Patent ID: 8030085

Claim:
A method for discriminating between prostate carcinoma and benign prostatic hyperplasia, comprising the steps of: (1) purifying prostate specific antigen (PSA) PSA from a sample derived from a subject; (2) preparing a PSA derivative from the PSA purified in Step (1); (3) labeling the PSA derivative obtained in Step (2); (4) analyzing the labeled PSA derivative obtained in Step (3) by a mass spectrometry method; and (5) determining a ratio of a signal intensity of fucose-unbound glycan to a signal intensity of fucose-bound glycan in the labeled PSA derivative, wherein the subject is identified as having prostate carcinoma when the ratio is greater than 1.0, and identified as having benign prostatic hyperplasia when the ratio is 1.0 or less.