Faculty Bibliography

PURPOSE: The aim of this study was to conduct a prospective pilot study comparing the diagnostic performance of MRI alone and F-FDG simultaneous PET/MRI using a diuresis protocol in bladder cancer patients. METHODS: Twenty-two bladder cancer patients underwent F-FDG PET/MRI, using intravenous furosemide and oral hydration for bladder clearance. A radiologist scored probability of tumor in 3 locations (urinary bladder, pelvic lymph nodes, nonnodal pelvis) using 1- to 3-point scale (1 = negative, 2 = equivocal, 3 = definite tumor). A nuclear medicine physician reviewed fused PET/MRI images, after which scores were reassigned based on combined findings. Follow-up pathologic and imaging data served as reference. Performances of MRI alone and PET/MRI were compared. RESULTS: Of these patients, 82%, 38%, and 18% were positive for bladder, pelvic nodal, and nonnodal pelvic tumor, respectively. At a score of 3, PET/MRI exhibited greater accuracy for detection of bladder tumor (86% vs 77%), metastatic pelvic lymph nodes (95% vs 76%), and nonnodal pelvic malignancy (100% vs 91%). In the bladder, PET changed the level of suspicion in 36% of patients (50% increased suspicion, 50% decreased suspicion), with 75% of these changes deemed correct based on reference standard. For pelvic lymph nodes, PET changed suspicion in 52% (36% increase, 64% decrease), with 95% of changes deemed correct. For nonnodal pelvis, PET changed suspicion in 9% (100% increase), with 100% deemed correct. CONCLUSIONS: Additional PET information helped to appropriately determine level of suspicion in multiple anatomic sites for otherwise equivocal findings on MRI alone. Although requiring larger studies, findings suggest a possible role for simultaneous PET/MRI to assist bladder cancer management.

BACKGROUND: Renal cell carcinoma forming a venous tumor thrombus (VTT) in the inferior vena cava (IVC) has a poor prognosis. Recent investigations have been focused on prognostic markers of survival. Thrombus consistency (TC) has been proposed to be of significant value but yet there are conflicting data. The aim of this study is to test the effect of IVC VTT consistency on cancer specific survival (CSS) in a multi-institutional cohort. METHODS: The records of 413 patients collected by the International Renal Cell Carcinoma-Venous Thrombus Consortium were retrospectively analyzed. All patients underwent radical nephrectomy and tumor thrombectomy. Kaplan-Meier estimate and Cox regression analyses investigated the impact of TC on CSS in addition to established clinicopathological predictors. RESULTS: VTT was solid in 225 patients and friable in 188 patients. Median CSS was 50 months in solid and 45 months in friable VTT. TC showed no significant association with metastatic spread, pT stage, perinephric fat invasion, and higher Fuhrman grade. Survival analysis and Cox regression rejected TC as prognostic marker for CSS. CONCLUSIONS: In the largest cohort published so far, TC seems not to be independently associated with survival in RCC patients and should therefore not be included in risk stratification models. J. Surg. Oncol. (c) 2016 Wiley Periodicals, Inc.

OBJECTIVES: To evaluate the cancer detection rates (CDR) for men undergoing 12 core systematic prostate biopsy with negative prebiopsy mpMRI (NegMR). MATERIALS & METHODS: Clinical data from consecutive men undergoing prostate biopsy with prebiopsy 3T mpMRI from December 2011 to August 2014 were reviewed from an IRB approved prospective database. Prebiopsy mpMRI was read by a single radiologist and men with NegMR prior to biopsy were identified for this analysis. Clinical features, CDR, and NPV rates were summarized. RESULTS: Seventy five men underwent SPB with a NegMRI during the study period. For the entire cohort, men with no prior biopsy, men with prior negative biopsy, and men enrolled in active surveillance protocols, overall CDR was 18.7%, 13.8%, 8.0% and 38.1%, respectively, and detection of Gleason sum >/= 7 (GS>/=7) cancer was 1.3%, 0%, 4.0% and 0%, respectively. The NPV for all cancers was 81.3%, 86.2%, 92.0%, and 61.9%, and for GS>/=7 cancer was 98.7%, 100%, 96.0% and 100%, respectively. CONCLUSIONS: Negative prebiopsy mpMRI confers an overall NPV of 82% on 12 core biopsy for all cancer and 98% for GS>/=7. Based upon biopsy indication, these findings assist in prebiopsy risk stratification for detection of high risk disease and may provide guidance in the decision to pursue biopsy

OBJECTIVE: The purpose of this article is to compare the effectiveness of a treatment algorithm for small renal tumors incorporating the nephrometry score, a renal tumor anatomy scoring system developed by urologists, with the current standard of uniformly recommended partial nephrectomy in patients with mild-to-moderate chronic kidney disease (CKD). MATERIALS AND METHODS: We developed a state-transition microsimulation model to project life expectancy (LE) in hypothetic patients with baseline mild or moderate CKD undergoing treatment of small renal masses. Our model incorporated the nephrometry score, which is predictive of postsurgical renal function loss. The two tested strategies were uniform treatment with partial nephrectomy and selective treatment based on nephrometry score and CKD stage, including percutaneous ablation for CKD stages 2 or 3a and intermediate-to-high nephrometry score or stage 3b CKD and any nephrometry score; otherwise, partial nephrectomy was assumed for other CKD stages and nephrometry scores. The model accounted for benign and malignant lesions, renal function decline, recurrence, and metastatic disease rates specific to each treatment, mortality by CKD stage, and comorbidities. Sensitivity analysis tested the stability of results when varying key parameters. RESULTS: Selective treatment with partial nephrectomy resulted in an average LE benefit of 0.48 year (95% interpercentile range, 0.42-0.54 year) in 65-year-old men and 0.37 year (95% interpercentile range, 0.30-0.43 year) in 65-year-old women relative to nondiscriminatory surgery, due to worsening CKD and cardiovascular mortality associated with partial nephrectomy. Model results were most sensitive to the rate of renal function decline and CKD-related mortality. CONCLUSION: Nephron-sparing treatment selection for small renal masses based on nephrometry score may improve LE in patients with mild or moderate CKD.

Purpose Pre-operative three-dimensional (3D) printed renal malignancy models are tools with potential benefits in surgical training and patient education [1,2]. Most importantly, 3D models may facilitate surgical planning by allowing surgeons to assess tumor complexity as well as the relationship of the tumor to major anatomic structures [3]. The objective of this study was to evaluate this impact. Methods Imaging was obtained from an IRB approved, prospectively collected database of multiparametric magnetic resonance imaging (MRI) of renal masses. Ten cases eligible for elective partial nephrectomy were retrospectively selected. High-fidelity models were 3D printed in multiple colors based on T1 images (Fig. 1). Cases were reviewed by three attending surgeons and six senior residents with imaging alone and in addition to the 3D model. A standardized questionnaire was developed to capture the planned surgical approach and intraoperative technique in both sessions. Results Surgical approach was changed in 20 % of decisions, intraoperative considerations were changed in 40 % (Fig. 2). Thirty percent and 23 % of decisions in the attending and resident groups, respectively, were altered by the 3D model. Overall, every case was modified with this additional information. All participants reported that the models helped plan the surgical approach for partial nephrectomy. Most reported improved comprehension of anatomy and confidence in surgical plan. Half reported that the 3D printed model altered their surgical plan significantly. Due to use of T1 images, reconstruction of calyces and tertiary blood vessels were limited: 8 of the 9 participants desired more information regarding these structures. (Figure presented) Conclusion Utilization of 3D modeling may aid in pre-operative and intra-operative planning for both attending and resident surgeons. While 3D models with MR imaging is feasible, computed tomography (CT) imaging may provide additional anatomical information. Future study is required to prospectively assess the utility of models and pre-operative planning and intra-operative guidance

OBJECTIVE: The purpose of this study was to determine whether qualitative and quantitative MRI feature analysis is useful for differentiating type 1 from type 2 papillary renal cell carcinoma (PRCC). MATERIALS AND METHODS: This retrospective study included 21 type 1 and 17 type 2 PRCCs evaluated with preoperative MRI. Two radiologists independently evaluated various qualitative features, including signal intensity, heterogeneity, and margin. For the quantitative analysis, a radiology fellow and a medical student independently drew 3D volumes of interest over the entire tumor on T2-weighted HASTE images, apparent diffusion coefficient parametric maps, and nephrographic phase contrast-enhanced MR images to derive first-order texture metrics. Qualitative and quantitative features were compared between the groups. RESULTS: For both readers, qualitative features with greater frequency in type 2 PRCC included heterogeneous enhancement, indistinct margin, and T2 heterogeneity (all, p < 0.035). Indistinct margins and heterogeneous enhancement were independent predictors (AUC, 0.822). Quantitative analysis revealed that apparent diffusion coefficient, HASTE, and contrast-enhanced entropy were greater in type 2 PRCC (p < 0.05; AUC, 0.682-0.716). A combined quantitative and qualitative model had an AUC of 0.859. Qualitative features within the model had interreader concordance of 84-95%, and the quantitative data had intraclass coefficients of 0.873-0.961. CONCLUSION: Qualitative and quantitative features can help discriminate between type 1 and type 2 PRCC. Quantitative analysis may capture useful information that complements the qualitative appearance while benefiting from high interobserver agreement.

BACKGROUND: Increasing evidence supports the use of magnetic resonance imaging (MRI)-ultrasound fusion-targeted prostate biopsy (MRF-TB) to improve the detection of clinically significant prostate cancer (PCa) while limiting detection of indolent disease compared to systematic 12-core biopsy (SB). OBJECTIVE: To compare MRF-TB and SB results and investigate the relationship between biopsy outcomes and prebiopsy MRI. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of a prospectively acquired cohort of men presenting for prostate biopsy over a 26-mo period. A total of 601 of 803 consecutively eligible men were included. INTERVENTIONS: All men were offered prebiopsy MRI and assigned a maximum MRI suspicion score (mSS). Men with an MRI abnormality underwent combined MRF-TB and SB. OUTCOMES: Detection rates for all PCa and high-grade PCa (Gleason score [GS] >/=7) were compared using the McNemar test. RESULTS AND LIMITATIONS: MRF-TB detected fewer GS 6 PCas (75 vs 121; p<0.001) and more GS >/=7 PCas (158 vs 117; p<0.001) than SB. Higher mSS was associated with higher detection of GS >/=7 PCa (p<0.001) but was not correlated with detection of GS 6 PCa. Prediction of GS >/=7 disease by mSS varied according to biopsy history. Compared to SB, MRF-TB identified more GS >/=7 PCas in men with no prior biopsy (88 vs 72; p=0.012), in men with a prior negative biopsy (28 vs 16; p=0.010), and in men with a prior cancer diagnosis (42 vs 29; p=0.043). MRF-TB detected fewer GS 6 PCas in men with no prior biopsy (32 vs 60; p<0.001) and men with prior cancer (30 vs 46; p=0.034). Limitations include the retrospective design and the potential for selection bias given a referral population. CONCLUSIONS: MRF-TB detects more high-grade PCas than SB while limiting detection of GS 6 PCa in men presenting for prostate biopsy. These findings suggest that prebiopsy multiparametric MRI and MRF-TB should be considered for all men undergoing prostate biopsy. In addition, mSS in conjunction with biopsy indications may ultimately help in identifying men at low risk of high-grade cancer for whom prostate biopsy may not be warranted. PATIENT SUMMARY: We examined how magnetic resonance imaging (MRI)-targeted prostate biopsy compares to traditional systematic biopsy in detecting prostate cancer among men with suspicion of prostate cancer. We found that MRI-targeted biopsy detected more high-grade cancers than systematic biopsy, and that MRI performed before biopsy can predict the risk of high-grade cancer.