IWG-MRT Myelofibrosis Spleen Response

**Semantic type:** Finding

**Definition:** A baseline splenomegaly that is palpable at 5-10 cm below the left costal margin becomes not palpable or A baseline splenomegaly that is palpable at greater than 10 cm below the left costal margin decreases by greater than or equal to 50 percent. A baseline splenomegaly that is palpable at less than 5 cm below the left costal margin is not eligible for spleen response. A spleen response requires confirmation by MRI or computed tomography showing greater than or equal to 35 percent spleen volume reduction. (adapted from Revised Response Criteria for Myelofibrosis: International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) and European LeukemiaNet (ELN) consensus report. BLOOD 22 AUGUST 2013 x VOLUME 122 NUMBER 8)