Methods for diagnosing prostate cancer, and differentiate prostate cancer from other prostate complications, and use of said method, and diagnosing and monitoring lymph gland metastasis, post-operative examinations, and examinations during or after radiation, cytostatic, and androgen treatments are disclosed. The methods comprise injecting tracer-labelled PSA or hK2 specific antibodies, visualising PSA or hK2 producing tissue with the aid of a visualisation method, and diagnosing prostate cancer from the difference in visualisation.