Diagnostic concordance of reporting lymphovascular invasion in breast cancer

Development and Validation of a HER2-Low Focused Immunohistochemical Scoring System With High-Interobserver Concordance: The Australian HER2-Low Breast Cancer Concordance Study

The DESTINY Breast-04 trial revealed survival advantages of trastuzumab deruxtecan for women with metastatic HER2-low breast cancer (1+ or 2+ immunohistochemistry [IHC], without amplification). Although this trial applied the 2018 Americal Society of Clinial Oncology (ASCO)/College of American Pathologists (CAP) HER2 IHC scoring criteria, the subjectivity and imprecision in IHC scoring have raised concerns that patients' treatment may be misaligned. Our group of 9 experienced breast pathologists collated a deidentified set of 60 breast cancer core biopsies from 3 laboratories, evaluated with the Ventana 4B5 HER2 assay and mostly scored locally as HER2 0 or 1+. Based on ASCO/CAP 2018 criteria and our extensive experience of reporting HER2 IHC, we specified scoring conventions for cancers with low levels of HER2 protein expression, articulating specific scoring pitfalls. Each pathologist then reviewed digitized whole slide images of the IHC slides and scored the HER2 expression for each case. At a subsequent consensus workshop, we reviewed the cases jointly to establish consensus scores for each case and determine the percentage of HER2 expressing tumor cells. Consensus was reached on all cases, with 40 classified as 1+ and 3 as 2+ (not amplified), totaling 43 (71.7%) HER2-low cancers. The remaining cases were HER2 0. In 93.3% of cases (56/60), the consensus score matched with the majority opinion of pathologists' independent scores. Seven (41.2%) of the 17 cases reported locally as HER2 0 were classified as HER2 low. Conversely, among 32 cases with local scores of 1+, 7 (21.8%) were reclassified as ultralow or null. Individual pathologists' accuracy in matching the consensus scores ranged from 73.3% to 91.67% (mean, 80.74%). Among HER2-low cancers those in which <20% of the tumor cells expressed HER2 had the lowest concordance levels. Observers Cohen's κ coefficients for concordance were excellent for 4, good in 1, and moderate in the 4 observers. This reference set of cases with expert consensus HER2 scores will be invaluable for peer training and development of our national external quality assurance program for HER2-low cancers. For assessing breast cancers at the low end of HER2 protein expression, our targeted scoring criteria and explicit instruction on pitfalls improved pathologists' accuracy and concordance.

Machine learning based on optimal VOI of multi-sequence MR images to predict lymphovascular invasion in invasive breast cancer

Objectives

Lymphovascular invasion serves as a crucial prognostic indicator in invasive breast cancer, influencing treatment decisions. We aimed to develop a machine learning model utilizing optimal volumes of interest extracted from multisequence magnetic resonance images to predict lymphovascular invasion in patients with invasive breast cancer.

Materials and methods

This study comprised 191 patients postoperatively diagnosed with invasive breast cancer through multi-sequence magnetic resonance imaging. Independent predictors were identified through univariate and multivariate logistic regression analyses, culminating in the construction of a clinical model. Radiomic features were extracted from multi-sequence magnetic resonance imaging images across various volume of interest scales (-2 mm, entire, +2 mm, +4 mm, and +6 mm). Subsequently, various radiomic models were developed using machine learning model algorithms, including logistic regression, support vector machine, k-nearest neighbor, gradient boosting machine, classification and regression tree, and random forest. A hybrid model was then formulated, amalgamating optimal radiomic and clinical models.

Results

The area under the curve of the clinical model was 0.757. Among the radiomic models, the most efficient diagnosis was achieved by the k-nearest neighbor-based radiomics-volume of interest (+2 mm), resulting in an area under the curve of 0.780. The hybrid model, integrating the k-nearest neighbor-based radiomics-volume of interest (+2 mm), and the clinical model surpassed the individual clinical and radiomics models, exhibiting a superior area under the curve of 0.864.

Conclusion

Utilizing a hybrid approach integrating clinical data and multi-sequence magnetic resonance imaging-derived radiomics models based on the multiscale tumor region volume of interest (+2 mm) proved effective in determining lymphovascular invasion status in patients with invasive breast cancer. This innovative methodology may offer valuable insights for treatment planning and disease management.

Prognostic value of histopathologic traits independent of stromal tumor-infiltrating lymphocyte levels in chemotherapy-naïve patients with triple-negative breast cancer

BACKGROUND

In the absence of prognostic biomarkers, most patients with early-stage triple-negative breast cancer (eTNBC) are treated with combination chemotherapy. The identification of biomarkers to select patients for whom treatment de-escalation or escalation could be considered remains an unmet need. We evaluated the prognostic value of histopathologic traits in a unique cohort of young, (neo)adjuvant chemotherapy-naïve patients with early-stage (stage I or II), node-negative TNBC and long-term follow-up, in relation to stromal tumor-infiltrating lymphocytes (sTILs) for which the prognostic value was recently reported.

MATERIALS AND METHODS

We studied all 485 patients with node-negative eTNBC from the population-based PARADIGM cohort which selected women aged <40 years diagnosed between 1989 and 2000. None of the patients had received (neo)adjuvant chemotherapy according to standard practice at the time. Associations between histopathologic traits and breast cancer-specific survival (BCSS) were analyzed with Cox proportional hazard models.

RESULTS

With a median follow-up of 20.0 years, an independent prognostic value for BCSS was observed for lymphovascular invasion (LVI) [adjusted (adj.) hazard ratio (HR) 2.35, 95% confidence interval (CI) 1.49-3.69], fibrotic focus (adj. HR 1.61, 95% CI 1.09-2.37) and sTILs (per 10% increment adj. HR 0.75, 95% CI 0.69-0.82). In the sTILs <30% subgroup, the presence of LVI resulted in a higher cumulative incidence of breast cancer death (at 20 years, 58%; 95% CI 41% to 72%) compared with when LVI was absent (at 20 years, 32%; 95% CI 26% to 39%). In the ≥75% sTILs subgroup, the presence of LVI might be associated with poor survival (HR 11.45, 95% CI 0.71-182.36, two deaths). We confirm the lack of prognostic value of androgen receptor expression and human epidermal growth factor receptor 2 -low status.

CONCLUSIONS

sTILs, LVI and fibrotic focus provide independent prognostic information in young women with node-negative eTNBC. Our results are of importance for the selection of patients for de-escalation and escalation trials.

MRI radiomics for the preoperative evaluation of lymphovascular invasion in breast cancer: A meta-analysis

PURPOSE

To evaluate the ability of preoperative MRI-based radiomic features in predicting lymphovascular invasion (LVI) in patients with breast cancer.

METHODS

PubMed, Embase, Web of Science, Cochrane Library databases, and four Chinese databases were searched to identify relevant studies published up until June 15, 2023. Two reviewers screened all papers independently for eligibility. We included diagnostic accuracy studies that used radiomics-MRI for LVI in patients with breast cancer, using histopathology as the reference standard. Quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 and Radiomics Quality Score. Overall diagnostic odds ratio (DOR), sensitivity, specificity and area under the curve (AUC) were calculated to assess the prediction efficacy of MRI-based radiomic features in patients with breast cancer. Spearman's correlation coefficient was calculated and subgroup analysis performed to investigate causes of heterogeneity.

RESULTS

Eight studies comprising 1685 female patients were included. The pooled DOR, sensitivity, specificity, and AUC of radiomics in detecting LVI were 23 [confidence interval (CI) 16,32], 0.89(0.86,0.92), 0.82 (0.78,0.86), and 0.83(0.78,0.87), respectively. The meta-analysis showed significant heterogeneity among the included studies. No threshold effect was detected. Subgroup analysis showed that more than 200 participants, radiomics with clinical factors, semiautomatic segmentation method and peritumoral or intra- and peritumoral model [DOR: 28(18,42), 26(19,37), 34(16,70), 40(10,156), respectively] could improve diagnostic performance compared with less than 200 participants, only radiomics, manual segmentation method, and tumor model [DOR: 16(7,37), 21(6,73), 20(12,32), 21(13,32), respectively], but 3.0 T MR and multiple sequences approach [DOR: 27(15,49),17(8,35)] couldn't improve diagnostic performance compared with 1.5 T and DCE radiomic features [DOR:27(7,99),25(17,37)].

CONCLUSION

Our meta-analysis showed that preoperative MRI-based radiomic features performs well in predicting LVI in patients with breast cancer. This noninvasive and convenient tool may be used to facilitate preoperative identification of LVI in breast cancer.

Using Machine Learning Methods to Assess Lymphovascular Invasion and Survival in Breast Cancer: Performance of Combining Preoperative Clinical and MRI Characteristics

BACKGROUND

Preoperative assessment of lymphovascular invasion (LVI) in invasive breast cancer (IBC) is of high clinical relevance for treatment decision-making and prognosis.

PURPOSE

To investigate the associations of preoperative clinical and magnetic resonance imaging (MRI) characteristics with LVI and disease-free survival (DFS) by using machine learning methods in patients with IBC.

STUDY TYPE

Retrospective.

POPULATION

Five hundred and seventy-five women (range: 24-79 years) with IBC who underwent preoperative MRI examinations at two hospitals, divided into the training (N = 386) and validation datasets (N = 189).

FIELD STRENGTH/SEQUENCE

Axial fat-suppressed T2-weighted turbo spin-echo sequence and dynamic contrast-enhanced with fat-suppressed T1-weighted three-dimensional gradient echo imaging.

ASSESSMENT

MRI characteristics (clinical T stage, breast edema score, MRI axillary lymph node status, multicentricity or multifocality, enhancement pattern, adjacent vessel sign, and increased ipsilateral vascularity) were reviewed independently by three radiologists. Logistic regression (LR), eXtreme Gradient Boosting (XGBoost), k-Nearest Neighbor (KNN), and Support Vector Machine (SVM) algorithms were used to establish the models by combing preoperative clinical and MRI characteristics for assessing LVI status in the training dataset, and the methods were further applied in the validation dataset. The LVI score was calculated using the best-performing of the four models to analyze the association with DFS.

STATISTICAL TESTS

Chi-squared tests, variance inflation factors, receiver operating characteristics (ROC), Kaplan-Meier curve, log-rank, Cox regression, and intraclass correlation coefficient were performed. The area under the ROC curve (AUC) and hazard ratios (HR) were calculated. A P-value <0.05 was considered statistically significant.

RESULTS

The model established by the XGBoost algorithm had better performance than LR, SVM, and KNN models, achieving an AUC of 0.832 (95% confidence interval [CI]: 0.789, 0.876) in the training dataset and 0.838 (95% CI: 0.775, 0.901) in the validation dataset. The LVI score established by the XGBoost model was an independent indicator of DFS (adjusted HR: 2.66, 95% CI: 1.22-5.80).

DATA CONCLUSION

The XGBoost model based on preoperative clinical and MRI characteristics may help to investigate the LVI status and survival in patients with IBC.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

The clinical significance of cyclin B1 (CCNB1) in invasive breast cancer with emphasis on its contribution to lymphovascular invasion development

BACKGROUND

Lymphovascular invasion (LVI) is regulated through complex molecular mechanisms. Cyclin B1 (CCNB1) was previously determined as being associated with LVI using large cohorts of breast cancer (BC) and artificial neural network (ANN) technique. In this study, we aimed to assess the association between CCNB1 and LVI, other clinicopathological and other LVI-related biomarkers at the molecular (RNA transcriptomic) and proteomic levels in BC.

METHODS

Two transcriptomic BC cohorts (n = 2834) were used to assess the association between the expression of CCNB1 at the mRNA level and clinicopathological characteristics and patient outcome. Tissue microarrays (TMAs) from a well-characterised BC cohort (n = 2480) with long-term outcome were also used to assess the clinical significance of CCNB1 protein expression using immunohistochemistry.

RESULTS

High CCNB1 mRNA expression was associated with aggressive tumour behaviour, including LVI, larger size, higher tumour grade, high lymph nodal stage, hormonal receptor negativity, HER2 positivity and poor clinical outcome (all p < 0.0001). Similarly, high CCNB1 protein expression was associated with higher tumour grade, hormonal receptor negativity and HER2 positivity (all p < 0.0001). Additionally, there was a significant association between CCNB1- and LVI-related biomarkers including N-cadherin, P-cadherin and TWIST2 at the transcriptomic and proteomic level. Multivariate analysis revealed that CCNB1 was an independent predictor of shorter BC-specific survival (HR = 1.3; 95% CI 1.2-1.5; p = 0.010).

CONCLUSION

CCNB1 is a key gene associated with LVI in BC and has prognostic value. More functional studies are warranted to unravel the mechanistic role of CCNB1 in the development of LVI.

Cd34 Immunostaining Adds Specificity To Microvascular invasion Analysis in Hepatocellular Carcinoma

Introduction

Hepatocellular carcinoma is the most common primary neoplasia of the liver. Microvascular invasion predicts outcome and defines tumor staging. However, its diagnosis is still a challenge. The present study aims to evaluate inter and intraobserver agreement in identifying the presence of microvascular invasion using conventional and immunohistochemistry histology.

Methods

Three pathologists performed the analysis of 76 hepatocellular carcinoma explants to characterize the presence of microvascular invasion using the hematoxylin/eosin stain and immunohistochemistry for CD34. The evaluations were made individually, in two distinct moments. Results were analyzed by the Kappa's coefficient and ROC curves.

Results

Our study demonstrated similar agreement for microvascular invasion between hematoxylin/eosin and CD34 methods. However, the intraobserver agreement values for both methods were higher than the interobserver ones. The accuracy of CD34 in relation to hematoxylin/eosin by ROC curves in intraobserver analysis tends to a high specificity, ranging from 82.1 to almost 100%, with sensitivity of 46.9% to 81.1%. In interobserver analysis, CD34 also has a high specificity (84.3% to 85.5%) while its sensitivity is a little shorter (81.2% to 84.3%).

Conclusion

Intraobserver higher agreement allows us to suppose that pathologists employed own criteria to evaluate vascular invasion, reinforcing the need of standardization. ROC Curves analysis showed that the CD34 method is more specific than sensitive. Therefore, immunohistochemistry for CD34 should not be used routinely, but it could be useful to help confirming invasion previously seen by conventional histology.

Further predictive value of lymphovascular invasion explored via supervised deep learning for lymph node metastases in breast cancer

Lymphovascular invasion, specifically lymph-blood vessel invasion (LBVI), is a risk factor for metastases in breast invasive ductal carcinoma (IDC) and is routinely screened using hematoxylin-eosin histopathological images. However, routine reports only describe whether LBVI is present and does not provide other potential prognostic information of LBVI. This study aims to evaluate the clinical significance of LBVI in 685 IDC cases and explore the added predictive value of LBVI on lymph node metastases (LNM) via supervised deep learning (DL), an expert-experience embedded knowledge transfer learning (EEKT) model in 40 LBVI-positive cases signed by the routine report. Multivariate logistic regression and propensity score matching analysis demonstrated that LBVI (OR 4.203, 95% CI 2.809-6.290, P < 0.001) was a significant risk factor for LNM. Then, the EEKT model trained on 5780 image patches automatically segmented LBVI with a patch-wise Dice similarity coefficient of 0.930 in the test set and output counts, location, and morphometric features of the LBVIs. Some morphometric features were beneficial for further stratification within the 40 LBVI-positive cases. The results showed that LBVI in cases with LNM had a higher short-to-long side ratio of the minimum rectangle (MR) (0.686 vs. 0.480, P = 0.001), LBVI-to-MR area ratio (0.774 vs. 0.702, P = 0.002), and solidity (0.983 vs. 0.934, P = 0.029) compared to LBVI in cases without LNM. The results highlight the potential of DL to assist pathologists in quantifying LBVI and, more importantly, in exploring added prognostic information from LBVI.

Hematoxylin and eosin or double stain for CD34/SOX10: Which is better for the detection of lymphovascular invasion in cutaneous melanoma?

BACKGROUND

Lymphovascular invasion (LVI) is considered an unfavorable prognostic factor in cutaneous melanoma (CM). However, its detection by hematoxylin and eosin (H&E) is challenging, with discordant data about its association with clinical-pathological features and no previous studies investigating the inter- (IrOA) and intra-observer (IaOA) agreement. Herein, we tested H&E and double staining (DS) for CD34/SOX10 to detect the LVI in a cohort of 92 CMs, evaluating the IrOA, the IaOA, and the association with the other clinical-pathological features.

METHODS

Five authors independently evaluated 92 consecutive and retrospectively enrolled cases of CMs. We assessed the IrOA (Fleiss's Kappa/FK and intraclass correlation coefficient/ICC) and the IaOA (Cohen's Kappa/CK) with both H&E and CD34/SOX10. Furthermore, we compared the LVI assessment with the two stains and analyzed the association with other clinical-pathological features [χ2 tests for dichotomous and categorical data; Student t-test (normal distribution) and Mann-Whitney U-test (non-normal distribution) for continuous data].

RESULTS

The IrOA was almost identical with H&E (FK=0.446; ICC=0.805) and CD34/SOX10 (FK=0.454; ICC=0.810); by contrast, the IaOA was higher with H&E for one pathologist (CK: 0.809) and with CD34/SOX10 for the other one (CK: 0.563). Applying previously defined criteria, LVI was detected in 10 (9.2%) and 11 (10.1%) cases with H&E and CD34/SOX10, respectively (p = 1.000). Both H&E and CD34/SOX10 were significantly associated with vertical growth phase (H&E, p: 0.014; CD34/SOX10, p: 0.010), mitosis ≥ 1/mm2 (H&E, p: 0.000; CD34/SOX10, p: 0.004), pT (H&E, p: 0.000; CD34/SOX10, p: 0.001), Breslow thickness (H&E, p: 0.000; CD34/SOX10, p: 0.001), and lymph node and/or distant metastasis (H&E, p: 0.005; CD34/SOX10, p: 0.000); only H&E was associated with ulceration (p: 0.002) and distant metastasis (p: 0.000), conversely, only CD34/SOX10 was associated with lymph node metastasis (p: 0.003).

CONCLUSIONS

CD34/SOX10 does not improve the IrOA and the IaOA of the LVI assessment in CM; furthermore, H&E and CD34/SOX10 show a similar profile of association with the other unfavorable clinical-pathological features of CM. As result, CD34/SOX10 could be a redundant diagnostic tool if applied for the prognostic characterization of not-selected CM in a routine diagnostic scenario.

Lymphatic Endothelial Markers and Tumor Lymphangiogenesis Assessment in Human Breast Cancer

Metastasis via lymphatic vessels or blood vessels is the leading cause of death for breast cancer, and lymphangiogenesis and angiogenesis are critical prerequisites for the tumor invasion–metastasis cascade. The research progress for tumor lymphangiogenesis has tended to lag behind that for angiogenesis due to the lack of specific markers. With the discovery of lymphatic endothelial cell (LEC) markers, growing evidence demonstrates that the LEC plays an active role in lymphatic formation and remodeling, tumor cell growth, invasion and intravasation, tumor–microenvironment remodeling, and antitumor immunity. However, some studies have drawn controversial conclusions due to the variation in the LEC markers and lymphangiogenesis assessments used. In this study, we review recent findings on tumor lymphangiogenesis, the most commonly used LEC markers, and parameters for lymphangiogenesis assessments, such as the lymphatic vessel density and lymphatic vessel invasion in human breast cancer. An in-depth understanding of tumor lymphangiogenesis and LEC markers can help to illustrate the mechanisms and distinct roles of lymphangiogenesis in breast cancer progression, which will help in exploring novel potential predictive biomarkers and therapeutic targets for breast cancer.

Lymphovascular invasion has a significant prognostic impact in patients with early breast cancer, results from a large, national, multicenter, retrospective cohort study

Background

We determined the prognostic impact of lymphovascular invasion (LVI) in a large, national, multicenter, retrospective cohort of patients with early breast cancer (BC) according to numerous factors.

Patients and methods

We collected data on 17 322 early BC patients treated in 13 French cancer centers from 1991 to 2013. Survival functions were calculated using the Kaplan–Meier method and multivariate survival analyses were carried out using the Cox proportional hazards regression model adjusted for significant variables associated with LVI or not. Two propensity score-based matching approaches were used to balance differences in known prognostic variables associated with LVI status and to assess the impact of adjuvant chemotherapy (AC) in LVI-positive luminal A-like patients.

Results

LVI was present in 24.3% (4205) of patients. LVI was significantly and independently associated with all clinical and pathological characteristics analyzed in the entire population and according to endocrine receptor (ER) status except for the time period in binary logistic regression. According to multivariate analyses including ER status, AC, grade, and tumor subtypes, the presence of LVI was significantly associated with a negative prognostic impact on overall (OS), disease-free (DFS), and metastasis-free survival (MFS) in all patients [hazard ratio (HR) = 1.345, HR = 1.312, and HR = 1.415, respectively; P < 0.0001], which was also observed in the propensity score-based analysis in addition to the association of AC with a significant increase in both OS and DFS in LVI-positive luminal A-like patients. LVI did not have a significant impact in either patients with ER-positive grade 3 tumors or those with AC-treated luminal A-like tumors.

Conclusion

The presence of LVI has an independent negative prognostic impact on OS, DFS, and MFS in early BC patients, except in ER-positive grade 3 tumors and in those with luminal A-like tumors treated with AC. Therefore, LVI may indicate the existence of a subset of luminal A-like patients who may still benefit from adjuvant therapy.

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In a study of 17 322 early BC patients, LVI had a significant independent negative prognostic impact on survival.

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LVI negatively impacted survival in almost every patient category and cancer subtype, with and without AC.

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LVI did not have a negative survival impact in patients with ER+ grade 3 or with luminal A-like tumors with chemotherapy.

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Results suggest a possible benefit of AC in LVI-positive luminal A-like patients.

Lymphovascular invasion and risk of recurrence in papillary thyroid carcinoma

BACKGROUND

Lymphovascular invasion (LVI) is an established adverse prognostic factor in many cancers, however, there are few studies assessing its significance in papillary thyroid carcinoma (PTC). We aimed to determine if LVI is an independent prognostic factor in PTC.

METHODS

We conducted a single institution retrospective analysis of 610 patients with PTC treated between 1987 and 2016. LVI was defined as the presence or absence of cancer cells in blood vessels and/or lymphatics on histopathology. Multivariate Cox regression analysis was used to evaluate the association between LVI and recurrence-free survival (RFS).

RESULTS

The study cohort included 481 (78.9%) females and 129 (21.1%) males, with a median age of 47.6 years and median follow-up of 3.4 years. LVI was present in 56 (9.2%) patients and was associated with nodal metastases (P < 0.001), extrathyroidal extension (P < 0.001), extranodal extension (P < 0.001), multifocality (P = 0.018) and microscopic positive margins (P < 0.001). On univariate analysis, LVI was associated with reduced RFS (hazard ratio (HR) 2.3; 95% confidence interval (CI) 1.3-4.3; P = 0.007). However, after adjusting for nodal stage (pN0, pN1a, pN1b) there was no association between LVI and RFS (HR 1.3; 95% CI 0.7-2.5; P = 0.398). Similar results were obtained in full multivariate models adjusting for additional prognostic factors (HR 1.2; 95% CI 0.6-2.4; P = 0.627).

CONCLUSION

LVI is strongly associated with other adverse prognostic factors in PTC, particularly the presence and extent of nodal metastases. However, after adjusting for these, LVI is not an independent predictor of recurrence.

Integrin β4 Is an Effective and Efficient Marker in Synchronously Highlighting Lymphatic and Blood Vascular Invasion, and Perineural Aggression in Malignancy

Lymphovascular invasion (LVI) and perineural invasion (PNI) are 2 important pathologic parameters and need to be accurately assessed in multiple malignancies. Integrin β4, a member of the integrin family, has been reported to be positively expressed in vascular endothelia, peripheral nerves, and a collection of epithelia. However, little is known about the effectiveness of β4 immunostaining on the recognition of LVI and PNI. Herein, we explored the applicability of β4 immunostaining in stomach, thyroid, and breast cancers. Parallel immunostaining of D2-40, CD34, and S-100 was performed as controls for lymphatic endothelia, vascular endothelia, and neural fibers, respectively. The results demonstrated that β4 concurrently stained the lymphatic and vascular endothelia, and the peripheral nerves. Both LVI and PNI were clearly and accurately outlined by β4 immunostaining. β4 was also expressed in the majority of tumor cells, enabling recognition of LVI and PNI encroached by small tumor clusters. In contrast to D2-40 and CD34, β4 staining was not observed in stromal cells, and therefore it facilitated differentiation between the shrinkage cleft and LVI. According to our results, β4 staining strikingly increased the diagnostic accuracy and interobserver concordance for LVI and PNI compared with hematoxylin and eosin staining alone. Finally, the applicability of β4 was confirmed in 9 other types of malignancies, including cancers of the colon, prostate, esophagus, lung, kidney, uterus, tongue, bladder, and liver. Collectively, β4 is a reliable marker for synchronous detection and diagnosis of LVI and PNI.

Transcriptomic Profile of Lymphovascular Invasion, a Known Risk Factor of Pancreatic Ductal Adenocarcinoma Metastasis

Lymphovascular invasion (LVI) is an aggressive pathologic feature and considered a risk factor for distant metastasis. We hypothesized that pancreatic ductal adenocarcinomas (PDACs) with LVI are associated with shorter survival, as well as aggressive cancer biology and lymphangiogenesis in transcriptomic analysis. Utilizing the cancer genome atlas (TCGA)-PDAC cohort, we found that positive LVI was significantly associated with positive perineural invasion (PNI) (p = 0.023), and higher American Joint Committee on Cancer (AJCC) T (p = 0.017) and N (p < 0.001) categories. Furthermore, positive LVI was associated with shorter overall survival (OS) (p = 0.014) and was an independent risk factor of poor OS. Although there was no association between LVI status and lymphangiogenesis, epithelial-mesenchymal transition (EMT), or metastasis-related genes, Gene Set Enrichment Analysis revealed a strong association with cell-proliferation-related gene sets such as mitotic spindles (Normalized enrichment score (NES) = 1.76, p = 0.016) and G2/M checkpoints (NES = 1.75, p = 0.036), as well as with transforming growth factor beta (TGF-beta) signaling (NES = 1.61, p = 0.043), which is a known mechanism of metastasis in PDACs. In conclusion, positive LVI was an independent risk factor of poor OS in PDACs. We found that PDACs with LVI were possibly associated with accelerated cell proliferation and enhanced TGF-beta signaling independent of lymphangiogenesis. Transcriptomic profiling elucidates more precise tumor biology of LVI-positive PDACs.

Lymphovascular invasion in breast cancer is associated with gene expression signatures of cell proliferation but not lymphangiogenesis or immune response

BACKGROUND

While the prognostic relevance of lymphovascular invasion (LVI) in breast cancer is well known, its molecular biology is poorly understood. We hypothesized that pathologically determined LVI reflects molecular features of tumors and can be discerned from their genomic and transcriptomic profiles.

METHODS

LVI status and Nottingham histological scores of primary breast tumors of The Cancer Genome Atlas (TCGA) project were assessed from pathology reports; other clinical and molecular data were obtained from TCGA data portals and publications. Two independent datasets (GSE5460 and GSE7849) were combined and used for validation.

RESULTS

LVI status was determinable for 639 and 196 cases of the TCGA and validation cohorts, among whom LVI incidence was 37.8% and 37.2%, respectively. LVI was associated with high tumor Ki67 expression, advanced pathologic stage, and high Nottingham scores. LVI-positive cases had worse overall and progression-free survival regardless of cancer subtype. Surprisingly, in both cohorts, LVI was not associated with lymphangiogenesis or lymphatic vessel density as estimated from tumor expression of lymphatic endothelium-associated genes. LVI-positive tumors had higher genome copy number aberrations, aneuploidy, and homologous recombination defects, but not single-nucleotide variations or intra-tumor genome heterogeneity. Tumor immune cell composition and cytolytic activity was not associated with LVI status. On the other hand, expression of cell proliferation-related genes was significantly increased in LVI-positive tumors.

CONCLUSION

Our study suggests that breast cancer with LVI is a highly proliferative cancer, and it does not correlate with gene expression markers for lymphangiogenesis or immune response.

A key genomic subtype associated with lymphovascular invasion in invasive breast cancer

BACKGROUND

Lymphovascular invasion (LVI) is associated with the development of metastasis in invasive breast cancer (BC). However, the complex molecular mechanisms of LVI, which overlap with other oncogenic pathways, remain unclear. This study, using available large transcriptomic datasets, aims to identify genes associated with LVI in early-stage BC patients.

METHODS

Gene expression data from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) cohort (n = 1565) was used as a discovery dataset, and The Cancer Genome Atlas (TCGA; n = 854) cohort was used as a validation dataset. Key genes were identified on the basis of differential mRNA expression with respect to LVI status as characterised by histological review. The relationships among LVI-associated genomic subtype, clinicopathological features and patient outcomes were explored.

RESULTS

A 99-gene set was identified that demonstrated significantly different expression between LVI-positive and LVI-negative cases. Clustering analysis with this gene set further divided cases into two molecular subtypes (subtypes 1 and 2), which were significantly associated with pathology-determined LVI status in both cohorts. The 10-year overall survival of subtype 2 was significantly worse than that of subtype 1.

CONCLUSION

This study demonstrates that LVI in BC is associated with a specific transcriptomic profile with potential prognostic value.