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Background: Myosteatosis has been associated with shorter overall survival in cancer patients. The increase in ectopic fat might not be limited to skeletal muscle only and might also extend to other sites such as the liver, resulting in non‐alcoholic fatty liver disease (NAFLD). In this study, we assessed the relationship between myosteatosis and NAFLD and their association with overall survival in patients with colorectal liver metastases undergoing partial hepatectomy. Methods: Patients were selected from a prospective cohort of 289 consecutive patients with colorectal liver metastases. All patients with a preoperative computed tomography (CT)‐scan and liver biopsy obtained during surgery were included. If available a second pre‐operative CT scan was used to calculate changes in body composition over time. Muscle radiation attenuation was defined as the average Hounsfield units on CT of all muscle tissue at the L3 level. Liver biopsies were graded by a liver pathologist using the steatosis, activity, and fibrosis scoring system for NAFLD. Results: Two‐hundred and eighteen patients had an available liver biopsy of which 131 patients had two available pre‐operative CT scans with an average time interval of 3.2 months. One‐hundred and thirty‐five (62%) biopsies were classified as NAFLD. In multivariable Cox‐regression analysis, NAFLD [hazard ratio (HR): 1.8, 95%‐confidence interval (CI) 1.0–3.0, P = 0.037], increase in myosteatosis (HR 1.8, 95%‐CI 1.1–2.9, P = 0.018), and skeletal muscle loss (HR 1.7, 95%‐CI 1.0–2.9, P = 0.035) were independently associated with shorter overall survival while high visceral adipose tissue fat content was associated with longer overall survival (HR: 0.7, 95%‐CI 0.5–0.9, P = 0.014). Conclusions: Ectopic fat content of liver as well as skeletal muscle tissue is independently associated with shorter overall survival in patients with colorectal liver metastases, while increased visceral adipose tissue fat content is associated with longer overall survival. [ABSTRACT FROM AUTHOR]

Background: Pancreatic neuroendocrine tumors (pNETs) have a high prevalence in patients with multiple endocrine neoplasia type 1 (MEN1) and are the leading cause of death. Tumor size is still regarded as the main prognostic factor and therefore used for surgical decision-making. We assessed reliability and agreement of radiological and pathological tumor size in a population-based cohort of patients with MEN1-related pNETs. Methods: Patients were selected from the Dutch MEN1 database if they had undergone a resection for a pNET between 2003 and 2018. Radiological (MRI, CT, and endoscopic ultrasonography [EUS]) and pathological tumor size were collected from patient records. Measures of agreement (Bland-Altman plots with limits of agreement [LoA] and absolute agreement) and reliability (intraclass correlation coefficients [ICC] and unweighted kappa) were calculated for continuous and categorized (< or ≥2 cm) pNET size. Results: In 73 included patients, the median radiological and pathological tumor sizes measured were 22 (3–160) and 21 (4–200) mm, respectively. Mean bias between radiological and pathological tumor size was −0.2 mm and LoA ranged from −12.9 to 12.6 mm. For the subgroups of MRI, CT, and EUS, LoA of radiological and pathological tumor size ranged from −9.6 to 10.9, −15.9 to 15.8, and −13.9 to 11.0, respectively. ICCs for the overall cohort, MRI, CT, and EUS were 0.80, 0.86, 0.75, and 0.76, respectively. Based on the 2 cm criterion, agreement was 81.5%; hence, 12 patients (18.5%) were classified differently between imaging and pathology. Absolute agreement and kappa values of MRI, CT, and EUS were 88.6, 85.7, and 75.0%, and 0.77, 0.71, and 0.50, respectively. Conclusion: Within a population-based cohort, MEN1-related pNET size was not systematically over- or underestimated on preoperative imaging. Based on agreement and reliability measures, MRI is the preferred imaging modality. [ABSTRACT FROM AUTHOR]

Background Myosteatosis, characterized by inter- and intramyocellular fat deposition, is strongly related to poor overall survival after surgery for periampullary cancer. It is commonly assessed by calculating the muscle radiation attenuation on computed tomography (CT) scans. However, since magnetic resonance imaging (MRI) is replacing CT in routine diagnostic work-up, developing methods based on MRI is important. We developed a new method using MRI-muscle signal intensity to assess myosteatosis and compared it with CT-muscle radiation attenuation. Methods Patients were selected from a prospective cohort of 236 surgical patients with periampullary cancer. The MRI-muscle signal intensity and CT-muscle radiation attenuation were assessed at the level of the third lumbar vertebra and related to survival. Results Forty-seven patients were included in the study. Inter-observer variability for MRI assessment was low (R 2 = 0.94). MRI-muscle signal intensity was associated with short survival: median survival 9.8 (95%-CI: 1.5–18.1) vs. 18.2 (95%-CI: 10.7–25.8) months for high vs. low intensity, respectively (p = 0.038). Similar results were found for CT-muscle radiation attenuation (low vs. high radiation attenuation: 10.8 (95%-CI: 8.5–13.1) vs. 15.9 (95%-CI: 10.2–21.7) months, respectively; p = 0.046). MRI-signal intensity correlated negatively with CT-radiation attenuation ( r =−0.614, p < 0.001). Conclusions Myosteatosis may be adequately assessed using either MRI-muscle signal intensity or CT-muscle radiation attenuation. [ABSTRACT FROM AUTHOR]