Head-to-head Comparison of the Diagnostic Accuracy of Prostate-specific Membrane Antigen Positron Emission Tomography and Conventional Imaging Modalities for Initial Staging of Intermediate- to High-risk Prostate Cancer: A Systematic Review and Meta-analysis.

CONTEXT: Whether prostate-specific membrane antigen positron emission tomography (PSMA-PET) should replace conventional imaging modalities (CIM) for initial staging of intermediate-high risk prostate cancer (PCa) requires definitive evidence on their relative diagnostic abilities. OBJECTIVE: To perform head-to-head comparisons of PSMA-PET and CIM including multiparametric magnetic resonance imaging (mpMRI), computed tomography (CT) and bone scan (BS) for upfront staging of tumour, nodal, and bone metastasis. EVIDENCE ACQUISITION: A search of the PubMed, EMBASE, CENTRAL, and Scopus databases was conducted from inception to December 2021. Only studies in which patients underwent both PSMA-PET and CIM and imaging was referenced against histopathology or composite reference standards were included. Quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) checklist and its extension for comparative reviews (QUADAS-C). Pairwise comparisons of the sensitivity and specificity of PSMA-PET versus CIM were performed by adding imaging modality as a covariate to bivariate mixed-effects meta-regression models. The likelihood ratio test was applied to determine whether statistically significant differences existed. EVIDENCE SYNTHESIS: A total of 31 studies (2431 patients) were included. PSMA-PET/MRI was more sensitive than mpMRI for detection of extra-prostatic extension (78.7% versus 52.9%) and seminal vesicle invasion (66.7% versus 51.0%). For nodal staging, PSMA-PET was more sensitive and specific than mpMRI (73.7% versus 38.9%, 97.5% versus 82.6%) and CT (73.2% versus 38.5%, 97.8% versus 83.6%). For bone metastasis staging, PSMA-PET was more sensitive and specific than BS with or without single-photon emission computerised tomography (98.0% versus 73.0%, 96.2% versus 79.1%). A time interval between imaging modalities >1 month was identified as a source of heterogeneity across all nodal staging analyses. CONCLUSIONS: Direct comparisons revealed that PSMA-PET significantly outperforms CIM, which suggests that PSMA-PET should be used as a first-line approach for the initial staging of PCa. PATIENT SUMMARY: We reviewed direct comparisons of the ability of a scan method called PSMA-PET (prostate-specific membrane antigen positron emission tomography) and current imaging methods to detect the spread of prostate cancer outside the prostate gland. We found that PSMA-PET is more accurate for detection of the spread of prostate cancer to adjacent tissue, nearby lymph nodes, and bones.

The role of surgery for loco-regional and advanced urological cancers.

PURPOSE OF REVIEW: There is a general misconception that surgery is the antithesis of palliation. However, symptom mitigation, the basic tenet of palliative interventions, can be achieved by invasive procedures. Surgical care, thus, plays an important role in palliative oncology, alongside radiation and systemic therapy. There is global movement to improve palliation in oncology, and thus it is timely to evaluate the role of surgical interventions can play in this setting. RECENT FINDINGS: Many of the surgical interventions done with palliative intent were first established as curative options. Most studies looked at interventions for local control of primary tumour including extirpative surgeries, while some studies studied pain relief for bone metastases. Results show that patients have an acceptable survival outcome and complication rate comparable to those done in the curative setting. However, not all studies report functional outcomes and symptom-relief consistently, highlighting an unmet need. SUMMARY: More studies are needed to further define the role of surgery in palliative care. Randomized controlled trials studying surgical intervention in the palliative setting will be challenging because of lack of equipoise, inherent bias in patient and disease characteristics in those who undergo surgery. Nonetheless, studies should endeavour to study symptom-free survival and PROMs as meaningful endpoints of interventions performed in a palliative setting rather than solely focus on hard oncological endpoints of survival.