NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,198 terms related to cancer and medicine.
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- polycythemia vera
- listen (PAH-lee-sy-THEE-mee-uh VAYR-uh)
- A disease in which there are too many red blood cells in the bone marrow and blood, causing the blood to thicken. The number of white blood cells and platelets may also increase. The extra blood cells may collect in the spleen and cause it to become enlarged. They may also cause bleeding problems and make clots form in blood vessels.