A phase III study of 5-fluorouracil versus 5-fluorouracil plus interferon alpha 2b versus 5-fluorouracil plus leucovorin in patients with advanced colorectal cancer: a Hellenic Cooperative Oncology Group (HeCOG) study

Dysregulation of systemic immunity in colorectal cancer and its clinical applications as biomarkers and therapeutics

The immune system plays critical roles in the initiation and progression of colorectal cancer (CRC), and the majority of studies have focused on immune perturbations within the tumor microenvironment. In recent years, systemic immunity, which mainly occurs in the periphery, has attracted much attention. In CRC, both the tumor itself and treatments have extensive effects on systemic immunity, characterized by alterations in circulating cytokines and immune cells. In addition, intact systemic immunity is critical for the efficacy of therapies for CRC, especially immunotherapy. Therefore, various strategies aimed at alleviating the detrimental effects of traditional therapies or directly harnessing the components of systemic immunity for CRC treatment have been developed. However, whether these improvements can translate to survival benefits requires further study. This review aims to comprehensively outline the current knowledge of systemic immunity in CRC.

Combination adjuvant chemotherapy with targeted drugs for treatment of colorectal cancer: A network meta-analysis

Colorectal cancer (CRC) is one of the most fatal diseases in the world. The efficacy of present chemotherapy treatments are limited and the addition of targeted drugs have been put into practice. However, the preferred treatments among adjuvant chemotherapies still remain controversial and uncertain. To evaluate the efficacy of different adjuvant chemotherapies combined with or without targeted drugs to determine the optimal treatment for patients with CRC in clinical practice. PubMed and Embase were searched for eligible articles and only randomized controlled trials (RCTs) were included. R (Version 3.2.5) software was utilized to conduct the Bayesian network meta-analysis (NMA). Outcomes including overall survival (OS) and progression-free survival (PFS) were displayed using hazard ratios. And the rank probabilities of each treatment were evaluated using the surface under cumulative ranking curve. A total of 75 RCTs published after 1997 were included in the data analysis. Overall, FOLFIRI+ cetuximab was found to be the most effective treatment in terms of long-term survival and FOLFOX was the most effective pure chemotherapy treatment. The addition of targeted drugs will greatly improve the efficacy of chemotherapy. Targeted drug cetuximab combined with the chemotherapy regiment FOLFIRI is the preferable treatment for patients with CRC in clinical practice.

Cancer immunotherapy

Cancer immunotherapy consists of approaches that modify the host immune system, and/or the utilization of components of the immune system, as cancer treatment. During the past 25 years, 17 immunologic products have received regulatory approval based on anticancer activity as single agents and/or in combination with chemotherapy. These include the nonspecific immune stimulants BCG and levamisole; the cytokines interferon-α and interleukin-2; the monoclonal antibodies rituximab, ofatumumab, alemtuzumab, trastuzumab, bevacizumab, cetuximab, and panitumumab; the radiolabeled antibodies Y-90 ibritumomab tiuxetan and I-131 tositumomab; the immunotoxins denileukin diftitox and gemtuzumab ozogamicin; nonmyeloablative allogeneic transplants with donor lymphocyte infusions; and the anti-prostate cancer cell-based therapy sipuleucel-T. All but two of these products are still regularly used to treat various B- and T-cell malignancies, and numerous solid tumors, including breast, lung, colorectal, prostate, melanoma, kidney, glioblastoma, bladder, and head and neck. Positive randomized trials have recently been reported for idiotype vaccines in lymphoma and a peptide vaccine in melanoma. The anti-CTLA-4 monoclonal antibody ipilumumab, which blocks regulatory T-cells, is expected to receive regulatory approval in the near future, based on a randomized trial in melanoma. As the fourth modality of cancer treatment, biotherapy/immunotherapy is an increasingly important component of the anticancer armamentarium.

The impact of chemotherapy on overall survival and quality of life of patients with metastatic colorectal cancer: a review of phase III trials

The treatment aims for advanced colorectal cancer (ACRC) patients are to prolong overall survival and to improve or maintain quality of life. Phase III studies published between 1997 and 2006 comparing different first or subsequent lines of treatment regimens were collected in order to evaluate the impact of these regimens on the overall survival and quality of life of ACRC patients. Our review shows that a first-line polychemotherapy regimen including oxaliplatin or irinotecan, in comparison with monochemotherapy, can improve overall survival. Second-line therapy and/or a cross-over between the first-line treatment arms can further modify the disease course. Hence, from the very beginning the treatment of ACRC patients must embrace a strategic approach taking into account all new agents available. Quality of life (QoL) was assessed in 52.3% of the first-line studies, while this was done in the whole group of studies evaluating pre-treated patients. QoL appears to be unrelated to the toxicity profile.

Influence of chemotherapeutic agents and cytokines on the expression of 5-fluorouracil-associated enzymes in human colon cancer cell lines

BACKGROUND

Several studies have demonstrated that intratumoral expression of catabolizing and anabolizing enzymes for 5-fluorouracil (5-FU) is important in the response of cancers to 5-FU-based chemotherapy. We investigated the influence of other chemotherapeutic agents or cytokines, which are often administered for enhancing the efficacy of 5-FU, on the tumoral expression of 5-FU-associated enzymes, i.e., dihydropyrimidine dehydrogenase (DPD), thymidylate synthase (TS), orotate phosphoribosyl transferase (OPRT), and thymidine phosphorylase (TP).

METHODS

Human colon cancer cell lines (HT-29, Caco-2, and DLD-1) were incubated with 5-FU and with 5-FU combined with cisplatin, camptothecin, paclitaxel, mitomycin C, interferon, or TNF-related apoptosis-inducing ligand. mRNA expression of 5-FU-associated enzymes was assessed by real-time PCR. Activity of each enzyme and intracellular 5-FU accumulation after incubation with such agents were also evaluated.

RESULTS

Each agent had a synergistic effect on the cytotoxicity of 5-FU. All chemotherapeutic agents other than cytokines induced marked alteration of the mRNA expression profile of 5-FU-associated enzymes; depression of DPD, elevation of TS, and slight suppression of OPRT and TP. In accordance with mRNA expression, enzyme activity of DPD was significantly depressed by such agents. Furthermore, although 5-FU itself increased DPD mRNA expression, a mechanism considered to be related to the acquisition of 5-FU resistance, the addition of cisplatin or camptothecin significantly inhibited the 5-FU-induced elevation of DPD.

CONCLUSIONS

5-FU-associated enzymes in colon cancer cells were greatly influenced by various chemotherapeutic agents; in particular, DPD expression was depressed. These results appear important in planning chemotherapy and also in understanding the development of adverse effects of 5-FU.

Modulation of fluorouracil by leucovorin in patients with advanced colorectal cancer: an updated meta-analysis

PURPOSE

The modulation of fluorouracil (FU) by folinic acid (leucovorin [LV]) has been shown to be effective in terms of tumor response rate in patients with advanced colorectal cancer, but a meta-analysis of nine trials previously published by our group failed to demonstrate a statistically significant survival difference between FU and FU-LV. We present an update of the meta-analysis, with a longer follow-up and the inclusion of 10 newer trials.

PATIENTS AND METHODS

Analyses are based on individual data from 3,300 patients randomized in 19 trials on an intent-to-treat basis. Two trials had multiple comparisons, leading to a total of 21 pair-wise comparisons. FU doses were similar in both arms in 10 pair-wise comparisons, 15% to 33% higher in the FU-alone arm in six comparisons, and more than 66% higher in five comparisons.

RESULTS

Overall analysis showed a two-fold increase in tumor response rates (11% for FU-LV v 21% for FU-LV v 11% for FU [corrected] alone; odds ratio, 0.53; 95% CI, 0.44 to 0.63; P <.0001) and a small but statistically significant overall survival benefit for FU-LV over FU alone (median survival, 11.7 v 10.5 months, respectively; hazards ratio, 0.90; 95% CI, 0.87 to 0.94; P =.004), which were primarily seen in the first year. We observed a significant interaction between treatment benefit and dose of FU, with tumor response and overall survival advantages of FU-LV over FU-alone being restricted to trials in which a similar dose of FU was prescribed in both arms.

CONCLUSION

This updated analysis demonstrates, on a large data set, that FU-LV improves both response rate and overall survival compared with FU alone and that this benefit is consistent across various prognostic factors.

A Phase II Study with CPT-11 Plus Leucovorin and Bolus IV 5-Fluorouracil in Patients with Advanced Colorectal Carcinoma

Standard chemotherapy in advanced colorectal carcinoma (CRC) has not yet been established. The present study was conducted to assess the efficacy and toxicity profile of CPT-11, leucovorin (LV), and bolus 5-fluorouracil (5-FU) in a weekly schedule. Fifty-five patients were entered with no prior chemotherapy for advanced disease or adjuvant treatment ended at least 6 months preceding study entry, and 45 were assessable for response. Patients were treated with CPT-11 80 mg/m2 (7 patients) or 70 mg/m2 (48 patients). After completion of CPT-11 infusion, LV 200 mg/m2 was administered over 2 hr followed immediately by 5-FU 450 mg/m2, IV bolus, weekly for 6 weeks followed by a 2-week rest period. Treatment was continued for four cycles. Because of grade 3 and 4 diarrhea in four of the first seven patients, the study was amended to reduce the starting dose of CPT-11 from 80 to 70 mg/m2 weekly. Four complete and 10 partial responses were observed (response rate: 25.5%), the median time to progression (TTP) was 7.7 months, 1-year survival rate was 62.3%, and the median overall survival was 15.0 months. Grade 3 and 4 diarrhea occurred in seven patients (12.7%), four of them treated with CPT-11 80 mg/m2. Grade 3 myelotoxicity occurred in five patients (9.0%). Toxic death because of diarrhea, neutropenia, bacteremia, and sepsis occurred in a patient treated with CPT-11 80 mg/m2. Our results confirm the efficacy of CPT-11, LV, and 5-FU in a weekly schedule in patients with advanced CRC. Further studies are needed to compare the present regimen with higher doses of CPT-11 with LV plus different schedules of 5-FU administration in the treatment of metastatic CRC.