Scurvy: an unusual complication of paediatric cancer treatment.

Scurvy is a disease that is rarely encountered in modern medicine. A condition that was classically associated with sailors, its incidence has decreased dramatically since the discovery of its association with vitamin C deficiency. We present the case of a 2-year-old boy, whose treatment for neuroblastoma was complicated by gastrointestinal disease, which necessitated enteral feeding. While still undergoing treatment, he started to complain about increasing pain in his lower limbs, which appeared to be markedly tender on palpation. Radiographic findings suggested a diagnosis of scurvy, which was subsequently confirmed on serum biochemistry. This was an unexpected finding, as the child had been receiving adequate vitamin C in his enteral feeds. However, his absorption had become severely impaired due to pseudomembranous gastritis and enteritis, leading to his deficient state. He significantly improved after intravenous ascorbic acid replacement and demonstrated a full recovery, both clinically and radiologically. This case highlights the importance of considering scurvy in the differential diagnosis for at-risk patients. Early recognition can facilitate the simple treatment of this potentially serious condition.

A Pictorial Review of Hepatobiliary Magnetic Resonance Imaging With Hepatocyte-Specific Contrast Agents: Uses, Findings, and Pitfalls of Gadoxetate Disodium and Gadobenate Dimeglumine.

Magnetic resonance imaging (MRI) has a well-established role as a highly specific and accurate modality for characterizing benign and malignant focal liver lesions. In particular, contrast-enhanced MRI using hepatocyte-specific contrast agents (HSCAs) improves lesion detection and characterization compared to other imaging modalities and MRI techniques. In this pictorial review, the mechanism of action of gadolinium-based MRI contrast agents, with a focus on HSCAs, is described. The clinical indications, protocols, and emerging uses of the 2 commercially available combined contrast agents available in the United States, gadoxetate disodium and gadobenate dimeglumine, are discussed. The MRI features of these agents are compared with examples of focal hepatic masses, many of which have been obtained within the same patient therefore allowing direct lesion comparison. Finally, the pitfalls in the use of combined contrast agents in liver MRI are highlighted.

Virtual monoenergetic reconstruction of contrast-enhanced dual energy CT at 70keV maximizes mural enhancement in acute small bowel obstruction.

PURPOSE: In patients with small bowel obstruction (SBO), it is challenging to detect early ischemia. The purpose of this study is to evaluate the quantitative and qualitative benefits of virtual monoenergetic image (VMI) reconstruction in the assessment of small bowel mural enhancement on dual source dual energy computed tomography (CT) scans of the abdomen. MATERIALS AND METHODS: Institutional review board approval was obtained, for this retrospective analysis. 72 consecutive patients with acute SBO were scanned using a second generation 128-slice dual source, CT system. Images were reconstructed at VMI energy levels from 40 to 110keV in 10keV increments and were analysed quantitatively and qualitatively. Contrast to noise ratios (CNR) and signal to noise ratios (SNR) for mural enhancement were recorded for all VMI datasets and compared to conventional polychromatic images (PCI) at 120kVp. Subjective analysis of mural enhancement on VMI and PCI was performed by 3 blinded readers. RESULTS: Optimal CNR values for small intestinal mural enhancement were observed at 70keV. Qualitative assessment revealed that there was no statistical difference in diagnostic accuracy between VMI and PCI. All readers reported improved confidence when assessing the contrast enhancement on the 70keV VMI dataset and in our series, 2 additional cases of ischemia were identified on this reconstruction. CONCLUSION: Contrast-enhanced dual source dual energy CT with VMI reconstruction at 70keV maximizes the CNR of small bowel mural enhancement and increases the overall diagnostic confidence in assessing mural enhancement in patients with SBO.

Multiparametric magnetic resonance imaging-targeted biopsy for the detection of prostate cancer in patients with prior negative biopsy results.

PURPOSE: We aimed to determine the performance of multiparametric magnetic resonance imaging (mpMRI) in the detection of prostate cancer (PCa) in patients with prior negative transrectal ultrasound-guided prostate biopsy (TRUS-B) results. MATERIALS AND METHODS: Between 2010 and 2013, 2,416 men underwent TRUS-B or an mpMRI or both at Vancouver General Hospital. Among these, 283 men had persistent suspicion of PCa despite prior negative TRUS-B finding. An MRI was obtained in 112, and a lesion (prostate imaging reporting and data system score ≥ 3) was identified in 88 cases (78%). A subsequent combined MRI-targeted and standard template biopsy was performed in 86 cases. A matching cohort of 86 patients was selected using a one-nearest neighbor method without replacement. The end points were the rate of diagnosis of PCa and significant PCa (sPCa) (Gleason > 6, or > 2 cores, or > 50% of any core). RESULTS: MRI-targeted TRUS-B detected PCa and sPCa in 36 (41.9%) and 30 (34.9%) men when compared with 19 (22.1%) and 14 (16.3%), respectively, men without mpMRI (P = 0.005 for both). In 9 cases (10.4%), MRI-targeted TRUS-B detected sPCa that was missed on standard cores. sPCa was present in 6 cases (6.9%) on standard cores but not the targeted cores. Multivariate analysis revealed that prostate imaging reporting and data system score and prostate-specific antigen density > 0.15 ng/ml(2) were statistically significant predictors of significant cancer detection (odds ratio = 14.93, P < 0.001 and odds ratio = 6.19, P = 0.02, respectively). CONCLUSION: In patients with prior negative TRUS-B finding, MRI-targeted TRUS-B improves the detection rate of all PCa and sPCa.

Multiparametric magnetic resonance imaging enhances detection of significant tumor in patients on active surveillance for prostate cancer.

OBJECTIVE: To determine whether multiparametric magnetic resonance imaging (MRI) of the prostate (mpMRI) combined with MRI fusion technology during transrectal ultrasound-guided biopsy can enhance the detection of significant disease in patients with apparent low-risk prostate cancer on active surveillance (AS). MATERIALS AND METHODS: We reviewed the charts of 603 patients on AS for localized prostate cancer between January 2006 and September 2013. mpMRI before repeat transrectal ultrasound-guided biopsy was obtained in 111 patients, of whom 69 underwent subsequent fusion biopsy (39 true and 30 cognitive) in addition to standard template biopsy. The results of fusion biopsy were compared with the standard biopsy. The primary endpoint was termination of AS. RESULTS: mpMRI detected 118 suspicious lesions in 70 patients (63%). Of these, 42 patients (60%) had lesions with Prostate imaging, reporting, and data system (PIRADS) score 3, and 28 patients (40%) had PIRADS score 4 or 5 lesions. AS was terminated in 27 (24.3%) of the 111 patients who underwent mpMRI. Seventeen patients stopped AS based on mpMRI findings including 16 for pathologic progression in target biopsies and 1 for lesion size increase, whereas the other 10 stopped AS because of pathologic progression in the standard cores (n = 6) or other reasons (n = 4). Use of mpMRI increased the rate of AS termination (27 vs. 10; P = .002). On multivariate analysis, PIRADS score 4-5 (vs. 3) was the only significant predictor of AS termination (P = .015). CONCLUSION: These preliminary retrospective findings suggest that mpMRI with subsequent fusion biopsy enhances the identification of AS patients requiring definitive treatment.