A study of appendiceal adenocarcinomas found that neoplasms that were KRAS mutant and GNAS wild type were associated with better overall survival than neoplasms with mutations in both genes [19], and a study of PMP of appendiceal origin found a mutation in any one of TP53, SMAD4, ATM, CDKN2A, PIK3CA or PTEN was associated with worse overall survival [28]. This evidence concerns the gene GNAS and neoplasm.