Remarkably, while suppressing neurofibromas, genetic deficiency of NF-κB1 promotes immortalization of Tax-expressing macrophages and causes massive infiltration of neoplastic macrophages into the spleen, lymph nodes and adrenal glands, resulting in splenomegaly, lymphadenopathy and adrenomegaly in mice. This evidence concerns the gene NFKB1 and Lymphadenopathy.