Purpose: To investigate the utility of (11)C-acetate positron emission tomography/computed tomography (PET/CT) for staging of bladder cancer and response assessment after neoadjuvant chemotherapy.
Procedures: Seventeen patients underwent (11)C-acetate PET/CT ≤1 month before radical cystectomy (RC) and pelvic lymph node dissection (PLND). Ten patients had undergone neoadjuvant chemotherapy prior to PET. Histopathology from RC and PLND (n = 16) or nodal biopsy (n = 1) served as gold standard.
Results: Eight of 10 residual tumors showed abnormal (11)C-acetate uptake; two cases of residual TiS were false negative, three cases were false positive, and three true negative. Three patients showed true positive uptake in LN. False positive uptake occurred in 14 LN regions secondary to granulomatous disease after prior intravesical Bacillus Calmette-Guerin (BCG) therapy.
Conclusions: (11)C-acetate has good sensitivity for bladder cancer and LN metastases. However, false positive uptake due to inflammation or granulomatous infection can occur, limiting the staging utility of (11)C-acetate after prior intravesical BCG therapy.