Introduction:

In primary immunodeficiencies there is a failure in the anti-tumor defense. Common variable immunodeficiency (CVID) is one of the most common primary immunodeficiencies characterized by an alteration in the differentiation of B lymphocytes (BL). Epstein-Barr virus (EBV) is an ubiquitous virus that selectively infects the BL. In patients with immunodeficiency, uncontrolled proliferation of infected BL and the action of viral proteins promote the development of lymphomas.

Clinical cases:

At the University Hospital Sant Joan de Deu, Barcelona, 28 patients were diagnosed with CVID from 2000 to 2013. This paper describes four patients who developed non-Hodgkin's lymphoma (NHL). The lymphoma was associated with EBV in two of the cases. Patients were < 18 years old, diagnosed with lymphoma between 4 and 13 years old. Two patients were treated with rituximab as monotherapy and achieved complete remission. Two patients were treated with CHOP (cyclophosphamide, doxorubicin, vincristine and prednisolone) and radiotherapy or rituximab and achieved complete remission.

Conclusions:

Early detection of EBV infections and NHL in all patients diagnosed with CVID is recommended, regardless of age at diagnosis.