{Reference Type}: Letter {Title}: Immune response in colorectal carcinoma: a review of its significance as a predictive and prognostic biomarker. {Author}: Bell PD;Pai RK; {Journal}: Histopathology {Volume}: 0 {Issue}: 0 {Year}: Jun 2022 27 {Factor}: 7.778 {DOI}: 10.1111/his.14713 {Abstract}: Colorectal carcinoma is a leading cause of cancer-related death worldwide. There is significant prognostic heterogeneity in stages II and III tumours, necessitating the development of new biomarkers to more clearly identify patients at risk of disease progression. Recently, the tumour immune environment, particularly the type and quantity of T lymphocytes, has been shown to be a useful biomarker in predicting prognosis for patients with colorectal carcinoma. In this review, the significance of the immune response in colorectal carcinoma, including its influence on prognosis and response to therapy, will be detailed.