IL6 and Pleural effusion: Current studies suggest induction therapy increases cytokine (IL-1, IL-6, TNF-α) and adhesion molecules (CD116, CDw65, VLA-4, CD11a/CD54) secretion, promoting APL cell migration to the lungs and causing clinical symptoms such as fever, weight gain, musculoskeletal pain, respiratory distress, pulmonary interstitial infiltration, pleural effusion, pericardial effusion, skin edema, hypotension, acute renal failure, and death.