Classic Kaposi's sarcoma treated with topical rapamycin

Kaposi's sarcoma (KS) is an angioproliferative disorder caused by human herpesvirus 8 (HHV-8). Current research efforts have focused on the study of the relative role of KSHV-encoded genes in Kaposi's sarcomagenesis in order to identify novel mechanism-based therapies for patients suffering from this tumor. Although several viral genes have potential for KS pathogenesis, compelling data point to the KSHV-encoded G protein-coupled receptor (vGPCR) as a leading candidate viral gene for the initiation of KS. Interestingly, the oncogenic potential of vGPCR seems to correlate with its capacity to activate the mammalian target of rapamycin (mTOR) signaling pathway. Rapamycin, the prototypical inhibitor of the mTOR signaling pathway, has recently emerged as an effective treatment for KS when administered orally. In this case report, we present an immunocompetent patient with KS lesions treated with topical rapamycin achieving clinical and histologic healing after 16 weeks of treatment. The topical application of rapamycin could be a novel therapeutic option for the treatment of KS.