Invasive colorectal cancer is a preventable disease. Early detection through widely applied screening programs is the most important factor in the recent decline of colorectal cancer in developed countries (see Deterrence/Prevention).
Full implementation of screening guidelines could cut mortality rate from colorectal cancer in the United States by an estimated additional 50%; even greater reductions are estimated for countries where screening tests may not be widely available at present. New and more comprehensive screening strategies are also needed.
Fundamental advances in understanding the biology and genetics of colorectal cancer are taking place. This knowledge is slowly making its way into the clinic and being employed to better stratify individual risks of developing colorectal cancer, discover better screening methodologies, allow for better prognostication, and improve the ability to predict benefit from new anticancer therapies.
In the past 10 years, an unprecedented advance in systemic therapy for colorectal cancer has dramatically improved outcome for patients with metastatic disease. Until the mid-1990s, the only approved agent for colorectal cancer was 5-fluorouracil. Since then, new agents in a variety of classes have become available, including the following:
- Cytotoxic agents (eg, irinotecan, oxaliplatin) 
- Oral fluoropyrimidines (ie, capecitabine and tegafur)
- Biologic agents (eg, bevacizumab, cetuximab, panitumumab) 
- Most recently, anti-angiogenic agents (ie, ziv-aflibercept, regorafenib)
Although surgery remains the definitive treatment modality, these new agents will likely translate into improved cure rates for patients with early-stage disease (stage II and III) and prolonged survival for those with stage IV disease. Further advances are likely to come from the development of new targeted agents and from better integration of systemic therapy with other modalities such as surgery, radiation therapy, and liver-directed therapies.
An image depicting standard colectomies for adenocarcinoma of the colon can be seen below.