The rearrangements of the ALK gene have been implicated in the pathogenicity of a number of neoplasms that include anaplastic large cell lymphoma (ALCL), a subset of pulmonary adenocarcinoma, inflammatory myofibroblastic tumor (IMT), and epithelioid fibrous histiocytoma (EFH); the rearrangements result in fusion proteins that constitutively activate the ALK tyrosine kinase domain [8–10]. The gene discussed is ALK; the disease is anaplastic large cell lymphoma.