Manipulating the Immune System With Checkpoint Inhibitors for Patients With Metastatic Sarcoma.

Sarcomas are a rare group of malignant tumors of mesenchymal origin that comprise 1% of all adult cancers. Despite initial surgery, distant metastatic disease will develop in approximately 25% of patients, and standard chemotherapy has limited durable efficacy. There is a dire need for more effective and less toxic therapies for the treatment of metastatic sarcoma. The immune system plays a major role in cancer control and progression. There have been tremendous breakthroughs in other malignancies by manipulating the immune system with checkpoint inhibitors. These agents, either alone or in combination with other approaches such as radiation, chemotherapy, targeted agents, or immunotherapeutics, have generally led to improved efficacy in selected malignancies thus far. Although promising, these drugs can cause specific immune-related adverse events that require prompt recognition and treatment. In addition, characterizing response and progression radiographically has become somewhat more challenging. Identifying predictive biomarkers of benefit will be essential. There remains optimism and hope that the strides made in other cancers will be emulated in sarcoma.