[1] Biophotonics Research Unit, Gloucestershire Royal Hospital, Great Western Road, Gloucester GL13NN, United Kingdom
[2] Department of Histopathology, Gloucestershire Hospitals NHS Foundation Trust, United Kingdom
[3] Biomedical Imaging and Bio Sensing, School of Physics, University of Exeter, Exeter EX4 4QL, United Kingdom
[4] Three Counties Cancer Resection Unit, Upper Gastrointestinal Surgical Unit, Gloucestershire Hospitals NHS Trust, Gloucester GL13NN, United Kingdom
[5] Faculty of Bioscience and Medicine, Cranfield Health, Cranfield University, Bedfordshire, United Kingdom