Advances in the treatment of metastatic colorectal cancer

The overall 5-year survival rate for patients with metastatic colorectal cancer (CRC) is less than 10%. Median survival with 5-fluorouracil (5-FU)/leucovorin (LV) therapy is approximately 12 months. Recent additions to the chemotherapy armamentarium for this disease have begun to prolong median survival times. In trials in which patients are exposed to all three approved chemotherapy agents, oxaliplatin, irinotecan, and 5-FU/LV, or capecitabine during the course of their disease, median survival has reached 20 months. The addition of oxaliplatin and irinotecan to 5-FU/LV regimens has also led to the maintenance of quality of life for longer intervals than were traditionally observed with 5-FU/LV alone. Current standard first-line regimens for metastatic CRC are FOLFOX (infusional 5-FU/LV with oxaliplatin) and FOLFIRI (infusional 5-FU/LV with irinotecan). The addition of bevacizumab to a two-drug regimen (irinotecan with 5-FU/LV) prolongs median survival to 20 months, with a modest amount of additional toxicity. Improvements in this median survival have not yet been realized with modifications to the current standard regimens; however, the oral agent capecitabine appears to be a reasonable substitute for infusional 5-FU/LV in combination regimens or as a single agent, with the advantage of reducing the inconvenience of the long infusion time. Ongoing investigations will identify a place for capecitabine, epidermal growth factor inhibitors, and new cytotoxics in the treatment of metastatic CRC.     

New systemic frontline treatment for metastatic colorectal carcinoma

Options for first-line chemotherapy in patients with metastatic colorectal carcinoma have broadened considerably with the introduction of irinotecan and oxaliplatin. Furthermore, the oral fluoropyrimidine capecitabine has demonstrated efficacy in Phase III trials and recently was approved for first-line treatment in Europe and the United States. Capecitabine yielded similar median times to disease progression and median survival rates compared with bolus 5-fluorouracil (5-FU)/leucovorin (LV) (Mayo Clinic/North Central Cancer Treatment Group regimen), with superior and similar response rates, respectively. However, its role as a first-line, single-agent substitute for intermittent infusional 5-FU/LV remains to be defined. The addition of irinotecan or oxaliplatin to 5-FU/LV resulted in improved response rates and progression-free survival in large, randomized trials; moreover, irinotecan-containing regimens resulted in improved overall survival. Prevalent regimens of irinotecan/5-FU/LV and oxaliplatin/5-FU/LV have been compared in two randomized Phase III trials. One study demonstrated the statistical superiority of oxaliplatin/infusional 5-FU/LV over irinotecan/bolus 5-FU/LV in terms of response, time to disease progression, and median survival; however, those advantages may have been attributable to infusional administration or to major differences in second-line therapy. A randomized Phase III study comparing irinotecan and oxaliplatin in combination with the same infusional 5-FU/LV regimens and crossover in case of disease progression showed equivalent efficacy for both schedules in the first-line setting, but the irinotecan combination proved beneficial in terms of safety. New molecular targeted agents, such as angiogenesis-modulating compounds (e.g., bevacizumab) and epidermal growth factor receptor inhibitors (e.g., cetuximab), are under clinical investigation. This review updates current systemic frontline treatments and future perspectives for patients with advanced colorectal carcinoma.     

IFL

An IFL regimen combining irinotecan, a bolus administration of 5-fluorouracil (5-FU) and leucovorin (LV) was associated with a significantly better response rate, progression-free survival and median overall survival, compared to 5-FU/LV against metastatic colorectal cancer. Despite a favorable initial report, randomized trials have suggested that triple therapy may be more toxic (severe neutropenia, diarrhea), leading to unacceptably high rates of early treatment-related mortality. On the other hand,a survival benefit for the oxaliplatin-containing regimen (FOLFOX 4) compared to bolus IFL, has been shown from INT trial 9741, and a European trial (V 308) suggests similar efficacy for combinations of irinotecan or oxaliplatin with short-term infusional 5-FU/LV (FOLFIRI or FOLFOX 6). Overall, FOLFIRI or FOLFOX regimen is now a standard option for first-line treatment of metastatic CRC.     

The future development of bevacizumab in colorectal cancer

Bevacizumab (Avastin), the first approved therapy designed to inhibit tumor angiogenesis, has significant clinical benefits in the management of colorectal cancer (CRC). When bevacizumab is added to IFL (5-fluorouracil [5-FU]/leucovorin [LV]/irinotecan [Camptosar)]) as first-line therapy for metastatic CRC, significant overall and progression-free survival benefits are obtained. Similar survival benefits may be achieved when bevacizumab is added to 5-FU/LV alone. In addition, additive and synergistic effects with a range of chemotherapeutic agents illustrate that bevacizumab has considerable potential in combination with existing therapeutic options. Clinical data indicate that bevacizumab is the only agent in addition to chemotherapy that has demonstrated survival benefit in the first- and second-line settings. In addition, bevacizumab is expected to produce clinical benefit in the adjuvant setting: inhibition of vascular endothelial growth factor should prevent the angiogenic switch in micrometastases, which is a key factor in malignancy. The clinical program is examining the activity of bevacizumab in combination with the likely future standard of care in both the metastatic and adjuvant treatment settings. Phase III trials (NO16966C, CONcePT and TREE-2) are studying the benefit of combining bevacizumab with oxaliplatin (Eloxatin)-based regimens. Similarly, in the adjuvant setting, phase III trials are assessing the efficacy and tolerability of bevacizumab in combination with oxaliplatin-based chemotherapy (AVANT, NSABP C-08).     

Bevacizumab in combination with fluorouracil and leucovorin: an active regimen for first-line metastatic colorectal cancer.

PURPOSE: In a phase III trial, combining bevacizumab (BV)--a recombinant, humanized, monoclonal antibody targeting vascular endothelial growth factor--with irinotecan, bolus fluorouracil (FU), and leucovorin (LV; IFL) increased survival compared with IFL alone in first-line treatment of patients with metastatic colorectal cancer (CRC). Results for the parent study of IFL/BV versus IFL/placebo are reported elsewhere. Here, we describe efficacy and safety results for the third patient cohort in this trial, who received BV combined with FU/LV, and compare them with results for concurrently enrolled patients who received IFL. METHODS: Patients (N = 923) were randomly assigned to receive IFL/placebo (control), IFL/BV, or FU/LV/BV. Bevacizumab (Avastin; Genentech Inc, South San Francisco, CA) 5 mg/kg was administered intravenously every 2 weeks. Before an interim analysis confirmed acceptable safety for IFL/BV, 313 patients were concurrently randomly assigned to these three arms; after this analysis, the FU/LV/BV arm was discontinued. RESULTS: Median overall survivals were 18.3 and 15.1 months with FU/LV/BV (n = 110) and IFL/placebo (n = 100), respectively. Median progression-free survivals were 8.8 and 6.8 months, respectively. Overall response rates were 40.0% and 37.0%, and median response durations were 8.5 and 7.2 months, respectively. Adverse events consistent with those expected from FU/leucovorin- or IFL-based regimens were seen, as were modest increases in hypertension and bleeding in the bevacizumab arm, which were generally easily managed. CONCLUSION: The FU/LV/BV regimen seems as effective as IFL and has an acceptable safety profile. FU/LV/BV is an active alternative treatment regimen for patients with previously untreated metastatic CRC.     

Mortality associated with daily bolus 5-fluorouracil/leucovorin administered in combination with either irinotecan or oxaliplatin: results from Intergroup Trial N9741

BACKGROUND: Intergroup Trial N9741 evaluated 5-fluorouracil (5-FU)/leucovorin (LV) administered in conjunction with either irinotecan or oxaliplatin in the first-line treatment of advanced colorectal carcinoma (CRC). The current report describes two treatment arms that were withdrawn from the protocol due to unexpected treatment-related toxicities and a high mortality rate. The complications observed in these arms highlight the importance of aggressive and immediate supportive care in the management of digestive toxicity. METHODS: In Trial N9741, patients were randomly assigned to receive one of the following six regimens: 1) irinotecan plus bolus 5-FU/LV (Arm A); 2) sequential irinotecan plus bolus 5-FU/LV (Arm B); 3) bolus 5-FU/LV only (Mayo Clinic regimen; Arm D); 4) oxaliplatin plus bolus 5-FU/LV (Arm E); 5) oxaliplatin plus infusional 5-FU/LV (Arm F); or 6) oxaliplatin plus irinotecan (Arm G). In the current study, the authors investigated treatment-related toxicity in patients who received either of the two combination regimens containing daily bolus 5-FU (i.e., patients in Arm B or Arm E). RESULTS: Sixty-one and 47 patients were enrolled in Arm B and Arm E, respectively. Diarrhea and neutropenia were the most common toxicities in both groups. Five patients in Arm B (8.2%) and 4 patients in Arm E (8.5%) died within 60 days of study entry. All fatal toxicities occurred within 15 days of treatment administration, and all deaths were associated with the simultaneous occurrence of multiple symptoms, which were dominated by Grade > or = 3 diarrhea. CONCLUSIONS: Combination regimens containing daily bolus 5-FU/LV and oxaliplatin or irinotecan can be associated with severe gastrointestinal toxicity and high mortality rates. Therefore, the authors recommend the use of more tolerable infusional 5-FU-based regimens in the treatment of metastatic CRC.     

晚期结直肠癌内科治疗进展

晚期转移性结直肠癌的5年生存率低于10％。5-FU／LV方案治疗的中位生存期大约12个月。最近化疗方案的更新延长了患者的中位生存期。研究发现奥沙利铂、伊立替康联合5-FU／LV或者卡培他滨等化疗方案使中位生存期延长到20个月。奥沙利铂，伊立替康联合5-FU／LV比传统的单药5-FU／LV使生活质量改善时间延长。目前转移性结直肠癌标准的一线治疗方案为FOLFOX和FOLFIRI。正在进行的研究关注新的分子靶向药物（molecular targeted therapy）联合化疗治疗转移性结直肠癌，且部分试验取得了较好的疗效。本文将对5-FU、新一代化疗药物以及分子靶向药物在转移性结肠癌治疗的演进及新进展作一综述。     

Oxaliplatin plus oral fluoropyrimidines in colorectal cancer

The medical treatment of colorectal cancer (CRC) has rapidly evolved in recent years with the introduction of novel cytotoxic drugs into clinical practice such as irinotecan, oxaliplatin, and capecitabine. Combination regimens using infusional 5-fluorouracil (5-FU)/leucovorin (LV) plus either oxaliplatin or irinotecan have demonstrated clinically meaningful, high efficacy in advanced CRC. Based on the results of the Intergroup trial N9741, FOLFOX4, a combination of infusional plus bolus 5-FU/LV and oxaliplatin, has emerged as the standard first-line therapy in the palliative setting. However, infusional 5-FU-based regimens carry the need for use of central venous lines and implantable ports to allow treatment on an outpatient basis and are thus inconvenient and expensive. The use of oral fluoropyrimidines (capecitabine or uracil/tegafur [UFT] plus LV) as substitutes for infusional 5-FU in combination protocols with oxaliplatin offers greater convenience, at the same time conceivably maintaining the high efficacy and tolerability observed with intravenous protocols. Various phase I/II trials have recently been reported that investigated oxaliplatin in combination with either capecitabine or UFT/LV in patients with advanced CRC. This review will detail the results of these trials focused on capecitabine-based combinations.     

Irinotecan in the treatment of colorectal cancer

Irinotecan, a water-soluble, semisynthetic derivative of camptothecin, is a key component of first- and second-line treatment regimens for metastatic colorectal cancer (CRC). In the first-line treatment of metastatic CRC, the results of two prospective, multicenter phase III trials have shown that the combination of irinotecan with bolus or infusional 5-fluorouracil (5FU)/leucovorin (LV) can significantly prolong survival compared with 5FU/LV alone, with a manageable side effects profile. In addition, irinotecan-based regimens, with or without oxaliplatin, may improve resectability of metastases and further increase patient survival. Studies of irinotecan in the first-line setting in combination with newer agents, such as bevacizumab, have shown impressive overall survival. In the second-line setting, irinotecan has demonstrated efficacy superior to that of best supportive care. Initial studies of irinotecan plus bolus 5FU/LV, and the preliminary results from trials of irinotecan plus infusional 5FU/LV in the adjuvant setting, have been disappointing; however, for the largest trial, the Pan-European Trial in Adjuvant Colon Cancer, results with sufficient follow-up are pending. Irinotecan has an acceptable tolerability profile and is not associated with cumulative toxicities in patients with metastatic CRC; regimens containing irinotecan extend treatment duration and improve survival. New regimens and adjunctive therapies are being explored to reduce the incidence of common complications of irinotecan treatment, such as diarrhea and neutropenia.     

Second-line chemotherapy use in metastatic colon cancer varies by disease responsiveness

BACKGROUND: Improved survival of patients with metastatic colorectal cancer (CRC) has been shown to correlate with increased utilization of the 3 active cytotoxic chemotherapeutic agents: 5-fluorouracil (5-FU), irinotecan, and oxaliplatin, usually administered in 2 lines of therapy. However, it is unclear which patient, disease, and treatment characteristics are associated with the utilization of a second-line regimen. PATIENTS AND METHODS: We performed a retrospective chart review. Patients with metastatic CRC treated with bevacizumab outside of a clinical trial and any infusional 5-FU/leucovorin (LV) regimen off-protocol (ie, 5-FU/LV/irinotecan [FOLFIRI]/bevacizumab or 5-FU/LV/oxaliplatin [FOLFOX]/bevacizumab) at the University of Texas M. D. Anderson Cancer Center between February 2004 and September 2005 were included. Prespecified characteristics of age, tumor burden, severe toxicity, and front-line regimen efficacy were compared with exploratory analyses of additional patient, disease, and treatment characteristics. RESULTS: Eighty-seven sequential patients treated with the specified front-line regimens were identified. Seventy-six percent of the eligible patients were treated with a second-line regimen. Despite equal treatment durations, patients with a better response of stable disease were significantly less likely to receive a third cytotoxic agent than patients with a partial response (68% vs. 95%; odds ratio, 8.2; P = .02) due to declining performance status (86%) or patient preference (14%). This was associated with a decreased 2-year overall survival (86% vs. 55%). Neither age, tumor burden, nor development of toxicities were associated with a different utilization of a second-line regimen. CONCLUSION: Failure to obtain a response to initial chemotherapy for metastatic disease appears to be associated with decreased utilization of a second-line regimen.     

Capecitabine plus oxaliplatin for the treatment of colorectal cancer

Based on improved safety and efficacy results, advanced colorectal cancer (CRC) treatment has recently shifted from intravenous bolus 5-fluorouracil (5-FU) monotherapy to standard combinations of prolonged intravenous 5-FU infusion with either oxaliplatin (FOLFOX) or irinotecan (FOLFIRI). Capecitabine, a rationally designed oral fluoropyrimidine that is converted into 5-FU preferentially at the tumor site, could replace infusional 5-FU as the mainstay of combined chemotherapy treatment for metastatic CRC. Evidently, oral medication obviates the drawbacks of prolonged intravenous infusion. The combination of capecitabine and oxaliplatin is especially attractive owing to its favorable tolerability profile, good activity and convenient administration schedule. Phase III trials comparing capecitabine/oxaliplatin with infusional regimens of 5-FU +/- LV and oxaliplatin in advanced CRC show similar toxicity and efficacy outcomes with both regimens. Capecitabine has the potential to replace 5-FU/LV as the optimal combination partner for oxaliplatin at a higher cost. Capecitabine and oxaliplatin concomitantly with radiation therapy has been evaluated before surgery in rectal cancer treatment. The combination of capecitabine and oxaliplatin, with or without bevacizumab, a monoclonal antibody blocking VEGF, is also being evaluated in early stage colon cancer.     

Bevacizumab combined with standard fluoropyrimidine-based chemotherapy regimens to treat colorectal cancer

For several decades, 5-fluorouracil (5-FU) with or without leucovorin defined the standard of care for the treatment of metastatic colorectal cancer (CRC). The addition of other chemotherapy regimens to 5-FU has improved survival, but often at the expense of increased toxicity. Recent advances in our understanding of the molecular basis of CRC have led to the production of novel targeted agents, such as bevacizumab (Avastin). Bevacizumab is currently approved for the first-line treatment of metastatic CRC and is currently being tested in combination with standard therapies for a range of indications. Phase II/III trials have demonstrated that the addition of bevacizumab to 5-FU-based first-line chemotherapy improves survival, progression-free survival and response rate compared with chemotherapy alone. Combination therapy does not appear to exacerbate side effects known to be associated with the chemotherapy regimen. The most common side effects attributable to bevacizumab therapy include hypertension, proteinuria and bleeding. Although uncommon, gastrointestinal perforation and arterial thromobembolic events are the most serious side effects reported to date. Bevacizumab is currently being evaluated in combination with oxaliplatin (Eloxatin)-based therapies and preliminary data are encouraging. Ongoing trials of bevacizumab in combination with standard first-line chemotherapy regimens will evaluate bevacizumab's potential in a range of cancer types. .     

A randomised phase II study of irinotecan in combination with 5-FU/FA compared with irinotecan alone as second-line treatment of patients with metastatic colorectal carcinoma

BACKGROUND: We conducted a randomised phase II study to compare irinotecan monotherapy with irinotecan in combination with infusional 5-fluorouracil/folinic acid (5-FU/FA) regarding efficacy and safety of these regimens in second-line therapy after failed fluoropyrimidine therapy in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: 55 patients with mCRC after failure of a first-line therapy were randomised to receive either irinotecan 80 mg/m2 followed by FA 500 mg/m2 and 5-FU 2,000 mg/m2 24 h weekly for 6 weeks, with courses repeated on day 50 (arm A), or irinotecan 125 mg/m2 weekly for 4 weeks, with cycles repeated on day 43 (Arm B). RESULTS: Both regimens yielded a partial response rate of 11% with identical progression-free survival (3.7 months for both regimens) and similar overall survival (9.5 months for the combination therapy vs. 10.7 months for the monotherapy). Both regimens were very well tolerated, and the combination of irinotecan with 5-FU/FA did not result in increased toxicity. CONCLUSION: Our study confirms that irinotecan alone or in combination with infusional 5-FU/FA is an effective and safe regimen for CRC patients who failed first-line therapies. However, the role of 5-FU in addition to irinotecan for fluoropyrimidine failures remains unclear. Due to the small sample size, a decision cannot be made which therapy should be preferred, and a significant contribution to the efficacy of single-agent irinotecan is not obvious from this small randomised phase II trial.     

Adjuvant therapy for colon cancer 2005: new options in the twenty-first century

The most effective current regimen for adjuvant treatment of surgically resected stage III colon cancer is the FOLFOX regimen of oxaliplatin, 5-FU and LV for 12 weeks, with a proportional risk reduction of 45% compared with approximately 36% for 5-FU/LV regimens. Infusion regimens of 5-FU with and without LV have been shown to confer equivalent benefit to bolus regimens in reducing the risk of cancer recurrence, but with lesser toxicity profiles. Oral 5-FU prodrug regimens have similarly shown equivalent benefit to bolus regimens, and toxicity comparable to infusional regimens, but with the added convenience over 5-FU infusion therapy. The addition of irinotecan to 5-FU and LV regimens has not demonstrated an advantage compared with 5-FU/LV treatments in the adjuvant setting.     

Role of tyrosine kinase inhibitors in the treatment of advanced colorectal cancer

Colorectal cancer (CRC) is a common health problem in Western countries. In advanced disease, either FOLFOX (oxaliplatin/5-fluorouracil [5-FU]/leucovorin [LV]) or FOLFIRI (irinotecan/LV/5-FU) are accepted first-line chemotherapy regimens, but median survival appears to plateau with a chemotherapy-only approach. The use of epidermal growth factor receptor (EGFR)- and vascular endothelial growth factor (VEGF)-targeting monoclonal antibodies has increased the median survival of patients with advanced CRC beyond 20 months. However, the precise role of cetuximab, panitumumab and bevacizumab in combination with different chemotherapeutic regimens is still being determined in first- and second-line settings. The activity and tolerance of the EGFR tyrosine kinase inhibitors (TKIs), gefitinib erlotinib, and EKB-569, alone or in combination with chemotherapy, have been explored in patients with metastatic CRC. Regarding VEGF receptor TKIs, 2 phase III clinical trials determined the role of vatalanib in combination with FOLFOX. Efficacy of the oral multitargeted TKIs sorafenib and sunitinib is under investigation. This article aims to review the role of TKIs in advanced CRC.     

A phase I study of the chinese herbal medicine PHY906 as a modulator of irinotecan-based chemotherapy in patients with advanced colorectal cancer

PHY906 is a novel Chinese herbal preparation that has been used in the Orient for over 1800 years to treat a wide range of gastrointestinal side effects including diarrhea, abdominal cramps, vomiting, fever, and headache. Preclinical and clinical studies were conducted to further investigate the biologic and clinical activities of this herbal medicine. To ensure standardization and maintain interbatch reliability of PHY906, high performance liquid chromatography (HPLC) was used to establish a "chemical fingerprint" of PHY906. In vivo preclinical studies using the murine Colon 39 tumor model showed that PHY906 protected against the weight loss associated with irinotecan treatment. In the presence of PHY906, mice were able to tolerate otherwise lethal doses of irinotecan. Significantly improved antitumor activity and overall survival were observed in animals treated with the combination of irinotecan and PHY906 versus irinotecan alone. The combination of PHY906 with irinotecan, 5-fluorouracil (5-FU), and leucovorin (LV) also resulted in at least additive antitumor activity with no increased host toxicity. Based on these in vivo studies, a phase I multicenter, double-blind, randomized, placebo-controlled, dose escalation, cross-over study of PHY906 as a modulator of the weekly, bolus regimen of irinotecan, 5-FU, and LV (IFL) in the first-line treatment of patients with advanced colorectal cancer (CRC) was conducted. The specific objectives of this clinical trial were to determine the safety and tolerability of PHY906 when administered concomitantly with the bolus, weekly IFL regimen. Treatment with PHY906 did not alter the pharmacokinetics of 5-FU, irinotecan, or the irinotecan metabolite SN-38.     

Metastatic rectal cancer responding to third-line therapy employing bevacizumab after failure of oxaliplatin and irinotecan: case report

A 61-year-old female with surgically treated rectal cancer that had metastasized to lung and lymph nodes was treated with bevacizumab (BV) plus 5-fluorouracil (5-FU) and leucovorin (LV) as third-line chemotherapy after treatment failures with infusional 5-FU, LV and oxaliplatin (FOLFOX regimen); and infusional 5-FU, LV and irinotecan (FOLFIRI regimen). After four cycles of treatment, a computed tomography scan revealed reduced sizes of the lung and lymph node metastases. Tumor response has still been maintained after six cycles of treatment, and the chemotherapeutic response was evaluated as partial response according to the Response Evaluation Criteria In Solid Tumor guidelines. Manageable toxicity included grade 2 hypertension, grade 1 epistaxis and grade 1 stomatitis. Although there are no clinical trial results supporting the use of BV-containing therapy as third-line chemotherapy for advanced colorectal cancer, BV plus 5-FU and LV was effective and feasible in our patient with colon cancer that had progressed after treatment with 5-FU, irinotecan and oxaliplatin.     

The cost-effectiveness of bevacizumab in the first-line treatment of metastatic colorectal cancer in England and Wales

BackgroundBevacizumab is a humanised monoclonal antibody, which has demonstrated significant activity in metastatic colorectal cancer. The aim of this study is to estimate the cost-effectiveness of adding bevacizumab to chemotherapy for patients with untreated metastatic colorectal cancer.MethodsA decision-analytic model was developed to estimate the lifetime costs and benefits of adding bevacizumab to irinotecan plus FU/LV (IFL) or 5-FU/LV alone. Effectiveness outcomes, health utilities and resource use data were derived from recent bevacizumab RCTs and from the literature.ResultsAdding bevacizumab to IFL costs approximately £62,857 per QALY gained. Adding bevacizumab to 5-FU/LV costs approximately £88,436 per QALY gained. The acquisition cost of bevacizumab is a key determinant of its cost-effectiveness. The probability that bevacizumab has a cost-effectiveness ratio that is better than £30,000 per QALY gained is close to zero.ConclusionsGiven high acquisition costs in relation to clinical benefits, bevacizumab is unlikely to represent a cost-effective use of NHS resources.     

Addition of bevacizumab to bolus fluorouracil and leucovorin in first-line metastatic colorectal cancer: results of a randomized phase II trial.

PURPOSE: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor, increases survival when combined with irinotecan-based chemotherapy in first-line treatment of metastatic colorectal cancer (CRC). This randomized, phase II trial compared bevacizumab plus fluorouracil and leucovorin (FU/LV) versus placebo plus FU/LV as first-line therapy in patients considered nonoptimal candidates for first-line irinotecan. PATIENTS AND METHODS: Patients had metastatic CRC and one of the following characteristics: age > or = 65 years, Eastern Cooperative Oncology Group performance status 1 or 2, serum albumin < or = 3.5 g/dL, or prior abdominal/pelvic radiotherapy. Patients were randomly assigned to FU/LV/placebo (n = 105) or FU/LV/bevacizumab (n = 104). The primary end point was overall survival. Secondary end points were progression-free survival, response rate, response duration, and quality of life. Safety was also assessed. RESULTS: Median survival was 16.6 months for the FU/LV/bevacizumab group and 12.9 months for the FU/LV/placebo group (hazard ratio, 0.79; P = .16). Median progression-free survival was 9.2 months (FU/LV/bevacizumab) and 5.5 months (FU/LV/placebo); hazard ratio was 0.50; P = .0002. Response rates were 26.0% (FU/LV/bevacizumab) and 15.2% (FU/LV/placebo) (P = .055); duration of response was 9.2 months (FU/LV/bevacizumab) and 6.8 months (FU/LV/placebo); hazard ratio was 0.42; P = .088. Grade 3 hypertension was more common with bevacizumab treatment (16% v 3%) but was controlled with oral medication and did not cause study drug discontinuation. CONCLUSION: Addition of bevacizumab to FU/LV as first-line therapy in CRC patients who were not considered optimal candidates for first-line irinotecan treatment provided clinically significant patient benefit, including statistically significant improvement in progression-free survival.     

Review of the role of CPT-11 in the treatment of colorectal cancer

Colorectal cancer (CRC) is the second leading cause of cancer death in Western countries, and although the treatment of advanced CRC has progressed substantially, the improvements in response rates have not always been translated into a significant survival benefit. Until recently, the standard therapy for advanced CRC was a variety of biomodulated 5-fluorouracil (5-FU) regimens. 5-FU was used as first- or second-line therapy, and a different 5-FU regimen was used second line if first-line 5-FU therapy failed. Typically, the survival times for these patients were short and their quality of life poor. In recent years, a variety of new agents have emerged that have demonstrated activity in the treatment of advanced CRC. Of these, irinotecan (CPT-11) and oxaliplatin in combination with 5-FU and folinic acid (FA) have yielded the most promising results. However, only CPT-11 combined with either bolus or high-dose infusional 5-FU/FA, in randomized phase III studies, has demonstrated an increased response rate and median time to progression, producing a significant and clinically relevant survival advantage. In 2 randomized phase III studies, oxaliplatin/5-FU/FA demonstrated a clear increase in response rate over 5-FU/FA alone but failed to demonstrate a survival advantage. CPT-11 was approved by the Food and Drug Administration in April 2000 for the first-line treatment of advanced CRC in combination with 5-FU/FA.