Durable remission of both multicentric Castleman's disease and Kaposi's sarcoma with valganciclovir, rituximab and liposomal doxorubicin in an HHV‐8‐positive, HIV‐negative patient

WHAT IS KNOWN AND OBJECTIVE: Human herpesvirus-8 (HHV-8)-positive, HIV-negative multicentric Castleman's disease is a rare lymphoproliferative disorder with no standardized treatment. Concurrent Kaposi's sarcoma, another HHV-8-related disease, is uncommon in HIV-negative patients. The role of antiviral therapy and rituximab in HIV-negative patients is not well established. CASE DESCRIPTION: We report a case of a 5-year, durable remission of HHV-8-positive, HIV-negative comorbid multicentric Castleman's disease and Kaposi's sarcoma treated with long-term valganciclovir, following initial rituximab and liposomal doxorubicin. WHAT IS NEW AND CONCLUSION: Currently, there is no defined role for antiviral therapy in the treatment of HIV-negative HHV-8-positive multicentric Castleman's disease and Kaposi's sarcoma. Ganciclovir followed by indefinite, continuous valganciclovir is thought to have contributed significantly to the durable response in this case.