| [ Summary ] |
Colorectal cancer has been treated with surgery for many years. In Dukes' stage A, most of the cases can be cured with surgery alone. However, even if curative resection is performed, the recurrence rate is still high in advanced stages, such as Dukes' stage C. Several adjuvant therapies, including chemotherapy and radio therapy, combined with surgery, have been investigated. In Dukes' stage C, postoperative chemotherapy including 5-fluorouracil + levamisole and 5-fluorouracil+folinic acid can improve the 5 year-survival rate, as seen in randomized trials. In addition, preoperative radiotherapy can also improve the 5 year-survival rate for rectal cancer in randomized trials. Therefore, these are considered to be effective therapies at the present time. One randomized trial demonstrated improved survival rates with the monoclonal antibody that recognized surface glycoprotein of the tumor. This was used as an adjuvant therapy. Because about 60 percent of the cases cannot yet be cured with such adjuvant therapies, better adjuvant therapies should be developed. |