Writing PET into existence

Excerpt

In this issue of the EJNMMI, a study evaluating a promising new PET tracer for imaging prostate cancer (PCa), ⁶⁸Ga-PSMA (PSMA), is published [1]. The paper deals with a retrospective analysis in 37 patients with biochemical recurrence of PCa who underwent both ¹⁸F-fluoromethylcholine (CHO) and PSMA PET/CT for the purpose of restaging. The aim of the study was to compare the diagnostic performance of the novel tracer with that of CHO. On a patient basis, the detection rates were 70.3 % and 86.5 % for CHO and PSMA, respectively. PSMA also showed a better performance at low PSA values. The authors conclude that PSMA PET/CT can detect PCa relapse and metastasis with significantly improved contrast when compared with CHO PET/CT. This advantage is related to higher tracer uptake by PCa lesions and low background signal, which allow the detection of small lymph node, bone and liver metastases. Although innovative and interesting, this study had some limitations: it was retrospective; few lesions were confirmed by histology; several criteria were used to validate the uptake areas; the results were compared against CHO PET/CT, which was considered as a standard even though this modality is not established; and, finally, the impact on patient management is not discussed. …