Incorporation of perineural invasion of gastric carcinoma into the 7th edition tumor–node–metastasis staging system

Development and External Validation of a CT-Based Radiomics Nomogram to Predict Perineural Invasion and Survival in Gastric Cancer: A Multi-institutional Study

RATIONALE AND OBJECTIVES

To develop and validate a radiomics nomogram utilizing CT data for predicting perineural invasion (PNI) and survival in gastric cancer (GC) patients.

MATERIALS AND METHODS

A retrospective analysis of 408 GC patients from two institutions: 288 patients from Institution I were divided 7:3 into a training set (n = 203) and a testing set (n = 85); 120 patients from Institution II served as an external validation set. Radiomics features were extracted and screened from CT images. Independent radiomics, clinical, and combined models were constructed to predict PNI. Model discrimination, calibration, clinical utility, and prognostic significance were evaluated using area under the curve (AUC), calibration curves, decision curves analysis, and Kaplan-Meier curves, respectively.

RESULTS

15 radiomics features and three clinical factors were included in the final analysis. The AUCs of the radiomics model in the training, testing, and external validation sets were 0.843 (95% CI: 0.788-0.897), 0.831 (95% CI: 0.741-0.920), and 0.802 (95% CI: 0.722-0.882), respectively. A nomogram was developed by integrating significant clinical factors with radiomics features. The AUCs of the nomogram in the training, testing, and external validation sets were 0.872 (95% CI: 0.823-0.921), 0.862 (95% CI: 0.780-0.944), and 0.837 (95% CI: 0.767-0.908), respectively. Survival analysis revealed that the nomogram could effectively stratify patients for recurrence-free survival (Hazard Ratio: 4.329; 95% CI: 3.159-5.934; P < 0.001).

CONCLUSION

The radiomics-derived nomogram presented a promising tool for predicting PNI in GC and held significant prognostic implications.

IMPORTANT FINDINGS

The nomogram functioned as a non-invasive biomarker for determining the PNI status. The predictive performance of the nomogram surpassed that of the clinical model (P < 0.05). Furthermore, patients in the high-risk group stratified by the nomogram had a significantly shorter RFS (P < 0.05).

Preoperative Risk Stratification for Gastric Cancer: The Establishment of Dual-Energy CT-Based Radiomics Using Prospective Datasets at Two Centers

RATIONALE AND OBJECTIVES

To evaluate the performance of dual-energy CT (DECT)-based radiomics models for identifying high-risk histopathologic phenotypes-serosal invasion (pT4a), lymph node metastasis (LNM), lymphovascular invasion (LVI) and perineural invasion (PNI) in gastric cancer.

MATERIAL AND METHODS

This prospective bi-center study recruited histologically confirmed gastric adenocarcinoma patients who underwent triple-phase enhanced DECT before gastrectomy between January 2021 and July 2023. Radiomics features were extracted from polychromatic/monochromatic (40 keV, 100 keV)/iodine images at arterial/venous/delay phase, respectively. Predictive features were selected in the training dataset using logistic regression classifier, and trained models were applied to the external validation dataset. Performances of clinical models, conventional contrast enhanced CT (CECT) models and DECT models were evaluated using areas under the receiver operating characteristic curve (AUCs).

RESULTS

In total, 503 patients were recruited: 396 at training dataset (60.1 ± 10.8 years, 110 females, 286 males) and 107 at validation dataset (61.4 ± 9.5 years, 29 females, 78 males). DECT models dichotomizing pT4a, LNM, LVI, and PNI achieved AUCs of 0.891, 0.817, 0.834, and 0.889, respectively, in the validation dataset, similar with the CECT models. In the training dataset, compared to the CECT model, the DECT model provided increased performance for identifying pT4a, LNM, LVI (all P＜0.05), and similar performance for stratifying PNI (P = 0.104). The DECT models was associated with patient disease-free survival (all P＜0.05).

CONCLUSION

DECT radiomics can stratify patients preoperatively according to high-risk histopathologic phenotypes for gastric cancer and are associated with patient disease-free survival in the training dataset.

Construction of a preoperative nomogram model for predicting perineural invasion in advanced gastric cancer

Objective

This study aimed to develop and validate a clinical and imaging-based nomogram for preoperatively predicting perineural invasion (PNI) in advanced gastric cancer.

Methods

A retrospective cohort of 351 patients with advanced gastric cancer who underwent surgical resection was included. Multivariable logistic regression analysis was conducted to identify independent risk factors for PNI and to construct the nomogram. The performance of the nomogram was assessed using calibration curves, the concordance index (C-index), the area under the curve (AUC), and decision curve analysis (DCA). The disparity in disease-free survival (DFS) between the nomogram-predicted PNI-positive group and the nomogram-predicted PNI-negative group was evaluated using the Log-Rank test and Kaplan-Meier analysis.

Results

Extramural vascular invasion (EMVI), Borrmann classification, tumor thickness, and the systemic inflammation response index (SIRI) emerged as independent risk factors for PNI. The nomogram model demonstrated a commendable AUC value of 0.838. Calibration curves exhibited excellent concordance, with a C-index of 0.814. DCA indicated that the model provided good clinical net benefit. The DFS of the nomogram-predicted PNI-positive group was significantly lower than that of the nomogram-predicted PNI-negative group (p < 0.001).

Conclusion

This study successfully developed a preoperative nomogram model that not only effectively predicted PNI in gastric cancer but also facilitated postoperative risk stratification.

The value of intravoxel incoherent motion diffusion-weighted imaging in predicting perineural invasion for resectable gastric cancer: a prospective study

AIM

To investigate the potential of intravoxel incoherent motion (IVIM) diffusion-weighted imaging to predict perineural invasion (PNI) preoperatively in resectable gastric cancer (GC).

MATERIALS AND METHODS

This study prospectively recruited 85 surgically resected GC patients (58 men, 27 women) aged 60.87 ± 10.17 (39-81) years, who underwent IVIM sequence within 1 week before surgery. According to histopathological PNI diagnoses, patients were divided into PNI positive and negative groups. Conventional apparent diffusion coefficient (ADC) and the IVIM parameters, including true diffusion coefficient (D), pseudodiffusion coefficient (D∗), and pseudodiffusion fraction (f), were compared between the two groups. Morphological MRI features were also analysed. Multivariate logistic regression was used to screen independent predictors of PNI. Receiver-operating characteristic curve analyses were preformed to evaluate the efficacy. Spearman's correlation test was performed to analyse the relationship between MRI parameters and PNI.

RESULTS

Tumour thickness and f in PNI-positive group were higher, whereas the ADC, D were lower than those in PNI-negative group (p<0.05). These four parameters correlated with PNI (p<0.05). The D, f, and tumour thickness were independent predictors of PNI. The area under the curve of ADC, D, f, thickness, and the combined parameter (D + f + thickness) were 0.648, 0.745, 0.698, 0.725, and 0.869, respectively. The combined parameter demonstrated higher efficacy than any other parameters (p<0.05).

CONCLUSION

The ADC, D, and f can effectively distinguish PNI status in GC. The D, f, and thickness were independent predictors of PNI.

Inclusion of Perineural Invasion with AJCC-TNM Staging: Outcomes from a South Asian Cohort of Curatively Treated Gastric Cancer Patients

BACKGROUND

The incidence of perineural invasion (PNI) in patients with gastric cancer (GC) is high, and patients with PNI positive disease have a poor prognosis compared to PNI-negative disease. The present study aims to study the incidence and evaluate the impact of PNI on the survival outcome of a cohort of South Asian GC patients.

MATERIAL AND METHODS

All consecutive patients undergoing curative gastrectomy were included in the study. The incidence of PNI and correlation with different clinico-pathological features and overall survival was performed.

RESULTS

A total of 59.54% had PNI-positive disease and the median OS of PNI + ve patients was 29.3 months, while it was not reached in PNI-ve patients. The PNI positivity was a significant prognostic factor for overall survival both on univariate and multivariate analysis. On TNM-PNI staging, those with TNM stage I/II patients with PNI + ve disease had similar OS to all stage III patients (p = 0.835) and were worse than that of PNI-ve patients (p < 0.05).

CONCLUSION

The incidence of PNI in gastric cancer is high. The inclusion of PNI with AJCC-TNM staging may better stratify prognostic staging in curatively treated gastric cancer patients.

Spectral CT-based nomogram for preoperative prediction of perineural invasion in locally advanced gastric cancer: a prospective study

OBJECTIVES

This work focused on developing and validating the spectral CT-based nomogram to preoperatively predict perineural invasion (PNI) for locally advanced gastric cancer (LAGC).

METHODS

This work prospectively included 196 surgically resected LAGC patients (139 males, 57 females, 59.55 ± 11.97 years) undergoing triple enhanced spectral CT scans. Patients were labeled as perineural invasion (PNI) positive and negative according to pathologic reports, then further split into primary (n = 130) and validation cohort (n = 66). We extracted clinicopathological information, follow-up data, iodine concentration (IC), and normalized IC values against to aorta (nICs) at arterial/venous/delayed phases (AP/VP/DP). Clinicopathological features and IC values between PNI positive and negative groups were compared. Multivariable logistic regression was performed to screen independent risk factors of PNI. Then, a nomogram was established, and its capability was determined by ROC curves. Its clinical use was evaluated by decision curve analysis. The correlations of PNI and the nomogram with patients' survival were explored by log-rank survival analysis.

RESULTS

Borrmann classification, tumor thickness, and nICDP were independent predictors of PNI and used to build the nomogram. The nomogram yielded higher AUCs of 0.853 (0.744-0.928) and 0.782 (0.701-0.850) in primary and validation cohorts than any other parameters (p < 0.05). Both PNI and the nomogram were related to post-surgical treatment planning. Only PNI was associated with disease-free survival in the primary cohort (p < 0.05).

CONCLUSION

This work prospectively established a spectral CT-based nomogram, which can effectively predict PNI preoperatively and potentially guide post-surgical treatment strategy in LAGC.

KEY POINTS

• The present prospective study established a spectral CT-based nomogram for preoperative prediction of perineural invasion in LAGC. • The proposed nomogram, including morphological features and the quantitative iodine concentration values from spectral CT, had the potential to predict PNI for LAGC before surgery, along with guide post-surgical treatment planning. • Normalized iodine concentration at the delayed phase was the most valuable quantitative parameter, suggesting the importance of delayed enhancement in gastric CT.

Nerve invasion as an independent predictor of poor prognosis in gastric cancer after curative resection

The study aims to reveal the clinical significance of perineural invasion (PNI) for gastric cancer prognosis and determine the risk factors of PNI in gastric cancer. This study retrospectively analyzed 350 patients who were diagnosed with GC and underwent curative surgical resection. Variables used to analyze survival included gender, age, degree of differentiation, T classification, lymph node metastasis, lymphovascular invasion, nerve invasion, mucinous adenocarcinoma component, and signet ring cell carcinoma component. The tumors of all patients were surgically resected. All resected specimens were stained with hematoxylin-eosin and immunohistochemical. The data for the patient's lymphovascular invasion and PNI came from the collected pathological reports. The results of the survival analysis showed that T staging (P < .001), lymph node metastasis (P < .001), lymphovascular invasion (P = .013), PNI (P = .001), and signet ring cell carcinoma components (P = .046) affect the survival time and have a statistically significant difference. Multivariate analysis indicated that the positivity of PNI was an independent prognostic factor (P = .014). T staging (P = .006) and lymph node metastasis (P = .013) were independent prognostic parameters too. Using the Spearman correlation analysis, the following clinicopathological indicators were associated with PNI positivity, such as tumor differentiation, T staging, lymph node metastasis, vascular invasion, and signet ring cell carcinoma components (P < .05). PNI is an independent marker of poor prognosis in patients with gastric cancer.

Prognostic Significance of Perineural Invasion in Patients with Stage II/III Gastric Cancer Undergoing Radical Surgery

The prognostic significance of perineural invasion in patients with gastric cancer (GC) is controversial. This study aimed to determine the prognostic value of perineural invasion in patients with stage II/III GC undergoing radical surgery. A total of 1913 patients with stage II/III GC who underwent curative resection between 1994 and 2015 were recruited. Clinicopathological factors, tumor recurrence patterns, disease-free survival, and cancer-specific survival were compared in terms of perineural invasion. The prognostic factors of disease-free survival and cancer-specific survival were determined using univariate and multivariate analyses. Perineural invasion was found in 57.1% of the patients. Age of <65 years, female sex, large tumor size, upper tumor location, total gastrectomy, advanced tumor invasion depth and nodal involvement, greater metastatic to examined lymph node ratio, undifferentiated tumor, and presence of lymphatic or vascular invasion were significantly associated with perineural invasion. The patients with perineural invasion had higher locoregional/peritoneal recurrence rates than those without. Perineural invasion was independently associated with disease-free survival and cancer-specific survival. In conclusion, perineural invasion positivity is associated with aggressive tumor behaviors and higher locoregional/peritoneal recurrence rates in patients with stage II/III GC undergoing curative surgery. It is an independent unfavorable prognostic factor of disease recurrence and cancer-specific survival.

Is Adjuvant Chemotherapy Beneficial to All Patients With pT3N0M0 Stage Gastric Cancer?

Background

The efficacy and benefits of adjuvant chemotherapy (AC) for patients with gastric cancer pT3N0M0 remain controversial.

Methods

We prospectively collected and retrospectively analyzed 235 patients with pT3N0M0 gastric cancer who underwent radical resection between February 2010 and January 2016. Patients were divided into two groups: the surgery-alone (SA) group (n = 82) and the AC group (n = 153). We analyzed the effects of AC on the overall survival (OS) and recurrence-free survival (RFS), and the relationship between the number of chemotherapy cycles (CC) and recurrence rate (RR).

Results

The 5-year OS and RFS of the participants were 80.9% and 87.7%, respectively, and those in the AC group were significantly higher than those in the SA group (86.9% vs. 69.5%, p = 0.003). The RFS of the AC and SA groups were 88.9% and 85.4%, respectively; the difference was not statistically significant (p = 0.35). The independent risk factors affecting the OS were perineural invasion-positive (PNI+) (HR = 2.64, 95%CI: 1.45-4.82, p = 0.003) and age ≥ 65 years (HR = 2.58, 95%CI: 1.39-4.8, p = 0.003). The independent risk factor affecting the RFS was also PNI+ (HR3.11; 95%CI: 1.48-6.54, p = 0.003). Stratified analysis revealed that postoperative AC can significantly improve the OS of PNI+ patients (AC group versus SA group: 84.1% vs. 45.5%, p = 0.001) and RFS (86.4% vs. 63.6%, p = 0.017). However, perineural invasion negative (PNI-) patients did not show the same results (p = 0.13 and p = 0.48, respectively). According to the number of CC, divided into CC < 3 groups and CC ≥ 3 groups, the cumulative RR in the CC ≥ 3 group of patients with PNI+ was significantly lower than that of the CC < 3 group (7.4% vs. 28.2%, p = 0.037).

Conclusion

For pT3N0M0 gastric cancer patients with PNI+, at least three cycles of postoperative AC can significantly reduce the overall RR. This finding should be verified by using large external sample data.

Disease-Specific Survival of AJCC 8th Stage II Gastric Cancer Patients After D2 Gastrectomy

The association between the risk factors and long-term prognosis in patients with stage II gastric cancer after radical gastrectomy has been fully revealed. The purpose of this study was to investigate the independent risk factors for treatment failure in stage II gastric cancer. Demographic, clinical, and pathological information of 247 stage II gastric cancer patients who underwent radical D2 gastrectomy in our department between January 2011 and December 2014 were collected and retrospectively analyzed. The relationship between and long-term clinical outcomes of stage II gastric cancer was analyzed using t-tests, chi-square tests, receiver operating characteristic (ROC) analysis, time-dependent ROC analysis, K–M curves, and a Cox regression model. The median follow-up of 247 stage II gastric cancer patients was 5.49 years (range: 0.12–8.62 years). The Kaplan–Meier estimated 3-year and 5-year DSS rates of the study group were 92.7% (95% CI 89.4–95.9) and 88.7% (95% CI 84.7–92.7), respectively. Higher age (>70 vs. ≤70, log-rank p = 0.0406), nerve invasion (positive vs. negative, log-rank p = 0.0133), and non-distal gastrectomy (distal partial gastrectomy vs. other surgical methods, log-rank p = 0.00235) had worse prognoses compared to controls. Univariate and multivariate analyses of disease-specific survival showed that these three factors were independent prognostic factors for patients with stage II disease. The area under time-dependent ROC curve (AUC) is 0.748 of 5-year survival and c-index is 0.696 based on the three-marker model drawn for stage II patients. Subgroup analyses showed an interaction between tumor location and nerve invasion. The age, perineural invasion, and surgical approach are independent prognostic factors for disease-specific survival after radical gastrectomy. Tumor location may be an important confounding factor for outcomes by affecting surgical methods and the hazards of nerve invasion.

Impact of the extent of negative lymph nodes in gastric adenocarcinoma undergoing primary surgical resection: An institutional report

BACKGROUND

Sub-total/total gastrectomy with lymph node dissection (LND) remains an effective therapeutic strategy for resectable gastric adenocarcinomas (GACs). Despite the prognostic significance of positive lymph nodes (PLNs) defined in N-status, few have appraised the impacts of negative lymph nodes (NLNs) and the percentage of NLN (=number of NLNs/number of total lymph nodes [TLNs], %), as well as the extent of TLNs to be dissected in GACs.

METHODS

We retrospectively analyzed 62 GAC patients (mean age of 67.1 years; 41 men) undergoing primary sub-total/total gastrectomy from a single institute. Candidate variables, including the number of NLNs (≤9 and >9) and the percentage of NLN (≤37.5, 37.5-80.6 and >80.6, %), were evaluated to determine their prognostic impacts and hazard ratios (HRs).

RESULTS

Under the multivariate Cox proportional-hazards regression model, tumor length exceeding 4 cm (p = 0.017; HR = 2.828), perineural invasion (p = 0.037; HR = 3.182), and lower percentage of NLN (p = 0.016 and p = 0.060; HRs = 1.000, 0.327, and 0.333 for subgroups ≤37.5, 37.5-80.6, and >80.6, respectively) were three independent predictors with elevated HRs for poor prognosis. GAC patients with the percentage of NLN > 80.6 were highly related to those with NLNs > 9 (p < 0.001), and GAC patients with NLNs > 9 were highly related to those with TLNs > 15 (p < 0.001). For all 62 GAC or 42 N(+) GAC patients, those who underwent LND with TLNs>15 tended to have more PLNs (p = 0.018, p = 0.003) and more NLNs (p < 0.001, p = 0.029) than did those with TLNs ≤ 15. Among the 42 GAC patients with TLNs > 15, a lower percentage of NLN (p = 0.026 and p = 0.015; HRs = 1.000, 0.272, and 0.180 for subgroups ≤37.5, 37.5-80.6, and >80.6, respectively) remained an independent predictor of poor prognosis.

CONCLUSION

The percentage of NLN could predict the prognosis of GAC patients properly. However, an accurate percentage of NLN needs a minimal requirement of TLNs > 15 to detect an adequate number of PLNs and sufficient number of NLNs.

The Impact of Nerve Involvement on the Prognosis of Gastric Cancer Patients with Curative Gastrectomy: An International Multicenter Analysis

Background

Several studies have been conducted to investigate the association between the presence of perineural invasion (PNI) and overall survival (OS) of gastric cancer (GC) patients who underwent curative resection, but no consensus has been reached. This study is aimed at determining the prognostic significance of PNI in gastric cancer. Study Design. The data of 2969 patients with gastric cancer and who had undergone curative gastrectomy from 2006 to 2010 in two high-volume hospitals of China and Korea were retrospectively analyzed. PNI positivity was identified when carcinoma cells were found to infiltrate into the perineurium or neural fascicles. The relationships between PNI and other clinicopathological factors were evaluated, and survival analyses were performed.

Results

The presence of PNI was detected in 1055 of the 2969 patients (35.5%). Nationality, age, tumor location, size of tumor, differentiation of the tumor, pT stage, pN stage, lymphatic invasion, and vascular invasion had been associated with PNI positivity. The mean survival time of patients with and without PNI was 62.5 months and 87.3 months, respectively (P < 0.001). However, the presence of PNI was not an independent prognostic factor for gastric cancer, except for patients in stage III (P = 0.037, hazard ratio: 1.21, 95% confidence interval: 1.01-1.44).

Conclusion

PNI occurs frequently in patients with gastric cancer, and the incidence of PNI increases with the staging of the tumor. The presence of PNI can provide additional information in predicting the survival outcome for those with stage III tumors.

Nomogram based on clinical characteristics for preoperative prediction of perineural invasion in gastric cancer

Purpose

Gastric cancer (GC) has a poor prognosis and high rate of recurrence. Perineural invasion (PNI) is a prognostic factor in GC that is associated with a high risk of systemic recurrence. Preoperative identification of PNI may facilitate patient stratification and optimal preoperative treatment. We therefore developed and validated a nomogram for the preoperative prediction of PNI.

Methods

We retrospectively collected clinical data from 261 GC patients, who were randomly assigned to training (n = 185) and validation (n = 76) sets. The least absolute shrinkage and selection operator regression model was used to identify potentially relevant clinical parameters, and multivariable logistic regression analysis was used to develop the nomogram.

Results

The nomogram consisted of body mass index, immunoglobulin A level, and computed tomography-based T- and N-stages. Good calibration was observed for both the training and validation sets, with areas under the curve of 0.77 and 0.79, respectively. Decision curve analysis revealed that the nomogram was clinically relevant.

Conclusion

We developed and validated a nomogram for the preoperative prediction of PNI in patients with GC. Our nomogram may facilitate the identification of high-risk patients and optimization of preoperative decision-making.

Perineural invasion as a predictive factor for survival outcome in gastric cancer patients: a systematic review and meta-analysis

AIMS

The prognostic significance of perineural invasion (PNI) for gastric cancer (GC) patients was under debate. This study aimed to review relevant studies and evaluate the impact of PNI on the survival outcome of GC patients.

METHODS

Systematic literature search was performed using PubMed and Embase databases. The relevant data were extracted, and the association between PNI and clinicopathological characteristics or survival outcome in GC patients were evaluated using a fixed-effect model or random-effect model.

RESULTS

A total 13 studies involving 7004 GC patients were included in this meta-analysis. The positive rate of PNI was 35.9% (2512/7004) in GC patients, ranging from 6.9% to 75.6%. There were significant relationships between PNI and a series of unfavourable clinicopathological factors including undifferentiated histology type (OR: 1.78, 95% CI 1.37 to 2.33, p<0.001; I²=75.3%), diffuse type (OR: 1.96, 95% CI 1.07 to 3.60, p=0.029; I²=79.5%), lymphatic invasion (OR: 7.00, 95% CI 3.76 to 13.03, p<0.001; I²=83.6%), vascular invasion (OR: 5.79, 95% CI 1.59 to 21.13, p=0.008; I²=95.8%), deeper tumour invasion (OR: 4.79, 95% CI 3.65 to 6.28, p<0.001; I²=65.0%) and lymph node metastasis (OR: 3.60, 95% CI 2.37 to 5.47, p<0.001; I²=89.6%). In addition, PNI was significantly associated with worse survival outcome in GC patients (HR: 1.69, 95% CI 1.38 to 2.06, p<0.001; I²=71.0%).

CONCLUSION

PNI was frequently detected in surgically resected specimens of GC patients, and it was a predictive factor for survival outcomes in these patients.

Tumor necrosis factor-related apoptosis-inducing ligand inhibits the growth and aggressiveness of colon carcinoma via the exogenous apoptosis signaling pathway

Colon cancer is one of the most common types of gastrointestinal tumor. Previous studies have demonstrated that tumor necrosis factor-(TNF)-related apoptosis-inducing ligand (TRAIL) reduces the aggressiveness of colon cancer tumors and promotes the apoptosis of colon carcinoma cells. In the present study, the inhibitory effects of TRAIL were investigated and the potential mechanism of TRAIL-mediated apoptosis was explored in colon cancer cells. Reverse transcription-quantitative polymerase chain reaction, western blotting, immunofluorescence, immunohistochemistry, TUNEL and flow cytometry assays were used to analyze the effects of TRAIL on the growth, migration, invasion and apoptosis of colon tumor cells. In vivo experiments were performed in mice to analyze the therapeutic effects of TRAIL. The results demonstrated that TRAIL significantly suppressed the growth of colorectal tumor cells in a dose-dependent manner (0.5–2.5 mg/ml) and also promoted colon tumor cell death. The migration and invasion of colon tumor cells were inhibited by the downregulation of fibronectin, Vimentin and E-cadherin. The apoptotic rate revealed that TRAIL (2.0 mg/ml) significantly promoted the apoptosis of colon tumor cells by regulating apoptosis-related gene expression. TRAIL administration promoted the apoptosis of colon tumor cells via the exogenous apoptosis signaling pathway due to the upregulation of caspase-3, caspase-8 and nuclear factor-κB protein expression. In vivo assays revealed that TRAIL administration significantly inhibited tumor growth and promoted apoptotic body and lymphocyte infiltration, which led to increased survival in tumor-bearing mice compared with the control group. Immunohistochemistry revealed that P53 and B-cell lymphoma-2 were downregulated in TRAIL-treated tumors. In conclusion, TRAIL treatment significantly inhibited the growth and aggressiveness of colon tumors by inducing apoptosis via the exogenous apoptosis pathway, which suggests that TRAIL may be a potential anticancer agent for colon carcinoma therapy.

Computed Tomography-Based Diagnosis of Gastric Vein Invasion in Patients with Gastric Cancer

Objective

The objective of this study was to demonstrate computed tomography (CT)-based diagnosis of venous invasion in patients with gastric cancer and its prognostic value.

Materials and Methods

Medical records and CT examinations of 530 patients with gastric cancer diagnosed after biopsy from February 2003 to December 2015 were included in this retrospective study. An imaging-based diagnosis of venous invasion was established when one of the following criteria were satisfied: 1) tumoral enhancement in the lumen of the vein, 2) tumor protruding through the course of a vein, and 3) distention of the vein due to extension of the gastric tumor. CT-based diagnosis of gastric vein invasion was established in 11/530 patients.

Results

Histopathological examination revealed poorly differentiated gastric adenocarcinoma (n=10) and neuroendocrine carcinoma (n=1). The median survival of the patients after the initial CT was 153.5 (range: 6-1275) days. Tumor invasion was observed at the aberrant left gastric vein (n=2), right gastroepiploic and superior mesenteric vein (n=2), gastric vein (n=4), and short gastric vein (n=3). Two of the three patients with short gastric vein invasion died 6 and 7 days after the initial CT, respectively.

Conclusion

All draining veins of the stomach can be invaded by gastric cancer; CT can enable diagnosis that may be important for prognosis and surgical planning. The presence of short gastric vein invasion detected by CT may be associated with poor prognosis.

Neural Invasion is a Significant Contributor to Peritoneal Recurrence in Signet Ring Cell Gastric Carcinoma

BACKGROUND

Gastric signet ring cell carcinoma (SRC) has shown a favorable outcome in early stages but has a worse prognosis than non-SRC in advanced stages. However, the cause for this stage-dependent prognostic impact has not been determined. This study aimed to compare clinicopathologic features and recurrence patterns between gastric SRC and non-SRC in a cohort of Eastern patients.

METHODS

This study reviewed the prospectively collected data of 764 patients undergoing curative resection for gastric cancer from 2005 to 2008. The demographics, clinicopathologic characteristics, disease-specific survival (DSS) rate, and recurrence-free survival (RFS) rate of the patients were analyzed.

RESULTS

The SRC patients (n = 176) had a worse prognosis than the non-SRC patients (n = 588), especially in stages T3 and T4. Peritoneal recurrence and the incidence of neural invasion (NI) were significantly increased in the SRC patients, albeit only in stages T3 and T4. In the T3 and T4 patients with NI, peritoneal recurrence occurred more frequently in SRC than in non-SRC (28.7% vs. 13.7%; p = 0.001), but not in the T3 and T4 patients without NI. Only in the patients with NI, SRC led to a significantly shorter DSS (67.6 vs. 90.7 months; p = 0.008) and RFS (67.1 vs. 80.3 months; p = 0.036) than non-SRC.

CONCLUSIONS

This report is the first to present the relationship between NI and peritoneal recurrence as the cause of stage-dependent prognoses for SRC. A better understanding of NI may lend insight into cancer spread and recurrence, especially in gastric SRC.

Resistant starch prevents tumorigenesis of dimethylhydrazine-induced colon tumors via regulation of an ER stress-mediated mitochondrial apoptosis pathway

Resistant starch is as common soluble fiber that escapes digestion in the small intestine and can regulate intestinal function, metabolism of blood glucose and lipids, and may prevent tumorigenesis of gastrointestinal cancer. Epidemiology and other evidence have suggested that resistant starch may prevent colon cancer development. The aim of the current study was to explore the ameliorative effects and potential mechanisms of resistant starch in the tumorigenesis of colon tumors induced by dimethylhydrazine in C57BL/6 mice. Western blot analysis, ELISA, microscopy, immunofluorescence and immunohistochemistry were used to analyze the efficacy of resistant starch on the metabolic balance in the colon and tumorigenesis of colon tumors. The results demonstrated that a diet containing resistant starch decreased the animal body weight and reduced free ammonia, pH and short chain fatty acids in feces compared with mice that received a standard diet. Resistant starch reduced the incidence of colon tumors and suppressed the expression of carcinogenesis-associated proteins, including heat shock protein 25, protein kinase C-d and gastrointestinal glutathione peroxidase in colon epithelial cells compared with standard starch and control groups. Colon tumor cells proliferation and dedifferentiation were significantly decreased by a resistant starch diet. The results also demonstrated that resistant starch increased the apoptosis of colon tumor cells through regulation of apoptosis-associated gene expression levels in colon tumor cells. Oxidative stress and endoplasmic reticulum stress were upregulated, and elevation eukaryotic translation initiation factor 2α (eIF2α), activating transcription factor-4 and secretase-β expression levels were increased in the resistant starch diet group. Additionally, the activity of eIF2α and PERK were increased in colon tumor cells from mice that had received resistant starch. Increasing DNA damage-inducible transcript 3 protein (CHOP), binding immunoglobulin protein (BIP) and caspase-12 expression levels upregulated by resistant starch diet may contribute to the resistant starch-induced apoptosis of colon tumor cells induced by 1,2-dimethylhydrazine. In vitro assays demonstrated that knockdown of eIF2α inhibited apoptosis of colon tumor cells isolated from mice fed with resistant starch, which also downregulated CHOP, BIP and caspase-3 expression levels compared with controls. Furthermore, long-term survival of experimental mice was prolonged by the resistant starch diet compared with the standard diet group. In conclusion, the results indicate that resistant starch in the diet may prevent carcinogenesis of colon epithelial cells, mediated by enhancing apoptosis through an endoplasmic reticulum stress-mediated mitochondrial apoptosis pathway.

Extramural Perineural Invasion in pT3 and pT4 Gastric Carcinomas

Background

Perineural invasion (PNI) is widely studied in malignant tumors, and its prognostic significance is well demonstrated. Most studies have focused on evaluating the mural PNI (mPNI); however, extramural PNI (ePNI) may influence the prognosis in gastric cancer. We evaluated the prognostic value of ePNI compared with mPNI in gastric cancer in this observational comparative cross-sectional study.

Methods

Seventy-three pT3 and pT4 gastric carcinomas with PNI were evaluated. Forty-eight (65.7%) were in the mPNI group and the remaining in the ePNI group.

Results

Clinicopathologic characteristics between the two groups were similar, except for the outcomes. The 5-year disease-specific survival (DSS) rate was 64% for the mPNI group and 50% for the ePNI group (p=.039), a difference that did not remain significant in multivariate analysis. The only independent adverse prognostic factor in multivariate analysis was the presence of lymph node metastasis (hazard ratio, 1.757; 95% confidence interval, 1.082 to 2.854; p=.023).

Conclusions

We demonstrated the prognostic effect of ePNI for DSS in surgically resected pT3–pT4 gastric cancer patients. ePNI could be considered in the staging and prognostic systems of gastric cancer to stratify patients with a high risk of recurrence.

Prognostic Value of Perineural Invasion in Resected Gastric Cancer Patients According to Lauren Histotype

The purpose of this study is to investigate perineural invasion (PNI) as a prognostic factor in gastric cancer patients. 455 patients submitted to extended (D2 or more) lymphadenectomy (median number of 39 retrieved lymph nodes, range: 15-140) between 1995 and 2012 were retrospectively studied. Patients were categorized in two groups according to the PNI status, and PNI positivity was assessed in presence of cancer cells in the perinerium or the neural fascicles using hematoxylin and eosin staining. Median follow-up for surviving patients was 80.3 months. Survival analysis was performed by univariate and multivariate analysis, using a Cox proportional hazards model. 162 patients (33.9%) had positive PNI; this was strongly associated with advanced stages of disease, residual tumor, lymphovascular invasion, Lauren diffuse-mixed histotype and tumor size. Five-year cancer-related survival was 65,7% and 20,6% in PNI negative vs. positive groups, respectively (p < 0.001). The prognostic impact of PNI at univariate analysis was particularly evident in patients submitted to R0 surgery, early as well as advanced stage, advanced nodal stage and T status. At multivariate analysis, PNI did not result statistically significant in the overall series, but emerged as an independent prognostic factor in the group of patients with Lauren intestinal histotype (p = 0.005, hazard ratio: 1.99, 95% confidence interval 1.24-3.19). PNI is related to advanced stage and poor long-term survival in gastric cancer, and may serve as an adjunctive prognostic factor in the intestinal histotype.

MicroRNA target for MACC1 and CYR61 to inhibit tumor growth in mice with colorectal cancer

Cysteine-rich protein 61 (CYR61) and metastasis associated in colon cancer (MACC1) protein promoted human colorectal cancer (CRC) cell metastasis and closely related to the patient's prognosis in colorectal cancer. The purpose of this article is to investigate whether CYR61 and MACC1 can serve as dual potential targets for gene therapy of human CRC. In this study, microRNA (miRNA) targeting for both CYR61 and MACC1 was used to investigate the mechanism and therapeutic effects for CRC cells and mice with CRC. We observed that silencing miRNA for CYR61 and MACC1 inhibited the epithelial-mesenchymal transition (EMT) process, and co-treatment strengthened this effect. MTT assay showed that the growth of colorectal tumor cells was decreased due to miRNA treatment. Apoptosis assay revealed that miRNA for CYR61 and MACC1 promoted CRC cells apoptotic. The animals' study results showed that the expression levels of CYR61 and MACC1 were significantly decreased after miRNA-100 and miRNA-143 treatment, respectively. The expression levels of apoptosis-promoting protein were increased significantly after treatment with miRNA-100 and miRNA-143, which suggested that both miRNA-100 and miRNA-143 may induce apoptosis by mitochondria-dependent pathway. In addition, metastasis and invasion assays showed that miRNA-100 and miRNA-143 treatment inhibited obviously migratory and invasive abilities of CRC cells. Furthermore, our data also showed that the tumor growth was significantly inhibited and survival rate of tumor-bearing mice was greatly improved by common treatments of miRNA-100 and miRNA-143. In conclusion, the abilities of apoptosis, metastasis, and invasion in CRC tumor cells were significantly suppressed by miRNA-100 and miRNA-143 targeting CYR61 and MACC1, respectively. As a result, CYR61 and MACC1 may serve as potential targets for gene therapy in human CRC treatments.

Influence of perineural invasion in predicting overall survival and disease-free survival in patients With locally advanced gastric cancer

BACKGROUND

The aim of the present study was to evaluate the prognostic significance of perineural invasion (PNI) in locally advanced gastric cancer patients who underwent D2 gastrectomy and adjuvant chemotherapy.

METHODS

The records of a series of 103 patients undergoing D2 gastrectomy with curative intent combined with adjuvant chemotherapy from January 2004 to December 2014 were retrospectively reviewed.

RESULTS

PNI was positive in 47 (45.6%) specimens. The 1-, 3-, and 5-year overall survival rates were 81%, 55%, and 42%, respectively. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 76%, 57%, and 49%, respectively. A multivariate analysis showed that age number of positive lymph nodes, T stage, and PNI were independently associated with overall survival. Regarding DFS, the multivariate analysis showed that only PNI was independently associated with DFS.

CONCLUSIONS

PNI and T stage and positive lymph nodes are independent markers of poor prognosis in patients with gastric cancer. PNI should be incorporated in the postoperative staging system for planning follow-up after surgery and in our opinion to propose more aggressive postoperative therapies in PNI-positive patients.

Evaluation of the association between perineural invasion and clinical and histopathological features of cervical cancer

Perineural invasion (PNI) has been investigated as a new prognostic factor in a number of carcinomas. However, studies on PNI in cervical cancer are limited, and inconsistent conclusions have been reported by different groups. The aim of the present study was to analyze the relationship between perineural invasion (PNI) and clinical and histopathological features of cervical cancer, and to evaluate the clinical significance of PNI of cervical cancer. Retrospective review identified 206 patients with cervical cancer who underwent radical hysterectomy plus pelvic lymphadenectomy between December 2012 and August 2014. The association between PNI and clinical and histopathological features of cervical cancer and post-operative radiotherapy was evaluated based on univariate and multivariate analyses. PNI of cervical cancer was identified in 33 of 206 (16%) cervical cancer patients. Univariate analysis demonstrated that PNI was associated with clinical stage, tumor grade, tumor size, depth of invasion, lymphovascular space invasion (LVSI), and lymph node metastasis (P<0.05), but not associated with age and histopathological types (P>0.05). Multivariate analysis suggests that LVSI and lymph node metastasis were associated with PNI of cervical cancer (P<0.05). In addition, post-operative radiotherapy was significantly more recommended for patients with PNI than those without PNI (P<0.001). In conclusion, PNI of cervical cancer is associated with LVSI and lymph node metastasis and can be used as an index for the determination of post-operative radiotherapy for cervical cancer patients.

The Prognostic Nutritional Index Predicts Survival and Identifies Aggressiveness of Gastric Cancer

Nutritional status has been associated with long-term outcomes in cancer patients. The prognostic nutritional index (PNI) is calculated by serum albumin concentration and absolute lymphocyte count, and it may be a surrogate biomarker for nutritional status and possibly predicts overall survival (OS) of gastric cancer. We evaluated the value of the PNI as a predictor for disease-free survival (DFS) in addition to OS in a cohort of 314 gastric cancer patients who underwent curative surgical resection. There were 77 patients in PNI-low group (PNI ≤ 47.3) and 237 patients in PNI-high group (PNI > 47.3). With a median follow-up of 36.5 mo, 5-yr DFS rates in PNI-low group and PNI-high group were 63.5% and 83.6% and 5-yr OS rates in PNI-low group and PNI-high group were 63.5% and 88.4%, respectively (DFS, P < 0.0001; OS, P < 0.0001). In the multivariate analysis, the only predictors for DFS were PNI, tumor-node-metastasis (TNM) stage, and perineural invasion, whereas the only predictors for OS were PNI, age, TNM stage, and perineural invasion. In addition, the PNI was independent of various inflammatory markers. In conclusion, the PNI is an independent prognostic factor for both DFS and OS, and provides additional prognostic information beyond pathologic parameters.

Perineural Invasion Is an Independent Pathologic Indicator of Recurrence in Vulvar Squamous Cell Carcinoma

OBJECTIVES

Vulvar squamous cell carcinoma (vSCC) is a gynecologic malignancy diagnosed in nearly 4500 women in the United States each year. Current criteria for treatment planning provide inadequate assessment of aggressive vSCC cases, resulting in insufficient use of adjuvant treatments and high rates of vSCC recurrence. Perineural invasion (PNI) is a pathologic feature inconsistently included in the assessment of vSCC, because its relevance to clinical outcomes in these women is not well defined. The purpose of this study was to determine the association between PNI and relevant clinical parameters such as recurrence.

METHODS

A total of 103 cases of vSCC were evaluated for PNI using pathology report review and immunohistochemistry dual-chromogen staining for S100 and AE1/3. Medical records were reviewed for clinical and follow-up data. Data were analyzed using univariate and multivariate logistic regression statistical methods.

RESULTS

Patients with vSCC containing PNI had a greater risk for cancer recurrence than those whose tumors did not contain PNI (odds ratio=2.8, P=0.0290). There was no significant correlation between the presence of PNI and nodal involvement, stage, or lymphovascular invasion. Tumors with PNI had greater depth of invasion (DOI) (P=0.0047); however, DOI was not associated with recurrence (P=0.2220). When analyzed using a multivariable logistic regression model, PNI was an independent predictor of recurrence in vSCC (adjusted odds ratio=2.613, P=0.045).

CONCLUSIONS

PNI is an independent indicator of risk for recurrence in vSCC. The association of PNI with increased risk for recurrence, independent of DOI, nodal involvement, lymphovascular invasion, or stage, should encourage practicing pathologists to thoroughly search for and report the presence of PNI in vSCC.