Accuracy of 3 Tesla pelvic phased-array multiparametric MRI in diagnosing prostate cancer at repeat biopsy

Pietro Pepe1, Antonio Garufi2, Giandomenico Priolo2, Giuseppe Candiano1, Francesco Pietropaolo1, Michele Pennisi1, Francesco Aragona1
  • 1 Ospedale Cannizzaro - U.O. Urologia (Catania)
  • 2 Ospedale Cannizzaro - Imaging Department (Catania)


Objective. Although the ideal biopsy scheme should perform targeted biopsies to diagnose only significant PCa reducing the number of unnecessary procedures (1), still today, the serum biomarkers and imaging lack in accuracy especially in the early stage of disease. Recently, multiparametric magnetic resonance imaging (mMRI) using pelvic phased -array coil (mpMRI) or endorectal coil (meMRI) has been proposed to improve the detection rate for PCa (2-8) to diagnose significant cancer in patients submitted to repeat biopsy.
In this study, the accuracy of mpMRI to diagnose significant PCa in men who underwent repeat saturation biopsy (SPBx) for persistent suspicion of PCa was prospectively evaluated; in detail, detection for cancer of saturation prostate biopsy was compared with that obtained performing targeted mpMRI-guided biopsy

Methods and results

Methods and results. From June 2011 to December 2013, 168 patients (median 65 years) with negative digital rectal examination underwent repeat transperineal saturation biopsy (SPBx; median 28 cores) (9) for persistently high or increasing PSA values, PSA >10 ng/ml or PSA values between 4.1-10 or 2.6-4 ng/ml with free/total PSA < 25% and < 20%, respectively (10). All patients underwent mpMRI using a 3.0 Tesla scanner equipped with surface 16 channels phased-array coil and lesions suspicious for PCa were submitted to additional targeted biopsies. To ensure that histopatological findings matched with mpMRI images (cognitive fusion) the assessment of radiological images and SPBx scheme were performed dividing the prostate into 14 regions (8); moreover, in the presence of mpMRI lesions suspicious for cancer (PI-RADS score 4 and 5) (11), 3-4 (median 3.5 cores) targeted TRUS guided-biopsies in addition to standard SPBx were performed.
A T1c PCa was found in 66 (39%) cases (median PSA equal to 8.9 ng/mL); SPBx and mpMRI-suspicious targeted biopsy diagnosed 60 (91%) and 52 (78.8%) cancers missing 6 (all of the anterior zone) and 14 cancers (12 and 2 of the lateral margins and anterior zone), respectively; in detail, mpMRI missed 12 (18.1%) PCa charaterized by microfocal (1 positive core with greatest percentage of cancer and Gleason score equal to 5% and 6, respectively) disease at risk for insignificant cancer. The diameter of the suspicious mpMRI lesion was directly correlated to the diagnosis of PCa with poor Gleason score (p <0.05); detection rate of cancer for each suspicious mpMRI core was 35.3%. Diagnostic accuracy, sensitivity, specificity, positive and negative predictive value of mpMRI in diagnosing PCa was 75.7%, 82.5%, 71.8%, 78.9%, 87.9%, respectively.


Discussion. In the last years, mMRI has gained growing importance in PCa diagnosis and staging using mpMRI or meMRI (2-8); recently, 3 Tesla MRI has been suggested in the reevaluation of patients enrolled in active surveillance protocols, and is highly representative of the true GS and predictive of significant PCa. The estimated sensitivity and specificity for PCa detection by MRI varies between 57% and 100% vs 44% and 96%, respectively (3); therefore, there is increasing interest in using MRI, especially in men with prior negative prostate biopsy and persistent suspicion of PCa.
In our series, mpMRI detected 52 out 66 PCa; in detail, mpMRI in comparison with SPBx diagnosed 4 significant cancer of the anterior zone missing 12 cancers charaterized by microfocal biopsy histological disease at risk for insignificant PCa. In addition, a correlation between mpMRI suspicious lesion diameter vs PCa diagnosis and tumour grade was found. Some limitations and considerations of the present study deserve mention. Firstly, we do not know the true diagnostic accuracy of mpMRI in PCa diagnosis because the detection rate for cancer was compared with SPBx results. Secondly, we do not know if the false-positive rate (23.8% of the cases) of mpMRI was secondary to false-negative SPBx results or was biased because an MRI imaging/ultrasound fusion-guided biopsy, theoretically more accurate, was not performed (12).
In conclusion, mpMRI improved SPBx accuracy in diagnosing significant anterior PCa; the diameter of mpMRI suspicious lesion resulted significantly predictive of aggressive cancers.


1) Chun FK, Epstein JI, Ficarra V, Freedland SJ, Montironi R, Montorsi F, Shariat SF, Schröder FH and Scattoni V: Optimizing performance and interpretation of prostate biopsy: A critical analysis of the literature. Eur Urol 2010; 58: 851-864.
2) Quentin M, Biondin D, Klasen J, Schek J, Buchbender C, Miese FR, Miese FR, Antoch G, Barski D, Albers P and Arsov C: Evaluation of a structured report of functional prostate magnetic resonance imaging in patients with suspicion for prostate cancer or under active surveillance. Urol Int 2012; 89: 25-29.
3) Hambrock T, Hoeks C, Hulsbergen-van de Kaa C, Scheenen T, Fütterer J, Bouwense S, van Oort I, Schröder F, Huisman H and Barentsz J: Prospective assessment of prostate cancer aggressiveness using 3-T diffusion-weighted magnetic resonance image-guided biopsies versus systematic 10-core transrectal ultrasound prostate biopsy. Eur Urol 2012; 61: 177-184.
4) Turkbey B, Shah VP, Pang Y, Bernardo M, Xu S, Kruecker J, Locklin J, Baccala AA Jr, Rastinehad AR, Merino MJ, Shih JH, Wood BJ, Pinto PA and Choyke PL: Is apparent diffusion coefficient associated with clinical risk scores for prostate cancers that are visible on 3-T MRI images? Radiology 2011; 488-493.
5) Arsov C, Quentin M, Rabenalt R, Antoch G, Albers P, Blondin D: Repeat transrectal ultrasound biopsies with additional targeted cores according to results of functional prostate MRI detects high-risk prostate cancer in patients with previous negative biopsy and increased PSA – a pilot study. Anticancer Res 2012; 32: 1087-1092.
6) Turkbey B and Choyke PL: Multiparametric MRI and prostate cancer diagnosis and risk stratification. Curr Opin Urol 2012; 22: 310-315.
8) Pepe P, Garufi A, Priolo G, Candiano G, Pietropaolo F, Pennisi M, Fraggetta F, Aragona F: Prostate cancer detection at repeat biopsy biopsy: can pelvic phased-array multiparametric MRI replace saturation biopsy? Anticancer Res 2013; 33: 1195-1199.
9) Pepe P, Aragona F: Saturation prostate needle biopsy and prostate cancer detection at initial and repeat evaluation. Urology 2007; 70: 1131-1135.
10) Pepe P, Aragona F: Incidence of insignificant prostate cancer using free/total PSA: Results of a case-finding protocol on 14,453 patients. Prostate Cancer Prostatic Dis 2010; 13: 316-319.
11) Kuru TH, Roethke MC, Rieker P, Roth W, Fenchel M, Hohenfellner M, Schlemmer HP, Hadaschik BA Histology core-specific evaluation of the European Society of Urogenital Radiology (ESUR) standardised scoring system of multiparametric magnetic resonance imaging (mpMRI) of the prostate. BJU Int 2013; 112: 1080–1087.
12) Mozer P, Rouprêt M, Le Cossec C, Granger B, Comperat E, de Gorski A, Cussenot O, Renard-Penna R: First round of targeted biopsies with magnetic resonance imaging/ultrasound-fusion images compared to conventional ultrasound-guided trans-rectal biopsies for the diagnosis of localised prostate cancer. BJU Int. 2014 Feb 19. doi: 10.1111/bju.12690. [Epub ahead of print]