title: Five-year results of a randomized controlled trial of adjuvant chemotherapy for curatively resected colorectal carcinoma. The Colorectal Cancer Chemotherapy Study Group of Japan.
abstract: 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.
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D004334:Drug Administration Schedule; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D016016:Proportional Hazards Models; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D015996:Survival Rate
chemical_list: D016685:Mitomycin; D005472:Fluorouracil