The first therapeutic interventions taking advantage of CD16 function on NK cells were based on the administration of tumor-targeting chimeric monoclonal antibodies (mAbs), such as rituximab, a mAb recognizing CD20 that still represents a first-line treatment in B-chronic lymphocytic leukemia (B-CLL) [181] (Figure 2). The gene discussed is FCGR3A; the disease is neoplasm.