Polycythemia vera (PCV), polycythemia rubra vera (PRV), or erythremia, occurs when excess red blood cells are produced as a result of an abnormality of the bone marrow. Often, excess white blood cells and platelets are also produced. PCV is classified as a myeloproliferative disease. Symptoms include headaches and vertigo, and signs on physical examination include an abnormally enlarged spleen and/or liver. In some cases, affected individuals may have associated conditions including high blood pressure or formation of blood clots. Transformation to acute leukemia is rare. Phlebotomy is the mainstay of treatment. A hallmark of polycythemia is an elevated hematocrit, with Hct > 55% seen in 83% of cases. A somatic (non-hereditary) mutation (V617F) in  the JAK2 gene, also present in other myeloproliferative disorders, is found in 95% of cases.Primary familial polycythemia, also known as primary familial and congenital polycythemia (PFCP), exists as a benign hereditary condition, in contrast with the myeloproliferative changes associated with acquired PCV. In many families, PFCP is due to an autosomal dominant mutation in the EPOR erythropoietin receptor gene. PFCP can cause an increase of up to 50% in the oxygen-carrying capacity of the blood; skier Eero Mäntyranta had PFCP, which is considered to have given him a large advantage in endurance events. Secondary polycythemia
Secondary polycythemia is caused by either natural or artificial increases in the production of erythropoietin, hence an increased production of erythrocytes. In secondary polycythemia,  6 to 8 million and occasionally 9 million erythrocytes may occur per cubic millimeter of blood.
Tumor was intertwined with quadriceps muscles, making identification and excision difficult. Tumor was successfully excised with only minor rehabilitation required. Familial leiomyoma
Associated with papillary variant of renal cell carcinoma and multiple cutaneous leiomyoma. Defect is in the fumarate hydratase gene in the long arm of chromosome 1. See also
Leiomyosarcoma
Elagolix/estradiol/norethindrone acetate

References
External links

Esophageal Leiomyoma at eMedicine