Targeting angiosarcomas of the soft tissues: A challenging effort in a heterogeneous and rare disease.

Angiosarcomas are rare malignant tumors with a heterogeneous clinical presentation and generally poor prognosis. It has been difficult to establish consistent molecular characteristics and driver events in angiosarcoma development. Oncogenic and angiogenesis-related pathways have been investigated pre-clinically and clinically with varying results. A few promising responses to checkpoint inhibitors have been described, but immunological features require further elucidation. With this review we present an overview of the critical biological pathways and processes affected in angiosarcoma, and their potential role in novel, non-cytotoxic, systemic treatments.