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Purpose To compare the CT features of hepatic metastases of gastro-entero-pancreatic adenocarcinomas with and without neuroendocrine differentiation [NED(+) and NED(-)] and to explore the value of CT features in differentiation of the two groups.Material and Methods From January 2009 to December 2015,abdominal CT scans of 17 pathologically proved cases of NED(+) gastro-entero-pancreatic adenocarcinomas with hepatic metastases and 34 pathologically proved cases of NED(-) hepatic metastases with sex,age and primary site matched were retrospectively reviewed.CT features including hepatic metastases number,size,distribution,shape and enhancement were assessed,as well as presence of lymphadenopathy or ascites.Differences of CT features between the two groups were analyzed.Results Compared with NED(-) group,hepatic metastases of NED(+) group more frequently demonstrated a peripheral enhancement on artery phase (94.1％ vs.44.1％,P＜0.05),and more washout on portal venous phase (41.2％ vs.5.9％,P＜0.05),while hepatic metastases of NED(--) group showed more plateau type (91.2％ vs.58.8％).There was no significant difference of other findings between the two groups (P＞0.05).Logistic regression revealed that enhancement area in hepatic artery phase and enhancement changes in portal venous phase were independent factors for differential diagnosis (P＜0.05).The area under the ROC curve of combining the two features was 0.811 (P＜0.05).Conclusion There are some different CT enhancement features between NED(+) and NED(-) hepatic metastases of gastro-entero-pancreatic adenocarcinomas,which are helpful in differential diagnosis.
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Objective To develop and validate one optimal MR radiomics model for lymph node (LN) re-evaluation of locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotheray (NCRT). Methods Four hundred and seven patients with clinicopathologically confirmed LARC in Beijing Cancer Hospital were included in this study from July 2010 to June 2015. All patients received NCRT before surgery,and underwent T2WI and DWI before and after NCRT.These patients were chronologically divided in the primary cohort(300 patients)and independent validation cohort(107 patients).The predicting model was trained and validated using postoperative pathological findings as truth values. By using radiomics method, we extracted the features of the tumor and the largest LN before and after neoadjuvant therapy, combined different features of the tumor and/or the largest LN before and/or after neoadjuvant therapy,and constructed 4 different prediction models,compared the performance of four predicting models.The optimal model with the highest accuracy was validated in the independent cohort. Decision curve analysis was conducted to determine the clinical usefulness of the radiomics nomograms by quantifying the net benefits at different threshold probabilities in the validation dataset. Results In the primary cohort, the radiomics signatures from 4 models provided an AUC of 0.637, 0.709, 0.753, 0.835, respectively in LN re-evaluation after chemoradiotheray. The diagnostic efficacy of model 4 was much better than that of 1, 2 and 3 model. In the validation cohort, the radiomics signatures provided an AUC of 0.795 for LN re-evaluation after chemoradiotheray. The sensitivity, specificity, positive predictive value, negative predictive value were 0.813, 0.693, 0.531, 0.897, respectively (95% CI: 0.694 to 0.896, 0.647 to 0.911, 0.582 to 0.786, 0.361 to 0.621, 0.792 to 0.952). While the probability of predicting N+ ranges from 17% to 80%, using the proposed radiomics model to predict N+ shows a greater advantage than either the scheme in which all patients were assumed to N+ or the scheme in which all patients are N-. Decision curve analysis demonstrated that the radiomics nomograms were clinically useful. Conclusion With a systematic analysis and comparison of both pre-and post-NCRT MRI data, we constructed an optimal individualized LN re-evaluation model based on MR radiomics, combing primary tumor and the largest LN features, compared with other models (only with pre/post tumor or pre/post largest LN features).
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Objective To evaluate the efficacy of high resolution MR T2WI combined with DWI in evaluation of pathological complete response after neoadjuvant therapy in rectal cancer.Methods Totally 364 patients with locally advanced rectal cancer who recieved neoadjuvant therapy and radical surgery,underwent MR scanning before and after neoadjuvant therapy,were enrolled in this study.The diagnostic efficacy of high resolution MR T2WI and high resolution MR T2WI combined with DWI in evaluation on pathological complete response after neoadjuvant therapy in rectal cancer were compared.Results Finally 49 cases were demonstrated pathologic complete response.Accuracy,sensitivity,specificity,positive predictive value and negative predictive value of high resolution MR T2WI and high resolution MR T2WI combined with DWI in predicting on pathological complete response after neoadjuvant therapy were 82.69％ (301/364),40.82％ (20/49),89.21％ (281/315),37.04％ (20/54),90.65％ (281/310)and 87.36％ (318/364),65.31％ (32/49),90.79％ (286/315),52.46％ (32/61),94.39％ (286/303),respectively.Sensitivity had statiatical significant difference between two methods (x2 =4.96,P=0.03).Conclusion Compared with high-resolution T2WI,the combination of DWI and high-resolution T2WI can improve the diagnostic efficacy in evaluation of pathologic complete response of locally advanced rectal cancer.
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Objective To evaluate the value of MRI performance for the differential diagnosis of atypical solitary metastatic malignant melanoma from spinal hemangioma.Methods Thirteen patients of atypical solitary metastatic malignant melanoma and 40 patients of spinal solitary hemangioma were retrospectively analyzed.Conventional MR imaging (T1WI,T2WI,and fat suppressed T2WI) and enhanced imaging were performed at 1.5T MRI.The signal intensities (SIs) of spinal lesions were qualitatively evaluated on conventional imaging and were described as hypointense,isointense,or hyperintense.The spinal lesions were qualitatively categorized into minimal enhancement,iso-enhancement,slightly hyper-enhancement,or strong enhancement on contrast-enhanced imaging.The lesions' maximum diameter was also measured and the mean value was obtained.Results The qualitative assessment of SIs on T1WI showed that 76.92％ (10/13),15.38％ (2/13) and 7.69 ％ (1/13) of atypical solitary metastatic malignant melanoma were hypointensity,isointensity and hyperintensity respectively.The qualitative evaluation of SIs on T2WI were found that 61.54％ (8/13) of atypical solitary metastatic malignant melanoma with hypointense,30.77％ (4/13) with isointensity and 7.69％ (1/13) with hyperintensity,respectively.About 92.31％ (12/13) of atypical solitary metastatic malignant melanoma displayed strong enhancement on contrast-enhanced imaging.There were significant differences in SIs on T1WI,T2WI and contrast-enhanced imaging between atypical solitary metastatic malignant melanoma and hemangioma (all P＜0.05).The maximum diameter of atypical solitary metastatic malignant melanoma was significantly higher than that of spinal hemangioma (P＜0.001).Conclusion MR imaging would be practicable for differentiation between atypical solitary metastatic malignant melanoma and hemangioma in spine.
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Objective To assess the diagnostic accuracy of multidetector CT (MDCT) for restaging of patients with esophageal squamous cell carcinoma (SCC) after neoadjuvant chemotherapy and determine the feasibility of CT for assessing the treatment response and evaluating the prognosis. Methods Totally 135 patients with esophageal SCC who had received neoadjuvant treatment and surgery in Beijing Cancer Hospital from September 2005 to December 2011 were enrolled in this study. TN staging was performed using CT for lesions before and after neoadjuvant treatment by two radiologists,and the tumor regression grade (TRG) and pathological TRG were also assessed. Based on preoperative CT TN restaging results,the patients were defined as responders with TNafter therapy,non-responders with T3-4N+,and patients with undefined response (TN0 or TNN). Results The accuracy of T and N restaging using CT was 50%,54% (κ=0.718,P <0.001) and 59%,56% (κ=0.753,P <0.001) by two radiologists,respectively. TRG from CT was predicted correctly in 27% of patients. Pathological TRG was an accurate predictor of survival (χ=8.13,P=0.04). There was no significant trend toward better survival for lower CT TRG (χ=1.17,P=0.286). Among 135 patients with esophageal cancer,19 patients(14.07%) were responders ,46 patients(34.07%) were non-responders,and 70 patients (50.37%)were patients with undefined response . The overall survival rates of responders,non-responders and patients with undefined response were 71.5%,47.3%,and 18.5%,respectively. The overall survival of responders was better than that of patients with undefined response (χ=1.518,P=0.63) and non-responders(χ=12.04,P=0.0016),but the overall survival of patients with undefined response was better than that of non-responders (χ=14.468,P=0.0003). Conclusion sMDCT restaging after neoadjuvant treatment can not accurately predict pathological stage in esophageal SCC. The CT T and N restaging has certain clinical value in assessing the response to neoadjuvant chemotherapy in patients with esophageal cancer and predicting the prognosis.