Although the region containing CSMD1 is frequently deleted in head and neck squamous cell carcinomas and prostatic adenocarcinomas [3,11-15], point mutations in the gene are relatively rare in primary squamous cancers [16] and in squamous cell carcinoma cell lines (Schmidt, Richter and Scholnick, unpublished). Here, CSMD1 is linked to head and neck squamous cell carcinoma.