The density of immune cells, called tumour infiltrating lymphocytes (TILs), when combined with analysis of tumour budding may serve as a method to more accurately predict survival in patients with stage III colon cancer, according to a team of researchers led by Mayo Clinic gastroenterologist and oncologist, Dr Frank Sinicrope.
In the study, ‘Analysis of tumor microenvironmental features to refine prognosis by T, N risk group in patients with stage III colon cancer’, published in the Annals of Oncology, the team used colon cancer tissues from a completed clinical trial and were able to demonstrate that the extent or density of TILs, reflecting the patient's anti-tumour immune response, is a robust predictor of survival in patients with stage III colon cancer. TILs are a type of immune cell that has moved from the blood into a tumour that can recognize and kill cancer cells.
"Our ability to predict patient outcome using TILs is strengthened when we combine it with tumour budding," explained Sinicrope.
Tumour budding is the presence of single cells or small clusters of tumour cells at the invasive margin, or front edge of a cancer, which can be scored by pathologists and may predict the potential for the cancer to metastasize.
"Determining the density of tumour infiltrating lymphocytes and analysis of tumour budding can be performed on resected tumour specimens," added Sinicrope. "We found that the combination of these tumour features were second only to number of tumour-containing lymph nodes for predicting patient survival. Furthermore, these features provided important data on patient survival in patients categorized into low-risk and high-riskT and N stage groups which guide the recommendation to receive 3 or 6 months of chemotherapy after surgery."
Sinicrope and his colleagues are working to automate the scoring of TILs and tumour budding in tumours from patients with stage III colon cancer.
"We hope to provide important prognostic information on individual patient tumours using routine tissue sections without the need for the special stains typically used to identify specific immune cell types," he added.