Before doctors can prescribe new medications and treatments, they must be shown to be safe and effective. Colorectal cancerclinical trials allow test the effects of new medications on volunteers with colorectal cancer. The researchers follow a strict protocol and use carefully controlled conditions to evaluate the drugs being developed. The evaluation focuses on how well the drug treats colorectal cancer. Researchers also determine its safety and any possible side effects.
Some patients with colorectal...
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. Hepatic metastasis may be considered to be resectable based on the following:[17,21,24,25,26,27]
Limited number of lesions.
Intrahepatic locations of lesions.
Lack of major vascular involvement.
Absent or limited extrahepatic disease.
Sufficient functional hepatic reserve.
For patients with hepatic metastasis considered to be resectable, a negative margin resection has been associated with 5-year survival rates of 25% to 40% in mostly nonrandomized studies (such as the North Central Cancer Treatment Group trial, NCCTG-934653).[28,29,30,31,32][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:
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,[5,34] as well as improved survival and quality of life for patients receiving chemotherapy compared with best supportive care.[35,36,37] Several trials have analyzed the activity and toxic effects of various 5-FU-leucovorin (5-FU/LV) 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/LV.[39,40][Level of evidence: 1iiA]