Prognostic significance of lymphovascular invasion in sporadic colorectal cancer

Prognosticators of Long-Term Outcomes of TNM Stage II Colorectal Cancer: Molecular Patterns or Clinicopathological Features

BACKGROUND

Patients with stage II colorectal cancer (CRC) have a higher risk of recurrence when they have certain risk factors, including clinical and pathological patterns. However, as the prognostic role of molecular patterns for stage II disease is still unclear, this study aimed to investigate it.

METHODS

A total of 509 patients with stage II CRC were enrolled, and all clinical, pathological, and molecular data were collected. Molecular patterns included microsatellite instability (MSI); elevated microsatellite alterations at selected tetranucleotides (EMAST) status; and expression of RAS/RAF genes, genes of the APC pathway, and other gene mutations. The endpoints were oncological outcomes, including overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), local recurrence (LR), and distant recurrence (DR). Cox regression analysis was used.

RESULTS

Numerous molecular patterns influenced the oncological outcomes on univariate analysis, but no variable reached significance in LR. On multivariate analysis, a mucinous component (MC) > 50% (P < 0.01) was significant for OS and CSS. Lymphovascular invasion (LVI; P< 0.01), MC > 50% (P < 0.01), and EMAST-H (P = 0.02) significantly influenced DFS, whereas LVI (P < 0.01), MC > 50% (P < 0.01), and TP53 mutation (P = 0.02) were significant for DR.

CONCLUSIONS

In this study, MSI, EMAST, and RAS/RAF alterations did not influence the oncological outcomes. Overall, LVI and MC were two significant prognostic factors for DFS and DR. Thus, the histopathology, rather than the genes, plays a major role in the prognosis of patients with stage II CRC.

Prognostic Value of Lymphovascular Invasion in Patients with Stage III Colorectal Cancer: A Retrospective Study

Background

Lymph node metastasis and tumor progression depend on lymphovascular invasion (LVI). This study aimed to investigate the prognostic role of LVI in patients with stage III colorectal cancer (CRC) and to develop a prognostic nomogram.

Material/Methods

A retrospective study included 437 patients with stage III CRC. The impact of LVI on overall survival (OS) was analyzed with the Kaplan-Meier method and Cox regression model. A nomogram was constructed, and its predictive accuracy was evaluated using the concordance index (C-index) and the calibration plot.

Results

LVI was found in 19.7% of cases of stage III CRCs and was significantly correlated with high tumor grade (poor differentiation) and advanced tumor stage (all P<0.05). Patients age, a family history of cancer in a first-degree relative, pre-treatment levels of carcinoembryonic antigen (CEA), prognostic nutritional index (PNI), histological tumor grade, tumor-node-metastasis (TNM) stage, and LVI were independent prognostic indicators (all P<0.05). Compared with the LVI(−) group, patients in the LVI(+) group showed a 1.748-fold increased risk of death (P=0.004) and a significantly reduced OS rate (P<0.001). In the prognostic nomogram, the C-index was significantly increased with LVI compared with the TNM stage alone (0.742 vs. 0.593; P<0.001). Calibration plots showed good fitness of the nomogram for prediction of survival. Comparison of the nomograms with and without LVI showed that inclusion of LVI improved the C-index from 0.715 to 0.742.

Conclusions

LVI was an indicator of more aggressive biological behavior and poor prognosis in patients with stage III CRC.

Pathological risk factors and predictive endoscopic factors for lymph node metastasis of T1 colorectal cancer: a single-center study of 846 lesions

BACKGROUND

Determining the depth of invasion of early stage colorectal cancer has been emphasized as a means of improving endoscopic diagnostic accuracy. Recent studies have focused on other pathological risk factors for lymph node metastasis (LNM). We investigated the significance of depth of invasion and predictive properties of other endoscopic findings.

METHODS

We retrospectively investigated 846 patients with submucosal invasive (T1) colorectal cancer who received an accurate pathological diagnosis and were treated between January 2005 and December 2016. Pathological risk factors associated with LNM were reviewed. We divided patients into groups: low-risk T1 colorectal cancer (LRC; no risk factors) and high-risk T1 colorectal cancer (HRC; exhibiting lymphovascular invasion, tumor budding grade of 2/3, and/or poor differentiation) and studied predictive endoscopic factors for HRC.

RESULTS

Significant risk factors for LNM in multivariate analysis were lymphovascular invasion [odds ratio (OR) 8.09; 95% confidence interval (CI) 3.84-17.1], tumor budding (OR 1.89; 95% CI 1.09-3.29), and histological differentiation (OR 2.09; 95% CI 1.12-3.89). The LNM-positive rate with only deep submucosal invasion was 1.6%. Significant predictive factors for HRC in multivariate analysis identified rectal tumor location (OR 1.92; 95% CI 1.35 -2.72, depression (OR 2.73; 95% CI 1.96 -3.80), protuberance within the depression (OR 2.58; 95% CI 1.39- 4.78), expansiveness (OR 2.39; 95% CI 1.27- 4.50), and loss of mucosal patterns (OR 1.90; 95% CI 1.20 -3.01) as significant factors.

CONCLUSIONS

Rectal tumor location, depression, protuberance within the depression, expansiveness, and loss of mucosal patterns could be predictive factors for HRC.

Prognostic significance of lymphovascular invasion in colorectal cancer and its association with genomic alterations

BACKGROUND

Lymphovascular invasion (LVI) is suggested to be an early and important step in tumor progression toward metastasis, but its prognostic value and genetic mechanisms in colorectal cancer (CRC) have not been well investigated.

AIM

To investigate the prognostic value of LVI in CRC and identify the associated genomic alterations.

METHODS

We performed a retrospective analysis of 1219 CRC patients and evaluated the prognostic value of LVI for overall survival by the Kaplan-Meier method and multivariate Cox regression analysis. We also performed an array-based comparative genomic hybridization analysis of 47 fresh CRC samples to examine the genomic alterations associated with LVI. A decision tree model was applied to identify special DNA copy number alterations (DCNAs) for differentiating between CRCs with and without LVI. Functional enrichment and protein-protein interaction network analyses were conducted to explore the potential molecular mechanisms of LVI.

RESULTS

LVI was detected in 150 (12.3%) of 1219 CRCs, and the presence was positively associated with higher histological grade and advanced tumor stage (both P < 0.001). Compared with the non-LVI group, the LVI group showed a 1.77-fold (95% confidence interval: 1.40-2.25, P < 0.001) increased risk of death and a significantly lower 5-year overall survival rate (P < 0.001). Based on the comparative genomic hybridization data, 184 DCNAs (105 gains and 79 losses) were identified to be significantly related to LVI (P < 0.05), and the majority were located at 22q, 17q, 10q, and 6q. We further constructed a decision tree classifier including seven special DCNAs, which could distinguish CRCs with LVI from those without it at an accuracy of 95.7%. Functional enrichment and protein-protein interaction network analyses revealed that the genomic alterations related to LVI were correlated with inflammation, epithelial-mesenchymal transition, angiogenesis, and matrix remodeling.

CONCLUSION

LVI is an independent predictor for survival in CRC, and its development may correlate with inflammation, epithelial-mesenchymal transition, angiogenesis, and matrix remodeling.

Young-age onset colorectal cancer in Brazil: Analysis of incidence, clinical features, and outcomes in a tertiary cancer center

BACKGROUND

Recent studies report increasing incidence of colorectal cancer (CRC) in the young-age population, but data concerning clinical behavior, pathologic findings, and prognosis are controversial for this group. Early recognition of CRC in young patients is a challenge and diagnosis at advanced stage is clearly associated with worse outcomes.

MATERIALS AND METHODS

We retrospectively reviewed medical records of 5806 patients diagnosed with CRC between January/2011 and November/2016 and identified 781 patients aged less than 50-years-old.

RESULTS

We found an absolute increasing in the incidence of CRC in patients <50 years old of 1.88%-2.23% annually, with a relative increasing of 35.3% between 2011 and 2016. Median age was 42 years, 57.4% were female and 20.9% reported family history of CRC. Left-sided tumors were more frequent and the majority of patients were symptomatic. The most common stages at diagnosis were III (34.1%) and IV (37.3%). The median overall survival (OS) for stage IV was 25 months (95% CI 20.7-29.3) and was not reached for Stages I-III (P < 0.001). Family history of CRC was independently associated with better OS in stage IV(P = 0.02). For stages I-III, wild-type KRAS, family history of CRC, and absence of angiolymphatic invasion were associated with better OS (P = 0.02, P = 0.01 and P < 0.001, respectively).

CONCLUSIONS

In our cohort, the incidence of early-onset CRC is increasing over the past years. Young patients were more likely to be diagnosed with metastatic disease, left-sided and/or rectum site and symptoms at presentation. These findings highlight the emerging importance of young-age onset CRC and the need to discuss strategies to early diagnosis.

National multicentric evaluation of quality of pathology reports for rectal cancer in France in 2016

The quality of pathologic assessment of rectal cancer specimens is crucial for treatment efficiency and survival. The Royal College of Pathologists (RCP) recommends evaluating the quality of the pathology report in routine practice using three quality indicators (QIs): the number of lymph nodes (LNs) analyzed (≥ 12), the rate of venous invasion (VI ≥ 30%), and peritoneal involvement (pT4a ≥ 10%). In this study, we evaluated the three QIs of the French national pathology reports and compared them with British guidelines and assessed the influence of neoadjuvant radiochemotherapy on QIs. From January 1 to December 31, 2016, all pathology reports for rectal adenocarcinoma were collected from French departments. Neoadjuvant radiochemotherapy included long-course radiotherapy with concomitant 5-FU-based chemotherapy. A total of 983 rectal cancer pathology reports were evaluated. A median of 15 LNs were analyzed and 81% of centers had ≥ 12 LNs. The rate of VI was 30% and 41% of centers had ≥ 30% VI. The rate of pT4a was 4% and 18% of centers reported ≥ 10% pT4a. None of the centers reached the threshold for the three QIs. All three QIs were lower after radiochemotherapy compared to surgery alone. In conclusion, in French routine practice, the values of two of the three QIs (LNs analyzed and VI) were globally in line with RCP guidelines. However, the rate of pT4a was very low, particularly after radiochemotherapy, suggesting its low value in rectal 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.

Early disease relapse in a patient with colorectal cancer who harbors genetic variants of DPYD, TYMS, MTHFR and DHFR after treatment with 5-fluorouracil-based chemotherapy

Background Early relapse in colorectal cancer (CRC) after curative resection is mainly attributed to the key determinants such as tumor histology, stage, lymphovascular invasion, and the response to chemotherapy. Case presentation Interindividual variability in the efficacy of adjuvant chemotherapy between patients receiving the same treatment may be ascribed to the patients' genetic profile. In this report, we highlight a clinical case of a patient with stage II CRC who relapsed within a short period after starting adjuvant chemotherapy and was later found to have multiple genetic polymorphisms in the DPYD, TYMS, MTHFR, and DHFR genes. Conclusions Based on the clinical data of the patient and the key role of these genes in 5-fluorouracil pathway, we hypothesize that these variants may contribute to the drug response and early relapse in CRC.

Prognostic Implications of Extranodal Extension in Relation to Colorectal Cancer Location

Purpose

Extranodal extension (ENE) is closely associated with the aggressiveness of both colon and rectal cancer. This study evaluated the clinicopathologic significance and prognostic impact of ENE in separate populations of patients with colon and rectal cancers.

Materials and Methods

The medical records of 2,346 patients with colorectal cancer (CRC) who underwent curative surgery at our institution between January 2003 and December 2011 were clinically and histologically reviewed.

Results

ENE was associated with younger age, advanced tumor stage, lymphovascular invasion (LVI), and perineural invasion (PNI) in both colon and rectal cancer. ENE rates differed significantly in patients with right colon (36.9%), left colon (42.6%), and rectal (48.7%) cancers (right vs. left, p=0.037; left vs. rectum, p=0.009). The 5-year disease-free survival (DFS) rate according to ENE status and primary tumor site differed significantly in patients with ENE-negative colon cancer (80.5%), ENE-negative rectal cancer (77.4%), ENE-positive colon cancer (68.6%), and ENE-positive rectal cancer (64.2%) (p<0.001). Multivariate analysis showed that advanced tumor stage, ENE, LVI, PNI, and absence of adjuvant chemotherapy were independently prognostic of reduced DFS in colon and rectal cancer patients.

Conclusion

ENE is closely associated with the aggressiveness of colon and rectal cancers, with its frequency increasing from the right colon to the left colon to the rectum. ENE status is a significant independent predictor of DFS in CRC patients irrespective of tumor location. ENE might be more related with distally located CRC.

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.

Lymphovascular invasion is a high risk factor for stage I/II colorectal cancer: a systematic review and meta-analysis

The prognostic value of lymphovascular invasion (LVI) in stage I/II colorectal cancer (CRC) does not reach a consensus. To systematically assess prognostic significance of LVI, databases of PubMed, Web of Science, and Embase were searched from inception up to 10 Dec 2016. The pooled hazard ratio (HR) and 95% confidence intervals (CI) were used to determine the prognostic effects. Nineteen relevant studies including 9881 total patients were enrolled. Our results showed that LVI is significantly associated with poor prognosis in overall survival (OS) (HR=2.15, 95 % CI=1.72–2.68, P < 0.01) and disease-free survival (DFS) (HR=1.73, 95% CI=1.50–1.99, P < 0.01), which is similar in stage II patients. Further subgroup analysis revealed that the significance of the association between LVI and worse prognosis in CRC patients is not affected by below factors, including geographic setting, LVI positive rate, treatment, tumor site, and quality of the study. The current meta-analysis suggests that LVI may be a poor prognostic factor for stage I/II CRC patients.

Emergency resection surgery for colorectal cancer: Patterns of recurrent disease and survival

AIM

To evaluate prognostic pathological factors associated with early metachronous disease and adverse long-term survival in these patients.

METHODS

Clinical and histological features were analysed retrospectively over an eight-year period for prognostic impact on recurrent disease and overall survival in patients undergoing curative resection of a primary colorectal cancer.

RESULTS

A total of 266 patients underwent curative surgery during the study period. The median age of the study cohort was 68 year (range 26 to 91) with a follow-up of 7.9 years (range 4.6 to 12.6). Resection was undertaken electively in 225 (84.6%) patients and emergency resection in 35 (13.2%). Data on timing of surgery was missing in 6 patients. Recurrence was noted in 67 (25.2%) during the study period and was predominantly early within 3 years (82.1%) and involved hepatic metastasis in 73.1%. Emergency resection (OR = 3.60, P = 0.001), T4 stage (OR = 4.33, P < 0.001) and lymphovascular invasion (LVI) (OR = 2.37, P = 0.032) were associated with higher risk of recurrent disease. Emergency resection, T4 disease and a high lymph node ratio (LNR) were strong independent predictors of adverse long-term survival.

CONCLUSION

Emergency surgery is associated with adverse disease free and long-term survival. T4 disease, LVI and LNR provide strong independent predictive value of long-term outcome and can inform surveillance strategies to improve outcomes.

Age-related rates of colorectal cancer and the factors associated with overall survival

Background

The purpose of this study was to identify differences in both demographic and pathologic factors associated with the age-related rates of colorectal cancer (CRC) and overall survival (OS).

Methods

The National Cancer Data Base (NCDB), 2004-2013, was queried for patients with CRC. Patients were stratified by age (≤50 vs. ≥60 years). Multivariable analysis was performed to identify factors associated with OS.

Results

A total of 670,030 patients were included; 488,121 with colon, and 181,909 with rectal or rectosigmoid cancer. For colon cancer, patients ≤50 years had higher proportions of pathologic stage III and IV disease than patients ≥60 (III: 33.7% vs. 28.6%, IV: 25.5% vs. 14.3%, respectively; P≤0.001). Similar differences were found for patients with rectal cancer (III: 35.8% vs. 28.6%, IV: 16.5% vs. 11.6%, respectively for age ≤50 and ≥60 years; P≤0.001). More aggressive pathologic factors were identified in the ≤50 cohort and were associated with worse OS, including higher tumor grade, lymphovascular invasion (LVI), perineural invasion (PNI), and elevated serum carcinoembryonic antigen (CEA). Disparities associated with OS were also identified for both colon and rectal cancer. For patients ≤50 with CRC, African-American and Hispanic race, lower income and lower education were associated with increased risk of mortality compared to the ≥60 cohort.

Conclusions

There are clear differences in biological factors and in racial and socioeconomic disparities of patients with early onset CRC. Earlier screening should be seriously considered in patients under 50 years who are African-American and Hispanic, as these populations present with more aggressive and advanced disease.

Casticin inhibits the epithelial-mesenchymal transition in ovarian carcinoma via the hedgehog signaling pathway

Casticin inhibits migration, invasion and induced apoptosis in numerous cancer cells; however, the Hedgehog (Hh) signaling pathway is a key factor in the epithelial-mesenchymal transition (EMT). The present study aimed to assess whether casticin affects the expression of members of the Hh signaling pathway and EMT effectors in ovarian carcinoma. The ovarian cancer SKOV3 cell line was incubated in the presence of various concentrations of casticin or cyclopamine. Next, the expression levels of the main Hh signaling effector glioma-associated oncogene-1 (Gli-1) and EMT-associated factors [Twist-related protein 1 (Twist1), E-cadherin and N-cadherin] were determined by western blotting and reverse transcription-quantitative polymerase chain reaction. Cell proliferation and growth were assessed using MTT and soft agar assays; cell migration and invasion was evaluated using an in vitro migration assay and a transwell invasion assay, respectively. Compared with control group values, Gli-1, Twist1 and N-cadherin expression levels were reduced, whereas E-cadherin levels were increased in the casticin- and cyclopamine-treated groups. Incubation with casticin or cyclopamine resulted in markedly reduced SKOV3 cell viability, migration and invasion, in a dose-dependent manner. To the best of our knowledge, the findings of the present study indicated for first time that casticin may inhibit EMT via Hh signaling in vitro, reducing the migratory ability of ovarian cancer cells.

Renal capsular invasion is a prognostic biomarker in localized clear cell renal cell carcinoma

Renal capsular invasion (RCI) and lymphovascular invasion (LVI) are potential prognostic factors of significance in renal cell carcinoma (RCC). We evaluated the independent prognostic implications of RCI and LVI in localized clear cell RCC based on a large multi-institutional cohort. 6, 849 patients who had undergone radical or partial nephrectomy for RCC were included. Associations between recurrence and RCI or LVI were analyzed by constructing statistical models that combined Cox proportional hazard regression and propensity score matching. To analyze RCI, 2, 733 patients including 603 patients with RCI were enrolled. To analyze LVI, 3, 586 patients including 121 patients with LVI were enrolled. Recurrence was observed in 75 (12.4%) patients with RCI and 134 (6.3%) patients without RCI. In all statistical models, RCI was significantly associated with an increased risk of recurrence. Recurrence was observed 29 (24.0%) patients with LVI and 207 (6.0%) patients without LVI. LVI was significantly associated with an increased risk of recurrence only in non-adjusted univariate models, but not in multivariate adjusted analysis or propensity score matching models. In conclusion, these findings suggest that RCI could be a significant risk factor for localized clear cell RCC recurrence. In contrast to RCI, LVI cannot be an independent prognostic variable.

Predictive relevance of lymphovascular invasion in T1 colorectal cancer before endoscopic treatment

BACKGROUND AND AIM

 The depth of tumor invasion is currently the only reliable predictive risk factor for lymph node metastasis before endoscopic treatment for colorectal cancer. However, the most important factor to predict lymph node metastasis has been suggested to be lymphovascular invasion rather than the depth of invasion. Thus, the aim of this study was to investigate the predictive relevance of lymphovascular invasion before endoscopic treatment.

METHODS

 The data on pT1 colorectal cancers that were resected endoscopically or surgically from 2007 to 2015 were retrospectively reviewed. The cases were categorized into two groups: positive or negative for lymphovascular invasion. The following factors were evaluated by univariate and multivariate analyses: age and sex of the patients; location, size, and morphology of the lesion; and depth of invasion.

RESULTS

 The positive and negative groups included 229 and 457 cases, respectively. Younger age ( P  < 0.01), smaller lesion size ( P  = 0.01), non-LST (LST: laterally spreading tumor) ( P  < 0.01), presence of depression ( P  < 0.01), and pT1b ( P  < 0.01) were associated with lymphovascular invasion. In multivariate analysis, younger age (comparing patients aged ≤ 64 years with those aged > 65 years, OR, 1.81; 95 %CI, 1.29 - 2.53), presence of depression (OR, 1.97; CI, 1.40 - 2.77), non-LST features (OR, 1.50; CI, 1.04 - 2.15), and pT1b (OR, 3.08; CI, 1.91 - 4.97) were associated with lymphovascular invasion.

CONCLUSION

 Younger age, presence of depression, T1b, and non-LST are associated with lymphovascular invasion. Therefore, careful pathological diagnosis and surveillance are necessary for lesions demonstrating any of these four factors.

A Novel T-Stage Classification System for Adrenocortical Carcinoma: Proposal from the US Adrenocortical Carcinoma Study Group

BACKGROUND

The 7th AJCC T-stage system for adrenocortical carcinoma (ACC), based on size and extra-adrenal invasion, does not adequately stratify patients by survival. Lymphovascular invasion (LVI) is a known poor prognostic factor. We propose a novel T-stage system that incorporates LVI to better risk-stratify patients undergoing resection for ACC.

METHOD

Patients undergoing curative-intent resections for ACC from 1993 to 2014 at 13 institutions comprising the US ACC Group were included. Primary outcome was disease-specific survival (DSS).

RESULTS

Of the 265 patients with ACC, 149 were included for analysis. The current T-stage system failed to differentiate patients with T2 versus T3 disease (p = 0.10). Presence of LVI was associated with worse DSS versus no LVI (36 mo vs. 168 mo; p = 0.001). After accounting for the individual components of the current T-stage system (size, extra-adrenal invasion), LVI remained a poor prognostic factor on multivariable analysis (hazard ratio 2.14, 95% confidence interval 1.05-4.38, p = 0.04). LVI positivity further stratified patients with T2 and T3 disease (T2: 37 mo vs. median not reached; T3: 36 mo vs. 96 mo; p = 0.03) but did not influence survival in patients with T1 or T4 disease. By incorporating LVI, a new T-stage classification system was created: [T1: ≤ 5 cm, (-)local invasion, (+/-)LVI; T2: > 5 cm, (-)local invasion, (-)LVI OR any size, (+)local invasion, (-)LVI; T3: > 5 cm, (-)local invasion, (+)LVI OR any size, (+)local invasion, (+)LVI; T4: any size, (+)adjacent organ invasion, (+/-)LVI]. Each progressive new T-stage group was associated with worse median DSS (T1: 167 mo; T2: 96 mo; T3: 37 mo; T4: 15 mo; p < 0.001).

CONCLUSIONS

Compared with the current T-stage system, the proposed T-stage system, which incorporates LVI, better differentiates T2 and T3 disease and accurately stratifies patients by disease-specific survival. If externally validated, this T-stage classification should be considered for future AJCC staging systems.

Identification of prognostic genes through expression differentiation during metastatic process in lung adenocarcinoma

Cancer is a highly complicated biological process due to large scale heterogeneity. Identification of differentially expressed genes between normal and cancer samples is widely utilized in the discovery of prognostic factors. In this study, based on RNA sequencing data of lung adenocarcinoma, we focused on the expression differentiation during confined (with neither lymph node invasion nor distant metastasis) primary tumors and lymphnode (with only lymph node invasion but not distant metastasis) primary tumors. The result indicated that differentially expressed genes during confined-lymphnode transition were more closely related to patient’s overall survival comparing with those identified from normal-cancer transition. With the aid of public curated biological network, we successfully retrieved the biggest connected module composed of 135 genes, of which the expression was significantly associated with patient’s overall survival, confirmed by 9 independent microarray datasets.

Identification of Recurrence-Predictive Indicators in Stage I Colorectal Cancer

BACKGROUND

Patients with stage I colorectal cancer (CRC) rarely experience recurrences; therefore, few risk factors for recurrence are known. This study was designed to evaluate oncologic outcomes of patients with stage I CRC and to identify risk factors for recurrence after curative surgery.

METHODS

A retrospective cohort of 860 patients from a single institution who underwent curative surgery for stage I CRC between July 1995 and June 2010 was enrolled. Patients who were diagnosed with hereditary, synchronous, or metachronous cancer and those who received preoperative chemoradiotherapy were excluded. Patients from whom fewer than 12 lymph nodes were retrieved were also excluded.

RESULTS

The 860 patients included 402 (46.7%) with colon tumors and 458 (53.3%) with rectal tumors. Thirty-five patients (4.1%) experienced recurrences; local and systemic recurrence rates were 1.1 and 3.0%, respectively. The 5-year overall survival and recurrence-free survival (RFS) rates were 93.5 ± 0.8% and 95.7 ± 0.8%, respectively. Multivariate analysis showed that preoperative serum carcinoembryonic antigen (CEA) concentration ≥6 ng/mL (hazard ratio [HR] 3.354, 95% confidence interval [CI] 1.373-8.195, p = 0.008) and lymphovascular invasion (LVI) (HR 2.676, 95% CI 1.097-6.531, p = 0.031) were independent risk factors for RFS.

CONCLUSIONS

The overall recurrence rate among patients with stage I CRC after curative surgery was 4.1%. Elevated serum CEA and LVI were significantly associated with recurrence. Large-scale, multicenter studies are needed to confirm the prognostic value of these risk factors.

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.

MicroRNA-186-5p overexpression modulates colon cancer growth by repressing the expression of the FAM134B tumour inhibitor

OBJECTIVES

The role and underlying mechanism of miR-186-5p in colorectal cancer remain unknown. The present study aims to examine the various cellular effects of miR-186-5p in the carcinogenesis of colorectal cancer. Also, the interacting targets and association of clinicopathological factors with miR-186-5p expression in patients with colorectal cancer were analysed.

METHODS

The miR-186-5p expression levels in colorectal cancer tissues (n=126) and colon cancer cell lines (n=3) were analysed by real-time PCR. Matched non-neoplastic colorectal tissues and a non-neoplastic colonic epithelial cell line were used as controls. Various in vitro assays such as cell proliferation, wound healing and colony formation assays were performed to examine the miR-186-5p specific cellular effects. Western blots and immunohistochemistry analysis were performed to examine the modulation of FAM134B, PARP9 and KLF7 proteins expression.

RESULTS

Significant high expression of miR-186-5p was noted in cancer tissues (p< 0.001) and cell lines (p<0.05) when compared to control tissues and cells. The majority of the patients with colorectal cancer (88/126) had shown overexpression of miR-186-5p. This miR-186-5p overexpression was predominantly noted with in cancer with distant metastasis (p=0.001), lymphovascular permeation (p=0.037), microsatellite instability (MSI) stable (p=0.015), in distal colorectum (p=0.043) and with associated adenomas (p=0.047). Overexpression of miR-186-5p resulted in increased cell proliferation, colony formation, wound healing capacities and induced alteration of cell cycle kinetics in colon cancer cells. On the other hand, inhibition of endogenous miR-186-5p reduced the cancer growth properties. miR-186-5p overexpression reduced FAM134B expression significantly in the cancer cells (p<0.01). Also, FAM134B and miR-186-5p expressions are inversely correlated in colorectal cancer tissues and cells.

CONCLUSION

The miR-186-5p expression promotes colorectal cancer pathogenesis by regulating tumour suppressor FAM134B. Reduced cancer cells growth followed by inhibition of miR-186-5p highlights the potential of miR-186-5p inhibitor as a novel strategy for targeting colorectal cancer initiation and progression.

High miR-122 expression promotes malignant phenotypes in ccRCC by targeting occludin

Renal cell carcinoma (RCC) is the most common neoplasm of the adult kidney, and clear cell RCC (ccRCC) represents its most common histological subtype. Although several studies have reported high expression of miR-122 in ccRCC, its physiological role remains unclear. To clarify the role of miR-122 in ccRCC, we compared miR-122 expression levels in non-cancerous tissue and ccRCC. Significant upregulation of miR-122 was observed in ccRCC specimens. Moreover, ccRCC patients with high miR-122 expression showed poor progression-free survival compared to those with low miR-122 expression. Overexpression of miR-122 using an miRNA mimic promoted proliferation, migration, and invasion activities of ccRCC cells. miR-122 directly targets occludin, a known component of tight junctions. Occludin knockdown promoted the cell migration activity but not proliferation or invasion activities of ccRCC cells. In human clinical specimens, miR-122 expression inversely correlated with occludin protein expression. These findings show that miR-122 is an oncomiR in ccRCC.

Emergent Colectomy Is Independently Associated with Decreased Long-Term Overall Survival in Colon Cancer Patients

BACKGROUND

The purpose of this study was to examine the long-term overall survival (OS) of colon cancer patients who underwent emergent resection versus patients who were resected electively.

METHODS

The 2006-2012 National Cancer Data Base was queried for colon cancer patients who underwent surgical resection. Emergent resection was defined as resection within 24 h of diagnosis. A mixed-effects logistic regression was used to estimate the effect of emergent resection on 30- and 90-day mortality. A propensity score-matched mixed-effects Cox proportional-hazards model was used to estimate the effect of emergent resection on 5-year OS.

RESULTS

Two hundred fourteen thousand one hundred seventy-four patients met inclusion criteria, 30% of the cohort had an emergent resection. After controlling for patient and hospital factors, pathological stage, lymph node yield, margin status, and adjuvant chemotherapy, emergent resection was associated with increased odds of 30-day mortality (OR = 1.69, 95% CI = 1.60, 1.78) and hazard of death at 5 years (HR = 1.13, 95% CI = 1.09, 1.15) compared to elective resections.

CONCLUSION

Emergent resection for colon cancer is independently associated with poor short-term outcomes and decreased 5-year OS compared to elective resection. With 30% of cases in this study emergent, these findings underlie the importance of adherence to colon cancer screening guidelines to limit the need for emergent resections.

Genome-wide mutation profiles of colorectal tumors and associated liver metastases at the exome and transcriptome levels

To characterize the mutation profiles of colorectal cancer (CRC) primary tumors (PTs) and liver metastases (CLMs), we performed both whole-exome and RNA sequencing. Ten significantly mutated genes, including BMI1, CARD11, and NRG1, were found in 34 CRCs with CLMs. We defined three mutation classes (Class 1 to 3) based on the absence or presence of mutations during liver metastasis. Most mutations were classified into Class 1 (shared between PTs and CLMs), suggesting the common clonal origin of PTs and CLMs. Class 1 was more strongly associated with the clinical characteristics of advanced cancer and was more frequently superimposed with chromosomal deletions in CLMs than Class 2 (PT-specific). The integration of exome and RNA sequencing revealed that variant-allele frequencies (VAFs) of mutations in the transcriptome tended to have stronger functional implications than those in the exome. For instance, VAFs of the TP53 and APC mutations in the transcriptome significantly correlated with the expression level of their target genes. Additionally, mutations with high functional impact were enriched with high VAFs in the CLM transcriptomes. We identified 11 mutation-associated splicing events in the CRC transcriptomes. Thus, the integration of the exome and the transcriptome may elucidate the underlying molecular events responsible for CLMs.

Prognostic aspects of dynamic contrast-enhanced magnetic resonance imaging in synchronous distant metastatic rectal cancer

OBJECTIVES

To explore the correlations between DCE-MRI quantitative parameters and synchronous distant metastasis and the clinicopathological factors in rectal cancers.

METHODS

Sixty-three patients with rectal cancer (synchronous distant metastasis, n = 31; non-metastasis, n = 32) were enrolled in this study. Student's t test and ANOVA were used to compare DCE-MRI parameters (K ^trans , K _ep and V _e ). The receiver operating characteristic (ROC) analysis was used to find the reasonable threshold of DCE-MRI parameters to differentiate lesions with synchronous distant metastasis from those without metastasis.

RESULTS

The K ^trans , K _ep , and V _e value were significantly higher in the lesions with distant metastasis than in the lesions without distant metastasis (0.536 ± 0.242 vs. 0.299 ± 0.118 min^-1, p < 0.001; 1.598 ± 0.477 vs. 1.341 ± 0.390 min^-1, p = 0.022; and 0.324 ± 0.173 vs. 0.249 ± 0.091, p = 0.034; respectively). The K ^trans showed the highest AUCs of 0.788 (p < 0.001), with sensitivity of 61.29 % and specificity of 87.5 %, respectively.

CONCLUSIONS

DCE-MRI parameters may represent a prognostic indicator for synchronous distant metastases in patients with rectal cancer.

KEY POINTS

• The K ^trans , K _ep and V _e values correlated with synchronous distant metastasis. • Higher K ^trans , K _ep and V _e values were noted among patients with metastasis. • DCE-MRI parameters might represent a prognostic indicator for synchronous distant metastases.

Lymphovascular and perineural invasion are associated with poor prognostic features and outcomes in colorectal cancer: A retrospective cohort study

BACKGROUND

Lymphovascular and perineural invasion (LVI and PNI) are associated with poor outcomes in several cancers. We sought to identify clinical variables associated with LVI and PNI in colorectal cancer (CRC) and to determine their impact on survival.

METHODS

A retrospective review was performed of the National Cancer Data Base (NCDB), 2004-2011. Patients with CRC and a documented LVI or PNI status were included. Multivariate analysis was conducted to examine the associations between clinical variables and LVI/PNI, PNI and survival, and LVI/PNI and lymph node (LN) status in patients with T1 and T2 tumors.

RESULTS

In total, 158,777 patients were included. LVI status was documented for 139,026 patients, 26.3% of whom were positive. PNI status was documented in 142,034 patients, 11.1% of whom were positive. The multivariable model identified a number of pathologic and clinical characteristics associated with the presence of LVI and PNI, including a number of features of advanced CRC. PNI was independently associated with reduced survival (HR 3.55, 95%CI 1.78-7.09). In T1 or T2 tumors, LVI and PNI were significantly associated with LN involvement.

CONCLUSIONS

LVI and PNI are associated with advanced CRC. PNI is an independent poor prognostic marker for survival in CRC. LVI and PNI are associated with LN involvement in T1 and T2 tumors. Documentation of LVI and PNI status on biopsy specimens may help in prognostication and decision-making in the management of these early tumors.

Long-term outcomes of locally or radically resected T1 colorectal cancer

AIM

Little is known about the long-term outcome of T1 colorectal cancer (CRC) following curative resection. The present study addressed the long-term outcome of locally or radically resected T1 CRCs.

METHOD

A total of 430 patients with T1 CRC who underwent local or radical resection were considered. Unfavourable histological factors were defined as positive resection margin, deep submucosal invasion, vascular invasion, Grade 3 and budding. The patients were classified as low-risk (unfavourable histological factor negative, n = 65) or high-risk (unfavourable histological factor positive, n = 365).

RESULTS

Over a median follow-up of 78.4 months, disease recurred in 16 (3.7%) patients in the high-risk group, and no recurrence in the low-risk group. Resection type and vascular invasion were significantly associated with recurrence. In the vascular invasion (+) high-risk group, both 5-year disease-free survival rate and 5-year overall survival rate were significantly associated with resection type (radical 94.6%, local 43.8%, P < 0.001, and radical 99.1%, local 66.7%, P < 0.001). In the vascular invasion (-) high-risk group, 5-year disease-free survival rate was also significantly associated with resection type (radical 98.9%, local 84.7%, P = 0.001). However, 5-year overall survival rate was not associated with resection type (radical 98.9%, local 95.2%, P = 0.816).

CONCLUSION

Local resection may be effective and oncologically safe in low-risk T1 CRC. Although additional surgery should be recommended for the locally resected high-risk T1 CRC cases, intensive surveillance without additional surgery and timely salvage operation may offer another treatment option, if vascular invasion is negative.

Prognostic Factors in Terms of the Number of Metastatic Nodules in Patients With Colorectal Cancer Liver Metastases

Purpose

The hepatic resection is the gold-standard treatment for patients with colorectal-cancer liver metastases (CLM). This study aimed to identify prognostic factors in patients with synchronous CLM who underwent a surgical curative (R0) resection with respect to the number of metastatic nodules.

Methods

Of 1,261 CLM patients treated between January 1991 and December 2010, 339 who underwent a R0 resection for synchronous CLM were included in this retrospective analysis. Patients were grouped according to the number of CLM nodules: 1–2 CLM nodules, n = 272 (group 1) and 3–8 CLM nodules, n = 67 (group 2).

Results

The 5-year progression-free survival (PFS) rate in group 1was better than that in group 2 (P = 0.020). The multivariate analysis identified lymph-node metastasis (N2), lymphovascular invasion (LVI), and three or more CLM nodules as independent poor prognostic factors for PFS in all patients and lymph-node metastasis (N2) and LVI as independent poor prognostic factors for patients in group 1. No independent prognostic factors were identified for patients in group 2. CLM treatment method and neoadjuvant chemotherapy were not associated with survival.

Conclusion

Three or more metastatic nodules, lymph-node metastasis (N2), and LVI were independent poor prognostic factors for PFS in patients with synchronous CLM who underwent a R0 resection. The latter 2 factors were also independent prognostic factors for PFS in patients with less than 3 CLM nodules; however, in patients with three or more CLM nodules, the prognosis for PFS may be related only to liver metastasis.

Impact of tumor location on lymph node metastasis in T1 colorectal cancer

PURPOSE

Data evaluating the risk of lymph node metastasis depending upon the location of the primary tumor are limited in patients with T1 colorectal cancer. We aimed to evaluate the impact of tumor location on lymph node metastasis in T1 colorectal cancer.

METHODS

Patients who underwent an oncologic resection with curative intent for T1 adenocarcinoma of the colon and rectum between January 1997 and October 2014 were assessed. Exclusion criteria were distant organ metastases, previous or concurrent cancer, past history of surgical or medical cancer treatment, preoperative chemoradiation, and patients with inflammatory bowel disease or polyposis syndromes.

RESULTS

Out of 232 (56 % male) patients fulfilling the study criteria, 24 (10 %) had lymph node metastasis. Age (65 vs 61 years, p = 0.1), gender (55 vs 63 % male, p = 0.5), tumor size (2 vs 2 cm, p = 0.49), and lymphovascular invasion (5 vs 8 %, p = 0.46) were not associated with lymph node metastasis. While there was no statistical significance (p = 0.2), lymph node positivity was higher in rectal cancer (14 %, n = 11/79) compared to colon cancer (9 %, n = 13/153).

CONCLUSIONS

Although it was not statistically significant, lymph node positivity varies based on tumor location of T1 colorectal adenocarcinoma regardless of fundamental tumor characteristics including size, differentiation, and lymphovascular invasion.

Is lymphovascular invasion a powerful predictor for biochemical recurrence in pT3 N0 prostate cancer? Results from the K-CaP database

To assess the impact of lymphovascular invasion (LVI) on the risk of biochemical recurrence (BCR) in pT3 N0 prostate cancer, clinical data were extracted from 1,622 patients with pT3 N0 prostate cancer from the K-CaP database. Patients with neoadjuvant androgen deprivation therapy (n = 325) or insufficient pathologic or follow-up data (n = 87) were excluded. The primary endpoint was the oncologic importance of LVI, and the secondary endpoint was the hierarchical relationships for estimating BCR between the evaluated variables. LVI was noted in 260 patients (21.5%) and was significantly associated with other adverse clinicopathologic features. In the multivariate Cox regression analysis, LVI was significantly associated with an increased risk of BCR after adjusting for known prognostic factors. In the Bayesian belief network analysis, LVI and pathologic Gleason score were found to be first-degree associates of BCR, whereas prostate-specific antigen (PSA) level, seminal vesicle invasion, perineural invasion, and high-grade prostatic intraepithelial neoplasia were considered second-degree associates. In the random survival forest, pathologic Gleason score, LVI, and PSA level were three most important variables in determining BCR of patients with pT3 N0 prostate cancer. In conclusion, LVI is one of the most powerful adverse prognostic factors for BCR in patients with pT3 N0 prostate cancer.

A network-based analysis of colon cancer splicing changes reveals a tumorigenesis-favoring regulatory pathway emanating from ELK1

Splicing aberrations are prominent drivers of cancer, yet the regulatory pathways controlling them are mostly unknown. Here we develop a method that integrates physical interaction, gene expression, and alternative splicing data to construct the largest map of transcriptomic and proteomic interactions leading to cancerous splicing aberrations defined to date, and identify driver pathways therein. We apply our method to colon adenocarcinoma and non-small-cell lung carcinoma. By focusing on colon cancer, we reveal a novel tumor-favoring regulatory pathway involving the induction of the transcription factor MYC by the transcription factor ELK1, as well as the subsequent induction of the alternative splicing factor PTBP1 by both. We show that PTBP1 promotes specific RAC1,NUMB, and PKM splicing isoforms that are major triggers of colon tumorigenesis. By testing the pathway's activity in patient tumor samples, we find ELK1,MYC, and PTBP1 to be overexpressed in conjunction with oncogenic KRAS mutations, and show that these mutations increase ELK1 levels via the RAS-MAPK pathway. We thus illuminate, for the first time, a full regulatory pathway connecting prevalent cancerous mutations to functional tumor-inducing splicing aberrations. Our results demonstrate our method is applicable to different cancers to reveal regulatory pathways promoting splicing aberrations.

TNMF versus TNM in staging of colorectal cancer

AIM

TNM staging and histological grading of rectal cancer has undergone no or minimal changes during the past 20 years despite their major impact on planning, reporting and outcome of the disease. The addition of category 'F' to the 'TNM' staging of colorectal cancer, which becomes TNMF will accommodate the expanding list of risk factors that may affect the management and thus avoid squeezing them into the TNM categories.

METHODS

Reporting of the following risk factors was traced in 730 (664 retrospective and 66 prospective) cases of colorectal cancer: age, Tumor location, preoperative CEA, intraoperative tumor perforation and blood transfusion, quality of TME, tumor grade, non nodal T.Ds, Lymphovascular invasion, lymph node ratio, circumferential tumor margins, apical lymph nodes, infiltrating or pushing and K-ras gene mutation.

RESULTS

The reporting of most risk factors was inadequate; also there is marked improvement in reporting in the prospective cases in preoperative CEA, intra operative blood transfusion and tumor perforation, quality of TME, tumor grade and non-nodal T.Ds (P-value <0.0001).

CONCLUSION

The addition of category 'F' to the TNM staging system to become TNMF may avoid ignoring already established risk factors due to our inability to accommodate them in the inhospitable TNM categories.

Lymphovascular invasion status at transurethral resection of bladder tumors may predict subsequent poor response of T1 tumors to bacillus Calmette-Guérin

Background

Lymphovascular invasion (LVI) is an important step in the process of tumor dissemination and metastasis outside the primary organ, but the relationship between LVI and the prognosis of T1 non-muscle invasive bladder cancer (NMIBC) has not been fully evaluated. Accordingly, the present study was performed to evaluate whether LVI had an impact on the clinical outcome in patients with T1 NMIBC.

Methods

A total of 116 consecutive patients were diagnosed with T1 NMIBC from 1994 to 2013 at Keio University Hospital. All cases were reviewed by a single uro-pathologist. The prognostic significance of LVI was assessed in relation to recurrence and stage progression.

Results

The median follow-up period was 53 months. LVI was histologically confirmed in 30 patients (25.9%). There were no significant differences of clinical features between the patients with and without LVI. In T1 patients, univariate analysis demonstrated that LVI positivity was associated with stage progression (p = 0.003), but not with tumor recurrence (p = 0.192). Multivariate analysis confirmed that LVI was independently associated with stage progression (p = 0.006, hazard ratio = 4.00). In 85 patients who received BCG instillation, LVI was independently associated with both tumor recurrence and stage progression (p = 0.036 and 0.024, hazard ratio = 2.19 and 3.76).

Conclusions

LVI is a strong indicator of an increased risk of recurrence and progression in BCG-treated patients with T1 NMIBC. This information might assist clinicians to develop appropriate management and counseling strategies for these patients.

Prognostic and Predictive Model for Stage II Colon Cancer Patients With Nonemergent Surgery: Who Should Receive Adjuvant Chemotherapy?

No ideal prognostic model has been applied to clearly identify which suitable high-risk stage II colon cancer patients with negative margins undergoing nonemergent surgery should receive adjuvant chemotherapy routinely. Clinicopathologic and prognostic data of 333 stage II colon cancer patients who underwent D2 or D3 lymphadenectomy during nonemergent surgery were retrospectively analyzed. Four pathologically determined factors, including adjacent organ involvement (RR 2.831, P = 0.001), histologic differentiation (RR 2.151, P = 0.009), lymphovascular invasion (RR 4.043, P < 0.001), and number of lymph nodes retrieved (RR 2.161, P = 0.011), were identified as independent prognostic factors on multivariate analysis. Importantly, a simple cumulative scoring system clearly categorizing prognostic risk groups was generated: risk score = ∑ coefficient' × status (AOI + histological differentiated + lymphovascular invasion + LNs retrieved). Our new prognostic model may provide valuable information on the impact of lymphovascular invasion, as well as powerfully and reliably predicting prognosis and recurrence for this particular cohort of patients. This model may identify suitable patients with an R0 resection who should receive routine postoperative adjuvant therapy and may help clinicians to facilitate individualized treatment. In this study, we aim to provide an ideal and quantifiable method for clinical decision making in the nonemergent surgical treatment of stage II colon cancer. Our prognostic and predictive model should be applied in multicenter, prospective studies with large sample sizes, in order to obtain a more reliable clinical recommendation.

A genome wide association study on Newfoundland colorectal cancer patients' survival outcomes

Background

In this study we performed genome-wide association studies to identify candidate SNPs that may predict the risk of disease outcome in colorectal cancer.

Methods

Patient cohort consisted of 505 unrelated patients with Caucasian ancestry. Germline DNA samples were genotyped using the Illumina® human Omni-1quad SNP chip. Associations of SNPs with overall and disease free survivals were examined primarily for 431 patients with microsatellite instability-low (MSI-L) or stable (MSS) colorectal tumors using Cox proportional hazards method adjusting for clinical covariates. Bootstrap method was applied for internal validation of results. As exploratory analyses, association analyses for the colon (n = 334) and rectal (n = 171) cancer patients were also performed.

Results

As a result, there was no SNP that reached the genomewide significance levels (p < 5x10⁻⁸) in any of the analyses. A small number of genetic markers (n = 10) showed nominal associations (p <10⁻⁶) for MSS/MSI-L, colon, or rectal cancer patient groups. These markers were located in two non-coding RNA genes or intergenic regions and none were amino acid substituting polymorphisms. Bootstrap analysis for the MSS/MSI-L cohort data suggested the robustness of the observed nominal associations.

Conclusions

Likely due to small number of patients, our study did not identify an acceptable level of association of SNPs with outcome in MSS/MSI-L, colon, or rectal cancer patients. A number of SNPs with sub-optimal p-values were, however, identified; these loci may be promising and examined in other larger-sized patient cohorts.

Electronic supplementary material

The online version of this article (doi:10.1186/s40364-015-0031-6) contains supplementary material, which is available to authorized users.

Prognostic significance of the concomitant existence of lymphovascular and perineural invasion in locally advanced gastric cancer patients who underwent curative gastrectomy and adjuvant chemotherapy

OBJECTIVE

In this study, we evaluated the prognostic significance of the concomitant existence of lymphovascular invasion and perineural invasion in patients with advanced gastric cancer.

METHODS

A total of 206 consecutive patients with Stage II or III gastric cancer who underwent curative D2 gastrectomy and adjuvant chemotherapy from April 2004 to December 2011 were analyzed. Patients were classified into four groups according to the presence (+) or absence (-) of lymphovascular invasion and perineural invasion: lymphovascular invasion-/perineural invasion- (n = 33), lymphovascular invasion+/perineural invasion- (n = 31), lymphovascular invasion-/perineural invasion+ (n = 54) and lymphovascular invasion+/perineural invasion+ (n = 88).

RESULTS

A total of 136 patients (66.0%) received 5-fluorouracil plus cisplatin adjuvant chemotherapy and 70 patients (34.0%) received TS-1. During the median follow-up period of 35.18 months, the median disease-free survival times for lymphovascular invasion-/perineural invasion-, lymphovascular invasion+/perineural invasion- and lymphovascular invasion-/perineural invasion+ were not reached at the time of analysis; however, median disease-free survival for lymphovascular invasion+/perineural invasion+ was the worst (36.73 months, P = 0.001). The median overall survival in the four groups was also not reached at the time of analysis; however, median overall survival with lymphovascular invasion+/perineural invasion+ was the poorest (P = 0.002). In a multivariate analysis, lymphovascular invasion+/perineural invasion+ was an independent prognostic factor for both disease-free survival (hazard ratio = 1.940, 95% confidence interval 1.157-3.252, P = 0.012) and overall survival (hazard ratio = 2.973, 95% confidence interval 1.561-5.662, P = 0.001).

CONCLUSIONS

The concomitant existence of lymphovascular and perineural invasion has a significant prognostic impact on disease-free survival and overall survival in patients with Stage II or III gastric cancer.

MRI-detected extramural vascular invasion is an independent prognostic factor for synchronous metastasis in patients with rectal cancer

OBJECTIVES

To determine whether magnetic resonance imaging (MRI)-detected extramural vascular invasion (EMVI) could predict synchronous distant metastases in rectal cancer.

METHODS

Patients who underwent rectal MRI between July 2011 and December 2012 were screened. This study included 447 patients with pathologically confirmed rectal adenocarcinoma who had undergone MRI without previous treatment. Distant metastases were recorded at the initial work-up and over a 6-month follow-up. Univariate/multivariate logistic regression models were used to determine the risk of metastasis. The diagnostic performance was calculated using pathologic lymphovascular invasion (LVI) as a gold standard.

RESULTS

Among 447 patients, 79 patients (17.7 %) were confirmed to have distant metastases. Three MRI features are significantly associated with a high risk of distant metastasis: positive EMVI (odds ratio 3.02), high T stage (odds ratio 2.10) and positive regional lymph node metastasis (odds ratio 6.01). EMVI in a large vessel (≥3 mm) had a higher risk for metastasis than EMVI in a small vessel (<3 mm). Sensitivity, specificity and accuracy of MRI-detected EMVI were 28.2 %, 94.0 % and 80.3 %, respectively.

CONCLUSIONS

MRI-detected EMVI is an independent risk factor for synchronous metastasis in rectal cancer. EMVI in large vessels is a stronger risk factor for distant metastasis than EMVI in small vessels.

KEY POINTS

• EMVI, LN metastasis and T staging on MRI are risk factors for metastasis. • EMVI in large vessels has greater risk for metastasis than in small vessels. • Regional LN metastasis on MRI has highest risk for predicting metastasis. • MR findings could be helpful for selecting patients at high risk for metastasis.

Effect of skip lymphovascular invasion on hepatic metastasis in colorectal carcinomas

BACKGROUND

"Skip" lymphovascular invasion presenting as discontinuous foci of tumor cells within the colon wall is now excluded from consideration when determining T stage in the TNM classification. The purpose of this study was to assess the clinicopathological characteristics of colorectal cancer (CRC) patients with such skip lymphovascular invasion.

METHODS

First, a retrospective questionnaire survey of the incidence of skip lymphovascular invasion was performed for a total of 1,868 patients with CRCs at ten institutions. Next, we comparatively assessed clinicopathological data for 896 CRC patients with or without skip lymphovascular invasion.

RESULTS

The incidence of skip lymphovascular invasion was 1.1 % (20 out of 1,868). Most of the affected cases were rectal, pT2, and node negative, with moderately differentiated histology. Skip lymphovascular invasion was present in the muscularis propria and subserosa, with the tumors directly invading submucosa (pT1) or muscularis propria (pT2). Hepatic metastasis was greater in CRC with skip lymphovascular invasion (25 %) than in pT1/2 CRC (0 %; P < 0.001) or pT3 CRC without such invasion (13.8 %; P = 0.185).

CONCLUSIONS

Our study suggests that skip lymphovascular invasion is associated with hepatic metastasis in CRC cases. Thus, definition of a T category including such invasion would be useful for clinical practice.

Feasibility and survival of 2-stage hepatectomy for colorectal metastases: definition of a simple and early clinicopathologic predicting score

INTRODUCTION

Bilobar colorectal metastases may be treated by a 2-stage surgical strategy. The risk of drop out after the first stage hepatectomy remains high and is associated with a nearly zero survival rate at 3 years. Our goal was to evaluate the factors predictive of the feasibility of the strategy and long-term survival, based on simple clinical and histologic features obtained from the first stage specimen.

PATIENTS AND METHODS

Patients who underwent a first stage hepatectomy with curative intent were included. Preoperative clinical parameters and histologic features of the primary neoplasm and metastases obtained at the first stage hepatectomy were analyzed and compared between patients who did or did not undergo the second stage operation. A group of comparable patients treated only by chemotherapy was used as a control group.

RESULTS

The feasibility rate of this 2-stage resection was 76% (38/50 patients). Median survival was greater in patients treated with chemotherapy alone than for those who failed the second stage. A clinicopathologic score including male sex, segment 1 metastasis, need for >3 resection(s)/radiofrequency ablation(s), vascular invasion in the primary, need for change in type of chemotherapy, and microscopic biliary invasion by the metastasis was predictive of feasibility of the second stage and disease-free survival in patients achieving the second stage.

CONCLUSION

Combining preoperative clinical parameters with pathologic features of the primary and the metastatic lesions obtained during first stage hepatectomy predicted accurately patients who failed the second stage, and the long-term outcomes. Considering both clinical and pathologic parameters may help to define the best oncologic strategy by choosing between an exclusive chemotherapeutic or a surgical strategy.

Higher metastatic efficiency of KRas G12V than KRas G13D in a colorectal cancer model

Although all KRas (protein that in humans is encoded by the KRas gene) point mutants are considered to have a similar prognostic capacity, their transformation and tumorigenic capacities vary widely. We compared the metastatic efficiency of KRas G12V (Kirsten rat sarcoma viral oncogene homolog with valine mutation at codon 12) and KRas G13D (Kirsten rat sarcoma viral oncogene homolog with aspartic mutation at codon 13) oncogenes in an orthotopic colorectal cancer (CRC) model. Following subcutaneous preconditioning, recombinant clones of the SW48 CRC cell line [Kras wild-type (Kras WT)] expressing the KRas G12V or KRas G13D allele were microinjected in the mouse cecum. The percentage of animals developing lymph node metastasis was higher in KRas G12V than in KRas G13D mice. Microscopic, macroscopic, and visible lymphatic foci were 1.5- to 3.0-fold larger in KRas G12V than in KRas G13D mice (P < 0.05). In the lung, only microfoci were developed in both groups. KRas G12V primary tumors had lower apoptosis (7.0 ± 1.2 vs. 7.4 ± 1.0 per field, P = 0.02), higher tumor budding at the invasion front (1.2 ± 0.2 vs. 0.6 ± 0.1, P = 0.04), and a higher percentage of C-X-C chemokine receptor type 4 (CXCR4)-overexpressing intravasated tumor emboli (49.8 ± 9.4% vs. 12.8 ± 4.4%, P < 0.001) than KRas G13D tumors. KRas G12V primary tumors showed Akt activation, and β5 integrin, vascular endothelial growth factor A (VEGFA), and Serpine-1 overexpression, whereas KRas G13D tumors showed integrin β1 and angiopoietin 2 (Angpt2) overexpression. The increased cell survival, invasion, intravasation, and specific molecular regulation observed in KRas G12V tumors is consistent with the higher aggressiveness observed in patients with CRC expressing this oncogene.

Impact of perineural and lymphovascular invasion on oncological outcomes in rectal cancer treated with neoadjuvant chemoradiotherapy and surgery

BACKGROUND

The prognostic significance of perineural and/or lymphovascular invasion (PLVI) and its relationship with tumor regression grade (TRG) in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (CRT) and surgery.

METHODS

A total of 324 patients with LARC were treated with CRT and operated on between January 1992 and June 2007. Tumors were graded using a quantitative 5-grade TRG classification and the presence of PLVI was histologically studied.

RESULTS

At a median follow-up of 79.0 months (range 3-250 months), a total of 80 patients (24.7%) relapsed. The observed 5- and 10-year overall survival (OS) was 83.2 and 74.9 %, respectively. The 5- and 10-year disease-free survival (DFS) was 75.1 and 71.4%, respectively. A significant correlation was found between the TRG and survival (log rank, p < 0.001). The 10-year OS was 32.7% for grade 1, 63.8% for grade 2, 75.0% for grade 3, 90.4% for grade 3+, and 96.0%,for grade 4. The 10-year DFS was 31.8% for grade 1, 58.6% for grade 2, 70.4% for grade 3, 88.4% for grade 3+, and 97.1% for grade 4. In patients with PLVI, the TRG had no impact on survival. When excluding patients with PLVI, the TRG was an independent prognostic factor for OS and DFS.

CONCLUSIONS

The presence of PLVI is a more powerful prognostic factor than TRG in LARC patients treated with neoadjuvant CRT followed by surgery. PLVI denotes an aggressive phenotype, suggesting that these patients may benefit from adjuvant systemic therapy.

Tumour budding is a reproducible index for risk stratification of patients with stage II colon cancer

AIM

High-risk patients with Stage II colon cancer may benefit from adjuvant chemotherapy, but it is difficult to identify such a patient group. A robust and reproducible index would be helpful to select the subset of Stage II colon cancer patients at high risk. This study investigated the potential prognostic significance of tumour budding in Stage II colon cancer.

METHOD

In all, 135 Stage II colon cancer patients with known outcome were identified. The degree of tumour budding was assessed by two individual observers and was classified, according to the number of tumour buds in the area with the greatest budding intensity on haematoxylin and eosin slides, as high-grade budding (10 or more tumour buds) and low-grade budding (0-9 buds). Inter-observer agreement for two observers was assessed by using the kappa test. Progression-free and cancer-specific survivals were analysed using the Kaplan-Meier method and Cox regression.

RESULTS

The 5-year progression-free survival rates for patients with high-grade tumour budding (n = 36) and those with low-grade budding (n = 99) were 57.6% and 89.0% (P < 0.001). The 5-year cancer-specific survival rates were 66.7% vs 92.0% (P < 0.001). Cox regression analyses demonstrated tumour budding as an independent predictor of disease progression (hazard ratio 4.982, P < 0.001) and cancer-related death (hazard ratio 4.142, P = 0.003). The two observers agreed on the classification of tumour budding in 118 cases (87.4%) and the inter-observer agreement was good (κ = 0.692).

CONCLUSION

Tumour budding is a strong and reproducible prognostic factor for adverse outcome in Stage II colon cancer, which may serve as a prognostic marker to identify patients with a high risk of recurrence who may benefit from adjuvant therapy.

Long-term oncologic outcomes of laparoscopic versus open surgery for rectal cancer: a pooled analysis of 3 randomized controlled trials

OBJECTIVE

To compare long-term oncologic outcomes between laparoscopic and open surgery for rectal cancer and to identify independent predictors of survival.

BACKGROUND

Few randomized trials comparing laparoscopic and open surgery for rectal cancer have reported long-term survival data.

METHODS

Data from the 3 randomized controlled trials comparing curative laparoscopic (n=136) and open surgery (n=142) for upper, mid, and low rectal cancer conducted at the Prince of Wales Hospital, Hong Kong, between September 1993 and August 2007 were pooled together for this analysis. Survival and disease status were updated to February 2012. Survival was calculated using the Kaplan-Meier method, and independent predictors of survival were determined using the Cox regression analysis.

RESULTS

The demographic data of the 2 groups were comparable. The median follow-up time of living patients was 124.5 months in the laparoscopic group and 136.6 months in the open group. At 10 years, there were no significant differences in locoregional recurrence (5.5% vs. 9.3%; P=0.296), cancer-specific survival (82.5% vs. 77.6%; P=0.443), and overall survival (63.0% vs. 61.1%; P=0.505) between the laparoscopic and open groups. There was a trend toward lower recurrence rate at 10 years in the laparoscopic group than in the open group among patients with stage III cancer (P=0.078). The Cox regression analysis showed that stage III cancer, lymphovascular permeation, and blood transfusion, but not the operative approach, were independent predictors of poorer cancer-specific survival.

CONCLUSIONS

This pooled analysis with a follow-up of more than 10 years confirms the long-term oncologic safety of laparoscopic surgery for rectal cancer.

Lymphangiogenesis and lymphatic vessel remodelling in cancer

The generation of new lymphatic vessels through lymphangiogenesis and the remodelling of existing lymphatics are thought to be important steps in cancer metastasis. The past decade has been exciting in terms of research into the molecular and cellular biology of lymphatic vessels in cancer, and it has been shown that the molecular control of tumour lymphangiogenesis has similarities to that of tumour angiogenesis. Nevertheless, there are significant mechanistic differences between these biological processes. We are now developing a greater understanding of the specific roles of distinct lymphatic vessel subtypes in cancer, and this provides opportunities to improve diagnostic and therapeutic approaches that aim to restrict the progression of cancer.