Randomized, controlled study of continuous 5-FU infusion starting immediately after curative surgery for advanced colorectal cancer. Final results of randomized trials by the National Surgical Adjuvant Study of Colorectal Cancer (NSAS-CC). An individual patient data meta-analysis of adjuvant therapy with uracil-tegafur (UFT) in patients with curatively resected rectal cancer. Adjuvant chemotherapy in colorectal cancer: a joint analysis of randomised trials by the Nordic Gastrointestinal Tumour Adjuvant Therapy Group. Effective surgical adjuvant therapy for high-risk rectal carcinoma. Efficacy of oral UFT as adjuvant chemotherapy to curative resection of colorectal cancer: multicenter prospective randomized trial. [Prospective controlled study on the usefulness of Carmofur as a postoperative adjuvant chemotherapy for colorectal cancer]. Adjuvant 5FU plus levamisole in colonic or rectal cancer: improved survival in stage II and III. [Cooperative study of surgical adjuvant chemotherapy for colorectal cancer (third report): five-year results. Cooperative Study Group of Surgical Adjuvant Chemotherapy for Colorectal Cancer in Japan]. Oral adjuvant chemotherapy with carmofur (HCFU) for colorectal cancer: five-year follow-up. Tokai HCFU Study Group--third study on colorectal cancer. Chemotherapy with preoperative radiotherapy in rectal 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. Postoperative adjuvant chemotherapy or radiation therapy for rectal cancer: results from NSABP protocol R-01. Adjuvant chemotherapy with 5-fluorouracil, vincristine and CCNU for patients with Dukes' C colorectal cancer. The Swedish Gastrointestinal Tumour Adjuvant Therapy Group. Randomised clinical trial of adjuvant postoperative RT vs. sequential postoperative RT plus 5-FU and levamisole in patients with stage II-III resectable rectal cancer: a final report. Adjuvant chemotherapy in cancer of the colon and rectum: demonstration of effectiveness of prolonged 5-FU chemotherapy in a prospectively controlled, randomized trial. Adjuvant chemotherapy versus observation in patients with colorectal cancer: a randomised study. Randomized controlled trial of the efficacy of adjuvant immunochemotherapy and adjuvant chemotherapy for colorectal cancer, using different combinations of the intracutaneous streptococcal preparation OK-432 and the oral pyrimidines 1-hexylcarbamoyl-5-fluorouracil and uracil/tegafur.
The usefulness of adjuvant chemotherapy started immediately following surgery was evaluated.
                A randomized clinical trial was performed on 133 patients with advanced colorectal cancer using oral anticancer agents with one-week continuous 5-FU infusion starting immediately after curative surgery. In Group A and Group B, 300 mg/day of HCFU was orally administered for two years starting two weeks after surgery, and in addition, 333 mg/m2/day of 5-FU was drip infused from the central vein for seven days from the day of surgery in Group B.
                For 1919 days after surgery, there were no significant intergroup differences in overall survival (OS) and disease-free survival (DFS), but OS and DFS in Group B rectal cancer patients were significantly better when compared to Group A rectal cancer patients. On the other hand, OS tended to be better in Group A colon cancer patients, but no significant intergroup differences were seen, while intergroup differences tended to be smaller when corrected for disease stage.
                Continuous 5-FU infusion starting immediately after curative surgery for colorectal cancer was safe. While further investigation is necessary to elucidate the degree of improvement in postoperative prognosis, the results of the present study suggest that continuous 5-FU infusion improves prognosis in advanced rectal cancer. In the latter 1990s, adjuvant chemotherapy for completely resected Stage III colorectal cancer remained controversial in Japan. We conducted two independent randomized controlled trials in patients with Stage III colon and rectal cancer.
                Patients were randomly assigned to receive surgery alone or surgery followed by treatment with UFT (400 mg/m²/day), given for five consecutive days per week for 1 year. The primary endpoint was relapse-free survival (RFS), and the secondary endpoint was overall survival (OS).
                A total of 334 patients with colon cancer and 276 with rectal cancer were enrolled. The patients' characteristics were similar between the UFT group and the Surgery-alone group. There was no significant difference in RFS or OS in colon cancer. In rectal cancer, however, RFS and OS were significantly better in the UFT group than in the Surgery-alone group. The only grade 4 toxicity in the UFT group was diarrhea, occurring in one patient with colon cancer and one patient with rectal cancer.
                Postoperative adjuvant chemotherapy with UFT is successfully tolerated and improves RFS and OS in patients with Stage III rectal cancer. In colon cancer, the expected benefits were not obtained (hazard ratio = 0.89). Uracil-Tegafur (UFT), an oral fluorinated pyrimidine chemotherapeutic agent, has been used for adjuvant chemotherapy in curatively resected colorectal cancer patients. Past trials and meta-analyses indicate that it is somewhat effective in extending survival of patients with rectal cancer. The objective of this study was to perform a reappraisal of randomised clinical trials conducted in this field. We designed an individual patient-based meta-analysis of relevant clinical trials to examine the benefit of UFT for curatively resected rectal cancer in terms of overall survival (OS), disease-free survival (DFS), and local relapse-free survival (LRFS). We analysed individual patient data of five adjuvant therapy randomised clinical trials for rectal cancer, which met the predetermined inclusion criteria. These five trials had a combined total of 2091 patients, UFT as adjuvant chemotherapy compared to surgery-alone, 5-year follow-up, intention-to-treat-based analytic strategy, and similar endpoints (OS and DFS). In a pooled analysis, UFT had significant advantage over surgery-alone in terms of both OS (hazard ratio, 0.82; 95% confidence interval (CI), 0.70-0.97; P=0.02) and DFS (hazard ratio, 0.73; 95%CI, 0.63-0.84; P<0.0001). This individual patient-based meta-analysis demonstrated that oral UFT significantly improves both OS and DFS in patients with curatively resected rectal cancer. Due to uncertainties regarding clinically meaningful gains from adjuvant chemotherapy after colorectal cancer surgery, several Nordic Groups in the early 1990s initiated randomised trials to prove or reject such gains. This report gives the joint analyses after a minimum 5-year follow-up. Between October 1991 and December 1997, 2 224 patients under 76 years of age with colorectal cancer stages II and III were randomised to surgery alone (n = 1 121) or adjuvant chemotherapy (n = 1 103) which varied between trials (5FU/levamisole for 12 months, n = 444; 5FU/leucovorin for 4-5 months according to either a modified Mayo Clinic schedule (n = 262) or the Nordic schedule (n = 397). Some centres also randomised patients treated with 5FU/leucovorin to+/-levamisole). A total of 812 patients had colon cancer stage II, 708 colon cancer stage III, 323 rectal cancer stage II and 368 rectal cancer stage III. All analyses were according to intention-to-treat. No statistically significant difference in overall survival, stratified for country or region, could be found in any group of patients according to stage or site. In colon cancer stage III, an absolute difference of 7% (p = 0.15), favouring chemotherapy, was seen. The present analyses corroborate a small but clinically meaningful survival gain from adjuvant chemotherapy in colon cancer stage III, but not in the other presentations. Radiation therapy as an adjunct to surgery for rectal cancer has been shown to reduce local recurrence but has not improved survival. In a previous study, combined radiation and chemotherapy improved survival significantly as compared with surgery alone, but not as compared with adjuvant radiation, which many regard as standard therapy. We designed a combination regimen to optimize the contribution of chemotherapy, decrease recurrence, and improve survival as compared with adjuvant radiation alone.
                Two hundred four patients with rectal carcinoma that was either deeply invasive or metastatic to regional lymph nodes were randomly assigned to postoperative radiation alone (4500 to 5040 cGy) or to radiation plus fluorouracil, which was both preceded and followed by a cycle of systemic therapy with fluorouracil plus semustine (methyl-CCNU).
                After a median follow-up of more than seven years, the combined therapy had reduced the recurrence of rectal cancer by 34 percent (P = 0.0016; 95 percent confidence interval, 12 to 50 percent). Initial local recurrence was reduced by 46 percent (P = 0.036; 95 percent confidence interval, 2 to 70 percent), and distant metastasis by 37 percent (P = 0.011; 95 percent confidence interval, 9 to 57 percent). In addition, combined therapy reduced the rate of cancer-related deaths by 36 percent (P = 0.0071; 95 percent confidence interval, 14 to 53 percent) and the overall death rate by 29 percent (P = 0.025; 95 percent confidence interval, 7 to 45 percent). Its acute toxic effects included nausea, vomiting, diarrhea, leukopenia, and thrombocytopenia. These effects were seldom severe. Severe, delayed treatment-related reactions, usually small-bowel obstruction requiring surgery, occurred in 6.7 percent of all patients receiving radiation, and the frequencies of these complications were comparable in both treatment groups.
                The combination of postoperative local therapy with radiation plus fluorouracil and systemic therapy with a fluorouracil-based regimen significantly and substantively improves the results of therapy for rectal carcinoma with a poor prognosis, as compared with postoperative radiation alone. The purpose of this study is to evaluate the efficacy of postoperative adjuvant chemotherapy using uracil and tegafur (UFT) for colorectal cancer.
                In a multicenter trial among 43 institutions for patients who underwent curative resection of Dukes' B or C colorectal cancer, a surgery alone group (control group) and a treatment group (UFT group) to which UFT was administered at 400 mg/day for 2 years following surgery were compared. A total of 320 patients were registered between March 1991 and April 1994, and 289 of these patients were analyzed as a full-analysis set.
                The 5-year disease-free survival rate was 75.7% in the UFT group and 60.1% in the control group, respectively, and the stratified log-rank test showed the statistical significance ( P=0.0081). This difference was marked in rectal cancer ( P=0.0016) and, in particular, the local recurrence was reduced. No significant difference was observed in the 5-year survival rate. The incidence of adverse reactions on administration of UFT was low, and there was no serious adverse reaction.
                It is suggested that the consecutive administration of UFT at 400 mg/day was an effective and highly safe therapeutic method as postoperative adjuvant chemotherapy for rectal cancer. A prospective controlled study, the 7th cooperative study of the Japanese Foundation for Multidisciplinary Treatment, was conducted to evaluate the usefulness of concomitant therapy with MMC + HCFU as a postoperative adjuvant therapy in patients with colorectal cancer who had undergone curative resection for a period of 2 years and 11 months from February, 1986. The Dukes B and C patients with colorectal cancer classified by macroscopic examination who had an intravenous MMC 6 mg/m2 on the day of operation and followed by oral HCFU for 12 months from 2 weeks after operation (Group X) were compared with patients who had operation only (Group Y). Some 978 patients with colon cancer and 713 patients with rectal cancer were enrolled in the study, 85 (5.0%) of whom were not eligible. The 5-year survival rate of Group X in colon cancer was 79.3% and that of Group Y was 76.4%: thus the survival rate of Group X was slightly better than that of Group Y, but no significant difference was found between the two groups. Subset analysis revealed that the survival rate of Group X in advanced cancer of stage III b + IV, according to the General Rules for Clinical and Pathological Studies on Cancer of the Colon, Rectum and Anus in Japan, was 62.4% and that of Group Y was 46.2%. Thus, the survival rate of Group X was significantly better than that of Group Y (logrank test: p = 0.035, generalized Wilcoxon test: p = 0.025). The disease-free survival rate was not significantly different between the groups with colon cancer and rectal cancer. The above results suggest that HCFU is useful for patients with a high risk of recurrence who had advanced colon cancer (stage III b + IV). However, additional prospective studies are required to verify them. Based on the first favourable results of adjuvant therapy of 5FU plus levamisole in Dukes C colonic cancer in 1990, we conducted a prospective trial. 1029 patients were randomised to receive one year 5FU plus levamisole or no further treatment following curative surgery for stage II or III colon (n = 730) or rectal cancer (n = 299). 45% were in stage II and 55% in stage III. With a median follow-up of 4 years and 9 months a significant reduction in odds of death (25%, SD 9%, P = 0.007) was observed for those with adjuvant treatment (65% at 5 year) compared to the observation group (55%). Improved relative survival was present in stage III (56% vs 44%), and in stage II patients (78% vs 70%). In rectal cancer a non-significant difference in disease-free or overall survival was observed. Distant metastases developed in 76%, while local recurrence alone occurred in 14%. An early start of adjuvant treatment (< 4 weeks) did not affect results. Compliance to 5FU plus levamisole was 69%. Severe toxicity did not occur. In conclusion, one year 5FU plus levamisole was of benefit in stage II and III colonic cancer; in rectal cancer a significant positive effect could not be demonstrated. A randomized controlled study was carried out by the envelope method with 491 institutions in participation across the country in order to find an optimal surgical adjuvant chemotherapy for curatively resected colorectal cancer. The schedules for drug administration were different in four districts: ACNU + Futraful (FT) group and FT alone group in the Hokkaido-Shikoku district; the same schedule groups plus untreated group in the Chubu-Kinki district; MMC+FT group, FT alone group in the Tohoku-Kanto district; and ADM+FT group and FT alone group in the Chugoku-Kyushu district. The numbers of patients admitted to this study were 2,450 cases with colon cancer and 2,456 cases met the evaluation criteria of this study. The 5-year survival rate on the whole did not differ from combination therapy to single drug therapy in either colon cancer or rectal cancer, but in Dukes C rectal cancer the five-year survival rate tended to be higher with the combination therapies. In n2 (+) or a2(s) rectal cancer in particular, combination therapies with MMC and FT and with ADM and FT achieved significantly higher five-year survival rate, and the rate of local recurrence was significantly lower with ADM+FT. A joint study was performed by the Tokai HCFU study group, which included seven institutions, to examine the value of oral administration of Carmofur (HCFU), a 5-fluorouracil (5-FU) derivative, for postoperative adjuvant chemotherapy in patients with colorectal cancer undergoing curative resection.
                The patients were divided into two groups, a control group receiving no HCFU and a group administered HCFU for 1 year, using a centralized registration system by telephone. Among 173 patients entered into this study, 159 evaluable cases were analyzed for evaluation of the drug.
                The cumulative 5-year disease-free rate of patients who received HCFU was significantly increased compared with the control group. In particular, the rate was much higher in patients with colon cancer. No severe side effects arose from adjuvant chemotherapy with HCFU.
                Adjuvant chemotherapy with oral HCFU appears to provide a useful and safe postoperative treatment. Preoperative radiotherapy is recommended for selected patients with rectal cancer. We evaluated the addition of chemotherapy to preoperative radiotherapy and the use of postoperative chemotherapy in the treatment of rectal cancer.
                We randomly assigned patients with clinical stage T3 or T4 resectable rectal cancer to receive preoperative radiotherapy, preoperative chemoradiotherapy, preoperative radiotherapy and postoperative chemotherapy, or preoperative chemoradiotherapy and postoperative chemotherapy. Radiotherapy consisted of 45 Gy delivered over a period of 5 weeks. One course of chemotherapy consisted of 350 mg of fluorouracil per square meter of body-surface area per day and 20 mg of leucovorin per square meter per day, both given for 5 days. Two courses were combined with preoperative radiotherapy in the group receiving preoperative chemoradiotherapy and the group receiving preoperative chemoradiotherapy and postoperative chemotherapy; four courses were planned postoperatively in the group receiving preoperative radiotherapy and postoperative chemotherapy and the group receiving preoperative chemoradiotherapy and postoperative chemotherapy. The primary end point was overall survival.
                We enrolled 1011 patients in the trial. There was no significant difference in overall survival between the groups that received chemotherapy preoperatively (P=0.84) and those that received it postoperatively (P=0.12). The combined 5-year overall survival rate for all four groups was 65.2%. The 5-year cumulative incidence rates for local recurrences were 8.7%, 9.6%, and 7.6% in the groups that received chemotherapy preoperatively, postoperatively, or both, respectively, and 17.1% in the group that did not receive chemotherapy (P=0.002). The rate of adherence to preoperative chemotherapy was 82.0%, and to postoperative chemotherapy was 42.9%.
                In patients with rectal cancer who receive preoperative radiotherapy, adding fluorouracil-based chemotherapy preoperatively or postoperatively has no significant effect on survival. Chemotherapy, regardless of whether it is administered before or after surgery, confers a significant benefit with respect to local control. (ClinicalTrials.gov number, NCT00002523 [ClinicalTrials.gov].).
                Copyright 2006 Massachusetts Medical Society. 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. Information is presented from 555 patients with Dukes B and C rectal cancers treated by curative resection who were entered into the National Surgical Adjuvant Breast and Bowel Project (NSABP) protocol R-01 between November 1977 and October 1986. Their average time on study was 64.1 months. The patients were randomized to receive no further treatment (184 patients), postoperative adjuvant chemotherapy with 5-fluorouracil, semustine, and vincristine (MOF) (187 patients), or postoperative radiation therapy (184 patients). The chemotherapy group, when compared with the group treated by surgery alone, demonstrated an overall improvement in disease-free survival (P = .006) and in survival (P = .05). Employing the proportional hazards model, a global test was used to determine the presence of treatment interactions. Investigation of stratification variables employed in this study indicated that sex, and to a lesser extent age and Dukes stage, made individual contributions to the disease-free survival and the survival benefit from chemotherapy. When evaluated according to sex, the benefit for chemotherapy at 5 years, both in disease-free survival (29% vs. 47%; P less than .001; relative odds, 2.00) and in survival (37% vs. 60%; P = .001; relative odds, 1.93), was restricted to males. When males were tested for age trend with the use of a logistic regression analysis, chemotherapy was found to be more advantageous in younger patients. When the group receiving post-operative radiation (4,600-4,700 rad in 26-27 fractions; 5,100-5,300 rad maximum at the perineum) was compared to the group treated only by surgery, there was an overall reduction in local-regional recurrence from 25% to 16% (P = .06). No significant benefit in overall disease-free survival (P = .4) or survival (P = .7) from the use of radiation has been demonstrated. The global test for interaction to identify heterogeneity of response to radiation within subsets of patients was not significant. In conclusion, this investigation has demonstrated a benefit from adjuvant chemotherapy (MOF) for the management of rectal cancer. The observed advantage was restricted to males. Postoperative radiation therapy reduced the incidence of local-regional recurrence, but it failed to affect overall disease-free survival and survival. A prospective controlled randomized trial testing adjuvant postoperative combination chemotherapy (5-fluorouracil, lomustine (CCNU) and vincristine) versus no adjuvant therapy in patients operated on for Dukes' C colorectal cancer is reported. In total 334 patients aged less than 70 years were recruited: 205 patients with colonic and 99 with rectal cancer, but there were three protocol violations and these cases are excluded from further consideration. Twenty-seven patients had a limited resection of their cancer. After 5 years' follow-up there was no significant difference in the tumour-free survival rate or in the survival rate between the treated and control groups. Twenty-nine of the 147 patients who started chemotherapy discontinued this treatment because of side-effects, mainly from the gastrointestinal tract. In 30 patients treatment was discontinued because of recurrent disease. The conclusion is that systemic administration of combination chemotherapy for colorectal cancer after operation is not worthwhile in routine clinical practice. A randomised clinical trial was performed in patients undergoing radical surgery for rectal cancer to compare the efficacy and toxicity of adjuvant postoperative radiation therapy (RT) to sequential RT and chemotherapy (CT) with 5-fluorouracil (5-FU) plus levamisole (LEV). The primary end point was overall survival (OS); secondary end points were disease-free survival (DFS), the rate of loco-regional recurrence, and treatment-related toxicity; the final results of this trial are reported.
                Patients in arm I underwent RT (50 Gy) in daily fractions of 2 Gy, 5 days/week for 5 weeks. Patients in arm II began with 5-FU (450 mg/sqm/day intravenous (i.v.) bolus, days 1-5) plus LEV (150 mg/day orally, days 1-3); postoperative RT was delivered during week 2 at the same dosage and schedule as in arm I. The other five cycles of CT (5-FU every 28 days and LEV every 15 days for the length of 5-FU administration) continued after the end of RT if clinical and hemato-biochemical parameters were in the normal range.
                From May 1992 to December 1998, 218 patients were enrolled into the randomised clinical trial (144 men, 74 women; age range: 28-75, median 64 years). The median follow-up time was 58.1 months (range: 1-3,271 days). No significant difference was observed between the two arms of treatment as regards OS and DFS (P = 0.18 and P = 0.66, respectively). Cox regression analysis for OS confirmed what was observed by univariate analysis for all variables except age. Older age (>60 years) and pathologic lymph-node involvement defined the subgroups with the worst prognosis. Cox regression analysis for DFS confirmed what was observed by univariate analysis for all variables: the only independent variable in predicting DFS was pathologic lymph-node involvement.
                Our findings suggest no difference in OS, loco-regional and distant site progressions of postoperative RT alone compared to sequential postoperative RT and CT; notably, this latter regimen was associated with higher toxicity which seriously impaired the patient's compliance to CT. The low loco-regional recurrence rate (9.2%) observed in our patients undergoing postoperative RT alone compared to similarly treated patients in previously performed clinical trials (20-25%) underline the role of radical surgery (mesorectal excision) coupled with a complete postoperative RT regimen. On the other hand, the similar efficacy of these two adjuvant modalities of treatment might be conditioned by both the low compliance (59%) to the CT regimen as well as the sequential, instead of concurrent, schedule of administration of RT and CT, which may have decreased further the expected efficacy of the combined regimen.
                Copyright 2003 Wiley-Liss, Inc. nan The aim of the QUASAR trial was to determine the size and duration of any survival benefit from adjuvant chemotherapy for patients with colorectal cancer at low risk of recurrence, for whom the indication for such treatment is unclear.
                After apparently curative resections of colon or rectal cancer, 3239 patients (2963 [91%] with stage II [node negative] disease, 2291 [71%] with colon cancer, median age 63 [IQR 56-68] years) enrolled between May, 1994, and December, 2003, from 150 centres in 19 countries were randomly assigned to receive chemotherapy with fluorouracil and folinic acid (n=1622) or to observation (with chemotherapy considered on recurrence; n=1617). Chemotherapy was delivered as six 5-day courses every 4 weeks or as 30 once-weekly courses of intravenous fluorouracil (370 mg/m2) with high-dose (175 mg) L-folinic acid or low-dose (25 mg) L-folinic acid. Until 1997, levamisole (12 courses of 450 mg over 3 days repeated every 2 weeks) or placebo was added. After 1997, patients who were assigned to receive chemotherapy were given fluorouracil and low-dose folinic acid only. The primary outcome was all-cause mortality. Analyses were done by intention to treat. This trial is registered with the International Clinical Trial Registry, number ISRCTN82375386.
                At the time of analysis, 61 (3.8%) patients in the chemotherapy group and 50 (3.1%) in the observation group had missing follow-up. After a median follow-up of 5.5 (range 0-10.6) years, there were 311 deaths in the chemotherapy group and 370 in the observation group; the relative risk of death from any cause with chemotherapy versus observation alone was 0.82 (95% CI 0.70-0.95; p=0.008). There were 293 recurrences in the chemotherapy group and 359 in the observation group; the relative risk of recurrence with chemotherapy versus observation alone was 0.78 (0.67-0.91; p=0.001). Treatment efficacy did not differ significantly by tumour site, stage, sex, age, or chemotherapy schedule. Eight (0.5%) patients in the chemotherapy group and four (0.25%) in the observation group died from non-colorectal cancer causes within 30 weeks of randomisation; only one of these deaths was deemed to be possibly chemotherapy related.
                Chemotherapy with fluorouracil and folinic acid could improve survival of patients with stage II colorectal cancer, although the absolute improvements are small: assuming 5-year mortality without chemotherapy is 20%, the relative risk of death seen here translates into an absolute improvement in survival of 3.6% (95% CI 1.0-6.0). We investigated the efficacy and safety of adjuvant immunochemotherapy and adjuvant chemotherapy for colorectal cancer, using different combinations of the intracutaneous streptococcal preparation OK-432 and the oral pyrimidines 1-hexylcarbamoyl-5-fluorouracil (carmofur, HCFU) and uracil/tegafur (UFT).
                Patients with stage II, III, or IV (Dukes' B, C) colorectal cancer were enrolled and randomly assigned to one of three groups: an immunochemotherapy group (mitomycin C [MMC] + 5-fluorouracil [5-FU] + HCFU + OK-432), a chemotherapy group (MMC + 5-FU + HCFU), and a control group (surgery alone) for those with colon cancer (study 1); and an immunochemotherapy group (MMC + 5-FU + UFT + OK-432), a chemotherapy group (MMC + 5-FU + UFT), and a control group (surgery alone) for those with rectal cancer (study 2).
                A total of 760 patients with colon cancer and 669 patients with rectal cancer were entered into this randomized clinical trial (RCT). The incidence of side-effects was in the order of: immunochemotherapy group > chemotherapy group > control group in both the cohort of patients with colon cancer and the cohort with rectal cancer. In particular, the frequency of leucopenia and skin disorders was significantly higher than control groups. There were no severe adverse events such as death related to the adjuvant therapy. In both the colon cancer and rectal cancer cohorts, no significant difference in the 5-year survival rate and disease-free survival rate was noted among the three groups.
                The results of an RCT demonstrated that the combination of MMC + 5-FU + HCFU + OK-432 for colon cancer and that of MMC + 5-FU + UFT + OK-432 for rectal cancer could not prolong the survival of patients with surgically resected colorectal cancer, but that both combinations were well tolerated as adjuvant therapy. We investigated the efficacy and safety of adjuvant immunochemotherapy and adjuvant chemotherapy for colorectal cancer, using different combinations of the intracutaneous streptococcal preparation OK-432 and the oral pyrimidines 1-hexylcarbamoyl-5-fluorouracil (carmofur, HCFU) and uracil/tegafur (UFT).
The results of this meta-analysis support the use of 5-FU based postoperative adjuvant chemotherapy for patients undergoing apparently radical surgery for non-metastatic rectal carcinoma. Available data do not allow us to define whether the efficacy of this treatment is highest in one specific TNM stage. The implementation of modern anti-cancer agents in the adjuvant setting is warranted to improve the results shown by this meta-analysis. Randomized trials of adjuvant chemotherapy for patients receiving preoperative neoadjuvant therapy are also needed in order to define the role of postoperative chemotherapy in the multimodal treatment of resectable rectal cancer.