ALK and diffuse large B-cell lymphoma: While ectopic expression of CLTC-ALK in fibroblasts induced less STAT3 phosphorylation than other ALK-fusion proteins [15], a recent immunohistological study detected ubiquitous STAT3 hyperphosphorylation in two CLTC-ALK positive DLBCL cases compared to ALK negative DLBCL [23].