Detection performance of Al 18F-PSMA-BCH PET/CT in early relapsed prostate cancer after radical prostatectomy / 中华核医学与分子影像杂志

ABSTRACT

Objective:To assess the performance of Al 18F-prostate specific membrane antigen (PSMA)-BCH PET/CT in the detection and localization of early recurrent prostate cancer after radical prostatectomy. Methods:From July 2021 to July 2022, a cohort of 51 patients (age 49-80(64.8±6.9) years) who underwent Al 18F-PSMA-BCH for biochemical recurrence with the prostate specific antigen (PSA) level less than 2 μg/L in Peking University Cancer Hospital & Institute were retrospectively analyzed. The patients were stratified into 4 groups (PSA<0.2 μg/L, 0.2 μg/L≤PSA<0.5 μg/L, 0.5 μg/L≤PSA<1 μg/L, 1 μg/L≤PSA<2 μg/L groups) according to different PSA levels. Lesions detected by Al 18F-PSMA-BCH PET/CT were recorded as prostate bed (including bed of seminal vesicles); pelvic, paraaortic, mediastinal/supraclavicular and axillary lymph nodes; bone lesions and visceral lesions. The detection rates among different groups were compared by Fisher exact test. Results:Of 51 patients, 30(58.8%) had evidence of abnormal uptake suggestive of recurrent prostate cancer, with 60.0%(18/30) had disease confined to the pelvis, including 26.7%(8/30) had prostate bed recurrence, 26.7%(8/30) had pelvic lymph nodes, 6.6%(2/30) had prostate bed recurrence with pelvic lymph nodes, while 40.0%(12/30) had extra pelvic disease. The detection rates of Al 18F-PSMA-BCH PET/CT in PSA<0.2 μg/L, 0.2 μg/L≤PSA<0.5 μg/L, 0.5 μg/L≤PSA<1 μg/L and 1 μg/L≤PSA<2 μg/L groups were 39.1%(9/23), 6/11, 8/9 and 7/8, respectively. There were no significant differences of detection rates between PSA<0.2 μg/L group and 0.2 μg/L≤PSA<0.5 μg/L group ( P=0.397) and also between 0.5 μg/L≤PSA<1 μg/L group and 1 μg/L≤PSA<2 μg/L group ( P=0.929). Conclusion:Al 18F-PSMA-BCH has a high detection rate for early recurrent prostate cancer, even at low PSA levels less than 0.2 μg/L.