The results of real-time brachytherapy for the management of low- and intermediate-risk prostate cancer in patients with prostate volumes up to 100 mL

摘要

Study Type - Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Historically, the majority of centres in the UK practise a pre-plan brachytherapy technique which is limited to prostate volumes 50 ml. This study provides further evidence that it is technically possible to deliver a quality implant in a large prostate using real-time brachytherapy and that the treatment is well tolerated. It has emphasized the value of functional parameters in selecting appropriate patients and concluded that prostate volumes up to 100 ml should not exclude patients from brachytherapy. OBJECTIVES To report the results of real-time brachytherapy in the management of low-risk and intermediate-risk prostate cancer in patients with prostate volumes up to 100 mL, over a 6-year period. To prospectively determine whether prostate volume influences the ability to achieve a quality implant and therefore impact upon prostate-specific antigen (PSA) relapse-free survival, and urinary and rectal toxicity. SUBJECTS AND METHODS In all, 216 men with localized prostate cancer were treated with real-time prostate brachytherapy using 125I implants between November 2003 and December 2009. Patient selection was based upon functional parameters; International Prostate Symptom Score (IPSS) and flowmetry. Patients had computed tomography imaging at 1 month to assess post-implant dosimetry. PSA, IPSS and Radiation Therapy Oncology Group rectal toxicity scores were recorded prospectively over the follow-up period. Patients with prostate volumes ≤50 mL and those with volumes 50 mL were compared. RESULTS Overall PSA relapse-free survival was 98.8%; 97.0% for intermediate-risk patients and 100.0% for low-risk patients. By volume, 98.5% of men with standard prostates were free from PSA relapse compared with 100.0% of men with large prostates. The mean post-implant D90 was 177.0 Gy; 175.5 Gy in standard prostates and 183.5 Gy in large prostates. The overall acute urinary retention rate was 1.9%; 1.7% in standard prostates and 2.4% in large prostates. There were three urethral strictures, all in the standard prostate group. The mean IPSS increased to 11 and 14 at 3 months for the standard and large prostate groups, respectively, before settling to 2 above baseline for both groups at 12 months. There were no rectovesical fistulae. Persistent rectal bleeding was reported by one (0.5%) patient in the standard prostate group. CONCLUSIONS Prostate brachytherapy is effective in the treatment of low-risk and intermediate-risk prostate cancer. It is technically possible to deliver a quality implant in a large prostate using real-time brachytherapy. The treatment itself is well tolerated. Prostate volumes up to 100 mL should not exclude patients from brachytherapy providing either flow rate ayen14 mL/s or symptom score (IPSS) a;circ 10.