Impact of PSMA PET/CT on the therapeutic decision of Prostate Carcinoma Biochemical Recurrence: a retrospective analysis at the Brazilian public health service.

Abstract

Abstract Background. Prostate cancer (PCa) is the most common malignant tumor in males and biochemical relapse (BCR) consists of a challenging scenario compared to primary staging due to small volume of disease and low PSA levels. Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) presents superior performance and strongly affects therapeutic choice. Objective. The objective of this study was to evaluate the impact of PSMA PET, compared to conventional imaging methods, on BCR therapeutic approach in patients treated at the public Brazilian health system. Methods. 128 patients diagnosed with BCR were evaluated using PSMA after conventional imaging. Disease extension defined by PET was compared with conventional imaging; staging / extension changes and therapeutic management impact were then determined. PET comparison with conventional imaging and decision-making changes were analyzed using descriptive statistics and statistical tests. Results. Disease detection rate was 60% and 41% using PSMA and conventional exams, respectively. PET detection rates and sensitivity increased proportionally to the increase in PSA levels and no statistically significant difference was observed in the rate of disease detection between patients with and without androgen blockade. After disclosure of PET findings and the results of the confrontation with conventional imaging, the board changed the management decision in 36% of the patients with and locoregional treatment indication was predominant. Conclusions. The impact of PSMA on BCR therapeutic management, when compared to conventional exams, is significant, favoring the indication of locoregional salvage treatments and PSMA cost-effectiveness over traditional investigation has been demonstrated in other countries.