Pattern of Tumour Cell Migration as a Prognostic Parameter for Lymph Node Metastasis in HER2-Enriched Breast Cancer
Ioannis Roxanis, Jo Russell, Bernadette Lavery. Oxford University Hospitals NHS Trust and Oxford Biomedical Research Centre, Oxford, United Kingdom; Oxford Medical Genetics Laboratories, Oxford, United Kingdom; , Oxford, United Kingdom
Background: As standardisation of the definitions and methodologies of molecular classification is still suboptimal, histological features with prognostic significance are of interest not only for potential application in clinical practice but also as a tool for formation of testable hypotheses concerning the biology of breast cancer progression. In contrast to the relatively homogeneous morphology of special types, variation in the architectural arrangement of invasive tumour cells characterises invasive ductal carcinomas not otherwise specified. Such variability conceivably corresponds to differences in the transcriptomic profile.
Design: In the current study, we aimed to assess morphologically the potential prognostic significance of migration patterns in sections of HER2-enriched breast tumours. Aiming to estimate the propensity of invasive tumour cells to form large confluent sheets rather than invade as single cells or smaller clusters, we employed a semiquantitative collective migration (CM) scoring system that ranged from 0 to 10.
Results: Our main finding was that the subgroup with CMhigh migration pattern had significantly higher propensity for regional lymph node metastasis (61% vs 19%, p=0.0025). This difference was even more significant when cases with basal-like features and lobular type were excluded (80% vs 12.5%, p=0.000009).
The pattern of migration was a significant prognostic predictor for lymph node metastasis independent of the proliferative status or the size of the tumours.
Conclusions: The pattern of tumour cell migration in HER2-enriched breast cancers is significantly correlated with lymph node status. Confirmation of this finding would have significant clinical implication in planning axillary treatment. Furthermore, as nodal metastasis indicates both tumour chronology and tumour aggressiveness, our finding may facilitate formation of hypotheses regarding differential biological behaviour of tumours grouped within same histological and molecular subtype. The relevance of epithelial-mesenchymal transition and TGFβ signaling will be discussed.
Tuesday, March 5, 2013 1:00 PM
Poster Session IV # 49, Tuesday Afternoon