A method of classifying the type of endometrial cancer as a fibroblast growth factor receptor 2 (FGFR2) activation induced endometrial cancer in a subject, the method comprising screening for a receptor mutation in a FGFR2 in a biological sample containing endometrial cancer cells in vitro, wherein the FGFR2 mutation is associated with FGFR2 receptor activation which increases the level of activity of a FGFR2 signal transduction pathway compared to a control, and classifying the type of endometrial cancer as a FGFR2 activation induced endometrial cancer upon detecting a FGFR2 activation mutation in the endometrial cancer cells, wherein the mutation is an amino acid substitution in FGFR2 selected from the group consisting of: (a) a S to W mutation at position 252 of SEQ ID NOS:2 or 3; (b) a K to R mutation at position 310 of SEQ ID NOS:2 or 3; (c) an A to T mutation at position 315 of SEQ ID NO:3; (d) a S to C mutation at position 373 of SEQ ID NO:2 or position 372 of SEQ ID NO:3; (e) a Y to C mutation at position 376 of SEQ ID NO:2 or position 375 of SEQ ID NO:3; (f) a C to R mutation at position 383 of SEQ ID NO:2 or position 382 of SEQ ID NO:3; (g) a M to R mutation at position 392 of SEQ ID NO: 2 or position 391 of SEQ ID NO:3; (h) an I to V mutation at position 548 of SEQ ID NO:2 or position 547 of SEQ ID NO:3; (i) N to K mutation at position 550 of SEQ ID NO:2 or position 549 of SEQ ID NO:3; or (j) a K to E mutation at position 660 of SEQ ID NO:2 or position 659 of SEQ ID NO:3, or the mutation is a nucleotide substitution selected from the group consisting of: (i) an A to G mutation at position 929 of SEQ ID NO:1; (ii) a T to G mutation at position 1650 of SEQ ID NO:1; (iii) a C to G mutation at position 755 of SEQ ID NO:1; (iv) a T to A mutation at position 1650 of SEQ ID NO:1; (v) an A to G mutation at position 1127 of SEQ ID NO: 1; (vi) a C to G mutation at position 1118 of SEQ ID NO: 1; (vii) a T to C mutation at position 1147 of SEQ ID NO:1; (viii) a T to G mutation at position 1175 of SEQ ID NO:1; (ix) an A to G mutation at position 1642 of SEQ ID NO:1; (x) an A to G mutation at position 1978 of SEQ ID NO:1. (a) a S to W mutation at position 252 of SEQ ID NOS:2 or 3; (b) a K to R mutation at position 310 of SEQ ID NOS:2 or 3; (c) an A to T mutation at position 315 of SEQ ID NO:3; (d) a S to C mutation at position 373 of SEQ ID NO:2 or position 372 of SEQ ID NO:3; (e) a Y to C mutation at position 376 of SEQ ID NO:2 or position 375 of SEQ ID NO:3; (f) a C to R mutation at position 383 of SEQ ID NO:2 or position 382 of SEQ ID NO:3; (g) a M to R mutation at position 392 of SEQ ID NO: 2 or position 391 of SEQ ID NO:3; (h) an I to V mutation at position 548 of SEQ ID NO:2 or position 547 of SEQ ID NO:3; (i) N to K mutation at position 550 of SEQ ID NO:2 or position 549 of SEQ ID NO:3; or (j) a K to E mutation at position 660 of SEQ ID NO:2 or position 659 of SEQ ID NO:3, (i) an A to G mutation at position 929 of SEQ ID NO:1; (ii) a T to G mutation at position 1650 of SEQ ID NO:1; (iii) a C to G mutation at position 755 of SEQ ID NO:1; (iv) a T to A mutation at position 1650 of SEQ ID NO:1; (v) an A to G mutation at position 1127 of SEQ ID NO: 1; (vi) a C to G mutation at position 1118 of SEQ ID NO: 1; (vii) a T to C mutation at position 1147 of SEQ ID NO:1; (viii) a T to G mutation at position 1175 of SEQ ID NO:1; (ix) an A to G mutation at position 1642 of SEQ ID NO:1; (x) an A to G mutation at position 1978 of SEQ ID NO:1.