CT诊断的肠系膜脂膜炎50例临床特点分析

目的探讨肠系膜脂膜炎(MP)患者的临床特点,以提高临床医生对该病的认识。方法收集山西白求恩医院2013年1月至2017年5月行腹部CT检查并诊断MP住院患者50例临床资料,对其人口学特点、临床特征、辅助检查、治疗及预后进行分析总结。结果 50例MP患者男女比例1∶0.92,发病年龄25~85岁,平均年龄(59.1±14.0)岁,多因腹痛、发热、血尿、淋巴结肿大等就诊,22例合并肿瘤,以淋巴瘤最为多见,16例有腹部手术史。实验室检查多无特殊,所有患者均未行肠系膜病理活检。6例行腹部CT复查,其中1例经激素治疗后病灶显著吸收,其余5例无明显变化。结论 MP常见于中老年人,临床表现多样,易合并肿瘤,淋巴瘤多见,腹部CT是其最重要的诊断手段,当发现MP时,应注意除外是否合并有恶性肿瘤。     

Clinical role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in post-operative follow up of gastric cancer： Initial results

AIM： To evaluate the clinical role of 18F-fluorodeo-xyglucose positron emission and computed tomography （18F-FDG PET/CT） in detection of gastric cancer recurrence after initial surgical resection. METHODS： In the period from January 2007 to May 2008, 23 patients who had previous surgical resection of histopathologically diagnosed gastric cancer underwent a total of 25 18F-FDG PET/CT scans as follow-up visits in our center. The standard of reference for tumor recurrence consisted of histopathologic confirmation or clinical follow-up information for at least 5 mo after PET/CT examinations. RESULTS： PET/CT was positive in 14 patients （61%） and negative in 9 （39%）. When correlated with final diagnosis, which was confirmed by histopathologic evidence of tumor recurrence in 8 of the 23 patients （35%） and by clinical follow-up in 15 （65%）, PET/CT was true positive in 12 patients, false positive in 2, true negative in 8 and false negative in 2. Overall, the accuracy of PET/CT was 82.6%, the negative predictive value （NPV） was 77.7%, and the positive predictive value （PPV） was 85.7%. The 2 false positive PET/CT findings were actually chronic inflammatory tissue lesions. For the two patients with false negativePET/CT, the f inal diagnosis was recurrence of mucinous adenocarcinoma in the anastomosis in one patient and abdominal wall metastasis in the other. Importantly, PET/CT revealed true-positive findings in 11 （47.8%） patients who had negative or no definite findings by CT. PET/CT revealed extra-abdominal metastases in 7 patients and additional esophageal carcinoma in one patient. Clinical treatment decisions were changed in 7 （30.4%） patients after introducing PET/CT into their conventional post-operative follow-up program. CONCLUSION： Whole body 18F-FDG PET/CT was highly effective in discriminating true recurrence in post-operative patients with gastric cancer and had important impacts on clinical decisions in a considerable portion of patients.     

Usefulness of 18F-fluorodeoxyglucose positron emission tomography in differential diagnosis and staging of cholangiocarcinomas

Background and Aim: ¹⁸F‐Fluoro‐2‐deoxy‐d ‐glucose positron emission tomography (¹⁸FDG‐PET) is promising for diagnosis and treatment of various malignancies. The aim of this study was to evaluate the clinical usefulness of ¹⁸FDG‐PET in differential diagnosis and staging of cholangiocarcinomas according to the intrahepatic, perihilar and common bile duct lesions and to compare with computerized tomography (CT) scan. Methods: From January 2000 to September 2003, 54 patients with suspected cholangiocarcinoma underwent abdominal CT scan and ¹⁸FDG‐PET within a 2‐week period. The PET images were analyzed visually and semiquantitatively. Results: The overall accuracy of ¹⁸FDG‐PET for discriminating malignant diseases of bile duct from benign conditions was slightly higher than that of CT scan (88.9% vs 81.5%). The sensitivity of ¹⁸FDG‐PET in perihilar cholangiocarcinoma was lower than the value of intrahepatic and common bile duct cancers (83.3% vs 91.3%, 90.9%); moreover, in cases of perihilar cancer, the sensitivity of ¹⁸FDG‐PET was lower than that of CT scans (83.3% vs 91.7%). ¹⁸FDG‐PET detected nine distant metastatic lesions not found by other imaging studies and excluded two patients who potentially had resectable condition in other imaging studies from unnecessary laparotomy. Conclusion: The clinical usefulness of ¹⁸FDG‐PET in differential diagnosis of bile duct cancers is related to the site of primary disease. Although it is a helpful method for differential diagnosis especially in cases of intrahepatic and common bile duct cancers, ¹⁸FDG‐PET can not provide confirmative clues in perihilar cholangiocarcinoma. ¹⁸FDG‐PET may hold promise in the detection of hidden distant metastasis and can play an additional role in the evaluation of resectability. ¹⁸FDG‐PET can be complementary to CT scan in diagnosing and staging of cholangiocarcinoma.     

Mesenteritic panniculitis: detection by abdominal ultrasonography.

OBJECTIVE: to describe the findings that allowed us to detect mesenteric panniculitis in sonographic abdominal studies. PATIENTS AND METHODS: we retrospectively evaluated the images of 10 patients diagnosed of mesenteric panniculitis, initially detected by sonography. Diagnosis was confirmed by computed tomography (CT) in all cases, and by surgical biopsy in one of them. Two patients were symptomatic, and it was an incidental finding in the remaining eight cases. RESULTS: the characteristic sonographic appearance consisted of thickening of mesenteric fat around mesenteric vessels, with an elliptical or rounded shape, a convex or lobulated and well-defined anterior border and an homogeneous or slightly heterogeneous structure, with nodular images in three of the cases. Mesenteric vessels were identified, without evidence of distortion. There was a reduction of compressibility in relation to normal mesenteric tissue. CONCLUSION: although we cannot presently state the specificity of the findings described, mesenteric panniculitis can be detected by abdominal sonography. This technique provides guidance for the diagnosis and, eventually, percutaneous biopsy.     

肠系膜急性闭合性损伤的CT影像学特征及临床分析

目的通过对腹部闭合性外伤肠及肠系膜损伤的术前CT检查影像学表现与临床手术进行对比,探讨CT检查在腹部外伤肠及肠系膜损伤影像学表现及诊断优势,从而提高CT影像在肠及肠系膜损伤中的诊断符合率。 方法选取2008至2020年40例中山市东升医院收治疑似腹部闭合性损伤患者,均实施CT检查,将患者的CT检查结果与确诊结果进行对比,总结CT影像检查的诊断符合率,不同肠系膜损伤患者的CT影像学特征。 结果CT诊断符合率、漏诊率分别为97.5%、2.5%,与确诊结果比较,差异无统计学意义(P>0.05);CT检查的影像学特征有腹腔游离气体、腹腔以及肠间隙积血与积液、肠壁增厚水肿及肠壁血肿及肠系膜水肿。 结论CT检查在肠系膜急性闭合性损伤患者诊断中效果理想,其影像学特征显著,可鉴别不同类型肠系膜损伤,且诊断符合率高。     

A prospective study assessing the efficacy of abdominal computed tomography scan without bowel preparation in diagnosing intestinal wall and luminal lesions in patients presenting to the emergency room with abdominal complaints

AIM: To evaluate the positive predictive value of abdominal non-prepared computed tomography (CT) for diagnosing intestinal lumen or wall lesions in patients presenting to the emergency room (ER) with abdominal complaints. METHODS: For 1-year we prospectively evaluated all ER patients hospitalized after abdominal CT scan detected either intraluminal or intestinal wall lesions. These patients underwent colonoscopy serving as gold standard. Patients with prior abdominal pathology or CT findings of appendicitis or diverticulitis were excluded. RESULTS: Five hundred and sixty-eight abdominopelvic CT scans were performed in the ER, 96 had positive colonic findings. Sixty-two patients were excluded, 46 because of diverticulitis or appendicitis, 16 because of prior abdominal pathology. Of the remaining 34 patients, 14 did not undergo colonoscopy during hospitalization. Twenty eligible patients were included in the study. The positive predictive value of the CT scans performed in the ER was calculated to be 45% (95% CI 25-67). CONCLUSION: CT findings correlated with colonoscopic findings only in approximately half of the cases. Relying on non-prepared CT scan findings in planning patient management and colonoscopy may lead to unnecessary diagnostic work-ups.     

18FDG-positron emission tomography/computed tomography (PET/CT) scanning in thyroid nodules with nondiagnostic cytology

Objective To assess the role of positron emission tomography/computed tomography (PET/CT) scans with ¹⁸FDG (¹⁸FDG‐PET/CT) in the evaluation of thyroid nodules with nondiagnostic cytology. Subjects and methods Eighty‐eight patients with a single euthyroid nodule and repeatedly nondiagnostic ultrasound‐guided fine‐needle cytology (US‐FNC) were enrolled in the present study. Nodules concentrating ¹⁸FDG were considered positive (i.e. suspicious for malignancy). Histological findings were obtained after surgery in all patients. Results None of 41 patients with negative ¹⁸FDG‐PET/CT scan had a final histological diagnosis of malignancy (i.e. no false‐negative results). Twenty‐nine patients with final histological diagnosis of thyroid cancer had positive ¹⁸FDG‐PET/CT scan. Eighteen patients with final histological diagnosis of benign lesions (including four with follicular adenomas) also had positive ¹⁸FDG‐PET/CT scans. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were 100%, 69%, 79%, 62% and 100%, respectively. Conclusions A negative ¹⁸FDG‐PET/CT scan accurately excludes malignancy in thyroid nodules with non‐diagnostic US‐FNC procedures. Histology is still necessary to distinguish benign from malignant disease in ¹⁸FDG‐PET/CT‐positive nodules, but unnecessary surgery could have been reduced from 88 to 41 cases (46%) in our series.     

Two cases of mesenteric panniculitis]

Two patients with mesenteric panniculitis are presented. In the first patient, a provisional diagnosis of ileus was made, based on the clinical features and imaging data. Laparotomic findings showed that the ileum was bound tightly by a fibrous strip and dilated, with thickened and swollen mesentery. Incision of the fibrous strip was performed, and the clinical symptoms were improved. The second patient was strongly suspected to have mesenteric panniculitis, from characteristic features on abdominal computed tomography and barium enema. Conservative therapy was effective in this case. We emphasize the variety of clinical courses in mesenteric panniculitis, requiring selection of the most suitable treatment.     

Paraaortic lymph node metastasis in patients with intra- abdominal malignancies： CT vs PET

AIM： To compare the diagnostic accuracy of computed tomography （CT） and positron emission tomography （PET） for the preoperative detection of paraaortic lymph node （PAN） metastasis in patients with intra- abdominal malignancies. METHODS： Sixty-six patients with intra-abdominal malignancies who underwent both CT and PET before lymphadenectomy were included in this study. Histopathologicaliy, 13 patients had metastatic PAN, while 53 had non-metastatic PAN. The CT criteria for metastasis were： short diameter ：）f 〉 8 mm, Iobular or irregular shape, and/or combined ancillary findings, including necrosis, conglomeration, vessel encasement, and infiltration. The PET criterion was positive fluorodeoxyglucose （FDG） uptake. The sensitivity, specificity, positive predictive value （PPV）, negative predictive value （NPV）, and accuracy of both modalities were compared with the pathologic findings, and the false positive and false negative cases with both CT and PET were analyzed.RESULTS： The sensitivity, specificity, PPV, NPV, and accuracy of CT were 61.5%, 84.9%, 50%, 90% and 80.3%, respectively. For PET, the percentages were 46.2%, 100%, 100%, 88.3%, and 89.4%. Additionally, there were 8 false positive CT cases （8/53, 15.1%） and zero false positive PET cases. Of the 13 metastatic PANs, there were 5 false negative CT scans （38.5%） and 7 （53.9%） false negative PET scans.CONCLUSION： For detecting PAN metastasis, CT is more sensitive than PET, while PET is more specific.     

Diagnostic value of 18 F-FDG PET/CT in patients with fever of unknown origin

This study investigates the diagnostic value of (18) F-fluorodeoxyglucose positron emission tomography/computed tomography ((18) F-FDG PET/CT) in patients with 109 classical fever of unknown origin (FUO). Of the 48 (18) F-FDG PET/CT scans, 41 (85.4%) were interpreted as abnormal, and 25 (52.1% of all scans) were considered clinically helpful. The final cause of fever was determined in 41 patients (85.4%); infection (25%), malignancy (12.5%), non-infectious inflammatory disease (16.7%) and miscellaneous causes (31.3%). (18) F-FDG PET/CT contributed to the final diagnosis of FUO in 65.8%.     

(18)F-DG PET/CT in detection of recurrence and metastasis of colorectal cancer

AIM To evaluate the value of 18F-DG PET/CT in detecting recurrence and/or metastasis of colorectal cancer (CRC).METHODS Combined visual analysis with semiquantitative analysis, the 18F-DG PET/CT wholebody imaging results and the corresponding clinical data of 68 postoperative CRC patients including 48 male and 20 female with average age of 58.1 were analyzed retrospectively.RESULTS Recurrence and/or metastasis were confirmed in 56 patients in the clinical follow-up after the PET/CT imaging. The sensitivity of PET/CT diagnosis of CRC recurrence and/or metastasis was 94.6%, and the specificity was 83.3%. The positive predictive value (PPV)was 96.4% and the negative predictive value (NPV) was 76.9%. PET/CT imaging detected one or more occult malignant lesions in 8 cases where abdominal/pelvic CT and/or ultrasonography showed negative findings, and also detected more lesions than CT or ultrasonography did in 30.4% (17/56) cases. Recurrence and/or metastasis was detected in 91.7% (22/24) cases with elevated serum CEA levels by 18F-DG PET/CT imaging.CONCLUSION 18F-DG PET/CT could detect the recurrence and/or metastasis of CRC with high sensitivity and specificity.     

Positron emission tomography scanning in the assessment of patients with lymphoma

BACKGROUND: The detection of lymphoma by computed tomography (CT) scanning is known to be improved by positron emission tomography (PET) and/or gallium scanning, although the direct comparative accuracy of these imaging modalities remains a subject of ongoing review. AIMS: The aim of the present study was to compare PET scanning with conventional imaging (CT and/or gallium scanning) in patients with lymphoma. METHODS: A retrospective study of 38 patients (25 men; 13 women; median age 39.5 years; range 18.0-81.0 years) who had had PET scans (24 scans at initial staging and 46 scans at restaging, including suspected disease relapse) was carried out. Thirty-one concurrent gallium scans had been performed. Disease was validated with clinical follow up or biopsy. RESULTS: The sensitivities of PET and CT at initial staging were 96 and 71%, respectively. PET identified additional sites of disease compared with CT in 29% of patients. Of the 15 patients who had had all three imaging modalities, the sensitivities of PET, CT and gallium were 93, 67 and 87%, respectively. At treatment completion, the positive predictive values of PET, CT and gallium scans for relapse given a residual mass were 100, 33 and 0%, respectively (P = 0.006 for PET and CT comparison). The negative predictive values of PET, CT and gallium were 76, 0 and 70%, respectively (P-value not significant). In suspected disease relapse, PET results changed management in 50% of patients. CONCLUSION: Compared with CT and gallium scans, PET has superior accuracy in staging and restaging, and its greatest value lies in its positive predictive value for relapse in patients with residual masses.     

Use of 18F-FDG positron emission tomography following allogeneic transplantation to guide adoptive immunotherapy with donor lymphocyte infusions

Fluorine-18 fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) provides valuable prognostic information in the management of lymphoma patients. However, the utility of (18)F-FDG PET following allografting is unclear. We analysed the use of (18)F-FDG PET after allogeneic reduced-intensity transplantation (RIT) performed in our institution. Between June 1998 and January 2002, 55 patients underwent RIT for either Hodgkin or non-Hodgkin lymphoma. At least one (18)F-FDG PET scan was performed during the post-transplant period (median five studies) in 15 (27.2%) of these 55 patients. PET scans were performed after re-staging computed tomography (CT) and were categorised depending on (18)F-FDG uptake. The first PET scan was informative in 11 of 15 patients (73%) and influenced the administration of donor lymphocyte infusions (DLI) in nine: leading to earlier DLI administration in two patients, earlier dose escalation in one, withholding of DLI administration in five and dose reduction in one. In addition, subsequent monitoring with (18)F-FDG PET scans documented a graft-versus-lymphoma effect in five patients (median post-DLI follow-up 33 months, range 13-36 months). These preliminary data suggest that (18)F-FDG PET has a role in guiding DLI administration and monitoring the immunotherapeutic effect in patients after allogeneic transplantation. This retrospective pilot study forms the basis for a prospective study to clarify the utility of (18)F-FDG PET/CT in these patients.     

Bowel wall thickening on computed tomography scan: Inter-observer agreement and correlation with endoscopic findings

Background and Study AimsBowel wall thickening (BWT) on computed tomography (CT) has been frequently reported by radiologists. There are no clear guidelines regarding the level of thickening that is correlated with definite pathology. Radiologists usually rely on their overall subjective impression, and studies on inter-observer agreement (IOA) are lacking. This study evaluated IOA concerning BWT found on abdominal CT and identified the corresponding findings on endoscopy.Patients and MethodsReports of abdominal CTs performed between January 2000 and December 2015 containing the term ‘thickening’ were retrieved from the radiology department database. Corresponding patients who later underwent endoscopy were included. IOA concerning BWT was evaluated using a randomly mixed sample of 80 patients with normal findings or pathological BWT on endoscopy. A search for predictive factors for the subsequent finding of malignancy on endoscopy was performed using multivariate analysis.ResultsDuring the study period, 6142 CT scans described thickening, equivalent to a BWT prevalence of 13.7%. Ninety-one patients (mean age, 58 years) were included in the analysis. Thickening was found most commonly in the stomach (38.5%), followed by the rectum (22%) and small intestine (14%). Twenty-seven patients (29.7%) exhibited diffuse BWT, whereas 64 patients showed localised BWT (70.3%). Biopsy was performed for 64 of 91 patients with endoscopies. Among these patients, 8.8% exhibited normal findings, whereas inflammation and malignancy were discovered in 25 and 51.6% of patients, respectively, with a positive predictive value for malignancy of 0.36. The IOA concerning CT for predicting significantly pathological BWT was moderate (mean κ = 0.6). A strong association was evident between the presence of lymph nodes on CT and the presence of neoplastic lesions.ConclusionOur study strongly recommends endoscopic follow-up of patients exhibiting BWT irrespective of the thickening location, especially if it is associated with lymphadenopathy. IOA between radiologists was moderate.     

Limitations of screening for occult cancer in patients with idiopathic venous thromboembolism

Background: Idiopathic venous thrombosis (IVT) is associated with occult malignancy in 10% of patients. The Trousseau study investigated whether extensive screening using abdominal and chest computed tomography (CT) scans and mammography in women would decrease mortality, compared with limited screening. Here, the costs and test characteristics of these screening strategies are presented, including true- and false-positive findings, sensitivity and specificity. Methods: All investigations performed because of a suspicion of malignancy in the limited or extensive screening groups were collected. Costs were calculated using Dutch healthcare tariffs. Results: A total of 342 and 288 patients with IVT were included in the extensive and the limited screening group, respectively. The prevalences of malignancy and mortality were comparable between these two groups, as were the abnormal findings during routine screening. In 30% of the extensively screened patients, the CT scans or mammography showed abnormalities necessitating further diagnostic work-up; this yielded six malignancies and resulted in a positive predictive value of 6.6%, sensitivity of 33% and specificity of 70%. Mean costs per patient were v 165.17 for the routine and v 530.92 for the extensive screening. Conclusion: Screening using CT scans and mammography results in extra costs due to the high percentage of false-positive findings for which a further diagnostic work-up is indicated.     

Use of integrated FDG PET/CT imaging in pulmonary carcinoid tumours

BACKGROUND: Integrated positron emission tomography (PET)/computed tomography (CT) scanners have been recently introduced in the diagnostic work-up of suspected pulmonary malignancy and demonstrate encouraging results in the staging of nonsmall-cell lung cancer. OBJECTIVE: To evaluate the usefulness of integrated FDG PET/CT in pulmonary carcinoid tumours. SETTING: University hospital. METHODS: We studied 13 patients (mean age +/- 1 SD, 57 +/- 11 years) with pulmonary carcinoid tumours. All patients demonstrated a single pulmonary lesion. Integrated PET/CT scan and surgical resection were performed in all patients. RESULTS: The pulmonary lesion size ranged from 1.1 to 5.0 cm. Final histological diagnosis confirmed 12 typical and one atypical pulmonary carcinoid. Mean proliferation rate of the typical carcinoids was 1.7 +/- 1.4%. None of the patients had recurrent carcinoid disease or died during follow-up (864 +/- 218 days). Mean standardized uptake value (SUV) of (18)F-fluorodeoxyglucose (FDG) in typical carcinoids was 3.0 +/- 1.5 (range 1.2 - 6.6); SUV in the atypical carcinoid was remarkably high with a value of 8.5. The SUV was lower than 2.5 in 6 of 12 patients (50%). Mediastinal lymph node metastases or extrathoracic metastases were not detected in any patient. CONCLUSIONS: (18)F-fluorodeoxyglucose PET/CT imaging improves accurate localization of metabolic activity and thus the interpretation of pulmonary lesions on CT. FDG uptake in pulmonary carcinoid tumours is often lower than expected for malignant tumours. Therefore, surgical resection or biopsy of lesions suspected to be carcinoids should be mandatory, even if they show no hypermetabolism on FDG PET images.     

PET/CT Colonography for the Preoperative Evaluation of the Colon Proximal to the Obstructive Colorectal Cancer

Purpose  This study was designed to evaluate the usefulness of 18-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) colonography in preoperative diagnosis of the tumors proximal to obstructive colorectal cancers, which were defined as cancers that cannot be traversed colonoscopically. Methods  A whole-body PET/CT protocol for tumor staging and a protocol for CT colonography were integrated into one examination. No cathartic bowel preparation was used before this examination. Thirteen prospective patients with obstructive cancer were examined. We compared the detection rates for obstructive colorectal cancers and tumors proximal to the obstruction using air-inflated PET/CT colonography to intraoperative examinations, histopathologic outcome, and follow-up colonoscopy. Results  PET/CT colonography correctly identified all 13 primary obstructive colorectal cancers and all 2 synchronous colon cancers proximal to the obstruction. The two synchronous colon cancers detected at PET/CT colonography were confirmed and removed at single-stage surgical procedures. PET/CT colonography was able to localize all colorectal cancers precisely. There were no false-negative or false-positive proximal colorectal cancers by PET/CT colonography. Other preoperative examinations missed the synchronous colon cancers. Conclusions  In patients with obstructive colorectal cancers, preoperative PET/CT colonography provided valuable anatomic and functional information of the entire colon to properly address surgery of colorectal cancer.     

Endoscopic Ultrasonography Findings in Patients with Non-Specific Changes of the Pancreas on Computed Tomography: A Single-Center Experience

Inconclusive findings on abdominal computerized tomography (CT) scans such as "enlarged or prominent pancreas" are commonly reported; however, their clinical significance is not clearly understood. The objective was to evaluate the efficacy of endoscopic ultrasound (EUS) in a cohort of patients with indeterminate findings on CT. We undertook a retrospective, single-center study at a tertiary care university hospital. About 107 consecutive patients (56 men) underwent EUS evaluation for inconclusive CT findings. The main intervention was EUS with fine needle aspiration (FNA) The main outcome measurement was to describe lesions identified by EUS in this cohort of patients. About 22 patients (21%) had pancreatic adenocarcinoma, 14 (13%) had chronic pancreatitis, 28 (26%) had benign lesions, and 35 patients (33%) had a normal EUS exam. Pancreatic cancer was more likely to be found on EUS in patients with significant weight loss (OR 10.1; 95% CI: 3.3-30.60), hyperbilirubinemia (OR 9; 95% CI: 3-26.0), or common bile duct (CBD) dilatation (OR 3.2; 95% CI: 1.25-8.5). The limitations of the study were that we were unable to control the uniformity of CT interpretation because the scans were reviewed by multiple radiologists. There were also limited follow-up data on patients who had benign lesions or normal EUS. In conclusion, EUS is an effective modality for evaluating pancreatic lesions in patients with inconclusive findings on abdominal CT. This assists in the prompt diagnosis and institution of appropriate treatment strategies for a variety of pancreatic diseases including cancer. In the setting of inconclusive CT findings, patients with hyperbilirubinemia, significant weight loss, or CBD dilatation should undergo EUS evaluation as they are at a higher risk of having underlying pancreatic cancer.     

Diagnostic value of diffusion-weighted magnetic resonance imaging compared with fluorodeoxyglucose positron emission tomography/computed tomography for pancreatic malignancy: a meta-analysis using a hierarchical regression model

Background and Aim: To obtain diagnostic performance of diffusion‐weighted magnetic resonance imaging (DWI) and fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the detection of pancreatic malignancy. Methods: We performed a meta‐analysis of all available studies of the diagnostic performance of DWI and PET/CT for pancreatic malignancy. MEDLINE, EMBASE, Cochrane library and some other databases were searched for initial studies. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR?), and constructed summary receiver operating characteristic curves (SROC) using hierarchical regression models. Results: Across 16 studies with 804 patients, PET/CT sensitivity was 0.87 (95% confidence interval [CI], 0.82, 0.81) and specificity was 0.83 (95% CI, 0.71, 0.91). Overall, LR+ was 5.84 (95% CI, 4.59, 7.42) and LR? was 0.24 (95% CI, 0.17, 0.33). DWI sensitivity was 0.85 (95% CI, 0.74, 0.92) and specificity was 0.91 (95% CI, 0.71, 0.98). LR+ was 9.53 (95% CI, 2.41, 37.65) and LR? was 0.17 (95% CI, 0.09, 0.32). In subgroup analysis, the sensitivity of enhanced versus unenhanced PET/CT in the detection of pancreatic cancer was 0.91 (95% CI, 0.86, 0.96) versus 0.84 (95% CI, 0.78, 0.90) (P > 0.05), the specificity 0.88 (95% CI, 0.73, 1.00) versus 0.81 (95% CI, 0.69, 0.94) (P > 0.05). Conclusion: Positron emission tomography/computed tomography (PET/CT) was highly sensitive and DWI was a highly specific modality in diagnosing patients with pancreatic malignancy. PET/CT and DWI could play different roles in diagnosing pancreatic carcinoma. Enhanced PET/CT seems to be superior to unenhanced PET/CT. Further larger prospective studies are needed to establish its value for diagnosis in pancreatic cancer.