Note: Some citations in the text of this section are followed by a level of evidence. The PDQ editorial boards use a formal ranking system to help the reader judge the strength of evidence linked to the reported results of a therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more information.)
Incidence and mortality
Colorectal cancer (CRC) is the third most common malignant neoplasm worldwide  and the second leading cause of cancer deaths (irrespective of gender) in the United States. It is estimated that there will be 141,210 new cases diagnosed in the United States in 2011 and 49,380 deaths due to this disease. Between 1998 and 2007, CRC incidence rates in the United States declined by 2.2% per year in women, and by 2.9% per year in men. For the...
Treatment of patients with recurrent or advanced colorectal cancer depends on the location of the disease. For patients with locally recurrent and/or liver-only and/or lung-only metastatic disease, surgical resection, if feasible, is the only potentially curative treatment.
Treatment of patients with recurrent or advanced colorectal cancer depends on the location of the disease. For patients with locally recurrent and/or liver-only and/or lung-only metastatic disease, surgical resection, if feasible, is the only potentially curative treatment. For patients with hepatic metastasis considered to be resectable (i.e., based on limited number of lesions, intrahepatic locations of lesions, lack of major vascular involvement, absent or limited extrahepatic disease, and sufficient functional hepatic reserve), a negative margin resection has been associated with 5-year survival rates of 25% to 40% in nonrandomized studies (such as the NCCTG-934653 trial).[24,25,26,27,28][Level of evidence: 3iiiDiv] Better surgical techniques and advances in preoperative imaging have improved patient selection for resection. In addition, multiple studies with multiagent chemotherapy have demonstrated that patients with metastatic disease isolated to the liver, which historically would be considered unresectable, can occasionally be made resectable after the administration of chemotherapy.
Currently, there are seven active and approved drugs for patients with metastatic colorectal cancer:
Currently, there are seven active and approved drugs for patients with metastatic colorectal cancer: 5-FU, capecitabine, irinotecan, oxaliplatin, bevacizumab, cetuximab, and panitumumab. When 5-FU was the only active chemotherapy drug, trials in patients with locally advanced, unresectable, or metastatic disease demonstrated partial responses and prolongation of the time-to-progression (TTP) of disease,[5,30] as well as improved survival and quality of life for patients receiving chemotherapy compared with best supportive care.[31,32,33] Several trials have analyzed the activity and toxic effects of various 5-FU-leucovorin regimens, using different doses and administration schedules, and showed essentially equivalent results with a median survival time in the 12-month range. Prior to the advent of multiagent chemotherapy, two randomized studies demonstrated that capecitabine was associated with equivalent efficacy when compared with the Mayo Clinic regimen of 5-FU-leucovorin.[35,36][Level of evidence: 1iiA]