Intra-tumour heterogeneity is one of the main sources of inter-observer variation in scoring stromal tumour infiltrating lymphocytes in triple negative breast cancer

Stromal tumour infiltrating lymphocytes (sTILs) are a strong prognostic marker in triple negative breast cancer (TNBC). Consistency scoring sTILs is good and was excellent when an internet-based scoring aid developed by the TIL-WG was used to score cases in a reproducibility study. This study aimed to evaluate the reproducibility of sTILs assessment using this scoring aid in cases from routine practice and to explore the potential of the tool to overcome variability in scoring. Twenty-three breast pathologists scored sTILs in digitized slides of 49 TNBC biopsies using the scoring aid. Subsequently, fields of view (FOV) from each case were selected by one pathologist and scored by the group using the tool. Inter-observer agreement was good for absolute sTILs (ICC 0.634, 95% CI 0.539–0.735, p < 0.001) but was poor to fair using binary cutpoints. sTILs heterogeneity was the main contributor to disagreement. When pathologists scored the same FOV from each case, inter-observer agreement was excellent for absolute sTILs (ICC 0.798, 95% CI 0.727–0.864, p < 0.001) and good for the 20% (ICC 0.657, 95% CI 0.561–0.756, p < 0.001) and 40% (ICC 0.644, 95% CI 0.546–0.745, p < 0.001) cutpoints. However, there was a wide range of scores for many cases. Reproducibility scoring sTILs is good when the scoring aid is used. Heterogeneity is the main contributor to variance and will need to be overcome for analytic validity to be achieved

Application of a risk-management framework for integration of stromal tumor-infiltrating lymphocytes in clinical trials

Stromal tumor-infiltrating lymphocytes (sTILs) are a potential predictive biomarker for immunotherapy response in metastatic triple-negative breast cancer (TNBC). To incorporate sTILs into clinical trials and diagnostics, reliable assessment is essential. In this review, we propose a new concept, namely the implementation of a risk-management framework that enables the use of sTILs as a stratification factor in clinical trials. We present the design of a biomarker risk-mitigation workflow that can be applied to any biomarker incorporation in clinical trials. We demonstrate the implementation of this concept using sTILs as an integral biomarker in a single-center phase II immunotherapy trial for metastatic TNBC (TONIC trial, NCT02499367), using this workflow to mitigate risks of suboptimal inclusion of sTILs in this specific trial. In this review, we demonstrate that a web-based scoring platform can mitigate potential risk factors when including sTILs in clinical trials, and we argue that this framework can be applied for any future biomarker-driven clinical trial setting

Investigating the prediction value of multiparametric magnetic resonance imaging at 3 T in response to neoadjuvant chemotherapy in breast cancer.

To explore the predictive value of parameters derived from diffusion-weighted imaging (DWI) and contrast-enhanced (CE)-MRI at different time-points during neoadjuvant chemotherapy (NACT) in breast cancer. Institutional review board approval and written, informed consent from 42 breast cancer patients were obtained. The patients were investigated before and at three different time-points during neoadjuvant chemotherapy (NACT) using tumour diameter and volume from CE-MRI and ADC values obtained from drawn 2D and segmented 3D regions of interest. Prediction of pathologic complete response (pCR) was evaluated using the area under the curve (AUC) of receiver operating characteristic analysis.There was no significant difference between pathologic complete response and non-pCR in baseline size measures (p>0.39). Diameter change was significantly different in pCR (p<0.02) before the mid-therapy point. The best predictor was lesion diameter change observed before mid-therapy (AUC=0.93). Segmented volume was not able to differentiate between pCR and non-pCR at any time-point. The ADC values from 3D-ROI were not significantly different from 2D data (p=0.06). The best AUC (0.79) for pCR prediction using DWI was median ADC measured before mid-therapy of NACT.The results of this study should be considered in NACT monitoring planning, especially in MRI protocol designing and time point selection

Investigating the prediction value of multiparametric magnetic resonance imaging at 3 T in response to neoadjuvant chemotherapy in breast cancer.

To explore the predictive value of parameters derived from diffusion-weighted imaging (DWI) and contrast-enhanced (CE)-MRI at different time-points during neoadjuvant chemotherapy (NACT) in breast cancer. Institutional review board approval and written, informed consent from 42 breast cancer patients were obtained. The patients were investigated before and at three different time-points during neoadjuvant chemotherapy (NACT) using tumour diameter and volume from CE-MRI and ADC values obtained from drawn 2D and segmented 3D regions of interest. Prediction of pathologic complete response (pCR) was evaluated using the area under the curve (AUC) of receiver operating characteristic analysis.There was no significant difference between pathologic complete response and non-pCR in baseline size measures (p>0.39). Diameter change was significantly different in pCR (p<0.02) before the mid-therapy point. The best predictor was lesion diameter change observed before mid-therapy (AUC=0.93). Segmented volume was not able to differentiate between pCR and non-pCR at any time-point. The ADC values from 3D-ROI were not significantly different from 2D data (p=0.06). The best AUC (0.79) for pCR prediction using DWI was median ADC measured before mid-therapy of NACT.The results of this study should be considered in NACT monitoring planning, especially in MRI protocol designing and time point selection

High MET expression is an adverse prognostic factor in patients with triple-negative breast cancer

Background: The mesenchymal-epithelial transition (MET) pathway is frequently altered in tumours. The purpose of our study was to determine the prognostic value of tumour MET expression levels in patients with triple-negative breast cancer (TNBC), in order to strengthen the rationale for targeted therapy of TNBC using MET inhibitors. Methods: We determined expression of MET in formalin-fixed paraffin-embedded surgical specimens of TNBC by immunohistochemistry. Recurrence-free and overall survival was analysed with Cox models adjusted for clinical and pathological factors.Results:Immunostaining for MET was classified as high in 89 of 170 (52%) tumours. MET expression was more frequently observed in G3 carcinomas (P=0.02) but was not significantly associated to any of the other clinical or pathological parameters. High MET expression predicted shorter survival of the patients. Multivariate Cox proportional hazards regression analyses identified MET to be an independent prognostic factor for recurrence (adjusted hazard ratio (HR) for recurrence 3.43; 95% confidence interval (CI) 1.65-7.12; P=0.001) and death (adjusted HR for death 3.74; 95% CI 1.65-8.46; P=0.002). Conclusion: These results provide further evidence that the MET pathway could be exploited as a target for TNBC. © 2013 Cancer Research UK. All rights reserved