Castleman disease (CD), an atypical lymphoproliferative disorder of unknown etiology, is rare. Unicentric CD can be cured after resection of the involved lymph nodes. However, rarely, patients with the unicentric-plasma cell variant may require additional therapy after resection for persistent systemic symptoms. The clinical course of such patients has not been well characterized. We report the case with relapsed unicentric-plasma cell variant CD who was eventually treated with complete surgical resection. This patient had no response to combination chemotherapy with rituximab after incomplete resection and no response to radiation after relapse.