Span of spleen is associated with disability status in multiple sclerosis: a cross-sectional abdominopelvic ultrasonography study.

Characteristics of livers and spleens of people with multiple sclerosis (pwMS) could constitute good biomarkers of MS-related characteristics such as the disability status. To test the hypothesis "the gross anatomical features of livers and spleens, are not similar between pwMS with different disease characteristics" a cross-sectional study was conducted on pwMS seen at the Isfahan MS clinic, Iran, from February until December 2023. Definitive, otherwise-healthy, pwMS were enrolled after an initial laboratory evaluation. Presence/absence and grading of non-alcoholic fatty liver disease (NAFLD) and the span of spleen were determined by a radiologist using high-resolution abdominopelvic ultrasonography. 193 pwMS (160 women) were enrolled. Of whom, 143 (74.1%) were receiving first-line disease-modifying therapies (DMTs), 24 (12.4%) fingolimod, and 26 (13.5%) rituximab. The span of spleen was negatively associated with EDSS (adjusted ß [SE] - 4.08 [1.52], p < 0.01), as well as 6 m-CDW (adjusted ß [SE] - 6.94 [3.56], p = 0.05), unlike age, DMTs, and MS duration (all with p > 0.05). Receiver operating characteristic analysis showed, spleen span performs significant but poor in discrimination of EDSS > 1 from EDSS = 1 (area under curve [AUC] 0.62, SE 0.05, p < 0.01), yet, significant and fair in discrimination of presence from absence of 6 m-CDW (AUC 0.72, SE 0.06, p < 0.01). Other findings were unremarkable. Further longitudinal, prospective studies are warranted to confirm whether smaller spleens are predictive of higher disability accrual rate in pwMS. Particularly, findings require further validation in untreated/treatment-naïve pwMS, and ones with higher EDSS scores.

Comparative analysis of F-18 FDG PET/CT images between scrub typhus and systemic lupus erythematosus.

This study evaluated the use of F-18 fluorodeoxyglucose (FDG) PET/CT imaging to differentiate between scrub typhus and systemic lupus erythematosus (SLE) in patients presenting with lymphadenopathy. We carried out a retrospective analysis of 18 scrub typhus patients and seven SLE patients, using various imaging parameters, including lymph node size, spleen and liver lengths, the distance between the two farthest lesions (Dmax), and assessments of glucose metabolism. On FDG PET images, we measured the maximum standardized uptake value (SUVmax) of the lymph nodes, spleen, and liver and the mean standardized uptake value (SUVmean) of the liver and spleen. The Dmax values of scrub typhus patients were significantly longer than those of SLE patients, indicating that lymphadenopathy is more generalized in the patients with scrub typhus. The SUVmax values for the lymph node, spleen, and liver were also higher in patients with scrub typhus, while the SUVmean of the liver and spleen did not differ between the two groups. This study is the first to compare FDG PET/CT images between these two conditions, suggesting the potential of this imaging modality to provide critical diagnostic distinctions.

Healthy tissue metabolism assessed by [18F]FDG PET/CT as a marker of prognosis and adverse events in advanced Hodgkin lymphoma patients.

The aim of the study was to assess healthy tissue metabolism (HTM) using 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) during chemotherapy in Hodgkin lymphoma (HL) and the association of HTM with baseline metabolic tumour volume (MTV), haematological parameters, adverse events (AEs), early response and progression-free survival (PFS). We retrospectively identified 200 patients with advanced HL from the RATHL trial with [18F]FDG-PET/CT before (PET0) and following 2 cycles of chemotherapy (PET2). [18F]FDG-uptake was measured in bone marrow (BM), spleen, liver and mediastinal blood pool (MBP). Deauville score (DS) 1-3 was used to classify responders and DS 4-5, non-responders. [18F]FDG-uptake decreased significantly in BM and spleen and increased in liver and MBP at PET2 (all p < 0.0001), but was not associated with MTV. Higher BM uptake at PET0 was associated with lower baseline haemoglobin and higher absolute neutrophil counts, platelets, and white blood cells. High BM, spleen, and liver uptake at PET0 was associated with neutropenia after cycles 1-2. BM uptake at PET0 was associated with treatment failure at PET2 and non-responders with higher BM uptake at PET2 had significantly inferior PFS (p = 0.023; hazard ratio = 2.31). Based on these results, we concluded that the change in HTM during chemotherapy was most likely a direct impact of chemotherapy rather than a change in MTV. BM uptake has prognostic value in HL.

Central obesity and fat-free mass are associated with a larger spleen volume in the general population.

Background and aim: As the spleen plays a significant role in immunity, the aim was to investigate the associations of different body composition markers derived from various sources with spleen volume in a general population sample. Materials and methods: Cross-sectional data of 1095 individuals (570 women; 52%) aged between 30 and 90 years were collected in the Study of Health in Pomerania (SHIP-START-2). We measured spleen volume by magnetic resonance imaging (MRI).Body composition markers were derived from classic anthropometry, bioelectrical impedance analysis, including absolute fat mass (FM) and fat-free mass (FFM), as well as from MRI, including visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and liver fat content. Sex-stratified-adjusted linear regression models were used to analyze the associations of body composition markers with spleen volumes. Results: We observed positive associations of body mass index, body weight, waist circumference, hip circumference, waist-to-height ratio, absolute FM, absolute FFM, and VAT and SAT with spleen volume in men and women. An 8.12 kg higher absolute FFM was associated with a 38.4 mL (95% confidence interval [CI]: 26.7-50.1) higher spleen volume in men and a 5.21 kg higher absolute FFM with a 42.6 mL (95% CI: 26.2-59.0) higher spleen volume in women. Conclusion: Our findings indicate that obesity-related body composition markers and FFM are associated with a higher spleen volume. Particularly, higher absolute FFM showed a strong association with a larger spleen volume in both men and women. Further studies are warranted to understand the clinical significance of body composition markers on large spleen volume.

Wandering spleen presenting in the form of right sided pelvic mass and pain in a patient with AD-PCKD: a case report and review of the literature.

BACKGROUND: Wandering spleen is a rare clinical entity in which the spleen is hypermobile and migrate from its normal left hypochondriac position to any other abdominal or pelvic position as a result of absent or abnormal laxity of the suspensory ligaments (Puranik in Gastroenterol Rep 5:241, 2015, Evangelos in Am J Case Rep. 21, 2020) which in turn is due to either congenital laxity or precipitated by trauma, pregnancy, or connective tissue disorder (Puranik in Gastroenterol Rep 5:241, 2015, Jawad in Cureus 15, 2023). It may be asymptomatic and accidentally discovered for imaging done for other reasons or cause symptoms as a result of torsion of its pedicle and infarction or compression on adjacent viscera on its new position. It needs to be surgically treated upon discovery either by splenopexy or splectomy based on whether the spleen is mobile or not. CASE PRESENTATION: We present a case of 39 years old female Ethiopian patient who presented to us complaining constant lower abdominal pain especially on the right side associated with swelling of one year which got worse over the preceding few months of her presentation to our facility. She is primiparous with delivery by C/section and a known case of HIV infection on HAART. Physical examination revealed a right lower quadrant well defined, fairly mobile and slightly tender swelling. Hematologic investigations are unremarkable. Imaging with abdominopelvic U/S and CT-scan showed a predominantly cystic, hypo attenuating right sided pelvic mass with narrow elongated attachment to pancreatic tail and absent spleen in its normal position. CT also showed multiple different sized purely cystic lesions all over both kidneys and the pancreas compatible with AD polycystic kidney and pancreatic disease. With a diagnosis of wandering possibly infarcted spleen, she underwent laparotomy, the finding being a fully infarcted spleen located on the right half of the upper pelvis with twisted pedicle and dense adhesions to the adjacent distal ileum and colon. Release of adhesions and splenectomy was done. Her post-operative course was uneventful. CONCLUSION: Wandering spleen is a rare clinical condition that needs to be included in the list of differential diagnosis in patients presenting with lower abdominal and pelvic masses. As we have learnt from our case, a high index of suspicion is required to detect it early and intervene by doing splenopexy and thereby avoiding splenectomy and its related complications.

Validation of Baveno VII criteria for clinically significant portal hypertension by two-dimensional shear wave elastography.

BACKGROUND: The Baveno VII consensus proposed criteria for the non-invasively diagnosis of clinically significant portal hypertension (CSPH) in patients with compensated advanced chronic liver disease (cACLD). The performance of Baveno VII criteria for assessing CSPH by two-dimensional shear wave elastography (2D-SWE) had not been well validated. We aimed to validate the performance of Baveno VII criteria for rule-in and rule-out CSPH by 2D-SWE. METHOD: This is an international multicenter study including cACLD patients from China and Croatia with paired liver stiffness measurement (LSM), spleen stiffness measurement (SSM) by 2D-SWE, and hepatic venous pressure gradient (HVPG) were included. CSPH was defined as HVPG ≥ 10 mmHg. RESULT: A total of 146 patients with cACLD were enrolled, and finally 118 patients were included in the analysis. Among them, CSPH was documented in 79 (66.9%) patients. Applying the Baveno VII criteria for rule-out CSPH by 2D-SWE, [LSM ≤ 15 kPa and platelet count ≥ 150 × 109/L] OR SSM < 21 kPa, could exclude CSPH with sensitivity > 90% (93.5 or 98.7%) but negative predictive value < 90% (74.1 or 85.7%). Using the Baveno VII criteria for rule-in CSPH by 2D-SWE, LSM ≥ 25 kPa OR SSM ≥ 50 kPa, could diagnose CSPH with 100% specificity and 100% positive predictive values. CONCLUSION: Baveno VII criteria by 2D-SWE showed a good diagnostic performance for ruling in but not for ruling out CSPH, which might become an emerging non-invasive elastography tool to select the patients who needed non-selective beta blocker therapy.

Can thoraco-abdominal organ boundaries be accurately determined from X-ray and anthropometric surface scans? Implications for body armour system coverage and design.

To optimise soldier protection within body armour systems, knowledge of the boundaries of essential thoraco-abdominal organs is necessary to inform coverage requirements. However, existing methods of organ boundary identification are costly and time consuming, limiting widespread adoption for use on soldier populations. The aim of this study was to evaluate a novel method of using 3D organ models to identify essential organ boundaries from low dose planar X-rays and 3D external surface scans of the human torso. The results revealed that, while possible to reconstruct 3D organs using template 3D organ models placed over X-ray images, the boundary data (relating to the size and position of each organ) obtained from the reconstructed organs differed significantly from MRI organ data. The magnitude of difference varied between organs. The most accurate anatomical boundaries were the left, right, and inferior boundaries of the heart, and lateral boundaries for the liver and spleen. Visual inspection of the data demonstrated that 11 of 18 organ models were successfully integrated within the 3D space of the participant's surface scan. These results suggest that, if this method is further refined and evaluated, it has potential to be used as a tool for estimating body armour coverage requirements.

Imaging findings of Epstein-Barr Virus-positive inflammatory follicular dendritic cell sarcoma of spleen: A case report.

BACKGROUND: Spleen Epstein-Barr Virus (EBV)-positive inflammatory follicular dendritic cell sarcoma (FDCS) is rare, and the imaging signs are unclear. The COVID-19 has been confirmed to be the cause of pneumonia and can cause a variety of diseases including myocarditis. However, it has not been reported to be the cause of the exacerbation or activation of EBV-positive inflammatory FDCS. OBJECTIVE: The objective is to extract the imaging features of EBV-positive inflammatory FDCS in the spleen and analyze the reasons for the special features of this case. METHODS: By analyzing the patient's treatment process and imaging examinations (A 77-year-old female was admitted to the hospital due to generalized discomfort and pain symptoms. When she was admitted to the hospital a year earlier with COVID-19 pneumonia, a chest CT scan showed that she had a splenic tumor. During this admission, CT scans showed two irregularly shaped and unevenly dense soft tissue density masses within the spleen, with uneven enhancement on contrast-enhanced im-aging within the solid components and along the edges. PET/CT scans revealed elevated glucose metabolism in the masses. Postoperative pathological diagnosis confirmed splenic EBV-positive inflammatory FDCS.), reading the literature, sorting out the disease cognitive process, epidemiology, and pathological data of EBV-positive inflammatory FDCS, we discussed the imaging manifestations and possible differential diagnosis of the disease. RESULTS: The patient was finally diagnosed with splenic EBV-positive inflammatory FDCS. CONCLUSIONS: Imaging features of EBV-positive inflammatory FDCS in the spleen include a high incidence of hemorrhage and necrosis, persistent moderate enhancement of the solid portion, a "capsular-like enhancement" structure at the tumor edge, and possibly active glucose metabolism with high Standardized Uptake Values (SUVs). COVID-19 infection and long-term COVID-19 sequelae may exacerbate and activate EBV-positive inflammatory FDCS in the spleen, and the mechanism remains to be further studied.

[The 506th case: fever of unknown origin, negative PET-CT and hemoperitoneum].

A 48-year-old male was admitted to Peking Union Medical College Hospital presented with intermittent fever for two years. The maximum body temperature was 39 ℃, and could spontaneously relieve. The efficacy of antibacterial treatment was poor. He had no other symptoms and positive signs. He had a significant weight loss, and the serum lactate dehydrogenase increased significantly. It was highly alert to be lymphoma, but bone marrow smear and pathology, and PET-CT had not shown obvious abnormalities. Considering high inflammatory indicators, increased ferritin and large spleen, the patient had high inflammatory status, and was treated with methylprednisolone. Then the patient's body temperature was normal, but the platelet decreased to 33×109/L. During hospitalization, he had suddenly hemoperitoneum and hemorrhagic shock. He was found spontaneous spleen rupture without obvious triggers, and underwent emergency splenectomy. The pathological diagnosis of spleen was diffuse large B-cell lymphoma.

Metabolic-associated fatty liver voxel-based quantification on CT images using a contrast adapted automatic tool.

BACKGROUND & AIMS: Metabolic-dysfunction associated fatty liver disease (MAFLD) is highly prevalent and can lead to liver complications and comorbidities, with non-invasive tests such as vibration-controlled transient elastography (VCTE) and invasive liver biopsies being used for diagnosis The aim of the present study was to develop a new fully automatized method for quantifying the percentage of fat in the liver based on a voxel analysis on computed tomography (CT) images to solve previously unconcluded diagnostic deficiencies either in contrast (CE) or non-contrast enhanced (NCE) assessments. METHODS: Liver and spleen were segmented using nn-UNet on CE- and NCE-CT images. Radiodensity values were obtained for both organs for defining the key benchmarks for fatty liver assessment: liver mean, liver-to-spleen ratio, liver-spleen difference, and their average. VCTE was used for validation. A classification task method was developed for detection of suitable patients to fulfill maximum reproducibility across cohorts and highlight subjects with other potential radiodensity-related diseases. RESULTS: Best accuracy was attained using the average of all proposed benchmarks being the liver-to-spleen ratio highly useful for CE and the liver-to-spleen difference for NCE. The proposed whole-organ automatic segmentation displayed superior potential when compared to the typically used manual region-of-interest drawing as it allows to accurately obtain the percent of fat in liver, among other improvements. Atypical patients were successfully stratified through a function based on biochemical data. CONCLUSIONS: The developed method tackles the current drawbacks including biopsy invasiveness, and CT-related weaknesses such as lack of automaticity, dependency on contrast agent, no quantification of the percentage of fat in liver, and limited information on region-to-organ affectation. We propose this tool as an alternative for individualized MAFLD evaluation by an early detection of abnormal CT patterns based in radiodensity whilst abording detection of non-suitable patients to avoid unnecessary exposure to CT radiation. Furthermore, this work presents a surrogate aid for assessing fatty liver at a primary assessment of MAFLD using elastography data.

Non-Invasive Diagnostic Tests for Portal Hypertension in Patients with HBV- and HCV-Related Cirrhosis: A Comprehensive Review.

Clinically significant portal hypertension (CSPH) in patients with compensated advanced chronic liver disease indicates an increased risk of decompensation and death. While invasive methods like hepatic venous-portal gradient measurement is considered the gold standard, non-invasive tests (NITs) have emerged as valuable tools for diagnosing and monitoring CSPH. This review comprehensively explores non-invasive diagnostic modalities for portal hypertension, focusing on NITs in the setting of hepatitis B and hepatitis C virus-related cirrhosis. Biochemical-based NITs can be represented by single serum biomarkers (e.g., platelet count) or by composite scores that combine different serum biomarkers with each other or with demographic characteristics (e.g., FIB-4). On the other hand, liver stiffness measurement and spleen stiffness measurement can be assessed using a variety of elastography techniques, and they can be used alone, in combination with, or as a second step after biochemical-based NITs. The incorporation of liver and spleen stiffness measurements, alone or combined with platelet count, into established and validated criteria, such as Baveno VI or Baveno VII criteria, provides useful tools for the prediction of CSPH and for ruling out high-risk varices, potentially avoiding invasive tests like upper endoscopy. Moreover, they have also been shown to be able to predict liver-related events (e.g., the occurrence of hepatic decompensation). When transient elastography is not available or not feasible, biochemical-based NITs (e.g., RESIST criteria, that are based on the combination of platelet count and albumin levels) are valid alternatives for predicting high-risk varices both in patients with untreated viral aetiology and after sustained virological response. Ongoing research should explore novel biomarkers and novel elastography techniques, but current evidence supports the utility of routine blood tests, LSM, and SSM as effective surrogates in diagnosing and staging portal hypertension and predicting patient outcomes.

Splenic Pseudoprogression After CAR-T Therapy Detected by 18 F-FDG PET/CT in a Refractory Diffuse Large B-Cell Lymphoma Patient.

ABSTRACT: A 43-year-old woman diagnosed with refractory diffuse large B-cell lymphoma was referred to chimeric antigen receptor T-cell therapy at our institution. After 3 cycles of bridging therapy, preinfusion 18 F-FDG PET/CT suggested a complete metabolic response. 18 F-FDG PET/CT 1 month after chimeric antigen receptor T-cell infusion showed 2 foci of elevated activity in the spleen, which was finally confirmed as pseudoprogression.

Relation between resting spleen volume and apnea-induced increases in hemoglobin mass.

Introduction: Indigenous populations renowned for apneic diving have comparatively large spleen volumes. It has been proposed that a larger spleen translates to heightened apnea-induced splenic contraction and elevations in circulating hemoglobin mass (Hbmass), which, in theory, improves O2 carrying and/or CO2/pH buffering capacities. However, the relation between resting spleen volume and apnea- induced increases in Hbmass is unknown. Therefore, we tested the hypothesis that resting spleen volume is positively related to apnea-induced increases in total Hbmass. Methods: Fourteen healthy adults (six women; 29 ± 5 years) completed a two-minute carbon monoxide rebreathe procedure to measure pre-apneas Hbmass and blood volume. Spleen length, width, and thickness were measured pre-and post-five maximal apneas via ultrasound. Spleen volume was calculated via the Pilström equation (test-retest CV:2 ± 2%). Hemoglobin concentration ([Hb]; g/dl) and hematocrit (%) were measured pre- and post-apneas via capillary blood samples. Post-apneas Hbmass was estimated as post-apnea [Hb] x pre-apnea blood volume. Data are presented as mean ± SD. Results: Spleen volume decreased from pre- (247 ± 95 mL) to post- (200 ± 82 mL, p<0.01) apneas. [Hb] (14.6 ± 1.2 vs. 14.9 ± 1.2 g/dL, p<0.01), hematocrit (44 ± 3 vs. 45 ± 3%, p=0.04), and Hbmass (1025 ± 322 vs. 1046 ± 339 g, p=0.03) increased from pre- to post-apneas. Pre-apneas spleen volume was unrelated to post-apneas increases in Hbmass (r=-0.02, p=0.47). O2 (+28 ± 31 mL, p<0.01) and CO2 (+31 ± 35 mL, p<0.01) carrying capacities increased post-apneas. Conclusion: Larger spleen volume is not associated with a greater rise in apneas-induced increases in Hbmass in non-apnea-trained healthy adults.

Correlation between spleen density and prognostic outcomes in patients with colorectal cancer after curative resection.

OBJECTIVE: The objective of this study was to investigate the correlation between spleen density and the prognostic outcomes of patients who underwent curative resection for colorectal cancer (CRC). METHODS: The clinical data of patients who were diagnosed with CRC and underwent radical resection were retrospectively analyzed. Spleen density was determined using computed tomography. Analysis of spleen density in relation to overall survival (OS) and disease-free survival (DFS) utilizing the Kaplan-Meier method. Univariate and multivariate Cox regression models were used to screen for independent prognostic factors, and a nomogram was constructed to predict OS and DFS. Moreover, internally validated using a bootstrap resamplling method. RESULTS: Two hundred twelve patients were included, of whom 23 (10.85%) were defined as having a diffuse reduction of spleen density (DROSD) based on diagnostic cutoff values (spleen density≦37.00HU). Kaplan-Meier analysis indicated that patients with DROSD had worse OS and DFS than those non-DROSD (P < 0.05). Multivariate Cox regression analysis revealed that DROSD, carbohydrate antigen 199 (CA199) > 37 U/mL, tumor node metastasis (TNM) stage III-IV, laparoscopy-assisted operation and American Society of Anesthesiology (ASA) score were independent risk factors for 3-year DFS. DROSD, CA199 > 37 U/mL, TNM stage III-IV, hypoalbuminemia, laparoscopy-assisted operation and ASA score were chosen as predictors of for 3-year OS. Nomograms showed satisfactory accuracy in predicting OS and DFS using calibration curves, decision curve analysis and bootstrap resamplling method. CONCLUSION: Patients with DROSD who underwent curative resection have worse 3-year DFS and OS. The nomogram demonstrated good performance, particularly in predicting 3-year DFS with a net clinical benefit superior to well-established risk calculator.

Interrelationships Among Accumulations of Intra- and Periorgan Fats, Visceral Fat, and Subcutaneous Fat.

We aimed to clarify the relationship between intra- and periorgan fats, visceral fat, and subcutaneous fat. We used abdominal computed tomography to evaluate intra- and periorgan fat accumulations in the pancreas, liver, spleen, renal parenchyma, renal sinus, and skeletal muscle. The relationships between these fats, visceral fat, and subcutaneous fat were examined by using partial correlation and covariance analysis, adjusting for BMI. We found that visceral fat and all intra- and periorgan fat accumulations were positively correlated, whereas subcutaneous fat and accumulations of all intra- and periorgan fats and visceral fat were negatively correlated. Individuals with excessive visceral fat accumulation had significantly greater accumulations of fat in the pancreas, liver, renal sinus, and skeletal muscle than those without excessive visceral fat accumulation (P = 0.01, 0.006, 0.008, and 0.02, respectively). In conclusion, all intra- and periorgan fat accumulations show a positive correlation with visceral fat and a negative correlation with subcutaneous fat, independent of BMI.

Evaluation of spleen stiffness by 2D shear wave elastography for ruling out high risk varices in patients with chronic advanced liver disease. A systematic review and meta-analysis.

OBJECTIVES: To systematically review the accuracy of spleen stiffness measurement (SSM) by 2D- Shear Wave Elastography (2D-SWE) in predicting high risk for bleeding varices (HRV) in cirrhotic patients. METHODS: PubMed, Embase, Web of Science, Medline, Cochrane, and Google Scholar databases were searched up to 31/05/2023 for all human studies using 2D-SWE to estimate SSM and endoscopy to detect HRV. Meta-analysis was performed using a generalized linear mixed model. Publication bias was evaluated using the funnel plot asymmetry test. The Area Under the Summarized Receiver Operating Characteristic curve (AUSROC) was estimated using the "mada" package. RESULTS: A total of 13 studies and 1970 patients were included. Of them, 27.8 % had HRV. The pooled sensitivity and polled specificity of SSM in detecting HRV were 90 % (95 %CI:87-92 %) and 68 % (95 %CI:58-77 %), respectively, with an AUSROC at 0.86 (95 %CI:0.82-0.90). The median cutoff value of SSM in detecting HRV was 34.2 kPa. In studies including exclusively HBV cirrhotic patients, SSM's polled sensitivity and specificity in predicting HRV was 88 % (95 %CI:82-92 %) and 73 % (95 %CI:68-78 %), respectively. The AUSROC was 0.84 (95 %CI:0.81-0.87). The number of repeated measurements per patient (<5 or ≥ 5) did not affect the method's capability. Using Aixplorer to evaluate SSM had a higher sensitivity in ruling out HRV than other 2D-SWE devices. CONCLUSIONS: Our meta-analysis supports that SSM by 2D-SWE has a good diagnostic performance for ruling out HRV in cirrhosis.

Robustness of radiomic features in healthy abdominal parenchyma of patients with repeated examinations on dual-layer dual-energy CT.

OBJECTIVES: Robustness of radiomic features in physiological tissue is an important prerequisite for quantitative analysis of tumor biology and response assessment. In contrast to previous studies which focused on different tumors with mostly short scan-re-scan intervals, this study aimed to evaluate the robustness of radiomic features in cancer-free patients and over a clinically encountered inter-scan interval. MATERIALS AND METHODS: Patients without visible tumor burden who underwent at least two portal-venous phase dual energy CT examinations of the abdomen between May 2016 and January 2020 were included, while macroscopic tumor burden was excluded based upon follow-up imaging for all patients (≥3 months). Further, patients were excluded if no follow-up imaging was available, or if the CT protocol showed deviations between repeated examinations. Circular regions of interest were placed and proofread by two board-certified radiologists (4 years and 5 years experience) within the liver (segments 3 and 6), the psoas muscle (left and right), the pancreatic head, and the spleen to obtain radiomic features from normal-appearing organ parenchyma using PyRadiomics. Radiomic feature robustness was tested using the concordance correlation coefficient with a threshold of 0.75 considered indicative for deeming a feature robust. RESULTS: In total, 160 patients with 480 repeated abdominal CT examinations (range: 2-4 per patient) were retrospectively included in this single-center, IRB-approved study. Considering all organs and feature categories, only 4.58 % (25/546) of all features were robust with the highest rate being found in the first order feature category (20.37 %, 22/108). Other feature categories (grey level co-occurrence matrix, grey level dependence matrix, grey level run length matrix, grey level size zone matrix, and neighborhood gray-tone difference matrix) yielded an overall low percentage of robust features (range: 0.00 %-1.19 %). A subgroup analysis revealed the reconstructed field of view and the X-ray tube current as determinants of feature robustness (significant differences in subgroups for all organs, p < 0.001) as well as the size of the region of interest (no significant difference for the pancreatic head with p = 0.135, significant difference with p < 0.001 for all other organs). CONCLUSION: Radiomic feature robustness obtained from cancer-free subjects with repeated examinations using a consistent protocol and CT scanner was limited, with first order features yielding the highest proportion of robust features.