Yi Wang

Discrimination of metastatic lymph nodes in patients with gastric carcinoma using diffusion‐weighted imaging

To determine the accuracy of diffusion‐weighted imaging (DWI) in discrimination of metastatic lymph nodes (LNs) in gastric carcinoma with rigorous histopathological correlation.

Carcinosarcoma of pancreas with liver metastasis combined with gastrointestinal stromal tumour of the stomach: is there a good prognosis with the complete resection?

We report a carcinosarcoma of the pancreas with liver metastasis combined with gastrointestinal stromal tumour (GIST) of the stomach in a 72-year-old woman who presented with right upper quadrant pain, nausea and vomiting. A radical resection including pancreaticoduodenectomy, left hepatic lobe resection and local resection of the gastric mass was performed. The tumour in the head of pancreas was found to be grossly yellow-white, and it infiltrated the common bile duct and duodenum; the mass of the liver metastasis is solitary. Pathologic examination showed two components separated from each other: one component was a conventional infiltrating pancreatic ductal adenocarcinoma, and the other component showed sarcomatous growth pattern composed of pleomorphic spindle cells. The neoplasm of the stomach was confirmed a low malignant potential GIST by histology and immunohistochemistry. The patient was obliged to be in hospital because of abnormal bowel function; moreover, surveillance CT scans performed at 1.5 months post-operatively showed multiple liver metastasis and recurrence in the tail of pancreas. Unfortunately, the patient died of multiple organ failure at 2 months post-operatively. To our knowledge, this is the first experience report about surgical treatment of carcinosarcoma of pancreas with liver metastasis combined with GIST of the stomach. The patient performed a radical surgery for the metastatic carcinosarcoma even if that could be resected completely did not have a good consequence.

Delayed hyperenhancement patterns in occlusive and reperfused myocardial infarcts during different healing stages.

To investigate delayed hyperenhancement during different healing stages of myocardial infarct with and without reperfusion in a pig model.

The prognostic significance of extramural venous invasion detected by multiple-row detector computed tomography in stage III gastric cancer

PurposeTo determine the 1-year progression-free survival (PFS) of extramural venous invasion (EMVI), detected with contrast-enhanced multiple-row detector computed tomography (ceMDCT), in patients with stagexa0IIIxa0gastric cancer.MethodsBetween January 2009 and December 2013, 117 patients with pathological-proved stagexa0IIIxa0gastric cancer based on the criteria of the AJCC 7th were included in this retrospective study. All patients underwent adjuvant chemotherapy postoperatively and had been monitored with the follow-up chest/abdomen/pelvis ceMDCT on 3, 6, and 12xa0months post-operation. Two radiologists reviewed preoperative images regarding the presence of EMVI, categories of tumor and categories of lymph node. Conventional prognostic histological factors including pathological T/N status, tumor location/growth pattern, histological type/tumor differentiation, and tumor size were also recorded. Disease progression was defined as the presence of radiological or/and pathology-confirmed metachronous metastases, local recurrence, or gastric cancer-related death. The 1-year PFS for both EMVI-positive and EMVI-negative was calculated using the Kaplan–Meier product limit. Hazard ratios for 1-year PFS were generated using a Cox proportional hazard regression on ceMDCT tumor characteristics.ResultsThe prevalence of EMVI detected with ceMDCT was 43.6% (51/117) in patients with stagexa0IIIxa0gastric cancer. The EMVI-positive patients had significantly lower 1-year PFS rates (45.1%), than the EMVI-negative patients (75.8%), (Log-rank test, Pxa0=xa00.0008). In a Cox proportional hazards regression analysis, EMVI and tumor location/growth pattern were identified as independent prognostic factors of 1-year PFS with hazard ratio of 2.272 (95% CI 1.133–4.556, Pxa0=xa00.021) and 1.982 (95% CI 1.040–3.780, Pxa0=xa00.039), respectively.ConclusionEMVI status, detected with ceMDCT, could be used to counsel patients regarding ongoing risks of metastatic disease, implications for surveillance, and systemic chemotherapy.

The Therapeutic Response of Gastrointestinal Stromal Tumors to Imatinib Treatment Assessed by Intravoxel Incoherent Motion Diffusion-Weighted Magnetic Resonance Imaging with Histopathological Correlation.

Purpose To exploit the intravoxel incoherent motion (IVIM) diffusion-weighted (DW) MRI when evaluating the therapeutic response of gastrointestinal stromal tumors (GIST) to Imatinib in a mouse model. Materials and Methods Mice with xenografts bearing cells from the GIST-T1 cell line were randomly divided into a treated group receiving Imatinib and a control group. DWMRI scans with 14 b-values (0–1500 s/mm2) were performed before and after treatment (days 1, 3 and 7). IVIM related parameters perfusion fractions (fp) and perfusion-related diffusion coefficients (D*) and the conventional apparent diffusion coefficients (ADC) were calculated by fitting the DWMRI signal decay. The mean changes from baseline to each post-treatment time point for each measurement (ΔADC, Δfp and ΔD*) were calculated. The differences of mean changes between the two groups were tested for statistical significance. Histopathological analyses including Ki-67, CD31, TUNEL and H&E were conducted in conjunction with the MRI scans. Results Increases in ADC of the treated group were higher than those of the control group after treatment, whereas statistical significances were not observed. Compared to the control group, D* in the treated group decreased significantly (ΔD*treated = -41%, -49%, and -49% with P = 0.0001, 0.0001 and 0.0001), and fp increased significantly (Δfptreated = 79%, 82% and 110%, with P = 0.001, 0.0001 and P = 0.0007) on days 1, 3 and 7 after treatment. Histopathological analyses demonstrated different tumor tissue characteristics between the treated and control groups. Conclusion IVIM measurements may serve as more sensitive imaging biomarkers than ADC when assessing GIST response to Imatinib as early as one day after treatment.

Chemotherapy response evaluation in a mouse model of gastric cancer using intravoxel incoherent motion diffusion-weighted MRI and histopathology

AIM To determine the role of intravoxel incoherent motion (IVIM) diffusion-weighted (DW) magnetic resonance imaging (MRI) using a bi-exponential model in chemotherapy response evaluation in a gastric cancer mouse model. METHODS Mice bearing MKN-45 human gastric adenocarcinoma xenografts were divided into four treated groups (TG1, 2, 3 and 4, n = 5 in each group) which received Fluorouracil and Calcium Folinate and a control group (CG, n = 7). DW-MRI scans with 14 b-values (0-1500 s/mm2) were performed before and after treatment on days 3, 7, 14 and 21. Fast diffusion component (presumably pseudo-perfusion) parameters including the fast diffusion coefficient (D*) and fraction volume (fp), slow diffusion coefficient (D) and the conventional apparent diffusion coefficients (ADC) were calculated by fitting the IVIM model to the measured DW signals. The median changes from the baseline to each post-treatment time point for each measurement (ΔADC, ΔD* and Δfp) were calculated. The differences in the median changes between the two groups were compared using the mixed linear regression model by the restricted maximum likelihood method shown as z values. Histopathological analyses including Ki-67, CD31, TUNEL and H&E were conducted in conjunction with the MRI scans. The median percentage changes were compared with the histopathological analyses between the pre- and post-treatment for each measurement. RESULTS Compared with the control group, D* in the treated group decreased significantly (ΔD*treated% = -30%, -34% and -20%, with z = -5.40, -4.18 and -1.95. P = 0.0001, 0.0001 and 0.0244) and fp increased significantly (Δfptreated% = 93%, 113% and 181%, with z = 4.63, 5.52, and 2.12, P = 0.001, 0.0001 and 0.0336) on day 3, 7 and 14, respectively. Increases in ADC in the treated group were higher than those in the control group on days 3 and 14 (z = 2.44 and 2.40, P = 0.0147 and P = 0.0164). CONCLUSION Fast diffusion measurements derived from the bi-exponential IVIM model may be more sensitive imaging biomarkers than ADC to assess chemotherapy response in gastric adenocarcinoma.

Extramural venous invasion detected by MDCT as an adverse imaging feature for predicting synchronous metastases in T4 gastric cancer.

Background Extramural venous invasion (EMVI) is defined histologically as the active invasion of tumor cells to the lumens of mesenteric vessels beyond the muscularis propria in advanced gastrointestinal cancer, resulting in distant metastases. Purpose To determine the association between synchronous metastatic disease in patients with T4 gastric cancer and EMVI detected on contrast-enhanced multiple-row detector computed tomography (MDCT). Material and Methods A total of 152 patients with T4 gastric carcinoma were retrospectively reviewed and divided into EMVI-positive and EMVI-negative groups where EMVI, as detected on MDCT, was defined as a tubular or nodular soft tissue thickening extending from the tumor along the vessels of the mesentery. Synchronous metastases were detected by MDCT and/or confirmed by postoperative diagnosis. Logistic regression analyses were performed to analyze the predictive factors of synchronous metastases in gastric cancer. Results Synchronous metastases were found in 47 of 152 (30.9%) patients with T4 gastric cancer. Thirty-one of 77 (40.3%) patients in the EMVI-positive group had evidence of metastases compared to 16 (21.3%) of 75 patients in the EMVI-negative group (Pu2009=u20090.019). Synchronous metastases were significantly associated with EMVI with an odds ratio (OR) of 2.250 (95% CI, 1.072–4.724). Conclusion EMVI-positive tumors, as an adverse imaging feature, were significantly associated with synchronous metastases in patients with T4 gastric cancer.

Low- Versus High-Risk Rectal Cancer Based on MRI Features: Outcomes in Patients Treated Without Neoadjuvant Chemoradiotherapy

OBJECTIVEnThe objective of this study was to compare the prognoses of patients with low- and high-risk rectal cancer detected by MRI who were treated without neoadjuvant chemoradiotherapy (NCRT) and to determine independent risk factors.nnnMATERIALS AND METHODSnThis retrospective study included 185 patients with pathologically proven rectal adenocarcinoma who were treated without NCRT. Cancer was defined as high risk if one or more of the following factors were present: extramural depth of tumor invasion greater than 5 mm or stage T4a or T4b for tumor in the mid or high rectum; involvement of intersphincteric space, levators, or adjacent organs for tumor in the low rectum; extramural venous invasion (EMVI); or circumferential resection margin (CRM) involvement. Patients without any of those risk factors were placed in the low-risk group. The Kaplan-Meier method and Cox proportional hazards regression model were used to compare the survival outcomes between the two groups and to investigate the univariate and multivariate influences of the risk factors.nnnRESULTSnCancer was deemed to be low risk in 65 (35.1%) patients and high risk in 120 (64.9%) patients. The two patient groups had statistically significant differences in 3-year actuarial overall survival (OS; 100% vs 88.3%, p = 0.0044), disease-free survival (DFS; 92.3% vs 60.0%, p < 0.0001), and local recurrence (LR; 1.5% vs 10.0%, p = 0.0297). CRM involvement was identified as an independent risk factor for OS (hazard ratio [HR], 4.78; 95% CI, 1.24-18.45), DFS (HR, 2.44; 95% CI, 1.24-4.81), and LR (HR, 3.92; 95% CI, 1.07-14.41). Moreover, EMVI was identified as an independent risk factor for DFS (HR, 2.46; 95% CI, 1.28-4.74).nnnCONCLUSIONnThe LR and long-term survival of patients in the low-risk group were more favorable than those of patients in the high-risk group. EMVI and CRM status were independent risk factors.

Extramural vascular invasion detected by contrast-enhanced multiple-row detectors computed tomography (ceMDCT) as a predictor of synchronous metastases in colon cancer

Background Extramural Vascular Invasion (EMVI) is histologically defined as the presence of tumor cells beyond the muscularis propria in vessels resulting in disease metastases. Objective To determine whether EMVI, detected by contrast-enhanced multiple-row detectors computed tomography (MDCT), has closely association with synchronous metastases in colon cancer. Methods Patients with pathology proven colon cancer were included in this retrospective study. Preoperative imaging status, including Extramural tumor depth, Lymph nodes, tumor location, and ctEMVI status, were defined on MDCT. Postoperative pathological tumor stage, lymph node stage, and tumor differentiation, were defined in accordance with the American Joint Committee on Cancer (AJCC) 7th Edition. Synchronous metastases were detected on follow-up MDCT 3 months after initial diagnosis or by surgery, if available. Associations between ctEMVI and other preoperative and postoperative factors were analyzed using Chi-squared tests. Logistic regression analyses were performed to analyze the preoperative and postoperative factors of synchronous metastases in colon cancer. Results ctEMVI was observed in 96 patients (96/241, 39.8%). The presence of ctEMVI varied significantly depending on ctEMD (χ2 = 66.557, P<0.001), lymph nodes status on MDCT (χ2 =24.533, P=0.001), pathological tumor status (χ2 = 36.267, P <0.001) and pathological lymph nodes status analyses (χ2 =32.103, P <0.001). Synchronous metastases were seen in 36 patients (36/96, 37.5%) with ctEMVI and 11 (11/145, 7.6%) patients without ctEMVI. The incidence of synchronous metastases was significantly higher in the cohort of positive ctEMVI with odds ratio (OR) of 7.309 (95% CI 3.485∼15.330, P<0.001). Positive ctEMVI (Odds ratio 4.654, 95%CI: 1.987∼10.898, P <0.001) and ctEMD larger than 5 mm (Odds ratio 2.654, 95%CI: 1.116∼6.309, P =0.027) were demonstrated to be significant preoperative factors in predicting synchronous metastases. Conclusion MDCT-detected EMVI could be used as a preoperative factor to predict synchronous metastases in colon cancer.

Prognostic significance of computed tomography-detected extramural vascular invasion in colon cancer

AIMnTo compare disease-free survival (DFS) between extramural vascular invasion (EMVI)-positive and -negative colon cancer patients evaluated by computed tomography (CT).nnnMETHODSnColon cancer patients (n = 194) undergoing curative surgery between January 2009 and December 2013 were included. Each patients demographics, cancer characteristics, EMVI status, pathological status and survival outcomes were recorded. All included patients had been routinely monitored until December 2015. EMVI was defined as tumor tissue within adjacent vessels beyond the colon wall as seen on enhanced CT. Disease recurrence was defined as metachronous metastases, local recurrence, or death due to colon cancer. Kaplan-Meier analyses were used to compare DFS between the EMVI-positive and -negative groups. Coxs proportional hazards models were used to measure the impact of confounding variables on survival rates.nnnRESULTSnEMVI was observed on CT (ctEMVI) in 60 patients (30.9%, 60/194). One year after surgery, there was no statistically significant difference regarding the rates of progressive events between EMVI-positive and -negative patients [11.7% (7/60) and 6.7% (9/134), respectively; P = 0.266]. At the study endpoint, the EMVI-positive patients had significantly more progressive events than the EMVI-negative patients [43.3% (26/60) and 14.9% (20/134), respectively; odds ratio = 4.4, P < 0.001]. Based on the Kaplan-Meier method, the cumulative 1-year DFS rates were 86.7% (95%CI: 82.3-91.1) and 92.4% (95%CI: 90.1-94.7) for EMVI-positive and EMVI-negative patients, respectively. The cumulative 3-year DFS rates were 49.5% (95%CI: 42.1-56.9) and 85.8% (95%CI: 82.6-89.0), respectively. Cox proportional hazards regression analysis revealed that ctEMVI was an independent predictor of DFS with a hazard ratio of 2.15 (95%CI: 1.12-4.14, P = 0.023).nnnCONCLUSIONnctEMVI may be helpful when evaluating disease progression in colon cancer patients.