Since tumor cell plasticity was first shown to be crucial in tumor promotion and immune surveillance evasion, it has become an issue of intense investigation. Several mechanisms are associated with the acquisition of tumor cell plasticity and immune evasion, including loss of epithelial phenotype through epithelial-to-mesenchymal transition (EMT). We discuss recent evidence revealing that tumor cell plasticity may lead to the emergence of immunoresistant variants and how the tumor microenvironment evolves to shape this plasticity. We argue that targeting carcinoma cell plasticity represents a novel strategy to better control the emergence of resistant variants and to ensure more effective cancer therapies. In this context, the design of innovative integrative immunotherapy approaches is warranted.