B2M and colorectal carcinoma: In uveal melanoma, which has many similarities with dMMR CRC (preferential haematogenous spread to the liver and similar B2M mutation pattern), loss of HLA‐class I/B2M expression is also associated with significantly improved survival.24, 25 The role of NK activity and HLA class I loss in the prevention of distant metastases has been extensively investigated in uveal melanoma and fibrosarcoma, in both in in‐vitro studies and mouse models.26, 27, 28, 29