Consequently, patients harboring HLA-DQB1*03:03, HLA-C*01:02, or HLA-B*52:01 exhibit a heightened susceptibility to irAEs, an effect that is especially pronounced in the presence of type B thymoma but remains evident even in non-thymoma cohorts, underscoring the independent and synergistic contributions of both thymoma biology and HLA genotype. Here, HLA-C is linked to thymoma.