Impact of age and medical comorbidity on adjuvant treatment outcomes for stage III colon cancer: a pooled analysis of individual patient data from four randomized, controlled trials.

BACKGROUND: Adjuvant oxaliplatin plus capecitabine or leucovorin/5-fluorouracil (LV/5-FU) (XELOX/FOLFOX) is the standard of care for stage III colon cancer (CC); however, there is disagreement regarding oxaliplatin benefit in patients aged >70. In most analyses, the impact of medical comorbidity (MC) has not been assessed. Efficacy and safety of adjuvant XELOX/FOLFOX versus LV/5-FU were compared with respect to age and MC using pooled data from four randomized, controlled trials, selected for access to patient-level MC data and including commonly endorsed and utilized regimens. PATIENTS AND METHODS: Individual data from patients with stage III CC in NSABP C-08, XELOXA, X-ACT, and AVANT were pooled, excluding bevacizumab-treated patients. Patients were grouped by treatment, MC (low versus high), or age (<70 versus ≥70), and compared for disease-free survival (DFS), overall survival (OS), and adverse events (AEs). Multivariable Cox proportional hazards regression controlled for gender, T stage, and N stage. RESULTS: DFS benefits were shown for XELOX/FOLFOX versus LV/5-FU regardless of age or MC, although benefits were modestly attenuated for patients aged ≥70. Hazard ratios were 0.68 (P < 0.0001) and 0.77 (P < 0.014) for <70 and ≥70 age groups; 0.69 (P < 0.0001) and 0.59 (P < 0.0001) for Charlson Comorbidity Index ≤1 and >1 groups; and 0.70 (P < 0.0001) and 0.58 (P < 0.0001) for National Cancer Institute Combined Index ≤1 and >1 groups. OS was also significantly improved in all groups. Grade 3/4 serious AE rates were comparable across cohorts and MC scores and higher in patients aged ≥70. Oxaliplatin-relevant grade 3/4 AEs, including neuropathy, were comparable across ages and MC scores. CONCLUSIONS: Results further support consideration of XELOX or FOLFOX as standard treatment options for the adjuvant management of stage III CC in all age groups and in patients with comorbidities, consistent with those who were eligible for these clinical trials.

Survival following early-stage colon cancer: an ACCENT-based comparison of patients versus a matched international general population†.

BACKGROUND: Post-treatment survival experience of early colon cancer (CC) patients is well described in the literature, which states that cure is probable for some patients. However, comparisons of treated patients' survival versus that expected from a matched general population (MGP) are limited. PATIENTS AND METHODS: A total of 32 745 patients from 25 randomized adjuvant trials conducted from 1977 to 2012 in 41 countries were pooled. Observed long-term survival of these patients was compared with expected survival matched on sex, age, country, and year, both overall and by stage (II and III), sex, treatment [surgery, 5-fluorouracil (5-FU), 5-FU + oxaliplatin], age (<70 and 70+), enrollment year (pre/post 2000), and recurrence (yes/no). Comparisons were made at randomization and repeated conditional on survival to 1, 2, 3, and 5 years. CC and MGP equivalence was tested, and observed Kaplan-Meier survival rates compared with expected MGP rates 3 years out from each landmark. Analyses were also repeated in patients without recurrence. RESULTS: Within most cohorts, long-term survival of CC patients remained statistically worse than the MGP, though conditional survival generally improved over time. Among those surviving 5 years, stage II, oxaliplatin-treated, elderly, and recurrence-free patients achieved subsequent 3-year survival rates within 5% of the MGP, with recurrence-free patients achieving equivalence. CONCLUSIONS: Conditional on survival to 5 years, long-term survival of most CC patients on clinical trials remains modestly poorer than an MGP, but achieves MGP levels in some subgroups. These findings emphasize the need for access to quality care and improved treatment and follow-up strategies.

Toward optimized front-line therapeutic strategies in patients with metastatic colorectal cancer--an expert review from the International Congress on Anti-Cancer Treatment (ICACT) 2009.

Metastatic colorectal cancer is a particularly frequent and severe cancer. Patients die mainly from metastatic disease; however, the survival of these patients has dramatically improved with the progress in chemotherapeutic regimens as new routes of administration and introduction of more potent cytotoxic agents administered in sequential 5-FU-folinic acid-irinotecan/5-FU-folinic acid-oxaliplatine strategies. Biologic therapies have been also developed targeting two different pathways, angiogenesis and the epidermal growth factor receptor. Their combination with chemotherapy leads to improved progression-free survival and overall survival in some cases as the addition of cetuximab in wild-type K-Ras tumors. The objectives of this expert conference were to review the different options, the available prognostic or predictive factors to optimally guide the treatment.

Phase III study of bolus versus infusion fluorouracil with or without cisplatin in advanced colorectal cancer.

BACKGROUND: Phase II studies of fluorouracil (5-FU) administered by protracted intravenous infusion have suggested an improved response rate and decreased toxicity profile when compared with 5-FU given by bolus injection in patients with metastatic colorectal cancer. Additional studies have suggested further enhancement of infusion 5-FU activity when it is combined with low-dose weekly cisplatin administration. PURPOSE: This phase III study in adults with metastatic colorectal cancer was planned as a comparison of objective response rates, toxicity, and survival in patients receiving bolus versus protracted-infusion 5-FU with or without cisplatin. METHODS: Four hundred ninety-seven previously untreated patients with advanced, measurable metastatic colorectal cancer were randomly assigned to receive treatment A (bolus 5-FU at 500 mg/m2 for 5 days followed in 2 weeks by weekly bolus 5-FU at 600 mg/m2), treatment B (bolus 5-FU at 500 mg/m2 for 5 days followed in 2 weeks by weekly bolus 5-FU at 600 mg/m2, plus weekly cisplatin at 20 mg/m2), treatment C (5-FU at 300 mg/m2 per day by continuous infusion), or treatment D (5-FU at 300 mg/m2 per day by continuous infusion plus weekly cisplatin at 20 mg/m2). All drugs were administered intravenously. Enrollment in the trial occurred from August 1987 through December 1990, and follow-up was through September 1995. The Kaplan-Meier method was used to estimate overall and disease-free survival, and Cox regression models were used to assess the effects of patient characteristics on survival. All P values resulted from two-sided tests. RESULTS: Objective tumor response was observed in 28 (18%) of 153 patients receiving treatment A, in 45 (28%) of 159 patients receiving treatment C (C versus A; P = .045), and in 47 (31%) of 153 patients receiving treatment D (D versus A; P = .016). Because of excessive toxicity, treatment B was discontinued after only 12 patients had begun treatment. Median time to disease progression was 5.1 months for patients in arm A compared with 6.2 and 6.5 months for patients in arms C and D, respectively (C versus A, P = .007; D versus A, P = .017). Patterns of toxic effects differed substantially among the treatment arms. Forty-five percent of the patients receiving bolus 5-FU alone (A) experienced grade 3-4 leukopenia, with two sepsis-related deaths. Hand-foot syndrome and mucositis were the major treatment-limiting toxic effects for patients in the two treatment arms involving infusion. Despite the improvement in response rates and time to disease progression with infusion 5-FU with or without cisplatin (C and D, respectively) (P = .003), the overall survival for the three groups (A, C, and D) was similar (P = .307). This may have been due in part to a longer median survival time of 10.4 months for patients in arm A, compared with an anticipated survival of 7 months. CONCLUSION: 5-FU given as a continuous infusion produced a higher objective response rate, a modest prolongation in time to disease progression, and less life-threatening myelosuppression in patients than bolus 5-FU. Concomitant treatment with low-dose cisplatin caused added toxicity and complexity of treatment and did not provide a major clinical benefit. No statistically significant survival differences were observed among the three treatment groups.

Protracted intravenous fluorouracil infusion with radiation therapy in the management of localized pancreaticobiliary carcinoma: a phase I Eastern Cooperative Oncology Group Trial.

PURPOSE: The purpose of this study was to determine the maximum-tolerated dose (MTD) of fluorouracil (5-FU) administered as a protracted intravenous (IV) infusion with concurrent radiation in patients with pancreaticobiliary carcinoma. METHODS: Twenty-five patients with recurrent, residual, or unresectable carcinoma of the pancreas or biliary tract were treated on a phase I trial of protracted IV infusions of 5-FU, beginning at 200 mg/m2/d, concurrent with radiation therapy (59.4 Gy in 33 fractions over 6 to 7 weeks). Chemotherapy began on the first day of radiation and continued through the entire course of treatment. After each cohort of five patients had been treated and observed, the daily dose was escalated in 25-mg/m2 increments until dose-limiting toxicity was encountered. An additional cohort of five patients was treated at the MTD. Clinical examination and computed tomography (CT) were used to evaluate response and patterns of progression. RESULTS: The MTD of 5-FU was 250 mg/m2/d. The dose-limiting toxicity was oral mucositis. The median survival duration of all patients treated was 11.9 months and the 2-year survival rate was 19%. Eleven of 25 patients remain free of local progression and four patients are without evidence of progression at 18+, 18+, 34+, and 44+ months following treatment. CONCLUSION: Concurrent radiation with protracted 5-FU infusion at 250 mg/m2/d is well tolerated and shows evidence of activity against tumors of the pancreas and biliary system.

Hepatic toxicity associated with fluorouracil plus levamisole adjuvant therapy.

PURPOSE: To determine the frequency and nature of hepatic toxicity associated with fluorouracil (5-FU) plus levamisole adjuvant therapy. PATIENTS AND METHODS: All patients had resection of stage II or stage III colon cancer and were randomized to receive observation only, levamisole alone, or 5-FU plus levamisole. Serial liver function studies were documented in 1,025 patients who did not develop recurrence during the year of therapy. RESULTS: One hundred forty-nine (39.6%) of 376 patients treated with 5-FU plus levamisole showed laboratory abnormalities consistent with hepatic toxicity, compared with 16.3% of 251 patients treated with levamisole alone and 16.1% of 398 untreated controls. Most common was elevation of alkaline phosphatase, frequently accompanied by elevations of transaminase or serum bilirubin. Characteristically, these changes were mild, not associated with symptoms, and resolved when therapy was stopped. In some instances, they were associated with elevated carcinoembryonic antigen (CEA) tests or with fatty liver seen on computed tomographic (CT) scan or liver biopsy. CONCLUSION: Mild and reversible hepatotoxicity is a common consequence of 5-FU plus levamisole adjuvant therapy, but this is only rarely symptomatic. However, the oncologist should be alert to this phenomenon, since the associated laboratory and imaging findings may simulate those associated with hepatic metastasis.

Colon cancer survival is associated with increasing number of lymph nodes analyzed: a secondary survey of intergroup trial INT-0089.

PURPOSE: To determine the relationship, in patients with adenocarcinoma of the colon, between survival and the number of lymph nodes analyzed from surgical specimens. PATIENTS AND METHODS: Intergroup Trial INT-0089 is a mature trial of adjuvant chemotherapy for high-risk patients with stage II and stage III colon cancer. We performed a secondary analysis of this group with overall survival (OS) as the main end point. Cause-specific survival (CSS) and disease-free survival were secondary end points. Rates for these outcome measures were estimated using Kaplan-Meier methodology. Log-rank test was used to compare overall curves, and Cox proportional hazards regression was used to multivariately assess predictors of outcome. RESULTS: The median number of lymph nodes removed at colectomy was 11 (range, one to 87). Of the 3411 assessable patients, 648 had no evidence of lymph node metastasis. Multivariate analyses were performed on the node-positive and node-negative groups separately to ascertain the effect of lymph node removal. Survival decreased with increasing number of lymph node involvement (P =.0001 for all three survival end points). After controlling for the number of nodes involved, survival increased as more nodes were analyzed (P =.0001 for all three end points). Even when no nodes were involved, OS and CSS improved as more lymph nodes were analyzed (P =.0005 and P =.007, respectively). CONCLUSION: The number of lymph nodes analyzed for staging colon cancers is, itself, a prognostic variable on outcome. The impact of this variable is such that it may be an important variable to include in evaluating future trials.

Phase I clinical and pharmacogenetic trial of irinotecan and raltitrexed administered every 21 days to patients with cancer.

PURPOSE: Irinotecan and raltitrexed display schedule-dependent synergy in vitro, which supports the clinical investigation of the combination. Functional polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) gene result in intracellular redistribution of folate derivatives, which may affect raltitrexed-associated cytotoxicity. PATIENTS AND METHODS: Patients with a range of solid cancers and good performance status received irinotecan as a 90-minute infusion on day 1 and raltitrexed as a 15-minute infusion on day 2, repeated every 21 days. Samples were collected for MTHFR C677T genotyping and fasting plasma homocysteine during the first cycle. RESULTS: Thirty-nine assessable patients received 127 cycles of therapy. Irinotecan doses ranged from 100 to 350 mg/m(2), and raltitrexed, 1.0 to 4.0 mg/m(2). Raltitrexed doses of more than 3.0 mg/m(2) were not tolerated and were associated with dose-limiting asthenia, diarrhea, and AST/ALT elevation. Irinotecan/raltitrexed doses of 350/3.0 mg/m(2) were well-tolerated; principal toxicities included neutropenia, diarrhea, and fatigue. Two partial responses were observed in patients with pretreated gastroesophageal cancers. Homozygotes with the MTHFR 677 TT polymorphism incurred significantly less raltitrexed-associated toxicity than those with either wild-type or heterozygous genotypes (P = .05). No significant differences were noted in plasma homocysteine values between the genotypic subtypes, and plasma homocysteine levels did not predict the risk of toxicity. CONCLUSION: Irinotecan and raltitrexed doses of 350 and 3.0 mg/m(2) are recommended for further study on a day 1, 2 schedule every 21 days. Efficacy results suggest that trials in upper and lower gastrointestinal malignancies are warranted. MTHFR C677T genotypes may be predictive of clinical raltitrexed toxicity.

Controlled trial of fluorouracil and low-dose leucovorin given for 6 months as postoperative adjuvant therapy for colon cancer.

PURPOSE: The goal of this study was to determine the efficacy of intensive-course fluorouracil (5FU) plus low-dose leucovorin given for 6 months following potentially curative resection of colon cancer. PATIENTS AND METHODS: Three hundred seventeen patients with high-risk stage II or stage III colon cancer were randomly assigned 3 to 4 weeks following surgery to receive either (1) chemotherapy with six cycles of 5FU (425 mg/m2) plus leucovorin (20 mg/m2) by rapid intravenous injection daily for 5 consecutive days every 4 to 5 weeks, or (2) observation. RESULTS: The median follow-up duration is 72 months for patients still alive. Patients who received postoperative 5FU plus leucovorin experienced significant improvement in time to relapse (P < .01) and survival (P = .02) compared with control patients treated with surgery alone. Stomatitis, diarrhea, and leukopenia were the predominant chemotherapy toxicities. There were no treatment-related deaths. CONCLUSION: These results indicate that intensive-course 5FU plus low-dose leucovorin is effective in preventing tumor relapse and improving survival in patients with high-risk colon cancer. These benefits were seen with only six cycles of treatment, using low-dose leucovorin in combination with 5FU on a schedule convenient for outpatient administration.

Adjuvant active specific immunotherapy for stage II and III colon cancer with an autologous tumor cell vaccine: Eastern Cooperative Oncology Group Study E5283.

PURPOSE: A randomized phase III clinical trial of adjuvant active specific immunotherapy (ASI) with an autologous tumor cell-bacillus Calmette-Guérin (BCG) vaccine was conducted to determine whether surgical resection plus ASI was more beneficial than resection alone in stage II and III colon cancer patients. PATIENTS AND METHODS: Patients (n = 412) with colon cancer (297 with stage II disease, 115 with stage III disease) were randomly allocated to an observation arm or to a treatment arm in which they received three weekly intradermal vaccine injections of 10(7) irradiated autologous tumor cells beginning approximately 4 weeks after surgery. The first two weekly injections also contained 10(7) BCG organisms. Patients were observed for determination of time to recurrence and disease-free and overall survival. RESULTS: This was a negative study in that after a 7.6-year median follow-up period, there were no statistically significant differences in clinical outcomes between the treatment arms. However, there were disease-free survival (P =.078) and overall survival (P =.12) trends in favor of ASI when treatment compliance was evaluated, ie, patients who received the intended treatment had a delayed cutaneous hypersensitivity (DCH) response to the third vaccination (induration >/=5 mm). Also, the magnitude of the DCH response correlated with improved prognosis. The 5-year survival proportion was 84.6% for those with indurations greater than 10 mm, compared with 45.0% for those with indurations less than 5 mm. CONCLUSIONS: When all randomized patients were evaluated, no significant clinical benefit was seen with ASI in surgically resected colon cancer patients with stage II or III colon cancer. However, there was an indication that treatment compliance with effective immunization results in disease-free and overall survival benefits.

Intergroup study of fluorouracil plus levamisole as adjuvant therapy for stage II/Dukes' B2 colon cancer.

PURPOSE: To determine the effectiveness of fluorouracil plus levamisole administered postoperatively to patients with resected stage II (Dukes' B2) colon cancer. PATIENTS AND METHODS: This randomized controlled clinical trial (INT-0035) was performed by National Cancer Institute-sponsored cancer clinical trials cooperative groups. Patients were assigned to observation only or to fluorouracil (450 mg/m2 intravenously [IV] daily for 5 days and, beginning at 28 days, weekly for 48 weeks) plus levamisole (50 mg orally three times daily for 3 days repeated every 2 weeks for 1 year). Cancer recurrence, survival, and treatment side effects were assessed. RESULTS: Three hundred eighteen eligible patients were analyzed with a median follow-up time of 7 years. Fluorouracil plus levamisole reduced the recurrence rate by 31%, although this trend was not statistically significant (P = .10). A total of 87 patients died: 43 on observation and 44 on fluorouracil plus levamisole. Disparity between effects on recurrence rate and overall survival is partially explained by a higher rate of non-colon cancer-related deaths on fluorouracil plus levamisole (15 v seven) and by the effects of salvage surgery with curative intent. Of seven patients with recurrence who were rendered disease-free by salvage surgery, six were on the observation arm. As was observed in patients treated with fluorouracil plus levamisole for stage III disease, toxicity was acceptable and compliance was excellent. CONCLUSION: Fluorouracil plus levamisole is tolerable and accepted as standard surgical adjuvant therapy for patients with stage III colon cancer, but the data from this study in stage II patients suggest a decreased relapse rate without a significant improvement in survival.

Fluorouracil modulation in colorectal cancer: lack of improvement with N -phosphonoacetyl- l -aspartic acid or oral leucovorin or interferon, but enhanced therapeutic index with weekly 24-hour infusion schedule--an Eastern Cooperative Oncology Group/Cancer and Leukemia Group B Study.

PURPOSE: To investigate mechanism-directed regimens in maximizing the efficacy of fluorouracil (5-FU) in advanced colorected cancer. PATIENTS AND METHODS: Based on promising phase II data, a randomized comparison of various methods for the biochemical modulation of 5-FU was undertaken in patients with advanced colorectal cancer. The control group received single-agent 5-FU as a 24-hour infusion weekly. Patients (N = 1,120) with no prior chemotherapy for metastatic disease were randomized to one of the following arms: arm A, 5-FU 2,600 mg/m2 by 24-hour infusion, weekly; arm B, N-phosphonoacetyl-l-aspartic acid 250 mg/m2 day l, 5-FU 2,600 mg/m2 by 24-hour infusion day 2, weekly; arm C, 5-FU 600 mg/m2 with oral leucovorin (LV) 125 mg/m2 hourly for the preceding 4 hours, weekly; arm D, 5-FU 600 mg/m2 with intravenous (IV) LV 600 mg/m2, weekly; arm E, 5-FU 750 mg/m2/d IV by continuous infusion for 5 days, then 750 mg/m2 weekly, and recombinant interferon alfa-2a 9 million units subcutaneously three times weekly. Median follow-up was 4.8 years. RESULTS: Of the 1,098 assessable patients, 57% had measurable disease. The toxicity of all the regimens was tolerable. Grade 4 or worse toxicity occurred in 11%, 11%, 30%, 24%, and 22% on each arm, respectively; diarrhea was the most common adverse effect. These toxicity patterns favored significantly (P <.001) the 24-hour infusion arms. Median survival (months) by arm was A, 14.8; B, 11.9; C, 13.5; D, 13.6; and E, 15.2. These survival durations did not differ significantly. CONCLUSION: We conclude that a weekly infusion regimen of 5-FU is significantly less toxic than and as effective as 5-FU bolus regimens modulated by either LV or interferon in patients with metastatic colorectal cancer.

Radiation therapy for rectosigmoid and rectal cancer: results of the 1992-1994 Patterns of Care process survey.

PURPOSE: To determine the US national practice standards for patients with adenocarcinoma of the rectum treated in radiation oncology facilities. MATERIALS AND METHODS: A national survey of 57 institutions identified 507 eligible patients who received radiation therapy as a component of their treatment for rectal cancer. A stratified two-stage cluster sampling with simple random sampling at each stage for each stratum was used and on-site surveys were performed. RESULTS: Of the 507 patients, 378 (75%) received postoperative therapy, 110 (22%) received preoperative therapy, 17 (2%) received both preoperative and postoperative therapy, and less than 0.5% received intraoperative radiation alone. To more accurately assess the utilization of modern radiation techniques as well as recommendations of the National Cancer Institute (NCI)-sponsored, randomized, postoperative, adjuvant combined modality therapy rectal cancer trials into current practice, the analysis was limited to the 243 (48%) patients with tumor, node, and metastasis staging system classification T3 and/or N1-2M0 disease who underwent conventional surgery with negative margins. Although only 7% were treated on a clinical trial, 90% received chemotherapy for a median of 21 weeks. Most were treated with modern radiation treatment techniques. In contrast, techniques to identify and help exclude the small bowel from the radiation field were not routinely used. CONCLUSION: Despite the fact that only 7% of patients with T3 and/or N1-2M0 disease were treated on a clinical trial, such trials appear to have resulted in a positive influence on the standard of practice within the oncology community. Although there are still some deficiencies, the majority of these patients received combined modality therapy and were treated with modern radiation therapy techniques.

An overview of adjuvant therapy for colorectal cancer.

Adjuvant therapy of colorectal cancer is one of the most active areas of clinical oncology research. Although the data for the benefits from early trials of adjuvant therapy were inconclusive, these trials suffered from inadequate sample sizes, poor staging, potentially suboptimal treatment regimens and ill-defined prognostic subgroups. More recently, larger trials of higher scientific quality have demonstrated that regimens of fluorouracil plus levamisole in stage III colon cancer and fluorouracil with postoperative radiation in stages II and III rectal cancer can reduce mortality. Such regimens have now become standard practice in settings in which treatment is believed to be both efficacious and tolerable, and when the overall impact of therapy is considered to be clinically relevant. More recent advances in adjuvant treatment of colorectal cancer further support the role of fluorouracil-based regimens. Peri-operative portal vein infusions of fluorouracil demonstrate improved relapse-free and overall survival, and infusional fluorouracil administered with radiation for rectal primaries appears superior to less intensive bolus fluorouracil regimens. Completed trials of fluorouracil plus leucovorin combinations are awaiting maturation, with expectations for superior adjuvant activity based on demonstrated improved response rates for biochemically modulated fluorouracil in advanced metastatic colorectal cancer. New systemic agents are also entering large-scale adjuvant trials, including monoclonal antibody 17-1a, given alone and in conjunction with standard fluorouracil regimens. Additional cytotoxic drugs, including CPT-11 and Tomudex, offer new opportunities for alternative adjuvant regimens for the large, heterogeneous population of patients with resected colorectal cancer.

Phase I trial of UFT/leucovorin and irinotecan in patients with advanced cancer.

UFT (BMS-200604, Uftoral) is an oral fluoropyrimidine that combines uracil and the 5-fluorouracil (5-FU) prodrug, ftorafur, in a 4:1 molar ratio with single-agent activity in breast and gastrointestinal cancers. In vitro studies have shown that irinotecan downregulates thymidylate synthase (TS) expression in tumour cells, leading to synergy between irinotecan and 5-FU that is maximal when irinotecan is given 24 h prior to 5-FU. Given this observed synergy and the confirmatory clinical activity of combination therapy with 5-FU, leucovorin (LV) and irinotecan, we performed a phase I trial to determine the maximum tolerated doses (MTD) of UFT, LV, and irinotecan. Treatment consisted of irinotecan administered as a 90-min intravenous (i.v.) infusion on day 1 followed by twice daily oral UFT/LV on days 2-15, repeated every 21 days. Initial doses were irinotecan 200 mg/m(2) and UFT 200 mg/m(2)/day, with LV dose fixed at 60 mg/day. 31 patients received a total of 130 cycles of UFT/LV and irinotecan. 3 of 9 patients experienced grade 3/4 diarrhoea at the highest dose level of irinotecan 310 mg/m(2) and UFT 300 mg/m(2)/day. Other toxicities included neutropenia, anaemia, alopecia, nausea/vomiting and fatigue. Further dose escalation was not pursued since this level of toxicity was appropriate for future phase II study. One patient with colorectal cancer experienced a partial response and 9 patients with non-small cell lung, colorectal and gastro-oesophageal junction carcinomas had disease stabilisation lasting 4-26 (median 6) cycles. Methylenetetrahydrofolate reductase (MTHFR) C677T genotype was analysed in peripheral mononuclear cells (PMNs) obtained from 24 patients. 2 patients had the homozygous TT polymorphism and 1 of them had grade 3 diarrhoea at the first dose level. Irinotecan on day 1 followed by a 14-day course of oral UFT/LV beginning on day 2 is well tolerated, and suitable for testing in several tumour types. Doses recommended for further study on this schedule are irinotecan 310 mg/m(2) and UFT 300 mg/m(2)/day, with LV 60 mg/day.

Trimetrexate: experience with solid tumors.

Trimetrexate (TMTX), a potent inhibitor of the enzyme dihydrofolate reductase, is biochemically and metabolically similar to methotrexate (MTX). Fundamental differences between TMTX and MTX, however, mandate investigation of TMTX in both MTX-sensitive and MTX-resistant tumors. In a number of phase II clinical trials, the antitumor activity of single-agent TMTX has been variable, in part because of the heterogeneity of doses and schedules used and in part because of diverse patient populations. Single-agent activity has been documented in some commonly occurring tumors, including breast, non-small cell lung, and head and neck cancers. Other tumors with sensitivity to single-agent TMTX include transitional cell carcinomas of the urothelium, prostate cancer, and gastric carcinoma. In a small series of children with renal cell carcinoma, significant clinical activity was suggested. The single-agent activity of TMTX, coupled with the finding that TMTX may act as a biochemical modulator of 5-fluorouracil/leucovorin, suggests that the addition of TMTX to 5-fluorouracil/leucovorin should be investigated further. The possibility that TMTX may both exhibit single-agent activity and modulate the effectiveness of other agents makes combination therapy attractive.

Update of clinical trials with edrecolomab: a monoclonal antibody therapy for colorectal cancer.

Edrecolomab is a murine IgG2a monoclonal antibody that recognizes the tumor-associated antigen Ep-CAM. Its antitumor effects are mediated through antibody-dependent cellular cytotoxicity, complement-mediated cytolysis, and the induction of an anti-idiotypic network. An initial study of 189 patients with resected stage III colorectal cancer showed that edrecolomab reduced the relative risk of mortality by 32% compared with observation alone (P < .01). Edrecolomab has now been investigated in two large phase III studies of patients with stage III colon cancer, either as a single agent or in combination with 5-FU-based chemotherapy. Preliminary safety data have shown that edrecolomab is well tolerated when used as monotherapy and adds little to chemotherapy-related side effects when used in combination. Edrecolomab is also being studied as monotherapy following resection of stage II colon cancer, and in combination with chemotherapy in patients with resected stage II or III rectal cancer. In conclusion, edrecolomab is a novel biological therapy for the adjuvant treatment of colorectal cancer. Completed and ongoing trials may support its use as monotherapy in stage II colon cancer or in combination with chemotherapy in stage III colon cancer and stage II/III rectal cancer.

Chemotherapy in gastrointestinal malignancies.

The frequency of gastrointestinal (GI) cancers mandates innovative and individualized therapies. Chemotherapy used as sole treatment for these diverse malignancies has not been generally successful in providing palliation or improving patient survival. Radiotherapy has been more successful at controlling local manifestations of disease, but the high incidence of systemic metastases in most malignancies limits the impact of this modality on curability. Combinations of radiotherapy and chemotherapy may prove to be more valuable than single modality treatment in improving local control of tumors, decreasing systemic disease, and improving patient tolerance to treatment. A model for this approach is the current management of anal cancer, in which combined modality therapy has largely supplanted primary surgery. Data from trials in other primary tumor sites strongly suggest further exploration of combined treatments--surgical, radiotherapeutic, and chemotherapeutic--in GI malignancies. Nearly 25% of all malignancies diagnosed in the United States each year involve the GI tract; thus, there is a powerful imperative for the development of new therapeutic strategies in these diseases. Any discussion of the role of chemotherapy in GI cancers must necessarily be broad, because assessment must include diseases with highly variable surgical curability, histologies, and sensitivities to chemotherapeutic agents. In addition, whereas it has been quite easy to perform standard phase II trials in colorectal cancer, other disease sites, such as the esophagus, the pancreas, and the biliary tract, have been much less extensively studied. In spite of these limitations, there is a wealth of data in the literature concerning the use of chemotherapy in GI malignancies. This article, while not exhaustive, describes the current status of chemotherapy for these diverse diseases, with emphasis on the role of mitomycin C.

Progestational agents in advanced breast cancer: an overview.

Progestational agents, such as megestrol acetate and medroxyprogesterone acetate, are effective hormonal treatments for metastatic breast cancer in postmenopausal women. Clinical trials of these agents have demonstrated that 30% to 60% of patients will experience objective tumor response, depending on pretreatment prognostic variables. Although optimal doses and schedules have not been fully defined, current studies are investigating the therapeutic effectiveness of high-dose progestins. Toxicity of these drugs is mild and generally limited to weight gain related to their anabolic activity. Progestins are active second-line agents for metastatic breast cancer in postmenopausal women. In selected patients, they appear to be equivalent to tamoxifen as first-line therapy for metastatic disease. As more patients are exposed to prolonged adjuvant tamoxifen therapy, the role of progestins as first-line hormonal therapy at the time of relapse is likely to expand.

Adjuvant therapy of colon cancer.

Colon cancer is an important cause of cancer-related mortality. A series of clinical trials of adjuvant systemic therapy have been performed in attempt to establish means to improve outcome in this disease. By the early 1990s, a role for 5-fluorouracil (5-FU)-based chemotherapy in stage III colon cancer had been firmly established. The precise role for chemotherapy in stage II disease remains under investigation. Progress continues toward optimizing the schedule and duration of systemic therapy, allowing for maximal efficacy with a minimum of toxicity. It appears that approximately 6 months of 5-FU and leucovorin are as effective as more prolonged regimens. Levamisole does not appear to add to the benefit of 5-FU and leucovorin. Several newer agents such as the oral fluorinated pyrimidines, irinotecan (CPT-11) and oxaliplatin have demonstrated activity in metastatic colon cancer and hold promise as potentially effective drugs to be tested in the adjuvant setting.