Mutation (677 C to T) in the methylenetetrahydrofolate reductase gene aggravates hyperhomocysteinemia in hemodialysis patients

Hyperhomocysteinemia is frequent in hemodialysis patients and represents an independent risk factor for vascular disease in these patients. Elevated total homocysteine (tHcy) plasma levels can results from defective remethylation of Hcy to methionine due to decreased activity of the enzyme methylenetetrahydrofolate reductase (MTHFR). A genetic aberration in the MTHFR gene (677 C to T substitution) has been shown to result in reduced MTHFR activity. We tested the hypothesis that elevation of tHcy plasma levels in hemodialysis patients is influenced by the 677 C to T mutation of the MTHFR gene and examined the relation of the genotype with tHcy, folate and vitamin B12 plasma levels in these patients. The allelic frequency of the MTHFR mutation was evaluated in 203 patients maintained on chronic hemodialysis treatment. Total Hcy, folate, vitamin B12 levels and the MTHFR mutation were analyzed in 69 of the 203 patients and in 69 age- and sex-matched healthy control subjects. The allelic frequency of the 677 C to T transition in the MTHFR gene in hemodialysis patients was 34.7% versus 35.5% in healthy controls. Of 203 patients 26 (12.8%) were homozygous for the mutation (+/+) versus 10.2% in healthy subjects. The heterozygous (+/-) genotype was identified in 43.8% of patients versus 50.7% in controls. The mean tHcy level in hemodialysis patients was 28.7 +/- 11.0 mumol/liter versus 10.0 +/- 3.0 mumol/liter in control subjects. The mean tHcy levels were 36.4 +/- 13.4 mumol/liter in (+/+) patients and 12.2 +/- 4.5 mumol/liter in (+/+) controls, 28.7 +/- 10.8 mumol/liter in (+/-) patients and 9.9 +/- 2.7 mumol/liter in (+/-) controls and 25.4 +/- 8.5 mumol/liter in (-/-) hemodialysis patients versus 9.7 +/- 2.8 mumol/liter in (-/-) controls: There was no significant difference of folate and vitamin B12 concentrations in patients and controls with different MTHFR genotypes. Analysis of covariance including age, gender, folate concentrations, vitamin B12 levels, albumin and creatinine as covariables revealed a significant influence of the (+/+) genotype, albumin and folate status on tHcy levels in hemodialysis patients. Together, our data demonstrate that the extent of hyperhomocysteinemia in hemodialysis patients is not only the result of uremia or folate status, but is also genetically determined by the (+/+) MTHFR genotype. The presence of the 677 C to T mutation in the MTHFR gene does not appear to represent a risk factor for development of end-stage renal disease.     

A pilot study of gamma-1b-interferon in combination with fluorouracil, leucovorin, and alpha-2a-interferon

The combination of IFN-alpha-2a (IFN-alpha) and IFN-gamma-1b (IFN-gamma) has been found to produce more than additive cytotoxicity with fluorouracil (5-FU) in HT 29 colon cancer cells due to enhanced DNA-directed effects. We therefore studied the combination of IFN-gamma with IFN-alpha, 5-FU, and leucovorin (LV) in a clinical trial. Fifty-three patients received an initial cycle of 5 million units (MU)/m2 IFN-alpha s.c. on days 1-7 with 500 mg/m2 LV and 370 mg/m2 5-FU i.v. on days 2-6. IFN-gamma was then added once tolerable doses of 5-FU and IFN-alpha were established for each patient. IFN-gamma was administered at one of six dose levels between 0.3-4.8 MU/m2 s.c. on days 1-7. This design permitted comparison of the clinical toxicity and pharmacokinetics of 5-FU in two consecutive cycles in an individual treated with the same doses of 5-FU/LV/IFN-alpha in the absence and presence of IFN-gamma. In 43 matched patient cycles, the addition of IFN-gamma did not seem to worsen gastrointestinal toxicity, and skin toxicity tended to be milder. 5-FU clearance was higher in 14 cycles with IFN-gamma compared to the patient's prior cycle with the same doses of 5-FU/LV/IFN-alpha: 798 +/- 309 versus 601 +/- 250 ml/min/m2 (mean +/- SD; P = 0.04). In these 28 cycles, the median 5-FU clearance was significantly lower in 11 cycles that were complicated by more severe diarrhea: 524 versus 798 ml/min/m2 (grade 2 versus 0-1; P = 0. 0032). Overall, 38% and 26% of patients had grade 3-4 diarrhea and mucositis. Dose reductions of IFN-gamma for chronic fatigue, malaise, or anorexia were ultimately required more frequently with >/=2.4 MU/m2 (P = 0.018), and the maximum tolerated dose of IFN-gamma was considered to be 1.2 MU/m2/ day. Objective responses were seen in 41% of 29 measurable colorectal cancer patients. Compared to our previous experience with 5-FU/LV/IFN-alpha, IFN-gamma and IFN-alpha appeared to have opposite effects on 5-FU clearance. These results suggest that any potential benefit of adding IFN-alpha to 5-FU/LV on this schedule may not depend solely on alterations in 5-FU clearance.     

Folate, vitamin B12, and serum total homocysteine levels in confirmed Alzheimer disease

BACKGROUND: Recent studies suggest that vascular disease may contribute to the cause of Alzheimer disease (AD). Since elevated plasma total homocysteine (tHcy) level is a risk factor for vascular disease, it may also be relevant to AD. OBJECTIVE: To examine the association of AD with blood levels of tHcy, and its biological determinants folate and vitamin B12. DESIGN: Case-control study of 164 patients, aged 55 years or older, with a clinical diagnosis of dementia of Alzheimer type (DAT), including 76 patients with histologically confirmed AD and 108 control subjects. SETTING: Referral population to a hospital clinic between July 1988 and April 1996. MAIN OUTCOME MEASURES: Serum tHcy, folate, and vitamin B12 levels in patients and controls at entry; the odds ratio of DAT or confirmed AD with elevated tHcy or low vitamin levels; and the rate of disease progression in relation to tHcy levels at entry. RESULTS: Serum tHcy levels were significantly higher and serum folate and vitamin B12 levels were lower in patients with DAT and patients with histologically confirmed AD than in controls. The odds ratio of confirmed AD associated with a tHcy level in the top third (> or = 14 micromol/L) compared with the bottom third (< or = 11 micromol/L) of the control distribution was 4.5 (95% confidence interval, 2.2-9.2), after adjustment for age, sex, social class, cigarette smoking, and apolipoprotein E epsilon4. The corresponding odds ratio for the lower third compared with the upper third of serum folate distribution was 3.3 (95% confidence interval, 1.8-6.3) and of vitamin B12 distribution was 4.3 (95% confidence interval, 2.1-8.8). The mean tHcy levels were unaltered by duration of symptoms before enrollment and were stable for several years afterward. In a 3-year follow-up of patients with DAT, radiological evidence of disease progression was greater among those with higher tHcy levels at entry. CONCLUSIONS: Low blood levels of folate and vitamin B12, and elevated tHcy levels were associated with AD. The stability of tHcy levels over time and lack of relationship with duration of symptoms argue against these findings being a consequence of disease and warrant further studies to assess the clinical relevance of these associations for AD.     

Serum total homocysteine concentration before and after renal transplantation

BACKGROUND: Hyperhomocysteinemia is by now an established risk factor for the development of atherosclerosis. Total homocysteine concentration (tHcy) correlates inversely with glomerular filtration rate, and it is roughly three times as high in hemodialysis patients as in healthy individuals. Therefore, tHcy would be expected to fall markedly after successful renal transplantation. The aim of the present study was to assess the changes in tHcy associated with renal transplantation. METHODS: tHcy was analyzed in samples collected before renal transplantation and at six months after transplantation in 55 stable patients, all of whom were treated with cyclosporine (CS). tHcy was also analyzed in samples from 55 controls characterized by markers of renal function that matched those of the post-transplant state. RESULTS: At six months after transplantation, tHcy was significantly decreased as compared with pretransplant tHcy (27.7 +/- 14.8 vs. 36.9 +/- 21.3 micromol/liter, P < 0.001). Post-transplant tHcy was markedly higher than the tHcy of the control group (27.7 +/- 14.8 vs. 16.0 +/- 5.3 micromol/liter, P < 0.0001). The post-transplant change in tHcy ranged widely, the average change being a reduction of 14%. Sixteen patients (29%) actually manifested an increase in post-transplant tHcy. The post-transplant changes in tHcy correlated inversely with pretransplant tHcy (r = -0.66, P < 0.0001) and directly with the changes in serum albumin concentrations (r = 0.35, P < 0.05) and CS trough concentrations (r = 0.29, P < 0.05). A multivariate analysis, including the post-transplant changes in serum concentrations of folate and albumin as well as creatinine clearances explained 21% of the change in tHcy (P < 0.05). After inclusion of the CS concentration, an independent predictor, the model accounted for 28% of the post-transplant change in tHcy (P < 0.01). CONCLUSION: The post-transplant reduction in tHcy was far smaller than expected with respect to renal function, and the post-transplant changes in the major biochemical determinants of tHcy contributed relatively little to explain the change in tHcy. Thus, the results suggest the post-transplant introduction of one or more factors that induce an increase in tHcy. Treatment with CS appears to be such a factor.     

Correlation between total homocysteine and cyclosporine concentrations in cardiac transplant recipients

Increased circulating total homocysteine (tHcy) has been implicated as an independent risk factor for atherosclerotic disease. In cardiac transplant patients, accelerated coronary atherosclerosis is an important cause of late allograft failure; however, studies of tHcy in this at-risk group are limited. We sampled a cohort of 72 subjects 3.95+/-3.14 (mean +/- SD) years after transplantation and found that all had tHcy concentrations above our upper reference limit (15.0 micromol/L). The mean tHcy in the transplant group (25.4+/-7.1 micromol/L) was significantly greater than in our reference group (9.0+/-4.3 micromol/L; n = 457; P <0.001). We also examined the effect of age, gender, time since transplant, serum folate and cobalamin, total protein, urate, creatinine, albumin, and trough whole blood cyclosporine concentrations. In a multiple linear regression model, only creatinine (mean 144+/-52 micromol/L; P = 0.021) and trough cyclosporine concentrations (191+/-163 microg/L; P = 0.015) were independent positive predictors of tHcy, whereas serum folate (8.35+/-7.43 nmol/L; P = 0.018) and time since transplant (P = 0.049) were significant negative predictors. We conclude that hyperhomocysteinemia is a common characteristic of cardiac transplant recipients. Our analysis suggests that folate and renal glomerular dysfunction are important contributory factors; however, whole blood cyclosporine concentrations may also predict the degree of hyperhomocysteinemia in this population and therefore influence interpretation of any apparent response to treatment.     

Tamoxifen reduces plasma homocysteine levels in healthy women

Treatment with tamoxifen is associated with reduced incidence of myocardial infarction. As plasma homocysteine is an independent risk factor for cardiovascular disease, we studied the effects of tamoxifen on plasma homocysteine in 66 healthy women participating in the Italian prevention trial of breast cancer who were randomized in a double-blind manner to tamoxifen 20 mg day(-1) or placebo for 5 years. They were aged between 35 and 70 years, had undergone previous hysterectomy for non-malignant conditions and had no contraindications to the use of tamoxifen. Plasma levels of total homocysteine (tHcy) were measured at randomization and after 2 and 6 months. The mean +/- s.d. plasma levels of tHcy were 7.59 +/- 1.71 micromol l(-1), 7.25 +/- 1.61 and 7.09 +/- 1.33 in the tamoxifen group and 8.07 +/- 2.06, 7.93 +/- 1.77 and 8.12 +/- 2.04 in the placebo group at 0, 2 and 6 months (P = 0.008 for the between-group difference over time). The higher the baseline tHcy level, the greater was the lowering effect of tamoxifen. No statistically significant effect of age, body mass index or smoking habit on baseline tHcy levels and its variation over time was found. In conclusion, tamoxifen (20 mg day(-1) for 6 months) decreased plasma tHcy levels in healthy women. This effect may contribute to its protective effect on myocardial infarction.     

Elevated plasma osteopontin in metastatic breast cancer associated with increased tumor burden and decreased survival

Osteopontin (OPN) is a secreted, integrin-binding phosphoprotein that has been implicated in both normal and pathological processes; qualitative increases in OPN blood levels have been reported in a small number of patients with metastatic tumors of various kinds. We measured plasma OPN levels in 70 women with known metastatic breast carcinoma, 44 patient controls who were on follow-up after completion of adjuvant treatment for early breast cancer, and 35 normal volunteers. The median plasma OPN of patients with metastatic disease was 142 microgram/liter (range, 38-1312 microgram/liter) and was significantly different (P < 0.0001, Mann Whitney U test) from both control groups (medians, 60 and 47 microgram/liter; ranges, 15-117 and 22-122 microgram/liter). Furthermore, we found that increasing plasma OPN is associated with shorter survival (P < 0.001) when patients were grouped in terciles for plasma OPN. This was also demonstrated when using a Cox proportional hazards model. Median plasma OPN levels were significantly increased for three or more sites of involvement (median, 232 microgram/liter; n = 13) versus 1 or 2 metastatic sites (medians, 129 and 130 microgram/liter; n = 29 and 28, respectively). Plasma OPN levels were correlated with other biochemical markers related to the extent of disease, such as serum alkaline phosphatase, aspartate succinate aminotransaminase, and albumin (r = 0.81, 0.62, and -0.56, respectively; all P < 0.001). This study demonstrates a statistically significant elevation in plasma OPN in the majority ( approximately 70%) of a large series of patients with metastatic breast cancer when compared (95th percentile) to healthy women or patients who had completed adjuvant treatment for early-stage breast cancer. Furthermore, this is the first study to demonstrate that higher OPN levels in patients with metastatic breast cancer may be associated with an increased number of involved sites and decreased survival.     

Relationship of genital wart burden to therapeutic response to fluorouracil/epinephrine injectable gel

The efficacy of a single cycle of a new therapy for genital warts, intradermal fluorouracil/epinephrine (5-FU/epi) injectable gel, has been evaluated in 2 large pivotal trials; the objective of this study was to evaluate a second cycle of treatment. Twenty-two patients with total wart areas of 5-447 mm2 were treated with up to 2 cycles of < or =6 treatments of 5-FU/epi gel. After the first cycle of treatments, patients with warts showing a partial response or no response or new warts were continued into a second cycle. Seventy-three per cent (16/22) of patients had complete responses. Patients with total wart areas < or = 100 mm2 tended to respond completely in the first cycle of treatment (average 4.7 treatments). Patients with numerous warts or large total wart areas (>100 mm2) required an average of 7.5 treatments to achieve a complete response. Thus, a second treatment cycle may be appropriate for difficult-to-treat patients with numerous warts or large total wart areas.     

Direction of predator approach and the decision to flee to a refuge

PURPOSE: We report the local control and survival of two Phase I dose escalation trials of combined preoperative 5-fluorouracil (5-FU), low-dose leucovorin (LV), and radiation therapy followed by postoperative LV/5-FU for the treatment of patients with locally advanced and unresectable rectal cancer. METHODS AND MATERIALS: A total of 36 patients (30 primary and 6 recurrent) received two monthly cycles of LV/5-FU (bolus daily x 5). Radiation therapy (50.40 Gy) began on day 1 in the 25 patients who received concurrent treatment and on day 8 in the 11 patients who received sequential treatment. Postoperatively, patients received a median of four monthly cycles of LV/5-FU. RESULTS: The resectability rate with negative margins was 97%. The complete response rate was 11% pathologic and 14% clinical for a total of 25%. The 4-year actuarial disease-free survival was 67% and the overall survival was 76%. The crude local failure rate was 14% and the 4-year actuarial local failure rate was 30%. Crude local failure was lower in the four patients who had a pathologic complete response (0%) compared with those who either did not have a pathologic complete response (16%) or who had a clinical complete response (20%). CONCLUSION: Our preliminary data with the low-dose LV regimen reveal encouraging downstaging, local control, and survival rates. Additional follow-up is needed to determine the 5-year results. The benefit of downstaging on local control is greatest in patients who achieve a pathologic complete response.     

Characterization and cloning of a 37.6-kb plasmid carried by Legionella pneumophila recovered from patients and hospital water over a 12-year period

High-dose chemotherapy is associated with a high complete response rate and possibly some survival advantage in patients with metastatic breast cancer. We designed a clinical trial consisting of a two-step high-dose chemotherapy regimen followed by posttransplantation doxorubicin as the first chemotherapy treatment for metastatic disease. Twenty-one patients with metastatic breast cancer and no previous chemotherapy for metastatic disease were treated with high-dose cyclophosphamide (Cy; 5000 mg/m2), followed by granulocyte colony-stimulating factor. Peripheral blood stem cells were collected. Subsequently, patients received Cy (6000 mg/m2), thiotepa (500 mg/m2), and carboplatin (800 mg/m2) (CTCb) with hematopoietic rescue. Upon recovery of hematopoietic and gastrointestinal toxicity, three cycles of doxorubicin (Dox; 60 mg/m2) were delivered. After Cy, nine patients (45%) developed neutropenic fevers. There were no episodes of bacteremia. Patients received CTCb 37 days after starting Cy and had a hospital stay of 19 days. After CTCb, the median number of days to an absolute neutrophil count >5 x 10(9)/liter was 8, and the median number of days to a platelet count >20 x 10(9)/liter was 9. Neutropenic fevers occurred in 12 patients. There were no hemorrhagic complications. Fifty-five of the 63 planned courses of Dox were delivered. The median time from peripheral blood stem cell infusion to the first Dox cycle was 38 days. The median time to the second Dox cycle was 28 days, and to the last cycle was 30 days. Three episodes of neutropenic fevers were observed. Two patients developed herpes zoster. This regimen is feasible, with acceptable toxicity.     

5-fluorouracil and low-dose leucovorin as surgical adjuvant therapy from viewpoint of long-term outcome

Biochemical modulation of 5-FU by leucovorin (LV) has been demonstrated to increase the therapeutic effect compared to single agent 5-FU in the treatment of patients (pts) with advanced colorectal cancer. The purpose of this study was to determine the effectiveness of the 5-FU + LV combination as adjuvant therapy following surgery in pts with Dukes' B, C colon cancer. Pts were entered in a stratified clinical trial comparing two different combination chemotherapeutic regimens to single agent 5-FU, given orally as a control. This report summarized the result of treatment in 61 pts who were 5-FU oral alone and 32 pts who were 5-FU (375 mg/m2) and low-dose LV (20 mg/m2) intravenously for 5 days with 5-FU oral intake. 5-FU with LV regimen was associated with an improved survival compared with the single agent 5-FU oral intake (p < 0.05). 5-FU with LV regimen resulted in less recurrence in liver and lung compared with single-agent 5-FU oral intake.     

Open, randomized, multicenter trial of raltitrexed versus fluorouracil plus high-dose leucovorin in patients with advanced colorectal cancer. Tomudex Colorectal Cancer Study Group

PURPOSE: To compare raltitrexed (Tomudex; Zeneca Pharmaceuticals Ltd, Macclesfield, United Kingdom) a direct, specific thymidylate synthase (TS) inhibitor with fluorouracil (5-FU) plus high-dose leucovorin (LV) as first-line treatment for advanced colorectal cancer (ACC). PATIENTS AND METHODS: A total of 495 patients were randomized to raltitrexed (3 mg/m2) once every 3 weeks or 5-FU (400 mg/m2) plus LV (200 mg/m2) daily for 5 days every 4 weeks. RESULTS: The randomized groups were well balanced demographically. With a minimum 17-month follow-up, median survival was comparable between groups (10.9 months raltitrexed v 12.3 months 5-FU/LV; hazards ratio, 1.15; 95% confidence interval [CI], 0.93 to 1.42; P=.197), although time to progression was statistically significantly shorter in the raltitrexed group. Overall objective responses were comparable (19% raltitrexed v 18% 5-FU/LV), with more than 50% of patients in each group having stable disease. Significantly less World Health Organization (WHO) grade 3 and 4 stomatitis (2% v 16%, P < .001) and a reduced incidence of leukopenia (6% v 13%) and diarrhea (10% v 19%) occurred in the raltitrexed group (particularly at cycle 1 ). This resulted in fewer dose reductions at cycle 2 (4% raltitrexed v 28% 5-FU/LV) and early quality-of-life (QoL) benefits for raltitrexed patients. Reversible, clinically insignificant increases in transaminases were reported in 13% of raltitrexed patients. Palliative benefits of weight gain, improved performance status, and reduced disease-related symptoms were evident in both groups. CONCLUSION: Raltitrexed is confirmed as an effective option in the first-line palliative management of ACC, with comparable efficacy to and tolerability advantages (in terms of reduced incidence of stomatitis, diarrhea, and leukopenia) over 5-FU/LV. Raltitrexed has the added convenience of an every 3 weeks dosing schedule.     

Fasting and post-methionine load homocyst(e)ine values are correlated with microalbuminuria and could contribute to worsening vascular damage in non-insulin-dependent diabetes mellitus patients

The study aim was to assess the relationship between homocyst(e)inemia and microalbuminuria in non-insulin-dependent diabetes mellitus (NIDDM) patients. The study was performed on 33 NIDDM patients (16 males and 17 females), and 16 healthy control subjects (seven males and nine females). Plasma fasting and post-methionine load homocyst(e)ine (tHcy), together with other parameters that could modify tHcy levels, were assessed. There were no significant differences between NIDDM patients and controls for fasting tHcy (8.12 +/- 3.17 v 7.19 +/- 2.40 micromol/L) and post-methionine load tHcy (26.51 +/- 11.50 v 25.06 +/- 10.76 micromol/L). Moreover, there was a significant correlation between urinary albumin excretion (UAE) and fasting tHcy (r = .340, P = .05) and post-methionine load tHcy (r = .502, P = .004) in NIDDM patients. Fasting tHcy was correlated both with post-methionine load tHcy (r = .429, P = .01) and with vitamin B12 (r = -.349, P = .04) in NIDDM patients. Microalbuminuric NIDDM patients had higher fasting tHcy (9.05 +/- 3.83 micromol/L) than normoalbuminurics (7.12 +/- 1.95 micromol/L). In addition, NIDDM patients with complications presented higher fasting tHcy values than the group without complications (9.61 +/- 3.34 v 6.53 +/- 2.09 micromol/L, Kolmogorov-Smirnov two-sample test for nonparametric data [KS] = 1.794, P = .003), without any other significant differences in the parameters considered. tHcy could be an important risk factor worsening the prognosis in NIDDM patients, especially microalbuminuric patients. Microalbuminuric NIDDM patients could be particularly prone to hyperhomocyst(e)inemia, probably due to endothelial or renal dysfunction with a reduction in the scavenging of tHcy.     

Long-term complete response in two cases of liver metastases from rectal and gastric cancer treated with intra-arterial infusion chemotherapy of leucovorin and 5-fluorouracil

Intra-arterial infusion chemotherapy combined with leucovorin (LV) and 5-fluorouracil (5-FU) was performed in two patients with multiple metastases from rectal and gastric cancer. In each patient LV 45 mg was infused as a bolus just before and after 5-FU 1,000 mg/4 hrs administration. Thereafter 5-FU dose was decreased gradually. This regimen was principally repeated weekly on an outpatient basis. In both patients PR was detectable 3 and 4 months after the beginning of chemotherapy, and CR was obtained in 21 and 6 months, respectively. Neither patient showed any signs of recurrence and are in good health 35 and 30 months after initiation of chemotherapy. These findings suggest that our protocol has an excellent anti-tumor effect and improves the QOL in some patients for a long time.     

A phase II study of irinotecan alternated with five days bolus of 5-fluorouracil and leucovorin in first-line chemotherapy of metastatic colorectal cancer

PURPOSE: This multicenter phase II study was designed to assess the efficacy of the alternating schedule of irinotecan (CPT-11) with bolus 5-fluorouracil (5-FU) and leucovorin (LV) in first-line chemotherapy for metastatic colorectal cancer (CRC). PATIENTS AND METHODS: Patients with histologically proven metastatic colorectal cancer, and at least one bidimensionally measurable lesion, aged 18-70, with performance status < or = 2, normal baseline biological values and no prior chemotherapy (or only adjuvant chemotherapy completed > or = 6 months before study entry) were selected. Treatment was irinotecan 350 mg/m2, i.v., day 1, alternating with leucovorin 20 mg/m2 i.v. and 5-FU 425 mg/m2, i.v. daily for five consecutive days, day 22-26 (Mayo Clinic regimen). One alternating cycle was to be performed every six weeks. Patients were evaluated for efficacy every alternating cycle. Treatment was administered until five alternating cycles, disease progression, unacceptable toxicity or patient refusal. RESULTS: Thirty-three patients (28 chemotherapy-na?ve and five with prior adjuvant treatment completed > 1 year prior to accrual) were enrolled. The objective response rate (RR) was 30% (95% CI: 16-49; 10 patients/33; nine partial response and one complete response). All responses were reviewed by an independent external review committee. An additional 49% of patients had stable disease. The median survival was 16 months, the one year survival amounted to 58% and the median progression free survival was 7.2 months. Relative dose intensity was nearly 90% for both drugs. Grade 3-4 diarrhea and neutropenia were the most frequent severe toxic events, seen in 24% and 64% of patients, respectively. CONCLUSIONS: The alternating schedule of CPT-11 350 mg/m2 with five days bolus of 5-FU and low dose LV is an active and feasible regimen as front-line therapy for metastatic CRC. It is well tolerated, without evidence of overlapping toxicity. The response rate appears promising with regard to that expected with either single agent. This regimen warrants further assessment in randomized trials.     

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.     

Plasma homocysteine concentrations in patients with type 1 diabetes

OBJECTIVE: To determine the plasma concentration of total homocysteine (tHcy), a recognized risk factor for vascular disease, in patients with type 1 diabetes and to examine the relationships with age, sex, duration of diabetes, microvascular complications and neuropathy, and folic acid concentration. RESEARCH DESIGN AND METHODS: Plasma tHcy and folic acid concentrations were measured in a randomly selected cohort of type 1 diabetic patients (n = 119), well characterized as regards microvascular complications, and in a matched control group (n = 51). RESULTS: Plasma tHcy was higher in male than in female control subjects (geometric mean [95% CI]: 9.3 [8.0-10.9] vs. 6.1 [5.2-7.2] micromol/l, P < 0.001), as previously described, but there was no sex difference in diabetic patients. Plasma tHcy significantly correlated with age in patients (r = 0.348, P < 0.01) but not in control subjects (r = 0.007, P = 0.96). Male patients without microvascular complications had lower plasma tHcy concentrations than did male control subjects (6.2 [5.1-7.5] vs. 9.3 [8.0-10.9] micromol/l, P < 0.001), but values in female patients without complications were similar to those of female control subjects. Plasma folic acid concentration was higher in diabetic patients than in control subjects. The expected negative association between plasma tHcy and folic acid was stronger in control subjects than in patients. CONCLUSIONS: Subnormal tHcy concentrations in male patients, the absence of a sex difference, and the positive association with age indicate that homocysteine metabolism differs between type 1 diabetic patients and control subjects. Homocysteine is unlikely to be of pathogenic significance in patients, particularly male subjects, with early microvascular disease and/or neuropathy.     

A phase II study of 5-fluorouracil, leucovorin and cisplatin (FLP) for metastatic gastric cancer

The modulation of 5-fluorouracil (5-FU) with folinic acid (leucovorin, LV) is more efficacious than 5-FU alone in the treatment of metastatic colorectal cancer, and the combination of 5-FU with cisplatin is currently one of the most active regimens in advanced gastric cancer. A phase II study was therefore conducted to test the efficacy and toxicity of the combination of 5-FU, LV and cisplatin (FLP) in metastatic gastric cancer. 28 patients entered the study. Metastatic sites were observed in the liver (in 21 patients), the peritoneum (in 8), the lymph nodes (in 7) or the bones (in 1) and a local recurrence was noted in 4 cases. The performance status (using World Health Organisation criteria) was 0 for 13 patients and 1 or 2 for the others. Cycles of treatment were administered every 28 days and consisted of LV 200 mg/m2/day for 5 days followed by 5-FU 400 mg/m2/day for 5 days with cisplatin 100 mg/m2 on day 2. The response rate for the 27 evaluable patients was 51.8% (95% confidence interval (CI), 33-70.6%). There were four complete responses (14.8%) and 10 partial responses (37%). Median survival was 11 months and 4 patients were alive at 2 years. Both response rate and survival were better for patients with a good performance status. The overall toxicity was very low, except for 1 patient who died of dehydration and cardiac failure. In conclusion, the FLP protocol was effective and well tolerated in patients with metastatic gastric cancer.     

Adjuvant treatment of high-risk breast cancer using multicycle high-dose chemotherapy and filgrastim-mobilized peripheral blood progenitor cells

Women with primary breast cancer associated with extensive axillary node involvement or large primary tumors have a very poor prognosis despite treatment with standard-dose adjuvant chemotherapy. In an attempt to improve the outlook of these patients, we investigated the safety and feasibility of delivering three cycles of high-dose epirubicin and cyclophosphamide supported with filgrastim-mobilized peripheral blood progenitor cells (PBPC). Fifteen previously untreated women, median age 50 (range, 30-58) years, with poor prognosis early stage breast cancer received filgrastim (12 microgram/kg daily for 6 days) prior to chemotherapy to mobilize progenitor cells. Patients were then given three cycles of epirubicin (200 mg/m2) and cyclophosphamide (4 g/m2) at planned 28-day intervals, each followed by infusion of one third of the PBPC collected and daily administration of filgrastim (5 microgram/kg s.c.). Three leukaphereses collected a median of 114.9 (range, 22.7-273.5) x 10(4) granulocyte-macrophage-colony-forming cells/kg body weight. Hemopoietic recovery was rapid after each cycle, and there was no correlation between the rate of recovery and the number of granulocyte-macrophage-colony-forming cells infused. There was a small but significant progressive delay in recovery from hematological and nonhematological toxicities across the three cycles. Left ventricular ejection fraction fell to below 50% in eight (53%) patients, but none developed congestive cardiac failure. Two patients did not complete three cycles because of insufficient PBPC for a third cycle (n = 1) and 2-mercaptoethane sodium sulfonate- related drug reaction during the second cycle (n = 1). There were no deaths during the study or during the follow-up period (median, 70 weeks; range, 50-85 weeks), and no late toxicities occurred. Therefore, we concluded that the delivery of multiple cycles of nonmyeloablative, dose-intensive chemotherapy supported by PBPC and filgrastim is safe, and may be widely applicable to a variety of common chemosensitive cancers with a poor prognosis. The efficacy of three cycles of high-dose epirubicin and cyclophosphamide is to be compared with standard-dose chemotherapy in a randomized trial in patients with high-risk, operable stage II and III breast cancer.     

Excess prevalence of fasting and postmethionine-loading hyperhomocysteinemia in stable renal transplant recipients

Hyperhomocysteinemia, either fasting or after methionine loading, may contribute to the increased incidence of cardiovascular disease events experienced by renal transplant recipients. Limited data are available on fasting homocysteine (Hcy) levels, and none on postmethionine-loading Hcy levels, in these patients. We assessed the prevalence and potential determinants of fasting and postmethionine-loading hyperhomocysteinemia in 29 stable renal transplant recipients and 58 age- and sex-matched, population-based controls free of renal disease with serum creatinine levels of 1.5 mg/dL or less. Total (t) plasma Hcy was determined fasting and 2 hours after methionine loading, along with fasting determinations of the B-vitamin cofactors/substrates for Hcy metabolism, ie, pyridoxal 5'-phosphate, B-12, and folate and serum creatinine. Geometric mean fasting (18.1 versus 9.8 microM, P < .001) and postmethionine-loading increase (22.0 versus 15.2, P = .001) in tHcy levels were significantly greater in the renal transplant recipients, as were the prevalence odds (with 95% confidence intervals) for fasting [14.8 (3.4-64.7)], postmethionine loading [6.9 (1.5-32.8)], combined fasting and postmethionine-loading [18.0 (2.3-142.1)] hyperhomocysteinemia, and inadequate circulating folate [4.2 (1.1-16.5)] or pyridoxal 5'-phosphate [3.2 (0.9-11.0) status. Correlation analyses suggested important potential relationships between creatinine and both fasting (+0.64, P < .001) and postmethionine-load increase (+0.38, P = .045) in tHcy, folate and fasting (-0.41, P = .025) tHcy, and pyridoxal 5'-phosphate and postmethionine-loading increase (-0.33, P = .091) in tHcy. We conclude that there is an excess prevalence of fasting and postmethionine-loading hyperhomocysteinemia in stable renal transplant recipients. Renal function is related to both fasting and postmethionine loading-hyperhomocysteinemia, inadequate folate status is associated with fasting hyperhomocysteinemia, and inadequate vitamin B-6 status may be related to postmethionine-loading hyperhomocysteinemia in this patient population.