Disease of the bone marrow in which excess cells are produced.
A group of related and highly similar diseases that involve abnormally high production of certain kinds of blood cells because of malfunction of the bone marrow. The myeloproliferative diseases differ from one another in the primary type of blood cell affected. Normal bone marrow contains cells, known as hematopoietic cells or stem cells, that have the ability to reproduce themselves into what is known as a clone. Each clone can produce different cell lines that develop into red blood cells, one of several kinds of white blood cells, and platelets (cells that have key roles in blood clotting). In normal bone marrow, a number of clones are active in producing normal blood cells in normal proportions. In the myeloproliferative disorders, an abnormal clone takes over from the others, producing blood cells of one type that are essentially normal yet far too abundant, while the number of other blood cell types may be too low.
Any of several hematologic malignancies marked by the excessive multiplication of one or more types of blood cells. These disorders include polycythemia rubra vera, essential thrombocytosis, chronic myeloid leukemia, and idiopathic myelofibrosis.
A hyperproliferative disorder of the bone marrow manifests when there is an excessive and rapid production of cells.
Medical conditions distinguished by the abnormal growth of one or more groups of blood cells within the bone marrow.