KRAS and neoplasm: These changes impede neoantigen processing and presentation, hence inhibiting T cell recognition and tumor killing.316,490 The tumors may be able to avoid recognition by adoptively transferred T lymphocytes if there are mutations in key antigen presentation genes like β2M or a lack of HLA allele heterozygosity.316,380 For example, all seven lung metastases from a colorectal cancer patient regressed after receiving an infusion of TILs containing four unique T cell clonotypes that target KRAS-G12D.