Management of prostate cancer requires considerable economic and social efforts and may causes some discomfort to patient. To attempt a simplification of the prostate cancer follow-up (dosage of PSA, ultrasound and abdominal and pelvic TC and/or RM, bone scan, X-ray chest and X-ray bone), Authors have review the patients with prostatic cancer who were undergone to a conservative treatment with hormonal and/or radiation therapy. From January 1984 to September 1995, 136 patients have been evaluated in the Urological Department of University of Perugia. Local staging cancer has been made according to TNM system. Ultrasound transrectal follow-up study (TRUS) we made through longitudinal and/or transversal scans. The echographic features have been evaluated are the prostate size, volume and echogenic pattern of cancer, extracapsular extention and, finally, the echographic appearance of surrounding tissues (seminal vesicles, rectum, bladder). In 116 patients (85.3%) Authors found a good correlation of clinical course and the results of the investigations whereas in 20 patients (14.7%) such correlation falls to be demonstrated. Although PSA level remains an important prognostic marker for monitoring patients with prostatic cancer, TRUS is useful to determinate not only the local status but also to predict the subsequent clinical course of these patients. The later could be performed at least twice a year whereas further investigations could be prescribed only in presence of clinical suspicious of metastasis. It can be concluded that TRUS and PSA levels are sufficiently safe indexes on follow-up of prostate cancer which can replace the most expensive examinations avoiding an unnecessary cost to the health care system. Furthermore TRUS can recognize patients with urine flow obstruction who may benefit by treatment with improvement of their quality of life.