Interestingly, most of mGIST patients belonging to group of LTS (PFS > 36 months) showed lower plasma levels for each soluble biomarker (sPD-1, sPD-L1, sBTN3A1, and pan-sBTN3As), whereas STS patients (PFS ≤ 36 months) predominantly exhibited higher circulating levels of these molecules. The gene discussed is SPDL1; the disease is telomere syndrome.