Colorectal Cancer Risk

Behind lung cancer, colorectal cancer^[1] is the most common cause of cancer death and the fourth most common cancer after lung, breast, and prostate cancer. There were around 1.8 million cases of colorectal cancer worldwide in 2018, resulting in close to 900,000 deaths. Most colorectal cancer cases develop from benign tumors (adenoma) that undergo genetic changes^[2] over time (at least 10 years) to ultimately become cancerous (carcinoma). This process, often called the adenoma-carcinoma sequence, is depicted in Figure 1.

Figure 1: The adenoma-carcinoma sequence

Reference: Nguyen et al. Oncol Lett 2018 Jul.^[3]

Early detection^[4] through colonoscopy screenings is associated with reduced risk of recurrent colorectal cancer and death, and removal of colorectal adenomas appear to reduce the risk of colorectal cancer mortality^[5] and incidence^[6]. However, recurrence is common^[7].