Combined morphologic and molecular classification for predicting lymph node metastasis in early-stage colorectal adenocarcinoma

Composite scoring system and optimal tumor budding cut-off number for estimating lymph node metastasis in submucosal colorectal cancer

BACKGROUND

Tumor budding is associated with lymph node (LN) metastasis in submucosal colorectal cancer (CRC). However, the rate of LN metastasis associated with the number of tumor buds is unknown. Here, we determined the optimal tumor budding cut-off number and developed a composite scoring system (CSS) for estimating LN metastasis of submucosal CRC.

METHODS

In total, 395 patients with histologically confirmed T1N0-2M0 CRC were evaluated. The clinicopathological characteristics were subjected to univariate and multivariate analyses. The Akaike information criterion (AIC) values of the multivariate models were evaluated to identify the optimal cut-off number. A CSS for LN metastasis was developed using independent risk factors.

RESULTS

The prevalence of LN metastasis was 13.2%. Histological differentiation, lymphatic or venous invasion, and tumor budding were associated with LN metastasis in univariate analyses. In multivariate models adjusted for histological differentiation and lymphatic or venous invasion, the AIC value was lowest for five tumor buds. Unfavorable differentiation (odds ratio [OR], 8.16; 95% confidence interval [CI], 1.80-36.89), lymphatic or venous invasion (OR, 5.91; 95% CI, 2.91-11.97), and five or more tumor buds (OR, 3.01; 95% CI, 1.21-7.69) were independent risk factors. In a CSS using these three risk factors, the rates of LN metastasis were 5.6%, 15.5%, 31.0%, and 52.4% for total composite scores of 0, 1, 2, and ≥ 3, respectively.

CONCLUSIONS

For the estimation of LN metastasis in submucosal CRC, the optimal tumor budding cut-off number was five. Our CSS can be utilized to estimate LN metastasis.

Deep Submucosal Invasion Is Not an Independent Risk Factor for Lymph Node Metastasis in T1 Colorectal Cancer: A Meta-Analysis

BACKGROUND & AIMS

Deep submucosal invasion (DSI) is considered a key risk factor for lymph node metastasis (LNM) and important criterion to recommend surgery in T1 colorectal cancer. However, metastatic risk for DSI is shown to be low in the absence of other histologic risk factors. This meta-analysis determines the independent risk of DSI for LNM.

METHODS

Suitable studies were included to establish LNM risk for DSI in univariable analysis. To assess DSI as independent risk factor, studies were eligible if risk factors (eg, DSI, poor differentiation, lymphovascular invasion, and high-grade tumor budding) were simultaneously included in multivariable analysis or LNM rate of DSI was described in absence of poor differentiation, lymphovascular invasion, and high-grade tumor budding. Odds ratios (OR) and 95% CIs were calculated.

RESULTS

Sixty-seven studies (21,238 patients) were included. Overall LNM rate was 11.2% and significantly higher for DSI-positive cancers (OR, 2.58; 95% CI, 2.10-3.18). Eight studies (3621 patients) were included in multivariable meta-analysis and did not weigh DSI as a significant predictor for LNM (OR, 1.73; 95% CI, 0.96-3.12). As opposed to a significant association between LNM and poor differentiation (OR, 2.14; 95% CI, 1.39-3.28), high-grade tumor budding (OR, 2.83; 95% CI, 2.06-3.88), and lymphovascular invasion (OR, 3.16; 95% CI, 1.88-5.33). Eight studies (1146 patients) analyzed DSI as solitary risk factor; absolute risk of LNM was 2.6% and pooled incidence rate was 2.83 (95% CI, 1.66-4.78).

CONCLUSIONS

DSI is not a strong independent predictor for LNM and should be reconsidered as a sole indicator for oncologic surgery. The expanding armamentarium for local excision as first-line treatment prompts serious consideration in amenable cases to tailor T1 colorectal cancer management.

Classic and Novel Histopathologic Risk Factors for Lymph Node Metastasis in T1 Colorectal Cancer: A Systematic Review and Meta-analysis

BACKGROUND

Treatment of endoscopically resected T1 colorectal cancers is based on the risk of lymph node metastasis. Risk is based on histopathologic features, although there is lack of consensus as to what constitutes high-risk features.

OBJECTIVE

The purpose of this study was to conduct a systematic review and meta-analysis of histopathologic risk factors for lymph node metastasis.

DATA SOURCES

A search of MEDLINE, Embase, Scopus, and Cochrane controlled register of trials for risk factors for lymph node metastasis was performed from inception until August 2018.

STUDY SELECTION

Included patients must have had an oncologic resection to confirm lymph node status and reported at least 1 histopathologic risk factor.

INTERVENTION

Rates of lymph node positivity were compared between patients with and without risk factors.

MAIN OUTCOME MEASURES

We report the results of the meta-analysis as ORs.

RESULTS

Of 8592 citations, 60 met inclusion criteria. Pooled analyses found that lymphovascular invasion, vascular invasion, neural invasion, and poorly differentiated histology were significantly associated with lymph node metastasis, as were depths of 1000 µm (OR = 2.76), 1500 µm (OR = 4.37), 2000 µm (OR = 2.37), submucosal level 3 depth (OR = 3.08), and submucosal level 2/3 (OR = 3.08) depth. Depth of 3000 µm, Haggitt level 4, and widths of 3000 µm and 4000 µm were not significantly associated with lymph node metastasis. Tumor budding (OR = 4.99) and poorly differentiated clusters (OR = 14.61) were also significantly associated with lymph node metastasis.

LIMITATIONS

Included studies reported risk factors independently, making it impossible to examine the additive metastasis risk in patients with numerous risk factors.

CONCLUSIONS

We identified 1500 μm as the depth most significantly associated with lymph node metastasis. Novel factors tumor budding and poorly differentiated clusters were also significantly associated with lymph node metastasis. These findings should help inform guidelines regarding risk stratification of T1 tumors and prompt additional investigation into the exact contribution of poorly differentiated clusters to lymph node metastasis.

Lymphovascular Infiltration, Not Depth of Invasion, is the Critical Risk Factor of Metastases in Early Colorectal Cancer: Retrospective Population-based Cohort Study on Prospectively Collected Data, Including Validation

OBJECTIVE

To identify clinical and histopathological risk factors of LNM in T1 CRC.

SUMMARY OF BACKGROUND DATA

The requisite of additional surgery after locally resected T1 CRC is dependent on the risk of LNM. Depth of submucosal invasion is used as a key predictor of lymphatic metastases although data are conflicting on its actual impact.

METHODS

Retrospective population-based cohort study on prospectively collected data on all patients with T1 CRC undergoing surgical resection in Sweden, 2009-2017 and Denmark 2016-2018. The Danish cohort was used for validation. Potential risk factors of LNM investigated were; age, sex, tumor location, submucosal invasion, grade of differentiation, mucinous subtype, lymphovascular, and perineural invasion.

RESULTS

One hundred fifty out of the 1439 included patients (10%) had LNM. LVI (P < 0.001), perineural invasion (P < 0.001), mucinous subtype (P = 0.006), and age <60 years (P < 0.001) were identified as independent risk factors whereas deep submucosal invasion was only a dependent (P = 0.025) risk factor and not significant in multivariate analysis (P = 0.075). The incidence of LNM was 51/882 (6%) in absence of the independent risk factors. The Danish validation cohort, confirmed our findings regarding the role of submucosal invasion, LVI, and age.

CONCLUSIONS

This is a large study on LNM in T1 CRC, including validation, showing that LVI and perineural invasion, mucinous subtype, and low age constitute independent risk factors, whereas depth of submucosal invasion is not an independent risk factor of LNM. Thus, our findings provide a useful basis for management of patients after local excision of early CRC.

CD133+CD54+CD44+ circulating tumor cells as a biomarker of treatment selection and liver metastasis in patients with colorectal cancer

Introduction

Liver is the most common site of distant metastasis in colorectal cancer (CRC). Early diagnosis and appropriate treatment selection decides overall prognosis of patients. However, current diagnostic measures were basically imaging but not functional. Circulating tumor cells (CTCs) known as hold the key to understand the biology of metastatic mechanism provide a novel and auxiliary diagnostic strategy for CRC with liver metastasis (CRC-LM).

Results

The expression of CD133⁺ and CD133⁺CD54⁺CD44⁺ cellular subpopulations were higher in the peripheral blood of CRC-LM patients when compared with those without metastasis (P<0.001). Multivariate analysis proved the association between the expression of CD133⁺CD44⁺CD54⁺ cellular subpopulation and the existence of CRC-LM (P<0.001). The combination of abdominal CT/MRI, CEA and the CD133⁺CD44⁺CD54⁺ cellular subpopulation showed increased detection and discrimination rate for liver metastasis, with a sensitivity of 88.2% and a specificity of 92.4%. Meanwhile, it also show accurate predictive value for liver metastasis (OR=2.898, 95% C.I.1.374–6.110).

Materials and Method

Flow cytometry and multivariate analysis was performed to detect the expression of cancer initiating cells the correlation between cellular subpopulations and liver metastasis in patients with CRC. The receiver operating characteristic curves combined with the area under the curve were generated to compare the predictive ability of the cellular subpopulation for liver metastasis with current CT and MRI images.

Conclusions

The identification, expression and application of CTC subpopulations will provide an ideal cellular predictive marker for CRC liver metastasis and a potential marker for further investigation.

Predictive microRNAs for lymph node metastasis in endoscopically resectable submucosal colorectal cancer

Accurate prediction of regional lymph node metastasis (LNM) in endoscopically resected T1-stage colorectal cancers (CRCs) can reduce unnecessary surgeries. To identify miRNA markers that can predict LNM in T1-stage CRCs, the study was conducted in two phases; (I) miRNA classifier construction by miRNA-array and quantitative reverse transcription PCR (qRT-PCR) using 36 T1-stage CRC samples; (II) miRNA classifier validation in an independent set of 20 T1-stage CRC samples. The expression of potential downstream target genes of miRNAs was assessed by immunohistochemistry. In the discovery analysis by miRNA microarray, expression of 66 miRNAs were significantly different between LNM-positive and negative CRCs. After qRT-PCR validation, 11 miRNAs were consistently significant in the combined classifier construction set. Among them, miR-342-3p was the most significant one (P=4.3×10-4). Through logistic regression analysis, we developed a three-miRNA classifier (miR-342-3p, miR-361-3p, and miR-3621) for predicting LNM in T1-stage CRCs, yielding the area under the curve of 0.947 (94% sensitivity, 85% specificity and 89% accuracy). The discriminative ability of this system was consistently reliable in the independent validation set (83% sensitivity, 64% specificity and 70% of accuracy). Of the potential downstream targets of the three-miRNAs, expressions of E2F1, RAP2B, and AKT1 were significantly associated with LNM. In conclusion, this classifier can predict LNM more accurately than conventional pathologic criteria and our study results may be helpful to avoid unnecessary bowel surgery after endoscopic resection in early CRC.

Tumor budding as a risk factor for nodal metastasis in pT1 colorectal cancers: a meta-analysis

Worldwide, colorectal cancer (CRC) screening programs have significantly increased the detection of submucosal (pT1) adenocarcinoma. Completion surgery may be indicated after endoscopic excision of these potentially metastasizing early cancers. However, the postsurgical prevalence of nodal implants does not exceed 15%, leading to questions concerning the clinical appropriateness of any post-endoscopy surgery. Eastern scientific societies (Japanese Society for Cancer of the Colon-Rectum, in particular) include tumor budding (TB), defined as the presence of isolated single cancer cells or clusters of fewer than 5 cancer cells at the tumor invasive front, among the variables that must be included in histologic reports. In Western countries, however, no authoritative endorsements recommend the inclusion of TB in the histology report because of the heterogeneity of definitions and measurement methods as well as its apparent poor reproducibility. To assess the prognostic value of TB in pT1 CRCs, this meta-analysis evaluated 41 studies involving a total of 10137 patients. We observed a strong association between the presence of TB and risk of nodal metastasis in pT1 CRC. In comparing TB-positive (684/2401; 28.5%) versus TB-negative (557/7736; 7.2%) patients, the prevalence of nodal disease resulted in an odds ratio value of 6.44 (95% confidence interval, 5.26-7.87; P<.0001; I² = 30%). This increased risk of regional nodal metastasis was further confirmed after accounting for potential confounders. These results support the priority of histologically reporting TB in any endoscopically removed pT1 CRC to direct more appropriate patient management.

Patient gender as a factor associated with lymph node metastasis in T1 colorectal cancer: A systematic review and meta-analysis

Approximately 10% of patients with T1 colorectal cancer have lymph node metastases (LNM), requiring node dissection along with surgical resection. Patient gender was recently reported to affect the occurrence of LNM. The aim of the present study was to assess whether patient gender was predictive of LNM in T1 colorectal cancer. Public databases, including PubMed, EMBASE and the Cochrane Central Register of Controlled Trials were searched, using key terms related to 'T1 colorectal cancer' and 'lymph node'. All relevant studies reporting the adjusted odds ratio or risk ratio of LNM in relation to patient gender were included. The quality of the studies was classified according to the Quality in Prognostic Studies tool. A random-effects model was used and the quality of the evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. The initial database search identified 2,492 publications; of those, 36 studies reported unadjusted results. Of the 36 studies, 4 reported adjusted results and fulfilled the inclusion criteria for this meta-analysis: 3 studies were graded as having a moderate risk of bias, and 1 had a low risk of bias. The present meta-analysis demonstrated that female gender was associated with increased risk of LNM (risk ratio=2.45, 95% confidence interval: 1.03-3.88). The I² statistic was 0.901, classified as very low (+OOO) and was downgraded by the risk of bias, inconsistency and publication bias. In conclusion, female gender was found to be correlated with LNM in patients with T1 colorectal cancer.

Histomorphological Factors Predicting the Response to Neoadjuvant Chemotherapy in Triple-Negative Breast Cancer

Purpose

There is no standard targeted therapy for the treatment of triple-negative breast cancer (TNBC). Therefore, its management heavily depends on adjuvant chemotherapy. Using core needle biopsy, this study evaluated the histological factors of TNBC predicting the response to chemotherapy.

Methods

One hundred forty-three TNBC patients who received single-regimen neoadjuvant chemotherapy (NAC) with the combination of doxorubicin, cyclophosphamide, and docetaxel were enrolled. The core needle biopsy specimens acquired before NAC were used to analyze the clinicopathologic variables and overall performance of the predictive model for therapeutic response.

Results

Independent predictors of pathologic complete response after NAC were found to be higher number of tumor infiltrating lymphocytes (p=0.007), absence of clear cytoplasm (p=0.008), low necrosis (p=0.018), and high histologic grade (p=0.039). In the receiver operating characteristics curve analysis, the area under curve for the combination of these four variables was 0.777.

Conclusion

The present study demonstrated that a predictive model using the above four variables can predict therapeutic response to single-regimen NAC with the combination of doxorubicin, cyclophosphamide, and docetaxel in TNBC. Therefore, adding these morphologic variables to clinical and genomic signatures might enhance the ability to predict the therapeutic response to NAC in TNBC.

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.

Tumor budding in colorectal cancer--ready for diagnostic practice?

Tumor budding is an important additional prognostic factor for patients with colorectal cancer (CRC). Defined as the presence of single tumor cells or small clusters of up to 5 cells in the tumor stroma, tumor budding has been likened to an epithelial-mesenchymal transition. Based on well-designed retrospective studies, tumor budding is linked to adverse outcome of CRC patients in 3 clinical scenarios: (1) in malignant polyps, detection of tumor buds is a risk factor for lymph node metastasis indicating the need for colorectal surgery; (2) tumor budding in stage II CRC is a highly adverse prognostic indicator and may aid patient selection for adjuvant therapy; (3) in the preoperative setting, presence of tumor budding in biopsy material may help to identify high-risk rectal cancer patients for neoadjuvant therapy. However, lack of consensus guidelines for standardized assessment still limits reporting in daily diagnostic practice. This article provides a practical and comprehensive overview on tumor budding aimed at the practicing pathologist. First, we review the prognostic value of tumor budding for the management of colon and rectal cancer patients. Second, we outline a practical, evidence-based proposal for the assessment of tumor budding in the daily sign-out. Last, we summarize the current knowledge of the molecular characteristics of high-grade budding tumors in the context of personalized treatment approaches and biomarker discovery.