1. Prognostic insights from multiplexed spatial profiling of the tumour microenvironment
- Author
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Tsakiroglou, Anna Maria, Fergie, Martin, Astley, Susan, Byers, Richard, West, Catharine, and Linton, Kim
- Subjects
Oropharyngeal cancer ,Multiplex immunofluorescence ,Digital pathology ,Spatial analysis ,Tumour microenvironment ,Follicular lymphoma - Abstract
Fulfilling the promise of cancer immunotherapy would benefit from novel biomarkers to characterise the tumour microenvironment and risk-stratify patients. Multiplex immunofluorescence imaging methods are suitable for this task, enabling visualisation of multiple proteins on the same tissue section. This facilitates identification of multiple cell phenotypes based on the proteins they express, while pre-serving spatial context. The aim of this thesis was to explore how multiplexed and spatial profiling of the tumour microenvironment in two types of cancer, oropharyngeal squamous cell carcinoma (OPSCC) and follicular lymphoma (FL), can be utilised for biomarker development. Computer assisted scoring tools are necessary to analyse multiplex images, as drawing conclusions from the large amount of information available is challenging. Thus, the first contribution of this work was to define design requirements of computer assisted scoring tools and assess their performance. Systematic review of the literature identified six design requirements: definability, accuracy, reproducibility, time-efficiency, interpretability and accurate confidence estimation. A meta-analysis of several HER2 and ER scoring studies established that automated scoring agreed with manual scoring, similar to how well pathologists usually agreed with each other. The second contribution of this work was the introduction of a prognostic biomarker in OPSCC using multiplex immunofluorescence and a new computer assisted scoring system to observe spatial proximity between cell phenotypes. Frequent spatial proximity between cells known to interact during the PD-1/PD-L1 immune escape pathway was unfavourable in patients with HPV negative OPSCC. The final contribution was the development and validation of a 7-plex immunofluorescent panel for FL and an automated scoring system to study the diversity of immune populations and their spatial relationships. Increased diversity of cell types and cell spatial interactions were favourable in multivariable analyses. These findings underline the importance of the tumour microenvironment in prognosis of FL and OPSCC and merit further exploration in additional cohorts. The design requirements identified can be applied to guide further validation and establish clinical applicability of the proposed automated scoring systems.
- Published
- 2021