Extramural venous invasion by gastrointestinal malignancies: CT appearances

CT-based scores for extramural vascular invasion and occult peritoneal metastasis correlate with gastric cancer survival

OBJECTIVE

To assess the feasibility of scoring extragastric vascular invasion and occult peritoneal metastasis using preoperative computed tomography (CT) images of gastric cancer (GC) and to explore the correlation between these scores and patient prognosis.

METHODS

587 GC patients with CT scans from two centers, all confirmed by pathology, were retrospectively evaluated. Scores for CT-detected blood vessel invasion (ctBVI), lymphatic invasion (ctLVI), and occult peritoneal metastasis (ctOPM) were assigned based on preoperative CT images. The patients' follow-up provided data on overall and disease-free survival. Cox proportional hazard models were used to analyze prognostic factors.

RESULTS

The inter-group and intra-group consistency of ctBVL, ctLVI, and ctOPM scores were all > 0.70. Log-rank analysis demonstrated a statistically significant difference in survival curves (p < 0.001). CtBVL, ctLVI, and ctOPM scores were related to overall survival (OS) and disease-free survival (DFS). Univariate and multivariate Cox regression analyses identified ctBVL, ctLVI, ctOPM scores as independent risk factors for GC prognosis. In multivariate analysis, the three sign scores were related to DFS (p < 0.05), with ctBVL (hazard ratio (HR) = 1.980, 95% CI: 1.336-2.933), ctLVI (HR = 1.502, 95% CI: 1.336-2.933), and ctOPM (HR = 1.182, 95% CI: 0.886-1.578). The three scores were also correlated with OS (p < 0.05), ctBVL (HR = 2.003, 95% CI: 1.278-3.139), ctLVI (HR = 1.523, 95% CI:1.055-2.200) and ctOPM (HR = 1.289, 95% CI: 1.013-1.770).

CONCLUSION

CtBVL, ctLVI, and ctOPM scores are valuable prognostic indicators in gastric cancer, influencing both OS and DFS.

KEY POINTS

Question To study whether the ctBVL, ctLVI, and ctOPM scores assessed by preoperative enhanced CT imaging can predict the survival outcomes of patients. Findings CtBVL, ctLVI, and ctOPM scores, assessed via preoperative enhanced CT imaging, are associated with worse survival outcomes when elevated. Clinical relevance CtBVL, ctLVI, and ctOPM scores may help guide personalized follow-up plans. Patients with higher scores might require closer monitoring and more aggressive treatment.

Dual-phase contrast-enhanced CT-based intratumoral and peritumoral radiomics for preoperative prediction of lymph node metastasis in gastric cancer

OBJECTIVE

To determine whether intratumoral and peritumoral radiomics derived from dual-phase contrast-enhanced CT imaging could predict lymph node metastasis (LNM) in gastric cancer.

METHODS

Patients with gastric cancer from January 2017 to January 2022 were retrospectively collected and were randomly divided into training cohort (n = 287) and test cohort (n = 121) with a ratio of 7: 3. Clinical features and traditional radiological features were analyzed to construct clinical model. Radiomics features based on intratumoral (ITV) and peritumoral volumetric (PTV) regions of the tumor were extracted and screened to construct radiomics models. Clinical-radiomics combined model was constructed by the most predictive radiomics features and clinical independent predictors. The correlation between LNM predicted by the best model and 2-year disease-free survival (DFS) was evaluated by the Kaplan-Meier analysis.

RESULTS

CT-LNM and CT-T stage were independent predictors of LNM. Compared with other radiomics models, ITV + PTV on atrial and venous phase (ITV + PTV-AP + VP) radiomics model presented moderate AUCs of 0.679 and 0.670 in the training cohort and validation cohort, respectively. Among the models, clinical-radiomics combined model achieved the highest AUC of 0.894 and 0.872 in the training and test cohorts, and 0.744 and 0.784 in the T1-2 and T3-4 subgroups, respectively. Clinical-radiomics combined model based LNM could stratify patients into high-risk and low-risk groups, and 2-year DFS of high-risk group was significantly lower than that of low-risk group (p < 0.001).

CONCLUSION

Clinical-radiomics combined model integrating CT-LNM, CT-T stage, and ITV-PTV-AP + VP radiomics features could predict LNM, and this combined model based LNM was associated with 2-year DFS.

Role of Computed Tomography in Predicting Programmed Death Ligand-1 Positivity in Gastric Adenocarcinoma

Objective

To examine the association between computed tomography (CT) imaging characteristics and programmed death ligand-1 (PD-L1) expression in patients with gastric adenocarcinoma (GAC), and to develop a nomogram model for prediction.

Methods

The patients were randomly allocated into a training set and a validation set at a ratio of 7:3. The training set was further divided into a PD-L1 positive group and a PD-L1 negative group, based on the combined positive score (CPS). Univariate and multivariate logistic regression analyses were performed to identify independent predictors of PD-L1 positivity. A nomogram was developed to assess the model's predictive performance, which was evaluated using the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA). It was also compared with the model established by previous study.

Results

Patients with PD-L1-positive gastric adenocarcinoma exhibited a higher prevalence of larger short diameters of lymph nodes (LNs) (≥ 1 cm), and lower CT attenuation values in the venous and delayed phases compared to those in the PD-L1-negative group. Short diameter of LNs, and CT attenuation values in the delayed phase were identified as independent predictors of PD-L1 positivity. The nomogram analysis indicated that CT attenuation values in the delayed phase were the most significant predictor of PD-L1 positivity, followed by short diameter of LNs.

Conclusion

The GAC prediction model based on the CT imaging features is effective in predicting PD-L1 expression levels and demonstrates strong clinical applicability.

Prevalence of CT-detected extramural vascular invasion in gastric adenocarcinoma and its correlation with other known prognostic factors

PURPOSE

To study the prevalence of extramural vascular invasion (EMVI) in patients with gastric adenocarcinoma (GA) and its association with other prognostic factors.

MATERIALS AND METHODS

In this retrospective study, consecutive patients with GA who underwent staging CT between January 2021 and December 2022 were included. Two radiologists reviewed the staging CT for EMVI and its grade and documented tumor location, thickness, and TNM stage. Grade 3 and 4 EMVI were reported as ct-EMVI positive and the rest as negative. Similar findings were documented on restaging CT following neoadjuvant chemotherapy (NAC) when available. ct-EMVI was compared with imaging findings on staging and restaging CT, staging laparoscopy findings, peritoneal fluid cytology, and surgical histopathology findings.

RESULTS

A total of 191 patients (140 males, 51 females) with a mean age of 53 ± 9 years (range 23-93 years) were included. 82.2% had poorly differentiated GA and 17.8% had well/moderately differentiated GA. The majority (95.9%) had T3 (n = 34) and T4 (n = 118) disease on baseline CT. The prevalence of ct-EMVI on staging CT was 65% (n = 124), and 34% and 86% among the T3 and T4 GA, respectively. There was a significant association between ct-EMVI and, tumor thickness, tumor extent, ct-T, N, M stages, and especially peritoneal, lymph nodes, and liver metastases and response to NAC (p < 0.05).

CONCLUSION

EMVI is seen commonly in staging CT of advanced gastric cancer patients and is significantly associated with TNM stage, peritoneal metastases, and response to neoadjuvant chemotherapy. Thus, ct-EMVI is a significant prognostic imaging biomarker in GA. IRB min no: 15713.

The Peritoneum: Anatomy, Pathologic Findings, and Patterns of Disease Spread

Disease spread in the abdomen and pelvis generally occurs in a predictable pattern in relation to anatomic landmarks and fascial planes. Anatomically, the abdominopelvic cavity is subdivided into several smaller spaces or compartments by key ligaments and fascial planes. The abdominal cavity has been traditionally divided into peritoneal, retroperitoneal, and pelvic extraperitoneal spaces. Recently, more clinically relevant classifications have evolved. Many pathologic conditions affect the abdominal cavity, including traumatic, inflammatory, infectious, and neoplastic processes. These abnormalities can extend beyond their sites of origin through various pathways. Identifying the origin of a disease process is the first step in formulating a differential diagnosis and ultimately reaching a final diagnosis. Pathologic conditions differ in terms of pathways of disease spread. For example, simple fluid tracks along fascial planes, respecting anatomic boundaries, while fluid from acute necrotizing pancreatitis can destroy fascial planes, resulting in transfascial spread without regard for anatomic landmarks. Furthermore, neoplastic processes can spread through multiple pathways, with a propensity for spread to noncontiguous sites. When the origin of a disease process is not readily apparent, recognizing the spread pattern can allow the radiologist to work backward and ultimately arrive at the site or source of pathogenesis. As such, a cohesive understanding of the peritoneal anatomy, the typical organ or site of origin for a disease process, and the corresponding pattern of disease spread is critical not only for initial diagnosis but also for establishing a road map for staging, anticipating further disease spread, guiding search patterns and report checklists, determining prognosis, and tailoring appropriate follow-up imaging studies. ©RSNA, 2024 Supplemental material is available for this article.

Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning

BACKGROUND

Lymphovascular invasion (LVI) and perineural invasion (PNI) are important prognostic factors for gastric cancer (GC) that indicate an increased risk of metastasis and poor outcomes. Accurate preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment decisions. However, prior models using conventional computed tomography (CT) images to predict LVI or PNI separately have had limited accuracy. Spectral CT provides quantitative enhancement parameters that may better capture tumor invasion. We hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC patients.

AIM

To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status accurately.

METHODS

This study used a retrospective dataset involving 257 GC patients (training cohort, n = 172; validation cohort, n = 85). First, several clinical indicators, including serum tumor markers, CT-TN stages and CT-detected extramural vein invasion (CT-EMVI), were extracted, as were quantitative spectral CT parameters from the delineated tumor regions. Next, a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters. A logistic regression (LR)-based nomogram model was subsequently constructed to predict LVI/PNI status, and its performance was evaluated using the area under the receiver operating characteristic curve (AUC).

RESULTS

In both the training and validation cohorts, CT T3-4 stage, CT-N positive status, and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant (P < 0.05). LR analysis of the training group showed preoperative CT-T stage, CT-EMVI, single-energy CT values of 70 keV of venous phase (VP-70 keV), and the ratio of standardized iodine concentration of equilibrium phase (EP-NIC) were independent influencing factors. The AUCs of VP-70 keV and EP-NIC were 0.888 and 0.824, respectively, which were slightly greater than those of CT-T and CT-EMVI (AUC = 0.793, 0.762). The nomogram combining CT-T stage, CT-EMVI, VP-70 keV and EP-NIC yielded AUCs of 0.918 (0.866-0.954) and 0.874 (0.784-0.936) in the training and validation cohorts, which are significantly higher than using each of single independent factors (P < 0.05).

CONCLUSION

The study found that using portal venous and EP spectral CT parameters allows effective preoperative detection of LVI/PNI in GC, with accuracy boosted by integrating clinical markers.

Study on the diagnostic value of MDCT extramural vascular invasion in preoperative N staging of gastric cancer patients

BACKGROUND

To explore the diagnostic value of multidetector computed tomography (MDCT) extramural vascular invasion (EMVI) in preoperative N Staging of gastric cancer patients.

METHODS

According to the MR-defined EMVI scoring standard of rectal cancer, we developed a 5-point scale scoring system to evaluate the status of CT-detected extramural vascular invasion(ctEMVI), 0-2 points were ctEMVI-negative status, and 3-4 points were positive status for ctEMVI. Patients were divided into ctEMVI positive group and ctEMVI negative group. The correlation between ctEMVI and clinical features was analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of ctEMVI for pathological metastatic lymph nodes and N staging, The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of pathological N staging using ctEMVI and short-axis diameter were generated and compared.

RESULTS

The occurrence rate of lymphovascular invasion (LVI) and proportion of tumors with a greatest diameter > 6 cm in the ctEMVI positive group was higher than that in the ctEMVI negative group (P < 0.05). Spearman correlation analysis showed a positive correlation between ctEMVI and LVI, N stage, and tumor size (P < 0.05). For ctEMVI scores ≥ 3,The AUC of ctEMVI for diagnosing lymph node metastasis, N stage ≥ N2, and N3 stage were 0.857, 0.802, and 0.758, respectively. The sensitivity, NPV and accuracy of ctEMVI for diagnosing N stage ≥ N2 were superior to those of short-axis diameter (P < 0.05), while sensitivity, specificity, PPV, NPV, and accuracy of ctEMVI for diagnosing N3 stage were superior to those of short-axis diameter (P < 0.05).

CONCLUSION

ctEMVI has important value in diagnosing metastatic lymph nodes and advanced N staging. As an important imaging marker, ctEMVI can be included in the preoperative imaging evaluation of patients, providing important assistance for clinical guidance and treatment.

Analysis of enhanced CT imaging signs and clinicopathological prognostic factors in hepatoid adenocarcinoma of stomach patients with radical surgery: a retrospective study

BACKGROUND

To investigate the association between CT signs and clinicopathological features and disease recurrence in patients with hepatoid adenocarcinoma of stomach (HAS).

METHODS

Forty nine HAS patients undergoing radical surgery were retrospectively collected. Association between CT and clinicopathological features and disease recurrence was analyzed. Multivariate logistic model was constructed and evaluated for predicting recurrence by using receiver operating characteristic (ROC) curve. Survival curves between model-defined risk groups was compared using Kaplan-Meier method.

RESULTS

24(49.0%) patients developed disease recurrence. Multivariate logistic analysis results showed elevated serum CEA level, peritumoral fatty space invasion and positive pathological vascular tumor thrombus were independent factors for disease recurrence. Odds ratios were 10.87 (95%CI, 1.14-103.66), 6.83 (95%CI, 1.08-43.08) and 42.67 (95%CI, 3.66-496.85), respectively. The constructed model showed an area under ROC of 0.912 (95%CI,0.825-0.999). The model-defined high-risk group showed poorer overall survival and recurrence-free survival than the low-risk group (both P < 0.001).

CONCLUSIONS

Preoperative CT appearance of peritumoral fatty space invasion, elevated serum CEA level, and pathological vascular tumor thrombus indicated poor prognosis of HAS patients.

A new radiomics approach combining the tumor and peri-tumor regions to predict lymph node metastasis and prognosis in gastric cancer

Objective

The development of non-invasive methods for evaluating lymph node metastasis (LNM) preoperatively in gastric cancer (GC) is necessary. In this study, we developed a new radiomics model combining features from the tumor and peri-tumor regions for predicting LNM and prognoses.

Methods

This was a retrospective observational study. In this study, two cohorts of patients with GC treated in Zhongshan Hospital Fudan University (Shanghai, China) were included. In total, 193 patients were assigned to the internal training/validation cohort; another 98 patients were assigned to the independent testing cohort. The radiomics features were extracted from venous phase computerized tomography (CT) images. The radiomics model was constructed and the output was defined as the radiomics score (RS). The performance of the RS and CT-defined N status (ctN) for predicting LNM was compared using the area under the curve (AUC). The 5-year overall survival and progression-free survival were compared between different subgroups using Kaplan-Meier curves.

Results

In both cohorts, the RS was significantly higher in the LNM-positive group than that in the LNM-negative group (all P < 0.001). The radiomics model combining features from the tumor and peri-tumor regions achieved the highest AUC in predicting LNM (AUC, 0.779 and 0.724, respectively), which performed better than the radiomics model based only on the tumor region and ctN (AUC, 0.717, 0.622 and 0.710, 0.603, respectively). The differences in 5-year overall survival and progression-free survival between high-risk and low-risk groups were significant (both P < 0.001).

Conclusions

The radiomics model combining features from the tumor and peri-tumor regions could effectively predict the LNM in GC. Risk stratification based on the RS was capable of distinguishing patients with poor prognoses.

Gastric adenocarcinoma: A review of the TNM classification system and ways of spreading

Gastric cancer is the fifth most common cancer in the world. The most common histologic subtype is adenocarcinoma. Gastric adenocarcinomas are staged using the American Joint Committee on Cancer's 8th TNM classification. The perigastric ligaments, mesentery, omentum, and potential spaces between the parietal and visceral peritoneal linings play are important structures for staging. The spread of disease is influenced by the location of the tumor within the stomach, as well as by the anatomy related to the ligaments and lymph vessels. CT is the imaging modality of choice for the preoperative clinical staging of gastric cancer, and it is essential for planning treatment. To be able to do an adequate imaging workup, radiologists need to know the different pathways through which gastric cancer can spread: lymphatic, subperitoneal, direct invasion, transperitoneal, hematogenous, and extramural venous invasion.

Correlation and prognostic value of CT-detected extramural venous invasion and pathological lymph-vascular invasion in colon cancer

PURPOSE

To explore the association between CT-detected extramural vascular invasion (ctEMVI) and lymph-vascular invasion (LVI) in colon cancer, and analyze the prognostic value of ctEMVI in different conditions of LVI.

METHODS

This single-center, retrospective study included 448 colon cancer patients from January 2015 to December 2017. Preoperative CT features and clinical and pathological data were collected. Associations between ctEMVI and LVI were tested. Univariate and multivariate logistic regression was performed. Multivariate Cox regression was performed adjusted with propensity score(PS). Kaplan-Meier method was used to compare survival differences between the ctEMVI and LVI groups. A 1:1 patient pairing was conducted using PS matching to assess the prognostic effect of ctEMVI in LVI subgroups.

RESULTS

Among the 448 patients, there were 261 men and 187 women, with an average age of 63 ± 12 years. The coincidence rate of ctEMVI and LVI was 73.9%. The k coefficient for identifying ctEMVI was 0.84. ctEMVI and LVI were both independent risk factors for overall survival (ctEMVI: HR 2.8, 95% CI 1.5-5.5; LVI: HR 2.2, 95% CI 1.2-4.1) and metastasis-free survival (ctEMVI: HR 3.3, 95% CI 1.7-6.4; LVI: HR 2.4, 95% CI 1.3-4.5) adjusted with PS. In the LVI(+) subgroup, the prognosis of ctEMVI(+) was significantly worse than that of ctEMVI(-); in the LVI(-) subgroup, the prognosis of different ctEMVI states was similar.

CONCLUSION

ctEMVI is an independent prognostic risk factor and has different prognostic value in different LVI states. It is recommended to perform the evaluation in routine work, especially for patients with positive LVI.

Value of multiphase contrast-enhanced CT with three-dimensional reconstruction in detecting depth of infiltration, lymph node metastasis, and extramural vascular invasion of gastric cancer

Background

Multiphase contrast-enhanced computed tomography (CECT) can reveal the location, morphology, size, and enhancement pattern of gastric cancer (GC), whereas the three-dimensional reconstruction (3DR) technique can better display the relationships of the lesions with surrounding structures, the feeding vessels, and lymph node metastasis. Here, we investigated the value of multi-phase CECT with 3DR in detecting depth of infiltration, lymph node metastasis, and extramural vascular invasion (EMVI) of GC.

Methods

The clinical and imaging data of 132 GC patients admitted to the Chongqing Hospital of Traditional Chinese Medicine and the Third Affiliated Hospital of Chongqing Medical University during the period from January 2012 to October 2019 were collected. All patients received plain and multiphase contrast-enhanced CT scans. The agreement between the results of preoperative CT evaluation and the surgical/pathological findings was compared.

Results

(I) CT findings of GC of 3 differentiation levels: on the multiphase CECT, the peak enhancement percentage was highest in the portal venous phase. The CT values significantly differed among the arterial, portal venous, and equilibrium phases (P<0.05); the differences in the arterial, portal venous, and equilibrium phases were statistically significant among the well-, moderately, and poorly differentiated groups (all P<0.05); finally, the difference in the equilibrium phase was statistically significant between the well- and moderately differentiated groups (P<0.05). (II) Preoperative CT and postoperative pathology had good consistency in T staging (Kappa =0.667). (III) The Kappa values between the preoperative CT-diagnosed lymph node metastasis and postoperative pathologically showing an increasing consistency with the increase of CT enhancement differences. (IV) Preoperative CT and postoperative pathology had good consistency in N staging (Kappa =0.779). (V) Preoperative CT in displaying arterial supply to the stomach. The rate of positive EMVI was 32.6% (43/132) on preoperative CT. The positive EMVI diagnosed by preoperative CT was correlated with tumor size, growth pattern, tissue differentiation degree, T stage, and N stage (all P<0.05).

Conclusions

Multiphase CECT combined with 3DR has high diagnostic performance in detecting the depth of infiltration, lymph node metastasis, and EMVI of GC.

Development and evaluation of a ceMDCT-based preoperative risk stratification model to predict disease-free survival after radical surgery in patients with gastric cancer

PURPOSE

To develop and evaluate a preoperative risk stratification model for predicting disease-free survival (DFS) based on contrast-enhanced multidetector computed tomography (ceMDCT) images in patients with gastric cancer (GC) undergoing radical surgery.

METHODS

We retrospectively enrolled patients with GC who underwent ceMDCT followed by radical surgery. A preoperative risk stratification model was constructed (including risk factor selection, risk status scoring, and risk level assignment) using Cox proportional hazard regression and log-rank analyses in the training cohort; the model was tested in the validation cohort. A nomogram was used to compare the preoperative risk stratification model with a postoperative DFS prediction model.

RESULTS

A total of 462 patients (training/validation: 271/191) were included. The ceMDCT features of T category (score of 0 or 2), N category (0, 1, 2, or 3), extramural vessel invasion (0 or 2), and tumor location (0 or 1) were selected to construct the preoperative risk stratification model, with 4 risk levels defined based on risk score. There were significant differences in DFS among the risk levels in both cohorts (p < 0.001). The predictive value of the preoperative model was similar to that of the postoperative model, with concordance indices of 0.791 (95% CI, 0.743-0.837) and 0.739 (95% CI, 0.666-0.812), respectively, in the training cohort and 0.762 (95% CI, 0.696-0.828) and 0.738 (95% CI, 0.684-0.792), respectively, in the validation cohort.

CONCLUSION

A preoperative risk stratification model based on ceMDCT images could be used to predict DFS and thus classify GC cases into various risk levels.

Value of quantitative dynamic contrast-enhanced and diffusion-weighted magnetic resonance imaging in predicting extramural venous invasion in locally advanced gastric cancer and prognostic significance

Background

Extramural venous invasion (EMVI) has been found to be related to poor prognosis in gastric cancer. Preoperative diagnosis of EMVI is challenging, as it can only be detected by surgical pathology. The present study aimed to investigate the value of quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) in predicting EMVI preoperatively, and to determine the relationship between prediction results and prognosis in patients with locally advanced gastric cancer (LAGC).

Methods

Between January, 2015, and June, 2017, 79 LAGC patients underwent MRI preoperatively were enrolled in this study. Pathological EMVI (pEMVI) was used as the gold standard for diagnosis. The differences in quantitative DCE-MRI and DWI parameters between groups with different pEMVI status were analyzed. Multivariate logistic regression was used to build the combined prediction model for pEMVI with statistically significant quantitative parameters. The performance of the model for predicting pEMVI was evaluated using receiver operating characteristic (ROC) analysis. Patients were grouped based on MRI-predicted EMVI (mrEMVI). Kaplan-Meier analysis was used to investigate the relationship between mrEMVI and 2-year recurrence-free survival (RFS).

Results

Of the 79 LAGC patients who underwent MRI, 29 were pEMVI positive and 50 were pEMVI negative. Among the patients' clinical and pathological characteristics, only postoperative staging showed a significant difference between the 2 groups (P=0.015). The pEMVI-positive group had higher volume transfer constant (K^trans) and rate constant (k_ep), and lower apparent diffusion coefficient (ADC) values than the negative group (0.189 vs. 0.082 min^-1, 0.687 vs. 0.475 min^-1, and 1.230×10^-3 vs. 1.463×10^-3 mm²/s, respectively; P<0.05). Quantitative parameters, K^trans and k_ep, and ADC values, were independently associated with pEMVI which odds ratio values were 3.66, 2.65, and 0.30 (P<0.05), respectively, using multivariate logistic regression. ROC analysis showed that the area under the curve, sensitivity, specificity, positive predictive value, and negative predictive value in predicting pEMVI using combined K^trans, k_ep, and ADC values were 0.879, 72.4%, 96%, 91.3%, and 85.7%, respectively. A total of 23 cases were considered to be mrEMVI positive, and 56 cases were considered to be mrEMVI negative, according to the predictive results. The median RFS of the mrEMVI-positive group was significant lower than the negative group (21.7 vs. 31.2 months), and the 2-year RFS rate in the mrEMVI-positive group was significantly lower than that of the negative group (43.6% vs. 72.5%, P=0.010).

Conclusions

The quantitative DCE-MRI parameters, K^trans and k_ep, and DWI parameter, ADC, are independent predictors of pEMVI in LAGC; mrEMVI was confirmed to be a poor prognostic predictor for RFS.

CT-detected extramural venous invasion is corelated with presence of lymph node metastasis and progression-free survival in gastric cancer

OBJECTIVE

This study aimed to investigate if CT-detected extramural venous invasion (ctEMVI) was associated with the presence of lymph node metastasis (LNM) and survival outcomes in patients with gastric cancer.

METHODS

We retrospectively reviewed 105 patients with pathologically proved gastric cancer who underwent pre-operative CT examinations and received radical gastrectomy with extended lymphadenectomy. Differences in CT characteristics between the LNM-positive and -negative groups were assessed by two observers. Binary logistic regression analysis was performed to determine the risk factors of lymph node metastasis in gastric cancer. Progression-free survival analysis was performed by Kaplan-Meier method.

RESULTS

Two observers reached good inter-reader agreements in ctEMVI and ctN status with κ values of 0.711 and 0.751, respectively. The frequency of ctEMVI-positive status was 58.1% (61/105) in patients with gastric cancer. The LNM-positive group showed higher possibility of ctEMVI-positive status (81.7% vs 26.7%, p＜0.001), larger tumor volume (mean volume, 40.77 vs 22.09 mL, p＜0.001), poor tumor margin (45.0% vs 26.7% , p = 0.054) and high enhancement on arterial phase (43.3% vs 26.7%, p = 0.023) and venous phase (60.0% vs 44.4%, p = 0.048), than LNM-negative group. In multivariate analysis, ctEMVI status and tumor volume were identified as independent risk factors for lymph node metastasis with odds ratio (OR) of 9.804 (95% CI, 3.076－31.246; p＜0.001) and 1.030 (95% CI, 1.001－1.060; p = 0.044). CT-detected EMVI presented better diagnostic efficiency for lymph node metastasis than CT-defined N status, with sensitivity (81.7% vs 70.0%), specificity (73.3% vs 71.1%), accuracy (78.1% vs 70.5), PPV (80.3% vs 76.4%), and NPV (75.0% vs 64.0%), respectively. Kaplan-Meier curves showed that patients with positive ctEMVI findings has lower PFS rate than patients with negative ctEMVI findings (Log-rank test, p = 0.007).

CONCLUSION

CT-detected EMVI was significantly associated with lymph node metastasis and progression free survival in patients with gastric cancer. Compared to CT-defined N status, ctEMVI provided superior diagnostic performance to predict pathologic Nstatus.

ADVANCES IN KNOWLEDGE

Our study proved that CT-detected EMVI is a promising imaging marker to predict lymph node metastasis and poor prognosis, which may contribute to the precise evaluation of gastric cancer before surgery.

CT-Detected Extramural Vessel Invasion and Regional Lymph Node Involvement in Stage T4a Gastric Cancer for Predicting Progression-Free Survival

OBJECTIVE. This study aimed to investigate the 3-year progression-free survival (PFS) of patients with stage T4a gastric cancer with extramural vessel invasion (EMVI) detected with contrast-enhanced (CE) MDCT. In addition, we investigated the possibility that CT of EMVI could improve clinical nodal (N) staging. MATERIALS AND METHODS. This retrospective study included 143 patients with T4a gastric cancer. Clinical staging was performed with CE-MDCT. All patients underwent radical gastrectomy with extended lymphadenectomy, adjuvant chemotherapy, and conventional follow-up visits. Potential prognostic factors, including CE-MDCT-detected N status, pathologic N status, EMVI detected at CT, tumor location or growth pattern, histologic type or tumor differentiation, and tumor size, were recorded. Survival estimates for PFS were obtained using the Kaplan-Meier product limit for the following patient subgroups: EMVI positive-N positive, EMVI positive-N negative, EMVI negative-N positive, and EMVI negative-N negative. Hazard ratios for 3-year PFS were generated using a Cox proportional hazard regression analysis. RESULTS. The frequency of EMVI detected at CT was 55.9% (80/143). The 3-year PFS rates were 25.0% for the EMVI positive-N positive group, 53.1% for the EMVI positive-N negative group, 75.6% for the EMVI negative-N positive group, and 64.7% for the EMVI negative-N negative group. The EMVI positive-N positive subgroup 3-year PFS rate was significantly lower than that of the other three groups (p < 0.05, log-rank test). Using Cox proportional hazards regression analysis, EMVI positive-N positive status was found to be an independent factor for reduced 3-year PFS, with a hazard ratio of 2.169 (95% CI, 1.300-3.618; p = 0.003). CONCLUSION. EMVI detected at CT, combined with N status detected with CE-MDCT, could be used as a valuable preoperative prognostic factor in patients with T4a gastric cancer.

Tumor thrombus in the venous drainage pathways of primary, recurrent and metastatic disease on routine oncologic imaging studies: beyond hepatocellular and renal cell carcinomas

Radiologists routinely evaluate for tumor thrombus in the portal and hepatic veins in patients with hepatocellular carcinoma and in the renal vein and inferior vena cava in patients with renal cell carcinoma. However, tumor thrombus occurs in association with numerous other tumor types, e.g. colorectal carcinoma and pancreatic neuroendocrine tumor. Furthermore tumor thrombi are not limited to the primary tumor but also seen with local recurrence and metastatic disease. While less recognized, these thrombi nevertheless affect patterns of recurrence and prognosis. Their detection is critical for accurate local staging and early detection of local recurrence and metastatic disease. The purpose of this pictorial review is to draw the attention of radiologists to the less familiar manifestations of tumor thrombus, review the imaging findings and illustrate the clinical significance of these thrombi.

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 ( P = 0.019). 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.

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

PURPOSE

To 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 stage III gastric cancer.

METHODS

Between January 2009 and December 2013, 117 patients with pathological-proved stage III gastric 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 12 months 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.

RESULTS

The prevalence of EMVI detected with ceMDCT was 43.6% (51/117) in patients with stage III gastric cancer. The EMVI-positive patients had significantly lower 1-year PFS rates (45.1%), than the EMVI-negative patients (75.8%), (Log-rank test, P = 0.0008). 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, P = 0.021) and 1.982 (95% CI 1.040-3.780, P = 0.039), respectively.

CONCLUSION

EMVI status, detected with ceMDCT, could be used to counsel patients regarding ongoing risks of metastatic disease, implications for surveillance, and systemic chemotherapy.