Waldenstrom's macroglobulinaemia is a rare type of cancer which has been described as a hybrid of lymphoma and myeloma. B-lymphoctyes are transformed into cancer cells in the last stage of their maturation process. The disease is fatal, though treatment may extend survival many years after diagnosis.
It is estimated that as many as 50 people per million have the disease in the USA. Other estimates are lower and collectively place the number affected in the USA at any one time as between 4,000 and 13,400.