of patients show tissue scarring that is not necessarily active tumor. In recent years, PET/CT has proved to be a good tool to accurately identify active tumor from scar tissue in patients treated for mediastinal lymphoma.The purpose of this trial is to test whether radiation therapy is really necessary in patients where PET/CT has shown that the tumor is no longer active. Therefore we will compare radiation treatment with careful observation.

Patients that at the end of conventional treatment of chemoimmunotherapy have a negative PET/CT (i.e., without residues suspected to contain active tumor), will randomly assigned to two different treatment groups: one treatment group will receive the radiation treatment, and the other treatment group will receive careful observation.

The trial is planned according to a non-inferiority design aimed at demonstrating that progression free survival after the experimental treatment (observation) is not worse than after the standard comparator (mediastinal irradiation.Participation in this study could spare patients with complete remission at the end of chemo immunotherapy (PET/CT negative) radiation therapy that may be unnecessary.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria

Inclusion Criteria:

  • Previously untreated primary mediastinal diffuse large B-cell lymphoma, CD20 positive.
  • Patients must have histological confirmation of the diagnosis (it is recommended that the immunohistochemical panel includes: CD45, CD20, CD30, CD15, CD10, BCL6, BCL2, MUM-1), and in addition have a dominant mass within the anterior mediastinum.
  • No evidence of extranodal disease outside the chest including spleen and bone marrow.
  • Age at least 18 years.
  • Fit to receive chemotherapy and radiotherapy with curative intent.
  • Patients will be eligible if the treatment phase consisting in a Rituximab combined with any anthracycline-containing chemotherapy regimen without consolidation with autologous stem cell support (e.g., 6 cycles of CHOP14-21, DA-EPOCH, Mega-CHOP or 12 weeks of VACOP-B or MACOP-B).
  • At least 6 courses of Rituximab should be administered
  • Able and willing to give informed consent, and to undergo staging including PET scanning
  • Willingness to comply with an appropriate contraceptive method in women of childbearing potential or men.
  • Histological diagnostic material available for review.

Exclusion Criteria:

  • History of malignancy other than squamous cell carcinoma, basal cell carcinoma of the skin or carcinoma in situ of the cervix within the last 5 years.
  • Evidence of clinically significant cardiac disease at diagnosis, as defined by history of symptomatic ventricular arrhythmias, congestive heart failure or myocardial infarction within 12 months before study entry. Cardiac impairment due to local extension of lymphoma will not be an exclusion criterion in the absence of other cardiac disease.
  • Known HIV-positive serology.
  • Pregnant or lactating women.
  • Any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule.

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Grzegorz Nowakowski, M.D.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office



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