Perineural Invasion is a Strong Prognostic Factor in Colorectal Cancer: A Systematic Review.Am J Surg Pathol. 2016;40:103-112. [PMID: 26426380 DOI: 10.1097/PAS.0000000000000518]

Lymphovascular invasion, perineural invasion, and tumor budding are prognostic factors for stage I colon cancer recurrence

BACKGROUND

The diagnostic impact of lymphovascular invasion (LVI), perineural invasion (PNI), and tumor budding in stage I colon cancer is currently unknown. This study was conducted to evaluate the prognostic impact of LVI, PNI, and tumor budding in stage I colon cancer.

METHODS

From January 2008 to December 2013, 720 patients who underwent curative surgery and were diagnosed with stage I colon cancer were reviewed retrospectively. These patients were categorized into two groups based on LVI, PNI, and tumor budding: the no risk group (n = 566) and risk group (n = 154).

RESULTS

Median follow-up period was 103.5 months, and the 5-year disease-free survival rate of the risk group was significantly lower than that of the no risk group (p = 0.025). In multivariate analysis, only the risk group had prognostic factors for 5-year disease-free survival (p = 0.036). In addition, only differentiation was an independent predictor in the risk group (p = 0.009).

CONCLUSION

LVI, PNI, and tumor budding are strong prognostic factors for stage I colon cancer. Therefore, patients with positive LVI, PNI, or tumor budding should receive close follow-up and potentially be considered for chemotherapy.

Colon metal stents as a bridge to surgery had no significant effects on the perineural invasion: a retrospective study

Purpose

The long-term oncological effects of self-expandable metallic stent (SEMS) as a “bridge to surgery” are contradictory, and perineural invasion was supposed to be enhanced by the stenting. In this retrospective study, we compared the perineural invasion and the oncological outcomes between the stent as a bridge to surgery (SBTS)- and emergency surgery (ES)-treated patients to evaluate the results of stenting on the perineural invasion.

Methods

The clinical data of patients with acute intestinal obstruction caused by colorectal cancer from January 2013 to January 2017 were retrospectively collected. Forty-three patients underwent semi-elective curative resection after endoscopic SEMS insertion, and sixty-three underwent ES. The adverse events and long-term follow-up outcomes were assessed. The clinicopathological characteristics, perineural invasion rates, and survival rates were compared between the two patient groups.

Results

Stent insertion resulted in significantly lower stoma rate (32.6% vs 46%; P = 0.03), post-operative overall complication rate (11.6% vs 28.6%, P = 0.038), and total hospital stay (17.07 ± 5.544 days vs 20.48 ± 7.372 days, P = 0.042). Compared with the ES group, there was no significant increase in the incidence of peripheral invasion in the SBTS group (39.5% vs 47.6%, P = 0.411). No significant difference was noted in the survival rate and long-term prognosis between the SEMS and ES groups (P = 0.964). The technical success rate was 95.6%, and the clinical success rate was 97.7%.

Conclusions

Preoperative colon stenting was an effective transitional method for colorectal cancer patients with complete obstruction. Short-term stent implantation had no significant effect on perineural invasion in patients with CRC.

Development and validation of a nomogram to predict survival after curative resection of nonmetastatic colorectal cancer

Background

We aimed to develop a clinical applicable nomogram to predict overall survival (OS) for patients with curatively resected nonmetastatic colorectal cancer.

Methods

Records from a retrospective cohort of 846 patients with complete information were used to construct the nomogram. The nomogram was validated in a prospective cohort of 379 patients. The performance of the nomogram was evaluated with concordance index (c‐index), time‐dependent receiver operating characteristic (ROC) curves, calibration plots, and decision curve analyses for discrimination, accuracy, calibration ability, and clinical net benefits respectively, and further compared with AJCC 8th TNM staging and the MSKCC nomogram. Risk stratification based on nomogram scores was performed with recursive partitioning analysis.

Results

The nomogram incorporated age, Glasgow prognostic score, pretreatment carcinoembryonic antigen levels, T staging, N staging, number of harvested lymph nodes, and histological grade. Compared with the 8th AJCC staging and MSKCC model, the nomogram had a statistically higher c‐index (0.77, 95% CI: 0.73‐0.80), bigger areas under the time‐dependent ROC curves (AUC at 3 years: 79; at 5 years: 79), and improved clinical net benefits. Calibration plots revealed no deviations from reference lines. All results were reproducible in the validation cohort. Nomogram‐based risk stratification successfully discriminated patients within each AJCC stage (all log‐rank P < .05).

Conclusion

We established an accurate, reliable, and easy‐to‐use nomogram to predict OS after curative resection for nonmetastatic colorectal cancer (CRC). The nomogram outperformed the 8th AJCC staging and the MSKCC model and could aid in personalized treatment and follow‐up strategy for CRC patients.

Pathways of spread in rectal cancer: a reappraisal of the true routes to distant metastatic disease

Rectal cancer can spread in a number of ways which have been previously recognised and validated as prognostic markers. These routes of spread are not adequately recognised in the stage grouping of the tumour-node-metastasis system, which focuses predominantly on the depth of invasion and nodal status, thus limiting its prognostic accuracy. Tumour spread involving veins occurs in 40% of patients. Venous channels have greater direct access to distant sites by means of a vascular 'anatomical highway'. This rapid spread of tumour cells to distant metastatic sites by veins cannot occur by means of lymph node pathways. Thus, lymph nodes have been overestimated in their importance. Distinction between local tumour spread (lymph node metastases, perineural and lymphatic invasion) and tumour spread mediated by a direct vascular pathway to distant dissemination (extramural venous invasion and tumour deposits) must be made as the implications for prognosis and choice of treatment are not likely to be equal. Improved precision of radiological and pathological assessment is needed to scrutinise and carefully document each route of tumour spread. Only with this accurate information will it be possible to correctly weight each feature and develop a more prognostically accurate staging method that would allow separation of true high- and low-risk groups and subsequent improvements in patient care.

Weighted Gene Co-Expression Network Analysis Identified Cancer Cell Proliferation as a Common Phenomenon During Perineural Invasion

Purpose

Perineural invasion (PNI) is the neoplastic invasion of nerves by cancer cells, a process that may prove to be another metastatic route besides direct invasion, lymphatic spread, and vascular dissemination. Given the increasing incidence and association with poor prognosis, revealing the pathogenesis of perineural invasion is of great importance.

Materials and methods

Four datasets related to PNI were downloaded from the Gene Expression Omnibus database and used to construct weighted gene co-expression network analysis (WGCNA). The intersection of potential pathways obtained from further correlation and enrichment analyses of different datasets was validated by the coculture model of Schwann cells (SCs), flow cytometry and immunohistochemistry (IHC).

Results

GSE7055 and GSE86544 datasets were brought into the analysis for there were some significant modules related to PNI, while GSE103479 and GSE102238 datasets were excluded for insignificant differences. In total, 13,841 genes from GSE86544 and 10,809 genes from GSE7055 were used for WGCNA. As a consequence, 19 and 26 modules were generated, respectively. The purple module of GSE86544 and the dark gray module of GSE7055 were positively correlated with perineural invasion. Further correlation and enrichment analyses of genes from the two modules suggested that these genes were mainly enriched in cell cycle processes; especially, the terms S/G2/M phase were enriched. Three kinds of cells grew vigorously after coculture with SCs ex vivo. The Ki67 staining of the cervical cancer samples revealed that the Ki67 index of cancer cells surrounding nerves was higher than of those distant ones.

Conclusion

Our work has identified cancer cell proliferation as a common response to neural cancerous microenvironments, proving a foundation for cancer cell colonization and metastasis.

Comprehensive Comparative Analysis of Prognostic Value of Systemic Inflammatory Biomarkers for Patients with Stage II/III Colon Cancer

BACKGROUND

Among numerous systemic inflammatory biomarkers, it remains unclear which is the most prognostic for patients with stage II/III colon cancer. We aimed to compare the prognostic significance of systemic inflammatory biomarkers among patients with stage II/III colon cancer.

METHODS

We included 1303 patients with stage II/III colon cancer who underwent potentially curative resection from July 2004 to December 2013. Sixteen systemic inflammatory biomarkers-derived from combinations of neutrophils, lymphocytes, monocytes, platelets, C-reactive protein (CRP), and albumin-were compared to identify the biomarker most associated with overall survival (OS) and disease-free survival (DFS) using receiver operating characteristic (ROC) curve analysis.

RESULTS

Nine inflammatory biomarkers were predictive for OS, among which lymphocyte-to-CRP ratio (LCR), CRP-to-albumin ratio (CAR), neutrophil × CRP, monocyte × CRP, and platelet × CRP were also predictive for DFS. Among these five inflammatory biomarkers, the area under the curve (AUC) value was highest (0.630) for LCR, being significantly higher than that for neutrophil × CRP (P = 0.010), monocyte × CRP (P = 0.007), or platelet × CRP (P = 0.010) for OS. When the prognostic impact of LCR and CAR were analyzed by multivariate analysis, only LCR was an independent predictor of both OS [hazard ratio (HR), 1.77; 95% confidence interval (CI), 1.23-2.60; P = 0.002] and DFS (HR, 1.29; 95% CI, 1.00-1.66; P = 0.048).

CONCLUSIONS

LCR may be the most useful predictive factor for OS and DFS in patients with stage II or III colon cancer.

Adenocarcinoma with mixed subtypes is a rare but aggressive histologic subtype in colorectal cancer

Background

Although numerous studies have investigated the clinicopathologic and prognostic relevance of mucinous adenocarcinoma (MAC) and signet-ring cell carcinoma (SRCC) compared with classic adenocarcinoma (CA), little is known about the prognosis of adenocarcinoma with mixed subtypes (AM) and the differences among these four subtypes.

Methods

The statistics of colorectal cancer registered in the Surveillance, Epidemiology and End Results (SEER) database were retrieved and analyzed. We also compared the clinicopathologic and prognostic relevance between CA, SRCC, MAC, and AM.

Results

The frequencies of these four subtypes were 69.9% (CA, n = 15,812), 25.1% (MAC, n = 5689), 3.6% (SRCC, n = 814) and 1.4% (AM, n = 321), respectively. All of MAC, SRCC, and AM were significantly related with aggressive features. Only SRCC and AM were identified as independent poor prognostic markers for overall survival by multivariate analysis. The aggressiveness of AM was between MAC and SRCC according to the clinicopathologic associations. The prognosis of AM was significantly worse than MAC but comparable with SRCC.

Conclusions

We confirmed the clinicopathologic relevance with aggressive features of MAC and SRCC, as well as poor prognostic relevance of SRCC by analyzing a large study population data set. Furthermore, we identified AM as a rare but aggressive histologic subtype in colorectal cancer, to which particular attention should be given in clinical practice.

Schwann cells shape the neuro-immune environs and control cancer progression

At present, significant experimental and clinical data confirm the active involvement of the peripheral nervous system (PNS) in different phases of cancer development and progression. Most of the research effort focuses on the impact of distinct neuronal types, e.g., adrenergic, cholinergic, dopaminergic, etc. in carcinogenesis, generally ignoring neuroglia. The very fact that these cells far outnumber the other cellular types may also play an important role worthy of study in this context. The most prevalent neuroglia within the PNS consists of Schwann cells (SCs). These cells play a substantial role in maintaining homeostasis within the nervous system. They possess distinct immunomodulatory, inflammatory and regenerative capacities-also, one should consider their broad distribution throughout the body; this makes them a perfect target for malignant cells during the initial stages of cancer development and the very formation of the tumor microenvironment itself. We show that SCs in the tumor milieu attract different subsets of immune regulators and augment their ability to suppress effector T cells. SCs may also up-regulate invasiveness of tumor cells and support metastatic disease. We outline the interactive potential of SCs juxtaposed with cancerous cells, referring to data from various external sources alongside data of our own.

Tumour budding predicts increased recurrence after curative resection for T2N0 colorectal cancer

Background

Tumour budding is defined as the presence of a cluster of fewer than 5 cells along the invasive margin. It may confer a worse prognosis in colorectal cancer, but its importance in pT2N0 colorectal cancer is unknown. This study aimed to determine the prognostic value of tumour budding in pT2N0 colorectal cancer.

Methods

This was a retrospective cohort study with prospective assessment of tumour budding by 2 pathologists. We included all patients who underwent elective curative resection for pT2N0 colorectal cancer except those with hereditary colorectal cancer syndromes, inflammatory bowel disease or positive resection margins, those who received neoadjuvant or adjuvant therapy and those who died within 90 days of operation. Patients were classified as having high-grade tumour budding (≥ 10 budding foci per high-power field) or low-grade tumour budding (< 9 budding foci per high-power field). The main outcome measure was locoregional or distant recurrence.

Results

Of 85 patients, 36 had high-grade tumour budding and 49 had low-grade tumour budding. The overall recurrence rate was 11% (9/85) and median follow-up was 41.0 months (interquartile range 22.0–68.0). Interrater reliability for tumour budding assessment was excellent (κ = 0.86, 95% confidence interval [CI] 0.76–0.96). There were more recurrences in patients with high-grade tumour budding (7/36, 19.4% v. 2/49, 4.1%; p = 0.020). On multivariate analysis, after we adjusted for confounders, the presence of high-grade tumour budding was independently associated with recurrence (hazard ratio 5.11, 95% CI 1.01–25.9).

Conclusion

Tumour budding was independently associated with increased recurrence after pT2N0 colorectal cancer resection. It offers additional prognostic information that may affect treatment strategy.

Perineural Invasion Is a Prognostic but not a Predictive Factor in Nonmetastatic Colon Cancer

BACKGROUND

Perineural invasion is associated with adverse oncological outcomes in colorectal cancer. However, data regarding the prognostic and predictive impact in colon cancer are scarce.

OBJECTIVE

This study aims to clarify the role of perineural invasion in patients with nonmetastatic colon cancer.

DESIGN

This study is a retrospective review of a prospectively maintained database.

SETTINGS

This study took place at a tertiary medical center.

PATIENTS

Patients with stage I to III colon cancer who underwent elective surgery at our tertiary center between 2004 and 2015 (n = 1145) were included.

MEAN OUTCOME MEASURES

The primary long-term outcomes include disease-free survival, disease-specific survival, and overall survival. Differences were determined by multivariate Cox regression models adjusted for stage and potential confounders.

RESULTS

Perineural invasion was identified in 215 patients (18.8%) and associated with emergency procedures, male sex, and advanced disease. Histopathological features including lymphatic and extramural vascular invasion, poor differentiation, and infiltrating tumor borders were correlated with perineural invasion. Compared with patients with perineural invasion-negative tumors, patients who had perineural invasion-positive tumors had worse disease-free, overall, and disease-specific survival (all p < 0.001). Moreover, patients with perineural invasion-positive node-negative disease had worse overall survival than patients with perineural invasion-negative node-positive disease (p < 0.001). After adjustment, perineural invasion remained significantly associated with worse disease-free survival (HR, 1.45; 95% CI, 1.03-2.03; p = 0.033), worse overall survival (HR, 1.75; 95% CI, 1.33-2.31; p < 0.001), and worse disease-specific survival (HR, 1.52; 95% CI, 1.00-2.30; p = 0.048). However, we did not find a significant predictive response with adjuvant chemotherapy in perineural invasion-positive node-negative tumors (HR, 2.10; 95% CI, 0.80-5.51; p = 0.122). The predictive value was only demonstrated in stage III disease with a significant impaired overall survival in patients with perineural invasion-positive tumors who did not receive adjuvant therapy (HR, 0.23; 95% CI, 0.13-0.40; p < 0.001).

LIMITATIONS

This study was limited by its retrospective design.

CONCLUSION

Our study confirms the prognostic value of perineural invasion in stage I to II and III colon cancer. However, patients with node-negative disease and perineural invasion did not significantly benefit from adjuvant therapy. More information regarding postoperative treatment in node-negative perineural invasion-positive colon cancer is required. See Video Abstract at http://links.lww.com/DCR/A988. LA INVASIÓN PERINEURAL COMO FACTOR PRONÓSTICO NO PREDICTIVO EN EL CÁNCER DE COLON NO METASTÁSICO: La invasión perineural se encuentra asociada a resultados oncológicos adversos en casos de cáncer colorrectal. Sin embargo, los datos sobre el impacto pronóstico y predictivo en caso de cáncer de colon son pocos.

OBJETIVO

Definir el papel de la invasión perineural en pacientes con cáncer de colon no metastásico. DISEÑO:: Revisión retrospectiva de una base de datos alimentada prospectivamente.

AJUSTES

Centro hospitalario de atención terciaria.

PACIENTES

Todos aquellos portadores de un cáncer de colon estadío I-III que se sometieron a cirugía electiva en nuestro centro entre 2004-2015 (n = 1145).

PRINCIPALES RESULTADOS

Los resultados a largo plazo incluyeron la supervivencia sin enfermedad, la supervivencia específica de la enfermedad y la supervivencia general. Las diferencias se determinaron mediante modelos de regresión multivariantes de Cox, ajustados para el control de factores de confusión durante el análisis por estratificación.

RESULTADOS

La invasión perineural fué identificada en 215 pacientes (18.8%) y se la asoció con procedimientos de emergencia, al género masculino y a la enfermedad avanzada. Las características histopatológicas que incluyeron la invasión vascular linfática y extramural, la diferenciación deficiente y los bordes tumorales infiltrantes se correlacionaron con la invasión perineural. Comparativamente con los tumores sin invasión perineural, los pacientes positivos a la invasión perineural tuvieron una peor supervivencia general, libre y específica de la enfermedad (todos p < 0.001). Asimismo, aquellos pacientes con invasion-perineural con ganglios negativos tuvieron una supervivencia global mucho peor que aquellos pacientes con ganglios positivos e invasión perineural negativa (p < 0.001). Después del ajuste, la invasión perineural se asoció significativamente con una peor supervivencia sin la enfermedad (HR, 1.45; IC 95%, 1.03-2.03; p = 0.033), supervivencia general (HR, 1.75; IC 95%, 1.33-2.31; p <0.001), así como con una peor supervivencia específica de la enfermedad (HR, 1.52; IC 95%, 1.00-2.30; p = 0.048). Sin embargo, no encontramos una respuesta predictiva significativa con quimioterapia adyuvante en los tumores acompañados de invasion-perineural con ganglios negativos (HR, 2.10; IC del 95%, 0.80-5.51; p = 0.122). El valor predictivo solo fué demostrado en aquellos casos de estadio III con un deterioro significativo de la supervivencia global en pacientes con tumores perineurales positivos a la invasión y que no recibieron tratamiento adyuvante (HR, 0.23; IC 95%, 0.13-0.40; p < 0.001).

LIMITACIONES

Diseño retrospectivo. CONCLUSIÓN:: Nuestros resultados confirman el valor pronóstico de la invasión perineural en el cáncer de colon estadios I-II y III. Sin embargo, los pacientes con enfermedad ganglionar negativa e invasión perineural no se beneficiaron significativamente de la terapia adyuvante. Se requiere más información sobre el tratamiento postoperatorio en el cáncer de colon positivo para la invasión perineural con ganglios negativos. Vea el Resumen del video en http://links.lww.com/DCR/A988.

Accelerated perineural invasion in colitis-associated cancer: A retrospective cohort study

Perineural invasion (PNI) is a prognostic factor in patients with colorectal cancer. Neurotrophic factors, molecular determinants of PNI, are altered in their expression levels in patients with ulcerative colitis. In this study, we evaluated the frequency of PNI in colitis-associated cancer (CAC) and sporadic cancer.We retrospectively reviewed 778 colorectal cancers with pathological T3-T4 in 761 patients all of whom were surgically resected without preoperative treatment. The lesions were classified into either CAC or sporadic cancer based on the clinical information. Clinicopathological findings including PNI were compared between CACs and sporadic cancers. Moreover, we analyzed the risk factors for positive PNI by multivariate analysis using a logistic regression model.Ten of the cancers (1.3%) were diagnosed as CACs, and the remaining 768 as sporadic cancers. CACs were characterized by being nonobstructive and predominantly located in the rectum. The CACs had a larger size and more frequent undifferentiated histology than sporadic cancers. PNI was observed more frequently in CACs (90%) than in sporadic cancers without obstruction (45%, P = .007). On multivariate analysis, CAC was one of the significant factors associated with PNI (odds ratio: 9.05, P = .040).Our results suggest that CAC was more likely to exhibit PNI than sporadic colorectal cancer.

Obstruction is associated with perineural invasion in T3/T4 colon cancer

AIM

Perineural invasion (PNI) is a risk factor for recurrence and metastasis and consequently leads to decreased survival in patients with various malignancies. Recent studies showed that stent placement in obstructive colon cancer increases the frequency of PNI. We hypothesized that mechanical stress including obstruction itself may be associated with PNI.

METHOD

We retrospectively reviewed 496 patients with pathological T3 or T4 colon cancer who did not receive preoperative treatment. Data were collected from medical charts and pathological findings. The relationships between PNI and other clinicopathological factors were analysed using univariate and multivariate analyses.

RESULTS

PNI was observed in 239 (48%) patients. Obstruction was markedly more frequent in PNI-positive cancer (39%) than in PNI-negative cancer (24%, P = 0.0003). Multivariate analyses identified obstruction as one of the significant factors associated with PNI (OR 1.68, P = 0.028). Moreover, in 414 patients without distant metastasis who underwent complete resection, PNI was an independent factor associated with poor recurrence-free survival (hazard ratio 2.35, P = 0.003). The coexistence of PNI and obstruction resulted in greater decreases in recurrence-free survival than PNI-negative and/or non-obstructive cases.

CONCLUSION

Our results suggest that obstruction is associated with PNI and consequently contributes to an increased postoperative recurrence in colon cancer.

Prognostic significance of perineural invasion in vulvar squamous cell carcinoma

Background: Perineural invasion (PNI) is closely associated with poor survival in several types of malignant tumours, but whether this is true in vulvar squamous cell carcinoma (VSCC) is unclear. The aims of this study were to determine the prognostic significance of PNI in patients with VSCC. Patients and methods: We retrospectively analysed clinico-pathological data on 105 patients with VSCC (stages IB-IV) treated surgically at our medical center between 2005 and 2015. Results: PNI was detected in 30 (28.6%) patients, and it was significantly associated with well-known clinical risk factors: large tumour size, depth of invasion, lymphatic vascular space invasion (LVSI), and intra- or extra-nodal spread. Significantly greater proportions of patients with PNI received adjuvant therapy after surgery (P=0.001) or showed local recurrence (P=0.002). Multivariable analysis indicated that risk factors for disease-free survival were tumour size (HR 3.02, 95%CI 1.75-7.75), LVSI (HR 4.82, 95%CI 1.36-17.07), depth of invasion (HR 3.11, 95%CI 1.50-6.44), lymph node metastasis (HR 3.15, 95%CI 1.14-8.96) and positive or close surgical margins (HR 4.86, 95%CI 1.67-14.19). The latter three variables were also risk factors for overall survival. PNI was associated with significantly shorter disease-free survival (DFS) (P=0.020) and overall survival (OS) (P=0.017) based on the log-rank test. Among patients who received adjuvant treatment, Kaplan-Meier curves indicated no significant differences between PNI-positive or -negative subgroups in disease-free survival (P=0.085) or overall survival (P=0.061). Based on multivariable analysis of all patients, PNI was not a significant risk factor for either type of survival . Conclusion: PNI in VSCC is associated with significantly shorter disease-free and overall survival, though it appears to be a weak independent predictor of worse prognosis. Combining PNI with other risk factors may be useful for predicting whether postoperative adjuvant therapy will be needed.

Colon Adenocarcinoma Stage IIA-Can We Predict Relapse?

PURPOSE

To determine prognostic factors for stage IIA colon cancer (CC) recurrence in patients undergoing curative intent surgery without adjuvant treatment.

METHODS

Single-centre cohort study. All patients with stage IIA CC discussed in a multidisciplinary colorectal cancer clinic from January 2010 to December 2012 were evaluated. Clinical data, laboratory data and tumour features, including expression of DNA repair proteins (EDRP), were analysed. Assessment of overall and disease free survival, recurrence, recurrence site and recurrence's method of diagnosis was performed. The associations between variables were tested through the Fisher's exact test (SPSS 23).

RESULTS

Fifty-five patients were included (55% male gender; mean age at diagnosis was 70.3 years (42-88)). CC was in the left colon in 62%, high grade in 7% and had lymphovascular invasion in 7% of the cases. Only one patient was submitted to emergent surgery for obstructive symptoms. In 55% of cases ≥ 12 lymph nodes were collected. There was EDRP loss in nine patients (MLH1/PMS2: six; MSH2/MSH6: three)-only two fulfilled revised Bethesda criteria. Recurrence occurred in five patients (8.9%), and it was diagnosed through surveillance in all of them. No variable showed a statistically significant association with recurrence; however, there were no recurrences in patients with EPRD loss (p = 0.209). Mean follow-up time was 43 months (2-70). In those with recurrence, mean disease-free survival was 23.4 months.

CONCLUSIONS

The overall good prognosis and absence of recurrence predictive factors were confirmed, validating the decision of not to submit stage IIA CC patients to chemotherapy risks.

Development and Validation of a Nomogram for Preoperative Prediction of Perineural Invasion in Colorectal Cancer

Background

In colorectal cancer (CRC), perineural invasion (PNI) is usually identified histologically in biopsy or resection specimens and is considered a high-risk feature for recurrence of CRC and is an indicator for adjuvant therapy. Preoperative identification of PNI could help determine the need for adjuvant therapy and the approach to surgical resection. This study aimed to develop and validate a nomogram for the preoperative prediction of PNI in patients with CRC.

Material/Methods

A total of 664 patients with CRC from a single center were classified into a training dataset (n=468) and a validation dataset (n=196). The least absolute shrinkage and selection operator (LASSO) regression model was used to select potentially relevant features. Multivariate logistic regression analysis was used to develop the nomogram. The performance of the nomogram was assessed based on its calibration, discrimination, and clinical utility.

Results

The nomogram consisted of five clinical features and provided good calibration and discrimination in the training dataset, with an area under the curve (AUC) of 0.704 (95% CI, 0.657–0.751). Application of the nomogram in the validation cohort showed acceptable discrimination, with the AUC of 0.692 (95% CI, 0.617–0.766) and good calibration. Decision curve analysis (DCA) showed that the nomogram was clinically useful.

Conclusions

The nomogram developed in this study might allow clinicians to predict the risk of PNI in patients with CRC preoperatively. The nomogram showed favorable discrimination and calibration values, which may help optimize preoperative treatment decision-making for patients with CRC.

Lymphovascular Invasion and Perineural Invasion Negatively Impact Overall Survival for Stage II Adenocarcinoma of the Colon

BACKGROUND

Lymphovascular invasion and perineural invasion are histopathological features associated with higher-risk colon cancer.

OBJECTIVE

The purpose of this study was to quantify the impact of lymphovascular and perineural invasion on overall survival after diagnosis and to determine the protective effect of adjuvant chemotherapy for early adenocarcinoma with high-risk factors.

DESIGN

This was a retrospective database review of the 2010-2014 National Cancer Database for colon cancer.

SETTINGS

Individuals diagnosed with invasive adenocarcinoma of the colon (histology code 8140) with primary surgical resection with >12 nodes harvested and no positive nodes on pathological examination were included.

PATIENTS

A total of 32,493 patients underwent surgical resection for stage II adenocarcinoma of the colon.

INTERVENTIONS

The study involved multivariate Cox regression analysis of the impact of lymphovascular and perineural invasion and adjuvant chemotherapy on overall survival after a diagnosis of stage II adenocarcinoma of the colon.

MAIN OUTCOME MEASURES

Survival after a diagnosis of stage II adenocarcinoma of the colon was measured.

RESULTS

Five-year survival after diagnosis and surgical resection without adjuvant chemotherapy was lower for patients with lymphovascular (60.0%), perineural (56.9%), and lymphovascular and perineural invasion (55.8%) compared with double-negative disease (66.1%). Log-rank testing confirmed that adjuvant chemotherapy improved 5-year survival after diagnosis for lymphovascular (85.5%), perineural (83.6%), and lymphovascular and perineural invasion (74.3%). After controlling for differences in cohorts, Cox regression analysis showed an increased HR for mortality of 14.0% for lymphovascular (HR = 1.141 (95% CI, 1.060-1.228)), 32.1% for perineural (HR = 1.321 (95% CI, 1.176-1.483)), and 41.0% for lymphovascular and perineural invasion (HR = 1.409 (95% CI, 1.231-1.612)) compared with having neither. Chemotherapy showed a 43% reduction in hazard for mortality (HR = 0.570 (95% CI, 0.513-0.633)).

LIMITATIONS

The study was limited by its retrospective review and observational bias.

CONCLUSIONS

Lymphovascular and perineural invasion have a detrimental effect on survival after diagnosis of stage II adenocarcinoma of the colon. Chemotherapy may be protective specifically when lymphovascular and perineural invasion are present. See Video Abstract at http://links.lww.com/DCR/A786.

A Review of Current Challenges in Colorectal Cancer Reporting

Context.—

Pathologic assessment of colorectal cancer resection specimens plays an important role in postsurgical management and prognostication in patients with colorectal cancer. Challenges exist in the evaluation and reporting of these specimens, either because of difficulties in applying existing guidelines or related to newer concepts.

Objective.—

To address challenging areas in colorectal cancer pathology and to provide an overview of the literature, current guidelines, and expert recommendations for the handling of colorectal cancer resection specimens in everyday practice.

Data Sources.—

PubMed (US National Library of Medicine, Bethesda, Maryland) literature review; reporting protocols of the College of American Pathologists, the Royal College of Pathologists of the United Kingdom, and the Japanese Society for Cancer of the Colon and Rectum; and classification manuals of the American Joint Committee on Cancer and the Union for International Cancer Control.

Conclusions.—

This review has addressed issues and challenges affecting quality of colorectal cancer pathology reporting. High-quality pathology reporting is essential for prognostication and management of patients with colorectal cancer.

A novel histologic grading system based on lymphovascular invasion, perineural invasion, and tumor budding in colorectal cancer

PURPOSE

This study aimed to evaluate the prognostic significance of lymphovascular (LVI), perineural invasion (PNI), and tumor budding positivity in patients with colorectal cancer.

METHODS

From January 2008 to December 2011, 3707 consecutive patients who underwent curative surgery for stage I-III colorectal cancer were assessed. These patients were then categorized into four groups based on LVI, PNI, and tumor budding (risk grouping): all negative (n = 1495), 1 + only (n = 1063), 2 + only (n = 861), and all positive (n = 288).

RESULTS

With a median follow-up period of 52 months, the 5-year disease-free survival rates of the risk groups were significantly different in terms of cancer staging (stage I, Stage II, and Stage III: P = 0.006, P < 0.001, and P < 0.001, respectively). In the multivariate analysis, risk grouping was an independent prognostic factor of disease-free survival. Preoperative carcinoembryonic antigen level, tumor size, T category, and N category were independent predictors of LVI, PNI, and tumor budding positivity.

CONCLUSION

Risk grouping based on LVI, PNI, and tumor budding positivity is a strong predictor of disease-free survival in patients with colorectal cancer.

Neutrophils to lymphocytes ratio as a useful prognosticator for stage II colorectal cancer patients

Background

The incidence of colorectal cancer (CRC) is expected to increase by 80% in year 2035. Even though advantages in treatment of CRC have being made over the last decades, the outcome remains poor. Recently, several inflammatory markers including pretreatment neutrophil to lymphocyte ratio (NLR), have being used as prognostic factors, since host inflammatory response to cancer is believed to determine disease progression.

The aim of this study is to evaluate the prognostic significance of pretreatment NLR, in terms of overall survival (OS), 5-year survival, disease-free survival (DFS) and recurrence, in CRC patients who underwent curative resection.

Methods

We retrospectively reviewed 296 patients, who were submitted to elective surgery as first therapeutic option in curative intent, between January 2010 and December 2015. Pretreatment NLR, as well as demographics, clinical, histopathologic, and laboratory data were analyzed. Univariate and multivariate analyses were conducted to identify prognostic factors associated with OS, 5-year survival, DFS and recurrence.

Results

The cutoff point of NLR was calculated with Kaplan-Meier curves and log-rank test to 4.7. Univariate and multivariate analyses disclosed elevated NLR as a significant dismal prognostic factor for DFS (HR 1.88; 95% CI 1.01–3.52; p = 0.048), 5-year survival (HR 2.14; 95% CI 1.12–4.10; p = 0.021) and OS (HR 2.11; 95% CI 1.11–4.03; p = 0.023). In a subgroup analysis, in patients with stage II CRC, NLR > 4.7 was a stronger poor predictor for DFS (HR 2.76; 95% CI 1.07–7.13; p = 0.036), 5-year survival (HR 3.84; 95% CI 1.39–10.63; p = 0.01) and OS (HR 3.62; 95% CI 1.33–4.82; p = 0.012). After adjusting stage for gender, age, location of the primary tumor, differentiation, as well as the presence of perineural, vascular, and lymphovascular invasion, the significance of NLR > 4.7 became more prominent for DFS (HR 2.85; 95% CI 1.21–6.73; p = 0.0176), 5-year survival (HR 4.06; 95% CI 1.66–9.93; p = 0.002) and OS (HR 4.07; 95% CI 1.69–9.91; p = 0.002) in stage II patients.

Conclusion

Pretreatment NLR > 4.7 is a poor prognostic factor for DFS, 5-year survival and OS in CRC patients undergoing curative resection. The dismal prognostic effect of NRL is magnified in Stage II CRC patients.

A Transverse Colectomy is as Safe as an Extended Right or Left Colectomy for Mid-Transverse Colon Cancer

BACKGROUND

Although extended colectomy is often chosen for patients with transverse colon cancer, the optimal surgical approach for mid-transverse colon cancer has not been established.

METHODS

We identified patients who underwent a transverse (TC) or an extended colectomy (EC) for mid-transverse colon cancer between 2004 and 2014. To adjust for potential selection bias between the groups, a propensity score matching analysis was performed.

RESULTS

A total of 103 patients were included, of whom 63% underwent EC (right 47%, left 17%) and 37% TC. EC patients tend to have worse short-term outcomes. Although fewer lymph nodes were harvested after TC, 5-year overall (OS) ad disease-free survival (DFS) was comparable between the groups. When comparing long-term outcomes stage-by-stage, worse OS and DFS were seen in stage-II. All stage-II patients died of a non-cancer-related cause and recurrence occurred in pT4 TC patients who did not receive adjuvant therapy. The propensity-matched cohort demonstrated similar postoperative morbidity, but more laparoscopic procedures in EC. Additionally, TC tumors were correlated with poorer histopathological features and disease recurrence was only seen after TC.

CONCLUSION

Our study underlines the oncological safety of a transverse colectomy for mid-transverse colon cancer. Although TC tumors were associated with poorer histopathological features, survival rates were comparable.

Early PET-CT in patients with pathological stage III colon cancer may improve their outcome: Results from a large retrospective study

Background

Current staging of pathological stage III colon cancer (CC) is suboptimal; many patients recur despite unremarkable preoperative staging. We previously reported that early postoperative PET‐CT can alter the stage and management of up to 15% of patients with high‐risk stage III CC. This study aimed to determine the role of the test in the general stage III CC population.

Methods

A retrospective study of all consecutive patients with stage III CC who underwent early postoperative PET‐CT between 2005 and 2017.

Results

A total of 342 patients, 166 (48.5%) males, median age 66 years (range, 29‐90), were included. Pathological stage was IIIA, IIIB, and IIIC in 18 (5.3%), 257 (75.1%), and 67 (19.6%) patients, respectively. Median number of positive lymph nodes was 2 (range, 0‐32). PET‐CT results modified the management of 46 patients (13.4%): 37 (10.8%) with overt metastatic disease and 9 (2.6%) with a second primary. The 5‐year disease‐free survival for true stage III patients was 81%. The median overall survival for the entire cohort and for true stage III patients was not reached and was 57.2 months for true stage IV. Of the 37 patients found to be metastatic, 14 (37.8%) underwent curative treatments and 9/14 (64.3%) remain disease‐free, with a median follow‐up of 83.8 months. Predictive factors for upstaging following PET‐CT were identified.

Conclusion

Early postoperative PET‐CT changed the staging and treatment of 13.4% of stage III CC patients and has the potential for early detection of curable metastatic disease. Outcome results are encouraging. Prospective validation is ongoing.

Opposite functions of GSN and OAS2 on colorectal cancer metastasis, mediating perineural and lymphovascular invasion, respectively

The present study aimed to identify molecules associated with lymphovascular invasion (LVI) and perineural invasion (PNI) and to examine their biological behavior in colorectal cancer (CRC). LVI- and PNI-associated molecules were identified and verified using sequential processes including (1) identification of 117 recurrence-associated genes differentially expressed on RNA-seq analysis using primary cancer tissues from 130 CRC patients with and without systemic recurrence; (2) analysis of molecules associated with LVI and PNI; (3) assessment of biological properties by measuring proliferation, anoikis, invasion/migration, epithelial-mesenchymal transition and autophagy flux; and (4) verification of disease-free survival using public datasets. Gelsolin (GSN) and 2'-5'-oligoadenylate synthetase 2 (OAS2) were associated with PNI and LVI, respectively. Invasion potential was >2-fold greater in GSN-overexpressing LoVo cells than in control cells (p<0.001–0.005), whereas OAS2-overexpressing RKO cells showed reduced invasion (p<0.001–0.005). GSN downregulated E-cadherin, β-catenin, claudin-1 and snail, and upregulated N-cadherin and ZEB1, whereas OAS2 overexpression had the opposite effects. Several autophagy-related proteins including ATG5-12, ATG6/BECN1, ATG7 and ATG101 were downregulated in GSN-overexpressing LoVo cells, whereas the opposite pattern was observed in OAS2-overexpressing RKO cells. Patients with low GSN expression had significantly higher 5-year recurrence-free survival (RFS) rates than those with GSN overexpression (73.6% vs. 64.7%, p = 0.038), whereas RFS was longer in patients with OAS2 overexpression than in those with underexpression (73.4% vs. 63.7%, p = 0.01). In conclusion, GSN and OAS2 were positively and negatively associated with recurrence, respectively, suggesting their potential value as predictors of recurrence or therapeutic targets in CRC patients.

Histogram Analysis of Perfusion Parameters from Dynamic Contrast-Enhanced MR Imaging with Tumor Characteristics and Therapeutic Response in Locally Advanced Rectal Cancer

Purpose

To explore the role of histogram analysis of perfusion parameters from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on entire tumor volume in discriminating tumor characteristics and predicting therapeutic response in rectal cancer.

Materials and Methods

Thirty-seven DCE-MRIs of locally advanced rectal cancer patients who received chemoradiation therapy (CRT) before surgery were analyzed by pharmacokinetic model for quantification and histogram analysis of perfusion parameters. The results were correlated with tumor characteristics including EGFR expression, KRAS mutation, and CRT response based on the pathologic tumor regression grade (TRG).

Results

The area under the contrast agent concentration-time curve (AUC) skewness was significantly lower in patients with node metastasis. The v_p histogram parameters were significantly higher in group with perineural invasion (PNI). The receiver operating characteristics (ROC) curve analyses showed that mode v_p revealed the best diagnostic performance of PNI. The values of K^trans and k_ep were significantly higher in the group with KRAS mutation. ROC curve analyses showed that mean and mode K^trans demonstrated excellent diagnostic performance of KRAS mutation. DCE-MRI parameters did not demonstrate statistical significance in correlating with TRG.

Conclusion

These preliminary results suggest that a larger proportion of higher AUC skewness was present in LN metastasis group and a higher v_p histogram value was present in rectal cancer with PNI. In addition, K^trans and k_ep histogram parameters showed difference according to the KRAS mutation, demonstrating the utility of the histogram of perfusion parameters derived from DCE-MRI as potential imaging biomarkers of tumor characteristics and genetic features.

Newly recognized extratumoral features of colorectal cancer challenge the current tumor-node-metastasis staging system

One of the most common malignant tumors in humans, colorectal cancer has been extensively studied during the past few decades. Staging colorectal cancer allows clinicians to obtain precise prognostic information and apply specific treatment procedures. Apart from remote metastases, the depth of tumor infiltration and lymph node involvement have traditionally been recognized as the most important factors predicting outcome. Variations in the molecular signature of colorectal cancer have also revealed differences in phenotypic aggressiveness and therapeutic response rates. This article presents a review of the extratumoral environment in colorectal surgery.

Session 1: Colon cancer - 10 years behind the rectum

The improvements in surgical technique brought about by the widespread adoption of total mesorectal excision plane dissection in rectal cancer has substantially improved survival and recurrence rates from this disease. For the first time in 50 years, the outcomes in rectal cancer have overtaken those of colon cancer. Professor Madoff's overview lecture and the experts' round table discussion address whether applying the surgical principles already achieved in rectal cancer can meet with similar success in colon cancer, how this can be achieved and the challenges we face.

Rectal cancer and the pathologist

Examination of the rectum by pathologists is instrumental in the management of patients affected by rectal carcinoma. That role includes evaluation of multiple gross and microscopic features that convey prognostic implications. The analysis is based on the authors' experience handling rectal specimens along with review of the pertinent literature in these areas: margins of excision, quality of the mesorectum, diligence and techniques to sample lymph nodes, tumor budding, grading of residual amount of carcinoma after preoperative therapy, vascular/perineural invasion, and staging the tumor. Pathologists must communicate the findings in a clear manner. Evaluation of margins and completeness of mesorectum are markers of the quality of surgical excision. The number of lymph nodes obtained and examined is dependent in great part on the diligence of the pathologist finding them in the mesenteric adipose tissue. There are grades for budding and response to prior chemoradiation therapy. The location of vascular invasion (extramural vs. intramural) may predict aggressive behavior. Pathologists proactively are to choose sections of tumor for molecular testing. Meticulous macro- and microscopic evaluation of specimens for rectal carcinoma by pathologist is needed to determine an accurate assessment of staging and other prognostic factors. The modern pathologists play a pivotal part in the care and management of patients suffering from rectal adenocarcinoma. That role goes from the initial histological diagnosis to the gross and microscopic examination of the excised specimens. Based on that examination pathologists issue statements that not only evaluate the quality of the surgical procedure, but also through the application of molecular tests they give light on prognostic factors and information for therapeutic purposes.

Assessment of risk factors affecting mortality in patients with colorectal cancer

INTRODUCTION

The most important risk factors for colorectal cancer are age, high ASA score, anemia, low albumin, tumor stage, histopathological properties, tumor's relationship with adjacent tissues, positivity of surgical borders and timing of the surgical procedure.

AIM

To determine possible risk factors for mortality in patients undergoing colorectal cancer surgery.

MATERIAL AND METHODS

The medical records of 101 consecutive patients who underwent colorectal cancer surgery at the Department of Surgery, Sutcu Imam University Faculty of Medicine, Kahramanmaras, Turkey between January 2008 and November 2015 were retrospectively reviewed. The patients were divided into two groups: surviving (n = 76) and deceased (n = 25) groups. The groups were compared in terms of several demographic, clinical, biochemical, and histopathological parameters. In addition, risk factors for mortality were analyzed with multivariate analysis. SPSS 22.2, PAST 3, and MedCalc 14 software packages were used for statistical analyses.

RESULTS

The surviving and deceased groups significantly differed with respect to age (p = 0.001), hemoglobin (p = 0.001), lymph node positivity (p = 0.009), positive lymph node/total lymph node ratio (p = 0.012), thrombocyte count (p = 0.047), lymphovascular invasion (p = 0.028), urgency of admission (emergency/elective) (p = 0.036), and postoperative carcinoembryonic antigen (CEA) level (p = 0.002). A receiver operating characteristics curve was drawn to determine the cut-off values of various parameters including age (63), hemoglobin (12.8), node positivity (3), positive/total lymph node ratio (0.435) and thrombocyte count (308), with age (p < 0.001), hemoglobin (p < 0.001), node positivity (p = 0.025) and positive/total lymph node ratio (p = 0.024) being significantly different. A multivariate analysis revealed that age (p = 0.049), hemoglobin (p = 0.045), and positive/total lymph node ratio (p = 0.025) were independent risk factors for mortality.

CONCLUSIONS

This study shows that older age, lower hemoglobin level, and high positive/total lymph node ratio were independent risk factors for mortality among colorectal cancer patients.

Are pathological high-risk features in locally advanced rectal cancer a useful selection tool for adjuvant chemotherapy?

BACKGROUND

Several histological high-risk factors are used as an indication for adjuvant therapy in stage II colon cancer. Those and other factors, including lymphatic invasion, perineural invasion (PNI), venous invasion and tumour budding are associated with decreased outcome. In this study, we evaluated the prognostic and predictive values of these biomarkers in a cohort of rectal cancer patients.

MATERIALS AND METHODS

The trial-based cohort consisted of 221npTNM stage II-III rectal cancer patients, included in the PROCTOR/SCRIPT trial, a multicentre randomised phase III trial. Patients treated with neoadjuvant radiotherapy and TME surgery were randomised between adjuvant chemotherapy or observation. Lymphatic invasion, PNI, extramural venous invasion, intramural venous invasion and tumour budding were determined in standard tissue slides.

RESULTS

The presence of PNI (HR 3.36; 95% CI 1.82-6.21), extramural vascular invasion (HR 1.93; 95% CI 1.17-3.19) and tumour budding (HR 1.83, 95% CI 1.11-3.03) was associated with a significant worse overall survival. The presence of ≥2 adverse biomarkers resulted in a stronger prediction of adverse outcome in terms of overall survival (HR 2.82; 95% CI 1.66-4.79), disease-free survival (HR 2.27; 95% CI 1.47-3.48), and distant recurrence (HR 2.51; 95% CI 1.56-4.02). None of these markers alone or combined predicted a beneficial effect of adjuvant chemotherapy.

DISCUSSION

We confirmed that several stage-independent biomarkers were significantly associated with a decreased outcome in rectal cancer patients. More importantly, these markers did not have predictive value and are thus not useful to select for adjuvant therapy in rectal cancer.

Microscopic biliary and perineural invasion and clinical outcome after neoadjuvant bevacizumab-based chemotherapy and liver resection in patients with colorectal liver metastases

BACKGROUND

The value of microscopic biliary and perineural invasion as prognostic biomarkers in patients with resectable colorectal liver metastases (CLM) who undergo neoadjuvant chemotherapy and liver resection is still unclear. This retrospective study was performed to elucidate this issue.

METHODS

Histologic slides of resected CLM of patients who underwent neoadjuvant bevacizumab-based chemotherapy and liver resection were investigated with respect to biliary and perineural invasion. Presence of invasion was correlated with radiologic and histologic response, recurrence-free survival (RFS) and overall survival (OS).

RESULTS

One hundred forty-one patients were enrolled. There was a significant association between biliary and perineural invasion, respectively (P = 0.001). Moreover, both biliary and perineural invasion were associated with bilobar metastatic spread and higher number of metastases, while perineural invasion was also associated with a higher Fong score. No significant association was found with response. In univariable analysis, biliary and perineural invasion were associated with shorter RFS (median 10.1 vs. 13.5 months, HR 2.09, P = 0.010 and 7.6 vs. 14.0, HR 2.23, P = 0.001, respectively). Biliary invasion was also associated with shorter OS (median 32.8 months vs. not reached, HR 2.78, P = 0.010), however these results did not remain significant in multivariable analysis.

CONCLUSIONS

In patients with resectable colorectal liver metastases undergoing neoadjuvant bevacizumab-based chemotherapy and liver resection, biliary and perineural invasion are associated with higher tumor load but may not be prognostic biomarkers.

Impact of endoscopic stent insertion on detection of viable circulating tumor cells from obstructive colorectal cancer

The placement of a self-expanding metallic stent (SEMS) in obstructive colorectal cancer (OCRC) is acknowledged to be a safe and effective procedure for the relief of obstruction. However, there is concern that shear forces acting on the tumor during stent expansion may release cancer cells into the circulation, resulting in a poor prognosis. The aim of the present study was to determine whether colonic stent insertion increases viable circulating tumor cells (v-CTCs). A telomerase-specific replication-selective adenovirus-expressing GFP (TelomeScanF35) detection system was used to detect v-CTCs in 8 OCRC patients with a SEMS before and after stent insertion and after surgical resection. In 7 patients, a SEMS was inserted as a bridge to surgery (BTS), and in one patient, a SEMS was inserted for palliation. Surgical resection (R0) was performed in 7 patients. Four patients had no v-CTCs before SEMS placement, two of four measurable patients had an increased number of v-CTCs after SEMS placement (1-3 v-CTCs), and one of two patients with increased v-CTCs developed distant lymphatic metastasis despite curative resection. Four patients had v-CTCs (1-19 cells) before SEMS placement, and two of these four patients had an increase in the number of v-CTCs (20-21 cells) after SEMS placement, while one of the four patients died early with distant metastasis. The present study demonstrated that endoscopic stent insertion for OCRC may result in tumor cell dissemination into the peripheral circulation and may induce distant metastases.

The role of enteric neurons in the development and progression of colorectal cancer

The enteric nervous system (ENS) is the intrinsic neural network of the gastrointestinal tract, which is essential for regulating gut functions and intestinal homeostasis. The importance of the ENS is underscored by the existence of severe gastrointestinal diseases, such as Hirschsprung's disease and intestinal pseudo-obstruction, which arise when the ENS fails to develop normally or becomes dysregulated. Moreover, it is known that enteric neurons are involved in intestinal inflammation. However, the role of the ENS in colorectal cancer (CRC) carcinogenesis remains poorly understood, even though processes like perineural invasion and neoneurogenesis are important factors in CRC. Here we summarize how enteric neurons are affected during CRC and discuss the influence of enteric neurons, either direct or indirect, on the development and/or progression of CRC. Finally, we illustrate how the ENS could be targeted as a potential anti-cancer therapy, establishing the ENS as an integral part of the tumor microenvironment.

Efficacy and safety of taxane-based systemic chemotherapy of advanced gastric cancer: A systematic review and meta-analysis

Taxanes are chemotherapeutic agents commonly used to treat several cancers. However, the effects of taxanes on advanced gastric cancer (AGC) are still not clear, especially when used as a first-line treatment. This systematic review and meta-analysis aims to investigate the efficacy and safety of taxanes as a first-line treatment of AGC. The quality of our included studies was assessed using the Cochrane risk of bias tool for RCTs and NOS scale for nRCTs, and the data of the included studies was of satisfactory quality to analyze. The outcomes included overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and toxicity. Taxanes significantly improved OS (HR = 0.84, 95% CI 0.76-0.92, P = 0.0004) and had a slight effect on ORR (RR = 1.23, 95% CI 1.00-1.51, P = 0.05). However, taxanes may also increase the risks of neutropenia and leucopenia, similar to effects observed in other conventional chemotherapeutic treatments such as oxaliplatin and epirubicin. Therefore, patient characteristics including concomitant diseases, physical condition, and prior therapies should be considered before selecting taxane-based treatments for AGC.

Extranodal extension status is a powerful prognostic factor in stage III colorectal cancer

Purpose

The present study aimed to evaluate the clinicopathologic characteristics of patients with extranodal extension (ENE) and the prognostic implications of ENE in stage III colorectal cancer (CRC).

Results

ENE was more frequent in younger patients and those with rectal cancer, higher T stage, higher N stage, lymphovascular invasion (LVI), and perineural invasion (PNI). Five-year disease-free survival (DFS) and overall survival (OS) were lower in patients with ENE-positive than in those with ENE-negative tumors (DFS, 66.4% vs. 80.1%; and OS, 74.8% vs. 85.6%, respectively; P < 0.001 both). In multivariate analysis, pathologic stage, the presence of ENE, LVI, PNI, and no adjuvant chemotherapy were significant independent prognostic factors for DFS and OS. There were no statistically significant differences in DFS and OS between ENE-positive stage IIIB tumors and ENE-negative stage IIIC tumors.

Materials and Methods

The records of 1,948 stage III CRC patients who underwent curative surgery between January 2003 and December 2010 were retrospectively reviewed.

Conclusions

The presence of ENE is independently and significantly associated with lower DFS and OS rates after curative resection for stage III CRC. ENE status should be considered in both the pathologic report and CRC staging system.

Prognosis and Progression of ESCC Patients with Perineural Invasion

Perineural invasion (PNI) has been recognized as a poor prognostic factor in several malignancies, but the definition and pathogenesis of PNI in esophageal squamous cell carcinoma (ESCC) remains to be defined. PNI was evaluated by H&E staining and S100 immunohistochemistry. The predictive value of PNI in the prognosis of ESCC patients was analyzed. PNI was evaluated in vitro and in vivo. A total of 54 specimens (17.88%) were defined as PNI-a and 99 specimens (32.78%) as PNI-b. S100 staining was superior to H&E staining for PNI detection (50.66% vs 27.15%, P < 0.001, κ = 0.506). Tumor depth (P = 0.001), tumor stage (P = 0.010), and vascular invasion (P < 0.001) were significantly associated with PNI. PIN-a and PNI-b had significant lower disease free survival (DFS) and disease specific survival (DSS) than PNI-0 patients, and the prognosis of PNI-b patients was significantly worse than PNI-a patients for DFS (P = 0.009). PNI was an independent predictor for DFS and DSS in ESCC as evaluated by univariate and multivariate analyses. ESCC cells could metastasize along the nerve in vitro and in vivo, and PNI was a dynamic process. S100 staining significantly improved the accuracy of PNI detection. PNI was associated with local recurrence and poor prognosis of ESCC patients.

Prognostic and Oncologic Significance of Perineural Invasion in Sporadic Colorectal Cancer

BACKGROUND

The presence of perineural invasion (PNI) in colorectal cancer (CRC) indicates a more aggressive phenotype, resulting in a poor prognosis. The aims of this study were to evaluate the oncologic outcome of PNI+ tumors and to investigate whether PNI status affects patient survival.

METHODS

The study retrospectively enrolled 3807 patients from a single institution who underwent surgery for colorectal adenocarcinoma between January 2006 and December 2010. The patients were classified into two groups based on PNI status: PNI+ and PNI-.

RESULTS

The PNI+ group included 565 patients (14.8 %) and had significantly more involved circumferential resection margins (p = 0.001) and a more advanced TNM stage (p = 0.001) than the PNI- group. Compared with the PNI- group, the PNI+ group had worse 5-year overall survival (65 vs. 88 %; p = 0.001) and 5-year disease-free survival (63 vs. 85 %; p = 0.001). Among PNI+ patients with stage IIA disease, those who received adjuvant therapy had significantly greater 5-year overall survival than those who did not (89.3 vs. 50.8 %; p = 0.001). In multivariate analyses, PNI+ was an independent negative prognostic factor for 5-year overall survival (hazard ratio [HR] 1.518, 95 % confidence interval [CI] 1.175-1.961; p = 0.001) and 5-year disease-free survival (HR 1.495, 95 % CI 1.237-1.806; p = 0.001).

CONCLUSIONS

PNI positivity is an independent predictor of aggressive behavior and unfavorable prognosis in CRC. Further evaluation is needed to confirm the impact of PNI status on survival in stage IIA CRC.

Large-Scale Analysis of Gene Expression Data Reveals a Novel Gene Expression Signature Associated with Colorectal Cancer Distant Recurrence

Colorectal cancer (CRC) is the fourth-ranked cause of cancer-related deaths worldwide. Despite recent advances in CRC management, distant recurrence (DR) remains the major cause of mortality in patients with preoperative chemotherapy and radiotherapy, underscoring a need to precisely identify novel gene signatures for predicting the risk of systemic relapse. Herein, we integrated two independent CRC gene expression datasets: the GSE71222 dataset, including 26 patients who developed DR and 126 patients who did not develop DR, and the GSE21510 dataset, including 23 patients who developed DR and 76 patients who did not develop DR. Our data revealed 37 common upregulated genes (fold change (FC) ≥ 1.5, P < 0.05) and three common downregulated genes (FC ≤ 1.5, P < 0.05) between DR and non-recurrent patients from the two datasets. We subsequently validated the upregulated gene panel in the Cancer Genome Atlas CRC datasets (379 patients), which identified a five-gene signature (S100A2, VIP, HOXC6, DACT1, KIF26B) associated with poor overall survival (OS, log-rank test P-value: 1.19 × 10⁻⁴) and poor disease-free survival (DFS, log-rank test P-value: 0.002). In a Cox proportional hazards multiple regression model, the five-gene signature and tumor stage retained their significance as independent prognostic factors for CRC DFS and OS. Therefore, our data identified a novel DR gene expression signature associated with worse prognosis in CRC.

Total mesorectal excision for cancer: histological and immunohistochemical evidence of nerve removal and risk-factor analysis

AIM

Whether or not nerve-sparing rectal-cancer surgery can effectively prevent removal of the pelvic autonomic nerves has not been substantiated microscopically. We aimed to analyse the quality of nerve preservation in female patients by quantifying residual nerve fibres in total mesorectal excision specimens, to analyse pro-erectile function of the nerve fibres removed and to determine risk factors for pelvic denervation.

METHOD

Serial transverse sections from female patients, 64 ± 18 years of age, were studied after the mesorectal fascia was inked and studied histologically [using anti-S100 and anti-neuronal nitric oxide synthase (nNOS) antibodies]. Nerve fibres located within 1 mm of the inked surface were counted and analysed according to type of surgery, tumour location, pT stage, circumferential resection margin and the necessity for a posterior colpectomy.

RESULTS

Twelve specimens were analysed. Per specimen, the mean number of nerve-fibre sections outside the mesorectum was 5.3 ± 3.6 (range: 1-12). The mean number of fibres per specimen was 6.4 ± 4.1 in patients having a low-rectal tumour and 4.4 ± 2.9 in those with mid or higher rectal tumours (P = 0.42). The mean number of fibres was higher (9.2) for T4 tumours than for T2/T3 tumours (5.0 ± 3.5), but this difference was not statistically sigmificant (P = 0.25). Patients having abdominoperineal excision, a posterior colpectomy or a circumferential resection margin of less than 1 mm had significantly more nerve fibres in the specimen (10.6 ± 1.9 vs 4.4 ± 2.8; P = .041). Fibres localized at the anterolateral rectum corresponded to branches of the neurovascular bundle, expressing rich pro-erectile activity (positive anti-nNOS immunostaining).

CONCLUSION

The neurovascular bundle is a key risk zone for pelvic denervation during total mesorectal excision. Abdominoperineal excision, posterior colpectomy and an invaded circumferential resection margin are associated with perineal denervation.

Systematic review and meta-analysis of the impact of tumour budding in colorectal cancer

Background:

Tumour budding is a histological finding in epithelial cancers indicating an unfavourable phenotype. Previous studies have demonstrated that it is a negative prognostic indicator in colorectal cancer (CRC), and has been proposed as an additional factor to incorporate into staging protocols.

Methods:

A systematic review of papers until March 2016 published on Embase, Medline, PubMed, PubMed Central and Cochrane databases pertaining to tumour budding in CRC was performed. Study end points were the presence of lymph node metastases, recurrence (local and distal) and 5-year cancer-related death.

Results:

A total of 7821 patients from 34 papers were included, with a mean rate of tumour budding of 36.8±16.5%. Pooled analysis suggested that specimens exhibiting tumour budding were significantly associated with lymph node positivity (OR 4.94, 95% CI 3.96–6.17, P<0.00001), more likely to develop disease recurrence over the time period (OR 5.50, 95% CI 3.64–8.29, P<0.00001) and more likely to lead to cancer-related death at 5 years (OR 4.51, 95% CI 2.55–7.99, P<0.00001).

Conclusions:

Tumour budding in CRC is strongly predictive of lymph node metastases, recurrence and cancer-related death at 5 years, and its incorporation into the CRC staging algorithm will contribute to more effective risk stratification.