Nodular spindle cell proliferation in the wall of a varicose vein mimicking Kaposi's sarcoma

Exuberant reparative reactions resembling sarcoma have been reported in the genitourinary tract, thyroid, breast, lymph node, oral cavity and skin, but not in a varicose vein. Presented herein is the case of a 55-year-old man who showed an incidental nodular lesion in the wall of a varicose vein on the left leg. The nodule consisted of fascicles of spindled cells with ovoid or elongated nuclei and delicate chromatin that showed diffuse reactivity for CD31, alpha-smooth muscle actin and D2-40. This histopathological appearance, when coupled with extravasated erythrocytes and interstitial hemosiderin deposits, resembled Kaposi's sarcoma or spindle cell angiosarcoma. Key features helpful for recognizing that the proliferation we describe is a form of tissue repair include an association with obvious hemorrhage; lack of well-formed curved fascicles of spindled cells; lack of intracytoplasmic hyaline globules; lack of intracellular vacuolization; cytological blandness; low mitotic count; absence of inmmunoreactivity for human herpesvirus-8 (HHV-8) latent nuclear antigen-1; and absence of HHV-8 in polymerase chain reaction (PCR) analysis.