Transperineal prostate brachytherapy, using I-125 seed with or without adjuvant androgen deprivation, in patients with intermediate-risk prostate cancer: study protocol for a phase III, multicenter, randomized, controlled trial

The optimal protocol for ¹²⁵I-transperineal prostatic brachytherapy (TPPB) in intermediate-risk prostate cancer (PCa) patients remains controversial. Data on the efficacy of combining androgen-deprivation therapy (ADT) with ¹²⁵I-TPPB in this group remain limited and consequently the guidelines of the American Brachytherapy Society (ABS) provide no firm recommendations.

Seed and Hormone for Intermediate-risk Prostate Cancer (SHIP) 0804 is a phase III, multicenter, randomized, controlled study that will investigate the impact of adjuvant ADT following neoadjuvant ADT and ¹²⁵I-TPPB. Prior to the end of March, 2011, a total of 420 patients with intermediate-risk, localized PCa will be enrolled and randomized to one of two treatment arms. These patients will be recruited from 20 institutions, all of which have broad experience of ¹²⁵I-TPPB. Pathological slides will be centrally reviewed to confirm patient eligibility. The patients will initially undergo 3-month ADT prior to ¹²⁵I-TPPB. Those randomly assigned to adjuvant therapy will subsequently undergo 9 months of adjuvant ADT. All participants will be assessed at baseline and at the following intervals: every 3 months for the first 24 months following ¹²⁵I-TPPB, every 6 months during the 24- to 60-month post-¹²⁵I-TPPB interval, annually between 60 and 84 months post-¹²⁵I-TPPB, and on the 10th anniversary of treatment.

The primary endpoint is biochemical progression-free survival (BPFS). Secondary endpoints are overall survival (OS), clinical progression-free survival, disease-specific survival, salvage therapy non-adaptive interval, acceptability (assessed using the international prostate symptom score [IPSS]), quality of life (QOL) evaluation, and adverse events. In the correlative study (SHIP36B), we also evaluate biopsy results at 36 months following treatment to examine the relationship between the results and the eventual recurrence after completion of radiotherapy.

These two multicenter trials (SHIP0804 & SHIP36B) are expected to provide crucial data regarding the efficacy, acceptability and safety of adjuvant ADT. SHIP36B will also provide important information about the prognostic implications of PSA levels in intermediate-risk PCa patients treated with ¹²⁵I-TPPB.

NCT00664456, NCT00898326, JUSMH-BRI-GU05-01, JUSMH-TRIGU0709