9 May 2019 PSA is not a tumour marker, though it is an indicator of prostate health. Many diseases of the prostate alter PSA , so a high value is not synonymous with prostate cancer. It only draws attention to the possibility. Examples of prostate problems that alter PSA are: Infection Inflammation Trauma Cancer. Until the 1980s, prostate cancer was only usually diagnosed at a late stage. It was almost always symptoms caused by metastases (mainly in the bone) that led to diagnosis. However, after the introduction of an effective blood test , the possibility of measuring the prostate-specific antigen (PSA) began a new age of early diagnosis. In most cases, it was possible to diagnose the disease while it was still at a localised stage (confined to the prostate) and could therefore undergo curative treatment. The pillars of early diagnosis of prostate cancer are: Annual PSA measurement Digital rectal examination. This article was written with the support of physicians and other clinical professionals from the Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.