Faculty Bibliography

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.

Purpose: Percutaneous thermal ablation (PTA) is a minimally-invasive, nephron-sparing alternative to surgery for patients with small renal cancers. We examined short- and long-term complications and disease-specific survival in older adults with small renal cancers who received partial (PN) nephrectomy, radical nephrectomy (RN) or PTA. Materials: In the linked Surveillance, Epidemiology and End Results-Medicare dataset we identified patients age 66 or older who received PN, RN or PTA within 6 months of diagnosis of a clinically-staged T1a renal cancer in 2006-2011. Follow-up for survival and cause of death was available through 2012. Complications assessed at 30 days and 31-365 days post procedure based on Medicare claims included renal insufficiency and periprocedural and cardiovascular complications. Associations between procedure type and complications were estimated in propensity score-matched logistic regression models. Associations with cancer-specific survival (CSS) were estimated in propensity score-adjusted, competing-risk models. Results: There were 4,508 patients with cT1a renal cancer, of whom 469 (10%) had PTA, 1,673 (37%) PN and 2,366 (53%) RN. Patients who had PTA were older and had greater comorbidity than those treated surgically (p<0.0001). At 30 days, rates of acute renal failure, structural kidney injury, cardiovascular complications and other periprocedural complications were significantly lower with PTA than PN or RN (adjusted odds ratios [AOR] 0.10-0.52, p<0.05). Rates of cardiovascular and renal structural complications at 1 year were similar across procedure types. PTA was associated with a lower risk of renal insufficiency in days 31-365 compared with RN (AOR 0.56, 95% CI 0.34-0.93, p< 0.05), but not with PN. At 46 months median follow-up, there were 112 deaths due to kidney cancer. Cancer-specific survival did not vary by procedure type. Conclusions: In a population-based cohort of older adults, PTA was associated with a lower risk of early complications than RN or PN, and a lower rate of long-term renal insufficiency than RN. PTA may be safer than surgery for well-selected patients, with no detriment to oncologic outcomes at nearly 4 years median follow-up

BACKGROUND: To assess associations between whole-lesion apparent diffusion coefficient (ADC) metrics and pathologic findings of Likert score 3 prostate lesions at MRI/ultrasound fusion targeted biopsy. METHODS: This retrospective Institutional Review Board-approved study received a waiver of consent. We identified patients receiving a highest lesion score of 3 on 3 Tesla multiparametric MRI reviewed by a single experienced radiologist using a 5-point Likert scale and who underwent fusion biopsy. A total of 188 score 3 lesions in 158 patients were included. Three-dimensional volumes-of-interest encompassing each lesion were traced on ADC maps. Logistic regression was used to predict biopsy results based on whole-lesion ADC metrics and patient biopsy history. Biopsy yield was compared between metrics. RESULTS: By lesion, targeted biopsy identified tumor in 22.3% and Gleason score (GS) > 6 tumor in 8.5%, although results varied by biopsy history: biopsy-naive (n = 80), 20.0%/8.8%; prior negative biopsy (n = 53), 9.4%/1.9%; prior positive biopsy (n = 55): 40.0%/14.5%. Biopsy history, whole-lesion mean ADC, whole-lesion ADC10-25 , and whole-lesion ADC25-50 were each significantly associated with tumor or GS > 6 tumor at fusion biopsy (P 6 tumor, which was significantly higher (P < 0.001) than specificity of PSA (17.5%) at identical sensitivity. CONCLUSION: For score 3 lesions in patients without prior negative biopsy, whole-lesion ADC metrics help detect GS > 6 cancer while avoiding negative biopsies. However, deferral of fusion biopsy may be considered for score 3 lesions in patients with prior negative biopsy (without applying whole-lesion ADC metrics) given exceedingly low ( approximately 2%) frequency of GS > 6 tumor in this group. J. Magn. Reson. Imaging 2015.

OBJECTIVES: To characterize patterns of imaging surveillance after nephrectomy in a population-based cohort of older patients with kidney cancer. PATIENTS AND METHODS: Using the Surveillance, Epidemiology and End Results (SEER)-Medicare database, we identified patients aged >/=66 years who underwent partial or radical nephrectomy for localized kidney cancer diagnosed between 2000 and 2009. Primary outcomes were chest imaging (X-ray or computed tomography [CT]) and abdominal imaging (CT, MRI or ultrasonography) in Medicare claims from 4 to 36 months after surgery. We estimated the frequency of imaging in three time periods (postoperative months 4-12, 13-24, 25-36), stratified by tumour stage. Repeated-measures logistic regression was used to identify the patient and disease characteristics associated with imaging. RESULTS: Rates of chest imaging were 65-80%, with chest X-ray surpassing CT in each time period. Rates of abdominal imaging were 58-76%, and cross-sectional imaging was more common than ultrasonography in each time period. Use of cross-sectional chest and abdominal imaging increased over time, while the use of chest X-ray decreased (P < 0.01). Ultrasonography use remained stable for patients with T1 and T2 disease, but the rate of use decreased in patients with T3 disease (P < 0.05). Rates of chest and abdominal imaging increased with tumour stage (P < 0.001). CONCLUSIONS: Patterns of imaging suggest possible overuse in patients at low risk of recurrence and underuse in those at greater risk. New surveillance imaging guidelines may reduce unwarranted variability and promote risk-based, cost-effective management after nephrectomy.

INTRODUCTION: There is increasing interest in using imaging in the detection and localization of prostate cancer (PCa). Both multiparametric magnetic resonance imaging (mpMRI) and HistoScanning (HS) have been independently evaluated in the detection and localization of PCa. We undertook a prospective, blinded comparison of mpMRI and HS for cancer localization among men undergoing radical prostatectomy. METHODS: Following approval by the institutional review board, men scheduled to undergo radical prostatectomy, who had previously undergone mpMRI at our institution, were offered inclusion in the study. Those consenting underwent preoperative HS following induction of anesthesia; mpMRI, HS, and surgical step-section pathology were independently read by a single radiologist, urologist, and pathologist, respectively, in a blinded fashion. Disease maps created by each independent reader were compared and evaluated for concordance by a 5 persons committee consisting of 2 urologists, 2 pathologists, and 1 radiologist. Logistic regression for correlated data was used to assess and compare mpMRI and HS in terms of diagnostic accuracy for cancer detection. Generalized estimating equations based on binary logistic regression were used to model concordance between reader opinion and the reference standard assessment of the same lesion site or region as a function of imaging modality. RESULTS: Data from 31/35 men enrolled in the trial were deemed to be evaluable. On evaluation of cancer localization, HS identified cancer in 36/78 (46.2%) regions of interest, as compared with 41/78 (52.6%) on mpMRI (P = 0.3968). The overall accuracy, positive predictive value, negative predictive value, and specificity for detection of disease within a region of interest were significantly better with mpMRI as compared with HS. HS detected 36/84 (42.9%) cancer foci as compared with 42/84 (50%) detected by mpMRI (P = 0.3678). Among tumors with Gleason score>6, mpMRI detected 19/22 (86.4%) whereas HS detected only 11/22 (50%, P = 0.0078). Similarly, among tumors>10mm in maximal diameter, mpMRI detected 28/34 (82.4%) whereas HS detected only 19/34 (55.9%, P = 0.0352). CONCLUSION: In our institution, the diagnostic accuracy of HS was inferior to that of mpMRI in PCa for PCa detection and localization. Although our study warrants validation from larger cohorts, it would suggest that the HS protocol requires further refinement before clinical implementation.

Background: Cisplatin-based chemotherapy before radical cystectomy (RC) improves survival in pts with MIBC. DD-GC therapy is active in the metastatic setting [6 cycles (cy), 18 months median survival; Bamias et al, 2012)] and as neo therapy (3 cy, 44% < pT1 rate; Plimack et al, 2014), but the optimal dose and number of cy of neo therapy has not been defined. We prospectively evaluated the activity and safety of 6 cy of neo DD-GC over 12 weeks in MIBC. Methods: Pts with T2-4aN0 disease received six 14-day cy of DD-GC as follows: G 2500 mg/m2 day 1, C 35 mg/m2 days 1 and 2, pegfilgrastim day 3. RC with bilateral pelvic lymph node dissection was planned within 8 weeks of DD-GC completion, regardless of clinical response. The primary endpoint was pathologic response ( < pT1) rate > 55% (exact Binomial one-sided test). Pts not undergoing RC were deemed non-responders regardless of clinical stage after DD-GC. Pts receiving < 3 cy were inevaluable and replaced. All pts were evaluable for toxicity. Results: 49 pts (40 male) were enrolled. Median age was 64 (range: 37-78). Clinical stage was T2N0 (32 pts), T3N0 (12 pts), and T4aN0 (5 pts). Toxicities resulting in cy delay and/or dose modifications included thrombocytopenia (9 pts), renal insufficiency (5 pts), vascular access complication (2 pts), ototoxicity (1 pt), significant urinary symptoms (1 pt), and transient ischemic attack (1 pt). Three pts are inevaluable for the primary endpoint ( < 3 cy). As of 9/7/15, 2 pts are pending RC. Of the 44 pts evaluable for response to date, 31 completed 6 cy of DD-GC, 6 pts completed 5, 3 pts completed 4, and 4 pts completed 3 (median: 6 cy). The median time to RC was 46 days. Four of 44 pts did not undergo RC (consent withdrawal, pt refusal, disease progression prior to RC, death from other causes). Trial accrual has closed with completion of clinical and pathologic data expected by 11/1/15. Of 40 pts with RC pathology available to date, 24 (60%) were < pT1 and 7 (18%) were pT0. Conclusions: Six cy of DD-GC is an active well-tolerated neo chemotherapy regimen in pts with MIBC. The pathologic response rate is encouraging. Thrombocytopenia was the most common toxicity resulting in cy delays/dose modifications

BACKGROUND: MRI-ultrasound fusion-targeted prostate biopsy (MRF-TB) may improve detection of prostate cancer (PCa) in men presenting for prostate biopsy. We report clinical outcomes of 12-core systematic biopsy (SB) and MRF-TB in men presenting for primary biopsy and further describe pathological characteristics of cancers detected by SB and not by MRF-TB. MATERIALS & METHODS: Clinical outcomes of 435 consecutive men who underwent pre-biopsy mpMRI followed by MRF-TB and SB at our institution between June 2012 and March 2015 were captured in an IRB-approved database Clinical characteristics, biopsy results and MRI suspicion scores (mSS) were queried from the database. RESULTS: Among 370 men (mean age 64+/-8.5 years; mean PSA 6.8, SEM 0.3 ng/mL) who met inclusion criteria, PCa was detected in 200 (54.1%) cases. Cancer detection rates for SB and MRF-TB were 47.3% and 43.5%, respectively (p = 0.104). MRF-TB detected more Gleason score >/=7 cancers than SB (114/128 (89.1%) vs 95/128 (74.2%), respectively, p = 0.008). Of 39 cancers detected by SB, but not by MRF-TB, 32/39 (82.1%) demonstrated Gleason 6 disease, and 24/39 (61.5%) and 32/39 (82.1%) were clinically insignificant by Epstein and UCSF CAPRA (score