TBX1 and leukemia: Although CAFs have been reported to be present in most solid tumors, there is a significant degree of variability regarding their abundance among cancers, with pancreatic adenocarcinoma, breast carcinoma, lung adenocarcinoma and kidney renal clear cell carcinoma, being typically heavily infiltrated with CAFs, and leukemia, lymphoma and brain tumors being mostly devoid of CAFs.