The diagnostic and prognostic potential of this soluble molecule has been studied outside the cancer spectrum in the context of infection [12] and Parkinson’s disease [13], in different tumors outside the immunotherapy spectrum [14, 15], but within the frame of ICI based therapy it has been scarcely exploited, with one study in head and neck cancer showing how high pretreatment serum levels of sLAG-3 predicted worsened PFS and OS [16]. The gene discussed is LAG3; the disease is cancer.