SMAD4 and neoplasm: Most of the studies conducted to investigate whether these mutations play a role in tumor progression provide evidence that SMAD4 deletion is a negative prognostic factor [8–13], although recently Dal Molin et al. [14] failed to demonstrate that somatic KRAS, TP53, SMAD4 and CDKN2A mutations impact on PDAC survival in the very long-term.