Vascular lesions are a complex group of neoplasms and malformations. Although benign vascular tumors are frequently encountered, their malignant counterparts are rare and comprise less than 1% of all soft tissue sarcomas. Their rarity is one of the reasons they pose a diagnostic challenge to pathologists. Other reasons include the overlapping morphologic features between malignant vascular neoplasms with divergent biologic potential and even between benign and malignant entities. Because of the significant clinical consequences, this review focuses on the lesions of intermediate malignancy (locally aggressive without metastatic potential and forms of low-grade malignant neoplasms) as compared with angiosarcoma.