Objetivo Avaliar os valores de PSA nadir (PSAn) dois anos após braquiterapia e sua relação com a taxa de recidiva bioquímica. Materiais e Métodos Cento e vinte pacientes foram tratados no período de janeiro de 1998 a agosto de 2007. Todos os pacientes foram submetidos a braquiterapia isolada. Os resultados foram analisados com base na definição de recidiva bioquímica do Consenso Phoenix. Resultados Oitenta e seis pacientes (71,7%) tiveram controle bioquímico e 34 (28,3%) apresentaram recidiva bioquímica. O PSAn médio foi 0,53 ng/ml. O seguimento médio foi 98 meses. Os pacientes foram divididos em dois grupos: grupo 1, com PSAn < 0,5 ng/ml dois anos após a braquiterapia (74 pacientes; 61,7%), e grupo 2, com PSAn ≥ 0,5 ng/ml dois anos após a braquiterapia (46 pacientes; 38, 3%). O grupo 1 teve recidiva bioquímica em 15 pacientes (20,3%) e o grupo 2 em 19 pacientes (43,2%) (p < 0,02). A análise da sobrevida livre de doença bioquímica de sete anos, estratificada pelos dois grupos, apresentou valores de 80% e 64% (p < 0,02), respectivamente. Conclusão Os níveis de PSAn ≥ 0,5 ng/ml dois anos após a braquiterapia estão fortemente correlacionados com mau prognóstico. Este fato pode ajudar a identificar pacientes com risco de recidiva da doença.

Objective To evaluate the relationship between two year PSA nadir (PSAn) after brachytherapy and biochemical recurrence rates in prostate cancer patients. Materials and Methods In the period from January 1998 to August 2007, 120 patients were treated with iodine-125 brachytherapy alone. The results analysis was based on the definition of biochemical recurrence according to the Phoenix Consensus. Results Biochemical control was observed in 86 patients (71.7%), and biochemical recurrence, in 34 (28.3%). Mean PSAn was 0.53 ng/ml. The mean follow-up was 98 months. The patients were divided into two groups: group 1, with two year PSAn < 0.5 ng/ml after brachytherapy (74 patients; 61.7%), and group 2, with two year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%). Group 1 presented biochemical recurrence in 15 patients (20.3%), and group 2, in 19 patients (43.2%) (p < 0.02). The analysis of biochemical disease-free survival at seven years, stratified by the two groups, showed values of 80% and 64% (p < 0.02), respectively. Conclusion Levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly correlated with a poor prognosis. This fact may help to identify patients at risk for disease recurrence.

Objectives: To assess the incidence and clinical parameters that could influence migration of seeds in localized prostate cancer patients treated by stranded versus loose sources by Iodine-125 brachytherapy. Material and Methods: 100 patients were treated from January/1998 until December/2006. Age, PSA, clinical stage, Gleason, prostate volume, number of seeds, activity of radioactive seeds, and dosimetric parameters, such as V100, V150 and D90 were evaluated. Results: Mean follow-up was 79 months (18 - 120. CI 95%: 72 - 85). Overall, 6 of 100 patients experienced seed migration. Seed migration was found in 4/50 (8%) patients using loose seeds and in 2/50 (4%) treated by stranded seeds. Mean value dosimetric parameters for stranded seeds were greater than those for loose seeds (V100(%): 88.7/82, D90(Gy): 149.2/140.3, D90(%): 104.2/93.8, V150 (%): 53.8/47, respectively). No significant difference in migration of seeds was detected between loose and stranded seeds considering age (p = 0.33), PSA (p = 0.391), prostate volume (p = 0.397), activity of radioactive seeds (p = 0.109), number of seeds (p = 0.338), V100 (p = 0.332), although significant differences were measured in the values of D90(% and Gy) (p = 0.022 and 0.011) and V150 (p = 0.023). Conclusions: Seed migration after brachytherapy might occur and it does affect post-implant dosimetry.

OBJECTIVE: To report the seven-year preliminary results of a single-center on brachytherapy with Iodine-125 seeds, used in combination with external beam radiotherapy in selected patients with localized prostate cancer (T1-T2). MATERIALS AND METHODS: All 105 patients treated by brachytherapy with Iodine-125 seeds, from January/1998 to December/2004, were retrospectively analyzed. The prescribed dose was 144 Gy at the periphery of the prostate for isolated brachytherapy, and 110 Gy for the combination with external beam radiotherapy. The external beam radiotherapy dose was 45 Gy, at the prostatic bed. Neoadjuvant hormone therapy was indicated for selected patients, who received luteinizing hormone-releasing hormone (LH-RH) and/or antiandrogens. For definition of biochemical relapse, it was adopted the American Society for Therapeutic Radiology and Oncology consensus. RESULTS: Of the 105 patients treated, 90 were followed for a mean period of 70 months. Biochemical disease control was achieved in 62 (69%) and biochemical recurrence was manifested in 28 (31%). The analysis of each risk group showed biochemical disease control rates of 79%, 71% and 52% in the low, intermediate and high risk groups, respectively. The mean time for biochemical recurrence was 22 months. Genitourinary acute toxicity was classified as grade 0-2 (RTOG) in 88.5% and in 94.2% for the late toxicity (RTOG/EORTC). Gastrointestinal acute toxicity was graded as 0-2 (RTOG) in 100% and in 97.7% for the late morbidity. No grade 5 was detected. CONCLUSIONS: Brachytherapy with Iodine-125 seeds is an effective alternative treatment for early stage prostatic cancer, with good biochemical disease control rates and low to moderate toxicity. The best results were obtained in low and intermediate risk patients.