Digital Rectal Examination Is Not a Useful Screening Test for Prostate Cancer

Mesenchymal stem cell-derived exosomes for management of prostate cancer: An updated view

Prostate cancer represents the second most prevalent form of cancer found in males, and stands as the fifth primary contributor to cancer-induced mortality on a global scale. Research has shown that transplanted mesenchymal stem cells (MSCs) can migrate by homing to tumor sites in the body. In prostate cancer, researchers have explored the fact that MSC-based therapies (including genetically modified delivery vehicles or vectors) and MSC-derived exosomes are emerging as attractive options to improve the efficacy and safety of traditional cancer therapies. In addition, researchers have reported new insights into the application of extracellular vesicle (EV)-MSC therapy as a novel treatment option that could provide a more effective and targeted approach to prostate cancer treatment. Moreover, the new generation of exosomes, which contain biologically functional molecules as signal transducers between cells, can simultaneously deliver different therapeutic agents and induce an anti-tumor phenotype in immune cells and their recruitment to the tumor site. The results of the current research on the use of MSCs in the treatment of prostate cancer may be helpful to researchers and clinicians working in this field. Nevertheless, it is crucial to emphasize that although dual-role MSCs show promise as a therapeutic modality for managing prostate cancer, further investigation is imperative to comprehensively grasp their safety and effectiveness. Ongoing clinical trials are being conducted to assess the viability of MSCs in the management of prostate cancer. The results of these trials will help determine the viability of this approach. Based on the current literature, engineered MSCs-EV offer great potential for application in targeted tumor therapy.

Comparing the Performance of Digital Rectal Examination and Prostate-specific Antigen as a Screening Test for Prostate Cancer: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Although digital rectal examination (DRE) is recommended in combination with prostate-specific antigen (PSA) for detection of prostate cancer (PCa), there are limited data to support its use as a screening/early detection test. Our objective was to assess the diagnostic value of DRE in screening for early detection of PCa.

METHODS

In August 2023, we queried the PubMed, Scopus, and Web of Science databases to identify prospective studies simultaneously investigating the diagnostic performance of DRE and PSA for PCa screening. The primary endpoints were the positive predictive value (PPV) and cancer detection rate (CDR) of DRE. Secondary endpoints included the PPV and CDR of both PSA alone and in combination with DRE. We conducted meta-regression analysis to compare the CDR and PPV of different screening strategies. This meta-analysis is registered on PROSPERO (CRD42023446940).

KEY FINDINGS AND LIMITATIONS

We identified eight studies involving 85 738 participants, of which three were randomized controlled trials and five were prospective diagnostic studies, that reported the PPV and CDR of both DRE and PSA for the same cohort. Our analysis revealed a pooled PPV of 0.21 (95% confidence interval [CI] 0.13-0.33) for DRE, which is similar to the PPV of PSA (0.22, 95% CI 0.15-0.30; p = 0.9), with no benefit from combining DRE and PSA (PPV 0.19, 95% CI 0.13-0.26; p = 0.5). However, the CDR of DRE (0.01, 95% CI: 0.01-0.02) was significantly lower than that of PSA (0.03, 95% CI 0.02-0.03; p < 0.05) and the combination of DRE and PSA (0.03, 95% CI 0.02-0.04; p < 0.05). The screening strategy combining DRE and PSA was not different to that of PSA alone in terms of CDR (p = 0.5) and PPV (p = 0.5).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Our comprehensive review and meta-analysis indicates that both as an independent test and as a supplementary measure to PSA for PCa detection, DRE exhibits a notably low diagnostic value. The collective findings from the included studies suggest that, in the absence of clinical symptoms and signs, DRE could be potentially omitted from PCa screening and early detection strategies.

PATIENT SUMMARY

Our review shows that the screening performance of digital rectal examination for detection of prostate cancer is not particularly impressive, suggesting that it might not be necessary to conduct this examination routinely.

A Rare Case of Neuroendocrine Prostate Cancer Detected on 68Ga - DOTANOC Positron Emission Tomography/Computed Tomography (PET/CT)

Prostate cancer is one of the most common malignancies affecting elderly men worldwide and the fifth leading cause of cancer death in men. Prostate cancer includes many histological variants with the prostatic acinar adenocarcinoma variant accounting for the majority of the diagnosed cases. Other less common histological variants are broadly classified as non-acinar carcinomas. One of the non-acinar carcinoma variants is neuroendocrine prostate cancer (NEPC). NEPC can emerge as a mechanism of treatment resistance in castration-resistant conventional prostate cancer and can also rarely be seen as a primary histological form at the time of initial diagnosis. Like other non-acinar carcinoma variants of prostate cancer, NEPC is also an aggressive variant with associated poor prognosis. Neuroendocrine tumors (NETs) are characterized by the expression of somatostatin receptors (SSTRs). Positron emission tomography/computed tomography (PET/CT) using radiolabeled somatostatin analogs like DOTANOC have been used to detect and stage these NETs. These radiolabeled somatostatin analogs also provide the option of treatment of these tumors and have been used in peptide receptor radionuclide therapy of these tumors. NEPC being a neuroendocrine malignancy also expresses SSTRs and hence can be detected with PET/CT radiotracers like 68Gallium-labeled somatostatin analogs. We here report a case of metastatic treatment-emergent NEPC detected on 68Ga - DOTANOC PET/CT.