Our mini-bulk proteomic survey of 500 blood CD10− low density neutrophils (LDN), CD10+ LDN, CD10+ normal density neutrophils (NDN) and CD45+CD66b+CD49d− tumour associated neutrophils (TANs) using ultra-sensitive mass spectrometry revealed proteomic similarities between CD10+ blood neutrophils and TANs, however it also highlighted clear differences between the CD10− LDN and TAN populations. The gene discussed is CEACAM8; the disease is neoplasm.