This article provides a detailed review of the vascular manifestations affecting the skin in relationship to internal malignancies. Vascular abnormalities heralding internal malignancies can be divided into three main categories, consisting of disorders related to vascular dilatation (flushing, palmar erythema, and telangiaectasia), and disoders related to vascular occlusion or hypercoagulability states (purpura, cutaneous ischemia, and thrombophlebitis). Entities are discussed according to etiology. The treatment of these entities is mostly related to treating the underlying malignancy. The goal of this article is to enlighten the practicing dermatologist about the association of these vascular manifestations with internal malignancy, thus leading to prompt initiation of the proper workup and management.