Nivolumab and BO-112 Before Surgery for the Treatment of Resectable Soft Tissue Sarcoma

Inclusion Criteria: * Written informed consent, and assent where appropriate, must be obtained from the subject prior to performing any protocol-related procedures, including screening evaluations * Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0-1 * Biopsy proven soft tissue sarcoma of the extremity, trunk or retroperitoneum including undifferentiated pleomorphic sarcoma, myxofibrosarcoma, leiomyosarcoma, dedifferentiated liposarcoma, synovial sarcoma, malignant peripheral nerve sheath tumor, or pleomorphic rhabdomyosarcoma. Undifferentiated pleomorphic sarcoma encompasses any of the following histologies: * Pleomorphic undifferentiated sarcoma * Unclassified spindle cell sarcoma * Spindle cell sarcoma not otherwise specified * Pleomorphic spindle cell sarcoma * Pleomorphic fibroblastic sarcoma * Undifferentiated high-grade pleomorphic sarcoma * Pleomorphic sarcoma with prominent inflammation * Pleomorphic sarcoma with giant cells * Malignant fibrous histiocytoma (including storiform-pleomorphic and inflammatory subtypes) * Fibrosarcoma * Tumor that is injectable * Hemoglobin \>= 9 g/dL * Absolute neutrophil count \>= 1,000/mm\^3 * Platelet count \>= 100,000/mm\^3 and transfusion independent * Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) =\< 2.5 x institutional upper limit of normal (ULN) * Serum creatinine \< 1.5 x ULN or creatinine clearance \> 60 mL/min for patients with creatinine levels above ULN (as deter…