“Liquid biopsy by prostate-derived tumor cells enriched from seminal fluid: the semen prostate cancer elements (SPECTRE) project”: this is the title of the study recently presented in San Francisco at the annual Congress of the American Urological Association (AUA 2018, 18-21 May) and published in abstract form in the Journal of Urology. The study was coordinated by Professor Giorgio Guazzoni, Head of Urology and Andrology in Humanitas and by Dr. Massimo Lazzeri of the Urology department at Humanitas and involved the Department of Genetics of Professor Stefano Duga and the Department of Pathological Anatomy directed by Professor Massimo Roncalli.

There is great interest in the use of liquid biopsy for the diagnosis of a neoplasm. Liquid biopsy is a minimally invasive technique that seeks the presence of neoplastic cells in biological fluids (especially in the blood). However, at the moment, as far as primary diagnosis is concerned, although liquid biopsy is the subject of research on several fronts, there is no certainty that it can replace tissue biopsy. Liquid biopsy currently appears to play a clinical role in patients with metastatic disease who undergo chemotherapy to assess response to therapy.


Biopsy on seminal fluid: the great novelty in the study of Humanitas

The study, the result of a multidisciplinary and translational collaboration between different departments operating in Humanitas, brings a great novelty to the scenario of the diagnosis of prostate cancer by exploiting the liquid biopsy. Prostatic biopsy remains an invasive and necessary procedure to reach a diagnosis of tumor, it is carried out by trans-rectal or trans-perineal method and consists in different samplings of small collections of prostate tissue, which are then analyzed for the presence of neoplastic cells.

The great novelty, not previously investigated by anyone, lies in the fact that the team coordinated by Prof. Guazzoni used seminal fluid, produced 30-40% from the prostate, as a liquid biopsy, assuming that it can contain prostatic neoplastic cells in patients with cancer. In this study the seminal fluid of some patients with prostate cancer (who had previously undergone tissue biopsy) was collected; the liquid underwent a sophisticated purification process before proceeding internally to search for any abnormal cells of prostate origin. The abnormality of the cells does not mean that they are necessarily cancer, but in this case the working group knew that the patients had prostate cancer and therefore they “genetically” compared the cells found in the seminal fluid with those extracted from the tumor itself after the surgery of radical prostatectomy, verifying their concordance.


The conclusions

The results obtained are preliminary but very promising and the study was presented at the annual meeting of American urologists. The hope is that the biopsy performed on the seminal fluid can revolutionize the diagnosis of prostate cancer, making it minimally invasive.