Medline ® Abstract for Reference 9
of 'Adjuvant chemotherapy for resected stage II colon cancer'
Five-year results of a randomized controlled trial of adjuvant chemotherapy for curatively resected colorectal carcinoma. The Colorectal Cancer Chemotherapy Study Group of Japan.
Jpn J Clin Oncol. 1995;25(3):91.
In order to evaluate the significance of postoperative adjuvant chemotherapy for colorectal carcinoma, the Colorectal Cancer Chemotherapy Study Group, from 140 leading hospitals in Japan, conducted a prospective, randomized, controlled trial on patients who had undergone curative resections for colorectal carcinomas during the period from February 1984, to December 1985. The regimens for colon cancer were, Arm I: mitomycin C [intraoperative portal vein bolus (12 mg/m2) + postoperative, twice weekly and then three times bimonthly for six months intermittent i.v. bolus (6 mg/m2)]+ 5-fluorouracil (5-FU) 200 mg/body/day p.o. for six months; Arm II: postoperative twice weekly and then three times bimonthly intermittent i.v. bolus mitomycin C (6 mg/m2) for six months + 5-FU 200 mg/body/day p.o. for six months; Arm III: surgery alone. The regimens for rectal cancer were, Arm IV: same as Arm I, with superior rectal artery infusion of the same mitomycin C dose instead of portal vein infusion; Arm V: same as Arm II; Arm VI: same as Arm III. Of 2001 collected cases, 1805 eligible cases (899 colon cancers and 906 rectal cancers) were analyzed. Significant differences in five-year survival rates were found between Arms IV and V and Arm VI [Arm IV: 70.7% (95% confidence interval (C.I.): 65.6-75.8%), P = 0.004 vs Arm V: 73.6% (68.5-78.7%), P = 0.000 vs Arm VI (control): 60.2% (54.5-65.9%)]. No significant difference in overall survival rate was found in the colon cancer patients [Arm I: 80.4% (75.7-85.1%), not significant (N.S.) vs Arm II: 82.1% (77.8-86.4%), N.S. vs Arm III (control): 79.5% (74.6-84.4%)]. When stratified into Dukes classes, however, Dukes C patients in Arm II showed a significantly improved survival rate compared with that of those in Arm III [Arm I: 72.6% (64.8-80.4%), N.S. vs Arm II: 75.0% (67.9-82.1%), P = 0.012 vs Arm III (control): 61.0% (51.4-70.6%)]. We conclude the adjuvant use of long term oral 5-FU and intermittent mitomycin C (i.v.) to improve the survival rate of patients with curatively resected rectal cancer. Further comparative study is, however, recommended to confirm the effectiveness of 5-FU alone and the combination of 5-FU and mitomycin C. Regional chemotherapy made no contribution to reducing an hepatic recurrence of colon cancer or a local recurrence of rectal cancer.