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MP48-15 EVALUATING THE CLINICAL UTILITY OF TRANSPERINEAL TEMPLATE PROSTATE MAPPING BIOPSY
THE JOURNAL OF UROLOGYâ
Vol. 193, No. 4S, Supplement, Sunday, May 17, 2015
RESULTS: PCa detection rate was 33.1% (58) and HG-PCa rate 43.1% (25). LS-mMRI was detected in 61 patients (34.9%), ISmMRI in 67 (38.3%) and HS-mMRI in 47 (26.9%). PCa was detected in 6 patients with LS-mMRI (9.8%), 17 with IS-mMRI (25.4%), and 35 with HS-mMRI (74.5%), p<0.001. HG-PCa was detected in 1 patient with LS-mMRI (16.7%), in 4 with IS-mMRI (23.5%), and 14 with HSMRI (40%), p<0.001. Multivariate analysis demonstrated that mMRI was the only independent predictor of PCa, OR: 4.247 (95%CI: 2.182-8.265), however it failed to predict HG-PCa. Establishing the criteria of not rebiopsy patients with LS-mMRI, sensitivity of mMRI was 89.7% (52/58), specificity 47% (55/117), positive predictive value 45.6% (52/114), negative predictive value 90.2% (55/61), rate of avoided biopsies 34.9% (61/175) and rate of non detected PCa 9.8%. The patient with LS-mMRI and HG-PCa (Gleason 4þ4) was subjected to radical prostatectomy and the specimen Gleason score was 3þ4. CONCLUSIONS: mMRI provides useful information to increase the efficiency of standard 12-core TRUS-guided biopsy. Selecting for rPB only those patients with IS or HS-mMRI, more than 30% of rPBs could be avoided with less than 10% probability to lose PCa diagnosis. Source of Funding: none
MP48-13 IDENTIFICATION OF PATHOLOGICALLY FAVORABLE DISEASE IN INTERMEDIATE RISK PROSTATE CANCER PATIENTS: IMPLICATIONS FOR SELECTION OF ACTIVE SURVEILLANCE CANDIDATES Giorgio Gandaglia*, Nazareno Suardi, Marco Bianchi, Nicola Fossati, , Giuseppe Zanni, Milan, Italy; Firas Abdollah, Detroit, MI; Federico Deho Umberto Capitanio, Emanuele Zaffuto, Milan, Italy; Shahrokh F. Shariat, Vienna, Austria; Pierre Karakiewicz, Montreal, Canada; Francesco Montorsi, Alberto Briganti, Milan, Italy INTRODUCTION AND OBJECTIVES: Radical prostatectomy (RP) is associated with excellent outcomes in patients with intermediate-risk Prostate Cancer (PCa). However, this group represents a heterogeneous category. We aimed at identifying predictors and developing a novel model for the identification of pathologically favorable PCa among patients with intermediate-risk disease. METHODS: Overall, 950 patients with intermediate-risk PCa according to D’Amico criteria treated with RP lymph node dissection at a single center between 2006 and 2014 were identified. Pathologically favorable PCa was defined as the presence of pathologic Gleason score 6, organ confined disease. Biopsy Gleason score (6 vs. 3þ4 vs. 4þ3), PSA density, percentage of positive cores, clinical stage, and PSA were included in logistic regression analyses predicting pathologically favorable PCa and formed the basis for a regression coefficient based nomogram. The area under the curve (AUC) method quantified the predictive accuracy of the model. 200 bootstrap resamples were used for internal validation. Decision curve analyses (DCA) provided an estimate of the net benefit obtained using the proposed model. RESULTS: Mean age was 65.8 years. Overall, 373 (39.3%), 440 (46.3%), and 137 (14.4%) patients had biopsy Gleason score 6, 3þ4, and 4þ3, respectively. Median PSA density and percentage of positive cores were 0.14 ng/ml/ml and 10.9%, respectively. Overall, 244 (25.7%) patients had favorable disease. In multivariable analyses, patients with biopsy Gleason score 6 had higher probability of favorable disease (Odds Ratio [OR]:10.25; P<0.001). Similarly, PSA density (OR:0.01; P<0.001) and percentage of positive cores (OR:0.10; P<0.001) were associated with higher probability of favorable disease at final pathology. The coefficient based nomogram achieved an AUC of 83.8%. Finally, the DCA showed that the proposed model is able to improve clinical risk prediction for patients with a probability of favorable disease between 5 and 80%. CONCLUSIONS: A quarter of contemporary patients with intermediate risk PCa do harbor pathologically favorable disease at RP.
e599
These patients might be considered for alternative treatment modalities, such as active surveillance. We developed a nomogram for the identification of these patients. This model showed excellent predictive performances. Source of Funding: none
MP48-14 TRANSRECTRAL ULTRASOUND GUIDED BIOPSY VERSUS TRANSPERINEAL TEMPLATE PROSTATE BIOPSIES IN DIAGNOSIS OF PROSTATE CANCER IN MEN WITH PREVIOUS NEGATIVE TRANSRECTRAL ULTRASOUND GUIDED BIOPSY Shady Nafie*, John Dormer, Masood Khan, Leicester, United Kingdom INTRODUCTION AND OBJECTIVES: Transperineal template prostate biopsy (TPTPB) has been shown to have a significantly higher cancer detection rate compared to transrectal ultrasound guided (TRUS) biopsy (60% vs. 32%) in biopsy naïve patients with elevated PSA < 20 ng/mL. We performed a prospective study to determine whether TPTPB would still be superior to TRUS biopsy in men with persistently elevated PSA after one previous set of negative TRUS biopsies. METHODS: 42 patients with a background of one previous negative set TRUS biopsy, persistently elevated PSA (but <20 ng/mL) and benign feeling DRE underwent simultaneous standard 12-core TRUS biopsy and 36-core TPTPB under general anaesthetic. We determined the prostate cancer detection rate between the two diagnostic modalities. RESULTS: Mean age is 65 years (range: 50-75), mean prostate volume is 59 cc (range: 21-152), mean PSA is 8.3 ng/L (range: 4.4-19), mean time difference between the study and the previous TRUS biopsy is 33 months (range: 1-150) with mean PSA velocity of 0.7 ng/mL/year (range: 0-8). Out of the 42 patients, 22 (52%) had benign pathology. Of the 20 patients (48%) diagnosed with prostate cancer, 4 (10%) had positive results in both TRUS biopsy and TPTPB, 1 (2%) had positive result in TRUS biopsy with negative TPTPB, while 15 (36%) had negative TRUS biopsy with positive TPTPB. Hence, TRUS biopsy detected cancer in 5/42 (12%) patients versus (19/42) 45% detected by TPTPB (p<0.01). 13/19 (68%) of cancers detected by TPTPB had Gleason score 7. A total of 82/141 (58%) of positive cores was found in the anterior zone. One patient (2%) experienced urosepsis, 2 (5%) temporary urinary retention, 14 (34%) mild haematuria and 13 (32%) haematospermia. CONCLUSIONS: TPTPB still shows a significantly higher prostate cancer detection rate compared to TRUS biopsy (12% vs. 45%, p<0.01) in men with a previous set of negative TRUS biopsy, persistently elevated PSA (but <20 ng/mL) and benign feeling prostate on DRE. Source of Funding: None
MP48-15 EVALUATING THE CLINICAL UTILITY OF TRANSPERINEAL TEMPLATE PROSTATE MAPPING BIOPSY Yaalini Shanmugabavan*, Alex Freeman, Charles Jameson, Massimo Valerio, Mark Emberton, Hashim Uddin Ahmed, London, United Kingdom INTRODUCTION AND OBJECTIVES: Template biopsies are increasingly used to risk stratify prostate cancer. Our aim was to evaluate the impact on clinical decision-making when using transperineal template prostate mapping (TPM) biopsy following a prior standard trans-rectal ultrasound biopsy. METHODS: Our TPM registry database of 699 men had 631 men diagnostic standard TRUS biopsy. The management recommendation after each biopsy result was ascertained from medical records that were recorded prospectively prior to TPM.
THE JOURNAL OF UROLOGYâ
e600
Vol. 193, No. 4S, Supplement, Sunday, May 17, 2015
RESULTS: Median age, mean PSA (pre-TPM) and mean PSA (post-TPM) was 63 years (range 40-84), 7.5ng/ml and 8.7ng/ml, respectively. 349/631 (55.3%) transitioned to higher risk cancer, 71/631 (11%) transitioned to lower risk and 211/631 (34%) had no change in risk category following TPM. After TPM, 138/262 (53%) had a change in recommendation from active surveillance to active treatment. 83/309 (27%) had a change in the type of active treatment they were offered and 218/571 (38%) had no change in treatment recommendation made. 31 men, who were offered active treatment or surveillance, were discharged after their TPM due to a ‘no cancer’ diagnosis. CONCLUSIONS: TPM biopsies, when compared to TRUS biopsies, carry significant clinical utility by directly impacting on management recommendations made to men with prostate cancer. We found a high rate of transitioning men from surveillance to active treatment recommendations although a significant number were also provided reassurance in following a surveillance approach rather than a radical therapeutic approach. Source of Funding: None
MP48-16 CLINICAL UTILITY OF TRANSPERINEAL TEMPLATE GUIDED MAPPING BIOPSY OF PROSTATE AFTER NEGATIVE MAGNETIC RESONANCE IMAGING GUIDED TRANSRECTAL BIOPSY Arjun Sivaraman*, Rafael Sanchez Salas, Eric Barret, Marc Galiano, Francois Rozet, Dominique Prapotnich, Nathalia Cathala, Annick Mombet, Facundo Uriburu Pizarro, Arie Carneiro, Steeve Doizi, Xavier Cathelineau, Paris, France INTRODUCTION AND OBJECTIVES: We evaluated the clinical efficacy of Template guided Transperineal mapping biopsy (TTMB) of prostate in patients with elevated Prostate Specific Antigen (PSA) and prior negative Magnetic Resonance Imaging (MRI) guided biopsy METHODS: We retrospectively reviewed 293 TTMB performed in our institution from April 2013 to August 2014 and identified 75 patients with TTMB done for prior negative TRUS biopsy performed with cognitive MRI guidance.(Table 1) The definitions used for clinically significant caner were Gotto (maximum cancer core length [MCL] 2 or greater mm and/or Gleason grade 3 þ 4 or greater), Harnden (MCL 3 mm or greater and/or Gleason grade 3 þ 4 or greater), University College London (UCL) 2 (MCL 4 mm or greater and/or Gleason grade 3 þ 4 or greater) and UCL 1 (MCL 6 mm or greater and/or Gleason grade 3 þ 4 or greater). Cancers with more than 80% of the positive cores above the level of urethra were termed as Anterior tumors (AT). The results of TTMB were analyzed for cancer detection and correlation with MRI and prostatectomy specimens and complications RESULTS: TTMB detected cancer in 36% (27/75) patients and 66.6% (18/27) of the cancers were AT. Table 2 shows TTMB performance. Significantly higher cancer detection noted in patients with Atypical Small Acinar Proliferation (ASAP) / Prostatic Intraepithelial Neoplasia (PIN) in prior TRUS biopsy(61.5% vs 30.6%, p < 0.05). The clinical and the radiological parameters were similar between the patients with anterior and posterior tumors and also between clinically significant and insignificant cancers. Clavien-Dindo grade 1 and 2 complication was noted in 38.7% (29/75) and 4% (3/75) respectively. Laterality of cancer detected in TTMB correlated with MRI in 74.1% (20/27) patients and in 93.3% (14/15) of radical prostatectomy specimens. Gleason upgrade in RP specimen was noted in 20% (3/15) CONCLUSIONS: TTMB showed good clinical performance in identifying clinically significant cancers in patients with prior negative MRI guided TRUS biopsy and most the cancers were AT
Source of Funding: None
MP48-17 ANTERIOR PROSTATE CANCER: CLINICOPATHOLOGIC CHARACTERIZATION WITH BIOPSY CORRELATION Martin Magers*, Tianyu Zhan, Aaron Udager, Brent Hollenbeck, John Wei, David Miller, Jeffrey Montgomery, Javed Siddiqui, Felix Feng, Daniel Hamstra, Alon Weizer, Todd Morgan, Arul Chinnaiyan, Ganesh Palapattu, Hui Jiang, Rohit Mehra, Ann Arbor, MI INTRODUCTION AND OBJECTIVES: Anterior prostate cancer (APC) is an incompletely understood entity which may be difficult to sample via transrectal biopsy. Seemingly favorable biopsy results may belie the potential aggressiveness of these tumors. Here, we attempt to characterize APC by reviewing our experience at the University of Michigan Health System and correlate our findings with previous biopsy data from these patients. METHODS: All radical prostatectomy (RP) cases with whole mount sections from 1/2012 to 5/2014 were assessed for APC [bulk of index tumor (largest size) anterior to the midpoint of the urethra].
Vol. 193, No. 4S, Supplement, Sunday, May 17, 2015
RESULTS: PCa detection rate was 33.1% (58) and HG-PCa rate 43.1% (25). LS-mMRI was detected in 61 patients (34.9%), ISmMRI in 67 (38.3%) and HS-mMRI in 47 (26.9%). PCa was detected in 6 patients with LS-mMRI (9.8%), 17 with IS-mMRI (25.4%), and 35 with HS-mMRI (74.5%), p<0.001. HG-PCa was detected in 1 patient with LS-mMRI (16.7%), in 4 with IS-mMRI (23.5%), and 14 with HSMRI (40%), p<0.001. Multivariate analysis demonstrated that mMRI was the only independent predictor of PCa, OR: 4.247 (95%CI: 2.182-8.265), however it failed to predict HG-PCa. Establishing the criteria of not rebiopsy patients with LS-mMRI, sensitivity of mMRI was 89.7% (52/58), specificity 47% (55/117), positive predictive value 45.6% (52/114), negative predictive value 90.2% (55/61), rate of avoided biopsies 34.9% (61/175) and rate of non detected PCa 9.8%. The patient with LS-mMRI and HG-PCa (Gleason 4þ4) was subjected to radical prostatectomy and the specimen Gleason score was 3þ4. CONCLUSIONS: mMRI provides useful information to increase the efficiency of standard 12-core TRUS-guided biopsy. Selecting for rPB only those patients with IS or HS-mMRI, more than 30% of rPBs could be avoided with less than 10% probability to lose PCa diagnosis. Source of Funding: none
MP48-13 IDENTIFICATION OF PATHOLOGICALLY FAVORABLE DISEASE IN INTERMEDIATE RISK PROSTATE CANCER PATIENTS: IMPLICATIONS FOR SELECTION OF ACTIVE SURVEILLANCE CANDIDATES Giorgio Gandaglia*, Nazareno Suardi, Marco Bianchi, Nicola Fossati, , Giuseppe Zanni, Milan, Italy; Firas Abdollah, Detroit, MI; Federico Deho Umberto Capitanio, Emanuele Zaffuto, Milan, Italy; Shahrokh F. Shariat, Vienna, Austria; Pierre Karakiewicz, Montreal, Canada; Francesco Montorsi, Alberto Briganti, Milan, Italy INTRODUCTION AND OBJECTIVES: Radical prostatectomy (RP) is associated with excellent outcomes in patients with intermediate-risk Prostate Cancer (PCa). However, this group represents a heterogeneous category. We aimed at identifying predictors and developing a novel model for the identification of pathologically favorable PCa among patients with intermediate-risk disease. METHODS: Overall, 950 patients with intermediate-risk PCa according to D’Amico criteria treated with RP lymph node dissection at a single center between 2006 and 2014 were identified. Pathologically favorable PCa was defined as the presence of pathologic Gleason score 6, organ confined disease. Biopsy Gleason score (6 vs. 3þ4 vs. 4þ3), PSA density, percentage of positive cores, clinical stage, and PSA were included in logistic regression analyses predicting pathologically favorable PCa and formed the basis for a regression coefficient based nomogram. The area under the curve (AUC) method quantified the predictive accuracy of the model. 200 bootstrap resamples were used for internal validation. Decision curve analyses (DCA) provided an estimate of the net benefit obtained using the proposed model. RESULTS: Mean age was 65.8 years. Overall, 373 (39.3%), 440 (46.3%), and 137 (14.4%) patients had biopsy Gleason score 6, 3þ4, and 4þ3, respectively. Median PSA density and percentage of positive cores were 0.14 ng/ml/ml and 10.9%, respectively. Overall, 244 (25.7%) patients had favorable disease. In multivariable analyses, patients with biopsy Gleason score 6 had higher probability of favorable disease (Odds Ratio [OR]:10.25; P<0.001). Similarly, PSA density (OR:0.01; P<0.001) and percentage of positive cores (OR:0.10; P<0.001) were associated with higher probability of favorable disease at final pathology. The coefficient based nomogram achieved an AUC of 83.8%. Finally, the DCA showed that the proposed model is able to improve clinical risk prediction for patients with a probability of favorable disease between 5 and 80%. CONCLUSIONS: A quarter of contemporary patients with intermediate risk PCa do harbor pathologically favorable disease at RP.
e599
These patients might be considered for alternative treatment modalities, such as active surveillance. We developed a nomogram for the identification of these patients. This model showed excellent predictive performances. Source of Funding: none
MP48-14 TRANSRECTRAL ULTRASOUND GUIDED BIOPSY VERSUS TRANSPERINEAL TEMPLATE PROSTATE BIOPSIES IN DIAGNOSIS OF PROSTATE CANCER IN MEN WITH PREVIOUS NEGATIVE TRANSRECTRAL ULTRASOUND GUIDED BIOPSY Shady Nafie*, John Dormer, Masood Khan, Leicester, United Kingdom INTRODUCTION AND OBJECTIVES: Transperineal template prostate biopsy (TPTPB) has been shown to have a significantly higher cancer detection rate compared to transrectal ultrasound guided (TRUS) biopsy (60% vs. 32%) in biopsy naïve patients with elevated PSA < 20 ng/mL. We performed a prospective study to determine whether TPTPB would still be superior to TRUS biopsy in men with persistently elevated PSA after one previous set of negative TRUS biopsies. METHODS: 42 patients with a background of one previous negative set TRUS biopsy, persistently elevated PSA (but <20 ng/mL) and benign feeling DRE underwent simultaneous standard 12-core TRUS biopsy and 36-core TPTPB under general anaesthetic. We determined the prostate cancer detection rate between the two diagnostic modalities. RESULTS: Mean age is 65 years (range: 50-75), mean prostate volume is 59 cc (range: 21-152), mean PSA is 8.3 ng/L (range: 4.4-19), mean time difference between the study and the previous TRUS biopsy is 33 months (range: 1-150) with mean PSA velocity of 0.7 ng/mL/year (range: 0-8). Out of the 42 patients, 22 (52%) had benign pathology. Of the 20 patients (48%) diagnosed with prostate cancer, 4 (10%) had positive results in both TRUS biopsy and TPTPB, 1 (2%) had positive result in TRUS biopsy with negative TPTPB, while 15 (36%) had negative TRUS biopsy with positive TPTPB. Hence, TRUS biopsy detected cancer in 5/42 (12%) patients versus (19/42) 45% detected by TPTPB (p<0.01). 13/19 (68%) of cancers detected by TPTPB had Gleason score 7. A total of 82/141 (58%) of positive cores was found in the anterior zone. One patient (2%) experienced urosepsis, 2 (5%) temporary urinary retention, 14 (34%) mild haematuria and 13 (32%) haematospermia. CONCLUSIONS: TPTPB still shows a significantly higher prostate cancer detection rate compared to TRUS biopsy (12% vs. 45%, p<0.01) in men with a previous set of negative TRUS biopsy, persistently elevated PSA (but <20 ng/mL) and benign feeling prostate on DRE. Source of Funding: None
MP48-15 EVALUATING THE CLINICAL UTILITY OF TRANSPERINEAL TEMPLATE PROSTATE MAPPING BIOPSY Yaalini Shanmugabavan*, Alex Freeman, Charles Jameson, Massimo Valerio, Mark Emberton, Hashim Uddin Ahmed, London, United Kingdom INTRODUCTION AND OBJECTIVES: Template biopsies are increasingly used to risk stratify prostate cancer. Our aim was to evaluate the impact on clinical decision-making when using transperineal template prostate mapping (TPM) biopsy following a prior standard trans-rectal ultrasound biopsy. METHODS: Our TPM registry database of 699 men had 631 men diagnostic standard TRUS biopsy. The management recommendation after each biopsy result was ascertained from medical records that were recorded prospectively prior to TPM.
THE JOURNAL OF UROLOGYâ
e600
Vol. 193, No. 4S, Supplement, Sunday, May 17, 2015
RESULTS: Median age, mean PSA (pre-TPM) and mean PSA (post-TPM) was 63 years (range 40-84), 7.5ng/ml and 8.7ng/ml, respectively. 349/631 (55.3%) transitioned to higher risk cancer, 71/631 (11%) transitioned to lower risk and 211/631 (34%) had no change in risk category following TPM. After TPM, 138/262 (53%) had a change in recommendation from active surveillance to active treatment. 83/309 (27%) had a change in the type of active treatment they were offered and 218/571 (38%) had no change in treatment recommendation made. 31 men, who were offered active treatment or surveillance, were discharged after their TPM due to a ‘no cancer’ diagnosis. CONCLUSIONS: TPM biopsies, when compared to TRUS biopsies, carry significant clinical utility by directly impacting on management recommendations made to men with prostate cancer. We found a high rate of transitioning men from surveillance to active treatment recommendations although a significant number were also provided reassurance in following a surveillance approach rather than a radical therapeutic approach. Source of Funding: None
MP48-16 CLINICAL UTILITY OF TRANSPERINEAL TEMPLATE GUIDED MAPPING BIOPSY OF PROSTATE AFTER NEGATIVE MAGNETIC RESONANCE IMAGING GUIDED TRANSRECTAL BIOPSY Arjun Sivaraman*, Rafael Sanchez Salas, Eric Barret, Marc Galiano, Francois Rozet, Dominique Prapotnich, Nathalia Cathala, Annick Mombet, Facundo Uriburu Pizarro, Arie Carneiro, Steeve Doizi, Xavier Cathelineau, Paris, France INTRODUCTION AND OBJECTIVES: We evaluated the clinical efficacy of Template guided Transperineal mapping biopsy (TTMB) of prostate in patients with elevated Prostate Specific Antigen (PSA) and prior negative Magnetic Resonance Imaging (MRI) guided biopsy METHODS: We retrospectively reviewed 293 TTMB performed in our institution from April 2013 to August 2014 and identified 75 patients with TTMB done for prior negative TRUS biopsy performed with cognitive MRI guidance.(Table 1) The definitions used for clinically significant caner were Gotto (maximum cancer core length [MCL] 2 or greater mm and/or Gleason grade 3 þ 4 or greater), Harnden (MCL 3 mm or greater and/or Gleason grade 3 þ 4 or greater), University College London (UCL) 2 (MCL 4 mm or greater and/or Gleason grade 3 þ 4 or greater) and UCL 1 (MCL 6 mm or greater and/or Gleason grade 3 þ 4 or greater). Cancers with more than 80% of the positive cores above the level of urethra were termed as Anterior tumors (AT). The results of TTMB were analyzed for cancer detection and correlation with MRI and prostatectomy specimens and complications RESULTS: TTMB detected cancer in 36% (27/75) patients and 66.6% (18/27) of the cancers were AT. Table 2 shows TTMB performance. Significantly higher cancer detection noted in patients with Atypical Small Acinar Proliferation (ASAP) / Prostatic Intraepithelial Neoplasia (PIN) in prior TRUS biopsy(61.5% vs 30.6%, p < 0.05). The clinical and the radiological parameters were similar between the patients with anterior and posterior tumors and also between clinically significant and insignificant cancers. Clavien-Dindo grade 1 and 2 complication was noted in 38.7% (29/75) and 4% (3/75) respectively. Laterality of cancer detected in TTMB correlated with MRI in 74.1% (20/27) patients and in 93.3% (14/15) of radical prostatectomy specimens. Gleason upgrade in RP specimen was noted in 20% (3/15) CONCLUSIONS: TTMB showed good clinical performance in identifying clinically significant cancers in patients with prior negative MRI guided TRUS biopsy and most the cancers were AT
Source of Funding: None
MP48-17 ANTERIOR PROSTATE CANCER: CLINICOPATHOLOGIC CHARACTERIZATION WITH BIOPSY CORRELATION Martin Magers*, Tianyu Zhan, Aaron Udager, Brent Hollenbeck, John Wei, David Miller, Jeffrey Montgomery, Javed Siddiqui, Felix Feng, Daniel Hamstra, Alon Weizer, Todd Morgan, Arul Chinnaiyan, Ganesh Palapattu, Hui Jiang, Rohit Mehra, Ann Arbor, MI INTRODUCTION AND OBJECTIVES: Anterior prostate cancer (APC) is an incompletely understood entity which may be difficult to sample via transrectal biopsy. Seemingly favorable biopsy results may belie the potential aggressiveness of these tumors. Here, we attempt to characterize APC by reviewing our experience at the University of Michigan Health System and correlate our findings with previous biopsy data from these patients. METHODS: All radical prostatectomy (RP) cases with whole mount sections from 1/2012 to 5/2014 were assessed for APC [bulk of index tumor (largest size) anterior to the midpoint of the urethra].