In total, we found that the Fat/Dachsous family was altered in 9/49 (18%) ALCL patients (6/33 ALK+ and 3/16 ALK-), including a deep deletion of FAT1 and mutations of FAT3 and the FAT ligand DCHS1 (Fig. 1f). Here, FAT3 is linked to anaplastic large cell lymphoma.