THE ROLE OF MAGNETIC RESONANCE OF PROSTATE IN PATIENTS WITH HIGH GRADE PROSTATIC INTRAEPITHELIAL NEOPLASM AND ATYPICAL SMALL ACINAR PROLIFERATION
Men diagnosed with High Grade Prostatic Intraepithelial Neoplasm (HGPIN) and Atypical Small Acinar Proliferation (ASAP) are usually counseled to undergo re-biopsy because of the variable risk of prostate cancer (PCa). Multiparametric Magnetic Resonance of the prostate (mpMRI) may offer an opportunity to verify the specific areas in the prostate and eventually to target subsequent biopsy in this group of patients.
Materials and Methods
In our Centre, we use 1.5 T mpMRI incorporating a 16-channel surface coil. Two dedicated Uro-radiologists evaluated the exams, which included T2-weighted, diffusion weighted and dynamic contrast enhanced imaging. The reports referred to PI-RADS 1.0 scoring system. We retrospectively analyzed the use of mpMRI in monitoring patients with previous diagnosis of HGPIN and ASAP since 2014 up to august 2016. Additionally, we compared our experience with literature data in Pubmed, searching for the key-words: “High Grade Prostatic Intraepithelial Neoplasm”, “Atypical Small Acinar Proliferation”, “Multiparametric Magnetic Resonance”, “prostate” and “Biopsy”.
We identified a total of 10 pts, divided into 3 groups: a) 5 pts with HGPIN, b) 3 with ASAP and c) 2 with ASAP and HGPIN together. The characteristics of the patients were reported in table 1.
According to literature (based on trials conducted with sextant techniques), 40% of men with ASAP are diagnosed with PCA on the first rebiopsy. Because no clinical variables are able to predict which men with ASAP are at higher risk, current guidelines suggest to perform re-biopsy in 3 to 6. PCa is found in the same sextant as original ASAP in 48% to 57% of cases but, in contrast, in the contro-lateral lobe of the prostate in 17%. However, because the exact biopsy location can only be estimated by conventional TRUS guidance, it is strictly operator-dependent. In this context, mpMRI is a promising technique for PCa detection , also because the exam is specifically validated in the setting of active surveillance. Additionally, this cohort of patients lays in the “Grey Zone PSA Level and prior negative biopsy” (PSA 2.5-10 ng/mL).
This preliminary results suggest that mp-MRI could be a valid technique in order to refer or to avoid PBx in patients with diagnosis of HGPIN or ASAP.
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