CUTANEOUS VASCULAR PROLIFERATIONS - PART-III - MALIGNANT NEOPLASMS, OTHER CUTANEOUS NEOPLASMS WITH SIGNIFICANT VASCULAR COMPONENT, AND DISORDERS ERRONEOUSLY CONSIDERED AS VASCULAR NEOPLASMS

In this third and last part of our review of cutaneous vascular prolif erations we include malignant vascular neoplasms and a group of hetero geneous cutaneous neoplasms characterized by a significant vascular co mponent. We also review some disorders that, in our opinion, have been erroneously considered as vascular neoplasms. We review the epidemiol ogic, histogenetic, clinical, and histopathologic aspects of Kaposi's sarcoma in its four distinctive variants (classic, African-endemic, im munosuppressive drug-associated, and AIDS-associated Kaposi's sarcoma) . There is still controversy about whether Kaposi's sarcoma represents a reactive vascular proliferation or a true neoplastic proliferation. In any event, most authors believe that Kaposi's sarcoma does not pro duce metastatic disease, but rather develops in multifocal fashion. Ho wever, Kaposi's sarcoma may cause death, especially in immunosuppresse d patients. Epithelioid hemangioendothelioma, Dabska's tumor, and reti form hemangioendothelioma are examples of low-grade angiosarcoma. In c ontrast, cutaneous angiosarcomas, including the clinical variants of a ngiosarcoma of face and scalp in elderly patients, angiosarcoma associ ated with lymphedema, and radiation-induced angiosarcoma are highly ag gressive neoplasms with poor prognosis and most patients die within a short period after presentation. A group of benign and relatively freq uent cutaneous neoplasms, including multinucleate cell angiohistiocyto ma, angiofibroma, angioleiomyoma, angiolipoma, cutaneous angiolipoleio myoma, and cutaneous angiomyxoma are here covered because of their sig nificant vascular component. Finally, we review briefly a series of cu taneous disorders that have been erroneously considered as vascular ne oplasms. Kimura's disease is an inflammatory reactive condition of unk nown origin, ''benign'' angioendotheliomatosis is a reactive intravasc ular proliferation of endothelial cells that occurs in the skin as a r esponse to a variety of stimuli, ''malignant'' angioendotheliomatosis is an intravascular lymphoma, and acral pseudolymphomatous angiokerato ma of children (APACHE) is better interpreted as a pseudolymphoma.