Bone scan of advanced polycythemia vera with malignant transformation

A 69-year-old man with polycythemia vera and myelofibrosis was seen with a 2-week history of increasing arm pain. A bone scan showed diffuse prominence of the long bones, especially in the metaphyseal and epiphyseal regions of the lower extremities. There was relative prominence of the proximal right humerus that suggested the presence of a malignant process in addition to marrow space expansion secondary to myelofibrosis. An MRI of the right upper extremity showed a permeated lesion in the proximal right humerus extending into the adjacent soft tissue with a large soft tissue component. At surgery, a biopsy was followed by placement of a humeral rod. The morphologic features of the tumor together with CD34 positivity were consistent with a granulocytic sarcoma. This is the first reported case of bone scintigraphic findings in advanced p. vera with myelofibrosis and malignant transformation. The case illustrates the scintigraphic appearance of extensive expansion of the marrow and suggests the importance of vigilance for relatively subtle changes of complicating malignancies.