Serum levels of neutrophil elastase within the TME have been shown to play a potential role as a diagnostic biomarker in CRC.(81) While serum matrix metalloproteinase‐9 (MMP‐9) was not considered to be an appropriate screening parameter for CRC,(82) tissue inhibitor of metalloproteinase‐1 (TIMP‐1) seems to have a potential diagnostic value.(83) Targeting related factors that are expressed by TAMs or neighboring cells within the TME and circulatory markers may further contribute to the overall diagnostic capacity. Here, MMP9 is linked to colorectal carcinoma.