Coexistence of essential thrombocythemia and multiple myeloma.

We describe a patient with essential thrombocythemia (ET) who developed multiple myeloma (MM) 5 years after the initial diagnosis. A review of the literature revealed no additional reports of the association of these two diseases. Development of MM was not related to treatment of essential thrombocythemia. This association suggests an alteration at the pluripotential stem cell level.