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]

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.

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.

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.

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.