Response to anti-PD1 immunotherapy in patients with metastatic cutaneous sarcoma: case reports and literature review.

Dermal sarcomas represent a group or rare malignancies of mesenchymal origin. Although surgical excision with wide margins can be curative, in the advanced/metastatic setting, treatment options are limited and the benefit from anthracycline-based chemotherapy or targeted agents is usually short-lived. Tumor mutational burden and PD-L1 expression scores can be used as predictive biomarker for response to immunotherapy in some metastatic cancers. The role of immune-checkpoint blockade for sarcoma patients remains investigational. Here we present three cases of dermal sarcomas with high TMB and PD-L1 expression and responses to anti-PD1 agents in two of them.