A new prognostic method, which would allow high-risk stage two cancer patients to be identified more accurately, has been created by researchers at the University of St Andrews.
The new method takes into consideration how the immune system interacts with aggressive tumour cells in patients with colorectal cancer.
Currently, the TNM staging system is used in the prognosis of colorectal cancer which provides information on the local spread and size of the tumour (T), whether it has spread to the lymph nodes (N) or has spread to distant organs (M). TNM staging has been the clinical gold-standard for cancer prognosis and clinical decision-making for many decades.
However, approximately 20 per cent of patients with TNM stage two colorectal cancer experience recurrence of the disease with fatal consequences. The new system of prognosis developed in St Andrews is believed to be more accurate than current prognostic staging systems specifically for these stage two patients.
The research, published today (Thursday 7 March 2019) in Cancer Immunology Research, a journal of the American Association for Cancer Research, examined specific cells of the immune system (lymphocytes) and how they react to a particular type of aggressive tumour cells (tumour budding).
Using both the information about tumour budding (small isolated cancer clusters) and the immune system, Inés Nearchou of the School of Medicine at the University created a new model to classify patients with a high risk of succumbing to disease and who might benefit from additional therapy.
PhD candidate Ms Nearchou said: “We believe that this methodology could be successfully applied to other types of tumour as both immune infiltration and tumour budding have shown to be promising in a number of other solid tumours.”
The research team, led by Dr Peter Caie, also of the School of Medicine, analysed data from 114 patients with stage two colorectal cancer who underwent surgical resection in Edinburgh between 2002 and 2003 to create their new model. Their method was then validated in two independent cohorts from Edinburgh and Japan.
Dr Caie said: “TNM staging only measures basic properties about the tumour itself and does not take into account specific cancer subpopulations, such as tumour buds, or the patient’s immune reaction to the cancer.
“In this new model, we not only measure tumour buds as well as the extent of lymphocyte reaction to the tumour, but their spatial interaction to each other, something that can only accurately be reported through an automated machine learning and image analysis workflow such as the one we applied here.”
The paper Automated Analysis of Lymphocytic Infiltration, Tumor Budding, and Their Spatial Relationship Improves Prognostic Accuracy in Colorectal Cancer is published in Cancer Immunology Research and is available online.
Issued by the University of St Andrews Communications Office.Research