Using fibre diffraction, cancers can be diagnosed as soon as they start to grow, so they can be diagnosed very early. For most men, therefore, prostate cancers can be diagnosed as low grade in their twenties. At this stage, these cancers can be removed by chemotherapy and radiation – no radical prostatectomies are needed. After treatment, a further diffraction test will verify that the cancer has been totally removed. No further worries and all that is needed is a 3mm skin biopsy taken from stomach or buttocks with a Keyes Punch. To date, over 400 tests have been carried out, Sensitivity was 100% as there were no false negatives. All invasions were identified and characterised correctly. However there were 3 false positives so the specificity was 99.2%. Later these 3 were shown to be true, just earlier than any other test could identify.