Prostate cancer became a major public health problem on the threshold of the third millennium. The trilogy rectal touch, PSA-iso forms and biopsy is the pillar of the diagnostic approach and a pragmatic reflection. This is a retrospective study including the analysis of the medical records of 1053 patients admitted between 2000 and 2015. The inclusion criterion is a rate of PSA-T between 4 and 10 ng / ml which corresponds to 783 patients (74.3%) constituting two groups, one of 253 (prostate cancer), the other of 530 (adenomas = control group). The aim of our study is to evaluate the interest of the PSAL / T ratio in the North African population. The median age of patients was 63 years, 70.3% were symptomatic. The median PSA-T is 6.9ng / ml with a PSAL / T ratio ranging from 7% to 32% with an average of 19%. The mean prostatic volume is 57 cm3. 32, 3% with prostate cancer. The sensitivity and specificity of the PSA L / T ratio according to the cut-offs were studied at the time of diagnosis of prostate cancer and the value of 17% was retained with the best compromise between specificity (68%) and sensitivity (57%). A PSAL / T ratio <15% is the best detection rate for prostate cancer (52%). The contribution of the PSA-L / PSA-T report is indisputable since the first contact with the patient in consultation; the results in the Maghreb are comparable to those found in the literature. This iso PSA form reduces many unnecessary biopsies when it is greater than 25%.