The 862 m/z (RT 50.2 min) peak annotated as a fragment of CXCL-7 was specifically expressed in pancreatic cancer patients, with an AUC of 0.839 (P = 4.54 × 10−5 by Mann-Whitney U test) (Figure 2(a)). The gene discussed is PPBP; the disease is familial pancreatic carcinoma.