Effective surgical adjuvant therapy for high-risk rectal carcinoma. Postoperative adjuvant chemotherapy or radiation therapy for rectal cancer: results from NSABP protocol R-01. Adjuvant preoperative radiotherapy for locally advanced rectal carcinoma. Results of a prospective, randomized trial. [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]. Randomized study of systemic chemotherapy following complete excision of nonosseous sarcomas. 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. Randomized trial of the efficacy of adjuvant chemotherapy for colon cancer with combination therapy incorporating the oral pyrimidine 1-hexylcarbamoyl-5-fluorouracil. An individual patient data meta-analysis of adjuvant therapy with uracil-tegafur (UFT) in patients with curatively resected rectal cancer. [Prospective controlled study on the usefulness of Carmofur as a postoperative adjuvant chemotherapy for colorectal cancer].
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. 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, randomized clinical trial was conducted by the Northwest Rectal Cancer Group to study the effects of preoperative radiotherapy given one week before surgery in locally advanced (tethered or fixed) rectal carcinoma.
                A total of 284 patients were entered into the trial between 1982 and 1986; 141 were allocated to receive surgical treatment alone, and 143 were allocated to receive preoperative radiotherapy. A 10 x 10 x 10 cm volume in the posterior pelvis, centered on the tumor, was irradiated at a dose of 20 Gy, divided into four daily fractions of 5 Gy each.
                No differences were observed in any of the clinicopathologic variables in the two arms of the trial; there were no striking down-staging effects in the irradiated tumors. After a minimum follow-up period of 96 months, the overall and cancer-related mortality rates were similar in both arms of the study (P = 0.21 and P = 0.09, respectively). There was a highly significant reduction in local recurrences in the irradiated group (12.8 percent x-ray therapy vs. 36.5 percent surgery; P = 0.0001). The majority of local recurrences after preoperative radiotherapy occurred inside the radiotherapy field (10 cases; 7 percent), with only six cases (5 percent) outside the field. No significant difference was observed in the rates of distant metastasis between the two treatment groups (P = 0.73).
                Although there is no statistically significant survival benefit in the whole series, there is a survival benefit for the subset of patients considered by the surgeon to have undergone a curative operation. We recommend that this form of adjuvant therapy should be offered to all patients with locally advanced rectal cancer who are to undergo radical surgery. 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. Between June 1975 and April 1981, 61 of the 177 eligible patients whose nonosseous sarcomas of extremity or trunk origin had been completely excised primarily or after local recurrences agreed to participate in a randomized study of adjuvant chemotherapy. Dermatofibrosarcoma, lymphomas, myeloma, Kaposi's sarcoma, and embryonal rhabdomyosarcoma were excluded as were patients with significant second primary cancers and those who received either preoperative or postoperative radiation therapy. After stratification by anatomic status of disease, site of origin, and histologic grade, a random one half of the 61 participants began alternating courses of vincristine/cyclophosphamide/dactinomycin, and vincristine/doxorubicin/dacarbazine at six-week intervals for one year. The control group was evaluated at six-week intervals without adjuvant chemotherapy, but these patients were offered this chemotherapy later if they had progressive disease excised. Although 30% of the 61 patients experienced local recurrence of disease within the first five years after randomization, and only 54% were continuously disease free for five or more years, 82% were surviving at five years (Kaplan-Meier calculations) with a median follow-up of 64.3 months. Partial suppression of distant metastasis by adjuvant chemotherapy was apparent in the overall study, in the extremity tumor category, and in the subgroup of patients who had received limb-sparing surgery; however, no survival advantage for chemotherapy-treated patients was demonstrated. The 30 adjuvant chemotherapy-treated patients received a total of three thoracotomies as compared with 17 salvage thoracotomies for the 31 control patients; however, salvage surgery for local recurrences has been similar in the two groups. Recent improvement in the survival of patients with soft-tissue sarcomas is not necessarily a result of adjuvant chemotherapy or radiation 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).
                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 purpose of the present trial was to clarify the efficacy of postoperative adjuvant chemotherapy including an oral fluoropyrimidine anticancer drug, the 1-hexylcarbamoyl-5-fluorouracil (HCFU), for the treatment of colon cancer.
                Patients with clinical stage Dukes' B and C colon cancer, who had been treated surgically, were assigned to a chemotherapy group treated with mitomycin C, 5-fluorouracil (5-FU), and HCFU and to a control group that received no postoperative adjuvant chemotherapy.
                Of the 1,001 patients registered for the study, 17 (1.7%) were ineligible. The incidence of toxicity was significantly higher in the chemotherapy group than in the control group. However, there were few severe side effects and no deaths related to the treatment. Overall survival showed no significant difference between the groups. The disease-free survival or the recurrence-free intervals was significantly higher in the chemotherapy group than in the control group. The incidence of hepatic recurrence was significantly (P=0.003) lower in the chemotherapy group than in the control group.
                The results of this study demonstrated the efficacy of adjuvant chemotherapy for colon cancer, i.e., combined chemotherapy that included the 5-FU oral anticancer drug HCFU. 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. 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.
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.