Lars A.R. Reisæter

Observation Should be Considered as an Alternative in Management of Renal Masses in Older and Comorbid Patients

BACKGROUND Renal masses diagnosed in older and comorbid patients represent a challenge with regard to treatment. OBJECTIVE To evaluate clinical outcome and tumor progression in patients with renal masses managed by observation due to age and comorbidity. DESIGN, SETTING, AND PARTICIPANTS The medical records of 63 consecutive patients with renal masses primarily managed by observation during 2002-2007 were reviewed retrospectively and analyzed. The mean age for all patients at diagnosis was 76.6 yr, and 59% were male. Mean tumor size was 4.3 cm in diameter at diagnosis. Of these, 30% had Eastern Cooperative Oncology Group performance status (PS) of 2 or 3, 78% were American Society of Anesthesiologists (ASA) class 3, and the patients had a mean of 2.8 other medical conditions. MEASUREMENTS Registration of age, ASA class, PS, comorbid conditions, computed tomography scans, primary tumor size, tumor growth rate, pathology parameters, observation time, survival time. RESULTS AND LIMITATIONS Five-year overall survival (OS) and cancer-specific survival (CSS) rates were 42.8% and 93.3%, respectively. For tumors < or =4.0 cm in size, 5-yr CSS was 100%. Nine patients received delayed radical treatment, none of whom had later progression of the disease. In 18 patients histopathologic diagnosis of the renal masses were available, and in 15 patients (83%) renal cell carcinoma (RCC) was verified. The annual growth rate was <1cm/yr in 85.4% of the cases. In tumors < or =4.0 cm, only 1 of 27 tumors (3.7%) grew faster than 1cm/yr. CONCLUSIONS Management of renal masses by observation among older and comorbid patients seems to give acceptable results with regard to OS and CSS rates after 5 yr. The risk of disease progression is significantly higher in patients with larger sized renal masses (>4 cm). Thus, selection for observation in this group has to be stricter than in a group of patients with smaller sized renal masses (< or =4.0 cm).

1.5-T multiparametric MRI using PI-RADS: a region by region analysis to localize the index-tumor of prostate cancer in patients undergoing prostatectomy

Background The use of multiparametric magnetic resonance imaging (mpMRI) to detect and localize prostate cancer has increased in recent years. In 2010, the European Society of Urogenital Radiology (ESUR) published guidelines for mpMRI and introduced the Prostate Imaging Reporting and Data System (PI-RADS) for scoring the different parameters. Purpose To evaluate the reliability and diagnostic performance of endorectal 1.5-T mpMRI using the PI-RADS to localize the index tumor of prostate cancer in patients undergoing prostatectomy. Material and Methods This institutional review board IRB-approved, retrospective study included 63 patients (mean age, 60.7 years, median PSA, 8.0). Three observers read mpMRI parameters (T2W, DWI, and DCE) using the PI-RADS, which were compared with the results from whole-mount histopathology that analyzed 27 regions of interest. Inter-observer agreement was calculated as well as sensitivity, specificity, positive predictive value (PPV), and negative predicted value (NPV) by dichotomizing the PI-RADS criteria scores ≥3. A receiver-operating curve (ROC) analysis was performed for the different MR parameters and overall score. Results Inter-observer agreement on the overall score was 0.41. The overall score in the peripheral zone achieved sensitivities of 0.41, 0.60, and 0.55 with an NPV of 0.80, 0.84, and 0.83, and in the transitional zone, sensitivities of 0.26, 0.15, and 0.19 with an NPV of 0.92, 0.91, and 0.92 for Observers 1, 2, and 3, respectively. The ROC analysis showed a significantly increased area under the curve (AUC) for the overall score when compared to T2W alone for two of the three observers. Conclusion 1.5 T mpMRI using the PI-RADS to localize the index tumor achieved moderate reliability and diagnostic performance.

F18-FDG-PET for recurrent differentiated thyroid cancer: a systematic meta-analysis

Background Positron emission tomography (PET) with fluor-18-deoxy-glucose (FDG) is widely used for diagnosing recurrent or metastatic disease in patients with differentiated thyroid cancer (DTC). Purpose To assess the diagnostic accuracy of FDG-PET for DTC in patients after ablative therapy. Material and Methods A systematic search was conducted in Medline/PubMed, EMBASE, Cochrane Library, Web of Science, and Open Grey looking for all English-language original articles on the performance of FDG-PET in series of at least 20 patients with DTC having undergone ablative therapy including total thyroidectomy. Diagnostic performance measures were pooled using Reitsma’s bivariate model. Results Thirty-four publications between 1996 and 2014 met the inclusion criteria. Pooled sensitivity and specificity were 79.4% (95% confidence interval [CI], 73.9–84.1) and 79.4% (95% CI, 71.2–85.4), respectively, with an area under the curve of 0.858. Conclusion F18-FDG-PET is a useful method for detecting recurrent DTC in patients having undergone ablative therapy.

Crohn's disease evaluated with magnetic resonance enteroclysis: diagnostic performance of experienced and inexperienced readers before and after training.

Background: Magnetic resonance enteroclysis (MRE) is suggested to become the preferred radiological method in small-bowel Crohns disease (CD). However, the performance of inexperienced readers may influence the diagnostic value of the method and has not been previously investigated. Purpose: To compare readings of MRE in small-bowel CD performed by experienced and inexperienced readers before and after training. Material and Methods: One experienced radiologist (observer 1) and two trainees (observers 2 and 3) reviewed 60 MRE examinations. A second reading was performed after training. Bowel wall thickness (BWT), ulcers (BWU), stenosis (BWS), fistulas (FIS), and abscesses (ABS) were evaluated. A reference standard based on clinical records was established. Results: BWT in the terminal ileum was evaluated with high diagnostic performance (sensitivity: observer 1, 83%; observer 2, 72%; observer 3, 78%). Only BWU was diagnosed with a higher sensitivity by observer 1 (78% vs. 33% and 39%, respectively; P=0.02). False-positive findings for BWT in the jejunum (observer 2: 7; observer 3: 4) and fistulas and abscesses (observer 2: 11/5; observer 3: 5/4) were made by the trainees. Interobserver agreement in the jejunum was poor (observer 1/observer 2: κ=0.23; observer 1/observer 3: κ=−0.03) and in the ileum good (observer 1/observer 2: κ=0.78; observer 1/observer 3: κ=0.73). After training, evaluation of BWU (observer 2: 56%, P=0.22; observer 3: 44%, P=0.03), BWT (observer 2: 2; observer 3: 2), and interobserver agreement in the jejunum improved (observer 1/observer 2: κ=0.66; observer 1/observer 3: κ=0.66). However, the number of diagnosed fistulas and abscesses remained high. Conclusion: Before training, most findings of Crohns disease in the terminal ileum were evaluated with high diagnostic performance by all readers. However, the inexperienced readers evaluated BWU with a low sensitivity and overestimated the number of FIS, number of ABS, and increased BWT in the jejunum. After training, evaluation by inexperienced readers of BWU and increased BWT in the jejunum improved.

Contemporary external validation of the Leibovich model for prediction of progression after radical surgery for clear cell renal cell carcinoma

Abstract Objective.The aim of this study was to externally validate in an up-to-date setting the predictive ability of the model for recurrence after radical treatment of clear cell renal cell carcinoma (CCRCC) published by Leibovich in 2003. Materials and methods. The study included a total of 386 consecutive patients with CCRCC between January 1997 and May 2013, treated with partial or radical nephrectomy. All patients were scored with points between 0 and 11, and further subdivided into low-, intermediate- and high-risk groups according to the original paper. Well-recognized statistical methods for the evaluation of Cox’s proportional hazard-based prognostic models were applied. To validate the discriminative ability, Harrell’s concordance (c) index and hazard ratios (HRs) between risk groups were used, and calibration was graphically explored. Results.The 10 year recurrence-free survival rates for the low-, intermediate- and high-risk groups were 87.3%, 63.8% and 19.8%, respectively Harrell’s c index was 0.864. The HRs across risk groups for the intermediate- and high-risk groups were 5.29 and 21.56, respectively, with the low-risk group as a reference category. A gross comparison of the survival estimates between the patients showed an overall similarity. However, differences within the intermediate- and high-risk groups were seen in the first year of follow-up. Conclusions.The Leibovich model seems to discriminate well between risk groups, but for the intermediate- and high-risk groups the calibration is not optimal. This study validates the model in a present-day Nordic patient population. The model can be used as a risk stratification tool for follow-up after radical treatment of CCRCC.

Real-life use of diagnostic biopsies before treatment of kidney cancer: results from a Norwegian population-based study

Abstract Objective: Interest in renal mass biopsies (RMBs) has increased in recent years. However, most publications are low-volume and/or single-center studies, so their generalizability is questionable. The aim of this study was to describe population-based, real-life use of diagnostic RMBs for localized and advanced kidney cancer (KC). Materials and methods: All KC patients diagnosed during 2008–2013 extracted from the database at the Cancer Registry of Norway were included. Relationships with outcome were analyzed using multivariate logistic regression and competing risks analyses. Results: Of patients treated radically for localized KC, a pretreatment RMB was used in 8.4%. For similar patients treated by observation only, the rate increased from 29.3% to 60.7% during the study period. Tumor size ≤4 cm, another malignancy, multiple tumors, old age (≥ 80 years) and second study half were independent RMB predictors. Competing risks analysis showed that among radically treated patients with localized KC, those who had undergone an RMB had a higher risk of dying of other diseases. In patients with advanced KC, biopsy was used in 54.5%, and is increasing. Study limitations include a lack of data on benign tumors, comorbidity and performance status. Conclusions: For localized KC, the use of RMBs in Norway is in line with current guidelines. Because real-world data on RMB use are scarce, this study is useful for benchmarking in future studies. Furthermore, the study shows that fewer patients with advanced KC are treated without histopathological verification, and biopsies seem to have an increasing role in tailoring treatment.

Optimising preoperative risk stratification tools for prostate cancer using mpMRI

AbstractPurposeTo improve preoperative risk stratification for prostate cancer (PCa) by incorporating multiparametric MRI (mpMRI) features into risk stratification tools for PCa, CAPRA and D’Amico.Methods807 consecutive patients operated on by robot-assisted radical prostatectomy at our institution during the period 2010–2015 were followed to identify biochemical recurrence (BCR). 591 patients were eligible for final analysis. We employed stepwise backward likelihood methodology and penalised Cox cross-validation to identify the most significant predictors of BCR including mpMRI features. mpMRI features were then integrated into image-adjusted (IA) risk prediction models and the two risk prediction tools were then evaluated both with and without image adjustment using receiver operating characteristics, survival and decision curve analyses.Results37 patients suffered BCR. Apparent diffusion coefficient (ADC) and radiological extraprostatic extension (rEPE) from mpMRI were both significant predictors of BCR. Both IA prediction models reallocated more than 20% of intermediate-risk patients to the low-risk group, reducing their estimated cumulative BCR risk from approximately 5% to 1.1%. Both IA models showed improved prognostic performance with a better separation of the survival curves.ConclusionIntegrating ADC and rEPE from mpMRI of the prostate into risk stratification tools improves preoperative risk estimation for BCR.Key points• MRI-derived features, ADC and EPE, improve risk stratification of biochemical recurrence. • Using mpMRI to stratify prostate cancer patients improves the differentiation between risk groups. • Using preoperative mpMRI will help urologists in selecting the most appropriate treatment.

Intensity-based volumetric registration of magnetic resonance images and whole-mount sections of the prostate

OBJECTIVE Magnetic Resonance Imaging (MRI) of the prostate provides useful in vivo diagnostic tissue information such as tumor location and aggressiveness, but ex vivo histopathology remains the ground truth. There are several challenges related to the registration of MRI to histopathology. We present a method for registration of standard clinical T2-weighted MRI (T2W-MRI) and transverse histopathology whole-mount (WM) sections of the prostate. METHODS An isotropic volume stack was created from the WM sections using 2D rigid and deformable registration combined with linear interpolation. The prostate was segmented manually from the T2W-MRI volume and registered to the WM section volume using a combination of affine and deformable registration. The method was evaluated on a set of 12 patients who had undergone radical prostatectomy. Registration accuracy was assessed using volume overlap (Dice Coefficient, DC) and landmark distances. RESULTS The DC was 0.94 for the whole prostate, 0.63 for the peripheral zone and 0.77 for the remaining gland. The landmark distances were on average 5.4 mm. CONCLUSION The volume overlap for the whole prostate and remaining gland, as well as the landmark distances indicate good registration accuracy for the proposed method, and shows that it can be highly useful for registering clinical available MRI and WM sections of the prostate.