Myelofibrosis is a rare blood disorder characterized by the abnormal growth of bone marrow tissue, leading to the formation of scar tissue. This condition disrupts the production of blood cells, resulting in anemia, fatigue, and an enlarged spleen. It is classified as a type of myeloproliferative neoplasm, which is a group of disorders that cause the bone marrow to produce too many blood cells. The exact cause of myelofibrosis is often unknown, but it can be associated with mutations in genes such as JAK2, CALR, or MPL. Diagnosis typically involves blood tests, bone marrow biopsies, and imaging studies. Treatment options may include medications, blood transfusions, or, in severe cases, a stem cell transplant.