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

Nerve-tumor crosstalk in tumor microenvironment: From tumor initiation and progression to clinical implications

The autonomic nerve system (ANS) innervates organs and tissues throughout the body and maintains functional balance among various systems. Further investigations have shown that excessive activation of ANS not only causes disruption of homeostasis, but also may promote tumor formation. In addition, the dynamic interaction between nerve and tumor cells in the tumor microenvironment also regulate tumor progression. On the one hand, nerves are passively invaded by tumor cells, that is, perineural invasion (PNI). On the other hand, compared with normal tissues, tumor tissues are subject to more abundant innervation, and nerves can influence tumor progression through regulating tumor proliferation, metastasis and drug resistance. A large number of studies have shown that nerve-tumor crosstalk, including PNI and innervation, is closely related to the prognosis of patients, and contributes to the formation of cancer pain, which significantly deteriorates the quality of life for patients. These findings suggest that nerve-tumor crosstalk represents a potential target for anti-tumor therapies and the management of cancer pain in the future. In this review, we systematically describe the mechanism by which nerve-tumor crosstalk regulates tumorigenesis and progression.

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.

Preoperative prediction of perineural invasion and lymphovascular invasion with CT radiomics in gastric cancer

Objectives

To determine whether contrast-enhanced CT radiomics features can preoperatively predict lymphovascular invasion (LVI) and perineural invasion (PNI) in gastric cancer (GC).

Methods

A total of 148 patients were included in the LVI group, and 143 patients were included in the PNI group. Three predictive models were constructed, including clinical, radiomics, and combined models. A nomogram was developed with clinical risk factors to predict LVI and PNI status. The predictive performance of the three models was mainly evaluated using the mean area under the curve (AUC). The performance of three predictive models was assessed concerning calibration and clinical usefulness.

Results

In the LVI group, the predictive power of the combined model (AUC=0.871, 0.822) outperformed the clinical model (AUC=0.792, 0.728) and the radiomics model (AUC=0.792, 0.728) in both the training and testing cohorts. In the PNI group, the combined model (AUC=0.834, 0.828) also had better predictive power than the clinical model (AUC=0.764, 0.632) and the radiomics model (AUC=0.764, 0.632) in both the training and testing cohorts. The combined models also showed good calibration and clinical usefulness for LVI and PNI prediction.

Conclusion

CECT-based radiomics analysis might serve as a non-invasive method to predict LVI and PNI status in GC.

Correlation Analysis Between Tumor Deposit and Clinicopathologic Characteristics and Prognosis of Gastric Cancer: A Multicenter Retrospective Study

BACKGROUND

The mechanism underlying the formation of gastric tumor deposits (TDs) is unclear. We aimed to explore the risk factors for the formation and prognostic value of TDs.

METHODS

This retrospective analysis included 781 locally advanced gastric cancer (LAGC) patients from four medical institutions in China, from June 2014 to June 2018. The risk factors for TD formation and prognostic value were determined through univariate and multivariate analyses.

RESULTS

Univariate analysis revealed that TD positivity was closely related to tumor diameter, Borrmann classification, differentiation degree, pT stage, pN stage, pTNM stage, and nerve and vascular invasion (p < 0.05). Multivariate logistic regression revealed that tumor diameter ≥ 5 cm (odds ratio [OR] 1.836, 95% confidence interval [CI] 1.165-2.894, p = 0.009) and vascular invasion (OR 2.152, 95% CI 1.349-3.433, p = 0.001) were independent risk factors for TD positivity. Multivariate Cox analysis revealed that TD positivity (OR 1.533, 95% CI 1.101-2.134, p = 0.011), tumor diameter ≥ 5 cm (OR 1.831, 95% CI 1.319-2.541, p < 0.001), pT4a stage (OR 1.652, 95% CI 1.144-2.386, p = 0.007), and vascular invasion (OR 1.458, 95% CI 1.059-2.008, p = 0.021) were independent risk factors for GC prognosis. The 5-year overall and disease-free survival of the TD-positive group showed significant effects among patients in the pT4a and pN3b stages (p < 0.05).

CONCLUSIONS

TDs are closely related to tumor diameter and vascular invasion in LAGC patients, and TD positivity is an independent prognostic factor for LAGC patients, especially those at pT4a and pN3b stages.

The nerve cells in gastrointestinal cancers: from molecular mechanisms to clinical intervention

Gastrointestinal (GI) cancer is a formidable malignancy with significant morbidity and mortality rates. Recent studies have shed light on the complex interplay between the nervous system and the GI system, influencing various aspects of GI tumorigenesis, such as the malignance of cancer cells, the conformation of tumor microenvironment (TME), and the resistance to chemotherapies. The discussion in this review first focused on exploring the intricate details of the biological function of the nervous system in the development of the GI tract and the progression of tumors within it. Meanwhile, the cancer cell-originated feedback regulation on the nervous system is revealed to play a crucial role in the growth and development of nerve cells within tumor tissues. This interaction is vital for understanding the complex relationship between the nervous system and GI oncogenesis. Additionally, the study identified various components within the TME that possess a significant influence on the occurrence and progression of GI cancer, including microbiota, immune cells, and fibroblasts. Moreover, we highlighted the transformation relationship between non-neuronal cells and neuronal cells during GI cancer progression, inspiring the development of strategies for nervous system-guided anti-tumor drugs. By further elucidating the deep mechanism of various neuroregulatory signals and neuronal intervention, we underlined the potential of these targeted drugs translating into effective therapies for GI cancer treatment. In summary, this review provides an overview of the mechanisms of neuromodulation and explores potential therapeutic opportunities, providing insights into the understanding and management of GI cancers.

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.

Neural Invasion is an Independent Prognostic Factor in Young and Lymph Node Negative Gastric Cancer Patients Underwent Curative Gastrectomy

BACKGROUND

The prognostic significance of neural invasion (NI) in gastric cancer (GC) has not been established. This study is to investigate the characteristic and prognostic value of NI in GC.

METHODS

592 patients who had undergone gastrectomy for GC were retrospectively analyzed. NI was defined when cancer cells infiltrated into the perineurium or neural fascicles by hematoxylin and eosin staining of surgical specimens. NI and the other clinical factors were analyzed.

RESULTS

NI was detected in 270 of the 592 patients. NI was associated with tumor size, site, depth of invasion, lymph node metastasis, TNM stage, D dissection, tumor differentiation, Lauren classification, and blood vessel invasion. NI was associated with the overall survival. Multivariate analysis indicated that NI was not an independent prognostic factor for total patients, while NI independently predicted prognosis for age < 60 and lymph node metastasis negative patients by subgroup analysis. Concomitant existence of NI with tumor size ≥3cm, TNM stage III, or diffused Lauren classification independently predicted prognosis.

CONCLUSIONS

The frequency of NI is high in GC patients and increases with disease progression. NI is related to poor survival in GC patients who underwent curative gastrectomy and provides independent prognostic value for young and lymph node metastasis negative patients.

Enteric neuro-immune interactions in intestinal health and disease

The enteric nervous system is an autonomous neuronal circuit that regulates many processes far beyond the peristalsis in the gastro-intestinal tract. This circuit, consisting of enteric neurons and enteric glial cells, can engage in many intercellular interactions shaping the homeostatic microenvironment in the gut. Perhaps the most well documented interactions taking place, are the intestinal neuro-immune interactions which are essential for the fine-tuning of oral tolerance. In the context of intestinal disease, compelling evidence demonstrates both protective and detrimental roles for this bidirectional neuro-immune signaling. This review discusses the different immune cell types that are recognized to engage in neuronal crosstalk during intestinal health and disease. Highlighting the molecular pathways involved in the neuro-immune interactions might inspire novel strategies to target intestinal disease.

Development of an in vivo murine model of perineural invasion and spread of cutaneous squamous cell carcinoma of the head and neck

Introduction

Cutaneous squamous cell carcinoma of the head and neck (cSCCHN) can metastasize by invading nerves and spread toward the central nervous system. This metastatic process is called perineural invasion (PNI) and spread (PNS). An in vivo sciatic nerve mouse model is used for cSCCHN PNI/PNS. Here we describe a complementary whisker pad model which allows for molecular studies investigating drivers of PNI/PNS in the head and neck environment.

Methods

A431 cells were injected into the whisker pads of BALB/c Foxn1nu and NSG-A2 mice. Tumor progression was monitored by bioluminescence imaging and primary tumor resection was performed. PNI was detected by H&E and IHC. Tumor growth and PNI were assessed with inducible ablation of LOXL2.

Results

The rate of PNI development in mice was 10%-28.6%. Tumors exhibited PNI/PNS reminiscent of the morphology seen in the human disease. Our model's utility was demonstrated with inducible ablation of LOXL2 reducing primary tumor growth and PNI.

Discussion

This model consists in a feasible way to test molecular characteristics and potential therapies, offers to close a gap in the described in vivo methods for PNI/PNS of cSCCHN and has uses in concert with the established sciatic nerve model.

Analysis of influencing factors of nerve invasion in locally advanced gastric cancer

OBJECTIVES

Accurate preoperative diagnosis of locally advanced gastric cancer (GC) with nerve invasion is very important for guiding the clinical formulation of a reasonable treatment plan, improving treatment efficacy, and improving prognosis. The present study sought to analyze and evaluate the clinicopathological features of locally advanced GC, and to explore the risk factors associated with the state of nerve invasion.

METHODS

The clinicopathological data of 296 patients with locally advanced GC were retrospectively analyzed in our hospital from July 2011 to December 2020 who underwent radical gastrectomy. PNI is defined as a tumor close to the nerve and involving at least 33% of its circumference or tumor cells within any of the 3 layers of the nerve sheath. The patient's age, gender, tumor location, T stage, N stage, TNM stage, degree of differentiation, Lauren classification, microvascular invasion, as well as TAP, AFP, CEA, CA125, CA199, CA724, CA153, tumor thickness, longest diameter, and plain CT value, arterial phase CT value, venous phase CT value, arterial phase enhancement rate, venous phase enhancement rate were assessed.

RESULTS

A total of 296 patients with locally advanced GC were included, and 226 (76.35%) were positive for nerve invasion. Univariate analysis showed that tumor T stage, N stage, TNM stage, Lauren classification, tumor thickness, and longest diameter were related to the state of nerve invasion (P < 0.05). Multivariate analysis showed that tumor TNM stage was an independent risk factor for nerve invasion (OR 0.393, 95%CI 0.165-0.939, P = 0.036).

CONCLUSIONS

Tumor TNM stage is an independent risk factor for nerve invasion (+) in patients with locally advanced GC. Patients at high risk of nerve invasion should be followed closely and, if necessary, performed pathological examinations.

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.

Expectation-maximization algorithm leads to domain adaptation for a perineural invasion and nerve extraction task in whole slide digital pathology images

In addition to lymphatic and vascular channels, tumor cells can also spread via nerves, i.e., perineural invasion (PNI). PNI serves as an independent prognostic indicator in many malignancies. As a result, identifying and determining the extent of PNI is an important yet extremely tedious task in surgical pathology. In this work, we present a computational approach to extract nerves and PNI from whole slide histopathology images. We make manual annotations on selected prostate cancer slides once but then apply the trained model for nerve segmentation to both prostate cancer slides and head and neck cancer slides. For the purpose of multi-domain learning/prediction and investigation on the generalization capability of deep neural network, an expectation-maximization (EM)-based domain adaptation approach is proposed to improve the segmentation performance, in particular for the head and neck cancer slides. Experiments are conducted to demonstrate the segmentation performances. The average Dice coefficient for prostate cancer slides is 0.82 and 0.79 for head and neck cancer slides. Comparisons are then made for segmentations with and without the proposed EM-based domain adaptation on prostate cancer and head and neck cancer whole slide histopathology images from The Cancer Genome Atlas (TCGA) database and significant improvements are observed.

The GAL/GALR2 axis promotes the perineural invasion of salivary adenoid cystic carcinoma via epithelial-to-mesenchymal transition

BACKGROUND

Perineural invasion (PNI) is a typical pathological characteristic of salivary adenoid cystic carcinoma (SACC) and other neurotrophic cancers. The mechanism of the neural microenvironment controlling tumor progression during the PNI process is unclear. In the present study, we investigated the role and molecular mechanisms of nerve-derived neuropeptide galanin (GAL) and its receptor (GALR2) in the regulation of PNI in SACC.

METHODS

Immunohistochemistry staining and clinical association studies were performed to analyze the expression of GAL and GALR2 in SACC tissues and their clinical value. Dorsal root ganglion or SH-SY5Y cells were co-cultured with SACC cells in vitro to simulate the interactions between the neural microenvironment and tumor cells, and a series of assays including transcriptome sequencing, Western blot, and Transwell were performed to investigate the role and molecular mechanism of GAL and GALR2 in the regulation of SACC cells. Moreover, both the in vitro and in vivo PNI models were established to assess the potential PNI-specific therapeutic effects by blocking the GAL/GALR2 axis.

RESULTS

GAL and GALR2 were highly expressed in SACC tissues, and were associated with PNI and poor prognosis in SACC patients (p < 0.05). Nerve-derived GAL activated GALR2 expression in SACC cells and induced epithelial-to-mesenchymal transition (EMT) in SACC cells. Adding human recombinant GAL to the co-culture system promoted the proliferation, migration, and invasion of SACC cells significantly, but inhibited the apoptosis of SACC cells. Adding M871, a specific antagonist of GALR2, significantly blocked the above effects (p < 0.05) and inhibited the PNI of SACC cells in vitro and in vivo (p < 0.05).

CONCLUSIONS

This study demonstrated that nerve-derived GAL activated GALR2 expression, and promoted EMT in SACC cells, thereby enhancing the PNI process. Interruption of the GAL/GALR2 axis might be a novel strategy for anti-PNI therapy for SACC.

Neurons as stromal drivers of nervous system cancer formation and progression

Similar to their pivotal roles in nervous system development, neurons have emerged as critical regulators of cancer initiation, maintenance, and progression. Focusing on nervous system tumors, we describe the normal relationships between neurons and other cell types relevant to normal nerve function, and discuss how disruptions of these interactions promote tumor evolution, focusing on electrical (gap junctions) and chemical (synaptic) coupling, as well as the establishment of new paracrine relationships. We also review how neuron-tumor communication contributes to some of the complications of cancer, including neuropathy, chemobrain, seizures, and pain. Finally, we consider the implications of cancer neuroscience in establishing risk for tumor penetrance and in the design of future anti-tumoral treatments.

Tumor Characteristics Associated with Lymph Node Metastasis and Prognosis in Patients with ERBB2-Positive Gastric Cancer

Gastric cancers (GCs) that express human erb-b2 receptor tyrosine kinase 2 (ERBB2, also known as HER2) account for 7.3%–20.2% of GCs. The pathological and prognostic factors associated with lymph node metastasis of such tumors are still unclear. Therefore, we aimed to identify the risk factors for lymph node metastasis and prognostic factors of patients with ERBB2-positive GC. We conducted a retrospective analysis of pathological specimens after D2 radical surgery for locally advanced GC and D1+ surgery performed for early GC in our hospital from January 2015 to December 2018. Patients with ERBB2-positive GC were selected and the potential risk factors for lymph node metastasis and potential factors affecting prognosis were evaluated. Among 1,124 GC patients, 122 diagnosed with ERBB2-positive GC were included in the study. We found that risk factors for lymph node metastasis included tumor size (hazard ratio (HR)- 6.213, 95% confidence interval (CI)- 2.097–18.407, p = 0.001), neural invasion (HR- 2.876, 95% CI - 1.011–8.184, p = 0.048), and vascular invasion (HR- 16.881, 95% CI - 5.207–54.727, p < 0.001). T stage (HR- 4.615, 95% CI - 2.182–9.759, p < 0.001) and vascular invasion (HR- 3.036, 95% CI - 1.369–6.736, p = 0.006) were significant prognostic variables. These findings shed new light on the pathology and prognosis of patients with ERBB2-positive GC.

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.

The value of 18F-FDG PET/CT-based radiomics in predicting perineural invasion and outcome in non-metastatic colorectal cancer

PURPOSE

Perineural invasion (PNI) has been recognized as an important prognosis factor in patients with colorectal cancer (CRC). The purpose of this retrospective study was to investigate the value of ¹⁸F-FDG PET/CT-based radiomics integrating clinical information, PET/CT features, and metabolic parameters for preoperatively predicting PNI and outcome in non-metastatic CRC and establish an easy-to-use nomogram.

METHODS

A total of 131 patients with non-metastatic CRC who undergo PET/CT scan were retrospectively enrolled. Univariate analysis was used to compare the differences between PNI-present and PNI-absent groups. Multivariate logistic regression was performed to select the independent predictors for PNI status. Akaike information criterion (AIC) was used to select the best prediction models for PNI status. CT radiomics signatures (RSs) and PET-RSs were selected by maximum relevance minimum redundancy (mRMR) and the least absolute shrinkage and selection operator algorithm (LASSO) regression and radiomics scores (Rad-scores) were calculated for each patient. The prediction models with or without Rad-score were established. According to the nomogram, nomogram scores (Nomo-scores) were calculated for each patient. The performance of different models was assessed with the area under the curve (AUC), specificity, and sensitivity. The clinical usefulness was assessed by decision curve (DCA). Multivariate Cox regression was used to selected independent predictors of progression-free survival (PFS).

RESULTS

Among all the clinical information, PET/CT features, and metabolic parameters, CEA, lymph node metastatic on PET/CT (N stage), and total lesion glycolysis (TLG) were independent predictors for PNI (p < 0.05). Six CT-RSs and 12 PET-RSs were selected as the most valuable factors to predict PNI. The Rad-score calculated with these RSs was significantly different between PNI-present and PNI-absent groups (p < 0.001). The AUC of the constructed model was 0.90 (95%CI: 0.83-0.97) in the training cohort and 0.80 (95%CI: 0.65-0.95) in the test cohort. The nomogram's predicting sensitivity was 0.84 and the specificity was 0.83 in the training cohort. The clinical model's predicting sensitivity and specificity were 0.66 and 0.85 in the training cohort, respectively. Besides, DCA showed that patients with non-metastatic CRC could get more benefit with our model. The results also indicated that N stage, PNI status, and the Nomo-score were independent predictors of PFS in patients with non-metastatic CRC.

CONCLUSION

The nomogram, integrating clinical data, PET/CT features, metabolic parameters, and radiomics, performs well in predicting PNI status and is associated with the outcome in patients with non-metastatic CRC.

Data Set for Reporting Carcinoma of the Stomach in Gastrectomy

Context.—

A standardized detailed surgical pathology report is the cornerstone of gastric cancer management.

Objective.—

To guide management and prognostication for patients with gastric carcinomas globally, the International Collaboration on Cancer Reporting aimed to produce an evidence-based international pathology reporting data set with a panel of globally recognized expert pathologists and clinicians.

Design.—

Based on published guidelines/data sets for gastric carcinomas, a working draft was developed by the chair of the expert panel of pathologists and clinicians. The draft was then circulated to the panel and discussed in a series of teleconferences and email communications until consensus was achieved. The draft data set was uploaded on the International Collaboration on Cancer Reporting Web site for public comment. The data set was reviewed in consideration of the feedback, and a final version was approved by the panel.

Results.—

This data set was developed for gastrectomy specimens for primary gastric carcinomas, including neuroendocrine carcinomas and mixed neuroendocrine-nonneuroendocrine neoplasms. Well-differentiated neuroendocrine tumors, nonepithelial malignancies, and secondary tumors were excluded from this data set. The final data set contains 15 core (required) elements and 8 noncore (recommended) elements. A commentary is provided for each element.

Conclusions.—

The International Collaboration on Cancer Reporting has published freely available, evidence-based data sets for gastric cancer reporting. Standardized reporting has been shown to improve patient care and facilitates data exchange and analysis for quality assurance, cancer epidemiology, and clinical and basic research.

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.

Clinicopathological factors associated with the presence of tumor deposits in resected gastric cancer patients

Purpose

The role of tumor deposits (TDs) in the staging of gastric cancer is currently debatable. TDs are defined as tumoral nodules in perigastric adipose tissue with no evidence of lymphatic, vascular, or neural structures. Clinicopathological factors related to the presence of TDs are not well defined. This study aimed to identify the clinicopathological factors associated with the presence of TDs in resected gastric cancer patients.

Materials and methods

This prospective study included patients diagnosed with gastric cancer and treated with D2 radical gastrectomy from January 2019 to January 2020. Univariate and multivariate analyses were performed to determine the factors related to the presence of TDs.

Results

A total of 111 patients were eligible and TDs were present in 31 of them (28%). In the univariate analysis, male gender (p = 0.027), tumor size ≥ 5cm (p = ≤0.001), serosa and adjacent organs invasion (pT4a and pT4b) (p = ≤0.001), ≥16 metastatic lymph nodes (pN3b) (p = ≤0.001), and TNM stage III tumors (p = ≤0.001) were significantly associated with the presence of TDs. The multivariate analysis showed that a tumors size ≥5 cm (OR = 3.69, 95% CI: 1.17-11.6), serosa and adjacent organs invasion (pT4a and pT4b) (OR = 3.78, 95% CI: 1.31-10.86) and ≥16 metastatic lymph nodes (pN3b) (OR = 3.21, 95%CI:1.06-9.7) were independent risk factors for the presence of TDs.

Conclusions

Larger tumors (tumor size ≥ 5cm), serosa and adjacent organs invasion (pT4 and pT4b), and ≥16 metastatic lymph nodes (pN3b) were independent risk factors for the presence of TDs.

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.

Concurrent lymphovascular and perineural invasion after preoperative therapy for gastric adenocarcinoma is associated with decreased survival

BACKGROUND AND OBJECTIVES

We sought to evaluate the impact of lymphovascular invasion (LVI) and perineural invasion (PNI) on survival outcomes in gastric cancer patients treated with preoperative therapy.

METHODS

Patients with gastric cancer treated with preoperative therapy and potentially curative resection were stratified according to the presence of LVI, PNI, or both. Kaplan-Meier and Cox regression analyses were used to evaluate the impact on overall survival (OS) and disease-free survival (DFS).

RESULTS

The study included 281 patients, of whom 93 (33%) had LVI, 69 (25%) had PNI, 51 (18%) had both LVI and PNI, and 170 (61%) had neither. LVI and PNI were each associated with higher ypT and ypN categories and more positive lymph nodes (all p < .001), associations that were emphasized with both factors present. On multivariable analyses, ypN (p < .001) and concurrent LVI/PNI (hazard ratio [HR]: 2.62; 95% confidence interval [CI]: 1.55-4.45; p = .001) were predictive of OS and DFS (ypN: p < .001; both LVI/PNI: HR: 2.27; 95% CI: 1.34-3.82; p = .002).

CONCLUSIONS

Gastric cancer patients with concurrent LVI and PNI after preoperative therapy have more advanced disease and worse survival outcomes than patients with neither or only one of these factors.

Prognostic effect of perineural invasion in successive years in patients with locally advanced gastric cancer

Aim

The present study evaluates the prognostic significance of perineural invasion (PNI) on 2-year, 5-year, and overall survival in patients undergoing gastrectomy and D2 lymphadenectomy due to locally advanced gastric cancer.

Materials and Methods

Included in the study were 231 patients who underwent surgery between November 2006 and October 2018 due to stage 1B and over locally advanced gastric cancer, whose records were reviewed retrospectively.

Statistical Analysis

The variables in the presence or absence of PNI were compared between the two groups with a Chi-square test, a Fisher's exact test, a likelihood ratio, and a Mann-Whitney U test. Overall survival data were evaluated with a Kaplan-Meier test. Prognostic factors were evaluated with a stepwise Cox regression analysis.

Results

PNI was identified in 167 (72.3%) of the patients. The 2-year, 5-year, and overall survival rates at the end of the follow-up period were 85.9%, 70.3%, and 64.1% in those without PNI, and 52.7%, 38.3%, and 36.5% in those with PNI, respectively. In a multivariate analysis, PNI appeared to be a significant prognostic factor for 2-year survival (P = 0.04) but had no effect on 5-year and overall survival.

Conclusions

Survival was shorter in patients with PNI than in patients without PNI, and PNI had no effect on overall survival, although it was found to be of prognostic significance for 2-year survival.

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.

A Holistic Perspective: Exosomes Shuttle between Nerves and Immune Cells in the Tumor Microenvironment

One of the limitations of cancer research has been the restricted focus on tumor cells and the omission of other non-malignant cells that are constitutive elements of this systemic disease. Current research is focused on the bidirectional communication between tumor cells and other components of the tumor microenvironment (TME), such as immune and endothelial cells, and nerves. A major success of this bidirectional approach has been the development of immunotherapy. Recently, a more complex landscape involving a multi-lateral communication between the non-malignant components of the TME started to emerge. A prime example is the interplay between immune and endothelial cells, which led to the approval of anti-vascular endothelial growth factor-therapy combined with immune checkpoint inhibitors and classical chemotherapy in non-small cell lung cancer. Hence, a paradigm shift approach is to characterize the crosstalk between different non-malignant components of the TME and understand their role in tumorigenesis. In this perspective, we discuss the interplay between nerves and immune cells within the TME. In particular, we focus on exosomes and microRNAs as a systemic, rapid and dynamic communication channel between tumor cells, nerves and immune cells contributing to cancer progression. Finally, we discuss how combinatorial therapies blocking this tumorigenic cross-talk could lead to improved outcomes for cancer patients.

Prognostic factors in stage I gastric cancer: A retrospective analysis

Purpose

The purpose of this research is to investigate the prognostic factors of patients with stage I gastric cancer (GC) and to determine whether adjuvant chemotherapy improves the prognosis for high-risk patients.

Methods

We performed a retrospective analysis at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, and HwaMei Hospital, University of Chinese Academy of Sciences from January 2001 to December 2015. Cox regression and Kaplan-Meier were used to evaluate the relationship between the patients’ clinicopathologic characteristics and prognosis.

Results

A total of 1,550 patients were eligible for the study. The 5-year disease-free survival (DFS) rate of all enrolled patients was 96.5%. The pT and pN stages were significantly associated with the prognosis. The 5-year DFS rates of the three subgroups (T1N0, T2N0, and T1N1) were 97.8%, 95.7%, and 90.5%, respectively (p < 0.001). In the T1N1 subgroup, patients not undergoing chemotherapy showed a lower 5-year DFS rate compared to those undergoing chemotherapy, although the difference was not statistically significant.

Conclusions

Both the pT and pN stages were closely associated with the prognosis of patients with stage I GC. We also found that the danger coefficient of the pN stage was higher than that of the pT stage, and that postoperative adjuvant chemotherapy might be a reasonable approach to improve outcomes of high-risk patients, particularly in the T1N1 group.

Minimal residual disease in advanced or metastatic solid cancers: The G0-G1 state and immunotherapy are key to unwinding cancer complexity

In the last decade, a large amount of research has focused on elucidating the mechanisms that account for homing disseminated cancer cells (DCCs) from solid tumours to distant organs, which successively progress to overt metastatic disease; this is currently incurable. A better understanding of DCC behaviour is expected to allow detectable metastasis prevention by more effectively targeting 'metastatic seeds before they sprout'. As DCC biology co-evolved with that of the primary tumour, and due to the many similarities between them, the term 'niche' has been borrowed from normal adult stem cells (ASCs) to define the site of DCC metastatic colonisation. Moreover, heterogeneity, survival, protection, stemness and plasticity as well as the prolonged G0-G1 dormant state in the metastatic niche have been the main aspects of intense investigation. Consistent with these findings, in solid cancers with minimal residual disease (MRD), it has been proposed to prolong adjuvant therapy by targeting specific molecular pathway(s) involving DCC dormancy. However, so far, few disappointing clinical data have been reported. As an alternative strategy, because immune-surveillance contributes to the steady state of the DCC population and likely to the G0-G1 state of cancer cells, we have used prolonged immune-modulatory cytostatic chemotherapy, active immune stimulation with an INF-β/IL-2 sequence or drugs inhibiting myeloid-derived suppressor cell (MDSC)/Treg-mediated immune suppression. This strategy, mainly aimed at boosting the immune response, is based on recent findings suggesting the downregulation of immune escape mechanisms as well as other principal hallmarks during the G0-G1 state and/or in MRD. Preliminary clinical and/or laboratory data suggest the efficacy of this strategy in gastrointestinal and some endocrine-dependent cancers. Following this, we propose therapeutic schedules to prevent DCC activation and proliferation in solid cancers at a high risk of relapse or as maintenance therapy in metastatic patients after complete response (CR) to conventional treatment.

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.

Nervous system and gastric cancer

The nervous system has been recently shown to exert impact on gastric cancer directly and indirectly. Gastric cancer cells invade nerve fibers to induce outgrowth and branching of neural cells, and nerve fibers in turn infiltrate into tumor microenvironment to promote progression of gastric cancer. Additionally, the neuro-immune interaction also plays an important role in gastric cancer development. The interplay of nerves and gastric cancer is mediated by many nervous system-associated factors, which can not only be synthesized and released by both cancer cells and nerve terminals, but also participate in regulation of many aspects of gastric cancer such as cell proliferation, angiogenesis, metastasis and recurrence. Furthermore, clinical researches indicate that some of these factors are significant diagnosis and prognosis biomarkers for gastric cancer. Herein, we reviewed recent advances and future prospects of the interaction between nervous system and gastric cancer.

Optimal management of resected gastric cancer

Although advances in medical treatment for gastric cancer (GC) have been made, surgery remains the mainstay of cure for patients with localized disease. Improvement in surgical modalities leads to increased chance of cure for resected patients, but a non-negligible number of patients eventually relapse. On this basis, it has been hypothesized that the addition of complementary systemic or local treatments (such as chemotherapy and radiotherapy) could help in improving patients' survival by reducing the risk of recurrence. Several studies have tried to identify the best approach in localized GC: some of them have assessed the role of perioperative chemotherapy [CT] with different drug combinations, while others have focused on the benefit obtained by addition of radiotherapy, whose role is still under investigation. In particular, the role of chemoradiotherapy, both in adjuvant and neoadjuvant settings, is still uncertain. In the last few years, several clinicopathological and molecular factors have been investigated and identified as potential prognostic markers in GC. Many of these factors could have influenced the outcome of patients receiving combined treatments in the abovementioned studies. Patients have not been generally distinguished by the site of disease (esophageal, gastric and junctional cancers) and surgical approach, making data difficult to be interpreted. The purpose of this review was to shed light on these highly controversial topics.

Wedge-shaped microfluidic chip for circulating tumor cells isolation and its clinical significance in gastric cancer

Background

Circulating tumor cells (CTCs) have great potential in both basic research and clinical application for the managements of cancer. However, the complicated fabrication processes and expensive materials of the existing CTCs isolation devices, to a large extent, limit their clinical translation and CTCs’ clinical value. Therefore, it remains to be urgently needed to develop a new platform for achieving CTCs detection with low-cost, mass-producible but high performance.

Methods

In the present study, we introduced a novel wedge-shaped microfluidic chip (named CTC-ΔChip) fabricated by two pieces of glass through wet etching and thermal bonding technique for CTCs isolation, which achieved CTCs enrichment by different size without cell surface expression markers and CTCs identification with three-color immunocytochemistry method (CK+/CD45−/Nucleus+). We validated the feasibility of CTC-ΔChip for detecting CTCs from different types of solid tumor. Furthermore, we applied the newly-developed platform to investigate the clinical significance of CTCs in gastric cancer (GC).

Results

Based on “label-free” characteristic, the capture efficiency of CTC-ΔChip can be as high as 93.7 ± 3.2% in DMEM and 91.0 ± 3.0% in whole blood sample under optimized conditions. Clinically, CTC-ΔChip exhibited the feasibility of detecting CTCs from different types of solid tumor, and it identified 7.30 ± 7.29 CTCs from 2 mL peripheral blood with a positive rate of 75% (30/40) in GC patients. Interestingly, we found that GC CTCs count was significantly correlated with multiple systemic inflammation indexes, including the lymphocyte count, platelet count, the level of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio. In addition, we also found that both the positivity rate and CTCs count were significantly associated with multiple clinicopathology parameters.

Conclusions

Our novel CTC-ΔChip shows high performance for detecting CTCs from less volume of blood samples of cancer patients and important clinical significance in GC. Owing to the advantages of low-cost and mass-producible, CTC-ΔChip holds great potential of clinical application for cancer therapeutic guidance and prognostic monitoring in the future.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1521-8) contains supplementary material, which is available to authorized users.