A method for diagnosing a patient's risk of developing pancreatic cancer, or the presence of pancreatic cancer in a patient, comprising the steps of: a) analyzing a blood sample from said patient to obtain quantifying data for one or more than one metabolite marker; b) comparing the quantifying data for said one or more than one metabolite marker to corresponding data obtained for one or more than one reference sample to identify an increase or decrease in the level of said one or more than one metabolite marker in said blood sample; and c) using said increase or decrease in the level of said one or more than one metabolite marker in said blood sample for diagnosing said risk of developing pancreatic cancer, or the presence of pancreatic cancer in said patient, wherein the one or more metabolite marker comprises: (i) a diacylphosphatidylcholine, plasmanylphosphocholine or plasmenylphosphocholine of Formula: including salts thereof, wherein R 1 is a 16:0, 16:1, 18:0, 18:1, 18:2, 18:3, 20:3, 20:4, 20:5, 22:5 or 22:6 fatty acid or alcohol moiety bonded to the glycerol backbone, the bond being an acyl linkage when the metabolite marker comprises a diacylphosphatidylcholine, an ether linkage when the metabolite marker comprises a plasmanylphosphocholine, or a vinyl-ether linkage when the metabolite marker comprises a plasmenylphosphocholine; and R 2 is a 16:0, 16;1, 18:0, 18:1, 18:2, 18:3, 20:3,20:4, 20:5, 22:5, or 22:6 fatty acid moiety bonded to the glycerol backbone through an acyl linkage; (ii) a 2-lysophosphatidylcholine of Formula or 1-lysophosphatidylcholine of Formula: including salts thereof, wherein R 1 is a 14;1, 16:0, 16:1, 16:2, 18:0, 18:1, 18:2, 18:3, 20:1, 20:2, 20:3, 20:4, 20;5, 20:6, 22:3, 22;4, 22:5, 22:6, 24:4, 24:6, 30: t, 32:0, 32:1, 32:2 or 32:6 fatty acid moiety bonded to the glycerol backbone through an acyl linkage; or (iii) a sphingomyelin as defined in Formula: including salts thereof, wherein the dashed line represents an optional double bond; R 1 is a C 13 alkyle group; and R 2 is a C 11 to C 25 alkyle or alkenyl group, said alkenyl group having from 1 to 3 double bonds. a) analyzing a blood sample from said patient to obtain quantifying data for one or more than one metabolite marker; b) comparing the quantifying data for said one or more than one metabolite marker to corresponding data obtained for one or more than one reference sample to identify an increase or decrease in the level of said one or more than one metabolite marker in said blood sample; and c) using said increase or decrease in the level of said one or more than one metabolite marker in said blood sample for diagnosing said risk of developing pancreatic cancer, or the presence of pancreatic cancer in said patient, (i) a diacylphosphatidylcholine, plasmanylphosphocholine or plasmenylphosphocholine of Formula: including salts thereof, wherein R 1 is a 16:0, 16:1, 18:0, 18:1, 18:2, 18:3, 20:3, 20:4, 20:5, 22:5 or 22:6 fatty acid or alcohol moiety bonded to the glycerol backbone, the bond being an acyl linkage when the metabolite marker comprises a diacylphosphatidylcholine, an ether linkage when the metabolite marker comprises a plasmanylphosphocholine, or a vinyl-ether linkage when the metabolite marker comprises a plasmenylphosphocholine; and R 2 is a 16:0, 16;1, 18:0, 18:1, 18:2, 18:3, 20:3,20:4, 20:5, 22:5, or 22:6 fatty acid moiety bonded to the glycerol backbone through an acyl linkage; R 1 is a 16:0, 16:1, 18:0, 18:1, 18:2, 18:3, 20:3, 20:4, 20:5, 22:5 or 22:6 fatty acid or alcohol moiety bonded to the glycerol backbone, the bond being an acyl linkage when the metabolite marker comprises a diacylphosphatidylcholine, an ether linkage when the metabolite marker comprises a plasmanylphosphocholine, or a vinyl-ether linkage when the metabolite marker comprises a plasmenylphosphocholine; and R 2 is a 16:0, 16;1, 18:0, 18:1, 18:2, 18:3, 20:3,20:4, 20:5, 22:5, or 22:6 fatty acid moiety bonded to the glycerol backbone through an acyl linkage; (ii) a 2-lysophosphatidylcholine of Formula or 1-lysophosphatidylcholine of Formula: including salts thereof, wherein R 1 is a 14;1, 16:0, 16:1, 16:2, 18:0, 18:1, 18:2, 18:3, 20:1, 20:2, 20:3, 20:4, 20;5, 20:6, 22:3, 22;4, 22:5, 22:6, 24:4, 24:6, 30: t, 32:0, 32:1, 32:2 or 32:6 fatty acid moiety bonded to the glycerol backbone through an acyl linkage; or R 1 is a 14;1, 16:0, 16:1, 16:2, 18:0, 18:1, 18:2, 18:3, 20:1, 20:2, 20:3, 20:4, 20;5, 20:6, 22:3, 22;4, 22:5, 22:6, 24:4, 24:6, 30: t, 32:0, 32:1, 32:2 or 32:6 fatty acid moiety bonded to the glycerol backbone through an acyl linkage; or (iii) a sphingomyelin as defined in Formula: including salts thereof, wherein the dashed line represents an optional double bond; R 1 is a C 13 alkyle group; and R 2 is a C 11 to C 25 alkyle or alkenyl group, said alkenyl group having from 1 to 3 double bonds. R 1 is a C 13 alkyle group; and R 2 is a C 11 to C 25 alkyle or alkenyl group, said alkenyl group having from 1 to 3 double bonds.