474 The role of transrectal ultrasound (trus) and serum PSA for clinical evaluation of radical radiotherapy (RT) in localized prostatic cancer

Between l/’93 and 12/’94, 50 patients with clinically localized (11–3,Nx,M0) prostatic adenocarcinoma histologically confirmed, were submitted to RT at our Department. Gleason Pattern Score averaged 5 (range 2–9). Digital rectal examination, TRUS, TC or MR of the pelvis, radioisotope bone scan and measurement of serum PSA were performed for clinical staging, RT was delivered to the prostatic grand only, using 18 MV linear accelerator and a rotational technique. Total dose was 68–70 Gy (200 cGy/day 5 days/week) in continuous course. TRUS and PSA were repeated at 6 months after the end of the irradiation for clinical evaluation of RT effectiveness. At the present, 21 patients have a follow-up longer than six months. In 8/21 cases RT followed an hormonal therapy (OT) whereas 3/8 patients prolonged OT during RT 11/21 patients had a lesion confirmed by TRUS before RT start and 10/11 showed no dimensional modification at the follow-up. 8/21 showed a reduction of the prostatic volume > 10%. Pre-RT mean PSA was 6.4 ng/ml (range 0.1–19.4 ng/ml) versus 1.6 ng/ml (0.1–5.4 ng/ml) at the follow-up, six months after the end of RT. The role of TRUS for the detection of local relapses is undisputed. On the other hand, PSA is a good index to evaluate clinical response to treatment.