Risk factors for thrombotic events in giant cell arteritis and polymyalgia rheumatica

BACKGROUND: FOLFOX2, a bimonthly regimen of high-dose leucovorin (LV), 48-hour continuous infusion of 5-fluorouracil (5-FU) (LV-5-FU) and oxaliplatin (100 mg/m2) produced a high response rate (46%; 95% confidence interval (95% CI): 31%-60%) in 5-FU pre-treated patients with metastatic colorectal cancer. In this phase II study, pre-treated patients were given a lower dose of oxaliplatin to reduce the toxic effects of the regimen. PATIENTS AND METHODS: Thirty patients with advanced colorectal adenocarcinoma and progression while receiving bimonthly LV-5-FU (LV: 500 mg/m2, 5-FU: 1.5-2 g/m2/22 hours, days 1-2, every two weeks), were given the same LV-5-FU schedule with the addition of oxaliplatin (85 mg/m2) every two weeks (FOLFOX3). RESULTS: The main toxic effects were peripheral neuropathy (90%) with four severe sensitive neuropathies (WHO grade 2: 13%). The response rate was 20% (95% CI: 8%-39%). Median progression-free survival was 26 weeks, median survival was 57 weeks from the start of FOLFOX3 and median duration of the response was 37 weeks. CONCLUSIONS: Results obtained with FOLFOX3 confirmed the synergy between oxaliplatin and 5-FU in 5-FU-resistant metastatic colorectal cancer. However, the response rate seems to be lower than that obtained with FOLFOX2. Further studies to determine the best oxaliplatin dose intensity are in progress.     

A phase II trial of interleukin-2 and interferon-alpha in the treatment of metastatic colorectal carcinoma

A total of 29 patients with stage IV colorectal cancer were entered into a phase II trial of bolus interleukin-2 (IL-2) and interferon-alpha (IFN alpha) (3 x 10(6) U/m2 of each cytokine given i.v. q8h x 15 doses and repeated in 2 weeks). Immunologic parameters measured on isolated peripheral blood lymphocytes revealed increased activated T cells with upregulated natural killer and lymphokine-activated killer activity. Among 24 evaluable patients, there were 4 partial responses (17%) of short duration ( < or = 6 months). Three of the responding patients had been refractory to prior chemotherapy. Overall median survival in the 24 evaluable patients was 18.5 months. Therapy necessitated an inpatient setting, with the most common toxicities being hypotension, hepatic insufficiency, fever, hypocalcemia, nausea/vomiting, and renal insufficiency. There were two treatment-related deaths. Because neither IL-2 nor IFN alpha alone has significant activity against colorectal cancer, the responses observed in this study suggest a potential synergistic effect between the two cytokines. However, the toxicity and short duration of response without survival benefit do not support the routine use of this regimen as a therapeutic modality for this tumor histology.     

Interleukin-2-activated killer cell activity in colorectal tumor patients: evaluation of in vitro effects by prothymosin alpha1

The effects of prothymosin alpha1 (Pro alpha1) in combination with interleukin-2 (IL-2) on peripheral blood lymphocytes from 50 colorectal tumor patients at different stages were studied with respect to immunocytotoxicity, adhesion to cultured SW620 colon carcinoma cells, secretion of cytokines and expression of adhesion and surface marker molecules. On average, the patients showed lower natural killer (NK) cell activity than healthy donors, which was associated with a lower adhesion capacity to the tumor target cells. The NK cell activity of the patients was inversely related to the tumor stage. The generation of lymphokine(IL-2)-activated killer (LAK) cell activity was found to be comparable on lymphocytes from healthy individuals and patients and was not correlated to tumor stage. Pro alpha1 stimulated patients' LAK cell activity only, primarily at the early stage (Dukes A/B). The Pro alpha1 effect was associated with an increased adhesion of lymphocytes to tumor target cells and an increased secretion of the deficient IL-2-induced IFN gamma secretion. No significant effects on the low level of TNF alpha secretion was noted. By flow cytometry, Pro alpha1 in combination with IL-2 augmented the expression of the NK cell markers CD56, CD16/56, the subset CD3/16/56 and CD25 on lymphocytes of the patients. In contrast, Pro alpha1 was equally effective by increasing the expression of CD18 and CD11a on lymphocytes from the patients and from normal controls. In conclusion, Pro alpha1, in combination with IL-2, can partially normalize lymphocyte deficiencies of colon cancer patients in vitro. This potential might provide an experimental basis for applying Pro alpha1 or related thymic peptides in selected immunotherapies against colorectal tumors.     

Abnormalities of CD45 isoform expression in HIV infection

Systemic chemotherapy with 5-fluorouracil (5-FU) has been the mainstay of treatment for patients with metastatic colorectal carcinoma. Administering the drug in a continuous low-dose schedule has produced better result than bolus therapy. Resistance to short-pulse treatment can also be overcome by prolonged exposure. Recent studies suggest the feasibility of biomodulation of 5-FU with recombinant interferon (rIFN alpha-2a) with improved response. Sixteen patients were treated with continuous 5-FU 250 mg/m2 and rIFN alpha-2a 10 x 10(6) u thrice weekly for a maximum of 24 weeks. Five of them had received bolus 5-FU previously. Nine (82%) of the chemonaive group and 1 (20%) previously treated patient had partial response. The median duration of response was 7 months. Grade II to III mucositis were seen in 44% of the patients and 2 patients developed neurological complications. Although the overall response appeared encouraging, the incidence of toxicity was high. In the absence of further phase III studies, rIFN alpha-2a biomodulation of 5-FU cannot be regarded as standard treatment for patients with metastatic colorectal carcinoma.     

Fluorouracil and leucovorin with or without interferon alfa-2b in advanced colorectal cancer: analysis of a prospective randomized phase III trial. Hellenic Cooperative Oncology Group

PURPOSE: To investigate if double modulation of fluorouracil (5-FU) with leucovorin (folinic acid [FA]) and interferon alfa-2b (IFN 2b) improves responses and survival in comparison to single modulation of 5-FU with FA. PATIENTS AND METHODS: One hundred six patients with histologically confirmed advanced colorectal cancer, measurable disease, and without previous chemotherapy were prospectively randomized into two groups. Patients in group A received 5-FU 450 mg/m2 as an intravenous bolus in the midinfusion of FA weekly. FA was given at a dose of 200 mg/m2 in 500 mL 0.9% normal saline solution in 2-hour infusion. Patients in group B received exactly the same regimen plus IFN 2b 5 million units subcutaneously three times weekly. RESULTS: All patients were well balanced in both groups regarding age, sex, performance status, number, and site of metastasis. One hundred two patients were assessable. All patients have died. There was no difference in response between the two groups (7.8% v 9.8%). Median survival was 10.1 months in group A, and 7.2 months in group B (P = .00189). Median time to progression was 8.4 and 5.2 months, respectively (P = .00196). Overall, better performance status and older age had a positive impact on survival. Toxicity was the most important and catastrophic aspect of this study. Patients who received IFN 2b had significantly worse anemia, neutropenia, diarrhea, anorexia, weight loss, flu-like syndrome, and psychological reactions. CONCLUSION: Based on this final analysis, the addition of IFN 2b to the combination of 5-FU and FA enhances toxicity and contributes to decreased survival.     

Combination chemotherapy of continuous infusion 5-fluorouracil and daily low-dose cisplatin in advanced gastrointestinal and lung adenocarcinoma

Continuous intravenous infusion (c.v.i.) of 5-fluorouracil (5-FU) plus daily low-dose cisplatin (CDDP) was evaluated in 45 patients with advanced and recurrent unresected colorectal, lung, gastric and pancreatic adenocarcinoma. 5-FU was given at a dose of 320 mg/m2/day, c.v.i. for 4 weeks, and CDDP between 3.5 to 7 mg/m2/day, infused for one hour five times a week for 4 weeks. Patients received 1 to 3 cycles of treatment (average 1.5 cycle). Pancreatic cancer cases needed longer treatment periods (2.25 cycles). The response rate of colorectal cancer cases was 57.7% (15/26), pancreas cancer 40%, gastric cancer 62.5%, and lung cancer 66.7%. The overall response rate was 57.8%. No severe side effects occurred in any of these cases. These data indicate that this combination 5-FU + daily low-dose CDDP chemotherapy is effective in the treatment of advanced gastrointestinal and lung adenocarcinoma.     

Twelve-year experience with the 19 mm Carpentier-Edwards pericardial aortic valve

BACKGROUND: The purpose of the present study was to investigate the therapeutic effectiveness of interleukin-2 (IL-2) and interferon (IFN), either alone or in combination, in comparable groups of patients affected by advanced renal cell carcinoma (RCC). PATIENTS AND METHODS: In order to limit selection biases, treatment was allocated on a random basis. Patients randomized to IL-2 alone were scheduled to receive eight rlL-2 24-hour i.v. infusion cycles, days 1 to 4, at a daily dose of 18 x 10(6) lU/m2 for a total of 25 weeks. Patients randomized to IFN alone were scheduled to receive rIFN-alpha at a daily dose of 6 x 10(6) IU/m2, days 1, 3 and 5, every week for a total of 52 weeks. Patients randomized to the combination of IFN and IL-2 were given the same drugs at the same daily doses for a total of 24 weeks. Drug dose was modified according to toxicity. RESULTS: Twenty-three percent (95% CI:+/-17.5) of patients treated with IL-2 alone showed an objective response to treatment (9% CR). The corresponding figures in patients treated with IFN alone or IFN plus IL-2 were 9% (95% CI:+/-11.9) and 9% (95% CI:+/-11.9), respectively. Complete responses were observed only in patients treated with IL-2. The median duration of response in the IL-2 arm was 18 months (range, 9.5-24). The duration of the two responses achieved by IFN alone was seven and nine months, respectively. The corresponding figures in the two patients responding to the combination of IFN with IL-2 were 19 and 27 months, respectively. Total IL-2 dose appeared to be a major predictor of response. Only a minority of patients experienced grade 3-4 toxicity, the incidence being higher in those treated with IL-2 or IL-2 plus IFN. CONCLUSIONS: Neither IFN nor IL-2 or the combination of the two appear to be very active in patients with advanced RCC, even when trial entry was restricted to patients with relatively indolent disease. This stresses the need for the development of new approaches.     

Long-term weekly treatment of colorectal metastatic cancer with fluorouracil and leucovorin: results of a multicentric prospective trial of fluorouracil dosage optimization by pharmacokinetic monitoring in 152 patients

PURPOSE: A relationship between fluorouracil (5-FU) dose and response has been previously shown in advanced colorectal cancer. In a previous study with 5-FU stepwise dose escalation in a weekly regimen, and pharmacokinetic monitoring, we defined a therapeutic range for 5-FU plasma levels: 2,000 to 3,000 microg/L (area under the concentration-time curve at 0 to 8 hours [AUC0-8], 16 to 24 mg x h/L). The current study investigated 5-FU therapeutic intensification with individual dose adjustment in a multicentric phase II prospective trial. PATIENTS AND METHODS: Weekly high-dose 5-FU was administered by 8-hour infusion with 400 mg/m2 leucovorin. The initial dose of 5-FU (1,300 mg/m2) was adapted weekly according to 5-FU plasma levels, to reach the therapeutic range previously determined. RESULTS: A total of 152 patients entered the study from December 1991 to December 1994: 117 patients with measurable metastatic disease and 35 with assessable disease. Toxicity was mainly diarrhea (39%, with 5% grade 3) and hand-foot syndrome (30%, with 2% grade 3). Among 117 patients with measurable disease, 18 had a complete response (CR), 48 a partial response (PR), 35 a minor response (MR) and stable disease (SD), and 16 progressive disease (PD). Median overall survival time was 19 months. The 5-FU therapeutic plasma range was rapidly reached with a variable 5-FU dose in the patient population: mean, 1,803 +/- 386 mg/m2/wk (range, 950 to 3,396). Thirteen patients were immediately in the toxic zone, whereas 51 required a > or = 50% dose increase. CONCLUSION: Individual 5-FU dose adjustment with pharmacokinetic monitoring provided a high survival rate and percentage of responses, with good tolerance.     

Adjuvant 5-fluorouracil and leucovorin with or without interferon alfa-2a in colon carcinoma: National Surgical Adjuvant Breast and Bowel Project protocol C-05

BACKGROUND: National Surgical Adjuvant Breast and Bowel Project (NSABP) protocol C-03 showed a benefit from leucovorin (LV)-modulated 5-fluorouracil (5-FU) adjuvant therapy (5-FU + LV) in patients with Dukes' stage B or C carcinoma of the colon. Preclinical and clinical phase I/II data suggested that interferon alfa-2a (IFN) enhanced the efficacy of 5-FU therapy. Accordingly, in NSABP protocol C-05, the addition of recombinant IFN to 5-FU + LV adjuvant therapy was evaluated. METHODS: Data are presented for 2176 patients with Dukes' stage B or C cancer entered onto protocol C-05 during the period from October 1991 through February 1994. Individuals with an Eastern Cooperative Oncology Group performance status of 0-2 (ranges from fully active to ambulatory and capable of self-care but unable to work), a life expectancy of at least 10 years, and curative resection were stratified by sex, disease stage, and number of involved lymph nodes and were randomly assigned to receive either 5-FU + LV or 5-FU + LV + IFN; the mean time on the study as of June 30, 1997, was 54 months. All statistical tests were two-sided. RESULTS: There was no statistically significant difference in either disease-free survival (5-FU + LV, 69%; 5-FU + LV + IFN, 70%) or overall survival (5-FU + LV, 80%; 5-FU + LV + IFN, 81%) at 4 years of follow-up. Toxic effects of grade 3 or higher were observed in 61.8% of subjects in the group treated with 5-FU + LV and in 72.1% of subjects in the group treated with 5-FU + LV + IFN; fewer patients in the latter group completed protocol-mandated 5-FU + LV therapy than in the former group (77.1% versus 88.5%). CONCLUSION: The addition of IFN to 5-FU + LV adjuvant therapy confers no statistically significant benefit, but it does increase toxicity.     

Low-dose cisplatin-5-fluorouracil prevents postoperative suppression of natural killer cell activity in patients with gastrointestinal cancer

BACKGROUND: The effect of administering low-dose cisplatin (CDDP)-5-fluorouracil (5-FU) postoperatively on the activity of the immune system is not known. To clarify the effect on natural killer (NK) cell activity of treatment with low-dose CDDP-5-FU, we compared NK cell activity after surgery for gastrointestinal cancer in patients treated with low-dose CDDP-5-FU, a bolus dose of mitomycin C (MMC) or no anticancer drug. METHODS: Sixty-two patients consisted of three groups: low-dose CDDP-5-FU (n = 15), MMC (n = 20) and no-drug (n = 27). Chemotherapy was initiated immediately after surgery. NK cell activity was measured on the day before surgery (pre-op) and on postoperative days 7 (POD7) and 21 (POD21). RESULTS: The NK cell activities of the CDDP-5-FU group were 37.7% at pre-op, 36.1% on POD7 and 33.6% on POD21. However, the NK cell activities in the no-drug and MMC groups were significantly decreased on POD7 (from 36.6 to 24.8% and from 31.4 to 16.6%, respectively). The NK cell activity in the MMC group remained depressed on POD21 (18.6%) whereas that in the no-drug group recovered (31.6%). CONCLUSIONS: Consecutive administration of low-dose CDDP-5-FU appears to be useful as postoperative adjuvant chemotherapy because of its preventive effect on NK cell suppression after surgery.     

Daily subcutaneous injection of low-dose interleukin 2 expands natural killer cells in vivo without significant toxicity

We aimed to determine the toxicity and immunological effects of daily s.c. administered low-dose interleukin (IL) 2. Adult cancer patients received a single daily s.c. injection of IL-2 as outpatients for 90 consecutive days. Cohorts of four to nine patients were treated at escalating IL-2 dose levels until the maximum tolerated dose (MTD) was defined. Peripheral blood mononuclear cell phenotyping, IL-2 serum levels, and the presence of anti-IL-2 antibodies were investigated. Thirty-eight patients were treated at seven IL-2 dose levels ranging from 0.4 to 1.75 million International Units (mIU)/m2 daily. The MTD was 1.25 mIU/m2, with constitutional side effects, vomiting, and hyperglycemia dose limiting. Severe toxicity did not occur at or below the MTD, although mild local skin reaction and mild constitutional side effects were common. Objective tumor regressions were not observed during this Phase I trial. Low-dose IL-2 resulted in natural killer (NK) cell (CD3(-) CD56(+)) expansion at all dose levels. This effect was dose dependent (P < 0.01), ranging from a 154 to 530% increase over baseline. Peak NK levels were achieved at 6-8 weeks and sustained through 12 weeks of therapy. As predicted by in vitro studies of IL-2 receptor structure-activity relationships, the subset of NK cells that constitutively express high-affinity IL-2 receptors (CD3(-)CD56(bright+)) showed more profound dose-dependent expansion, with increases ranging from 368 to 2763% (P = 0.015). NK expansion occurred at peak IL-2 levels <10 pM (2.3 IU/ml). Three patients developed nonneutralizing anti-IL-2 antibodies. Thus, we concluded that selective expansion of NK cells may be achieved in vivo with daily s.c. injections of low-dose IL-2 with minimal toxicity.     

In vitro percutaneous penetration through hairless rat skin: influence of temperature, vehicle and penetration enhancers

From February 1995 through October 1996, 25 patients with metastatic colorectal cancer showing a clinical resistance to 5-fluorouracil (5-FU) entered this study. Thirteen received oxaliplatin alone and 12 received it in combination with 5-FU. Oxaliplatin was administered at 130 mg/m2 over a 2-hour infusion every 3 weeks, alone or added either to 5-FU as a continuous infusion at 200 mg/m2 to 300 mg/m2 (six patients) or to a 5-FU bolus, 375 mg/m2, plus leucovorin, 100 mg/m2, daily for 5 days every 3 weeks (6 patients). Eighty-six of 98 administered cycles were evaluable for toxicity (47 for oxaliplatin plus 5-FU and 39 for oxaliplatin alone). Hematologic toxicity was mild, occurring as grade 2 leukopenia in 23% of the cycles of 5-FU and oxaliplatin and in 5% of the cycles of oxaliplatin alone. The most common toxicity was neurologic (grade 1 to 2 in 60%-6% of the cycles of the combination, respectively, and 68%-10% of oxaliplatin given alone) as hand-foot paresthesia or hypersensitivity to cold. No grade 4 toxicity was reported and only three patients in the 5-FU group developed grade 3 diarrhea. Grade 2 nausea and vomiting occurred in 33% of the cycles when both drugs were given and in 15% when oxaliplatin was administered alone. The combination of oxaliplatin and 5-FU induced four partial remissions (33%; 95% confidence interval, 6%-60%), whereas eight patients of the whole group had stable disease. No response occurred when oxaliplatin was administered as a single agent. The results of this study confirm the antitumor activity of oxaliplatin when added to 5-FU in patients who have metastatic colorectal cancer previously refractory to 5-FU. The possible therapeutic synergy with 5-FU was not accompanied by increased toxicity.     

Anti-glomerular basement membrane (GBM)-antibody-mediated disease with normal renal function

The purpose of this study was to compare the objective response rate, duration of remission, and survival of 5-fluorouracil (5-FU) versus those of 5-FU plus levamisole in metastatic colorectal cancer using the same dose and schedule of these agents as in the North Central Cancer Treatment Group and intergroup studies of adjuvant therapy. Patients with no prior history of chemotherapy for metastatic disease were entered on this Hoosier Oncology Group randomized Phase III trial. Patients were stratified by Karnofsky performance status and presence or absence of liver metastases. They were randomized to receive 450 mg/m2 5-FU i.v. for 5 days followed by 15 mg/kg i.v. weekly (arm 1) or the same dose of 5-FU plus levamisole 50 mg p.o. every 8 h for 3 days every 2 weeks (arm 2). The duration of treatment for both arms was 26 weeks. From April 1990 to March 1995, 199 patients were entered. One hundred eighty-two patients, 91 in each arm, were fully evaluable. The response rates were 12% on arm 1 and 13% on arm 2. The median duration of response was 18 weeks on both arms. The median survival was 48 weeks on arm 1 and 41 weeks on arm 2 (P = 0.20). This study failed to show any improvement in survival, response, or duration of remission with the addition of levamisole to 5-FU in the treatment of metastatic colorectal cancer.     

Effects of retinoic acid on the endoderm in Xenopus embryos

Natural killer (NK) cells may be expanded in vivo with a prolonged course of daily subcutaneous interleukin-2 (IL-2). However, cellular activation requires higher concentrations of IL-2 than are achieved with low-dose therapy. The objective of the current trial was to determine the toxicity and immunological effects of periodic subcutaneous intermediate-dose IL-2 pulses in patients receiving daily low-dose therapy. A group of 19 patients were treated with daily subcutaneous low-dose IL-2 at 1.25 x 10(6) International Units (1.25 MIU) m(-2) day(-1). After 4-6 weeks, patients received escalating 3-day intermediate-dose IL-2 pulses administered as single daily subcutaneous injections, repeated at 2-week intervals. The maximum tolerated pulse dose was 15 MIU m(-2) day(-1), with transient hypotension, fatigue, and nausea/vomiting dose-limiting. Subcutaneous IL-2 resulted in in vivo expansion of CD56+ NK cells (796+/-210%) and CD56bright natural killer (NK) cells (3247+/-1382%). Expanded NK cells coexpressed CD16, and showed lymphokine-activated killer activity and antibody-dependent cellular cytotoxicity in vitro. Intermediate-dose pulsing resulted in serum IL-2 concentrations above 100 pM. Cellular activation was suggested by rapid margination of NK cells following pulsing, coincident with peak IL-2 levels, with return to baseline by 24 h. In.addition, interferon gamma production in response to lipopolysaccharide was augmented. Subcutaneous daily low-dose IL-2 with intermediate-dose pulsing is a well-tolerated outpatient regimen that results in in vivo expansion and potential activation of NK cells, with possible application in the treatment of malignancy and immunodeficiency.     

Clinical evidence that the human monoclonal anti-idiotypic antibody 105AD7, delays tumor growth by stimulating anti-tumor T-cell responses

A human monoclonal anti-idiotypic antibody, 105AD7, which mimics a colorectal tumor associated antigen, 791Tgp72, has been developed. A Phase I trial in advanced colorectal cancer patients showed that 105AD7 therapy was nontoxic and that immunised patients had prolonged survival when compared to a contemporary group of patients treated in the same center. There is accumulating clinical evidence that 105AD7 delays tumor growth by stimulating anti-tumor T-cell responses. Stimulation of helper T-cells was exemplified in the phase I study as 105AD7 immunized patients showed antigen specific T-cell blastogenesis responses and enhanced IL-2 production. Further evidence was obtained from a new clinical study in which colorectal cancer patients were immunized prior to tumor resection. Immune infiltrating cells were analysed by immunohistochemistry and effector cell function was studied in immune cells from peripheral blood and tumor draining lymph nodes. Both activated CD4 and natural killer (NK) cells were observed at the tumor site, which is of interest as NK cells are rarely found in colorectal tumors. Effector studies confirmed that NK activity was enhanced in 3/6 patients. Increased autologous tumor killing was also found in 3/4 patients and accumulation of CD8RO cells following 105AD7 immunization also suggested that CD8 T cells were being stimulated.     

Arterial infusion chemotherapy of 5-FU and leucovorin for patients with liver metastases from colorectal cancer

Fifteen patients with liver metastases from colorectal cancer were treated by arterial infusion of 5-FU and leucovorin. Two regimens were performed. One was weekly bolus infusion of leucovorin following bolus infusion of 5-FU (bolus group), the other was 5 days continuous infusion of 5-FU and leucovorin in 3 weeks (continuous group). One PR was obtained both in the bolus group and in the continuous groups. The objective response rate was 11% in the bolus group and 20% in the continuous group. The one- and 2-year survival rates for these patients were 40% and 0% in the bolus group, and 80% and 60% in the continuous group, respectively. These results suggest that continuous arterial infusion of 5-FU and leucovorin was more effective than individual bolus arterial infusion of leucovorin and 5-FU for patients with liver metastases from colorectal cancer.     

Comparison of 5-fluoro-2'-deoxyuridine with 5-fluorouracil and their role in the treatment of colorectal cancer

Despite more than 30 years of intensive studies on new drugs against advanced colorectal cancer, the fluoropyrimidines remain the drugs of choice for systemic treatment and for hepatic artery infusion (HAI). This overview describes new developments in advanced colorectal cancer chemotherapy, providing a rationale for more effective use of the fluoropyrimidines, with biochemical modulation, scheduling or by revealing biochemical mechanisms of action that correlate with antitumour activity. In human colorectal cancer cell lines and various animal tumour model systems 5-fluoro-2'-deoxyuridine (FdUrd) is more effective than 5-fluorouracil (5-FU). Comparably, FdUrd's modulation by leucovorin (LV) is more potent than 5-FU. In animal studies it is shown that intermittent high-bolus administration of FdUrd generates better antitumour activity, compared with equal toxic doses or any other schedule of 5-FU. These effects are related to prolonged-thymidylate synthase (TS) inhibition and the prevention of TS induction, rather than RNA incorporation. Preclinical studies with modulators such as N-phosphonacetyl-L-aspartate (PALA), WR-2721, mitomycin C and platinum derivatives provide a rationale for clinical use in the future. The first choice systemic chemotherapy of patients with advanced colorectal cancer remains 5-FU combined with LV. Some improvement in therapeutic efficacy has been achieved with locoregional HAI. In randomised studies HAI FdUrd improves the quality of life and survival as compared with optimal systemic therapy. Chronomodulation decreases toxicity, allowing dose intensification, while modulators such as LV or dexamethasone increase survival of patients treated with HAI FdUrd to 86% after 1 year. In conclusion, the clinical use of FdUrd has not been fully explored. Intermittent high-dose FdUrd, chronomodulation together with the use of modulators or drugs focused on prolonged TS inhibition, should be studied in large randomised studies.     

Adjuvant chemotherapy in colorectal cancer with high-dose leucovorin and fluorouracil: impact on disease-free survival and overall survival

PURPOSE: The rationale for using adjuvant chemotherapy in colorectal cancer is to achieve better disease control and thus reduce the high rates of tumor recurrence and mortality in patients who undergo curative surgery. The current literature, including relevant abstracts, on clinical trials of fluorouracil (5-FU) in combination with high-dose leucovorin as adjuvant chemotherapy for colorectal cancer is reviewed. The intent is not to present new data, but to present the reader with a broad perspective and larger patient experience on which to base well-reasoned treatment decisions. DESIGN: Published clinical trials and abstracts presented at the 1996 American Society of Clinical Oncology (ASCO) meeting that assessed 5-FU in combination with high-dose leucovorin as adjuvant chemotherapy for colorectal cancer were surveyed. End points of interest were disease-free survival (DFS), overall survival, and toxicity. RESULTS: In randomized trials that used high-dose leucovorin at doses that ranged from daily-times-five 200 mg/m2 to weekly 500 mg/m2 in combination with 5-FU, significant improvements in both DFS and overall survival were observed over surgery alone (control). In patients treated with high-dose leucovorin/5-FU, DFS rates ranged from 71% to 77% compared with control (58% to 64%). A similar trend was seen in overall survival, with a range of 75% to 84% compared with control (63% to 77%). Toxicities observed for high-dose leucovorin administered on a weekly or daily-times-five schedule were diarrhea, stomatitis, myelosuppression, and nausea. CONCLUSION: Overall, the results of these randomized trials support the use of high-dose leucovorin/5-FU as adjuvant therapy for colorectal cancer. Longer follow-up studies are needed to compare the benefits of these different regimens in terms of survival and to characterize adverse effects, especially those that may not be immediately evident. Adjuvant therapy with high-dose leucovorin/5-FU is an effective regimen that is well tolerated by many patients with colorectal cancer.     

Multidisciplinary treatment for colorectal liver metastases

The liver is an large immunologic organ with liver-associated macrophages (Kupffer cells) and natural killer-like primitive T cells. As these effectors are activated by interleukin-2 (IL-2), we have administered IL-2-based hepatic arterial infusion therapy in the treatment of patients with liver metastases of colorectal cancer. Patients with unresectable liver metastases were administered IL-2 7 x 10(5) U and 5-fluorouracil (5-FU) 250 mg/day as a continuous infusion, with a bolus injection of mitomycin C (MMC) 4 mg once weekly. Of 25 patients treated with this regimen, 19 achieved complete or partial responses (response rate: 76%). A multi-institutional randomized trial following the pilot study showed reproducible favorable results. For patients with resectable metastases, we have administered this infusion therapy for the prevention of cancer recurrence in the liver. Patients who had undergone curative hepatectomy received IL-2 1.4 to 2.1 x 10(6) U, 5-FU 250 mg and MMC 2 to 4 mg weekly for 6 months. Of 18 patients, 12 are alive disease-free, and the 5-year overall survival rate is 75%. Recurrent cancer has developed in 6 of the 18 patients; however, no patients had recurrence in the residual liver. We believe that liver metastases of colorectal can be controlled by this multimodal treatment.     

Extracorporeal blood purification in the management of patients with hepatic failure

The current phase III studies of chemotherapy in advanced colorectal cancer include 60% to 85% of patients with the liver as a site of metastatic disease. Within the past 10 years, various modulatory combinations of 5-fluorouracil (5-FU) with agents such as leucovorin, interferon, N-(phosphonacetyl)-L-aspartate (PALA), and methotrexate have produced higher response rates than 5-FU alone. A major seven-arm study, conducted by the Southwestern Oncology Group and reported in 1995, suggested that single-agent, continuous-infusion 5-FU demonstrated the most encouraging results. Nine of 12 reported randomized studies comparing the combination of 5-FU and leucovorin with 5-FU alone report significant increases in response rates; two studies reported significant increases in survival. The meta-analysis project involving 1381 patients confirmed the increase in response rate with the combination (23%) vs. 5-FU alone (11%) but did not demonstrate any significant difference in median survival. The current issues involving 5-FU administration largely concentrate on the best approach (modulation vs. scheduling) and comprehensive evaluation of end points (quality of life, survival, and pharmacoeconomics). The current literature examining quality-of-life issues suggests that 5-FU and low-dose leucovorin produce the best overall improvement in symptoms. Others argue that continuous-infusion scheduling is also associated with a very good quality of life (although the increased cost and morbidity of continuous-infusion administration has to be factored into this consideration). An important phase III study is currently being conducted by the National Cancer Institute of Canada comparing immediate vs. delayed (until symptomatic) chemotherapy in patients with advanced colorectal cancer. Of the new approaches to therapy, perhaps the most immediately applicable are the new thymidylate synthase inhibitors (in particular, Tomudex, which produces a response rate equivalent to that of 5-FU plus leucovorin with less toxicity and a more convenient schedule).