Contribution of 11C-Choline PET/CT in prostate carcinoma biochemical relapse with serum PSA level below 1 ng/ml

Abstract Objective 11 C-Choline PET/CT has demonstrated good results in the restaging of prostate cancer (PCa) with high serum prostate specific antigen (PSA), but its use in patients with low serum PSA is controversial. Our aim was to evaluate the contribution of 11 C-Choline PET/CT in patients with PCa, biochemical relapse and PSA Material and method Fifty consecutive patients (mean age: 65.9 ± 5.6 years) with biochemical relapse of PCa and serum PSA 11 C-Choline. Minimum follow up time was 30 months. Results Twenty-one out of 50 patients (42%) had an abnormal 11 C-Choline PET/CT. In 7 out of 21 patients (14%) tumour was confirmed (4 in prostatic bed, 4 in pelvic lymph nodes, 2 in mediastinal lymph nodes and one synchronous sigmoid carcinoma), and in all cases the initial therapy planning was modified. In 2 patients (4%) subsequent tests diagnosed benign disease (one sarcoidosis, one tuberculosis sequelae) and in 3 patients (6%) they ruled out pathology. The other 9 patients (18%) had no further assessment (7 mediastinal and 4 pelvic lymph nodes). Twenty-nine out of 50 patients (58%) had a normal PET/CT. At 30 months, follow up recurrence was confirmed in only 2 of these patients. Conclusions 11 C-Choline PET/CT proved its usefulness in demonstrating tumour in 14% of patients with BR of PCa and serum PSA 11 C-Choline PET/CT was associated with a very low rate of recurrence at 30 months.