The results of a prospective clinical study, published on Cancers, carried out on 240 samples, have revealed a diagnostic precision of 100% (false positives) and 96% (false negatives). Extending the database will allow us to develop an optimal decision-making procedure for prostate tumours better than any other previously used marker. In fact, the results of this study could revolutionise the clinical management of prostate cancer by allowing a much more efficient secondary prevention activity based on medical and surgical procedures.

“Until today, the dosage of PSA, the dosage of specific prostatic antigen,” explains Prof. Alessandro Sciarra at the Department of Maternal, Infantile and Urological Sciences, “was our fundamental marker for the early diagnosis of prostate cancer. However, it had important limitations in discriminating between malign and benign pathologies of the prostatic gland, which often coexist in the same patient. The PSA level does not necessarily indicate a prostatic tumour, and, on the other hand, there may also be a tumour with values below 4 ng/ml. Our new test employs a simple blood test to characterise and quantify the plasmatic level of exosomes, nano-metric extra-cellular vesicles that express PSA (EXO-PSA) in a more specific manner in case of malign prostate cancer.”

Exosomes, that are released by most cells in our bodies, are used to transport and exchange molecules amongst cells. They are currently considered to be the main source for disease biomarkers. In the case of prostatic cancer, the exosomes transport a form of PSA that is different in many ways from serum-soluble PSA.

By comparing the values of serum PSA with EXO-PSA, the study demonstrates the high value of the test to distinguish prostate cancer from all other conditions, including Benign prostatic hyperplasia, over the PSA level.

“This is an extremely high precision test,” adds Prof. Stefano Fais from the Department of Oncology and Molecular Medicine (Istituto Superiore di Sanità). “It is simple as it does not require any further tests and eliminates the stress related to further testing. Moreover, by eliminating the need for further testing, this test will lead to a decrease in medical expenses.”

Thus, based on the data of this new study, new screening will be availabe for the global male population based on EXO-PSA.

References:

Increased Plasmatic Levels of PSA-Expressing Exosomes Distinguish Prostate Cancer Patients from Benign Prostatic Hyperplasia: A Prospective Study - Logozzi, M. Angelini, D. F. Giuliani, A. Mizzoni, D. Di Raimo, R. Maggi, M. Gentilucci, A. Marzio, V. Salciccia, S. Borsellino, G. Battistini, L. Sciarra, A. Fais, S. Cancers (27 settembre 2019) DOI: https://doi.org/10.3390/cancers11101449

For further information 

Alessandro Sciarra - alessandro.sciarra@uniroma1.it

Stefano Salciccia - stefano.salciccia@uniroma1.it

Department of Maternal, Infantile and Urological Sciences