PT  - JOURNAL ARTICLE
AU  - Chen, Sirong
AU  - Cheung, William
AU  - Leung, Yim Lung
AU  - Cheng, Kam Chau
AU  - Wong, Ka-Nin
AU  - Ho, Chi-Lai
TI  - <sup>11</sup>C-acetate PET/CT for evaluation of PSA relapse post radical prostatectomy
DP  - 2015 May 01
TA  - Journal of Nuclear Medicine
PG  - 512--512
VI  - 56
IP  - supplement 3
4099  - http://jnm.snmjournals.org/content/56/supplement_3/512.short
4100  - http://jnm.snmjournals.org/content/56/supplement_3/512.full
SO  - J Nucl Med2015 May 01; 56
AB  - 512 Objectives To evaluate the added value of 11C-acetate PET/CT to 18F-FDG for the detection of prostate cancer (PCa) recurrence in patients with rising serum prostate specific antigen (PSA) level post radical prostatectomy.Methods From July 2012 to June 2014, patients post radical prostatectomy with PSA relapse (defined as PSA>=0.2ng/mL) and referred for same-day 11C-acetate & 18F-FDG PET/CT were consecutively recruited. Each PET/CT scan was reviewed by 2 nuclear medicine physicians in consensus for the evaluation of metastasis from PCa (pelvic or distant lymph node [LN], or distant organ metastasis). The level of confidence was scored for each scan in terms of tracer avidity (1=mild, 2=moderate, 3=markedly). The correlation between 11C-acetate avidity and serum PSA level was analyzed.Results 54 patients (age range:50~86y, mean=68.6±8.3y) with PSA relapse (range:0.3~26ng/mL, mean=4.3±6.7ng/mL) after radical prostatectomy were evaluated. 18F-FDG PET/CT detected metastatic recurrence in 25/54 (46.3%) patients: 8 in bone, 18 in LN and 1 in peritoneum. Combined 11C-acetate & 18F-FDG PET/CT detected metastases in 37/54 (68.5%) patients, while 12/54 (22.2%) patients were by 11C-acetate only: 5 bone and 9 LN metastases. The incremental diagnostic value of 11C-acetate over 18F-FDG alone was significant (P<0.05). 11C-acetate PET/CT also increased the level of confidence in 4/20 (20%) patients with tumors avid by both tracers. PSA level was significantly higher in 11C-acetate-postive than negative patients (mean=5.9±8.2 vs 2.1±2.4ng/mL, P<0.05). The detection rate of 11C-acetate PET/CT positively correlated with the relapsed PSA level (P<0.05): 38.5% (5/13), 53.3% (8/15), 62.5% (5/8), 71.4% (5/7) and 81.8% (9/11) for PSA<=1, >1~2, >2~3, >3~4 and >4ng/mL, respectively.Conclusions 11C-acetate PET/CT has an incremental value to 18F-FDG alone in enhancing the sensitivity and confidence for detection of PCa recurrence in patients with PSA relapse after radical prostatectomy. The chance for 11C-acetate PET/CT to localize recurrent disease generally increases with higher PSA levels.