An acute terminal phase of a Bence Jones kappa plasma cell myeloma developed 22 months after chemotherapy is presented. The patient's symptoms were fever, cytopenias, adenomegalies and hepatomegaly. A lymph node biopsy showed an immunoblastic polymorphic kappa B cell lymphoma, expressing CD30 antigen. After new polychemotherapy the patient died because of bleeding and infection. Autopsy revealed a decrease in the tumour with defective immunophenotype. The few reported cases have been reviewed with emphasis on clinical aspects, prognosis and morphology, The significance of CD30 positivity (activation marker) in a high-grade lymphoma is discussed.