Application of intravoxel incoherent motion diffusion-weighted imaging for preoperative knowledge of lymphovascular invasion in gastric cancer: a prospective study.

PURPOSE: To investigate the potential of intravoxel incoherent motion diffusion-weighted imaging (IVIM) for preoperative prediction of lymphovascular invasion (LVI) in gastric cancer (GC). METHODS: This study prospectively enrolled 90 patients (62 males, 28 females, 60.79 ± 9.99 years old) who received radical gastrostomy. Abdominal MRI examinations including IVIM were performed within 1 week before surgery. Patients were divided into LVI-positive and -negative group according to pathological diagnosis after surgery. The apparent diffusion coefficient (ADC) and IVIM parameters, including true diffusion coefficient (D), pseudodiffusion coefficient (D*), and pseudodiffusion fraction (f), were compared between the two groups. The relationship between MRI parameters and LVI was studied by Spearman's correlation analysis. Multivariable logistic regression analysis was used to screen independent predictors of LVI. Receiver-operating characteristic curve analyses were applied to evaluate the efficacy. RESULTS: The ADC, D in LVI-positive group were lower, whereas tumor thickness and f parameter in LVI-positive group were higher than those in LVI-negative group, and they were statistically correlated with LVI (p < 0.05). D, f and tumor thickness were independent risk factors of LVI. The area under the curve of ADC, D, f, thickness, and the combined parameter (D + f + thickness) were 0.667, 0.754, 0.695, 0.792, and 0.876, respectively. The combined parameter demonstrated higher efficacy than any other parameters (p < 0.05). CONCLUSION: The ADC, D, and f can effectively distinguish LVI status of GC. The D, f and thickness were independent predictors. The combination of the three predictors further improved the efficacy.

Comparison of MRI and CT-Based Radiomics and Their Combination for Early Identification of Pathological Response to Neoadjuvant Chemotherapy in Locally Advanced Gastric Cancer.

BACKGROUND: Current radiomics for treatment response assessment in gastric cancer (GC) have focused solely on Computed tomography (CT). The importance of multi-parametric magnetic resonance imaging (mp-MRI) radiomics in GC is less clear. PURPOSE: To compare and combine CT and mp-MRI radiomics for pretreatment identification of pathological response to neoadjuvant chemotherapy in GC. STUDY TYPE: Retrospective. POPULATION: Two hundred twenty-five GC patients were recruited and split into training (157) and validation dataset (68) in the ratio of 7:3 randomly. FIELD/SEQUENCE: T2-weighted fast spin echo (fat suppressed T2-weighted imaging [fs-T2WI]), diffusion weighted echo planar imaging (DWI), and fast gradient echo (dynamic contrast enhanced [DCE]) sequences at 3.0T. ASSESSMENT: Apparent diffusion coefficient (ADC) maps were generated from DWI. CT, fs-T2WI, ADC, DCE, and mp-MRI Radiomics score (Radscores) were compared between responders and non-responders. A multimodal nomogram combining CT and mp-MRI Radscores was developed. Patients were followed up for 3-65 months (median 19) after surgery, the overall survival (OS) and progression free survival (PFS) were calculated. STATISTICAL TESTS: A logistic regression classifier was applied to construct the five models. Each model's performance was evaluated using a receiver operating characteristic curve. The association of the nomogram with OS/PFS was evaluated by Kaplan-Meier survival analysis and C-index. A P value <0.05 was considered statistically significant. RESULTS: CT Radscore, mp-MRI Radscore and nomogram were significantly associated with tumor regression grading. The nomogram achieved the highest area under the curves (AUCs) of 0.893 (0.834-0.937) and 0.871 (0.767-0.940) in training and validation datasets, respectively. The C-index was 0.589 for OS and 0.601 for PFS. The AUCs of the mp-MRI model were not significantly different to that of the CT model in training (0.831 vs. 0.770, P = 0.267) and validation dataset (0.797 vs. 0.746, P = 0.137). DATA CONCLUSIONS: mp-MRI radiomics provides similar results to CT radiomics for early identification of pathologic response to neoadjuvant chemotherapy. The multimodal radiomics nomogram further improved the capability. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 2.

A retrospective study of thoracic endovascular aortic repair timing in patients with uncomplicated type B dissection who have a smoking history.

Objective: To determine the optimal timing of thoracic endovascular aortic repair (TEVAR) for patients with uncomplicated type B dissections who have a smoking history. Methods: Data from 308 consecutive patients with uncomplicated type B dissections, who have a smoking history and onset-to-TEVAR time within 90 days, were analyzed. The patients were divided into two groups: Acute and subacute phases. Univariate and multivariate regression analyses were performed. Smooth curve fitting and threshold analysis were performed to characterize the relationship between the onset-to-TEVAR time and follow-up deaths. Results: There were no significant differences between the two groups. Smooth curve fitting and threshold effect analysis showed that if early TEVAR was performed within 9.4 days from onset, there was better long-term survival and there was no significant difference after 9.4 days. Conclusion: By studying the relationship between onset-to-TEVAR time and all-cause mortality, we found that early TEVAR may have a lower all-cause mortality rate during follow-up in uncomplicated type B dissection patients who have a smoking history and within 90 days from onset.

Dynamic contrast-enhanced and diffusion-weighted MR imaging in early prediction of pathologic response to neoadjuvant chemotherapy in locally advanced gastric cancer.

PURPOSE: To investigate the efficacy of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for the early prediction of the pathologic response to neoadjuvant chemotherapy (NAC) in patients with locally advanced gastric cancer (LAGC). METHODS: Fifty patients with LAGC who were treated with NAC followed by radical gastrectomy were enrolled. Uncontrasted and DCE-MRI were performed within 1 week before NAC. According to tumor regression grading (TRG), patients were labeled as responders (TRG = 0 + 1) and non-responders (TRG = 2 + 3). Apparent diffusion coefficients (ADC) and DCE-MRI kinetics (Ktrans, Ve, and Kep) were compared between the two groups. Logistic regression analysis was performed to screen independent factors to predict the NAC efficacy. The relationship between MRI parameters and TRG was studied by Spearman's correlation analysis. Receiver-operating characteristic curve analyses were applied to evaluate the efficacy. RESULTS: ADC, Ktrans, and Kep values were higher in responders than in non-responders (p < 0.05) and correlated with TRG (p < 0.05). The ADC and Kep values were independent markers for predicting TRG. The area under the curve, sensitivities, specificities of ADC, Ktrans, Kep, and ADC + Kep were 0.813, 0.699, 0.709, 0.886;73.64%, 65.54%, 63.21%, 70.37%; 86.47%, 54.97%, 79.47%, 95.65%; respectively. ADC + Kep demonstrated a higher efficacy than Ktrans and Kep (p = 0.012, 0.011), but without improvement compared with ADC (p > 0.05). CONCLUSION: Both DWI and DCE-MRI can effectively predict the pathologic response to NAC in LAGC. A combination of ADC and Kep increased the efficacy, and ADC is the most valuable imaging parameter.

Thoracic endovascular aortic repair (TEVAR) to retrieve a stented elephant trunk graft entrapped in the false lumen of dissection patients.

A stented elephant trunk graft entrapped in the false lumen during Sun's procedure (total arch replacement combined with stented elephant trunk implantation) is a serious complication with an extremely high mortality rate. This article describes a case of a patient who was successfully saved with the use of thoracic endovascular aortic repair.

Predicting Parametrial Invasion in Cervical Carcinoma (Stages IB1, IB2, and IIA): Diagnostic Accuracy of T2-Weighted Imaging Combined With DWI at 3 T.

OBJECTIVE: The objective of our study was to retrospectively evaluate the efficacy of combined analysis of T2-weighted imaging and DWI in the diagnosis of parametrial invasion (PMI) in cervical carcinoma. MATERIALS AND METHODS: The clinical records of 192 patients with cervical carcinoma who met the study requirements were reviewed for this retrospective study. The signal intensities of suspicious PMI tissue were assessed on T2-weighted images, DW images, and apparent diffusion coefficient maps independently by two experienced radiologists. The radiologist observers predicted the presence of PMI by scoring T2-weighted imaging alone and then by scoring T2-weighted imaging and DWI combined. The results were compared with histopathologic findings. RESULTS: Histopathologic findings revealed PMI in 24 of 192 study subjects. In positively predicting the presence of PMI, T2-weighted imaging and DWI combined scored significantly better than T2-weighted imaging alone, as proven by high sensitivity (T2-weighted imaging alone vs T2-weighted imaging and DWI combined: observer 1, 75.0% vs 83.3% [p = 0.477]; observer 2, 66.7% vs 91.7% [p < 0.05]), high specificity (T2-weighted imaging alone vs T2-weighted imaging and DWI combined: observer 1, 84.5% vs 98.8% [p < 0.001]; observer 2, 85.7% vs 98.8% [p < 0.001]), and high accuracy (T2-weighted imaging alone vs T2-weighted imaging and DWI combined: observer 1, 83.3% vs 96.9% [p < 0.001]; observer 2, 83.3% vs 97.9% [p < 0.001]). The area under the ROC curve was also significantly higher for T2-weighted imaging and DWI combined (observer 1, 0.911; observer 2, 0.952) than for T2-weighted imaging alone (observer 1, 0.798; observer 2, 0.762). Although the interobserver agreement was good for T2-weighted imaging (κ = 0.695) and excellent for T2-weighted imaging and DWI combined (κ = 0.753), the improvement failed to achieve statistical significance (p = 0.28). CONCLUSION: Combined analysis of T2-weighted imaging and DWI enhances the accuracy of diagnosing PMI in patients with cervical cancer compared with T2-weighted imaging alone.

Research Advances in the Role of RAS-GTPase-activating Proteins in Tumors.

A variety of molecules are involved in tumorigenesis,during which the RAS pathway-related molecules play key roles. RAS gene mutations exist in about 30% of human tumors;in some tumors(e.g. pancreatic adenocarcinomas),the mutation rates may rise to 75%-95%. Even in tumors without RAS mutations,the RAS pathway-related molecules can also be highly activated. RAS-GTPase-activating proteins(RASGAPs)are a group of tumor suppressors. They normally turn off RAS pathway by catalyzing the hydrolysis of RAS-GTP. However,the mutation or hypermethylation of their promoters will inactivate their roles and thus provide an alternative mechanism of activating Ras. This article reviews the research advances in the role of RASGAPs in the development of tumors.

Effect of intravenous gadolinium-DTPA on diffusion-weighted imaging of brain tumors: a short temporal interval assessment.

PURPOSE: To determine the effect of intravenous administration of gadolinium (Gd) contrast medium (Gd-DTPA) on diffusion-weighted imaging (DWI) for the evaluation of normal brain parenchyma vs. brain tumor following a short temporal interval. MATERIALS AND METHODS: Forty-four DWI studies using b values of 0 and 1000 s/mm(2) were performed before, immediately after, 1 min after, 3 min after, and 5 min after the administration of Gd-DTPA on 62 separate lesions including 15 meningioma, 17 glioma and 30 metastatic lesions. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and apparent diffusion coefficient (ADC) values of the brain tumor lesions and normal brain tissues were measured on pre- and postcontrast images. Statistical analysis using paired t-test between precontrast and postcontrast data were obtained on three brain tumors and normal brain tissue. RESULTS: The SNR and CNR of brain tumors and the SNR of normal brain tissue showed no statistical differences between pre- and postcontrast (P > 0.05). The ADC values on the three cases of brain tumors demonstrated significant initial increase on the immediate time point (P < 0.01) and decrease on following the 1 min time point (P < 0.01) after contrast. Significant decrease of ADC value was still found at 3min and 5min time point in the meningioma group (P < 0.01) with gradual normalization over time. The ADC values of normal brain tissues demonstrated significant initial elevation on the immediately postcontrast DWI sequence (P < 0.01). CONCLUSION: Contrast medium can cause a slight but statistically significant change on the ADC value within a short temporal interval after the contrast administration. The effect is both time and lesion-type dependent.

Comparison of computed tomography versus magnetic resonance imaging in assessing radiofrequency ablation margins after radiofrequency ablation in patients with hepatocellular carcinomas.

OBJECTIVE: To assess the diagnostic value of magnetic resonance imaging (MRI) in the follow-up of patients with hepatocellular carcinomas treated with radiofrequency ablation (RFA) and to compare it with that of computed tomography (CT). METHODS: From December 2009 to September 2011, 40 patients (47 hepatocellular carcinomas) were treated with RFA after transcatheter arterial chemoembolization and underwent MRI and CT for follow-up. RFA margins were assessed on a five-point scale with receiver operating characteristic curve analysis. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were evaluated. RESULTS: The interobserver agreement rate for MRI was significantly higher (Kappa=0.935) than for CT (Kappa=0.714; P < 0.05). The scores of 1 and 5 points for MRI, which confirms the presence or absence of residual tumor, accounted for 89.4% (84/94), while for CT accounting for only 31.9% (30/94). The area under the receiver operating characteristic curve of MRI was significantly higher than that of CT (P < 0.05), as were the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of detection rate (mean, 100%, 96.4%, 76.9%, 100%, and 96.8% for MRI, respectively, vs. 30.0%, 57.1%, 10.3%, 87.7%, and 63.8% for CT). CONCLUSION: MRI is superior to CT in assessing the RFA margins in terms of the diagnostic accuracy and detection rate .

Atypical polypoid adenomyomas progressed to endometrial endometrioid adenocarcinomas.

INTRODUCTION: Atypical polypoid adenomyoma (APA) is an uncommon uterine tumor which is composed of atypical endometrial glands and cellular smooth-muscle stroma. At present APA is categorized as a benign lesion and treated conservatively in the literatures. However, there are also several cases reported that progressed to endometrial endometrioid adenocarcinoma (EEC) till now. Here, we present two more rare cases of APA that may have undergone progression to EEC. MATERIALS: Two patients who had APA 6 and 4 years ago, respectively, and had ECC were reported. METHODS: The history of the two patients and the literatures were retrospectively reviewed. CONCLUSIONS: The truth that APA may have a chance to progress to carcinoma suggests that APA is at least an indicator lesion for the development of EEC, and highlights that clinicians should carefully monitor the patients, and a meticulous follow-up examination is mandatory.

Is severe dysplasia the same lesion as carcinoma in situ? 10-Year follow-up of laryngeal precancerous lesions.

CONCLUSION: Our results showed that the behavior of moderate dysplasia lesions was more like that of severe dysplasia lesions, while severe dysplasia was very different from carcinoma in situ (CIS). CIS should be managed more aggressively than the other lesions. Mild dysplasia could not be viewed as a precancerous lesion of the larynx. OBJECTIVE: This study aimed to identify the possibilities of the precancerous lesions of larynx (including mild dysplasia, moderate dysplasia, severe dysplasia, and CIS) progressing to invasive carcinomas and to highlight the importance of adequate management and follow-up strategies for these patients. METHODS: A retrospective study of patients who had these preinvasive lesions in the larynx over a 10-year period was performed. RESULTS: These patients were followed for a minimum period of 2 years from the initial diagnosis. In all, 86 patients were identified the cohort. Of these, 17 (19.8%) patients developed carcinoma: 0 of 22 with mild dysplasia, 5 of 25 (20%) with moderate dysplasia, 2 of 14 (15%) with severe dysplasia, and 10 of 25 (40%) patients with CIS progressed to invasive cancers (p = 0.001). Over 50% of cases progressed 3 years after the original biopsy. Only 1 of 86 (1%) died of the disease.

Squamous cell carcinoma in the larynx in a 7-year-child.

Squamous cell carcinoma (SCC) involving the larynx in childhood is very rare, especially in the ages younger than 10 years. Most of the reported cases are transformed from the recurrent respiratory papillomatosis (RRP) with human papilloma virus (HPV) infection. Due to the RRP long course, the rarity and the unspecific symptoms of the cancer, they usually are diagnosed at late stages. Controversy exists regarding the causes and the treatments of these kinds of diseases. Here, we reviewed the related reports and presented a case of 7-year-old boy who had an advanced well-differentiated SCC of the larynx which transformed from RRP with HPV genotyping test negative. The patient underwent only the resection of involved tissues and no other treatments. Except for hoarseness in his voice, the boy is going well and has had an uneventful course of 10 years following operative treatment.

Expression of mucins and E-cadherin in gastric carcinoma and their clinical significance.

AIM: To investigate the expression of three types of mucin (MUC1, MUC2, MUC5AC) and E-cadherin in human gastric carcinomas and their clinical significance. METHODS: Ninety-four gastric cancer specimens were classified according to WHO criteria and detected by immunohistochemical assay of expression of mucins and E-cadherin. RESULTS: The positive expression rates of MUC1, MUC2, MUC5AC and E-cadherin were 82% (77/94), 84% (79/94), 40% (38/94) and 56% (53/94) respectively. MUC1 expression was significantly correlated with the types of cancer (the positive rates of MUC1 in well and moderately differentiated tubular adenocarcinoma, poorly differentiated adenocarcinoma, signet-ring cell carcinoma and mucinous carcinoma were 91%, 87%, 71%, 71%, respectively, P<0.05), age of patients (the positive rates of it among the people who are younger than 40 years, between 40-60 years and over 60 year were 74%, 81%, 89%, P<0.05), lymph nodes involvement (the positive rates in the non-interfered group and the interfered group were 78%, 85%, P<0.05) and tumor size (the positive rates in the tumors with the size less than 3 cm, 3-6 cm and larger than 6 cm were 69%, 92%, 69%, P<0.05); MUC2 expression was significantly associated with types of cancers and had the strongest expression in mucinous carcinomas(the positive rates of MUC2 in well and moderately differentiated tubular adenocarcinoma, poorly differentiated adenocarcinoma, signet-ring cell carcinoma and mucinous carcinoma were 94%, 70%, 81%, 100%, P<0.05), but it had no obvious relation to age, gender, tumor location, lymph nodes involvement, depth of invasion and metastasis to extra-gastric organs (P>0.05); MUC5AC expression was not related to any of the characteristics investigated except that it had relation to gender, whereas MUC5AC showed the tendency to higher expression in less invasive lesions and lower expression in advanced stage cancers (P>0.05); No significant difference was found for E-cadherin expression. There were strong positive relationships between the expression of MUC1 and E-cadherin, MUC2 and E-cadherin, MUC1 and MUC2 (R = 0.33, R = 0.22, R = 0.32, respectively, P<0.05). According to the COX proportional hazards model, older patients, involvement of lymph nodes, different types of gastric cancer and MUC2 expression were significantly associated with poorer outcome of gastric carcinoma patients (beta = 0.08, beta = 3.94, beta = 1.33, beta = 0.75, respectively, P<0.05). CONCLUSION: MUC1 and MUC2 are good markers of different types of gastric cancer. MUC2 is especially a good marker of mucinous carcinoma. MUC1, MUC2 may interfere with the function of E-cadherin in gastric carcinomas, and have synergic effect on progression of gastric cancers.