Nicolas De Vos

Clinical Value of 18F-FDG- PET-CT in the Preoperative Staging of Peritoneal Carcinomatosis from Colorectal Origin

Abstract Background : Adequate staging is essential in patients with peritoneal carcinomatosis (PC) from colorectal cancer (CRC) who are candidates for cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC). Metabolic imaging using 18F-FDG-PET-CT is commonly used to exclude distant metastasis in these patients. Here, we aimed to assess the performance of 18F-FDG-PET-CT in locoregional staging of the extent of PC. Methods : Patients with PC from CRC underwent staging including 18F-FDG-PET-CT. In the absence of systemic dissemination, CRS and oxaliplatin based HIPEC were performed. The extent of PC was quantified during surgery using the modified 7 region count (7RC). The correlation between imaging based estimation of PC extent and surgical 7RC was analyzed using Pearson correlation using both patient based and region based analyses. Results : Fifty-five patients were included between February 2005 and October 2018. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 57%, 98%, 95%, 78% and 82% respectively for non-mucinous tumors and 32%, 100%, 100%, 55% and 63% respectively. 18F-FDG-PET-CT detected the presence of colorectal PC in 96% of patients suffering from PC with nonmucinous histology and in 60% of patients suffering from PC with mucinous histology. Correlation between imaging 7RC and surgical 7RC was better for PC with nonmucinous histology (r = 0.623) than for PC with mucinous histology (r = -0.180). Conclusions : Despite of underestimating the exact extent of disease involvement, 18F-FDG-PET-CT shows good performance in detecting colorectal PC with nonmucinous histology. For colorectal PC with mucinous histology, 18F-FDG- PET-CT, however, shows poor performance. Since 18F-FDG-PET-CT did not detect the presence of colorectal PC in all patients in whom long-term survival could be achieved, 18F-FDG-PET-CT should be implemented into a broad preoperative assessment strategy.

Common Mistakes and Pitfalls in Magnetic Resonance Imaging of the Knee

This pictorial review presents an overview of common interpretation errors and pitfalls in magnetic resonance imaging (MRI) of the knee. Instead of being exhaustive, we will emphasize those pitfalls that are most commonly encountered by young residents or less experienced radiologists.

Nerve Sheath Tumors

Nerve sheath tumors are a distinct type of soft tissue tumors. The updated WHO classification of nerve sheath tumors includes several new benign and malignant nerve sheath tumor types. Imaging features suggestive for nerve sheath tumors include location near a nerve, fusiform shape, tail sign, split-fat sign, target sign, fascicular sign, and degenerative muscle changes.

Dysbaric osteonecrosis of the humerus

1. W. Dega Orthopaedic and Rehabilitation University Hospital, Karol Marcinkowski University of Medical Sciences; Poznan, Poland 2. Ghent University Hospital, Department of Radiology; De Pintelaan 185, 9000 Ghent, Belgium 3. AZ Sint-Maarten Duffel-Mechelen, Department of Radiology; Leopoldstraat 2, 2800 Mechelen, Belgium 4: University Hospital Antwerp, Department of Radiology; Wilrijkstraat 10, 2650 Antwerp, Belgium; Email:filip.vanhoenacker@telenet.be University Hospital Antwerp