Preliminary Application of Perfusion Imaging in Neoplasm in the Brain and Body with Multi-slice Helical CT

Objective： To evaluate the clinical value of perfusion imaging in neoplasm in the brain and body with Multi-slice helical CT. Methods： Twenty-eight patients with neoplasm were subjected to perfusion imaging with multi-slice helical CT, including 22 patients with brain neoplasm and 6 patients with body neoplasm. At first, CT routine scan was preformed to localize central slices of neoplasm. Then perfusion imaging of 4 and identical slices in central slices of neoplasm was performed by using CT cine scan. Scanning images were transferred into ADW3.1 work-station to create and analyze perfusion images and parameters. Results： Perfusion parameters of cerebral neoplasm had a remarkable increase. But, CBF value of different cerebral neoplasms had partial overlap; CBV value was increased slightly; MTT value had no apparently clinical value; PS value was increased significantly, pituitary neoplasm〉meningoma〉cerebral glioma≈cerebral metastasis. PS value could reveal the characters of cerebral neoplasm and had apparently clinical value. Perfusion parameters of body neoplasms have a remarkable increase too. Body tumors were liable to be interfered by breath movement. Perfusion parameters were helpful to differentiation diagnosis of neoplasm in the brain and body. PS images of neoplasm in the brain and body were helpful to defining tumor outline and finding small tumor. Conclusion： MSCT perfusion imaging provided a precise and relative simple method to quantitatively estimate blood perfusion status in tumors in the brain and body. The technique can be easily implemented on clinical scanners.

Clinical study of stomach neoplasm CT perfusion imaging

Objection:The purpose of this study is preliminarily to discuss stomach perfusion imaging technique with Multi-slice CT and its clinical application value in stomach neoplasm.Methods:Fifteen patients with known stomach neoplasm performed perfusion imaging with 4 or 16 slice CT.Performing perfusion imaging in central slice of neoplasm,using CT cine scan,slice thick 10 mm/2i;with high pressure syringe,injecting quickly from right elbow-front vein,dosage 45-50 mL,injec-tion rate 3.5-4.0 mL/s,scanning delay time 5 s,scanning total time 45 s.We performed perfusion CT post-processing using pancreatic mode of perfusion CT software.Blood flow(BF),blood volume(BV),mean transit time(MTT),and permeability surface(PS) of gastric wall and tumor were computed for every case.Results:BF,BV,MTT and PS of gastric tumor were 116.68 ± 90.09 mL/(min·100 g),9.57 ± 8.12 mL/100 g,10.07 ± 7.74 s,20.78 ± 19.68 mL/(min·100g),respectively.The P values for each CT perfusion parameters between gastric tumor and normal gastric wall were 0.001,0.021,0.155 and 0.031,respectively.Conclusion:Perfusion CT can provide hemodynamics of gastric tumors and play a key role in the diagnosis of gastric tumors.It's clinical application prospect will be fully broad.

Utility of CT in differentiating liver metastases of well-differentiated gastroenteropancreatic neuroendocrine neoplasms from poorly-differentiated neuroendocrine neoplasms

Objective： To determine the capability of dynamic enhanced computed tomography（CT） to differentiate liver metastases（LMs） of well-differentiated from poorly-differentiated gastroenteropancreatic neuroendocrine neoplasms（GEP-NENs）.Methods： Patients with LMs of GEP-NENs who underwent dynamic enhanced CT examination in Peking University Cancer Hospital from January 2009 to October 2015 were included and data were retrospectively analyzed. We assessed the qualitative and quantitative CT features to identify the significant differentiating CT features of LMs of poorly-differentiated GEP-NENs from those of well-differentiated GEP-NENs using univariate analysis and a multivariate logistic regression model.Results： The study included 22 patients with LMs of well-differentiated GEP-NENs and 32 patients with LMs of poorly-differentiated GEP-NENs. Univariate analysis revealed statistically significant differences between the LMs of well-and poorly-differentiated GEP-NENs in terms of feeding arteries（36.4% vs. 75.0%, χ2=8.061,P=0.005）, intratumoral neovascularity（18.2% vs. 59.4%, χ2=9.047, P=0.003）, lymphadenopathy（27.3% vs. 81.2%,χ2=15.733, P〈0.001）, tumor-to-aortic ratio in the hepatic arterial and portal venous phase（T-A/AP： 0.297±0.080 vs.0.251±0.059, t=2.437, P=0.018; T-A/PVP： 0.639±0.138 vs. 0.529±0.117, t=3.163, P=0.003） and tumor-to-liver ratio in the hepatic arterial phase（T-L/AP： 1.108±0.267 vs. 0.907±0.240, t=2.882, P=0.006）. The LMs of poorlydifferentiated GEP-NENs showed more feeding arteries, more intratumoral neovascularity, more lymphadenopathy and a lower tumor-to-aortic ratio. Multivariate analysis suggested that intratumoral neovascularity [P=0.015, OR=0.108, 95% confidence interval（95% CI）, 0.018–0.646], lymphadenopathy（P=0.001,OR=0.055, 95% CI, 0.009–0.323） and T-A/PVP（P=0.004, OR=5.3 E–5, 95% CI, 0.000–0.044） were independent factors for differentiating LMs of poorly-differentiated from well-differentiated GEP-NENs.Conclusions： Dynamic enhanced CT features（intratumoral neovascularity, lymphadenopathy and T-A/PVP）are useful in the pathological classification of LMs of GEP-NENs.

Progression of hepatic hyperperfusion disorders revealed during follow-up CT scan of digestive system neoplasm

Objective： The aim of this study was to investigate progression of hepatic hyperperfusion disorders revealed during follow-up contrast material-enhanced multi-slice spiral computed tomography （MSCT） scan of digestive system neoplasm. Methods： Three-phase contrast material-enhanced MSCT were performed during the follow-up in patients with digestive system malignant tumor confirmed histologically. The progression of hepatic hyperperfusion disorders revealed on contrast material-enhanced CT image were investigated at the 2 years follow-up with approximately 6 months interval. Results： The hepatic hyperperfusion disorders were showed in 39 patients on follow-up contrast material-enhanced MSCT scans. Among the 39 patients, initial hyperperfusion disorders were revealed in 6 （15.38%）, 26 （66.67%）, and 7 （17.95%） patients in 6, 12, and 18 months during follow-up respectively. The initial hyperperfusion disorders revealed in 12 months were more frequent than those revealed in 6 months （X2 = 14.82, P 〈 0.05） and 18 months （X2 = 15.02, P 〈 0.05）. Among the 39 patients, the hyperperfusion disorders progressed into liver metastasis based on typical CT findings in 37 （94.87%） patients, and were not obvious changes in 2 （5.13%） patients. Among the 37 patients, the hyperperfusion disorders progressed into metastasis in 10 （25.64%） patients in 6 months after the hyperperfusion disorders were revealed, and in 27（69.23%） patients in 12 months. The hyperperfusion disorders developing into metastasis were more in 12 months than those in 6 months （X2= 14.98, P 〈 0.05）. Conclusion： Most hepatic hyperperfusion disorders revealed at the follow-up of digestive system neoplasm may be early manifestations of liver metastasis. The careful follow-up of hepatic hyperperfusion disorders is necessary.

Pulmonary lymphoma: computed tomography features with pathologic correlation

Objective: The aim of this study was to analyze the CT and pathology features of pulmonary lymphoma and to improve the understanding of this disease. Methods: The CT findings of 23 cases with pulmonary lymphoma were retrospectively analyzed and correlated with histopathology. Results: Of the 23 cases with pulmonary lymphoma, there were Hodgkin lymphoma (5 cases) and non-Hodgkin lymphoma (18 cases). Multiple lesions were assessed in 16 cases and single lesion in 7 cases. The imaging findings were classified into 3 types: lobar and segmental involvement type (9/23 cases, 39.13%), nodular or mass-like involvement type (8/23 cases, 34.78%) and mixed type (6/23 cases, 26.09%). Air bronchogram sign (14/23 cases, 60.8%), CT angiogram sign (12/23 cases, 52.17%), ground glass opacity nodules (3/23 cases, 13.04%) and lesion across pulmonary lobes (4/23,17.39%) were the characteristic features of pulmonary lymphoma. Conclusion: Relative characteristic CT features of pulmonary lymphoma could be revealed, which shows clinical significance in the diagnosis of the disease.

Results of Treating Vertebral Metastases by Percutaneous Vertebroplasty Combined with Interventional Chemotherapy

OBJECTIVE Vertebral metastases are a common manifestation in patients with advanced cancer and treatment is often ineffective. This study was conducted to explore the efficacy of treating vertebral metastases by percutaneous vertebroplasty （PVP） combined with interventional chemotherapy. METHODS Seventy-five patients with vertebral metastases （42 men, 33 women; ages 31-76 years） were divided into 2 groups： 39 cases were treated by PVP combined with chemotherapy （VPCC group）, and 36 cases were treated by PVP alone （VP group）. All procedures were guided by computed tomography （CT） scanning. The results and complications were evaluated by a questionnaire regarding pain and routine follow-up. RESULTS The response rate was significantly higher in the VPCC group than in the VP group （93.0% vs 74.4%, P〈0.05）; total response rates for the VPCC and VP groups were 25.6% and 10.3% respectively. A common complication related to VPCC was transient aggravating pain. CONCLUSION PVP may ameliorate pain, and consolidate the vertebrae of patients with vertebral metastases. Its short-term effect may be enhanced by adding drugs into the bone cement.

Research progresses of dual-layer spectral detector CT for preoperative evaluation on colorectal cancer

Dual-layer spectral detector CT is a new spectrum CT imaging technology based on detector being able to obtain both images similar to true plain and spectral images in one time scanning.The reconstructed multi-parameter spectral images can not only improve image quality,enhance tissue contrast,increase the visualization and detection ability of occult lesions,but also provide qualitative and quantitative analysis of the lesions,so as to provide more imaging information and multi-dimensional diagnostic basis.The research progresses of dual-layer spectral detector CT for preoperative evaluation on colorectal cancer were reviewed in this article.

Contrast-enhanced ultrasound and contrast-enhanced computed tomography for differentiating mass-forming pancreatitis from pancreatic ductal adenocarcinoma:a meta-analysis

Background:Patients with mass-forming pancreatitis(MFP)or pancreatic ductal adenocarcinoma(PDAC)presented similar clinical symptoms,but required different treatment approaches and had different survival outcomes.This meta-analysis aimed to compare the diagnostic performance of contrast-enhanced ultrasound(CEUS)and contrast-enhanced computed tomography(CECT)in differentiating MFP from PDAC.Methods:A literature search was performed in the PubMed,EMBASE(Ovid),Cochrane Library(CENTRAL),China National Knowledge Infrastructure(CNKI),Weipu(VIP),and WanFang databases to identify original studies published from inception to August 20,2021.Studies reporting the diagnostic performances of CEUS and CECT for differentiating MFP from PDAC were included.The meta-analysis was performed with Stata 15.0 software.The outcomes included the pooled sensitivity,specificity,positive likelihood ratio(+LR),negative likelihood ratio(-LR),diagnostic odds ratio(DOR),and summary receiver operating characteristic(SROC)curves of CEUS and CECT.Meta-regression was conducted to investigate heterogeneity.Bayesian network meta-analysis was conducted to indirectly compare the overall diagnostic performance.Results:Twenty-six studies with 2115 pancreatic masses were included.The pooled sensitivity and specificity of CEUS for MFP were 82%(95%confidence interval[CI],73%-88%;I^(2)=0.00%)and 95%(95%CI,90%-97%;I^(2)=63.44%),respectively;the overall+LR,-LR,and DOR values were 15.12(95%CI,7.61-30.01),0.19(95%CI,0.13-0.29),and 78.91(95%CI,30.94-201.27),respectively;and the area under the SROC curve(AUC)was 0.90(95%CI,0.87-92).However,the overall sensitivity and specificity of CECT were 81%(95%CI,75-85%;I^(2)=66.37%)and 94%(95%CI,90-96%;I^(2)=74.87%);the overall+LR,-LR,and DOR values were 12.91(95%CI,7.86-21.20),0.21(95%CI,0.16-0.27),and 62.53(95%CI,34.45-113.51),respectively;and,the SROC AUC was 0.92(95%CI,0.90-0.94).The overall diagnostic accuracy of CEUS was comparable to that of CECT for the differential diagnosis of MFP and PDAC(relative DOR 1.26,95%CI[0.42-3.83],P>0.05).Conclusions:CEUS and CECT have comparable diagnostic performance for differentiating MFP from PDAC,and should be considered as mutually complementary diagnostic tools for suspected focal pancreatic lesions.

Incidental vertebral compression fractures in imaging studies:Lessons not learned by radiologists

AIM:To assess radiologists reporting rates of incidental vertebral compression fractures in imaging studies. METHODS:We performed a review of the current literature on the prevalence and reporting rates of incidental vertebral compression fractures in radiologic examinations. RESULTS:The bibliographic search revealed 12 studies:7 studies using conventional radiology and 5 using multidetector computed tomography(MDCT).The lossof height cut-off to define a vertebral fracture varied from 15%to 25%.Fracture prevalence was high (mean 21.1%;range 9.5%-35%)in both radiographic and MDCT studies(mean 21.6%and 20.2%,respectively).Reporting rates were low with a mean value of 27.4%(range 0%-66.3%)and were significantly lower in MDCT than in radiographic studies(mean 8.1%vs 41.1%).Notably,recent studies showed lower reporting rates than older studies. CONCLUSION:Many scientific studies have confirmed a high prevalence of vertebral compression fractures as incidental findings on imaging studies.However,the underreporting of these fractures,as determined in our study,may negatively affect patient care.

Gastrointestinal autonomic nerve tumors:A surgical point of view

AIM: Gastrointestinal autonomic nerve tumors are uncommon stromal tumors of the intestinal tract. Their histological appearance is similar to that of other gastrointestinal stromal tumors. We report two cases and performed an analysis of the literature by comparing our findings with the available case reports in the medical literature.METHODS: Two patients were admitted with abdominal tumor masses. One occurred in the stomach with large multiple liver metastases and the second originated in Meckel's diverticulum. The latter site has never been reported previously. Both patients underwent surgery. In one patient gastrectomy, right liver resection and colon transversum resection were performed to achieve aggressive tumor debulking. In the other patient the tumor bearing diverticulum was removed.RESULTS: Postoperative recovery of both patients was uneventful. Histological examination, immunohistochemical analysis and electron microscopy revealed the diagnosis of a gastrointestinal autonomic nerve tumor. The patient with the tumor in Meckel's diverticulum died 6 mo after surgery because of pneumonia. The patient with liver metastases have been alive 13 years after initial tumor diagnosis and 7 years after surgery with no evidence of tumor progression. In light of our results, we performed athorough comparison with available literature reports.CONCLUSION: Radical surgical resection of gastrointestinal autonomic nerve tumors seems to be the only available curative approach to date, and long term survival is possibleeven in large metastasized tumors.

多层螺旋CT在喉癌及喉咽癌术前T分级中的作用

喉癌及喉咽癌是头颈部常见恶性肿瘤，手术方式多种多样，其宗旨是彻底切除肿瘤的前提下，尽量保留或重建喉功能，有效改善患者的生活质量，因此术前明确肿瘤侵犯的范围和分期对临床治疗方案的选择有重要价值。笔者应用16层螺旋CT对喉癌及喉咽癌进行术前分析，评价其在术前T分级中的临床应用价值。

Cavitary Pulmonary Metastases: CT Features and Their Correlation with the Pathology of the Primary Malignancy

Objective: To study CT features of cavitary pulmonary metastases and to investigate the pos- sible relationship between CT features and the pathology of the primary lesions. Methods: CT ?ndings of 131 cavitary metastatic nodules in 40 patients with pathologically-proved pulmonary metastases were retrospectively analyzed. A comparison between CT signs and the pathologic types of the primary tumors was made. Results: Cavitary metastases and multiple solid nodules coexisted in all patients. Cavitary metastases presented as bubble (n=41), irregular (n=33), cystic (n=26) or small circular (n=31) cavities, with even (n=61) or uneven (n=70) thickness of the cavity wall. Of 131 cavitary nodules, diameter less than 15 mm was seen in 44, between 15–25 mm in 66, 25–40 mm in 17 and larger than 40 mm in 4 respectively. And the wall thickness of the cavity below 4 mm, between 4–15 mm and over 15 mm was respectively seen in 69, 44 and 18 metastatic nodules. Cavitary pulmonary metastases mainly occurred in patients whose primary malignancy was squamous cell carcinoma (n=13) or adenocarcinoma (n=22). Both squamous cell carcinoma and adenocarcinoma had its own CT characteristics. The occurrence of cavity bore no relationship to its site in the lung. Conclusion: Cavitary pulmonary metastases carries certain CT features and its occurrence is related to the pathologic type of the primary malignancy.

Brain metastasis of hepatocellular carcinoma:A case report and review of the literature

Hepatocellular carcinoma (HCC) is one of the most frequent malignancies in the world. It is more common in far eastern countries and relatively rare in the United States and western European countries where at autopsy it accounts for only 1-2% of malignant rumors, The disease is usually manifested in the the 6^th and 7^th decade of life. HCC is one of the highly malignant neoplasms, Extrahepatic metastases are seen in 64% of patients with HCC. The lungs, regional lymph nodes, kidney, bone marrow and adrenals are common sites of HCC metastasis^[1-3], But, metastasis to brain and skull is extremely rare. Table I shows some of the reported cases of HCC with brain metastasis. These case reports reaffirms the complex and multidisciplinary care of these patients^[4-5].

Eight-year follow-up of locally advanced lymphoepithelioma-like carcinoma at upper urinary tract: A case report

BACKGROUND Urinary tract lymphoepithelioma-like carcinoma is rarely seen.Although it is termed after lymphoepithelioma at the nasopharynx,it behaves more like high grade urothelial carcinoma by immunohistochemical features.Most published literatures focused on its rarity but few discussed results of long-term follow-ups.As no available guidelines are applicable,we postulated that principles should be similar to that of urothelial carcinoma at urinary tract.As of now,this work features the longest follow-up of this cancer at the upper urinary tract.CASE SUMMARY A 63-year-old female had a chief complaint of intermittent left flank pain for 2 mo,along with accompanying symptoms including vomiting and body weight loss,about 7 kg over 2 mo.Laboratory data showed normocytic anemia,mildly poor renal function,and hyperparathyroidism.Urine analysis showed mild hematuria.Computed tomography showed a 4.2-cm-width irregular mass over left renal pelvic and enlarged lymph node at the left renal hilum.Whole-body bone scan was negative of active bone lesions.Biopsy from ureteroscopy showed urothelial carcinoma.Specimen from laparoscopic nephroureterectomy with bladder cuff resection showed lymphoepithelioma-like carcinoma with muscular invasion(pT3).She took adjuvant chemotherapies of 2 cycles and full courses of radiation therapy.No recurrence was observed with designed investigative programs.CONCLUSION Locally advanced urinary tract lymphoepithelioma-like carcinoma could benefit from nephroureterectomy and bladder cuff excision in terms of recurrence-free survival.

Recurrence of hepatocellular carcinoma with rapid growth after spontaneous regression

We report an 80-year-old man who presented with sponta- neous regression of hepatocellular carcinoma(HCC).He complained of sudden right flank pain and low-grade fever. The level of protein induced by vitamin K antagonist(PIVKA)- II was 1 137 mAU/mL.A computed tomography scan in November 2000 demonstrated a low-density mass located in liver S4 with marginal enhancement and a cystic mass of 68 mm×55 mm in liver S6,with slightly high density content and without marginal enhancement.Angiography revealed that the tumor in S4 with a size of 25 mm×20 mm was a typical hypervascular HCC,and transarterial chemoembolization was performed.However,the tumor in S6 was hypovascular and atypical of HCC,and thus no therapy was given.In December 2000,the cystic mass regressed spontaneously to 57 min×44 mm,and aspiration cytology revealed bloody fluid,and the mass was diagnosed cytologically as class I. The tumor in S4 was treated successfully with a 5 mm margin of safety around it.The PIVKA-II level normalized in February 2001.In July 2001,the tumor regressed further but presented with an enhanced area at the posterior margin.In November 2001,the enhanced area extended,and a biopsy revealed well-differentiated HCC,although the previous tumor in S4 disappeared.Angiography demonstrated two tumor stains,one was in S6,which was previously hypovascular, and the other was in S8.Subsequently,the PIVKA-II level started to rise with the doubling time of 2-3 wk,and the tumor grew rapidly despite repeated transarterial embolization with gel foam.In February 2003,the patient died of bleeding into the peritoneal cavity from the tumor that occupied almost the entire right lobe.Considering the acute onset of the symptoms,we speculate that local ischemia possibly due to rapid tumor growth,resulted in intratumoral bleeding and/or hemorrhagic necrosis,and finally spontaneous regression of the initial tumor in S6.

A case of leptospirosis simulating colon cancer with liver metastases

We report a case of a 61-year-old man who presented with fatigue,abdominal pain and hepatomegaly.Computed tomography (CT) of the abdomen showed hepatomegaly and multiple hepatic lesions highly suggestive of metastatic diseases.Due to the endoscopic finding of colon ulcer,colon cancer with liver metastases was suspected.Biochemically a slight increase of transaminases,alkaline phosphatase and gammaglutamyl transpeptidase were present;α- fetoprotein,carcinoembryogenic antigen and carbohydrate 19-9 antigen serum levels were normal.Laboratory and instrumental investigations,including colon and liver biopsies revealed no signs of malignancy.In the light of spontaneous improvement of symptoms and CT findings,his personal history was revaluated revealing direct contact with pigs and their tissues.Diagnosis of leptospirosis was considered and confirmed by detection of an elevated titer of antibodies to leptospira.After two mo,biochemical data,CT and colonoscopy were totally normal.

Diagnostic Value of CT Colonography in Colorectal Carcinoma

OBJECTIVE To investigate the value of CT colonography （CTC） in diagnosis and preoperative staging of colorectal carcinoma.METHODS CTC was performed on 33 patients who were suspected of having colorectal carcinoma. The results of CTC were compared with those of a pathological examination.RESULTS Among the 22 patients who were diagnosed with colorectal carcinoma by CTC, 20 cases were confirmed by pathology. The diagnostic sensitivity and specificity were 100% （20/20） and 84.6% （11/13） respec- tively. The accuracy of showing carcinoma pathologic patterns was 90% （18/20）. The sensitivity and specificity were both 100% in the mass type; 77.8% and 100% in the infiltrating type; 100% and 85.7% in the ulcerated type. The accuracy of staging Dukes＇ carcinbma was 75%. The sensitivity and specificity were 100% and 94.1% for Dukes＇A; 80% and 73.3% for Dukes＇ B： 60% and 100% in Dukes＇ C： 71.4% and 100% for Dukes＇ D.CONCLUSION CTC produces a high success rate and provides considerable diagnostic information for both an accurate diagnosis of colorectal carcinoma and staging before operation,

Perivascular epithelioid cell tumor of the liver:A report of two cases and review of the literature

Perivascular epithelioid cell tumor (PEComa) is a rare tumor which arises from mesenchymal tissues. It is predominant in the uterus,but very rare in the liver. To the best of our knowledge,less than 5 cases of PEComa of the liver have been reported. Herein we present two pathologically proven cases of PEComa of the liver,retrospectively analyze their clinical and imaging features,and review the literature.

Ischemic colitis masquerading as colonic tumor:Case report with review of literature

Ischemic colitis can mimic a carcinoma on computed tomographic (CT) imaging or endoscopic examination. A coexisting colonic carcinoma or another potentially obstructing lesion has also been described in 20% of the cases of ischemic colitis. CT scan can differentiate it from colon cancer in 75% of cases. However, colonoscopy is the preferred method for diagnosing ischemic colitis as it allows for direct visualization with tissue sampling. Varied presentations of ischemic colitis have been described as an ulcerated or submucosal mass or as a narrowed segment of colon with ulcerated mucosa on colonoscopy. Awareness and early recognition of such varied presentations of a common condition is necessary to differentiate from a colonic carcinoma, and to avoid unnecessary surgery and related complications.

Development and validation of a CT-based radiomics nomogram for preoperative prediction of tumor histologic grade in gastric adenocarcinoma

Objectives:To develop and validate a radiomics nomogram for preoperative prediction of tumor histologic grade in gastric adenocarcinoma(GA).Methods:This retrospective study enrolled 592 patients with clinicopathologically confirmed GA(low-grade:n=154;high-grade:n=438)from January 2008 to March 2018 who were divided into training(n=450)and validation(n=142)sets according to the time of computed tomography(CT)examination.Radiomic features were extracted from the portal venous phase CT images.The Mann-Whitney U test and the least absolute shrinkage and selection operator(LASSO)regression model were used for feature selection,data dimension reduction and radiomics signature construction.Multivariable logistic regression analysis was applied to develop the prediction model.The radiomics signature and independent clinicopathologic risk factors were incorporated and presented as a radiomics nomogram.The performance of the nomogram was assessed with respect to its calibration and discrimination.Results:A radiomics signature containing 12 selected features was significantly associated with the histologic grade of GA(P<0.001 for both training and validation sets).A nomogram including the radiomics signature and tumor location as predictors was developed.The model showed both good calibration and good discrimination,in which C-index in the training set,0.752[95%confidence interval(95%CI):0.701-0.803];C-index in the validation set,0.793(95%CI:0.711-0.874).Conclusions:This study developed a radiomics nomogram that incorporates tumor location and radiomics signatures,which can be useful in facilitating preoperative individualized prediction of histologic grade of GA.