A 7-Year-Old Boy with Fever and Dark Urine.

A 7-Year-Old Boy with Fever and Dark UrineA 7-year-old boy with surgically repaired tetralogy of Fallot presented for evaluation of fever and dark urine. How do you approach the evaluation, and what is the diagnosis?

Malignant Neoplasms of the Penis with Radiologic and Pathologic Correlation.

Penile malignancy is the third most common male-specific genitourinary malignancy, with squamous cell carcinoma representing the most common histologic type. Squamous cell carcinoma is an epithelial malignancy, frequently developing from the mucosal surfaces of the foreskin, glans, and coronal sulcus and manifesting as a distal infiltrative or ulcerated mass. This typically occurs in men from the 6th to 8th decades of life, and risk factors include human papillomavirus, phimosis, presence of foreskin and poor hygiene, chronic inflammatory conditions such as lichen sclerosus, trauma, and smoking.

Effect of Dataset Size and Medical Image Modality on Convolutional Neural Network Model Performance for Automated Segmentation: A CT and MR Renal Tumor Imaging Study.

The aim of this study is to investigate the use of an exponential-plateau model to determine the required training dataset size that yields the maximum medical image segmentation performance. CT and MR images of patients with renal tumors acquired between 1997 and 2017 were retrospectively collected from our nephrectomy registry. Modality-based datasets of 50, 100, 150, 200, 250, and 300 images were assembled to train models with an 80-20 training-validation split evaluated against 50 randomly held out test set images.

Clinical Implementation of an Artificial Intelligence Algorithm for Magnetic Resonance-Derived Measurement of Total Kidney Volume.

Objective: To evaluate the performance of an internally developed and previously validated artificial intelligence (AI) algorithm for magnetic resonance (MR)-derived total kidney volume (TKV) in autosomal dominant polycystic kidney disease (ADPKD) when implemented in clinical practice.

Patients And Methods: The study included adult patients with ADPKD seen by a nephrologist at our institution between November 2019 and January 2021 and undergoing an MR imaging examination as part of standard clinical care. Thirty-three nephrologists ordered MR imaging, requesting AI-based TKV calculation for 170 cases in these 161 unique patients.

Unplanned Conversion From Partial to Radical Nephrectomy: An Analysis of Incidence, Etiology, and Risk Factors.

Purpose: Conversions from partial to radical nephrectomy are uncommon and reports on this topic are rare. In this study we present a detailed analysis of conversions from partial to radical nephrectomy in a single-institutional contemporary experience and provide an analysis of preoperative risk factors.

Materials And Methods: Patients who underwent converted (cases) and completed (controls) partial nephrectomy from 2000 to 2015 were matched 1:1 for analysis.

Kidney Cysts in Hypophosphatemic Rickets With Hypercalciuria: A Case Series.

Rationale & Objective: Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is a rare monogenic disorder caused by pathogenic variants. HHRH is characterized by kidney phosphate wasting, hypophosphatemia, hypercalciuria, an elevated 1,25-dihydroxyvitamin D level, nephrocalcinosis, and urinary stone disease. Previously, we reported a 100% prevalence of kidney cysts in the related CYP24A1 deficiency.

Partial versus radical nephrectomy in clinical T2 renal masses.

Objective: To report perioperative, renal functional and oncologic outcomes for patients undergoing partial or radical nephrectomy for cT2 renal masses.

Methods: Retrospective review of patients who underwent partial (n = 72) or radical nephrectomy (n = 379) for cT2 renal masses from 2000 to 2016. After propensity adjustment using inverse probability weighting, the following were compared by surgery (partial or radical nephrectomy): complications, renal function measured by estimated glomerular filtration rate as continuous and as <60 mL/min/1.

High Prevalence of Kidney Cysts in Patients With CYP24A1 Deficiency.

Introduction: Loss-of-function variants in the gene cause a rare hereditary disease characterized by reduced 24-hydroxylase enzyme activity, increased serum 1,25-dihydroxycholecalciferol levels, hypercalcemia, hypercalciuria, and nephrocalcinosis and/or nephrolithiasis. Kidney cysts in patients with CYP24A1 deficiency were first reported in a single case study from our center. However, a possible association between CYP24A1 deficiency and kidney cysts has not been described.

Grading Chromophobe Renal Cell Carcinoma: Evidence for a Four-tiered Classification Incorporating Coagulative Tumor Necrosis.

Background: Although grading systems have been proposed for chromophobe renal cell carcinoma (ChRCC), including a three-tiered system by Paner et al (Paner GP, Amin MB, Alvarado-Cabrero I, et al. A novel tumor grading scheme for chromophobe renal cell carcinoma: prognostic utility and comparison with Fuhrman nuclear grade. Am J Surg Pathol 2010;34:1233-40), none have gained clinical acceptance, and the World Health Organization (WHO) currently recommends against grading ChRCC.

Hemosiderin deposition in papillary renal cell carcinoma and its potential to mask enhancement on MRI: analysis of 110 cases.

Objectives: To evaluate the relationship between imperceptible T1 enhancement of papillary renal cell carcinoma (pRCC) on MR and intratumoral hemosiderin deposition.

Methods: One hundred ten pRCCs (≤ 7 cm) were evaluated by MR with in- and opposed-phase spoiled gradient echo (GRE) and T1-weighted spoiled GRE with fat suppression before and after contrast. Hemosiderin deposition was assessed by SI and D on in- and opposed-phase images.

Timing and distribution of early renal cell carcinoma recurrences stratified by pathological nodal status in M0 patients at the time of nephrectomy.

Objectives: To evaluate the timing and distribution of first renal cell carcinoma metastasis after nephrectomy stratified by nodal status.

Methods: We evaluated patients treated with nephrectomy for sporadic, unilateral renal cell carcinoma between 1970 and 2011 who subsequently developed distant metastasis to three or fewer sites. Site-specific metastases-free 2-year survival rates were estimated using the Kaplan-Meier method.

Post-treatment prostate MRI.

Accurate early detection of recurrent prostate cancer after surgical or nonsurgical treatment is increasingly relevant in the era of evolving options for salvage therapy. The importance of differentiating between local tumor recurrence, distant metastatic disease, and a combination of both in a patient with biochemical recurrence of prostate cancer is essential for appropriate treatment selection. Magnetic resonance imaging (MRI) is the best test for localization and characterization of locally residual or recurrent prostate cancer.

Percutaneous Image-guided Core Needle Biopsy for Upper Tract Urothelial Carcinoma.

Objective: To better understand the safety and diagnostic yield of percutaneous core-needle biopsy (PCNB) for upper tract urothelial carcinoma (UTUC).

Methods: Of 444 patients undergoing radical nephroureterectomy (RNU) for UTUC between 2009 and 2017 at our institution, 42 who had PCNB prior to RNU were identified for analysis. Endpoints included safety, diagnostic yield, and concordance with RNU pathology.

Frequency of Bleeding Complications After Percutaneous Core Needle Biopsy and the Association With Aspirin Usage and Length of Aspirin Discontinuation.

The purpose of this study is to report the frequency of major bleeding after percutaneous image-guided core biopsy and its association with aspirin usage and duration of prebiopsy aspirin abstinence. A retrospective review of percutaneous image-guided core biopsies performed at our institution between September 1, 2005, and September 1, 2016, was performed ( = 30,966). Patients were excluded if aspirin usage data were missing ( = 633).

Percutaneous ureteral biopsy: safety and diagnostic yield.

Purpose: To evaluate safety and diagnostic yield of percutaneous CT-guided biopsy of extrarenal upper urinary tract lesions.

Materials And Methods: Retrospective review of our institutional database of image-guided biopsies yielded 44 CT-guided percutaneous biopsies in 44 unique patients that targeted ureteral (30, 68%) or other non-renal upper urinary tract lesions (14, 32%) between January 1, 2000 and May 1, 2017. Indications, pre-biopsy imaging, biopsy technique, peri-procedural antithrombotic use, complications including bleeding defined by Society of Interventional Radiology criteria, pathology results, and subsequent imaging were reviewed up to 3 months after the procedure to evaluate safety and diagnostic yield.

The Probability of Aggressive Versus Indolent Histology Based on Renal Tumor Size: Implications for Surveillance and Treatment.

Background: While the probability of malignant versus benign histology based on renal tumor size has been described, this alone does not sufficiently inform decision-making in the modern era since indolent malignant tumors can be managed with active surveillance.

Objective: To characterize the probability of aggressive versus indolent histology based on radiographic tumor size.

Design, Setting, And Participants: We evaluated patients who underwent radical or partial nephrectomy at Mayo Clinic for a pT1-2, pNx/0, M0 solid renal tumor between 1990 and 2010.

Bleeding Complications After Percutaneous Liver Biopsy: Do Subcapsular Lesions Pose a Higher Risk?

Objective: The purpose of this study is to determine the incidence of moderate and severe bleeding complications after subcapsular liver mass biopsy and compare it with the incidences of such complications after nonsubcapsular liver mass biopsy and after random biopsy.

Materials And Methods: This retrospective review of ultrasound-guided liver biopsies was performed between January 2006 and February 2015. Biopsy type, needle size, the number of needle passes, and mass size and depth were recorded.

Patient and nonradiographic tumor characteristics predicting lipid-poor angiomyolipoma in small renal masses: Introducing the BEARS index.

Purpose: To create a simple model using clinical variables for predicting lipid-poor angiomyolipoma (AML) in patients with small renal masses presumed to be renal cell carcinoma (RCC) from preoperative imaging.

Materials And Methods: A series of patients undergoing partial nephrectomy (PN) for renal masses ≤4 cm was identified using a prospectively maintained database. Patients were excluded if standard preoperative imaging was not consistent with RCC.

LI-RADS M (LR-M): definite or probable malignancy, not specific for hepatocellular carcinoma.

LI-RADS v2017 introduces major changes to the diagnostic criteria for LR-M observations to better guide radiologists in the use of this malignant category designation. LR-M is intended to preserve the specificity of the LI-RADS algorithm for diagnosis of HCC while not losing sensitivity for diagnosis of malignancy. The purpose of this paper is to provide a brief background on LR-M, discuss the diagnostic criteria new to v2017, special considerations for its application, and management implications.