Abstract: A method of determining whether a subject has cancer or has a risk of getting cancer comprises: detecting the concentration of Hsp90a in a blood sample of the subject; and if the concentration reaches or exceeds a preset threshold value, determining that the subject has cancer or has a risk of getting cancer, where the threshold value is selected from a range from 50 ng/ml to 120 ng/ml; for example, the threshold value may be 50, 53, 56, 62, 63, 64, 67, 72, 82, 85 or 117 ng/ml, and a numerical value within the ±15% range of the threshold value is regarded having equivalent significance for determination.