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

State-of-the-Art Management of Colorectal Cancer: Treatment Advances and Innovation

Colorectal cancer (CRC) remains a significant global health challenge, ranking among the leading causes of cancer-related morbidity and mortality worldwide. Recent advancements in molecular characterization have revolutionized our understanding of the heterogeneity within colorectal tumors, particularly in the context of tumor sidedness. Tumor sidedness, referring to the location of the primary tumor in either the right or left colon, has emerged as a critical factor influencing prognosis and treatment responses in metastatic CRC. Molecular underpinnings of CRC, the impact of tumor sidedness, and how this knowledge guides therapeutic decisions in the era of precision medicine have led to improved outcomes and better quality of life in patients. The emergence of circulating tumor DNA as a prognostic and predictive tool in CRC heralds promising advancements in the diagnosis and monitoring of the disease. This innovation facilitates better patient selection for exploration of additional treatment options. As the field progresses, with investigational agents demonstrating potential as future treatments for refractory metastatic CRC, new avenues for enhancing outcomes in this challenging disease are emerging.

Comparison of UGT1A1 Polymorphism as Guidance of Irinotecan Dose Escalation in RAS Wild-Type Metastatic Colorectal Cancer Patients Treated With Cetuximab or Bevacizumab Plus FOLFIRI as the First-Line Therapy

Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) polymorphism plays a crucial role in the increased susceptibility and toxicity of patients to irinotecan. This retrospective, observational study compared the clinical outcomes and adverse events (AEs) in RAS wild-type metastatic colorectal cancer (mCRC) patients treated with cetuximab or bevacizumab plus FOLFIRI with UGT1A1 genotyping and irinotecan dose escalation as the first-line therapy. In total, 173 patients with mCRC with RAS wild-type were enrolled. Among them, 98 patients were treated with cetuximab, whereas 75 patients were treated with bevacizumab. All patients received irinotecan dose escalation based on UGT1A1 genotyping. We compared the progression-free survival (PFS), overall survival (OS), objective response rates (ORRs), disease control rates (DCRs), metastatectomy, and severe adverse events (SAEs) between the two groups. The clinical effects of primary tumor sidedness and target therapy crossover were further analyzed. Over a median follow-up of 23.0 months [interquartile range (IQR), 15.032.5 months], no significant differences were observed between the cetuximab and bevacizumab groups in PFS [18.0 months vs. 14.0 months; 95% confidence interval (CI), 0.5171.027; hazard ratio (HR), 0.729; p=0.071], OS (40.0 months vs. 30.0 months; 95% CI, 0.4101.008; HR, 0.643; p=0.054), ORR (65.3% vs. 62.7%; p=0.720), DCR (92.8% vs. 86.7%; p=0.175), metastatectomy (36.7% vs. 29.3%; p=0.307), and SAEs (p=0.685). Regardless of primary tumor sidedness and target therapy crossover, no significant differences were noted in efficacy and safety between the two groups (all p>0.05). Our results revealed that patients with wild-type RAS mCRC, regardless of biologics, with UGT1A1 genotyping can tolerate escalated doses of irinotecan and potentially achieve a more favorable clinical outcome without significantly increased toxicity.

Pyrimidine Biosynthetic Enzyme CAD: Its Function, Regulation, and Diagnostic Potential

CAD (Carbamoyl-phosphate synthetase 2, Aspartate transcarbamoylase, and Dihydroorotase) is a multifunctional protein that participates in the initial three speed-limiting steps of pyrimidine nucleotide synthesis. Over the past two decades, extensive investigations have been conducted to unmask CAD as a central player for the synthesis of nucleic acids, active intermediates, and cell membranes. Meanwhile, the important role of CAD in various physiopathological processes has also been emphasized. Deregulation of CAD-related pathways or CAD mutations cause cancer, neurological disorders, and inherited metabolic diseases. Here, we review the structure, function, and regulation of CAD in mammalian physiology as well as human diseases, and provide insights into the potential to target CAD in future clinical applications.

Treatment sequencing of metastatic colorectal cancer based on primary tumor location

Colorectal cancer is a heterogeneous disease with various clinical, molecular, and embryological differences related to the origin of the tumor from the right or left colon. Recent studies have demonstrated that tumor sidedness has both a prognostic and predictive value in metastatic colorectal cancer . Patients whose primary tumor originates from the left side of the colon and whose tumor's genome encodes wild-type RAS and BRAF should be offered cetuximab or panitumumab in the first-line treatment of metastatic disease or in subsequent lines. For tumors originating from the right side of the colon, anti-angiogenic treatment, particularly bevacizumab, is an option for this poor prognostic group until better options become available. Specifically, an aggressive initial approach with FOLFOXIRI plus bevacizumab is a treatment option in right-sided tumors under investigation. This report reviews the available data for the treatment of metastatic colorectal cancer according to the location of the primary tumor and proposes the optimal treatment sequencing strategy incorporating the site of origin of the tumor and molecular information into the decision-making process.

The impact of primary tumor sidedness on survival in early-onset colorectal cancer by stage: A National Veterans Affairs retrospective analysis

BACKGROUND

The incidence of early-onset colorectal cancer (EOCRC) is rising. Left-sided colorectal cancer (LCC) is associated with better survival compared to right-sided colon cancer (RCC) in metastatic disease. NCCN guidelines recommend the addition of EGFR inhibitors to KRAS/NRAS WT metastatic CRC originating from the left only. Whether laterality impacts survival in locoregional disease and EOCRC is of interest.

METHODS

65,940 CRC cases from the National VA Cancer Cube Registry (2001-2015) were studied. EOCRC (2096 cases) was defined as CRC diagnosed at <50 years. Using ICD codes, RCC was defined from the cecum to the hepatic flexure (C18.0-C18.3), and LCC from the splenic flexure to the rectum (C18.5-18.7; C19 and C20).

RESULTS

EOCRC is more likely to originate from the left side (66.65% LCC in EOCRC vs. 58.77% in CRC). Overall, LCC has better 5-year Overall Survival (OS) than RCC in stages I (61.67% vs. 58.01%) and III (46.1% vs. 42.1%) and better 1-year OS in stage IV (57.79% vs. 49.49%). Stage II RCC has better 5-year OS than LCC (53.39% vs. 49.28%). In EOCRC, there is no statistically significant difference between LCC and RCC in stages I-III. Stage IV EOCRC patients with LCC and RCC have a 1-year OS of 73.23% and 59.84%, respectively.

CONCLUSION

In EOCRC, LCC is associated with better OS than RCC only stage IV. In the overall population, LCC is associated with better OS in all stages except stage II. The better prognosis of stage II RCC might be due to the high incidence of mismatch repair deficient tumors in this subpopulation.

Impact of biomarkers and primary tumor location on the metastatic colorectal cancer first-line treatment landscape in five European countries

Background: Advances in therapies for patients with metastatic colorectal cancer (mCRC) and improved understanding of prognostic and predictive factors have impacted treatment decisions. Materials & methods: This study used a large oncology database to investigate patterns of monoclonal antibody (mAb) plus chemotherapy treatment in France, Germany, Italy, Spain and the UK in mCRC patients treated in first line in 2018. Results: Anti-EGFR mAbs were most often administered to patients with RAS wild-type mCRC and those with left-sided tumors, while anti-VEGF mAbs were preferred in RAS mutant and right-sided tumors. Adopted treatment strategies differed between countries, largely due to reimbursement. Conclusion: Biomarker status and primary tumor location steered treatment decisions in first line. Adopted treatment strategies differed between participating countries.

The Significance of Sidedness in Patients with Metastatic Colorectal Cancer Treated with Triplet First-line Chemotherapy

BACKGROUND

Recent data have shown that right-sided colon cancer carries poorer prognosis compared to left-sided tumors. This study was aimed to evaluate the progression-free survival, overall survival of patients with metastatic colon cancer of right-sided versus left-sided primaries treated with triplet chemotherapy regimen.

METHODS

The medical records of patients with metastatic colorectal cancer treated on phase I-II trial of combination Irinotecan, oxaliplatin, capecitabine, and bevacizumab were reviewed for sidedness of the primary. The analysis was performed for progression-free survival and overall survival according to the sidedness and other known prognostic factors.

RESULTS

Out of 53 patients treated with triplet therapy, 11 had right sided and 42 had left-sided primaries. The median age for right-sided primaries was 46 (range 24-55) compared to 53 (range 32-74) in left-sided primaries. Median progression-free survival was 14 months for right vs 18 months for left sided tumors (Hazard ratio 0.72, 95% confidence interval 0.27-1.88, p=0.492) and median overall survival was 21 months for right vs 29 months for left sided tumors (Hazard ratio was 0.86, 95% CI 0.32-2.26, p=0.752).

CONCLUSION

First-line triplet chemotherapy may overcome the difference in prognosis between right sided and left sided primaries in metastatic colorectal cancer. A larger analysis is warranted.

Cost-effectiveness analysis of selective first-line use of biologics for unresectable RAS wild-type left-sided metastatic colorectal cancer

Background

Evidence from a retrospective analysis of multiple large phase iii trials suggested that primary tumour location (ptl) in RAS wild-type metastatic colorectal cancer (wtRAS mcrc) might have predictive value with respect to response to drug therapies. Recent studies also show a potential preferential benefit for epidermal growth factor inhibitors (egfris) for left-sided tumours. In the present study, we aimed to determine the incremental cost-effectiveness ratio (icer) for the first-line use of an egfri for patients with left-sided wtRAS mcrc.

Methods

We developed a state-transition model to determine the cost effectiveness of alternative treatment strategies in patients with left-sided mcrc:■ Standard of care■ Use of an egfri in first-line therapyThe cohort for the study consisted of patients diagnosed with unresectable wtRAS mcrc with an indication for chemotherapy and previously documented ptl. Model parameters were obtained from the published literature and calibration. The perspective was that of a provincial ministry of health in Canada. We used a 5-year time horizon and an annual discount rate of 1.5%.

Results

Selecting patients for first-line egfri treatment based on left-sided location of their colorectal primary tumour was more effective than the standard of care, resulting in an increase in quality-adjusted life-years (qalys) of 0.226 (or 0.644 life-years gained). However, the strategy was also more expensive, costing an average of $60,639 more per patient treated. The resulting icer was $268,094 per qaly. A 35% price reduction in the cost of egfri would be needed to make this strategy cost-effective at a willingness-to-pay threshold (wtp) of $100,000 per qaly.

Conclusions

Selective use of an egfri based on ptl was more cost-effective than unselected use of those agents; however, based on traditional wtp thresholds, it was still not cost-effective. While awaiting the elucidation of more precise predictive biomarkers that might improve cost-effectiveness, the price of egfris could be reduced to meet the wtp threshold.

Predictive factors of histological response of colorectal liver metastases after neoadjuvant chemotherapy

BACKGROUND

Colorectal cancer is the third most common cancer in men and the second most common in women worldwide. Almost a third of the patients has or will develop liver metastases. Neoadjuvant chemotherapy (NAC) has recently become nearly systematic prior to surgery of colorectal livers metastases (CRLMs). The response to NAC is evaluated by radiological imaging according to morphological criteria. More recently, the response to NAC has been evaluated based on histological criteria of the resected specimen. The most often used score is the tumor regression grade (TRG), which considers the necrosis, fibrosis, and number of viable tumor cells.

AIM

To analyze the predictive factors of the histological response, according to the TRG, on CRLM surgery performed after NAC.

METHODS

From January 2006 to December 2013, 150 patients who had underwent surgery for CRLMs after NAC were included. The patients were separated into two groups based on their histological response, according to Rubbia-Brandt TRG. Based on their TRG, each patient was either assigned to the responder (R) group (TRG 1, 2, and 3) or to the non-responder (NR) group (TRG 4 and 5). All of the histology slides were re-evaluated in a blind manner by the same specialized pathologist. Univariate and multivariate analyses were performed.

RESULTS

Seventy-four patients were classified as responders and 76 as non-responders. The postoperative mortality rate was 0.7%, with a complication rate of 38%. Multivariate analysis identified five predictive factors of histological response. Three were predictive of non-response: More than seven NAC sessions, the absence of a radiological response after NAC, and a repeat hepatectomy (P < 0.005). Two were predictive of a good response: A rectal origin of the primary tumor and a liver-first strategy (P < 0.005). The overall survival was 57% at 3 yr and 36% at 5 yr. The disease-free survival rates were 14% at 3 yr and 11% at 5 yr. The factors contributing to a poor prognosis for disease-free survival were: No histological response after NAC, largest metastasis > 3 cm, more than three preoperative metastases, R1 resection, and the use of a targeted therapy with NAC (P < 0.005).

CONCLUSION

A non-radiological response and a number of NAC sessions > 7 are the two most pertinent predictive factors of non-histological response (TRG 4 or 5).

Weekly alternate intensive regimen FIrB/FOx in metastatic colorectal cancer patients: an update from clinical practice

Background

Several trials evaluated the role of intensive regimens, made of triplet chemotherapies plus bevacizumab, as first-line treatment for patients with metastatic colorectal cancer (mCRC). We previously reported, in a Phase II prospective study, the efficacy and the tolerability of FIrB/FOx regimen, reporting interesting results in terms of received dose intensities (rDIs) and safety.

Methods

We reported a retrospective update of 85 patients treated with FIrB/FOx, an intensive regimen of 5-fluorouracil, bevacizumab, and weekly alternate irinotecan and oxaliplatin, to confirm its feasibility in “real life”. Subgroup analyses were performed, particularly among patients treated with standard and modified FIrB/FOx (based on age, performance status, and/or comorbidities).

Results

Overall, 3-month objective response rate (ORR) and 6-month ORR were 75.9% and 55.3%, respectively. Median progression-free survival (PFS) and median overall survival (OS) were 14.4 and 34.9 months, respectively. Among the patients treated with standard and modified regimens, 3-month ORR, PFS, and OS were 75.8% and 76% (P=1.0000), 14.4 and 14.4 months (P=0.8589), and 37.8 and 26.6 months (P=0.7746), respectively. Among the K/NRAS wild-type and K/NRAS mutant patients, 3-month ORR, PFS, and OS were 95.2% and 74.5% (P=0.0526), 15.3 and 14.4 months (P=0.8753), and 37.8 and 51.4 months (P=0.8527), respectively. The rDIs were ≥80% of full doses both in the standard and in the modified regimens subgroups. Cumulative G3/4 toxicities were neutropenia (14.1%), diarrhea (17.6%), asthenia (9.4%), vomiting (5.6%), and hypertension (16.5%).

Conclusion

This update shows that intensive regimens such as FIrB/FOx are also feasible options for first-line treatment of mCRC patients in the “real-life” setting.

Composite Hydrogel Embedded with Porous Microspheres for Long-Term pH-Sensitive Drug Delivery

IMPACT STATEMENT

A composite hydrogel embedded with porous microspheres fabricated by phase separation methods was developed and showed excellent long-term anticancer drug delivery capability to cancer cells.

Colorectal Cancer Biomarkers in the Era of Personalized Medicine

The 5-year survival probability for patients with metastatic colorectal cancer has not drastically changed over the last several years, nor has the backbone chemotherapy in first-line disease. Nevertheless, newer targeted therapies and immunotherapies have been approved primarily in the refractory setting, which appears to benefit a small proportion of patients. Until recently, rat sarcoma (RAS) mutations remained the only genomic biomarker to assist with therapy selection in metastatic colorectal cancer. Next generation sequencing has unveiled many more potentially powerful predictive genomic markers of therapy response. Importantly, there are also clinical and physiologic predictive or prognostic biomarkers, such as tumor sidedness. Variations in germline pharmacogenomic biomarkers have demonstrated usefulness in determining response or risk of toxicity, which can be critical in defining dose intensity. This review outlines such biomarkers and summarizes their clinical implications on the treatment of colorectal cancer. It is critical that clinicians understand which biomarkers are clinically validated for use in practice and how to act on such test results.

Integrating Biomarkers and Targeted Therapy Into Colorectal Cancer Management

There have been substantial advances in the treatment of metastatic colorectal cancer (mCRC) over the past 15 years. Molecular characteristics of mCRC and identification of specific mutations can serve as predictive and prognostic indicators of disease and response to targeted therapies. When incorporated into clinical decision-making, these biomarkers can serve as critical tools in personalizing therapy to ensure the best outcomes. Additional improvements in the survival of patients with mCRC will be made possible with the identification of new predictive molecular biomarkers and their evaluation using rational and innovative clinical trials.

Anti-EGFR monoclonal antibody panitumumab for the treatment of patients with metastatic colorectal cancer: an overview of current practice and future perspectives

INTRODUCTION

Targeted agents alone or in combination with chemotherapy are current standard of treatment for metastatic colorectal cancer (mCRC). Panitumumab is a fully human monoclonal antibody which inhibits the epidermal growth factor receptor (EGFR). It is currently approved in combination with chemotherapy in first- and second-line and as a monotherapy in chemorefractory patients. RAS gene mutations confer resistance to anti-EGFR agents; thus, panitumumab is restricted to the treatment of RAS wild-type (WT) tumors. Areas covered: This review explores the available data on panitumumab and presents new perspectives on predictive markers of anti-EGFR efficacy including primary tumor sidedness and BRAF mutations. Other details covered include panitumumab's mechanism of action, pharmacokinetics, pharmacodynamics and safety aspects of the therapy as well as mechanisms of secondary resistance and future prospects of treatment in different settings. Expert opinion: Panitumumab has significantly added to the treatment armamentarium for RAS WT mCRC. The effort spent in identifying predictive biomarkers of panitumumab efficacy has been of pivotal importance to development of the molecular selection of patients with mCRC. Primary and secondary resistance, however, still represent important issues. Novel strategies to overcome those issues are currently underway with promising results which highlight the potential use of panitumumab in combination with other targeted agents in the future.

Folic Acid-Metabolizing Enzymes Regulate the Antitumor Effect of 5-Fluoro-2'-Deoxyuridine in Colorectal Cancer Cell Lines

In colorectal cancer chemotherapy, the current standard of care includes combination therapy with 5-fluorouracil (5-FU) and leucovorin (LV). However, the factors that determine the LV-mediated enhancement of 5-FU antitumor activity are not fully understood. Therefore, we investigated the roles of thymidine synthase (TYMS), folate receptor 1 (FOLR1), dihydrofolate reductase (DHFR), phosphoribosylglycinamide formyltransferase (GART), methylenetetrahydrofolate dehydrogenase (MTHFD1), and methylenetetrahydrofolate reductase (MTHFR) in LV-mediated enhancement of 5-fluoro-2′-deoxyuridine (FdUrd) cytotoxicity in vitro as a model of 5-FU antitumor activity. These genes were downregulated in DLD-1 and HCT116 human colorectal cancer cells by using small-interfering RNA. Reduced expression of TYMS mRNA significantly increased FdUrd cytotoxicity by 100- and 8.3-fold in DLD-1 and HCT116 cells, respectively. In contrast, reducing the expression of FOLR1, DHFR, GART, MTHFD1, and MTHFR decreased FdUrd cytotoxicity by 2.13- to 12.91-fold in DLD-1 cells and by 3.52- to 10.36-fold in HCT116 cells. These results demonstrate that folate metabolism is important for the efficacy of FdUrd. Overall, the results indicate that it is important to clarify the relationship between folate metabolism-related molecules and 5-FU treatment in order to improve predictions of the effectiveness of 5-FU and LV combination therapy.

Methylator phenotype in colorectal cancer: A prognostic factor or not?

Colorectal cancer (CRC) is due to different types of genetic alterations that are translated into different phenotypes. Among them, CpG island methylator phenotype (CIMP+) is the most recently involved in carcinogenesis of some CRC. The malignant transformation in this case is mainly due to the transcriptional inactivation of tumor suppressor genes. CIMP+ are reported to be more frequently found in the elderly and in women. The tumors are more frequently located in the proximal part of the colon, BRAF mutated and are associated with microsatellite instability (MSI) phenotype. All sporadic MSI CRC belong to the methylator phenotype, however some non MSI CRC may also harbor a methylator phenotype. The prognostic value of CIMP is not well known. Most studies show a worse prognosis in CIMP+ CRC, and adjuvant treatments seem to be more efficient. We review here the current knowledge on prognostic and predictive values in CIMP+ CRC.

Influence of the duration of intravenous drug administration on tumor uptake

Enhancing tumor uptake of anticancer drugs is an important therapeutic goal, because insufficient drug accumulation is now considered to be an important reason for unresponsiveness or resistance to antitumor therapy. Based on a mechanistic tumor uptake model describing tumor exposure to molecules of different molecular size after bolus administration, we have investigated the influence of the duration of intravenous administration on tumor uptake. The model integrates empirical relationships between molecular size and drug disposition (capillary permeability, interstitial diffusivity, available volume fraction, and plasma clearance), together with a compartmental pharmacokinetics model and a drug/target binding model. Numerical simulations were performed using this model for protracted intravenous drug infusion, a common mode of administration of anticancer drugs. The impact of mode of administration on tumor uptake is described for a large range of molecules of different molecular size. Evaluation was performed not only for the maximal drug concentration achieved in the tumor, but also for the dynamic profile of drug concentration. It is shown that despite a lower maximal uptake for a given dose, infusion allows for a prolonged exposure of tumor tissues to both small- and large-sized molecules. Moreover, infusion may allow higher doses to be administered by reducing Cmax-linked toxicity, thereby achieving a similar maximal uptake compared to bolus administration.

Cost-effectiveness of gene-expression profiling for tumor-site origin

OBJECTIVES

Gene-expression profiling (GEP) reliably supplements traditional clinicopathological information on the tissue of origin (TOO) in metastatic or poorly differentiated cancer. A cost-effectiveness analysis of GEP TOO testing versus usual care was conducted from a US third-party payer perspective.

METHODS

Data on recommendation changes for chemotherapy, surgery, radiation therapy, blood tests, imaging investigations, and hospice care were obtained from a retrospective, observational study of patients whose physicians received GEP TOO test results. The effects of chemotherapy recommendation changes on survival were based on the results of trials cited in National Comprehensive Cancer Network and UpToDate guidelines. Drug and administration costs were based on average doses reported in National Comprehensive Cancer Network guidelines. Other unit costs came from Centers for Medicare & Medicaid Services fee schedules. Quality-of-life weights were obtained from literature. Bootstrap analysis estimated sample variability; probabilistic sensitivity analysis addressed parameter uncertainty.

RESULTS

Chemotherapy regimen recommendations consistent with guidelines for final tumor-site diagnoses increased significantly from 42% to 65% (net difference 23%; P<0.001). Projected overall survival increased from 15.9 to 19.5 months (mean difference 3.6 months; two-sided 95% confidence interval [CI] 3.2-3.9). The average increase in quality-adjusted life-months was 2.7 months (95% CI 1.5-4.3), and average third-party payer costs per patient increased by $10,360 (95% CI $2,982-$19,192). The cost per quality-adjusted life-year gained was $46,858 (95% CI $13,351-$104,269).

CONCLUSIONS

GEP TOO testing significantly altered clinical practice patterns and is projected to increase overall survival, quality-adjusted life-years, and costs, resulting in an expected cost per quality-adjusted life-year of less than $50,000.

Approaches to improve tumor accumulation and interactions between monoclonal antibodies and immune cells

Monoclonal antibodies (mAb) have become a mainstay in tumor therapy. Clinical responses to mAb therapy, however, are far from optimal, with many patients presenting native or acquired resistance or suboptimal responses to a mAb therapy. MAbs exert antitumor activity through different mechanisms of action and we propose here a classification of these mechanisms. In many cases mAbs need to interact with immune cells to exert antitumor activity. We summarize evidence showing that interactions between mAbs and immune cells may be inadequate for optimal antitumor activity. This may be due to insufficient tumor accumulation of mAbs or immune cells, or to low-affinity interactions between these components. The possibilities to improve tumor accumulation of mAbs and immune cells, and to improve the affinity of the interactions between these components are reviewed. We also discuss future directions of research that might further improve the therapeutic efficacy of antitumor mAbs.

Triplet chemotherapy in patients with metastatic colorectal cancer: toward the best way to safely administer a highly active regimen in clinical practice

A major problem concerning the addition of more drugs in a chemotherapy combination is designing a proper schedule assuring the balance between dose intensity of each drug, efficacy of the combination, and tolerability lessening the burden of drug toxicity. We evaluated triplet chemotherapy-based intensive regimens proposed as first-line treatment in patients with metastatic colorectal cancer. Using a FOLFOXIRI (5-fluorouracil [5-FU], irinotecan, and oxaliplatin) combination regimen, patients with metastatic colorectal cancer now have the possibility of longer survival, but disappointingly, with increased toxicities. Triplet chemotherapy regimen according to 5-fluorouracil, irinotecan /5-fluorouracil, oxaliplatin, characterized by timed flat-infusion 5-FU administration, without leucovorin, obtained efficacy equivalent to other reported similar combination regimens (5-FU, irinotecan, and oxaliplatin), with increased received 5-FU dose intensity and lower grade 3 to 4 neutropenia. To guarantee the proper balance between dose intensities, efficacy, and toxicity, triplet chemotherapy schedules could be further improved by abrogation of folinic acid and bolus 5-FU, a new and easy modality of 5-FU administration, such as timed flat-infusion 5-FU, associated with alternating irinotecan and oxaliplatin; this could favor diffusion of this intensive treatment in clinical practice.

How to improve exposure of tumor cells to drugs: promoter drugs increase tumor uptake and penetration of effector drugs

Solid tumors are characterized by an abnormal architecture and composition that limit the uptake and distribution of antitumor drugs. Over the last two decades, drugs have been identified that improve the tumor uptake and distribution of drugs that have direct antitumor effects. We propose to refer to these drugs as promoter drugs, and as effector drugs to drugs that have direct antitumor effects. Some promoter drugs have received regulatory approval, while others are in active clinical development. This review gives an overview of promoter drugs, by classifying them according to their mechanism of action: promoter drugs that modulate tumor blood flow, modify the barrier function of tumor vessels, induce tumor cell killing, and overcome stromal barriers. Eventually, we discuss those that we feel are the main conclusions to be drawn from promoter drug research that has been performed so far, and suggest areas of future investigation to improve the efficacy of promoter drugs in cancer therapy.

A decade of advances in cytotoxic chemotherapy for metastatic colorectal cancer

Over the past decade treatment for metastatic colorectal cancer (mCRC) has advanced beyond single-agent fluoropyrimidine use to include various cytotoxic combination regimens and novel targeted therapies. Despite the targeted therapy era, traditional cytotoxic agents remain the mainstay of therapy. Improvements in survival in mCRC can be attributed mostly to combination therapy, with enhanced efficacy due to optimization of fluoropyrimidine dosing and the addition of irinotecan and/or oxaliplatin. Despite the enormous progress, few patients with metastatic disease are cured. To realize that ambitious goal we need a better understanding of predictive molecular markers of response, mechanisms of drug toxicity, innate and acquired drug resistance as well as how to optimize cytotoxic agents in combination with newer targeted therapies.

A phase I study of an oral simulated FOLFOX with high dose capecitabine

BACKGROUND

A phase I study of high-dose capecitabine given over 2 days, along with oxaliplatin, bolus 5FU and leucovorin (LV), was designed to simulate FOLFOX6 without the need for infusional 5FU.

METHODS

Schedule A included oxaliplatin 100 mg/m(2), 5FU 400 mg/m(2), and LV 20 mg/m(2) (all given IV on days 1 and 15, 28 day cycle). Capecitabine was administered orally every 8 h x 6 doses, days 1 and 15. Schedule B excluded 5FU and LV, maintaining oxaliplatin and capecitabine. Pharmacokinetics were performed for capecitabine for 6 patients on each schedule.

RESULTS

36 patients were treated. The dose-limiting toxicities seen included nausea, dehydration, fatigue, hypotension and confusion. Minimal palmar-plantar erythrodysesthesia was seen. Myelosuppression was common, but not a dose limiting toxicity. The pharmacokinetic parameters for capecitabine were unaltered.

CONCLUSION

Using capecitabine to mimic FOLFOX6 is feasible and well tolerated with a toxicity profile that differs from standard 14-day capecitabine dosing, with less palmar-plantar erythrodysesthesia. The phase II dose for capecitabine in combination with oxaliplatin, 5FU, and LV is 1,500 mg/m(2)/dose or 2,250 mg/m(2)/dose in the absence of bolus 5FU/LV.

Review article: current management of metastatic colorectal cancer - the evolving impact of targeted drug therapies

BACKGROUND

The field of colorectal cancer chemotherapy has been transformed by the advent of molecule-specific drugs. Combined use of such drugs enhances tumour response rates, but controlled data quantifying the relative efficacy and cost-effectiveness of different drug combinations on overall survival remain scarce.

AIM

To conduct an overview of published clinical trials in advanced colorectal cancer, with the objective of framing provisional approaches to current management.

METHODS

An NCBI/PubMed search was performed using the strings, 'colorectal cancer' ('metastatic' or 'advanced' or 'palliative') and ('chemotherapy' or 'drug therapy' or 'targeted' or 'target-specific' or 'molecularly-targeted').

RESULTS

Combinations of target-specific drugs (with or without the DNA-alkylating agent oxaliplatin) have substantially enhanced colorectal cancer time to progression over the last decade and have also expedited surgical resection of liver metastases. Disease-free survival, overall survival and quality of life are favourably influenced.

CONCLUSIONS

Target-specific drugs improve palliative efficacy in the setting of advanced colorectal cancer. However, key issues persist as to the cost-effectiveness of these newer drug treatments, and further controlled trials are needed to resolve this important debate.

Association between DNA methylation and shortened survival in patients with advanced colorectal cancer treated with 5-fluorouracil based chemotherapy

PURPOSE

There are no good genomic markers of survival in patients with advanced colorectal cancer. The CpG island methylator phenotype (CIMP) marks a distinctive pathway in colorectal cancer. We sought to determine the prognostic significance of CIMP in advanced colorectal cancer patients treated with 5-fluorouracil (5-FU) in an Eastern Cooperative Oncology Group clinical trial.

EXPERIMENTAL DESIGN

We studied 188 patients enrolled on protocol E2290, a five-arm trial comparing 5-FU, 5-FU in combination with N-phosphonoacetyl-l-aspartic acid, oral leucovorin, i.v. leucovorin, or IFNalpha-2a in patients with advanced colorectal cancer. Methylation of MINT1, MINT31, hMLH1, p14ARF, and p16INK4a in DNA extracted from formalin-fixed paraffin-embedded specimens was evaluated by combined bisulfite restriction analysis, and methylation of MINT2 was studied by methylation-specific PCR.

RESULTS

Methylation frequencies were 21% for MINT1, 23% for MINT2, 24% for MINT31, 4% for hMLH1, 11% for p14ARF, and 17% for p16INK4a. Methylation of MINT1, MINT31, p14ARF, and p16INK4a were correlated, as expected. There was no association between methylation and clinicopathologic factors or response to therapy. Methylation of MINT1, MINT31, p14ARF, or p16INK4a was associated individually with shortened overall survival. Hazard ratios were 1.51 (P = 0.05) for MINT1, 1.70 (P = 0.006) for MINT31, 2.22 (P = 0.001) for p14ARF, and 1.51 (P = 0.05) for p16INK4a. Concurrent methylation of two or more genes of the CIMP-associated subset (MINT1, MINT31, p14ARF and p16INK4a) defined a group of cases with markedly reduced overall survival and hazard ratio was 3.22 (P < 0.0001 in multivariate analyses).

CONCLUSIONS

CIMP is associated with poor survival in advanced colorectal cancer patients.

Drug Resistance and the Solid Tumor Microenvironment

Resistance of human tumors to anticancer drugs is most often ascribed to gene mutations, gene amplification, or epigenetic changes that influence the uptake, metabolism, or export of drugs from single cells. Another important yet little-appreciated cause of anticancer drug resistance is the limited ability of drugs to penetrate tumor tissue and to reach all of the tumor cells in a potentially lethal concentration. To reach all viable cells in the tumor, anticancer drugs must be delivered efficiently through the tumor vasculature, cross the vessel wall, and traverse the tumor tissue. In addition, heterogeneity within the tumor microenvironment leads to marked gradients in the rate of cell proliferation and to regions of hypoxia and acidity, all of which can influence the sensitivity of the tumor cells to drug treatment. In this review, we describe how the tumor microenvironment may be involved in the resistance of solid tumors to chemotherapy and discuss potential strategies to improve the effectiveness of drug treatment by modifying factors relating to the tumor microenvironment.

Surrogate end points for median overall survival in metastatic colorectal cancer: literature-based analysis from 39 randomized controlled trials of first-line chemotherapy

PURPOSE

Our aims were to determine the correlations between progression-free survival (PFS), time to progression (TTP), and response rate (RR) with overall survival (OS) in the first-line treatment of metastatic colorectal cancer (MCRC), and to identify a potential surrogate for OS.

METHODS

Randomized trials of first-line chemotherapy in MCRC were identified, and statistical analyses were undertaken to evaluate the correlations between the end points.

RESULTS

Thirty-nine randomized controlled trials were identified containing a total of 87 treatment arms. Among trials, the nonparametric Spearman rank correlation coefficient (r(s)) between differences (Delta) in surrogate end points (DeltaPFS, DeltaTTP, and DeltaRR) and DeltaOS were 0.74 (95% CI, 0.47 to 0.88), 0.52 (95% CI, 0.004 to 0.81), 0.39 (95% CI, 0.08 to 0.63), respectively. The r(s) for DeltaPFS was not significantly different from the r(s) DeltaTTP (P = .28). Linear regression analysis was performed using hazard ratios for PFS and OS. There was a strong relationship between hazard ratios for PFS and OS; the slope of the regression line was 0.54 +/- 0.10, indicating that a novel therapy producing a 10% risk reduction for PFS will yield an estimated 5.4% +/- 1% risk reduction for OS.

CONCLUSION

In first-line chemotherapy trials for MCRC, improvements in PFS are strongly associated with improvements in OS. In this patient population, PFS may be an appropriate surrogate for OS. As a clinical end point, PFS offers increased statistical power at a given time of analysis and a significant lead time advantage compared with OS.

Efficacy of a nitric oxide-releasing nonsteroidal anti-inflammatory drug and cytotoxic drugs in human colon cancer cell lines in vitro and xenografts

We previously showed that NCX 4040 inhibits in vitro and in vivo tumor growth and induces apoptosis in human colon cancer cell lines. On the basis of these results, NCX 4040 antitumor activity in combination with 5-fluorouracil (5-FU) or oxaliplatin was evaluated in vitro and in vivo in human colon cancer models. The cytotoxicity of different NCX 4040 and 5-FU or oxaliplatin combination schemes was evaluated on a panel of colon cancer lines (LoVo, LoVo Dx, WiDr, and LRWZ) by the sulforhodamine B assay, and apoptosis was assessed by flow cytometry. NCX 4040 and 5-FU combination was always additive in vitro regardless of the scheme used. Sequential NCX 4040-->oxaliplatin treatment produced a strong synergism in three cell lines, with a ratio index ranging from 3.7 to 4. The synergistic effect was accompanied by apoptosis induction (up to 40%). In the in vivo experiments, xenografted mice were treated with the sequential combination of NCX 4040 and oxaliplatin, and apoptosis was evaluated immunohistochemically in excised tumors. Furthermore, in WiDr xenografts, this sequence caused a significantly higher reduction ( approximately 60%) in tumor growth compared with single-drug treatments and produced extensive apoptotic cell death (15.3%), significantly higher (P < 0.01) than that observed in untreated tumors (2.7%) or in tumors treated with NCX 4040 (5.1%) or oxaliplatin (5.7%) alone. These data show that NCX 4040 sensitizes colon cancer cell lines to the effect of antitumor drugs and suggests that their combination could be useful for the clinical management of colon cancer.

A computationally simple bivariate survival estimator for efficacy and safety

Both treatment efficacy and safety are typically the primary endpoints in Phase II, and even in some Phase III, clinical trials. Efficacy is frequently measured by time to response, death, or some other milestone event and thus is a continuous, possibly censored, outcome. Safety, however, is frequently measured on a discrete scale; in Eastern Cooperative Oncology Group clinical trial E2290, it was measured as the number of weekly rounds of chemotherapy that were tolerable to colorectal cancer patients. For the joint analysis of efficacy and safety, we propose a non-parametric, computationally simple estimator for the bivariate survival function when one time-to-event is continuous, one is discrete, and both are subject to right-censoring. The bivariate censoring times may depend on each other, but they are assumed to be independent of both event times. We derive a closed-form covariance estimator for the survivor function which allows for inference to be based on any of several possible statistics of interest. In addition, we derive its covariance with respect to calendar time of analysis, allowing for its use in sequential studies.

Phase III trial of fluorouracil-based chemotherapy regimens plus radiotherapy in postoperative adjuvant rectal cancer: GI INT 0144

PURPOSE

Adjuvant chemoradiotherapy after or before resection of high-risk rectal cancer improves overall survival (OS) and pelvic control. We studied three postoperative fluorouracil (FU) radiochemotherapy regimens.

PATIENTS AND METHODS

After resection of T3-4, N0, M0 or T1-4, N1, 2M0 rectal adenocarcinoma, 1,917 patients were randomly assigned to arm 1, with bolus FU in two 5-day cycles every 28 days before and after radiotherapy (XRT) plus FU via protracted venous infusion (PVI) 225 mg/m2/d during XRT; arm 2 (PVI-only arm), with PVI 42 days before and 56 days after XRT + PVI; or arm 3 (bolus-only arm), with bolus FU + leucovorin (LV) in two 5-day cycles before and after XRT, plus bolus FU + LV (levamisole was administered each cycle before and after XRT). Patients were stratified by operation type, T and N stage, and time from surgery.

RESULTS

Median follow-up was 5.7 years. Lethal toxicity was less than 1%, with grade 3 to 4 hematologic toxicity in 49% to 55% of the bolus arms versus 4% in the PVI arm. No disease-free survival (DFS) or OS difference was detected (3-year DFS, 67% to 69% and 3-year OS, 81% to 83% in all arms). Locoregional failure (LRF) at first relapse was 8% in arm 1, 4.6% in arm 2, and 7% in arm 3. LRF in T1-2, N1-2, and T3, N0-2 primaries who received low anterior resection (those most suitable for primary resection) was 5% in arm 1, 3% in arm 2, and 5% in arm 3.

CONCLUSION

All arms provide similar relapse-free survival and OS, with different toxicity profiles and central catheter requirements. LRF with postoperative therapy is low, justifying initial resection for T1-2, N0-2 and T3, and N0-2 anterior resection candidates.

Should continuous infusion 5-fluorouracil become the standard of care in the USA as it is in Europe?

The mechanism of action of 5-fluorouracil (5-FU) and its pharmacologic behavior are influenced by its mode of administration. Several clinical studies have been conducted with the purpose of evaluating the difference between the continuous (CI 5-FU) and the bolus infusion of 5-FU (BI 5-FU). We focus our review on the studies relevant to the treatment of colorectal cancer, both in the adjuvant and metastatic setting. While individual trials fail to show a survival benefit for CI 5-FU, a meta-analyses of 7 trials shows an improvement in overall survival (OS) over BI 5-FU in metastatic colorectal cancer treatment. All trials in the same setting reveal a different toxicity profile for CI 5-FU that is generally more favorable than BI 5-FU. In the adjuvant setting, CI 5-FU allows the duration of therapy to be shortened by half without compromising the efficacy. CI 5-FU is the regimen of choice when given concurrently with radiation. When given in combination with other cytotoxic agents, CI 5-FU seems to be associated with less toxicity and potentially higher efficacy. Oral fluoropyrimidines, especially capecitabine, appear to behave in similar manner to CI 5-FU and may offer a convenient alternative to the usage of infusion pumps and indwelling catheters. While clinical trials are ongoing to compare capecitabine to CI 5-FU, we believe that CI 5-FU should be offered to patients in the United States given its favorable toxicity profile and higher efficacy in several settings.

Phase I-II trial of weekly gemcitabine plus high-dose 5-fluorouracil and leucovorin in advanced pancreatic cancer

BACKGROUND

Pancreatic cancer is a dismal disease. Few drugs, including gemcitabine and 5-fluorouracil (5-FU), have notable antitumor effects against advanced pancreatic cancer. The purpose of the present study was to determine the maximum tolerated dose (MTD) of 5-FU and the efficacy and toxicity profile of weekly gemcitabine plus infusional 5-FU/leucovorin in advanced pancreatic cancer.

METHODS

Patients with histo-/cytologically confirmed, advanced pancreatic cancer were eligible. Treatment consisted of a 30-min infusion of gemcitabine (800 mg/m2), followed by a 24-h infusion of 5-FU and leucovorin (300 mg/m2) at day 1, day 8 and day 15 every 28 days, and was termed the GemFL24 regimen. The dose of 5-FU was escalated from 1600, 2000, to 2600 mg/m2 in the phase I study, and fixed MTD for subsequent enrolled patients.

RESULTS

Eighteen patients were enrolled in the phase I study, and 24 in phase II. The MTD of 5-FU was 2000 mg/m2, with major dose-limiting toxicities being febrile neutropenia and delayed recovery from neutropenia. The dose intensity of gemcitabine of the 35 patients with 5-FU dosage set at MTD was 593 mg/m2 per week. In the entire series of 42 patients, myelosuppression was the main toxicity, with grade 3 neutropenia in eight patients, and grade 3/4 thrombocytopenia in six. On an intention-to-treat analysis, the overall and clinical benefit response rates were 22% and 46%, respectively; with median progression-free and overall survival of 4.1 and 6.9 months, respectively.

CONCLUSIONS

The GemFL24 regimen is a feasible and moderately active treatment with manageable toxicities for advanced pancreatic cancer, and could be a basis for further combination with other anticancer drugs.

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.

Critical evaluation of current treatments in metastatic colorectal cancer

Fluorouracil (FU) has been the mainstay of treatment for metastatic colorectal cancer (mCRC) for many years. However, in recent years, newer chemotherapeutic agents, particularly irinotecan (Campostar; Pfizer Pharmaceuticals, New York, NY, http://www.pfizer.com) and more recently oxaliplatin (Eloxatin; Sanofi-Aventis Inc., New York, NY, http://www.sanofi-aventis.com), have been shown to improve survival in combination with FU-based therapies. These agents were therefore incorporated into first- and second-line treatment strategies. The development of targeted agents that are tumor specific with better toxicity profiles than chemotherapeutic agents has widened the spectrum of therapies for this disease. The U.S. Food and Drug Administration (FDA) recently approved two targeted agents for treating mCRC: an antivascular endothelial growth factor monoclonal antibody (mAb), bevacizumab (Avastin; Genentech, Inc., South San Francisco, CA, http://www.gene.com), in combination with first-line 5-FU-based chemotherapy regimens and the human epidermal growth factor receptor (HER-1/EGFR)-targeted mAb cetuximab (Erbitux; ImClone Systems, Inc., New York, NY, http://www.imclone.com) as monotherapy or in combination with irinotecan as second-line therapy in refractory cancer. These newer, more effective agents are improving clinical outcome for patients with mCRC. However, as the number of agents has increased, choosing the most effective treatment strategy has become increasingly complex. This review discusses the role of the individual agents in the treatment of mCRC and identifies the most effective regimens.

Systemic Therapy for Metastatic Colorectal Cancer: Current Options, Current Evidence

Combination chemotherapy regimens including irinotecan and oxaliplatin markedly improve response rate and prolong median survival over fluorouracil with leucovorin (FU/LV), and have supplanted FU/LV as the standard systemic approach for metastatic colorectal cancer. The recent availability of five active chemotherapeutic agents has doubled the median overall survival for metastatic colorectal cancer from 10 to 20 months, and though the optimal strategy for incorporation of all drugs is still unclear, current data support the use of chemotherapy doublets in first-line rather than sequential single-agent therapy. Multidrug regimens increase both response rate and the proportion of patients able to undergo potentially curative resection. In addition, as many as 20% to 30% of patients never receive second-line chemotherapy. When used as single agents, bolus and infusional FU/LV and capecitabine are similarly effective but have differing toxicity. Chemotherapy combinations that incorporate infusion of FU are less toxic and more effective than those using bolus FU dosing. Capecitabine is under study as an alternative dosing method for use in combination regimens; however, the optimal dose has not been defined and final safety and efficacy outcomes are being addressed in ongoing phase II and III investigations. Three combinations have shown excellent first-line efficacy in phase III trials—IFL with bevacizumab, FOLFOX, and FOLFIRI—but neither of these combinations is clearly superior. Sound clinical judgment must continue to guide treatment decisions while we await data regarding the optimal combination and sequence of fluorouracil, irinotecan, oxaliplatin, bevacizumab, and cetuximab.

Assessment of Infusional 5-Fluorouracil Schedule and Dose Intensity: A Southwest Oncology Group and Eastern Cooperative Oncology Group Study

BACKGROUND

Building on results from Southwest Oncology Group trial 8905, this trial was designed to compare low-dose continuous infusion (LDCI) of 5-fluorouracil (5-FU) versus intermittent high-dose infusion (HDI) of 5-FU in disseminated colorectal cancer (CRC) for evidence of survival advantage based on dose intensity. A companion trial was funded to assess molecular parameters associated with fluoropyrimidine response or resistance and toxicity from these treatments.

PATIENTS AND METHODS

Eligibility included histologic diagnosis of disseminated CRC, measurable or evaluable disease, no previous therapy for metastatic disease, performance status of 0-2, and adequate renal, hepatic, cardiac, and hematologic function. Stratification factors were measurable versus evaluable disease, performance status of 0/1 versus 2, presence versus absence of adjuvant therapy, and presence versus absence of previous surgery and enrollment on the companion trial. Patients were randomized to receive (1) LDCI 5-FU 300 mg/m(2) per day for 28 days every 5 weeks or (2) HDI 5-FU 2,600 mg/m(2) for 24 hours each week.

RESULTS

Between April 1995 and May 1999, 730 patients were accrued (LDCI arm, n = 360; HDI arm, n = 370). Of these, 708 eligible patients were assessable for survival and 690 for toxicity. Median survival for both groups was 13 months. Toxicity was mild; < 10% of patients in both arms had grade > 4 events. There were 8 study-related deaths (1%). Less than 10% of patients were enrolled in the companion trial.

CONCLUSIONS

Increasing 5-FU dose intensity yields no survival advantage beyond that achieved with LDCI 5-FU. This study confirms the favorable toxicity profile of infusional 5-FU. Because no preferential benefit was observed for either infusion schedule, the more convenient weekly schedule should be considered for 5-FU-based combination regimens for disseminated CRC.

Phenotype of microsatellite-stable colorectal carcinomas with CpG island methylation

A distinctive pathway of colorectal carcinogenesis termed CpG island methylator phenotype is characterized by extensive DNA methylation in colorectal carcinoma (CRC) cells but not in nonneoplastic mucosa. Many CRCs with CpG island methylator phenotype have methylation of the hMLH1 mismatch repair gene and consequently have high levels of microsatellite instability (MSI-H). MSI-H confers distinctive clinical-pathologic features, but the phenotype of microsatellite-stable CRC with methylation has not been characterized in detail. We therefore examined the clinical-pathologic features of 87 sporadic microsatellite-stable CRCs that had been characterized for methylation of p16, p14, MGMT, hMLH1, MINT1, MINT2, and MINT31. Regression analyses of each clinical-pathologic characteristic were run against the individual and aggregated methylation markers to evaluate and quantify associations. CpG island methylation was associated with right-sided carcinoma (odds ratio = 6.9, P = 0.03). Paucity of gland formation, indicating poor differentiation, was strongly associated with methylation (beta = -42.6, P = 0.0008), as were presence of cribriform glands (beta = 34.3, P = 0.02) and lack of corkscrew/serrated glandular pattern (beta = -32.5, P = 0.03). Our epigenotype-phenotype correlation study shows that microsatellite-stable CRC with CpG island methylation have a distinctive pathologic phenotype with both similarities to and differences from MSI-H tumors.

Colon cancer

Colon cancer is one of the leading tumours in the world and is considered among the big killers, together with lung, prostate and breast cancer. In the recent years very important advances occurred in the field of treatment of this frequent disease: adjuvant chemotherapy was demonstrated to be effective, chiefly in stage III patients, and surgery was optimized in order to achieve the best results with a low morbidity. Several new target-oriented drugs are under evaluation and some of them (cetuximab and bevacizumab) have already exhibited a good activity/efficacy, mainly in combination with chemotherapy. The development of updated recommendations for the best management of these patients is crucial in order to obtain the best results, not only in clinical research but also in everyday practice. This report summarizes the most important achievements in this field and provides the readers useful suggestions for their professional practice.

A phase II trial of FUdR in patients with advanced pancreatic cancer

PURPOSE

This phase II study was conducted to assess the efficacy of fluorodeoxyuridine (FUdR) in patients with metastatic, advanced pancreatic cancer who had no previous chemotherapy.

PATIENTS AND METHODS

Twenty patients were enrolled in this single institution trial. The primary endpoint of this study was the assessment of overall survivorship. The secondary endpoints were to estimate the time to tumor progression and the assessment of toxicity in this cohort of patients. Treatment consisted of FUdR 150 mg/kg dissolved in 500 cc normal saline intravenous infusion over 24 h. Eight weeks of treatment constituted one course of chemotherapy. Tumor measurements were conducted at 8-weekly intervals.

RESULTS

Four patients achieved partial response and 16 patients had stable disease. Median survival of patients treated with FUdR was 11.6 months with a range of 3-16 months. Median progression-free survival was 6 months. Overall, chemotherapy was well tolerated with low incidence of grade 3 or 4 toxicity.

CONCLUSIONS

Systemic chemotherapy with high dose FUdR administered on a weekly schedule has led to encouraging survival outcomes and improved quality of life as compared to previous phase II single agent chemotherapeutic trials.

Weekly gemcitabine plus 24-h infusion of high-dose 5-fluorouracil/leucovorin for locally advanced or metastatic carcinoma of the biliary tract

Both gemcitabine and weekly 24-h infusion of high-dose 5-fluorouracil/leucovorin (HDFL) have shown promising antitumour activity for patients with locally advanced or metastatic carcinoma of the biliary tract (CBT). From April 1999 through December 2002, 30 patients with inoperable CBT were treated with gemcitabine 800 mg m⁻², intravenous infusion for 30 min, followed by 5-FU, 2000 mg m⁻² and leucovorin, 300 mg m⁻², intravenous infusion for 24 h, on day 1, 8 and 15, every 4 weeks. A total of 166 cycles were given (median of four cycles per patient, range 1–24 cycles). Response was evaluable in 28 patients and toxicity in 29 patients. Partial response was obtained in six patients, stable disease in 13, while progressive disease occurred in nine. The objective response rate was 21.4% (95% CI: 5.2–37.6%). The most common grade 3 or 4 toxicity was infection (nine patients). Other types of grade 3 or 4 toxicity included leucopenia (four patients), thrombocytopenia (three patients), anaemia (three patients), nausea/vomiting (two patients) and elevation of liver transaminases (three patients). As of 30 September 2003, the median progression-free survival was 3.7 months (95% CI: 2.8–4.6 months) and the median overall survival was 4.7 months (95% CI: 0.8–8.6 months). Our data suggest that weekly gemcitabine plus HDFL is modestly active with acceptable treatment-related toxicity for patients with advanced CBT.

MAX2--a convenient index to estimate the average per patient risk for chemotherapy toxicity; validation in ECOG trials

Cancer patients, especially the elderly, present with a highly variable susceptibility to toxicity from chemotherapy. To estimate correctly a patient's risk for toxicity, both the average toxicity of a chemotherapy regimen and patient-related variables need to be assessed. However, treatment toxicities are typically reported item by item, not summarised per patient. We tested an index derived from a pilot study, the MAX2, on the ECOG database. Studies including 20 or more patients aged 70 years and older per arm were selected. Four studies were identified, representing 2526 patients, 410 (16%) being elderly. The association of the MAX2 index with the per patient incidence of grade 4 haematological and/or grade 3 or 4 non-haematological toxicity was highly significant, both for the overall group and for the elderly subgroup. The MAX2 index is a convenient and reproducible way of comparing the average per patient risk for toxicity from chemotherapy across several regimens.