Impact of pathologic features on local recurrence in penile squamous cell carcinoma after penectomy

BACKGROUND

Penile squamous cell carcinoma (PSCC) is a rare malignancy that may be cured in cases of local disease by resection of the primary tumor. Risk factors and patterns of local recurrence (LR) have not been well described in cases requiring partial or radical penectomy. In this study, we evaluated risk factors for LR and the impact of frozen and final margin assessment.

MATERIALS AND METHODS

We evaluated 119 patients with PSCC who had undergone partial or radical penectomy from 2007 to 2023. Data regarding clinical and pathologic features were collected by retrospective chart review. The primary outcome of interest was LR. Determinants of LR were analyzed by Student's t, Fisher's exact, chi-square and logistic regression analysis. Predictive statistics of frozen margin status on final margin were assessed and LR rates for subsets of frozen and final margin interaction were defined. Finally, all cases of positive margins and LR were described to highlight patterns of LR and the importance of margin status in these cases.

RESULTS

There were 8 (6.7%) cases of local recurrence. There were no significant predictors of LR, although a trend toward increased LR risk was observed among those with a positive final margin. Positive final margins were found in 15 (13%) cases. Frozen margin analysis was utilized in 79 cases, of which 10 (13%) were positive. The sensitivity, specificity, positive predictive value, and negative predictive value of frozen margin status for final margins were 44%, 92%, 40%, and 93%, respectively. There were no LR among cases in which frozen margin was not sent. Analysis of all cases with positive margin and/or LR identified three subsets of patients: CIS or focally positive margin resulting in either no LR or LR managed with minimal local intervention, bulky disease in which survival is determined by response to subsequent therapy rather than local recurrence, and clinically significant local recurrence requiring continued surveillance and intervention despite negative margins.

CONCLUSIONS

LR is rare, even in cases of larger, proximal tumors requiring partial or radical penectomy. In this study, no statistically significant risk factors for local recurrence were identified; however, analysis of frozen and final margins provided insight into the importance of margin status and patterns of local recurrence. When feasible, visibly intra-operative negative margins are an excellent predictor of low risk for LR, and, in cases of CIS or focally positive margins, further resection to achieve negative margins is unlikely to reduce the risk of clinically significant LR. Additionally, in cases of bulky disease, the goals of resection should be focused toward palliation and next line therapy.

Optimal Prostate Cancer Diagnostic Pathways for Men With Prostatomegaly in the MRI Era

OBJECTIVE

To evaluate utilities of multiparametric MRI and targeted biopsy to detect clinically significant prostate cancer in men with prostatomegaly.

MATERIALS AND METHODS

We conducted a retrospective review of multiparametric MRI obtained for elevated PSA between 2017 and 2020. We selected patients with prostates ≥80 g who had undergone biopsy. Clinically significant prostate cancer was defined as grade group ≥2. Predictive and logistic regression analyses quantified impacts of diagnostic components.

RESULTS

A total of 338 patients met inclusion criteria: 89 (26.3%) had clinically significant prostate cancer. On MRI, positive predictive value for clinically significant prostate cancer was 26.5% for PIRADS 4% and 73.5% for PIRADS 5; negative predictive value for MRI without suspicious lesions was 98.8%. Applying PSA density to MRI yielded a negative predictive value of 78.9% for PIRADS 4 lesions at PSA density <0.05 and a positive predictive value of 90.5% for PIRADS 5 lesions at PSA density ≥0.15. Targeted (versus standard) biopsy reduced likelihood of missing clinically significant prostate cancer by >50% (12.2% vs 28.3%). MRI in-bore biopsies trended towards better accuracy versus MRI-transrectal ultrasound fusion biopsies (75% versus 52%). On logistic regression analyses, MRI improved predictive accuracy (area under the curve 0.91), and PIRADS score demonstrated the strongest association with clinically significant prostate cancer (odds ratio 6.42, P < .001).

CONCLUSION

For large prostates, MRI is less predictive of clinically significant prostate cancer but effectively rules out malignancy. PSA density better informs biopsy decisions for PIRADS 4 and 5 lesions. There may be a pronounced role for targeted biopsy, specifically in-bore, in prostatomegaly.

Outcomes of patients undergoing concurrent radical cystectomy and nephroureterectomy: A single-institution series

INTRODUCTION

Radical cystectomy (RC) and radical nephroureterectomy (RNU) are commonly performed in urological oncology. Concurrent disease in the upper tract and bladder is rare, so performing both procedures in the same setting is uncommon. Here, we report the perioperative and oncological outcomes of a single-institution series of concurrent RC+RNU.

METHODS

We retrospectively reviewed the charts of patients who underwent concurrent RC+RNU for bladder and/or upper tract urothelial carcinoma between 2006 and 2020. Patient demographic and clinical factors, perioperative parameters, and oncological outcomes were obtained.

RESULTS

Twenty-seven patients underwent RC+RNU during the study period; 22 (81%) were male. Median (interquartile range) patient age was 71 (67-75) years. All had a diagnosis of bladder cancer. Concurrent upper tract urothelial carcinoma (UTUC) was the indication for RNU in 12 cases (44%) and non-functional renal unit in the remainder. Two patients (7%) experienced early postoperative mortality. Eight patients (30%) experienced major complications (Clavien-Dindo >3). Complications did not vary significantly between those rendered anephric (5/16, 31%) and those who were not (3/11, 27%) (p=0.82, Chi-squared test). Median (95% confidence interval) and five-year overall survival were 47 (41-52) months and 42%, respectively. Six of 22 male patients (27%) experienced a urethral recurrence and three of 14 patients (21%) with non-functional kidneys had occult UTUC discovered on final pathology.

CONCLUSIONS

Combined RC+RNU carries an elevated perioperative risk, primarily in highly comorbid patients. Striking rates of occult UTUC in non-functional kidneys and of urethral recurrence after cystectomy were noted. RC+RNU is an appropriate option in select patients.

Risk of adverse pathology at prostatectomy in the era of MRI and targeted biopsies; rethinking active surveillance for intermediate risk prostate cancer patients

PURPOSE

Men with intermediate risk (IR) prostate cancer (CaP) are often excluded from active surveillance (AS) due to higher rates of adverse pathology (AP). We determined our rate of AP in men who underwent multiparametric MRI (MpMRI) with combined biopsy (CB) consisting of targeted biopsy (TB) and systematic biopsy (SB) prior to radical prostatectomy (RP).

METHODS

A retrospective review was conducted of men with Gleason Grade Group (GG) 2 disease who underwent RP after SB alone or after preoperative MRI with CB. AP was defined as either pathologic stage T3a (AP ≥ T3a) or pathologic stage T3b (AP ≥ T3b) and/or GG upgrading. Rates of AP were determined for both groups and those who fit the National Comprehensive Cancer Network (NCCN) definition of favorable IR (FIR) or the low volume IR (LVIR) criteria. Multivariable logistic regression was used to determine predictive factors.

RESULTS

The overall rate of AP ≥ T3b was 21.2% in the SB group vs. 8.6% in the MRI with CB group, P = 0.006. This rate was lowered to 6.8% and 5.6% when men met the definition of NCCN FIR or LVIR, respectively. Suspicion for extraprostatic extension (EPE) (OR 7.65, 95% CI 1.77-33.09, P = 0.006) and positive cores of GG 2 on SB (OR 1.43, 95% CI 1.05-1.96, P = 0.023) were significant for predicting AP ≥ T3b.

CONCLUSIONS

Rates of AP at RP after MRI with CB are lower than studies prior to the adoption of this technology, suggesting that more men with IR disease may be considered for AS. However, increasing cores positive on SB and MRI findings suggestive of EPE remain unsafe.

Does size matter? Lesion size as an indicator of number of cores needed to detect clinically significant prostate cancer

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Background: MRI/US fusion guided prostate biopsy (FBx) has been shown to detect clinically significant prostate cancer (csCaP) at higher rates and with fewer cores than standard prostate biopsy. Size plays an important role in assigning a suspicion level (PI-RADS) to lesions identified on MRI. However, tumor characteristics may pose challenges to accurately characterizing the lesion despite the size. This study sought to determine if there are size cutoffs at which a lesion may be accurately characterized as clinically significant cancer with a single biopsy core. Methods: A retrospective analysis of a prospectively maintained database of all patients undergoing FBx at an academic referral center between May 2014 and January 2018 was conducted. At least two FBx cores were taken from each lesion identified on mpMRI. GEE-based univariate logistic regression model with exchangeable correlation was used determine if size was a significant predictor of positive and negative agreement. Predictability of size as a significant continuous predictor was quantified by AUC. Size thresholds at which multiple cores per lesion are needed to avoid missing > 2% of csCaP were calculated, allowing for a 25% discordance rate. Results: An analysis of a total of 1141 FBx of 2200 lesions was performed during the study time interval. Size was a significant predictor of both positive (OR = 2.43, 1.83-3.23, p < 0.01) and negative (OR = 0.58, 0.44-0.76, p < 0.01) agreement of csCaP. AUC% for positive and negative agreement was 65.8 and 57.6, respectively. Size thresholds of 0.65 and 1.70 cm limited CS cancers missed by skipping a second targeted biopsy core to 2% while allowing for a 25% discordance. Conclusions: These data indicate that clinically significant prostate cancer in lesions less than 0.65 cm and greater than 1.70 cm may be characterized with a single targeted biopsy core, sparing 33.5% of lesions (21% patients) a double core targeted biopsy.

Use of multiparametric magnetic resonance imaging and fusion-guided biopsies to properly select and follow African-American men on active surveillance

OBJECTIVES

To determine the rate of Gleason Grade Group (GGG) upgrading in African-American (AA) men with a prior diagnosis of low-grade prostate cancer (GGG 1 or GGG 2) on 12-core systematic biopsy (SB) after multiparametric magnetic resonance imaging (mpMRI) and fusion biopsy (FB); and whether AA men who continued active surveillance (AS) after mpMRI and FB fared differently than a predominantly Caucasian (non-AA) population.

PATIENTS AND METHODS

A database of men who had undergone mpMRI and FB was queried to determine rates of upgrading by FB amongst men deemed to be AS candidates based on SB prior to referral. After FB, Kaplan-Meier curves were generated for AA men and non-AA men who then elected AS. The time to GGG upgrading and time continuing AS were compared using the log-rank test.

RESULTS

AA men referred with GGG 1 disease on previous SB were upgraded to GGG ≥3 by FB more often than non-AA men, 22.2% vs 12.7% (P = 0.01). A total of 32 AA men and 258 non-AA men then continued AS, with a median (interquartile range) follow-up of 39.19 (24.24-56.41) months. The median time to progression was 59.7 and 60.5 months, respectively (P = 0.26). The median time continuing AS was 61.9 months and not reached, respectively (P = 0.80).

CONCLUSIONS

AA men were more likely to be upgraded from GGG 1 on SB to GGG ≥3 on initial FB; however, AA and non-AA men on AS subsequently progressed at similar rates following mpMRI and FB. A greater tendency for SB to underestimate tumour grade in AA men may explain prior studies that have shown AA men to be at higher risk of progression during AS.

When to Biopsy the Seminal Vesicles: A Validated Multiparametric Magnetic Resonance Imaging and Target Driven Model to Detect Seminal Vesicle Invasion of Prostate Cancer

PURPOSE

Current imaging and biopsy practices offer limited insight into preoperative detection of seminal vesicle invasion despite the implications for treatment decisions and patient prognoses. We identified magnetic resonance imaging features to assess the risk of seminal vesicle invasion and inform the inclusion of seminal vesicle sampling during biopsy.

MATERIALS AND METHODS

Patients underwent multiparametric magnetic resonance imaging and fusion targeted biopsy with or without seminal vesicle biopsy. Magnetic resonance imaging suspicion of seminal vesicle invasion, multiparametric magnetic resonance imaging of prostate base lesions of moderate or greater suspicion, extraprostatic extension, anatomical zone and biopsy data were used to generate multivariable logistic regression models. One model without and one with biopsy data were externally validated in a multi-institutional cohort. Decision curve analyses were done to determine net benefit of the 2 models.

RESULTS

The training and validation cohorts comprised 564 and 250 patients, respectively. In the training cohort 55 patients (9.8%) had pathologically confirmed seminal vesicle invasion. In the prebiopsy model magnetic resonance imaging suspicion of seminal vesicle invasion (OR 9.5, 95% CI 4.0-22.4, p <0.001), multiparametric magnetic resonance imaging base lesions of moderate or greater suspicion with extraprostatic extension (OR 13.6, 95% CI 4.0-46.5, p <0.001), and a transition and/or central zone location (OR 11.6, 95% CI 3.5-38.3, p <0.001) showed strong correlations. In the post-biopsy model the risk of pathologically confirmed seminal vesicle invasion increased with the base Gleason Group (Gleason Group 5 OR 85.3, 95% CI 11.8-619.1, p <0.001). In the validation cohort the AUC of the prebiopsy and post-biopsy models was 0.84 and 0.93, respectively (p = 0.030).

CONCLUSIONS

Magnetic resonance imaging evidence of seminal vesicle invasion or extraprostatic extension at the prostate base transition and/or central zone and high grade prostate cancer from the prostate base are significant features associated with an increased risk of pathologically confirmed seminal vesicle invasion. Our models successfully incorporated these features to predict seminal vesicle invasion and inform when to biopsy the seminal vesicles.

mpMRI preoperative staging in men treated with antiandrogen and androgen deprivation therapy before robotic prostatectomy

INTRODUCTION

Using multiparametric magnetic resonance imaging (mpMRI), we sought to preoperatively characterize prostate cancer (PCa) in the setting of antiandrogen plus androgen deprivation therapy (AA-ADT) prior to robotic-assisted radical prostatectomy (RARP). We present our preliminary findings regarding mpMRI depiction of changes of disease staging features and lesion appearance in treated prostate.

METHODS

Prior to RARP, men received 6 months of enzalutamide and goserelin. mpMRI consisting of T2 weighted, b = 2,000 diffusion weighted imaging, apparent diffusion coefficient mapping, and dynamic contrast enhancement sequences was acquired before and after neoadjuvant therapy. Custom MRI-based prostate molds were printed to directly compare mpMRI findings to H&E whole-mount pathology as part of a phase II clinical trial (NCT02430480).

RESULTS

Twenty men underwent imaging and RARP after a regimen of AA-ADT. Positive predictive values for post-AA-ADT mpMRI diagnosis of extraprostatic extension, seminal vesicle invasion, organ-confined disease, and biopsy-confirmed PCa lesions were 71%, 80%, 80%, and 85%, respectively. Post-treatment mpMRI correctly staged disease in 15/20 (75%) cases with 17/20 (85%) correctly identified as organ-confined or not. Of those incorrectly staged, 2 were falsely positive for higher stage features and 1 was falsely negative. Post-AA-ADT T2 weighted sequences best depicted presence of PCa lesions as compared to diffusion weighted imaging and dynamic contrast enhancement sequences.

CONCLUSION

mpMRI proved reliable in detecting lesion changes after antiandrogen therapy corresponding to PCa pathology. Therefore, mpMRI of treated prostates may be helpful for assessing men for surgical planning and staging.

MRI-TRUS fusion-guided biopsy in obese patients: Does it reduce risk of prostate cancer upgrade on final pathology compared to systematic 12-core biopsy?

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Background: Epidemiologic data suggests a link between obesity and increased risk of aggressive prostate cancer (PCa). Therefore, the accurate detection of prostate cancer is paramount in obese men. We sought to characterize the PCa lesions seen on multiparametric magnetic resonance imaging (mpMRI) in both obese (OB) and non-obese (nOB) patients. In addition, we examined whether obesity affects the accuracy of fusion biopsy (FBx) versus systematic biopsy (SBx). Methods: Data from patients who underwent FBx, SBx, or both, and subsequent prostatectomy at a single institution between 2007-2017 were reviewed. Men were stratified into three groups based on body mass index (BMI): normal weight (18.5-24.9), overweight (25.0-29.9), and obese (≥30.0). mpMRIs were analyzed to determine prostate size, lesion size, lesion location, and evidence of ≥T3 disease. FBx and SBx were compared to prostatectomy specimens. These variables were then analyzed between the OB and nOB groups. Results: 487 patients were included: 109 (19%) normal weight, 266 (48%) overweight, and 185 (33%) obese. No statistical differences were noted in age, PSA, or clinical stage. mpMRI showed similar prostate size, index and total lesion diameter, lesion location, and Prostate Imaging Reporting and Data System (PIRADS) score between BMI categories. In OB patients, FBx was better able to predict final Gleason score (GS) than SBx, 60% vs 47%, p = 0.0474, OR 1.67 (1.00-2.80). The rate of upgrading after SBx was higher for OB men versus nOB men, 44% vs 34%, p = 0.034, OR 1.52 (1.01-2.29). However, risk of upgrading returned to that of nOB men with FBx, 20% vs 17%, p = 0.538, OR 1.21 (0.658-2.23). Conclusions: FBx is a more accurate measure of the true GS in OB patients than SBx, and there is a significantly greater risk of underrepresenting PCa on SBx in OB patients. These findings were not associated with differences in prostate sizes and lesion characteristics on mpMRI. This suggests that obesity may cause technical challenges with prostate biopsies that may be overcome by improved visualization and targeting of FBx.

One and done?: Utility of PSA density as a predictor of number of cores needed to detect clinically significant prostate cancer

104

Background: MRI/US fusion guided prostate biopsy (FBx) has been shown to detect clinically significant prostate cancer (csCaP) at higher rates and with fewer cores than standard prostate biopsy. However, the number of targeted cores needed to accurately characterize lesions identified on multiparametric MRI (mpMRI) is unknown. This study sought to determine factors that predict the number of cores needed to accurately characterize lesions during FBx of patients on active surveillance. Methods: A retrospective analysis of a prospectively maintained database of all patients undergoing FBx at an academic referral center between May 2014 and January 2018 was conducted. At least two FBx cores were taken from each lesion identified on mpMRI. Patient and lesion specific factors were analyzed to determine factors that predict the necessity to obtain additional cores to detect csCaP. GEE-based univariate logistic regression model with exchangeable correlation was used to estimate the effects of clinical characteristics including race, BMI, PSA, PSA density (PSAD), lesion location, and PI-RADS score on the proportion of positive and negative agreement. Predictability of a significant continuous predictor was quantified by AUC. The most significant patient-level predictor (PSAD) was further analyzed to determine thresholds at which multiple cores per lesion are needed to avoid missing csCaP. Results: An analysis of a total of 1141 FBx were performed during the study time interval. PSA (OR=1.57, 1.20-2.05, p<0.01) and PSAD (OR=1.43, 1.11-1.85, p<0.01) significantly predicted positive agreement of csCaP. AUC for positive and negative agreement was 57.4 and 61.0 for PSA and 56.4 and 72.3 for PSAD, respectively. Using these thresholds, only 56% lesions would need double core targeted biopsy. In other words, up to 44% of lesions would be accurately characterized with a single biopsy core of the targeted lesion. Conclusions: These data indicate that in patients with a PSAD less than 0.11 ng/ml2 or greater than 0.26 ng/ml2, lesions may be acceptably characterized with a single targeted biopsy core.

MRI targeted biopsy dramatically increases detection of clinically significant prostate cancer while reducing the risk of indolent cancer detection

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Background: MRI fusion prostate biopsy has been shown to improve detection of clinically significant prostate cancer, however the degree of this benefit is poorly characterized in large clinical trials. Methods: 1750 MRI targeted plus sextant biopsies were performed in 1742 male patients from 2007 to 2017. Patient demographics, PSA, prostate volume, primary and secondary Gleason scores, Johns Hopkins Grade Groups, number of MRI targeted lesions, number of cores obtained, and biopsy yield were recorded. Results: The patient population consisted of men averaging 62.9-year-old (36-86) with a mean PSA 9.6ng/mL, and prostate volume of 59.2 ml. A total of 804 cancers were detected on sextant biopsy and 839 were detected on MRI targeted biopsy. Relative to targeted biopsy, sextant biopsy detected only significantly more Gleason 6 disease (14% vs 21.5%, p < 0.0001) than targeted biopsy. Targeted biopsy detected more Gleason 7 (21% vs 16.6%, p = 0.0009) and Gleason 8-10 (13.4% vs 9.4%). Additionally, Gleason 7 sub-stratification demonstrated substantially more Gleason 4+3 detection in targeted group vs sextant biopsy (4% vs 0.5%, p < 0.0001). When stratified by Grade Group targeted biopsy detected 76% more Grade Group 3-5 cancers (p < 0.0001) and 17.7% less Gleason Group 1-2 cancers (p < 0.0001). Only 1.7% of Grade Group 3-5 cancers were detected on sextant biopsy alone, where as 15.7% of Grade Group 3-5 cancers were detected on targeted biopsy alone. Conclusions: MRI targeted biopsy significantly increases the likelihood of detecting clinically significant cancer and decreases the risk of indolent cancer detection. These finding strongly support the use of MRI targeted biopsy when possible.

Evaluation of preoperative prostate magnetic resonance imaging for cancer control and neurovascular tissue preservation during robotic radical prostatectomy

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Background: Prostate multi-parametric magnetic resonance imaging (mpMRI) can precisely depict prostate cancer (PCa) location and adverse pathologic features. Surgeons can utilize this information to maximize sparing of the neurovascular bundles (NVBs) during radical prostatectomy (RP) while avoiding a positive surgical margin (PSM). We detail the technique of using preoperative mpMRI to quantify its effect regarding nerve-sparing and rates of PSMs. Methods: A prospectively maintained database was queried for robotic-assisted RPs (RARPs) with preoperative mpMRI between 2007-2017. Imaging margin risk factors (iMRF) were defined on mpMRI as frank extraprostatic extension (EPE), possible EPE, and capsular irregularity (capsular bulge, lesion-capsule contact, or lesion adjacency to the neurovascular bundles). Surgical adjustments to nerve-sparing technique (full sparing, partial sparing, and wide excision) were made based on these findings. Results: Five hundred thirty-two patients comprising 1041 prostate sides were included for analysis. Overall, PSM rate was found in 80/1041 (7.7%) sides of the prostate. iMRF were seen in 313/1041 (30.1%) prostate sides, for which adjustments were made in 244/313 (78.0%) of these. In the 69/244 (22.0%) cases where full nerve-sparing was performed despite iMRF, PSM rate was 20/69 (29%) compared to 33/244 (13.5%), p = 0.002. MRI-guided surgical adjustments decreased PSM risk by 68% and 15% in pT3 and pT2 cases, respectively. On multivariable analysis, logPSA (odds ratio [OR] 4.06, [95% CI 2.40-12.3], p < 0.001) and iMRF (OR 1.78, [95% CI 1.01-3.16], p = 0.047) were significantly associated with PSM while nerve-sparing adjustment was significantly associated with decreased risk of PSM (OR 0.38 [95% CI 0.22-0.66], p = 0.001). Conclusions: MRI effectively detects risks for PSM and guides surgical adjustments to decrease PSM rates. As prostate MRI is more frequently acquired for PCa screening and biopsy, we show its additional value for RP planning and potentially improved outcomes.

Predicting Gleason Group Progression for Men on Prostate Cancer Active Surveillance: Role of a Negative Confirmatory Magnetic Resonance Imaging-Ultrasound Fusion Biopsy

PURPOSE

Active surveillance has gained acceptance as an alternative to definitive therapy in many men with prostate cancer. Confirmatory biopsies to assess the appropriateness of active surveillance are routinely performed and negative biopsies are regarded as a favorable prognostic indicator. We sought to determine the prognostic implications of negative multiparametric magnetic resonance imaging-transrectal ultrasound guided fusion biopsy consisting of extended sextant, systematic biopsy plus multiparametric magnetic resonance imaging guided targeted biopsy of suspicious lesions on magnetic resonance imaging.

MATERIALS AND METHODS

All patients referred with Gleason Grade Group 1 or 2 prostate cancer based on systematic biopsy performed elsewhere underwent confirmatory fusion biopsy. Patients who continued on active surveillance after a positive or a negative fusion biopsy were followed. The baseline characteristics of the biopsy negative and positive cases were compared. Cox regression analysis was used to determine the prognostic significance of a negative fusion biopsy. Kaplan-Meier survival curves were used to estimate Grade Group progression with time.

RESULTS

Of the 542 patients referred with Grade Group 1 (466) or Grade Group 2 (76) cancer 111 (20.5%) had a negative fusion biopsy. A total of 60 vs 122 patients with a negative vs a positive fusion biopsy were followed on active surveillance with a median time to Grade Group progression of 74.3 and 44.6 months, respectively (p <0.01). Negative fusion biopsy was associated with a reduced risk of Grade Group progression (HR 0.41, 95% CI 0.22-0.77, p <0.01).

CONCLUSIONS

A negative confirmatory fusion biopsy confers a favorable prognosis for Grade Group progression. These results can be used when counseling patients about the risk of progression and for planning future followup and biopsies in patients on active surveillance.

Incidental bladder cancers found on multiparametric MRI of the prostate gland: a single center experience

PURPOSE

In the era of multiparametric magnetic resonance imaging (mpMRI) of the prostate gland, incidental findings are occasionally discovered on imaging. We aimed to report our experience of detecting incidental bladder cancers on mpMRI of the prostate in asymptomatic patients without irritative voiding symptoms or microscopic or gross hematuria.

METHODS

A retrospective review was performed on a prospectively maintained database of all men who underwent prostate mpMRI at our institution from 2012 to 2018. Patients who were found to have incidental bladder lesions were identified and baseline demographics, imaging and histopathologic data were recorded. All patients with incidental bladder lesion detection on mpMRI, not attributable to extension of prostate cancer, underwent cystoscopy in addition to a biopsy and/or transurethral resection of bladder tumor (TURBT) if warranted on cystoscopy.

RESULTS

There were 3147 prostate mpMRIs performed during this period and 25 cases (0.8%) of incidental bladder lesions were detected. These patients did not have any presenting symptoms such as gross or microscopic hematuria to prompt bladder lesion workup. The largest diameter of incidentally discovered bladder lesions ranged from 0.4 cm to 1.7 cm. Of the 25 cases of incidental bladder lesions, five were suspected to be due to prostate cancer invasion into the bladder. Only two of these five patients underwent biopsy, which confirmed prostate adenocarcinoma in both cases. Of the 20 patients without suspected prostate cancer invasion of the bladder, four had no suspicious lesions on cystoscopy to warrant a biopsy. The remaining 16 patients had bladder lesions seen on cystoscopy and underwent a biopsy and/or TURBT. Three of these patients had benign features on pathology (urachal remnant, amyloidosis and inflammation) and the remaining 13 had stage Ta urothelial carcinoma. Seven of these patients had low-grade Ta tumors and six had high-grade Ta tumors. All patients were treated with standard management of TURBT with or without intravesical BCG. There have been no reported cases of recurrence or progression in any of the patients in our cohort at the median follow-up of 26 months (interquartile range,19-40 months).

CONCLUSION

mpMRI of the prostate may yield incidental findings, such as small bladder tumors. Awareness of the possibility of incidental bladder lesions is important as 65% of lesions reported in the bladder, not attributable to extension of prostate cancer, proved to be bladder cancer. This may allow for early intervention for asymptomatic patients with undetected bladder cancer prior to disease progression.

Lymph node imaging of pediatric renal and suprarenal malignancies

Pediatric renal and suprarenal cancers are relatively rare malignancies, but are not without significant consequence to both the patient and caretakers. These tumors are often found incidentally and present as large abdominal masses. Standard of care management involves surgical excision of the mass, but contemporary treatment guidelines advocate for use of neoadjuvant or adjuvant chemotherapy for advanced stage disease, such as those cases with lymph node involvement (LNI). However, LNI detection is based primarily on surgical pathology and performing extended lymph node dissection can add significant morbidity to a surgical case. In this review, we focus on the use and performance of imaging modalities to detect LNI in Wilms’ tumor (WT), neuroblastoma, and pediatric renal cell carcinoma (RCC). We report on how imaging impacts management of these cases and the clinical implications of LNI. A literature search was conducted for studies published on imaging-based detection of LNI in pediatric renal and suprarenal cancers. Further review focused on surgical and medical management of those cases with suspected LNI. Current imaging protocols assisting in diagnosis and staging of pediatric renal and suprarenal cancers are generally limited to abdominal ultrasound and cross-sectional imaging, mainly computed tomography (CT). Recent research has investigated the role of more advance modalities, such as magnetic resonance imaging (MRI) and positron emission tomography (PET), in the management of these malignancies. Special consideration must be made for pediatric patients who are more vulnerable to ionizing radiation and have characteristic imaging features different from adult controls. Management of pediatric renal and suprarenal cancers is influenced by LNI, but the rarity of these conditions has limited the volume of clinical research regarding imaging-based staging. As such, standardized criteria for LNI on imaging are lacking. Nevertheless, advanced imaging modalities are being investigated and potentially represent more accurate and safer options.

Lymph node imaging in testicular cancer

Testicular cancer is a rare malignancy mainly affecting young men. Survival for testicular cancer remains high due to the effectiveness of multimodal treatment options. Accurate imaging is imperative to both treatment and follow-up. Both computed tomography (CT) and magnetic resonance imaging (MRI) suffer from size cut-offs as the only distinguishing characteristic of benign vs. malignant lymph nodes and may miss up to 30% of micro-metastatic disease. While functional [positron emission tomography (PET)] imaging may rule out disease in patients with seminoma who have undergone chemotherapy, there is insufficient evidence to recommend its use in other settings. This review highlights the uses and pitfalls of conventional imaging during staging, active surveillance, and post-treatment phases of both seminomatous and non-seminomatous germ cell tumors (NSGCT).

Comparison of Elastic and Rigid Registration during Magnetic Resonance Imaging/Ultrasound Fusion-Guided Prostate Biopsy: A Multi-Operator Phantom Study

PURPOSE

The relative value of rigid or elastic registration during magnetic resonance imaging/ultrasound fusion guided prostate biopsy has been poorly studied. We compared registration errors (the distance between a region of interest and fiducial markers) between rigid and elastic registration during fusion guided prostate biopsy using a prostate phantom model.

MATERIALS AND METHODS

Four gold fiducial markers visible on magnetic resonance imaging and ultrasound were placed throughout 1 phantom prostate model. The phantom underwent magnetic resonance imaging and the fiducial markers were labeled as regions of interest. An experienced user and a novice user of fusion guided prostate biopsy targeted regions of interest and then the corresponding fiducial markers on ultrasound after rigid and then elastic registration. Registration errors were compared.

RESULTS

A total of 224 registration error measurements were recorded. Overall elastic registration did not provide significantly improved registration error over rigid registration (mean ± SD 4.87 ± 3.50 vs 4.11 ± 2.09 mm, p = 0.05). However, lesions near the edge of the phantom showed increased registration errors when using elastic registration (5.70 ± 3.43 vs 3.23 ± 1.68 mm, p = 0.03). Compared to the novice user the experienced user reported decreased registration error with rigid registration (3.25 ± 1.49 vs 4.98 ± 2.10 mm, p <0.01) and elastic registration (3.94 ± 2.61 vs 6.07 ± 4.16 mm, p <0.01).

CONCLUSIONS

We found no difference in registration errors between rigid and elastic registration overall but rigid registration decreased the registration error of targets near the prostate edge. Additionally, operator experience reduced registration errors regardless of the registration method. Therefore, elastic registration algorithms cannot serve as a replacement for attention to detail during the registration process and anatomical landmarks indicating accurate registration when beginning the procedure and before targeting each region of interest.

Added Value of Multiparametric Magnetic Resonance Imaging to Clinical Nomograms for Predicting Adverse Pathology in Prostate Cancer

PURPOSE

We examined the additional value of preoperative prostate multiparametric magnetic resonance imaging and transrectal ultrasound/multiparametric magnetic resonance imaging fusion guided targeted biopsy when performed in combination with clinical nomograms to predict adverse pathology at radical prostatectomy.

MATERIALS AND METHODS

We identified all patients who underwent 3 Tesla multiparametric magnetic resonance imaging prior to fusion biopsy and radical prostatectomy. The Partin and the MSKCC (Memorial Sloan Kettering Cancer Center) preradical prostatectomy nomograms were applied to estimate the probability of organ confined disease, extraprostatic extension, seminal vesicle invasion and lymph node involvement using transrectal ultrasound guided systematic biopsy and transrectal ultrasound/multiparametric magnetic resonance imaging fusion guided targeted biopsy Gleason scores. With radical prostatectomy pathology as the gold standard we developed multivariable logistic regression models based on these nomograms before and after adding multiparametric magnetic resonance imaging to assess any additional predictive ability.

RESULTS

A total of 532 patients were included in study. When multiparametric magnetic resonance imaging findings were added to the systematic biopsy based MSKCC nomogram, the AUC increased by 0.10 for organ confined disease (p <0.001), 0.10 for extraprostatic extension (p = 0.003), 0.09 for seminal vesicle invasion (p = 0.011) and 0.06 for lymph node involvement (p = 0.120). Using Gleason scores derived from targeted biopsy compared to systematic biopsy provided an additional predictive value of organ confined disease (Δ AUC 0.07, p = 0.003) and extraprostatic extension (Δ AUC 0.07, p = 0.048) at radical prostatectomy with the MSKCC nomogram. Similar results were obtained using the Partin nomogram.

CONCLUSIONS

Magnetic resonance imaging alone or in addition to standard clinical nomograms provides significant additional predictive ability of adverse pathology at the time of radical prostatectomy. This information can be greatly beneficial to urologists for preoperative planning and for counseling patients regarding the risks of future therapy.

Follow-up of negative MRI-targeted prostate biopsies: when are we missing cancer?

INTRODUCTION

Multiparametric magnetic resonance imaging (mpMRI) has improved clinicians' ability to detect clinically significant prostate cancer (csPCa). Combining or fusing these images with the real-time imaging of transrectal ultrasound (TRUS) allows urologists to better sample lesions with a targeted biopsy (Tbx) leading to the detection of greater rates of csPCa and decreased rates of low-risk PCa. In this review, we evaluate the technical aspects of the mpMRI-guided Tbx procedure to identify possible sources of error and provide clinical context to a negative Tbx.

METHODS

A literature search was conducted of possible reasons for false-negative TBx. This includes discussion on false-positive mpMRI findings, termed "PCa mimics," that may incorrectly suggest high likelihood of csPCa as well as errors during Tbx resulting in inexact image fusion or biopsy needle placement.

RESULTS

Despite the strong negative predictive value associated with Tbx, concerns of missed disease often remain, especially with MR-visible lesions. This raises questions about what to do next after a negative Tbx result. Potential sources of error can arise from each step in the targeted biopsy process ranging from "PCa mimics" or technical errors during mpMRI acquisition to failure to properly register MRI and TRUS images on a fusion biopsy platform to technical or anatomic limits on needle placement accuracy.

CONCLUSIONS

A better understanding of these potential pitfalls in the mpMRI-guided Tbx procedure will aid interpretation of a negative Tbx, identify areas for improving technical proficiency, and improve both physician understanding of negative Tbx and patient-management options.

"Super-active surveillance": MRI ultrasound fusion biopsy and ablation for less invasive management of prostate cancer

Multiparametric magnetic resonance imaging (mpMRI) of the prostate has allowed clinicians to better visualize and target suspicious lesions during biopsy. Targeted prostate biopsies give a more accurate representation of the true cancer volume and stage so that appropriate treatment or active surveillance can be selected. Advances in technology have led to the development of MRI and ultrasound fusion platforms used for targeted biopsies, monitoring cancer progression, and more recently for the application of focal therapy. Lesions visualized on mpMRI can be targeted for ablation with a variety of energy sources employed under both local and general anesthesia. Focal ablation may offer an alternative option for treating prostate cancer as compared to the well-established interventions of whole-gland radiation or prostatectomy. Focal ablation may also be an option for patients on active surveillance who wish to be even more "active" in their surveillance. In this review, we describe the advancements and development of fusion biopsies, the rationale behind focal therapy, and introduce focal ablative techniques for indolent prostate cancers ("super-active surveillance"), including cryoablation and focal laser ablation (FLA) and the subsequent MRI/biopsy surveillance.

WECHE: a novel hematopoietic regulatory factor

Previously, we described AGM-derived endothelial cell lines that either inhibited or permitted the development of erythroid or B cells. We utilized a differential gene expression method to isolate a chemokine, termed WECHE, from one of these cell lines. WECHE inhibited the formation of erythroid cells but had no effect on either myeloid or B cell formation. WECHE repressed BFU-E development from either mouse fetal liver or bone marrow progenitor cells but had no effect on colony formation induced by IL-3 or IL-7. WECHE reduced HPP-CFC production from fetal liver-derived stem cells. WECHE hindered the growth of yolk sac-derived endothelial cells. WECHE was also chemotactic for bone marrow cells. Thus, WECHE is a novel chemokine that regulates hematopoietic differentiation.

Gene expression analysis by transcript profiling coupled to a gene database query

We describe an mRNA profiling technique for determining differential gene expression that utilizes, but does not require, prior knowledge of gene sequences. This method permits high-throughput reproducible detection of most expressed sequences with a sensitivity of greater than 1 part in 100,000. Gene identification by database query of a restriction endonuclease fingerprint, confirmed by competitive PCR using gene-specific oligonucleotides, facilitates gene discovery by minimizing isolation procedures. This process, called GeneCalling, was validated by analysis of the gene expression profiles of normal and hypertrophic rat hearts following in vivo pressure overload.