Colorectal cancer still remains the third cause of cancer death among cancer patients. Early diagnosis is crucial and they can be either endoscopic or with blood biomarkers. Endoscopic methods consist of gastroscopy and colonoscopy, however; in recent years, endoscopic ultrasound is being used. The microenvironment is very important for the successful delivery of the treatment. Several proteins and hormones play a crucial role in the efficiency of the treatment. In the current mini review we will focus on interferon-γ.