As myelofibrosis (MF) progresses, complications may arise.
Increased blood flow from an enlarged spleen can lead to high blood pressure within the portal vein, which carries blood from the spleen to the liver. This can force excess blood into smaller veins in the stomach and esophagus, potentially causing the veins to rupture and bleed.
Formation of blood cells outside the bone marrow, called “extramedullary hematopoiesis,” may create clumps (tumors) of developing blood cells in other areas of the body. These tumors may cause such problems as bleeding in the gastrointestinal system, coughing or spitting up blood, compression of the spinal cord or seizures.
Hardening and Inflammation of Bone Tissue
Myelofibrosis can cause hardening of the bone marrow and inflammation of the connective tissue that surrounds the bones, resulting in severe bone and joint pain and tenderness.
Because MF increases the body’s production of uric acid, a byproduct of the breakdown of purines—a substance found naturally in the body—needlelike deposits of uric acid can form in the joints, causing joint pain and inflammation (gout).
Acute Myeloid Leukemia (AML)
In about 15 to 20 percent of patients with myelofibrosis, MF will transform to AML, a type of blood and bone marrow cancer that progresses rapidly.