B-cell compartment reconstitution takes place 3–4 months after the end of treatment, and prolonged (>800 days) low levels of IgA, IgM, and IgG were reported in 25%, 13%, and 9% of the pediatric population with NHL that was treated with rituximab, respectively [32,33]. The gene discussed is CD79A; the disease is non-Hodgkin lymphoma.