‘Prostatic Evasive Anterior Tumours’: The Role Of Magnetic Resonance Imaging
31 Jan 2010
UroToday.com – In this recent article, we review our experience and delineate the role of magnetic resonance imaging (MRI) in identifying patients presenting with a raised prostate-specific antigen (PSA) level and clinical findings suggestive of anterior predominant tumors, which appear to be significant, particularly in those with a previous negative biopsy or low-volume disease undergoing active surveillance (AS). 
We previously highlighted the important role of MRI in assisting in the detection of prostate cancer (CaP) in men with previous negative biopsies and elevated prostate-specific antigen levels.  (also this article appears in Urotoday please insert reference) Furthermore, anterior tumors have been identified and concerns raised regarding the ability to adequately biopsy such lesions as they are not identifiable on digital rectal exam or with most biopsy schemes with invasive methods often utilized to confirm their existence. [3-5] In marrying these two concepts, It was first suggested in Europe by Zerbib and colleagues  that MRI may be helpful in identifying anterior tumors in men with CaP.
Although a retrospective study, our database is comprehensive and was able to identify patients with anteriorly predominant tumors on MRI whom had undergone prostate biopsy. MRI had a positive predictive value for anterior tumors of 87% (27/31). In many of the cases, serious adverse pathological features were noted, particularly in those proceeding to radical prostatectomy.
Furthermore, highlighting the importance of anterior prostate tumors, was the recent article by Duffield et al.  regarding AS for CaP, which appeared in the Journal of Urology. In this article, for men on AS, the difficulty in recognizing and biopsying anterior tumors was stressed. However, the role of imaging was not discussed and our results confirm that imaging is extremely important in selected men.  Although not advocating MRI in all patients on AS, we believe there is a subset of patients either having negative TRUS biopsy or low volume disease undergoing AS who should be considered for MRI and further biopsy as their pathology may be aggressive.
PEATS, standing for “prostate evasive anterior tumor syndrome,” appears to be appropriate in describing men with anterior tumors not palpable at DRE nor accessible by standard biopsy schemes. So our summary is that where discrepancy between PSA, PSA dynamics and either a negative biopsy or low volume prostate cancer managed by AS, think of anterior tumors and think of MRI. Our perspective is that these tumors are actually fairly aggressive and urologists and all physicians should be aware of their potential behaviour. Certainly, this requires further analysis in a large prospective study with particular investigation of the specific triggers for MRI and targeted biopsies which we are now undertaking at our institution.
I stated in my book that a negative biopsy was a good thing on two fronts. One, the biopsy did not show cancer, and two, it means most probably that you won’t get the bad kind. Bad kind meaning, high volume and high Gleason’s score path report. In my twenty-four year career, I have seen only one time a Gleason’s eight on a repeat biopsy of a gland with a previously negative biospy. I believe this case of mine represts a case similiar to what is decsribed above. In the second biopsy, which was about three years afer the first, there was one small focus of the Gleason’s eight. The patient is in his mid seventies and after evaluation by the radiation therapist , has elected to pursue radiation. I don’t think this situation occurs often, but I like the idea of considering it if there is a negative biopsy, a rising PSA, and concern that something is going but you are unable to confirm it.
This patient, Mr. Gaines, is a friend of mine and I have several of his friends as patients as well. Before Mr. Gaines first biopsy a friend of his had told him that I had done a biopsy on him and it was essentially painless. Unfortunately the I.V. meds we gave Mr. Gaines did not do much for him and he had much more pain with the biopsy than was intimated by his friend. When I asked how the biopsy went, he said, ” I’m gonna find my friend who said this would not hurt and whip his a..” About a year later the friend that had told Mr. Gaines that the biopsy would be painless, needed to have cystoscopy, another potentially painful thing I do to people. We gave this patient I.V. versed and proceeded with the procedure and he too unfortunately experienced more pain that I or he would have preferred. He also commented that the shot had done nothing to him and wondered if my nurse had hit the vien at all. A month later, he developed an issue that required another cystoscopy and when I recommended it he rightfully questioned the aneshesia that he would be getting. “I ain’t gonna do it if all I get is a “Gaines” shot. Now all of Mr. Gaines friends, and I see alot of them, begin any discussion of a procedure with the admonition,”You aren’t going be giving me a “Gaines” shot are you?”