Apart of the hematopoietic system, elevated expression of BTK was recently reported in several solid tumor entities, like breast [8], ovarian [9,10], prostate [11,12], colon [13,14], gastric carcinoma [15], glioma [16,17,18] as well as non-small-cell lung carcinoma (NSCLC) [19]. Here, BTK is linked to non-small cell lung carcinoma.