Inzidentalome in der Prostataspezifischen-Membranantigen- Positronenemissionstomographie/ Computertomographie – Auftreten, Charakterisierung und klinische Relevanz

Purpose Due to the limited scientific data of unexpected findings (incidentalomas) in PSMA-PET/CT, it was our objective to analyse PSMA-PET/CT results regarding the incidence und clinical relevance of incidental findings to contribute to the improvement of clinical management. Key objectives included the overall frequency of occurrence in different organs, the detection rate of 68Ga-PSMA-positive incidentalomas and the clinical relevance. Considering recent indications of 68Ga-PSMA-uptake in other malignancies other than prostate cancer, it was our goal to investigate cases that support or contradict that observation. Methods In a retrospective approach we reviewed medical records of 392 patients undergoing a PSMA-PET/CT scan between January 2014 and January 2019 at university hospital Marburg. All 486 PSMA-PET/CT scan results were searched for incidental findings, which were then classified in terms of expected dignity: benign or unclear/ suspicious. To determine the entity, all incidental findings were reviewed with a specialist for nuclear medicine and information on follow-up examinations, including follow-up-imaging and histopathology was gathered. Results After reviewing all incidental findings with a specialist for nuclear medicine we identified 223 incidental findings in 486 PSMA-PET/CT-scans, of which 49 (22%) were classified as suspicious. Most frequently affected were the kidneys (31,4%), liver (29,1%) and lung (19,7%). Suspicious incidental findings were found in 10 % of scans and mostly detected in the lung. 17 (7,6%) findings showed 68Ga-PSMA-uptake. Follow-up information was available in 47% of cases. Four second cancers were detected, including a colon adenocarcinoma, a pulmonary adenocarcinoma, a pancreatic neoplasia and a papillary thyroid cancer.