The present invention provides methods and kits for assessing whether a subject is afflicted with an FR±-expressing cancer, methods and kits for predicting the progression of ovarian cancer in a subject afflicted with an FR±-expressing cancer, methods and kits for assessing the level of risk that a subject will develop an FR±-expressing cancer, and methods of stratifying a subject with an FR±-expressing cancer into cancer therapy groups. The methods involve determining the level of folate receptor alpha (FR±) which is not bound to a cell in a sample derived from the subject and comparing this level with the level of FR± in a control sample.