For example, in a study which included 12 intra-mucosal carcinomas (pT1a) and 9 widely invasive carcinomas (pT > 1, intra-mucosal SRC presented with an indolent phenotype and low proliferative index characterised by absent immunoexpression of Ki-67 and p53 while advanced carcinomas displayed an aggressive phenotype with pleomorphic cells that were immunoreactive for Ki-67 and p53 [18]. Here, SRC is linked to carcinoma.