IL21 and leukemia: For example, increased serum and peritoneal fluid levels of IL-16, IL-21, chemokine C-C motif ligand 8 or monocyte chemotactic protein-2 (CCL8/MCP-2), chemokine C-X-C motif ligand 13 or monocyte chemotactic protein −4 (CCL13/MCP-4), C-X-C motif chemokine 5 or epithelial neutrophil-activating-peptide (CXCL5/ENA-78), leukemia inhibitory factors on the third postoperative day were found to be associated with the occurrence of anastomotic leaks after colorectal surgery.