PSA value of 100μg/L puncture for benign is less likely, but there is a certain possibility. 1. PSA is prostate specific antigen, a single chain protein secreted by prostate, commonly used as a tumor marker for prostate cancer. the normal reference value of PSA is less than 4 μg/L. When the PSA value is elevated and the ratio of free PSA to total PSA is less than 0.25, it suggests the presence of prostate cancer. 2. In addition to prostate cancer, PSA can also be mildly elevated in benign diseases such as prostatitis and prostate hyperplasia, but often less than 10 μg/L. Meanwhile, PSA can also be mildly elevated after prostate massage, anal diagnosis, cystoscopy, etc., which often needs to be rechecked after a few days. If the PSA is 100μg/L, it suggests that there is a possibility of prostate cancer, and it is recommended to go to the regular hospital in time to improve the examination, clear diagnosis and timely treatment.