A review of myeloproliferative disease with presentation in the head and neck region.

The diagnosis of an essential thrombocytosis is demonstrated in this presentation of a well-looking 53 year old man who had a five-year history of increasing facial asymmetry as evidenced by deviation of his mandible to the right and malocclusion. The enlarged mandibular condyle was the first manifestation of his underlying myeloproliferative disorder. His management will be discussed. Neoplastic diseases of the multipotent haematopoietic stem cells result in four major diseases: chronic myelogenous leukaemia (CML); polycythaemia vera (PV); agnogenic myeloid metaplasia with myelofibrosis (AMM/MF); essential thrombocytosis (ET). CML: demonstrates increased production of neutrophils and marked splenomegaly. It is divided into a chronic phrase typified by hyperplasia of mature bone marrow elements and a blastic or acute phase which evolves into a proliferation of immature marrow elements and can develop into acute myelogenous leukaemia. PV: associated with increased production of all myeloid cells but dominated by increased red blood cells with splenomegaly. AMM/MF: allows the neoplastic stem cells to proliferate and lodge in multiple sites outside the bone marrow. Splenomegaly and fibrosis of marrow spaces also occurs. ET: resulting in a markedly elevated platelet count in the absence of a recognizable stimulus. Treatment revolves around measures to maintain hydration, to relieve arthralgias, to prevent thrombotic episodes, and to prevent infections.