[Biochemical control after conformal, 3 dimensional radiotherapy of prostatic carcinoma].

BACKGROUND: To evaluate biochemical control after 3-D radiation therapy of prostate cancer.

PATIENTS AND METHODS: 180 patients with a median follow-up of 30.5 months (12-67 months) were evaluated. Median dose to the prostate was 70 Gy. 72% of the patients received short-term neoadjuvant hormonal therapy and 28% received radiation therapy alone. Biochemical failure was defined according to the ASTRO consensus criteria.

RESULTS: Pre-treatment PSA levels were higher for patients with combined therapy as compared to radiation alone (median: 13.5 ng/ml vs. 8.8 ng/ml, p = 0.003). Biochemical no-evidence of disease (bNED) survival for all patients was 73% at 3 years. In univariate analysis the following factors were predictive for bNED survival: pre-treatment PSA (< or = 20 ng/ml vs. > 20 ng/ml; 3-years bNED 82% vs. 49%; p < 0.001); age (< 72 years vs. > or = 72 years; 3-years bNED 69% vs. 78%; p = 0.049); tumor differentiation (grade 1 vs. grade 2 vs. grade 3; 3-years bNED 89% vs. 74% vs. 46%; p = 0.002); PSA-nadir value (< or = 0.5 ng/ml vs. > 0.5 ng/ml; 3-years bNED 84% vs. 51%; p < 0.001); time to PSA-nadir (< or = 12 months vs. > 12 months; 3-years bNED 66% vs. 82%; p = 0.04). There was a trend to a lower bNED survival in patients with T3/T4 disease (T1/T2 vs. T3/T4; 3-years bNED 80% vs. 60%; p = 0.059). Neoadjuvant hormonal therapy or dose to the prostate had no significant impact on bNED survival. In multivariate analysis pretreatment PSA, tumor differentiation, PSA-nadir, time to PSA-nadir and age were independent prognostic factors.

CONCLUSIONS: Despite of having higher initial PSA-values patients treated with conformal radiotherapy and short-term neoadjuvant hormonal therapy had the same bNED survival as patients treated with conformal radiotherapy alone. Patients with initial PSA values above 20 ng/ml, with T3 or T4 disease or with poorly differentiated tumors had a low biochemical control. For this group of patients intensified therapy should be considered.