Gleason score or pretreatment PSA level
Sunday, July 20th, 2008The authors did not demonstrate any difference between the two isotopes and 3DCRT in biochemical no evidence of disease (bNED) control and concluded that there were no observed advantages for either I-125 and Pd-103 based on Gleason score or pretreatment PSA level. Results with brachytherapy monotherapy or as a boost following EBRT With longer follow-up, more data are available that demonstrate the efficacy of bNED control rates for prostate brachytherapy using I-125 and Pd-103 in well-selected individuals. Ragde et al treated 147 patients with T1–T2 prostate adenocarcinoma using I-125 monotherapy. The overall 10-year bNED control rate was 66%. Multiple other studies [9,20,25,26] have demonstrated that brachytherapy alone is a viable option for treatment of localized prostate cancer in appropriately selected individuals. The most troubling side effects include urethral and bladder symptoms such as irritative voiding (urgency, frequency, and dysuria) and obstructive patterns (hesitancy, decreased force of stream, straining, and urinary retention). Grade 2 acute urinary morbidity occurs in 20% to 40% of patients, many of who may be found to have some degree of baseline urinary dysfunction, whereas more serious grade 3 urinary morbidity occurs in less than 10% of patients [3,27,28]. Although rectal symptoms tend to be more mild following brachytherapy, impotence remains a potential long-term complication [29–33]. As with most forms of local radiation therapy (RT), the risk of these side effects is related to factors that predict urinary morbidity and sexual dysfunction including prostate volume, baseline urinary function measured by a validated toxicity scale, number of seeds or needles, baseline sexual function measured by a validated toxicity scale, and radiation dose to the penile bulb or corporeal bodies. Significant controversy exists with regard to the appropriate use of LDR monotherapy for the treatment of patients with high-risk or locally advanced disease. The role of androgen suppression and EBRT in combination with prostate brachytherapy also is not fully defined. The rationale behind the use of neoadjuvant and adjuvant androgen suppression is twofold. First, the short-term use of neoadjuvant androgen suppression may reduce local tumor burden in preparation for definitive radiotherapy [34] and may radiosensitize the cells to the effects of radiotherapy [35], although there is significant debate on this latter point. Additionally, the prolonged use of adjuvant androgen suppression may control systemic disease outside of the radiation field, although radiobiologic data supporting this have not been demonstrated in brachytherapy patients. 738 E.M. Horwitz et al / Urol Clin N Am 30 (2003) 737–750 In the 1980s, the Radiation Therapy Oncology Group (RTOG) developed adjuvant hormone trials, based on information from earlier studies, which incorporated new hormonal agents with less cardiovascular toxicity. RTOG 85-31 examined the role of long-term hormones (LTH) in combination with EBRT. This study randomized 945 analyzable patients with T1–2 N1 M0, T3 N0–1 M0, or pT3 N0–1 M0 disease between EBRT and long-term monthly hormones (H) with goserelin acetate or RT alone with goserelin given at the time of relapse. Lawton et al [36] reported the 8-year update of this trial, and significant differences between the two treatment arms for bNED control (RT + H versus RT alone, P < 0.0001), distant failure (RT + H versus RT alone, P < 0.0001), and local failure (RT + H versus RT alone, P < 0.0001) were observed. Eight-year distant failure rates were 27% and 37% and 8-year local failure rates were 23% and 37%, respectively. A subset analysis revealed significant differences in overall and cancerspecific survival for patients with centrally reviewed Gleason score 8–10 tumors [36]. Bolla et al [37] reported data from the second trial involving LTH and EBRT. The European Organization for the Research and Treatment of Cancer (EORTC) trial included 415 patients randomized between EBRT alone (70 Gy) and EBRT with goserelin starting the first day of treatment and continuing for 3 years posttreatment. The authors reported a statistically significant improvement in overall survival (P < 0.001). Five-year overall survival rates were 79% and 67%, respectively, for the two groups (P < 0.001) [37]. The RTOG addressed the issue of short-term hormonal ablation in the companion study to 85- 31. RTOG 86-10 randomized patients with locally advanced T2b–4 N0–1 M0 prostate cancer between goserelin and flutamide 2 months before and during EBRT versus RT alone.