ハイリスク前立腺癌に対する術前8ヵ月ネオアジュバント内分泌療法の有用性に関する検討

Abstract

To evaluate the clinicopathological outcomes of 8 months of neoadjuvant hormonal therapy (NHT) prior to radical prostatectomy for high-risk prostate cancer. A multi-institutional prospective trial was performed between July 2000 and May 2003 involving high-risk prostate cancer patients without metastasis, including 21 who received 8 months of NHT before radical prostatectomy. High-risk group was defined as clinical stage > or =T2c and/or prostate-specific antigen (PSA) >20 ng/ml and/or Gleason score > or =8. PSA values were considered elevated (biochemical failure) if values of 0.1 ng/ml or greater were obtained. Median of initial PSA levels before prostate biopsy was 27.6 ng/ml (8.5-80.7 ng/ml), and median of pre-operative PSA levels after NHT was 0.28 ng/ml (0.02-4.2 ng/ml). There were 5 patients (23.8%) with lower limit of PSA detection (less than 0.02 ng/ml) in 8 months after NHT. The clinical T stage was T1c in 9 patients (42.9%), T2a-b in 8 patients (38.1%), T2c in 3 patients (14.3%), and T3a in 1 patient (4.8%). The median follow-up was 25 months (range 4 to 37). There were 2 patients (9.5%) in pT0, 5 patients (23.8%) with positive surgical margin, 5 patients (23.8%) with extracapsular extension (ECE) and 3 patients (14.3%) with seminal vesicle involvement (SVI). Biochemical failure was occurred in 9 of 21 (42.9%) including of one pT0. Range of time to postoperative biochemical failure was 2 to 25 months (median 6 months) and most of biochemical failure was found within 12 months after surgery. Biochemical failure rate was significantly higher in patient with positive SVI (p = 0.0308) and higher in patients with pre-operative PSA levels of more than 0.1 ng/ml (p = 0.0836), positive ECE (p = 0.0545) and positive surgical margin (p = 0.0545). Biochemical failure was frequent after this combined treatment, even in a pT0 case. Long-term follow-up of patients is needed to assess the impact of this therapy on mortality.