Anaplastic Lymphoma Kinase (ALK) is a receptor tyrosine kinase aberrantlyexpressed in a variety of tumor types, most notably in Anaplastic Large CellLymphoma (ALCL) where a chromosomal translocation generates the oncogenic fusionprotein, Nucleophosmin-ALK (NPM-ALK). Here, NPM1 is linked to anaplastic large cell lymphoma.