Measurement of PD-1, PD-L1, and PD-L2 gene expression was performed as described above using RNA extracted from 20 tissue sections, two per individual STS patient: 10 from treatment interface areas and 10 from untreated areas of soft tissue sarcomas that had undergone histotripsy treatment (Figure 3). Here, PDCD1LG2 is linked to soft tissue sarcoma.