[68Ga]Ga-FAPI PET for the evaluation of digestive system tumors: systematic review and meta-analysis.

PURPOSE: Digestive system tumors are a group of tumors with high incidence in the world nowadays. The assessment of digestive system tumor metastasis by conventional imaging seems to be unsatisfactory. [68Ga]Ga-FAPI, which has emerged in recent years, seems to be able to evaluate digestive system tumor metastasis. We aimed to summarize the current evidence of [68Ga]Ga-FAPI PET/CT or PET/MR for the assessment of primary tumors, lymph node metastases, and distant metastases in digestive system tumors. Besides, we also aimed to perform a meta-analysis of the sensitivity of [68Ga]Ga-FAPI PET diagnosis to discriminate between digestive system tumors, primary lesions, and non-primary lesions (lymph node metastases and distant metastases). MATERIALS AND METHODS: PubMed, MEDLINE and Cochrane Library databases were searched from the beginning of the database build to August 12, 2022. All studies undergoing [68Ga]Ga-FAPI PET for the evaluation of digestive tumors were included in the screening and review. Screening and full text review was performed by 3 investigators and data extraction was performed by 2 investigators. Risk of bias was examined with the QUADAS-2 criteria. Diagnostic test meta-analysis was performed with a random-effects model. RESULTS: A total of 541 studies were retrieved. Finally, 22 studies were selected for the systematic review and 18 studies were included in the meta-analysis. In the 18 publications, a total of 524 patients with digestive system tumors, 459 primary tumor lesions of digestive system tumors, and 1921 metastatic lesions of digestive system tumors were included in the meta-analysis. Based on patients, the sensitivity of [68Ga]Ga-FAPI PET for the diagnosis of digestive system tumors was 0.98 (95% CI: 0.94-0.99). Based on lesions, the sensitivity of [68Ga]Ga-FAPI PET for the diagnostic evaluation of primary tumor lesions of the digestive system was 0.97 (95% CI: 0.93-0.99); the sensitivity of [68Ga]Ga-FAPI PET for the diagnostic evaluation of non-primary lesions (lymph node metastases and distant metastases) of the digestive system tumors was 0.94 (95% CI: 0.79-0.99). CONCLUSION: [68Ga]Ga-FAPI PET has high accuracy and its sensitivity is at a high level for the diagnostic evaluation of digestive system tumors. Clinicians, nuclear medicine physicians, and radiologists may consider using [68Ga]Ga-FAPI PET/CT or PET/MR in the evaluation of primary tumors, lymph node metastases, and distant metastases in digestive system tumors.

Impact of 68 Ga-FAPI-04 PET/CT on Staging and Therapeutic Management in Patients With Digestive System Tumors.

PURPOSE: We aimed to determine the impact of fibroblast activation protein inhibitor (FAPI)-directed molecular imaging on staging and therapeutic management in patients affected with digestive system tumors when compared with guideline-compatible imaging (GCI). PATIENTS AND METHODS: Thirty-two patients with tumors of the digestive system were included: colon adenocarcinoma, 2/32 (6.3%); hepatocellular carcinoma (HCC), 6/32 (18.8%); pancreatic duct adenocarcinoma (PDAC), 6/32 (18.8%), and gastroenteropancreatic neuroendocrine neoplasms, 18/32 (56.3%). All patients underwent GCI and 68 Ga-FAPI-04 PET/CT within median 4 days. Staging outcomes and subsequent treatment decisions were compared between GCI and 68 Ga-FAPI-04 PET/CT. RESULTS: Compared with GCI, 68 Ga-FAPI-04 PET/CT led to staging changes in 15/32 patients (46.9%). Among those, downstaging was recorded in 3/15 cases (20.0%) and upstaging in the remaining 12/15 patients (HCC, 4/12 [33.3%]; PDAC, 4/12 [33.3%]; neuroendocrine neoplasms, 3/12 [25%]; colon adenocarcinoma, 1/12 [8.3%]). Therapeutic management was impacted in 8/32 patients (25.0%), including 4 instances of major and 4 instances of minor therapeutic changes. The highest proportion of treatment modifications was observed in patients diagnosed with PDAC and HCC in 6/8 (75%). CONCLUSIONS: In patients affected with digestive system tumors, 68 Ga-FAPI-04 PET/CT resulted in staging changes in more than 46% and therapeutic modifications in 25% of the cases, in particular in patients with HCC and PDAC. In clinical routine, such findings may favor a more widespread adoption of FAP-directed imaging in those tumor types.

Synthesis and Evaluation of 68Ga-NOTA-COG1410 Targeting to TREM2 of TAMs as a Specific PET Probe for Digestive Tumor Diagnosis.

Currently, positron emission tomography/computed tomography (PET/CT) is an important method for the discovery and diagnosis of digestive system tumors. However, the shortage of specific imaging tracer limits the effectiveness of PET. Triggering receptor expressed on myeloid cells 2 (TREM2) as an M2-type macrophage biomarker is receiving much attention considering its high abundance and specificity, which could be an ideal target for PET imaging. First, the expression of TREM2 in tumors and corresponding normal tissues was analyzed using a database and was verified by tissue microarrays and murine model slices, and we found that the expression of TREM2 in tumor tissues was significantly higher than that in normal tissues and enteritis tissues. Then, we established a macrophage co-culture system to obtain tumor-associated macrophages (TAMs). Compared with M1-type macrophages and tumor cells, TAMs had a higher expression level of TREM2. The novel radioligand 68Ga-NOTA-COG1410 was successfully synthesized for TREM2 targeting PET imaging. The biodistribution and micro-PET/CT results showed high uptake of 68Ga-NOTA-COG1410 in the tumor but not in areas of inflammation. The data testified that 68Ga-NOTA-COG1410 was a specific radioligand targeting TREM2, which could be used to distinguish tumors from inflammation. Using 68Ga-NOTA-COG1410, the effectiveness of PET on digestive tumors imaging may be enhanced.

FAPI PET/CT research progress in digestive system tumours.

18F-fluorodeoxyglucose positron emission tomography/computed tomography has been used in clinical practice for many years. This modality is of great value for tumour diagnosis, staging, and efficacy evaluations, but it has many limitations in the diagnosis and treatment of digestive system tumours. Fibroblast activation protein is highly expressed in gastrointestinal tumours. Various isotope-labelled fibroblast activation protein inhibitors are widely used in clinical research. These inhibitors have low background uptake in the brain, liver and oral/pharyngeal mucosa and show good contrast between the tumour and background, which makes up for the lack of fluorodeoxyglucose in the diagnosis of digestive system tumours. It better displays the primary tumours, metastases and regional lymph nodes of digestive system tumours, such as oesophageal cancer, gastric cancer and liver cancer, and also provides a new method for treating these tumours. Based on this background, this article introduces the current research status of fibroblast activation protein inhibitor positron emission tomography/computed tomography in various types of digestive system malignant tumours to provide more valuable information for diagnosing and treating digestive system tumours.

Use of Radiomics to Predict Response to Immunotherapy of Malignant Tumors of the Digestive System.

BACKGROUND Despite the promising results of immunotherapy in cancer treatment, new response patterns, including pseudoprogression and hyperprogression, have been observed. Radiomics is the automated extraction of high-fidelity, high-dimensional imaging features from standard medical images, allowing comprehensive visualization and characterization of the tissue of interest and corresponding microenvironment. This study assessed whether radiomics can predict response to immunotherapy in patients with malignant tumors of the digestive system. MATERIAL AND METHODS Computed tomography (CT) images of patients with malignant tumors of the digestive system obtained at baseline and after immunotherapy were subjected to radiomics analyses. Radiomics features were extracted from each image. The formula of the screened features and the final predictive model were obtained using the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm. RESULTS Imaging analysis was feasible in 87 patients, including 3 with pseudoprogression and 7 with hyperprogression. One hundred ten radiomics features were obtained before and after treatment, including 109 features of the target lesions and 1 of the aorta. Four models were constructed, with the model constructed from baseline and post-treatment CT features having the best classification performance, with a sensitivity, specificity, and AUC of 83.3%, 88.9%, and 0.806, respectively. CONCLUSIONS Radiomics can predict the response of patients with malignant tumors of the digestive system to immunotherapy and can supplement conventional evaluations of response.

Multivisceral robotic resection: a glimpse into the future of minimally invasive abdominal surgery.

A 62-year-old man was referred to the Hepato-Pancreato-Biliary (HPB) surgeons with left upper quadrant discomfort. The initial investigations and CT scans revealed a tumour in the pancreatic tail with liver metastases, confirmed on MRI. It was initially thought to be an adenocarcinoma; however, further investigations found that it was a grade 1 neuroendocrine tumour with Ki 67 at 1% and it was agreed that he would undergo a total robotic surgery involving resection of the locally advanced tumour of the tail of pancreas, with the involvement of the stomach, and splenic flexure of the colon with liver metastases. The resulting procedure was a total robotic distal pancreatectomy, splenectomy, sleeve resection of stomach, cholecystectomy, atypical resection of two liver lesions and microwave ablation of multiple liver lesions. Four days post-operatively, he was discharged from hospital and commenced adjuvant chemotherapy. He currently enjoys a good quality of life.

MR Imaging Texture Analysis in the Abdomen and Pelvis.

Add "which is a" before "distribution"? Texture analysis (TA) is a form of radiomics that refers to quantitative measurements of the histogram, distribution and/or relationship of pixel intensities or gray scales within a region of interest on an image. TA can be applied to MR images of the abdomen and pelvis, with the main strength quantitative analysis of pixel intensities and heterogeneity rather than subjective/qualitative analysis. There are multiple limitations of MRTA. Despite these limitations, there is a growing body of literature supporting MRTA. This review discusses application of MRTA to the abdomen and pelvis.

Understanding the Lymphatics: Review of the N Category in the Updated TNM Staging of Cancers of the Digestive System.

OBJECTIVE. The N category has been significantly updated in the 8th edition of the American Joint Committee on Cancer's TNM classification. To ensure correct tumor staging, prognosis, and management, it is critical to be aware of these changes. This article reviews the updated N category, organ-specific regional lymph nodes, and lymphatic drainage pathways for cancers of the digestive system from the esophagus to the anal canal. CONCLUSION. Detection of lymph node involvement may be challenging, and knowledge of nodal characteristics, lymphatic drainage pathways, and imaging modalities is essential to optimize detection rate to ensure accurate staging, prognosis estimation, and streamlined management.

Image Quality Assessment of Abdominal CT by Use of New Deep Learning Image Reconstruction: Initial Experience.

OBJECTIVE. The purpose of this study was to perform quantitative and qualitative evaluation of a deep learning image reconstruction (DLIR) algorithm in contrast-enhanced oncologic CT of the abdomen. MATERIALS AND METHODS. Retrospective review (April-May 2019) of the cases of adults undergoing oncologic staging with portal venous phase abdominal CT was conducted for evaluation of standard 30% adaptive statistical iterative reconstruction V (30% ASIR-V) reconstruction compared with DLIR at low, medium, and high strengths. Attenuation and noise measurements were performed. Two radiologists, blinded to examination details, scored six categories while comparing reconstructions for overall image quality, lesion diagnostic confidence, artifacts, image noise and texture, lesion conspicuity, and resolution. RESULTS. DLIR had a better contrast-to-noise ratio than 30% ASIR-V did; high-strength DLIR performed the best. High-strength DLIR was associated with 47% reduction in noise, resulting in a 92-94% increase in contrast-to-noise ratio compared with that of 30% ASIR-V. For overall image quality and image noise and texture, DLIR scored significantly higher than 30% ASIR-V with significantly higher scores as DLIR strength increased. A total of 193 lesions were identified. The lesion diagnostic confidence, conspicuity, and artifact scores were significantly higher for all DLIR levels than for 30% ASIR-V. There was no significant difference in perceived resolution between the reconstruction methods. CONCLUSION. Compared with 30% ASIR-V, DLIR improved CT evaluation of the abdomen in the portal venous phase. DLIR strength should be chosen to balance the degree of desired denoising for a clinical task relative to mild blurring, which increases with progressively higher DLIR strengths.

Tumor Seeding along the Puncture Tract in CT-Guided Interstitial High-Dose-Rate Brachytherapy.

PURPOSE: To quantify the occurrence of tumor seeding in computed tomography (CT)-guided high-dose-rate brachytherapy (HDRBT) and to identify potential risk factors. MATERIALS AND METHODS: CT-HDRBT is a minimally invasive therapeutic option for local ablation of unresectable tumors. The procedure involves CT-guided placement of an enclosed catheter and high-dose-rate brachytherapy using iridium-192. Transcutaneous puncture of a tumor with subsequent retraction of the applicator has the potential risk of tumor seeding along the puncture tract. A total of 1,765 consecutive CT-HDRBT procedures were performed at this center between 2006 and 2017 and were retrospectively analyzed. In addition, a distinction was made between whether the puncture tract was irradiated or not. Follow-up imaging datasets were evaluated for tumor seeding along the former puncture tracts. Descriptive and exploratory statistical analyses of the data were performed. RESULTS: Tumor seeding was observed in 25 cases (25 of 1,765 cases [1.5%]). A total of 0.008 cases occurred per person-age. Patient age was identified as a potential risk factor with an odds ratio of 1.046 (95% confidence interval, 1.003-1.091; P = .04). There were no differences between whether the puncture tract was irradiated or not (P = .552). CONCLUSIONS: Tumor seeding along the puncture tract can occur in CT-HDRBT but is rare.

Clinical impact of FDG PET/CT in alimentary tract malignancies: an updated review.

The use of 18F-fluorodeoxyglucose (FDG) positron emission tomography combined with computed tomography (PET/CT) is well established in the evaluation of alimentary tract malignancies. This review of the literature and demonstration of correlative images focuses on the current role of PET/CT in the diagnosis (including pathologic/clinical staging) and post-therapy follow-up of esophageal, gastric, and colorectal cancers. PET/CT provides utility in the management of esophageal cancer, including detection of distant disease prior to resection. In gastric cancer, PET/CT is useful in detecting solid organ metastases and in characterizing responders vs. non-responders after neoadjuvant chemotherapy, the latter of which have poorer overall survival. In patients with GIST tumors, PET/CT also determines response to imatinib therapy with greater expedience as compared to CECT. For colorectal cancer, PET/CT has proven helpful in detecting hepatic and other distant metastases, treatment response, and differentiating post-radiation changes from tumor recurrence. Our review also highlights several pitfalls in PET/CT interpretation of alimentary tract lesions.

Stent placement with iodine-125 seeds strand effectively extends the duration of stent patency and survival in patients with unresectable malignant obstructive jaundice.

Background: This study aimed to compare the treatment outcomes and safety between stent placement with or without Iodine-125 (125I) seeds strand for patients with unresectable malignant obstructive jaundice (MOJ).Methods: A total of 84 patients with unresectable MOJ treated in our hospital were retrospectively included and divided into the stent group (n = 54) undergoing biliary stent placement and the stent + seeds group (n = 30) receiving stent placement with 125I seeds strand. The therapeutic outcome, postoperative complications, duration of patient survival and stent patency were compared between groups. Kaplan-Meier survival analysis was performed to compare the duration of patient survival and stent patency between groups. Cox-regression analysis was performed to investigate predictive factors for disease-free survival and overall survival.Results: The stent + seeds group had significantly longer duration of patency (231.57 ± 256.54 vs. 110.37 ± 120.52) and overall survival (310.57 ± 330.54 vs. 173.15 ± 219.40) than the stent group (both p < .05). In addition, Kaplan-Meier survival analysis confirmed that the stent + seeds group had longer duration of patency (log-rank test, p = .001) and higher overall survival rate (log-rank test, p = .020) than the stent group. Furthermore, Cox-regression analysis demonstrated that treatment methods was an independent factor associated with disease-free survival (HR: 0.36, 95% CI: 0.19-0.70; p = .003) and overall survival (HR: 1.01, 95% CI: 1.00-1.01; p < .001).Conclusion: The stent placement with 125I seeds strand can significantly improve the primary patency rate and overall survival time in MOJ patients.

Additional value of contrast-enhanced ultrasound (CEUS) on arterial phase non-hyperenhancement observations (≥ 2 cm) of CT/MRI for high-risk patients: focusing on the CT/MRI LI-RADS categories LR-3 and LR-4.

PURPOSE: To determine the added value of CEUS on arterial phase non-hyperenhancement (APNHE) observations (LR-3 and LR-4) of CT/MRI in high-risk patients. METHODS: Forty-three patients with APNHE observations (≥ 2 cm) from CT/MRI were prospectively enrolled in this IRB-approved study and underwent CEUS. All observations were assessed by LI-RADS for CT/MRI and CEUS. The hemodynamic findings were compared. The mean follow-up period was 11.8 ± 2.1 months. Reference standard was made on 34-APNHE observations based on biopsy (n = 2), surgery (n = 2), and follow-up image (n = 30). RESULTS: The median of observation size was 2.3 cm (IQR 2.0-2.5 cm). Among the 43-APNHE observations, 12-observations (27.9%) were further presented as arterial phase hyperenhancement (APHE) in CEUS with early (n = 1, CEUS LR-M), late (n = 10, CEUS LR-5), or no (n = 1, CEUS LR-4) washout. Compared to CT, CEUS presented concordant enhancement patterns in 16 (44.4%) in AP and 20 (55.6%) in PVP, respectively. Similarly, 13 (59.1%) and 14 (63.6%) observations showed concordant enhancement patterns between CEUS and MRI in AP and PVP, respectively. Of the 34-APNHE observations with final diagnosis (hepatocellular carcinoma [HCC] n = 12; intrahepatic cholangiocarcinoma [IHCC], n = 1; non-malignancy, n = 21), 4 HCCs (33.3%) and 1 IHCC (100%) were additionally diagnosed by CEUS, while 1 non-malignant lesion (4.5%) was misdiagnosed as HCC by CEUS. CONCLUSION: Adding CEUS to APNHE observations from CT/MRI would be useful not only for definitely diagnosing HCC (CEUS LR-5) but also for other malignancies (CEUS LR-M). The discordance of dynamic features between the LI-RADS for CEUS and CT/MRI may reflect the different properties of contrast media, although the systems are not interchangeable.

Enhancement pattern mapping technique for improving contrast-to-noise ratios and detectability of hepatobiliary tumors on multiphase computed tomography.

PURPOSE: Currently, radiologists use tumor-to-normal tissue contrast across multiphase computed tomography (MPCT) for lesion detection. Here, we developed a novel voxel-based enhancement pattern mapping (EPM) technique and investigated its ability to improve contrast-to-noise ratios (CNRs) in a phantom study and in patients with hepatobiliary cancers. METHODS: The EPM algorithm is based on the root mean square deviation between each voxel and a normal liver enhancement model using patient-specific (EPM-PA) or population data (EPM-PO). We created a phantom consisting of liver tissue and tumors with distinct enhancement signals under varying tumor sizes, motion, and noise. We also retrospectively evaluated 89 patients with hepatobiliary cancers who underwent active breath-hold MPCT between 2016 and 2017. MPCT phases were registered using a three-dimensional deformable image registration algorithm. For the patient study, CNRs of tumor to adjacent tissue across MPCT phases, EPM-PA and EPM-PO were measured and compared. RESULTS: EPM resulted in statistically significant CNR improvement (P < 0.05) for tumor sizes down to 3 mm, but the CNR improvement was significantly affected by tumor motion and image noise. Eighty-two of 89 hepatobiliary cases showed CNR improvement with EPM (PA or PO) over grayscale MPCT, by an average factor of 1.4, 1.6, and 1.5 for cholangiocarcinoma, hepatocellular carcinoma, and colorectal liver metastasis, respectively (P < 0.05 for all). CONCLUSIONS: EPM increases CNR compared with grayscale MPCT for primary and secondary hepatobiliary cancers. This new visualization method derived from MPCT datasets may have applications for early cancer detection, radiomic characterization, tumor treatment response, and segmentation. IMPLICATIONS FOR PATIENT CARE: We developed a voxel-wise enhancement pattern mapping (EPM) technique to improve the contrast-to-noise ratio (CNR) of multiphase CT. The improvement in CNR was observed in datasets of patients with cholangiocarcinoma, hepatocellular carcinoma, and colorectal liver metastasis. EPM has the potential to be clinically useful for cancers with regard to early detection, radiomic characterization, response, and segmentation.

Long-Term Outcomes of Endoscopic Papillectomy for Ampullary Adenomas.

BACKGROUND AND AIMS: Endoscopic papillectomy is a safe and effective treatment for ampullary adenomas and has mostly replaced surgical local resection. Recent data have discussed the role of endoscopic removal of laterally spreading adenomas associated with ampullary adenomas. We evaluated our long-term results of endoscopic papillectomy for ampullary adenomas. METHODS: We retrospectively analyzed patients who underwent endoscopic papillectomy of biopsy-proven adenomas at our tertiary center between 1994 and 2017. Clinical success was defined as complete excision of an adenoma with no evidence of recurrence during follow-up, no evidence of cancer, and without the need for surgery. RESULTS: A total of 161 patients (73M/88F) with a mean age of 61 (range 19-93) were included. Mean adenoma size was 20 mm (range 5-70). In total, 114/161 patients continued endoscopic surveillance for a minimum of 6 months with a median follow-up of 30 months (range 6-283). Recurrent adenomas were diagnosed in 8 patients (7%) after a median of 36 months (range 12-138). Clinical success was 83%; 35 laterally spreading adenomas were treated, which were larger than adenomas confined to the papilla (mean size 38 mm vs 15 mm, P < 0.05) and required more piecemeal resections (77% vs 15%, P < 0.05). However, no difference was found in recurrence rates between the two groups (8% vs 4%, P = 0.26); 24/161 (15%) of patients had adverse events including bleeding (6%) and pancreatitis (7%). CONCLUSIONS: Endoscopic papillectomy is a safe and effective treatment for ampullary adenomas, including laterally spreading ones. Long-term surveillance demonstrates low recurrence rates at expert centers.

No Advantage of Expanded Polytetrafluoroethylene and Fluorinated Ethylene Propylene-Covered Stents over Uncovered Nitinol Stents for Percutaneous Palliation of Malignant Infrahilar Biliary Obstruction: Results of a Single-Center Prospective Randomized Trial.

PURPOSE: To prove that covered stents are more efficacious than uncovered stents regarding patency, safety, enabling of chemotherapy, and survival in percutaneous palliation of malignant infrahilar biliary obstruction. MATERIALS AND METHODS: After failed endoscopic treatment, 154 patients with obstructive jaundice caused by unresectable infrahilar malignancy were randomly allocated to receive an expanded polytetrafluoroethylene and fluorinated ethylene propylene-covered or an uncovered nitinol stent. Occlusion rate, patency, and survival were assessed. Safety and clinical success in terms of chemotherapy were compared. RESULTS: Three patients were excluded post hoc. Fifteen patients died within 7 d and were excluded from patency analysis. Occlusion rates were 32% (21 of 66) for covered and 29% (20 of 70) for uncovered stents (P = .7). Estimated median patency durations were 308 d (95% confidence interval [CI], 178-438 d) for covered and 442 d (95% CI, 172-712 d) for uncovered stents (P = .1). Serious adverse events (P = 1.0) and 30-day mortality (P = .5) were equivalent between groups. At hospital discharge, median bilirubin reduction of 8 mg/dL was found in both groups (P < .001). In the covered stent group, 35 patients (48%) received palliative chemotherapy, vs 29 (37%) in the uncovered stent group (P = .2). Estimated median survival times were 96 days (95% CI, 68-124 d) with covered stents and 75 days (95% CI, 42-108 d) with uncovered stents (P = .6). CONCLUSIONS: In malignant infrahilar biliary obstruction not amenable to endoscopy, no improvement in patency or survival with percutaneously placed covered stents could be confirmed. Covered and uncovered stent types exhibit similar safety profiles and clinical success rates.

Measurement of body composition in cancer patients using CT planning scan at the third lumbar vertebra / Medición de la composición corporal en pacientes oncológicos mediante la TC de planificación a nivel de la tercera vértebra lumbar

Objective: the main objective was to assess body composition in terms of skeletal muscle index (SMI), myosteatosis, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and intermuscular adipose tissue (IMAT) as an adjunct of information provided by radiotherapy CT planning scan. Material and methods: a sample of 49 patients with lung and digestive cancers underwent a CT scan for radiotherapy treatment, which included measurements at the L3 region. Images were analyzed with a radiotherapy contouring software, using different Hounsfield Unit (HU) settings. Cross-sectional areas (cm2) were automatically computed by summing tissue pixels and multiplying by pixel surface area. Low SMI (cm2/m2) and muscle density (HU) were determined according to the recently established cut-off points. Results: the prevalence of low SMI was detected in 46.94% of patients, being present in 8 women, 4 men with BMI < 25 kg/m2, and 11 men with BMI = 25 kg/m2. The average mean skeletal attenuation of total skeletal muscle area was 29.02 (± 8.66) HU, and myosteatosis was present in 13 women (81.25%) and 31 men (93.94%). Mean SAT was 131.92 (± 76.80) cm2, mean VAT was 133.19 (± 85.28) cm2, and mean IMAT was 11.29 (± 12.86) cm2. Conclusion: skeletal muscle abnormalities are frequently present in cancer patients and a low SMI may also exist even in the presence of overweight. As CT scans are an important tool at any radiation oncology department, they could also be used to offer highly sensitive and specific information about body composition, as well as to detect early malnutrition before starting radiotherapy treatment

Objetivo: evaluar la composición corporal mediante el índice de músculo esquelético (IME), el tejido adiposo visceral (TAV), el tejido adiposo subcutáneo (TAS) y el tejido adiposo intermuscular (TAIM) o la densidad muscular (DM) en pacientes oncológicos antes de iniciar el tratamiento con radioterapia mediante cortes de TAC. Materiales y métodos: se estudiaron 49 pacientes con cáncer de pulmón y del aparato digestivo sometidos a tomografía computarizada con cortes en L3 para la determinación del tratamiento con radioterapia. El tejido adiposo y muscular se cuantificó mediante distintas Unidades Hounsfield (UH) (-29 a +150 para masa muscular, -190 a -30 para TAIM/TAS y -150 a -50 para TAV). Resultados: la prevalencia de un IME bajo se detectó en el 46,94% de los pacientes, estando presente en 8 mujeres, 6 de ellas con un IMC = 25 kg/m². Según la distribución masculina, se identificaron 4 hombres con IMC < 25 kg/m² y 11 hombres con = 25 kg/m². La DM media fue de 29,02 (± 8,66) UH y la mioesteatosis estuvo presente en 13 mujeres (81,25%) y 31 hombres (93,94%). La media del TAS fue de 131,92 (± 76,80) cm², la del TAV de 133,19 (± 85,28) cm² y la del TAIM de 11,29 (± 12,86) cm². Conclusión: las anormalidades del músculo esquelético y la masa grasa son muy frecuentes en los pacientes con cáncer, pudiendo existir un bajo IME incluso en presencia de sobrepeso u obesidad. Teniendo en cuenta que la TAC es una herramienta importante en cualquier departamento de radioterapia, también podría utilizarse para ofrecer información sensible y específica sobre la composición corporal, así como para detectar la malnutrición precoz

Measurement of body composition in cancer patients using CT planning scan at the third lumbar vertebra.

INTRODUCTION: Objective: the main objective was to assess body composition in terms of skeletal muscle index (SMI), myosteatosis, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and intermuscular adipose tissue (IMAT) as an adjunct of information provided by radiotherapy CT planning scan. Material and methods: a sample of 49 patients with lung and digestive cancers underwent a CT scan for radiotherapy treatment, which included measurements at the L3 region. Images were analyzed with a radiotherapy contouring software, using different Hounsfield Unit (HU) settings. Cross-sectional areas (cm2) were automatically computed by summing tissue pixels and multiplying by pixel surface area. Low SMI (cm2/m2) and muscle density (HU) were determined according to the recently established cut-off points. Results: the prevalence of low SMI was detected in 46.94% of patients, being present in 8 women, 4 men with BMI < 25 kg/m2, and 11 men with BMI ≥ 25 kg/m2. The average mean skeletal attenuation of total skeletal muscle area was 29.02 (± 8.66) HU, and myosteatosis was present in 13 women (81.25%) and 31 men (93.94%). Mean SAT was 131.92 (± 76.80) cm2, mean VAT was 133.19 (± 85.28) cm2, and mean IMAT was 11.29 (± 12.86) cm2. Conclusion: skeletal muscle abnormalities are frequently present in cancer patients and a low SMI may also exist even in the presence of overweight. As CT scans are an important tool at any radiation oncology department, they could also be used to offer highly sensitive and specific information about body composition, as well as to detect early malnutrition before starting radiotherapy treatment.

INTRODUCCIÓN: Objetivo: evaluar la composición corporal mediante el índice de músculo esquelético (IME), el tejido adiposo visceral (TAV), el tejido adiposo subcutáneo (TAS) y el tejido adiposo intermuscular (TAIM) o la densidad muscular (DM) en pacientes oncológicos antes de iniciar el tratamiento con radioterapia mediante cortes de TAC. Materiales y métodos: se estudiaron 49 pacientes con cáncer de pulmón y del aparato digestivo sometidos a tomografía computarizada con cortes en L3 para la determinación del tratamiento con radioterapia. El tejido adiposo y muscular se cuantificó mediante distintas Unidades Hounsfield (UH) (-29 a +150 para masa muscular, -190 a -30 para TAIM/TAS y -150 a -50 para TAV). Resultados: la prevalencia de un IME bajo se detectó en el 46,94% de los pacientes, estando presente en 8 mujeres, 6 de ellas con un IMC ≥ 25 kg/m². Según la distribución masculina, se identificaron 4 hombres con IMC < 25 kg/m² y 11 hombres con ≥ 25 kg/m². La DM media fue de 29,02 (± 8,66) UH y la mioesteatosis estuvo presente en 13 mujeres (81,25%) y 31 hombres (93,94%). La media del TAS fue de 131,92 (± 76,80) cm², la del TAV de 133,19 (± 85,28) cm² y la del TAIM de 11,29 (± 12,86) cm². Conclusión: las anormalidades del músculo esquelético y la masa grasa son muy frecuentes en los pacientes con cáncer, pudiendo existir un bajo IME incluso en presencia de sobrepeso u obesidad. Teniendo en cuenta que la TAC es una herramienta importante en cualquier departamento de radioterapia, también podría utilizarse para ofrecer información sensible y específica sobre la composición corporal, así como para detectar la malnutrición precoz.

Imaging Features of Primary Sclerosing Cholangitis: From Diagnosis to Liver Transplant Follow-up.

Primary sclerosing cholangitis (PSC) is a chronic progressive inflammatory disease of the bile ducts that leads to multifocal bile duct fibrosis, strictures, cholestasis, liver parenchymal changes, and ultimately cirrhosis. It more commonly occurs in young adults, with a variety of clinical and imaging manifestations. The cause of the disease is not known, but it has a strong association with inflammatory bowel disease and can overlap with other autoimmune diseases, including autoimmune hepatitis and immunoglobulin G4-related disease. Patients are predisposed to various hepatic and extrahepatic deteriorating complications, such as bile duct and gallbladder calculi, acute bacterial cholangitis, liver abscess, and portal hypertension, as well as malignancies including cholangiocarcinoma (CCA), gallbladder cancer, and colorectal carcinoma. Imaging has an essential role in diagnosis, surveillance, and detection of complications. MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography have high specificity and sensitivity for detection of primary disease and assessment of disease progression. However, many patients with PSC are still diagnosed incidentally at US or CT. Novel imaging techniques such as transient elastography and MR elastography are used to survey the grade of liver fibrosis. Annual cancer surveillance is necessary in all PSC patients to screen for CCA and gallbladder cancer. Familiarity with PSC pathogenesis and imaging features across various classic imaging modalities and novel imaging techniques can aid in correct imaging diagnosis and guide appropriate management. The imaging features of the biliary system and liver parenchyma in PSC across various imaging modalities are reviewed. Imaging characteristics of the differential diagnosis of PSC, clinical associations, and complications are described. Finally, the role of imaging in evaluation of PSC progression, pre-liver transplant assessment, and post-liver transplant disease recurrence are discussed.©RSNA, 2019.